Aims. The best surgical strategy for the management of displaced bucket-handle (BH) meniscal tears in an anterior cruciate ligament (ACL)-deficient knee is unclear. Combining meniscal repair with ACL reconstruction (ACLR) is thought to improve meniscal healing rates; however, patients with displaced BH meniscal tears may lack extension. This leads some to advocate staged surgery to avoid postoperative stiffness and loss of range of motion (ROM) following ACLR. Methods. We reviewed the data for a consecutive series of 88 patients (mean age 27.1 years (15 to 49); 65 male (74%) and 23 female (26%)) who underwent single-stage repair of a displaced BH meniscal tear (67 medial (76%) and 21 lateral (24%)) with concomitant hamstring autograft ACLR. The patient-reported outcome measures (PROMs) EuroQol visual analogue scale (EQ-VAS), EuroQol five-dimension health questionnaire (EQ-5D), Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee score (IKDC), and Tegner score were recorded at final follow-up. A Kaplan-Meier survival analysis was performed to estimate meniscal repair survivorship. Analyses were performed with different cut-offs for meniscal and ACL injury-to-surgery time (within three weeks, three to ten weeks, and more than ten weeks). Results. Meniscal repair survivorship at a median final follow-up of 55 months (interquartile range (IQR) 24 to 91) was 82% (95% confidence interval 70 to 89). A total of 13 meniscus repairs failed (12 requiring meniscectomy and one requiring a further meniscal repair). At final follow-up, median PROMs were: EQ-VAS 85 (IQR 75 to 90), EQ-5D Index 0.84 (IQR 0.74 to 1.00), KOOS Pain 89 (IQR 80 to 94), KOOS Symptoms 82 (IQR 71 to 93), KOOS Activities of Daily Living 97 (IQR 91 to 100), KOOS Sport and Recreation 80 (IQR 65 to 90), KOOS Quality of Life 69 (IQR 53 to 86), IKDC 82.8 (IQR 67.8 to 90.8), and Tegner 6 (IQR 4 to 7). Two patients underwent revision ACLR following further injuries. One patient had an arthroscopic washout for infection at 11 days post-BH meniscal repair/ACLR. Four patients (4.5%) required a further procedure for stiffness, reduced ROM, and pain, and all were operated on within three weeks of meniscal injury. There was no difference in the interval between meniscal injury and surgery between repairs that failed and those that survived. Conclusion. These data suggest that concomitant ACLR with repair of displaced BH meniscal tears, even if they have been displaced for some time, appears to afford satisfactory PROMs and good survivorship. Repairs within three weeks of meniscal injury may be associated with higher rates of postoperative reintervention for stiffness. Cite this article: Bone Joint J 2022;104-B(6):680–686

Aims. Our purpose was to describe an unusual series of 21 patients with fungal osteomyelitis after an anterior cruciate ligament reconstruction (ACL-R). Methods. We present a case-series of consecutive patients treated at our institution due to a severe fungal osteomyelitis after an arthroscopic ACL-R from November 2005 to March 2015. Patients were referred to our institution from different areas of our country. We evaluated the amount of bone resection required, type of final reconstructive procedure performed, and Musculoskeletal Tumor Society (MSTS) functional score. Results. A total of 21 consecutive patients were included in the study; 19 were male with median age of 28 years (IQR 25 to 32). All ACL-R were performed with hamstrings autografts with different fixation techniques. An oncological-type debridement was needed to control persistent infection symptoms. There were no recurrences of fungal infection after median of four surgical debridements (IQR 3 to 6). Five patients underwent an extensive curettage due to the presence of large cavitary lesions and were reconstructed with hemicylindrical intercalary allografts (HIAs), preserving the epiphysis. An open surgical debridement was performed resecting the affected epiphysis in 15 patients, with a median bone loss of 11 cm (IQR 11.5 to 15.6). From these 15 cases, eight patients were reconstructed with allograft prosthesis composites (APC); six with tumour-type prosthesis (TTP) and one required a femoral TTP in combination with a tibial APC. One underwent an above-the-knee amputation. The median MSTS functional score was 20 points at a median of seven years (IQR 5 to 9) of follow-up. Conclusion. This study suggests that mucormycosis infection after an ACL-R is a serious complication. Diagnosis is usually delayed until major bone destructive lesions are present. This may originate additional massive reconstructive surgeries with severe functional limitations for the patients. Level of evidence: IV. Cite this article: Bone Joint Open 2020;2(1):3–8

The Oxford unicompartmental knee replacement (UKR) is an established treatment option in the management of symptomatic end-stage medial compartmental osteoarthritis (MCOA), which works well in the young and active patient. However, previous studies have shown that it is reliable only in the presence of a functionally intact anterior cruciate ligament (ACL). This review reports the outcomes, at a mean of five years and a maximum of ten years, of 52 consecutive patients with a mean age of 51 years (36 to 57) who underwent staged or simultaneous ACL reconstruction and Oxford UKR. At the last follow-up (with one patient lost to follow-up), the mean Oxford knee score was 41 (. sd. 6.3; 17 to 48). Two patients required conversion to TKR: one for progression of lateral compartment osteoarthritis and one for infection. Implant survival at five years was 93% (95% CI 83 to 100). All but one patient reported being satisfied with the procedure. The outcome was not significantly influenced by age, gender, femoral or tibial tunnel placement, or whether the procedure was undertaken at one- or two-stages. In summary, ACL reconstruction and Oxford UKR gives good results in patients with end-stage MCOA secondary to ACL deficiency

Aims. The success of anterior cruciate ligament reconstruction (ACLR) depends on osseointegration at the graft-tunnel interface and intra-articular ligamentization. Our aim was to conduct a systematic review of clinical and preclinical studies that evaluated biological augmentation of graft healing in ACLR. . Materials and Methods. In all, 1879 studies were identified across three databases. Following assessment against strict criteria, 112 studies were included (20 clinical studies; 92 animal studies). . Results. Seven categories of biological interventions were identified: growth factors, biomaterials, stem cells, gene therapy, autologous tissue, biophysical/environmental, and pharmaceuticals. The methodological quality of animal studies was moderate in 97%, but only 10% used clinically relevant outcome measures. The most interventions in clinical trials target the graft-tunnel interface and are applied intraoperatively. Platelet-rich plasma is the most studied intervention, but the clinical outcomes are mixed, and the methodological quality of studies was suboptimal. Other biological therapies investigated in clinical trials include: remnant-augmented ACLR; bone substitutes; calcium phosphate-hybridized grafts; extracorporeal shockwave therapy; and adult autologus non-cultivated stem cells. Conclusion. There is extensive preclinical research supporting the use of biological therapies to augment ACLR. Further clinical studies that meet the minimum standards of reporting are required to determine whether emerging biological strategies will provide tangible benefits in patients undergoing ACLR. Cite this article: Bone Joint J 2018;100-B:271–84

Aims

The aim of this study was to evaluate the association between chondral injury and interval from anterior cruciate ligament (ACL) tear to surgical reconstruction (ACLr).

Background. Surgical reconstruction of the anterior cruciate ligament is a common practice to treat the disability or chronic instability of the knee. Several factors associated with success or failure of the ACL reconstruction, including surgical technique and graft material and graft tension. We aimed to show how we can optimize the graft properties and achieve better post surgical outcomes during ACL reconstruction using 3-dimensional computational finite element simulation. Methods. In this paper, 3-dimensional model of the knee was constructed to investigate the effect of graft tensioning on the knee joint biomechanics. Four different grafts were compared: 1) bone-patellar tendon-bone graft (BPTB) 2) Hamstring tendon 3) BPTB and a band of gracilis 4) Hamstring and a band of gracilis. The initial graft tension was set as “0, 20, 40, or 60N”. The anterior loading was set to 134 N. Findings. Our study shows that the use of the discarded gracilis tendon, which usually excised after graft fixation, could be associated with a host of merits. Our results show that preserving this excess part of gracilis would decrease the required pretention load and, subsequently, could optimize biomechanical properties of the knee. Conclusion. Required pretension during surgery will have decreased significantly by adding a band of gracilis to the proper graft. Therefore, in addition to achieving normal stability of the knee, we can have lower risk of degradation

Cite this article: Bone Joint Open 2020;1-11:706–708.

Objectives

Our aim was to assess the use of intra-operative fluoroscopy in the assessment of the position of the tibial tunnel during reconstruction of the anterior cruciate ligament (ACL).

Aims. Anterior cruciate ligament (ACL) surgery in children and the adolescent population has increased steadily over recent years. We used a national database to look at trends in ACL reconstruction and rates of serious complications, growth disturbance, and revision surgery, over 20 years. Methods. All hospital episodes for patients undergoing ACL reconstruction, under the age of 20 years, between 1 April 1997 and 31 March 2017, were extracted by procedure code from the national Hospital Episode Statistics (HES). Population standardized rates of intervention were determined by age group and year of treatment. Subsequent rates of serious complications including reoperation for infection, growth disturbance (osteotomy, epiphysiodesis), revision reconstruction, and/or contralateral ACL reconstruction rates were determined. Results. Over the 20 year period, 16,125 ACL reconstructions were included. The mean age of patients was 16.9 years (SD 2.0; 27.1% female, n = 4,374/16,125). The majority of procedures were observed in the 15 to 19 years age group. The rate of ACL reconstruction increased 29-fold from 1997 to 1998, to 2016 to 2017. Within 90 days of ACL reconstruction, the rate of reoperation for infection was 0.31% (95% confidence interval (CI) 0.23 to 0.41, n = 50/16,125) and the rate of pulmonary embolism was 0.037% (95%.CI 0.014 to 0.081, n = 6/16,125). Of those with minimum five-year follow-up following ACL reconstruction (n = 7,585), 1.00% of patients subsequently underwent an osteotomy (95% CI 0.79 to 1.25, n = 76/7,585), 0.09% an epiphysiodesis (95% CI 0.04 to 0.19, n = 7/7,585), 7.46% revision ACL reconstruction (95% CI 6.88 to 8.08, n = 566/7,585), and 6.37% contralateral ACL reconstruction (95% CI 5.83 to 6.94, n = 483/7,585). Conclusion. Rates of paediatric and adolescent ACL reconstruction have increased 29-fold over the last 20 years. Despite the increasing rate in the younger population, the risk of serious complications, including further surgery for growth disturbance is very low. The results of our study provide a point of reference for shared decision making in the management of ACL injury in the paediatric and adolescent population. Cite this article: Bone Joint J 2020;102-B(2):239–245

To address the current challenge of anterior cruciate ligament (ACL) reconstruction, this study is the first to fabricate a braided collagen rope (BCR) which mimics native hamstring for ACL reconstruction. The study aims to evaluate the biological and biomechanical properties of BCR both in vivo and vitro. Rabbit ACL reconstruction model using collagen rope and autograft (hamstring tendon) was conducted. The histological and biomechanical evaluations were conducted at 6-, 12-, 18, 26-week post-operation. In vitro study included cell morphology analysis, cell function evaluation and RNA sequencing of the tenocytes cultured on BCR. A cadaver study was also conducted to verify the feasibility of BCR for ACL reconstruction. BCR displays satisfactory mechanical strength similar to hamstring graft for ACL reconstruction in rabbit. Histological assessment showed BCR restore ACL morphology at 26 weeks similar to native ACL. The superior dynamic ligamentization in BCR over autograft group was evidenced by assessment of cell and collagen morphology and orientation. The in vitro study showed that the natural collagen fibres within BCR enables to signal the morphology adaptation and orientation of human tenocytes in bioreactor. BCR enables to enhance cell proliferation and tenogenic expression of tenocytes as compared to hydrolysed collagen. We performed an RNA-Sequencing (RNA-seq) experiment where RNA was extracted from tenocyte seeded with BCR. Analysis of enriched pathways of the up-regulated genes revealed that the most enriched pathways were the Hypoxia-inducible factor 1-alpha (HIF1A) regulated networks, implicating the possible mechanism BCR induced ACL regeneration. The subsequent cadaver study was conducted to proof the feasibility of BCR for ACL reconstruction. This study demonstrated the proof-of-concept of bio-textile braided collagen rope for ACL reconstruction, and the mechanism by which BCR induces natural collagen fibres that positively regulate morphology and function of tenocytes

The purpose of this study is to assess the long term results of combined ACL reconstruction and unicompartmental knee replacements (UKR). These patients have been selected for this combined operation due to their combination of instability symptoms from an absent ACL and unicompartmental arthritis. Retrospective review of 44 combined UKR and ACL reconstruction by a single surgeon. Surgeries included both medial and lateral UKR combined with either revision ACL reconstruction or primary ACL reconstruction. Patient reported outcomes were obtained preoperatively, at one year, 5 years and 10 years. Revision rate was followed up over 13 years for a mean of 7.4 years post-surgery. The average Oxford score at one year was 43 with an average increase from pre-operation to 1 year post operation of 15. For the 7 patients with 10 year follow up average oxford score was 42 at 1 year, 43 at 5 years and 45 at 10 years. There were 5 reoperations. 2 for revision to total knee arthroplasty and 1 for an exchange of bearing due to wear. The other 2 were the addition of another UKR. For those requiring reoperation the average time was 8 years. Younger more active patients presenting with ACL deficiency causing instability and unicompartmental arthritis are a difficult group to manage. Combining UKR and ACL reconstruction has scant evidence in regard to long term follow up but is a viable option for this select group. This paper has one of the largest cohorts with a reasonable follow up averaging 7.4 years and a revision rate of 11 percent. Combined unilateral knee replacements and ACL reconstruction can be a successful operation for patients with ACL rupture causing instability and unicompartmental arthritis

Arthrofibrosis is a less common complication following anterior cruciate ligament (ACL) reconstruction and there are concerns that undergoing early surgery may be associated with arthrofibrosis. The aim of this study was to identify the patient and surgical risk factors for arthrofibrosis following primary ACL reconstruction. Primary ACL reconstructions prospectively recorded in the New Zealand ACL Registry between April 2014 and December 2019 were analyzed. The Accident Compensation Corporation (ACC) database was used to identify patients who underwent a subsequent reoperation with review of operation notes to identify those who had a reoperation for “arthrofibrosis” or “stiffness”. Univariate Chi-Square test and multivariate Cox regression analysis was performed. Hazard ratios (HR) with 95% confidence intervals (CI) were computed to identify the risk factors for arthrofibrosis. 9617 primary ACL reconstructions were analyzed, of which 215 patients underwent a subsequent reoperation for arthrofibrosis (2.2%). A higher risk of arthrofibrosis was observed in female patients (adjusted HR = 1.67, 95% CI 1.22 – 2.27, p = 0.001), patients with a history of previous knee surgery (adjusted HR = 1.97, 95% CI 1.11 – 3.50, p = 0.021) and when a transtibial femoral tunnel drilling technique was used (adjusted HR = 1.55, 95% CI 1.06 – 2.28, p = 0.024). Patients who underwent early ACL reconstruction within 6 weeks of their injury did not have a higher risk of arthrofibrosis when compared to patients who underwent surgery more than 6 weeks after their injury (3.5% versus 2.1%, adjusted HR = 1.56, 95% CI 0.97 – 2.50, p = 0.07). Age, graft type and concomitant meniscal injury did not influence the rate of arthrofibrosis. Female sex, a history of previous knee surgery and a transtibial femoral tunnel drilling technique are risk factors for arthrofibrosis following primary ACL reconstruction

Abstract. Aims. Growth disturbances after transphyseal paediatric ACL reconstruction have led to the development of physeal-sparing techniques. However, evidence in their favour remains weak. This study reviews the literature to identify factors associated with growth disturbances in paediatric ACL reconstructions. Materials and Methods. Web of Science, Scopus and Pubmed were searched for case series studying paediatric ACL reconstructions. Titles, abstracts, text, results and references were examined for documentation of growth disturbances. Incidences of graft failures were also studied in these selected studies. Results. 78 studies with 2693 paediatric ACL reconstructions had 70 growth disturbances (2.6%). Of these 17 were varus, 26 valgus, 13 shortening, 14 lengthening and 5 patients had reduced tibial slope. Coronal plane deformities were seen more frequently with eccentric physeal arrest and lengthening with intraepiphyseal tunnelling. Shortening and reduced tibial slope were related to large central physeal arrest and anterior tibial physeal arrest respectively. Extraphyseal technique were least likely to have growth disturbances. 62 studies documented 166 graft failures in 2120 patients (7.83%). Conclusion. Growth disturbances resulting from transphyseal ACL reconstruction can be minimised by keeping drill size small, drilling steep and away from the physeal periphery. Insertion of bone plug, hardware or synthetic material through the drilled physis should be avoided. The evidence to accurately quantify such growth disturbances till skeletal maturity remains weak. Robust long term studies such as national ligament registries may standardise preoperative and postoperative outcome assessment to further characterise the risk of growth disturbance and re-ruptures

The anterior cruciate ligament (ACL) is frequently injured in elite athletes, with females up to eight times more likely to suffer an ACL tear than males. Biomechanical and hormonal factors have been thoroughly investigated; however, there remain unknown factors that need investigation. The mechanism of injury differs between males and females, and anatomical differences contribute significantly to the increased risk in females. Hormonal factors, both endogenous and exogenous, play a role in ACL laxity and may modify the risk of injury. However, data are still limited, and research involving oral contraceptives is potentially associated with methodological and ethical problems. Such characteristics can also influence the outcome after ACL reconstruction, with higher failure rates in females linked to a smaller diameter of the graft, especially in athletes aged < 21 years. The addition of a lateral extra-articular tenodesis can improve the outcomes after ACL reconstruction and reduce the risk of failure, and it should be routinely considered in young elite athletes. Sex-specific environmental differences can also contribute to the increased risk of injury, with more limited access to and availablility of advanced training facilities for female athletes. In addition, football kits are designed for male players, and increased attention should be focused on improving the quality of pitches, as female leagues usually play the day after male leagues. The kit, including boots, the length of studs, and the footballs themselves, should be tailored to the needs and body shapes of female athletes. Specific physiotherapy programmes and training protocols have yielded remarkable results in reducing the risk of injury, and these should be extended to school-age athletes. Finally, psychological factors should not be overlooked, with females’ greater fear of re-injury and lack of confidence in their knee compromising their return to sport after ACL injury. Both intrinsic and extrinsic factors should be recognized and addressed to optimize the training programmes which are designed to prevent injury, and improve our understanding of these injuries. Cite this article: Bone Joint J 2023;105-B(10):1033–1037

The principal of “function priority, early rehabilitation, and return to sports” is now the goal for sports injury rehabilitation. Neuromuscular electrical stimulation for anterior cruciate ligament (ACL) reconstruction is a rising procedure for early rehabilitation. This paper systematically assessed the effects of neuromuscular electrical stimulation on postoperative ACL reconstruction to provide guidance for physiotherapist and patient when designing a suitable rehabilitation protocol. To evaluate the interventional outcomes of neuromuscular electrical stimulation following ACL reconstruction, we searched PubMed, EMbase, the Cochrane Library, Web of Science and CNKI to collect all randomized controlled trials (RCTs) comparing the effects with neuromuscular electrical stimulation and without intervention on rehabilitation after ACL reconstruction up to January 30, 2022. Two investigators independently performed literature screening, data extraction, bias assessment of risk, and used RevMan 5.3 software to conduct a meta-analysis. A total of six RCTs were included, and the results showed that the use of neuromuscular electrical stimulation after anterior cruciate ligament reconstruction significantly improved the International Knee Documentation Committee (IKDC) scores (MD 6.33, 95% CI [-0.43, 12.22]; I2 = 66%; p = 0.040), the Lysholm score (MD 7.94, 95% CI [6.49, 9.39]; I2 = 89%; p < 0.001), and the range of motion (ROM) (MD 9.99, 95% CI [7.97, 12.02]; I2 = 81%; p < 0.001) in the knees when compared to the control group without using neuromuscular electrical stimulation. Existing evidence show that neuromuscular electrical stimulation is beneficial for early rehabilitation after ACL reconstruction. The use of neuromuscular electrical stimulation is encouraged in the design of rehabilitation protocol. However, due to the limited number of RCT studies and the small sample size, further multi-center RCTs with more participants are needed for a higher-level evidence

Aims. To verify whether secretory leucocyte protease inhibitor (SLPI) can promote early tendon-to-bone healing after anterior cruciate ligament (ACL) reconstruction. Methods. In vitro: the mobility of the rat bone mesenchymal stem cells (BMSCs) treated with SLPI was evaluated by scratch assay. Then the expression levels of osteogenic differentiation-related genes were analyzed by real-time quantitative PCR (qPCR) to determine the osteogenic effect of SLPI on BMSCs. In vivo: a rat model of ACL reconstruction was used to verify the effect of SLPI on tendon-to-bone healing. All the animals of the SLPI group and the negative control (NC) group were euthanized for histological evaluation, micro-CT scanning, and biomechanical testing. Results. SLPI improved the migration ability of BMSCs and upregulated the expression of genes related to osteogenic differentiation of BMSCs in vitro. In vivo, the SLPI group had higher histological scores at the tendon-bone interface by histological evaluation. Micro-CT showed more new bone formation and bone ingrowth around the grafted tendon in the SLPI group. Evaluation of the healing strength of the tendon-bone connection showed that the SLPI group had a higher maximum failure force and stiffness. Conclusion. SLPI can effectively promote early tendon-to-bone healing after ACL reconstruction via enhancing the migration and osteogenic differentiation of BMSCs. Cite this article: Bone Joint Res 2022;11(7):503–512

The bone-patellar tendon-bone (BTB) autograft has a lower rate of graft failure but a higher rate of contralateral anterior cruciate ligament (ACL) injury after primary ACL reconstruction. Subsequent contralateral injury may be a marker of success of the BTB graft, but it is unclear whether the type of graft influences the rate of return to sport. This study aimed to compare the rates of return to weekly sport and return to preinjury activity levels between the BTB and hamstring tendon autografts following primary ACL reconstruction. Prospective data on primary ACL reconstructions recorded in the New Zealand ACL Registry between April 2014-November 2019 were analyzed. The primary outcome was return to weekly sport, defined as a Marx activity score of 8, at 2-year follow-up. The secondary outcome was return to preinjury activity level, defined as a post-operative Marx activity score that was equal or greater to the patient's preinjury Marx score. Return to sport was compared between the BTB and hamstring tendon autografts via multivariate binary logistic regression with adjustment for patient demographics. 4259 patients were analyzed, of which 50.3% were playing weekly sport (n = 2144) and 28.4% had returned to their preinjury activity level (n = 1211) at 2-year follow-up. A higher rate of return to weekly sport was observed with the BTB autograft compared to the hamstring tendon autograft (58.7% versus 47.9%, adjusted odds ratio = 1.23, p = 0.009). Furthermore, the BTB autograft had a higher rate of return to preinjury activity levels (31.5% versus 27.5%, adjusted odds ratio = 1.21, p = 0.025). The BTB autograft is associated with a higher return to sport and may explain the higher rate of contralateral ACL injury following primary ACL reconstruction

Aims. The aim of this prospective study was to assess the long-term clinical, radiological, functional, and quality of life (QoL)-related outcome of patients treated with the synthetic Ligament Advanced Reinforcement System (LARS) device for anterior cruciate ligament (ACL) rupture. Methods. A total of 41 patients who underwent ACL reconstruction with the LARS device (mean age 39.8 years (SD 12.1 ); 32% females (n = 13)) were prospectively included between August 2001 and March 2005. MRI scans and radiographs were performed at a median follow-up of 2.0 years (interquartile range (IQR) 1.3 to 3.0; n = 40) and 12.8 years (IQR 12.1 to 13.8; n = 22). Functional and QoL-related outcome was assessed in 29 patients at a median follow-up of 12.8 years (IQR 12.0 to 14.0) and clinically reconfirmed at latest median follow-up of 16.5 years (IQR 15.5 to 17.9). International Knee Documentation Committee (IKDC) and Tegner scores were obtained pre- and postoperatively, and Lysholm score postoperatively only. At latest follow-up, range of motion, knee stability tests, 36-Item Short Form Health Survey (SF-36), and IKDC scores were ascertained. Complications and reoperations during follow-up were documented. Results. Cumulative complication rate was 66% (n = 27), with 11 developing within one year from surgery and 16 after one year (including five patients with both early and late complications). Ten graft failures (24%) and eight cases of reactive synovitis were observed (20%). All 11 patients with early complications and ten with late complications underwent reoperation (including five with another surgical procedure for early complications), amounting to a cumulative reoperation rate of 51% (n = 21). Revision ACL reconstruction was performed in one patient (2.4%). Median IKDC at latest follow-up was 89.7 (IQR 78.2 to 93.1), being significantly worse in the event of previous complications. Lachman test was positive in 56% (n = 15) of reconstructed knees. All norm-based SF-36 items were at or above median at latest follow-up, and did not differ depending on development of complications. Conclusion. Despite good functional and QoL-related results in the long term, the cumulative complication rate of 66%, including graft failures and reactive synovitis, has to be viewed with great concern. Cite this article: Bone Joint J 2022;104-B(2):242–248

Meniscal repairs are commonly performed during anterior cruciate ligament (ACL) reconstruction. This study aimed to identify the risk factors for meniscal repair failure following concurrent primary ACL reconstruction. Primary ACL reconstructions with a concurrent repair of a meniscal tear recorded in the New Zealand ACL Registry between April 2014 and December 2018 were analyzed. Meniscal repair failure was defined as a patient who underwent subsequent meniscectomy, and was identified after cross-referencing data from the ACL Registry with the national database of the Accident Compensation Corporation (ACC). Multivariate Cox regression was performed to produce hazard ratios (HR) with 95% confidence intervals (CI) to identify the patient and surgical risk factors for meniscal repair failure. 2041 meniscal repairs were analyzed (medial = 1235 and lateral = 806). The overall failure rate was 9.4% (n = 192). Failure occurred in 11.1% of medial (137/1235) and 6.8% of lateral (55/806) meniscal repairs. The risk of medial failure was higher with hamstring tendon autografts (adjusted HR = 2.00, 95% CI 1.23 – 3.26, p = 0.006) and in patients with cartilage injury in the medial compartment (adjusted HR = 1.56, 95% CI 1.09 – 2.23, p = 0.015). The risk of lateral failure was higher when the procedure was performed by a surgeon with an annual case volume of less than 30 ACL reconstructions (adjusted HR = 1.92, 95% CI 1.10 – 3.33, p = 0.021). Age, gender, time from injury-to-surgery and femoral tunnel drilling technique did not influence the risk of meniscal repair failure. When repairing a meniscal tear during ACL reconstruction, the use of a hamstring tendon autograft or the presence of cartilage injury in the medial compartment increases the risk of medial meniscal repair failure. Lower surgeon case volume increases the risk of lateral meniscal repair failure

Screw fixation is an established method for anterior cruciate ligament (ACL) reconstruction, although with a high rate of implant-related complications. An allograft system for implant fixation in ACL reconstruction, the Shark Screw ACL (surgebright GmbH) could overcome some of the shortcomings of bioabsorbable screws, such as foreign body reaction, need for implant removal and imaging artefacts. However, it needs to provide sufficient mechanical stability. Therefore, the aim of this study was to investigate the biomechanical stability, especially graft slippage, of the novel allograft system versus a conventional bioabsorbable interference screw (BioComposite Interference Screw; Arthrex Inc.) for tibial implant fixation in ACL reconstruction. Twenty-four paired human proximal tibiae (3 female, 9 male, 72.7 ± 5.6 years) underwent ACL reconstruction. The quadrupled semitendinosus and gracilis tendon graft were fixed in one specimen of each pair using the allograft fixation system Shak Screw ACL and the contralateral one using an interference screw. All specimens were cyclically loaded at 1 Hz with peak load levels monotonically increased from 50 N at a rate of 0.1 N/cycle until catastrophic failure. Relative movements of the graft versus the tibia were captured with a stereographic optical motion tracking system (Aramis SRX; GOM GmbH). The two fixation methods did not demonstrate any statistical difference in ultimate load at graft slippage (p = 0.24) or estimated survival at slippage (p = 0.06). Both, the ultimate load and estimated survival until failure were higher in the interference screw (p = 0.04, and p = 0.018, respectively). Graft displacement at ultimate load reached values of up to 7.2 mm (interference screw) and 11.3 mm (Shark Screw ACL). The allograft screw for implant fixation in ACL reconstruction showed similar behavior in terms of graft slippage compared to the conventional metal interference screw but underperformed in terms of ultimate load. However, the ultimate load may not be considered a direct indicator of clinical failure

Background. Anterior cruciate ligament (ACL) reconstruction with concomitant meniscal injury occurs frequently. Meniscal repair is associated with improved long-term outcomes compared to resection but is also associated with a higher reoperation rate. Knowledge of the risk factors for repair failure may be important in optimizing patient outcomes. Purpose. This study aimed to identify the patient and surgical risk factors for meniscal repair failure, defined as a subsequent meniscectomy, following concurrent primary ACL reconstruction. Methods. Data recorded by the New Zealand ACL Registry and the Accident Compensation Corporation, the New Zealand Government's sole funder of ACL reconstructions and any subsequent surgery, was reviewed. Meniscal repairs performed with concurrent primary ACL reconstruction was included. Root repairs were excluded. Univariate and multivariate survival analysis was performed to identify the patient and surgical risk factors for meniscal repair failure. Results. Between 2014 and 2020, a total of 3,024 meniscal repairs were performed during concurrent primary ACL reconstruction (medial repair = 1,814 and lateral repair = 1,210). The overall failure rate was 6.6% (n = 201) at a mean follow-up of 2.9 years, with a failure occurring in 7.8% of medial meniscal repairs (142 out of 1,814) and 4.9% of lateral meniscal repairs (59 out of 1,210). The risk of medial failure was higher in patients with a hamstring tendon autograft (adjusted HR = 2.20, p = 0.001), patients aged 21–30 years (adjusted HR = 1.60, p = 0.037) and in those with cartilage injury in the medial compartment (adjusted HR = 1.75, p = 0.002). The risk of lateral failure was higher in patients aged ≤ 20 years (adjusted HR = 2.79, p = 0.021) and when the procedure was performed by a surgeon with an annual ACL reconstruction case volume of less than 30 (adjusted HR = 1.84, p = 0.026). Conclusion. When performing meniscal repair during a primary ACL reconstruction, the use of a hamstring tendon autograft, younger age and the presence of concomitant cartilage injury in the medial compartment increases the risk of medial meniscal repair failure, whereas younger age and low surgeon volume increases the risk of lateral meniscal repair failure

Anterior cruciate ligament (ACL) injuries have been increasing, especially amongst adolescents. These injuries can increase the risk for early-onset knee osteoarthritis (OA). The consequences of late-stage knee OA include structural joint change, functional limitations and persistent pain. Interleukin-6 (IL-6) is a pro-inflammatory biomarker reflecting knee joint healing, and increasing evidence suggests that IL-6 may play a critical role in the development of pathological pain. The purpose of this study was to determine the relationship between subjective knee joint pain and function, and synovial fluid concentrations of the pro-inflammatory cytokine IL-6, in adolescents undergoing anterior cruciate ligament reconstruction surgery. Seven youth (12-17 yrs.) undergoing anterior cruciate ligament (ACL) reconstruction surgery participated in this study. They completed the Pedi International Knee Documentation Committee (Pedi-IKDC) questionnaire on knee joint pain and function. At the time of their ACL reconstruction surgery, synovial fluid samples were collected through aspiration to dryness with a syringe without saline flushing. IL-6 levels in synovial fluid (sf) were measured using enzyme linked immunosorbent assay. Spearman's rho correlation coefficient was used to determine the correlation between IL-6 levels and scores from the Pedi-IKDC questionnaire. There was a statistically significant correlation between sfIL-6 levels and the Pedi-IKDC Symptoms score (-.929, p=0.003). The correlations between sfIL-6 and Pedi-IKDC activity score (.546, p = .234) and between sfIL-6 and total Pedi-IKDC score (-.536, p = .215) were not statistically significant. This is the first study to evaluate IL-6 as a biomarker of knee joint healing in an adolescent population, reported a very strong correlation (-.929, p=0.003) between IL-6 in knee joint synovial fluid and a subjective questionnaire on knee joint pain. These findings provide preliminary scientific evidence regarding the relationship between knee joint pain, as determined by a validated questionnaire and the inflammatory and healing status of the patient's knee. This study provides a basis and justification for future longitudinal research on biomarkers of knee joint healing in patients throughout their recovery and rehabilitation process. Incorporating physiological and psychosocial variables to current return-to-activity (RTA) criteria has the potential to improve decision making for adolescents following ACL reconstruction to reduce premature RTA thereby reducing the risk of re-injury and risk of early-onset knee OA in adolescents

Surgery performed in low-volume centres has been associated with longer operating time, longer hospital stays, lower functional outcomes, and higher rates of revision surgery, complications, and mortality. This has been reported consistently in the arthroplasty literature, but there is a paucity of data regarding the relationship between surgical volume and outcome following anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare the ACL reconstruction failure rate between hospitals performing different annual surgical volumes. The hypothesis was that ACL reconstructions performed at low-volume hospitals would be associated with higher failure rates than those performed at high-volume centres. This level-II cohort study included all patients from the Norwegian Knee Ligament Registry that underwent isolated primary autograft ACL reconstruction between 2004 and 2016. Hospital volume was divided into quintiles based on the number of ACL reconstructions performed annually, defined arbitrarily as: 1–12 (V1), 13–24 (V2), 25–49 (V3), 50–99 (V4), and ≥100 (V5) annual procedures. Kaplan-Meier estimated survival curves and survival percentages were calculated with revision ACL reconstruction as the end point. Mean change in Knee Injury and Osteoarthritis Outcome Score (KOOS) Quality of Life and Sport subsections from pre-operative to two-year follow-up were compared using t-test. 19,204 patients met the inclusion criteria and 1,103 (5.7%) underwent subsequent revision ACL reconstruction over the study period. Patients in the lower volume categories (V1-3) were more often male (58–59% vs. 54–55% p=<0.001) and older (27 years vs. 24–25 years, p=<0.001) compared to the higher volume hospitals (V4-5). Concomitant meniscal injuries (52% vs. 40%) and participation in pivoting sports (63% vs. 56%) were most common in V5 compared with V1 (p=<0.001). Median operative time decreased as hospital volume increased, ranging from 90 minutes at V1 hospitals to 56 minutes at V5 hospitals (p=<0.005). Complications occurred at a rate of 3.8% at low-volume (V1) hospitals versus 1.9% at high-volume (V5) hospitals (p=<0.001). Unadjusted 10-year survival with 95% confidence intervals for each hospital volume category were: V1 – 95.1% (93.7–96.5%), V2 – 94.1% (93.1–95.1%), V3 – 94.2% (93.6–94.8%), V4 – 92.6% (91.8–93.4%), and V5 – 91.9% (90.9–92.9%). There was no difference in improvement between pre-operative and two-year follow-up KOOS scores between hospital volume categories. Patients having ACL reconstruction at lower volume hospitals did not have inferior clinical or patient reported outcomes, and actually demonstrated a lower revision rate. Complications occurred more frequently however, and operative duration was longer. The decreased revision rate is an interesting finding that may be partly explained by the fact that patients being treated in these small, often rural hospitals, may be of lower demand as suggested by the increased age and decreased participation in pivoting sports. In addition, patients with more complicated pathology such as meniscal tears were more commonly treated in the larger volume hospitals. The most significant limitation of this study is that provider volume was not assessed, and the number of surgeons dividing up the surgical volume at each hospital is not known

Anterior cruciate ligament (ACL) injuries are among the most common and debilitating knee injuries in professional athletes with an incidence in females up to eight-times higher than their male counterparts. ACL injuries can be career-threatening and are associated with increased risk of developing knee osteoarthritis in future life. The increased risk of ACL injury in females has been attributed to various anatomical, developmental, neuromuscular, and hormonal factors. Anatomical and hormonal factors have been identified and investigated as significant contributors including osseous anatomy, ligament laxity, and hamstring muscular recruitment. Postural stability and impact absorption are associated with the stabilizing effort and stress on the ACL during sport activity, increasing the risk of noncontact pivot injury. Female patients have smaller diameter hamstring autografts than males, which may predispose to increased risk of re-rupture following ACL reconstruction and to an increased risk of chondral and meniscal injuries. The addition of an extra-articular tenodesis can reduce the risk of failure; therefore, it should routinely be considered in young elite athletes. Prevention programs target key aspects of training including plyometrics, strengthening, balance, endurance and stability, and neuromuscular training, reducing the risk of ACL injuries in female athletes by up to 90%. Sex disparities in access to training facilities may also play an important role in the risk of ACL injuries between males and females. Similarly, football boots, pitches quality, and football size and weight should be considered and tailored around females’ characteristics. Finally, high levels of personal and sport-related stress have been shown to increase the risk of ACL injury which may be related to alterations in attention and coordination, together with increased muscular tension, and compromise the return to sport after ACL injury. Further investigations are still necessary to better understand and address the risk factors involved in ACL injuries in female athletes. Cite this article: Bone Jt Open 2024;5(2):94–100

Summary:. Hamstring tendons (HT) represent a widely used autograft for ACL reconstruction. Harvesting, processing and pretensioning procedures together with the time out of the joint could theoretically hamper tendon cells (TCs) viability. The authors hypothesize that HT cells are not impaired at the end of the surgical procedures and their tenogenic phenotype may be strongly improved by exposure to PEMF. Methods. Remnants of semitendinosus and gracilis tendons were collected at the end of the surgical procedures before skin closure from 15 healthy donors who underwent ACL reconstruction with autologous hamstring tendons. To isolate TCs, the tendon was minced and digested with 0.3 % type I collagenase and the nucleated cells were plated at a density 5x10E3 cells/cm2 and cultured in chamber slides in differentiation medium composed of DMEM + 5ng/ml basic fibroblast growth factor (b-FGF) for 7, 14, 21 days. The following cell cultures were set up:. -. TCs cultured with differentiation medium + exposure to PEMF 8 h/day (PEMF generator system IGEA, intensity of magnetic field = 1.5 mT, frequency = 75 Hz). -. TCs cultured with differentiation medium without exposure to PEMF. At day 0, day 7, day 14 and day 21, immunofluorescence analysis was performed to evaluate the expression of collagen type I, collagen type VI, scleraxis and PCNA (proliferative marker). Subsequently, tendon explant cultures were set up to verify, at day 21, explant viability and the expression of collagen type I, collagen type VI, beta-catenin and PCNA. Results. The TCs from the tendon fragments at the end of the ACL reconstruction were alive and they expressed markers of proliferation and tendon phenotype at the end of the culture periods. The TCs in the presence PEMF 8h/day showed greater production of collagen type I, collagen type VI and scleraxis than that of TCs cultured without PEMF (p<0,05): the expression of this markers increased from 7 to 21 days of culture. The expression of PCNA, in the presence of PEMF stimulus, was significantly lower (p<0,05) than that of TCs cultured without PEMF. A similar behavior was surprisingly observed in tendon explant cultures. Conclusions. Hamstring tendons used for ACL reconstruction are not simple autologous tenoconductive scaffold but are a biologic structure rich in progenitor cells that show tenogenic behavior. Their tenogenic phenotype may be strongly improved by exposure to PEMF. In a future clinical perspective, the postoperative use of PEMF could be used to enhance the ligamentization processes of autologous hamstring tendons, when used as autografts for ACL reconstructions

The April 2024 Knee Roundup. 360. looks at: Challenging the status quo: re-evaluating the impact of obesity on unicompartmental knee arthroplasty outcomes; Timing matters: the link between ACL reconstruction delays and cartilage damage; Custom fit or off the shelf: evaluating patient outcomes in tailored versus standard knee replacements; Revolutionizing knee replacement: a comparative study on robotic-assisted and computer-navigated techniques; Pre-existing knee osteoarthritis and severe joint depression are associated with the need for total knee arthroplasty after tibial plateau fracture in patients aged over 60 years; Modern digital therapies?; A matched study on fracture rates following knee replacement surgeries;

Objectives. To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model. Methods. Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing. Results. Histologically, both groups showed a mixture of direct and indirect healing patterns at four weeks, whereas only indirect healing patterns were observed in both groups at eight weeks. No significant histological differences were seen between the two groups at four and eight weeks in the roof zone (four weeks, S: mean 4.8 . sd. 1.7, T: mean 4.5 . sd. 0.5, p = 0.14; eight weeks, S: mean 5.8 . sd. 0.8, T: mean 4.8 . sd. 1.8, p = 0.88, Mann-Whitney U test) or side zone (four weeks, S: mean 5.0 . sd. 1.2, T: mean 4.8 . sd. 0.4, p = 0.43; eight weeks, S: mean 5.3 . sd. 0.8,T: mean 5.5 . sd. 0.8, p = 0.61, Mann-Whitney U test) . Similarly, no significant difference was seen in the maximum failure load between group S and group T at four (15.6 . sd. 9.0N and 13.1 . sd. 5.6N) or eight weeks (12.6 . sd. 3.6N and 17.1 . sd. 6.4N, respectively). Conclusion. Regardless of bone tunnel configuration, tendon-bone healing after ACL reconstruction primarily occurred through indirect healing. No significant histological or mechanical differences were observed between adjustable and fixed-loop femoral cortical suspension methods. Cite this article: Y. Sato, R. Akagi, Y. Akatsu, Y. Matsuura, S. Takahashi, S. Yamaguchi, T. Enomoto, R. Nakagawa, H. Hoshi, T. Sasaki, S. Kimura, Y. Ogawa, A. Sadamasu, S. Ohtori, T. Sasho. The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018;7:327–335. DOI: 10.1302/2046-3758.75.BJR-2017-0238.R2

Aims. The aim of this study was to investigate the incidence, risk factors, and outcome of venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction in a nationwide cohort. Patients and Methods. All ACL reconstructions, primary and revision, that were recorded in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare. The incidence of VTE was determined by entries between the day of surgery until 90 days postoperatively based on diagnosis codes and the prescription of anticoagulants. Risk factors, outcome, and the use of thromboprophylaxis were analyzed. Descriptive statistics with multivariate analysis were used to describe the findings. Results. The cohort consisted of 26 014 primary and revision ACL reconstructions. There were 89 deep venous thromboses (DVTs) and 12 pulmonary emboli (PEs) with a total of 95 VTEs (0.4 %). Six patients with a PE had a simultaneous DVT. The only independent risk factor for VTE was age greater than or equal to 40 years (odds ratio 2.31, 95% confidence interval 1.45 to 3.70; p < 0.001). Thromboprophylaxis was prescribed to 9461 patients (36%) and was equally distributed between those with and those without a VTE (37.9% vs 36.4%). All patient-reported outcome measures (PROMs) one and two years postoperatively were significantly lower in those with VTE. Conclusion. The incidence of VTE following ACL reconstruction is 0.4%, and the only significant risk factor is age. Patients with VTE had worse postoperative clinical outcome than patients without VTE. We recommend against the routine use of thromboprophylaxis, but it should be considered in older patients

Abstract. Methodology. Prospective single-surgeon case-series evaluating patients undergoing surgery by this technique. 76 cases (mean age of 33.2 years) who had primary ACL reconstruction with BTB or quadriceps tendon with bone block, were divided into 2 matched groups (age, sex and type of graft) of 38 each based on the method of femoral fixation used (interference screw or adjustable cortical suspension). Patients were followed up clinically and using PROMS from NLR with EQ-5D, KOOS, IKDC and Tegner scores. Complications and return to theatre were noted. Paired two-tailed student t-tests and Chi-square tests were employed for statistical analysis. Results. At a mean follow-up of 82 months, peri-operative mean EQ-5D VAS, EQ-5D Index, KOOS, IKDC and Tegner activity scores showed significant improvement (p<0.05), but no significant difference between the two groups (p>0.05). Mean graft length and diameter was 77mm and 9.3 respectively. Mean interval from injury to surgery was 10.5 months. 18(23.7%) patients had associated meniscal tear with 73.3 % undergoing repair. 10 cases (13.2 %) returned to theatre including, MUA for arthrofibrosis (n=2) and intra-substance graft failure (n=2). 3 cases had to be converted to interference screw fixation due to the tightrope cutting through from the femoral bone block as a result of a technical pitfall. Conclusion. Primary ACL reconstruction using adjustable cortical suspension on femoral side for BTB or quadriceps bone-block tendon graft is a safe technique with added advantages of 360 degree bone ingrowth and no screw in the femoral tunnel

Introduction. Over the past 30 years multiple wars and embargos have reduced healthcare resources, infrastructure, and staff in Iraq. Subsequently, there are a lack of physiotherapists to provide rehabilitation after an anterior cruciate ligament reconstruction (ACLR). The implementation of home-based rehabilitation programmes may provide a potential solution to this problem. This study, set in in the Kurdistan region of Iraq, describes the epidemiology and outcomes of anterior cruciate ligament reconstruction (ACLR) followed by home-based rehabilitation alone. Methods. A cohort observational study of patients aged ≥ 16 years with an ACL rupture who underwent an ACLR under a single surgeon. This was performed arthroscopically using a hamstring autograft (2 portal technique). Patients completed a home-based rehabilitation programme of appropriate simplicity for the home setting. The programme consisted of stretching, range of motion and strengthening exercises based on criterion rehabilitation progressions. A full description of the programme is provided at: . https://ngmvcharity.co.uk/. . Demographics, mechanisms of injury, operative findings, and outcome data (Lysholm, Tegner Activity Scale (TAS), and revision rates) were collected from 2016 to 2021. Data were analysed using descriptive statistics. Results. The cohort consisted of 545 patients (547 knees), 99.6% were male with a mean age of 27.8 years (SD 6.18 years). The mean time from diagnosis to surgery was 40.6 months (SD 40.3). Despite data attrition Lysholm scores improved over the 15-month follow-up period, matched data showed the most improvement occurred within the first 2 months post-operatively. A peak score of 90 was observed at nine months. Post-operative TAS results showed an improvement in level of function but did not reach pre-injury levels by the final follow-up. At final follow-up, six (1.1%) patients required an ACLR revision. Conclusion. Patients who completed a home-based rehabilitation programme in Kurdistan had low revision rates and improved Lysholm scores 15 months post-operatively. To optimise resources, further research should investigate the efficacy of home-based rehabilitation for trauma and elective surgery in low- to middle-income countries and the developed world

Abstract. Purpose. Since arthroscopic reconstruction of the anterior cruciate ligament (ACL) started, the use of peroneus longus grafts for primary ACL reconstruction (ACLR) was never thought of as there is very scant literature on it. So, our study aims to compare the functional outcome and complications in patients with ACL injury managed by ACLR with peroneus longus tendon (PLT) and hamstring tendons (HT) respectively. Materials and Methods. Patients with 16–50 years of either gender presenting with symptomatic ACL deficiency were admitted for arthroscopic single bundle ACLR and allocated into two groups (PLT and HT) operated and observed. Functional scores (IKDC and Lysholm score), clinical knee evaluation, donor site morbidity (AOFAS score) and thigh circumference were recorded preoperatively and at six months, one year post-operatively. The same post-op rehabilitation protocol was followed in both groups. Results. 194 patients (hamstring n=96, peroneus n=98) met the inclusion criteria. There were no significant differences between the pre-op, six months post-op and one-year postoperative score between the hamstring and peroneus longus groups in the IKDC (p=0.356) and Lysholm knee score (p=0.289). The mean for the AOFAS was 99.05±3.56 and 99.80±0.70 in the PLT and HT group respectively showing no statistical difference, with a significant improvement in thigh muscle wasting among the PLT group at final follow-up (p<0.001). Conclusion. We observed similar knee stability, functional outcome and no obvious donor site morbidity among both groups and recommend that a PL graft may be a safe, effective, and viable option for arthroscopic single bundle ACL reconstruction

The optimal method of tibial fixation when using a hamstring tendon autograft in anterior cruciate ligament (ACL) reconstruction is unclear. This study aimed to compare the risk of revision ACL reconstruction between suspensory and interference devices on the tibial side. Prospective data on primary ACL reconstructions recorded in the New Zealand ACL Registry between April 2014 and December 2019 were analyzed. Only patients with a hamstring tendon autograft fixed with a suspensory device on the femoral side were included. The rate of revision ACL reconstruction was compared between suspensory and interference devices on the tibial side. Univariate Chi-Square test and multivariate Cox regression was performed to compute hazard ratios (HR) and 95% confidence intervals (CI) with adjustment for age, gender, time-to-surgery, activity at the time of injury, number of graft strands and graft diameter. 6145 cases were analyzed, of which 59.6% were fixed with a suspensory device on the tibial side (n = 3662), 17.6% fixed with an interference screw with a sheath (n = 1079) and 22.8% fixed with an interference screw without a sheath (n = 1404). When compared to suspensory devices (revision rate = 3.4%), a higher risk of revision was observed when using an interference screw with a sheath (revision rate = 6.2%, adjusted HR = 2.05, 95% CI 1.20 – 3.52, p = 0.009) and without a sheath (revision rate = 4.6%, adjusted HR = 1.81, 95% CI 1.02 – 3.23, p = 0.044). The number of graft strands and a graft diameter of ≥8 mm did not influence the risk of revision. When reconstructing the ACL with a hamstring tendon autograft, the use of an interference screw, with or without a sheath, on the tibial side has a higher risk of revision when compared to a suspensory device

Introduction: Number of patients needing revision ACL surgery has increased more than 10 fold. Results of revision surgery are traditionally thought to be inferior to primary reconstruction. Aim of this paper is to describe results of revision surgery using a two-stage technique and compare it with results of primary ACL reconstruction. Materials and Methods: We studied 44 consecutive patients with revision ACL surgery. They had 10 ACL reconstruction elsewhere using autologous (34) or prosthetic ligament (10). Rrevision surgery was two staged. First of debridement and bone grafting and second stage after 3 mths of meniscal and chondral work along with ACL reconstruction using autograft. We compared this group with a similar cohort of patients with primary ACL surgery. Conclusions: A two-stage revision technique for revision ACL surgery allows accurate assessment & opportunity for the bone graft to heal to provide good bed for graft fixation at the time of second procedure

Introduction. To evaluate career length after surgical treatment of combined ACL + medial collateral ligament (MCL) and ACL +posterolateral corner (PLC) surgeries in all elite athletes. Secondly, in a subgroup of male professional footballers to determine career length and competition level after ACL+MCL or ACL+PLC reconstructions and compare this to a cohort who underwent isolated ACL reconstruction (ACL-R) alone. Methods. A consecutive cohort of elite athletes undergoing combined ACL+MCL surgery and combined ACL+PLC surgery between February 2001 and October 2019 were analysed. A subgroup of male footballers from this population was compared to a previously identified cohort of male, professional footballers having had primary ACL reconstruction without other ligament surgery. A minimum 2-years follow-up was required. Outcome measures were career length and competition level. Results. Ninety-eight elite athletes were included, 50 had ACL+PLC and 48 had ACL+MCL surgeries. The timeline for return to play (RTP)was significantly longer for ACL+PLC injuries (12.8 months) as compared to ACL+MCL injuries (11.1 months, p=.019). On average, career length after surgery of an athlete in the ACL+PLC group was 4.8 years and for the ACL+MCL group 4.2 years (n.s.). In the subgroup analysis of footballers, a significantly lower number of players with combined ACL+PLC surgery were able to RTP (88%, p=.003) compared to 100%for ACL+MCL surgery and 97% for isolated ACL reconstruction, as well as requiring almost 3 months longer RTP timeline (12.9±4.2 months= .002) when compared to isolated ACL (10.2 ± 3.9 months) and combined ACL+MCL groups (10.0+2.4 months). However, career length and competition level were not significantly different between groups. Conclusion. The addition of MCL surgery to ACL-R did not affect RTP time and rate in elite athletes, nor competition level in male professional footballers compared to ACL-R alone. Moreover, the career length after successful RTP following combined ACL+MCL or ACL+PLC surgeries were the same. However, professional footballers with combined ACL+PLC surgery return at a lower rate and require a longer RTP time when compared to the ones with isolated ACL-R or combined ACL+MCL surgery. For the factors assessed in this study additional MCL surgery to ACL-R alone did not alter outcome from that with ACL-R in professional soccer players

The bone-patellar tendon-bone (BTB) autograft is associated with difficulty kneeling following anterior cruciate ligament (ACL) reconstruction, however it is unclear whether it results in a more painful or symptomatic knee when compared to the hamstring tendon autograft. This study aimed to identify the rate of significant knee pain and difficulty kneeling following primary ACL reconstruction and clarify whether graft type influences the risk of these complications. Primary ACL reconstructions prospectively recorded in the New Zealand ACL Registry between April 2014 and November 2019 were analyzed. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was analyzed to identify patients who reported significant knee pain, defined as a KOOS Pain subscale score of ≤72 points, and kneeling difficulty, defined as a patient who reported “severe” or “extreme” difficulty when they kneel. The rate of knee pain and kneeling difficulty was compared between graft types via univariate Chi-square test and multivariate binary logistic regression with adjustment for patient demographics. 4492 primary ACL reconstructions were analyzed. At 2-year follow-up, 9.3% of patients reported significant knee pain (420/4492) and 12.0% reported difficulty with kneeling (537/4492). Patients with a BTB autograft reported a higher rate of kneeling difficulty compared to patients with a hamstring tendon autograft (21.3% versus 9.4%, adjusted odds ratio = 3.12, p<0.001). There was no difference between graft types in the rate of significant knee pain (9.9% versus 9.2%, p = 0.49) or when comparing absolute values of the KOOS Pain (mean score for BTB = 88.7 versus 89.0, p = 0.37) and KOOS Symptoms subscales (mean score for BTB = 82.5 versus 82.1, p = 0.49). The BTB autograft is a risk factor for post-operative kneeling difficulty, but it does not result in a more painful or symptomatic knee when compared to the hamstring tendon autograft

Aims. To evaluate graft healing of decellularized porcine superflexor tendon (pSFT) xenograft in an ovine anterior cruciate ligament (ACL) reconstruction model using two femoral fixation devices. Also, to determine if pSFT allows functional recovery of gait as compared with the preoperative measurements. Methods. A total of 12 sheep underwent unilateral single-bundle ACL reconstruction using pSFT. Two femoral fixation devices were investigated: Group 1 (n = 6) used cortical suspensory fixation (Endobutton CL) and Group 2 (n = 6) used cross-pin fixation (Stratis ST). A soft screw was used for tibial fixation. Functional recovery was quantified using force plate analysis at weeks 5, 8, and 11. The sheep were euthanized after 12 weeks and comprehensive histological analysis characterized graft healing at the graft-bone interface and the intra-articular graft (ligamentization). Results. The pSFT remodelled into a ligament-like structure and no adverse inflammatory reaction was seen. The ground reaction force in the operated leg of the Endobutton group was higher at 11 weeks (p < 0.05). An indirect insertion was seen at the graft-bone interface characterized by Sharpey-like fibres. Qualitative differences in tendon remodelling were seen between the two groups, with greater crimp-like organization and more aligned collagen fibres seen with Endobutton fixation. One graft rupture occurred in the cross-pin group, which histologically showed low collagen organization. Conclusion. Decellularized pSFT xenograft remodels into a ligament-like structure after 12 weeks and regenerates an indirect-type insertion with Sharpey-like fibres. No adverse inflammatory reaction was observed. Cortical suspensory femoral fixation was associated with more enhanced graft remodelling and earlier functional recovery when compared with the stiffer cross-pin fixation

Between 1993 and 1994, 891 patients underwent primary anterior cruciate ligament (ACL) reconstruction. A total of 48 patients had undergone bilateral ACL reconstruction and 42 were available for review. These patients were matched to a unilateral ACL reconstruction control group for gender, age, sport of primary injury, meniscal status and graft type. At 15-year follow-up a telephone interview with patients in both groups was performed. The incidence of further ACL injury was identified through structured questions and the two groups were compared for the variables of graft rupture or further ACL injury, family history of ACL injury, International Knee Documentation Committee (IKDC) subjective score and activity level. There were 28 male and 14 female patients with a mean age of 25 years (13 to 42) at the time of first ACL injury. Subsequent further ACL injury was identified in ten patients (24%) in the bilateral ACL reconstruction study group and in nine patients (21%) in the unilateral ACL reconstruction control group (p = 0.794). The mean time from bilateral ACL reconstruction to further ACL injury was 54 months (6 to 103). There was no significant difference between the bilateral ACL reconstruction study group and the matched unilateral ACL reconstruction control group in incidence of further ACL injury (p = 0.794), family history of ACL injury (p = 0.595), IKDC activity level (p = 0.514), or IKDC subjective score (p = 0.824). After bilateral ACL reconstruction the incidence of graft rupture and subjective outcomes were equivalent to that after unilateral ACL reconstructions. Cite this article: Bone Joint J 2013;95-B:798–802

The purpose of this study was to determine whether the reasons for delay to surgery are secondary to health system constraints or patient factors. This study explored factors that contribute to patients' delay to surgery as well as how patients perceive the delay in surgery to have affected their treatment and care. Semi-structured qualitative interviews were conducted with 30 patients aged 18 to 50 years old who had undergone arthroscopic ACL reconstruction. Qualitative data analysis was performed in accordance with the Straus and Corbin theory to derive codes, categories and themes. Patient interviews revealed three overarching themes regarding delay to ACL reconstruction surgery: access to care, finances and work, and personal advocacy. Elements of those factors were shown to influence the timing of ACL reconstruction surgery. Less common factors included choice of imaging study (i.e., ultrasound), geography, and family commitments. Patients' perceptions of delay in access to care was overwhelming due to the wait time for MRI. Several patients also described significant self-advocacy required to navigate the healthcare system, suggesting that some level of medical literacy may be necessary to gain timely access to surgery. Once patients had seen the surgeon, few patients described untimely delay to surgery, suggesting that OR resources are adequate. Recommendations to decrease delays to ACL reconstruction surgery include better access to MRI and broader education of non-surgical healthcare providers to help navigate access to surgery

The treatment of medial knee osteoarthritis (OA) in conjunction with anterior knee laxity is an issue of debate. Current treatment options include knee joint distraction, unicompartmental knee replacement (UKR) or high tibial osteotomy with anterior cruciate ligament (ACL) reconstruction or total knee replacement. Bone-conserving options are preferred for younger and active patients with intact lateral and patello-femoral compartment. However, still limited experience exists in the field of combining medial UKR and ACL reconstruction. The aim of this study is to retrospectively evaluate the results of combined fixed-bearing UKR and ACL reconstruction, specifically with regard to patient satisfaction, activity level, and postoperative functional outcomes. The hypothesis was that this represents a safe and viable procedure leading to improved stability and functional outcome in patients affected by isolated unicompartmental OA and concomitant ACL deficiency. Fourteen patients with ACL deficiency and concomitant medial compartment symptomatic osteoarthritis were treated from 2006 to 2010. Twelve of them were followed up for an average time of 7.8 year (range 6–10 years). Assessment included Knee Osteoarthritis Outcome Score (KOOS), Oxford Knee score (OKS), American Knee Society scores (AKSS), WOMAC index of osteoarthritis, Tegner activity level, objective examination including instrumented laxity test with KT-1000 arthrometer and standard X-rays. Wilcoxon test was utilized to compare the pre-operative and follow-up status. Differences with a p value <0.05 were considered statistically significant. KOOS score, OKS, WOMAC index and the AKSS improved significantly at follow-up (p < 0.05). There was no clinical evidence of instability in any of the knees as evaluated with clinical an instrumented laxity testing (p < 0.05). No pathologic radiolucent lines were observed around the components. In one patient a total knee prosthesis was implanted due to the progression of signs of osteoarthritis in the lateral compartment 3 years after primary surgery. UKR combined with ACL reconstruction is a valid therapeutic option for young and active patients with a primary ACL injury who develop secondary OA and confirms subjective and objective clinical improvement up to 8 years after surgery

Introduction. It has been contentious whether an anatomic double-bundle technique for anterior cruciate ligament reconstruction (ACLR)is superior to that of a single-bundle technique. It has been hypothesized in the literature that the double-bundle technique could provide function closer to that of the anatomical knee joint. The purpose of this study was to compare the long-term clinical outcomes after single-bundle ACLR versus double-bundle ACLR. We hypothesized that the double-bundle technique would not be superior to the single-bundle technique. Methods. A retrospective, non-randomized, matched-paired comparative study was performed. Patients undergoing primary anterior cruciate ligament reconstruction, using either a double-bundle or single-bundle technique, between 2003 and 2008 were included and matched 1:1. Matching included age, sex, BMI, time from injury to surgery, side of injury and type of sport. Patients who underwent revision procedures, multiligament reconstruction or other ACLR techniques were excluded. Patients were subsequently followed up, noting occurrence of graft rupture and any other complications. Results. A total of 1377 ACLRs were performed during the study period. Seven hundred and fifty-six patients were excluded, leaving 396patients to be included in the matching (198 matched pairs). Mean follow-up time was 176.7 +/− 7.7 months (range, 166–211 months). Overall, 40 patients (10.1%) suffered from a graft rupture which consisted of 22 patients (11.1%) in the single-bundle group and 18patients (9.1%) in the double-bundle group. A multivariate analysis was performed using the Cox model and demonstrated that graft failure had no significant association with the surgical technique (hazard ratio (HR), 0.857(0.457;1.609), p=0.6313). (Figure 1) Five patients (2.5%) in the single-bundle group and 7 patients (3.5%) in the double-bundle group underwent secondary surgery for cyclops syndrome(p=0.5637). Three patients (1.5%) in the single-bundle group and 2 patients (1.0%) in the double-bundle group underwent arthrolysis(p=0.6547). Seven patients (3.5%) in the single-bundle group underwent secondary meniscectomy compared to 6 patients (3.0%) in the double-bundle group (p=0.7630). Conclusion. Double-bundle ACLR is not superior to single-bundle ACLR at long-term follow up. Therefore, orthopaedic surgeons do not need to use a double-bundle technique when performing ACL reconstruction. For any figures or tables, please contact authors directly

Following anterior cruciate ligament reconstruction (ACLR) using a semitendinosus (ST) autograft measures such as length, cross-sectional area, and volume may not fully describe the effects of tendon harvest on muscle morphology as these discrete measures cannot characterize three-dimensional muscle shape. This study aimed to determine between-limb ST shape similarity and regional morphology in individuals with a unilateral history of ACLR using a ST graft, and healthy controls. A secondary analysis of magnetic resonance imaging was undertaken from 18 individuals with unilateral history of ST ACLR and 18 healthy controls. ST muscles were manually segmented, and shape similarity were assessed between limbs and groups using Jaccard index (0-1) and Hausdorff distance (mm). ST length (cm), peak cross-sectional area (CSA) (cm. 2. ), and volume (cm. 3. ) was compared between surgically reconstructed and uninjured contralateral limbs, and between the left and right limbs of control participants with no history of injury. Cohen's d was reported as a measure of effect size. Compared to healthy controls, the ACLR group had significantly (p<0.001, d= −2.33) lower bilateral ST shape similarity. Furthermore, the deviation in muscle shape was significantly (p<0.001, d= 2.12) greater in the ACLR group. Within the ACLR group, maximum Hausdorff distance indicated ST from the ACLR limb deviated (23.1±8.68 mm) from the shape of the healthy contralateral ST, this was observed particularly within the distal region of the muscle. Compared to the uninjured contralateral limb and healthy controls, deficits in peak cross-sectional area and volume in ACLR group were largest in proximal (p<0.001, d= −2.52 to −1.28) and middle (p<0.001, d= −1.81 to −1.04) regions. Findings highlight morphological features in distal ST not identified by traditional discrete morphology measures. ST shape was most different in the distal region of the muscle, despite deficits in CSA and volume being most pronounced in proximal and middle regions. ST shape following ACLR may affect force transmission and distribution within the hamstrings and contribute to persistent deficits in knee flexor and internal rotator strength

The objective of this study was to analyze the biomechanical effect of an implanted ACL graft by determining the tunnel position according to the aspect ratio (ASR) of the distal femur during flexion-extension motion. To analyze biomechanical characteristics according to the ASR of the knee joint, only male samples were selected to exclude the effects of gender and 89 samples were selected for measurement. The mean age was 50.73 years, and the mean height was 165.22 cm. We analyzed tunnel length, graft bending angle, and stress of the graft according to tunnel entry position and aspect ratio (ratio of antero-posterior depth to medio-lateral width) of the articular surface for the distal femur during single-bundle outside-in anterior cruciate ligament reconstruction surgery. We performed multi-flexible-body dynamic analyses with wherein four ASR (98, 105, 111, and 117%) knee models. The various ASRs were associated with approximately 1-mm changes in tunnel length. The graft bending angle increased when the entry point was far from the lateral epicondyle and was larger when the ASR was smaller. The graft was at maximum stress, 117% ASR, when the tunnel entry point was near the lateral epicondyle. The maximum stress value at a 5-mm distance from the lateral epicondyle was 3.5 times higher than the 15-mm entry position and, the cases set to 111% and 105% ASR, showed 1.9 times higher stress values when at a 5-mm distance compared with a 15-mm distance. In the case set at 98% ASR, the low-stress value showed a without-distance difference from the lateral epicondyle. Our results suggest that there is no relationship between the ASR and femoral tunnel length, A smaller ASR causes a higher graft bending angle, and a larger ASR causes greater stress in the graft

Anterior cruciate ligament reconstruction (ACLR) using a semitendinosus (ST) autograft, with or without gracilis (GR), results in donor muscle atrophy and varied tendon regeneration. The effects of harvesting these muscles on muscle moment arm and torque generating capacity have not been well described. This study aimed to determine between-limb differences (ACLR vs uninjured contralateral) in muscle moment arm and torque generating capacity across a full range of hip and knee motions. A secondary analysis of magnetic resonance imaging was undertaken from 8 individuals with unilateral history of ST-GR ACLR with complete ST tendon regeneration. All hamstring muscles and ST tendons were manually segmented. Muscle length (cm), peak cross-sectional area (CSA) (cm. 2. ), and volume (cm. 3. ) were measured in ACLR and uninjured contralateral limbs. OpenSim was used to simulate and evaluate the mechanical consequences of changes in normalised moment arm (m) and torque generating capacity (N.m) between ACLR and uninjured contralateral limbs. Compared to uninjured contralateral limbs, regenerated ST tendon re-insertion varied proximal (+) (mean = 0.66cm, maximum = 3.44cm, minimum = −2.17cm, range = 5.61cm) and posterior (+) (mean = 0.38cm maximum = 0.71cm, minimum = 0.02cm, range = 0.69cm) locations relative to native anatomical positions. Compared to uninjured contralateral limbs, change in ST tendon insertion point in ACLR limbs resulted in 2.5% loss in peak moment arm and a 3.4% loss in peak torque generating capacity. Accounting for changes to both max isometric force and ST moment arm, the ST had a 14.8% loss in peak torque generating capacity. There are significant deficits in ST muscle morphology and insertion points following ST-GR ACLR. The ST atrophy and insertion point migration following ACLR may affect force transmission and distribution within the hamstrings and contribute to persistent deficits in knee flexor and internal rotator strength

Aims. Proliferation, migration, and differentiation of anterior cruciate ligament (ACL) remnant and surrounding cells are fundamental processes for ACL reconstruction; however, the interaction between ACL remnant and surrounding cells is unclear. We hypothesized that ACL remnant cells preserve the capability to regulate the surrounding cells’ activity, collagen gene expression, and tenogenic differentiation. Moreover, extracorporeal shock wave (ESW) would not only promote activity of ACL remnant cells, but also enhance their paracrine regulation of surrounding cells. Methods. Cell viability, proliferation, migration, and expression levels of Collagen-I (COL-I) A1, transforming growth factor beta (TGF-β), and vascular endothelial growth factor (VEGF) were compared between ACL remnant cells untreated and treated with ESW (0.15 mJ/mm. 2. , 1,000 impulses, 4 Hz). To evaluate the subsequent effects on the surrounding cells, bone marrow stromal cells (BMSCs)’ viability, proliferation, migration, and levels of Type I Collagen, Type III Collagen, and tenogenic gene (Scx, TNC) expression were investigated using coculture system. Results. ESW-treated ACL remnant cells presented higher cell viability, proliferation, migration, and increased expression of COL-I A1, TGF-β, and VEGF. BMSC proliferation and migration rate significantly increased after coculture with ACL remnant cells with and without ESW stimulation compared to the BMSCs alone group. Furthermore, ESW significantly enhanced ACL remnant cells’ capability to upregulate the collagen gene expression and tenogenic differentiation of BMSCs, without affecting cell viability, TGF-β, and VEGF expression. Conclusion. ACL remnant cells modulated activity and differentiation of surrounding cells. The results indicated that ESW enhanced ACL remnant cells viability, proliferation, migration, and expression of collagen, TGF-β, VEGF, and paracrine regulation of BMSC proliferation, migration, collagen expression, and tenogenesis. Cite this article: Bone Joint Res 2020;9(8):457–467

Young, active patients with end-stage medial osteoarthritis (OA) secondary to anterior cruciate ligament (ACL) deficiency present a treatment challenge for surgeons. Current surgical treatment options include high tibial osteotomy (HTO) with or without ACL reconstruction, unicompartmental knee arthroplasty (UKA) with ACL reconstruction, and total knee arthroplasty (TKA). A recent systematic review reported a much higher rate of complications in HTO combined with ACL reconstruction than with UKA-ACL (21.1% vs 2.8%), while survivorship between the two procedures was similar. UKA offers several advantages over TKA, namely faster recovery, lower blood loss, lower rate of postoperative complications, better range of motion, and better knee kinematics. However, UKA has classically been contraindicated in the presence of ACL deficiency due to reported concerns over increased incidence aseptic loosening tibia. However, as a majority of patients presenting with this pathology are young and active, concerns about implant longevity with TKRA and loss of bone stock have arisen. As a result, several authors have described combining ACL reconstruction with medial UKA to decrease the tibiofemoral translation-related stress on the tibial component, thereby decreasing aseptic loosening-related failures. The purpose of this study was to compare the functional outcomes and survivorship of combined medial UKA and ACL reconstruction (UKA-ACL) with those of a matched TKA cohort. We hypothesized that UKA-ACL patients would have better functional outcomes than TKA patients while maintaining similar survivorship. Material and Methods. We conducted a case-control study establishing UKA-ACL as the study group and TKA as the control group by a single senior surgeon between October 2005 and January 2015. We excluded patients who were over the age of 55 at the time of surgery and those who had less than two-year follow-up. A total of 21 patients (23 knees) were ultimately included in each group. Propensity matching was for age-, sex-, and body mass index (BMI)-matched control group of TKA cases. Surgical technique. UKA-ACL. This patient's had an arthroscopy to allow for tunnel preparation in the standard fashion and then the graft was passed and fixed on the femoral side. An MIS medial incision was then made to allow for insertion of the Oxford mobile-bearing unicompartmental prosthesis (Zimmer Biomet, Warsaw, IN). Primary choice of ACL graft was autogenous ipsilateral semitendinosus and gracilis tendons, which was available I and 6 of the cases were revision from previous Gore-Tex synthetic ligament reconstruction. Results. Preoperatively, baseline questionnaires demonstrated that the TKA group had scored significantly lower on the symptom subscore of the KOOS. There was no difference between the groups in the rest of the KOOS subscores, (the UCLA, and the Tegner. All scores (UCLA, and Tegner – TBC post stats) improved significantly after surgery in both groups. Improvement in each subscore of the KOOS surpassed the minimal clinically important difference in both the UKA-ACL and TKA groups. At latest follow-up, there was no significant difference between the groups on the KOOS, UCLA or Tegner, showing that our UKA-ACL patients fared as our TKA patients. This confirms that UKA-ACL is an important tool in dealing with young patients with end-stage medial OA and ACL deficiency and offers an option that leads to less bone loss and potentially easier future revision. For any figures or tables, please contact authors directly

Abstract. Introduction. Anterior cruciate ligament reconstruction (ACLR) can be performed with a number of different autografts including all soft tissue quadriceps autograft. (QT). QT has several advantages including decreased donor site morbidity, reduced anterior knee pain and comparable revision rates compared to other autografts. The primary aim of this review was to assess all complications of QT in adult population. Methodology. A systematic review of the literature was conducted on in accordance with the PRISMA guidelines using the online databases Medline and EMBASE. Clinical studies or reporting on soft tissue QT were included and appraised using the Methodological Index for Non-Randomized Studies (MINORS) tool. Results. Twelve studies were eligible, giving a total of 774 cases of QT ACLR. The mean age ranged from 18 to 45 years. The mean follow-up ranged from 12 to 55.6 months. Nine studies report on patients’ functional outcomes with mean IKDC score was 90.9 ±22.6 and Lysholm score of 88.6 ±6.5. Seven studies reported on complications which was overall 12.3% including 4.1% for graft site morbidity. Infection was reported in 0.4% of the patients. Seven studies reported on failure rate which was reported in 5.3%. Re-operation rate for any reason was 3.2 %. Conclusion. All soft tissue QT for ACLR has a low complication rate and revision rate. There is less graft site morbidity

Abstract. Introduction. The study aims were to demonstrate rates, level, and time taken to RTP in elite sports after ACL reconstruction (ACL-R) and compare football and rugby. Methods. A retrospective review of a consecutive series of ACL-R between 2005 and 2019 was undertaken. Patients were included if they were elite athletes and were a minimum of 2 years post primary autograft ACL-R. The outcomes measured were return to play (RTP), (defined as participation in a professional match or in national/ international level amateur competition), time to RTP after surgery, and RTP level (Tegner score). Results. Three hundred and ninety four elite athletes with 420 ACL-Rs (235 in footballers, 125 in rugby players and 60 in other sports) were included. 95.7% of all athletes returned to competition at a mean of 10.3 months after ACL-R with 90.1% at the same / higher level. There was no difference in RTP rates between rugby and football. Rugby players RTP faster than footballers (9.6 vs 10.6 months, (p=0.027). Overall re-rupture rate within 2 years was 6.4% but not significantly different between football (8.1%) and rugby (7.2%). Footballers were more likely to rupture their ACL during jumping / landing manoeuvres and to receive a PT graft than rugby players. There were no significant differences between football and rugby regarding patient characteristics, intraoperative findings and re-operation rates. Conclusion. Over 95% of all elite athletes RTP after primary ACL-R with 90% able to play at the same level. Rugby players RTP significantly faster than footballers

Abstract. Introduction. The aim of this study was to determine which factors affect a professional footballer's return to play performance level after ACL reconstruction (ACL-R). Additionally, to report their playing performance at 2 and 5 years post ACL-R compared to their preinjury performance. Methods. A retrospective review of a consecutive series of primary ACL-R undertaken in professional footballers between 2005 and 2019 was undertaken. Performance was determined by the number of minutes played and the league level compared to their pre-injury baseline. Playing time (minutes) was classified as same (within 20%), more, or less playing time for each season compared to the one year prior to surgery. Results. Two hundred footballers (mean age 24.1 ± 4.2 years) were included. 194 (97%) returned to professional football. At 2-years after ACL-R 61% of footballers were playing in the same/ higher league, 29% were playing in a lower league and 10% were not playing. At 5-years this was 35%, 37% and 28% respectively. Forty-six percent of footballers were playing the same or more minutes as pre-injury at 2 years post-surgery, 51% were at 3 and 4 years but this reduced to 45% at 5 years. The presence of >50% thickness chondral pathology, ACL-R lacking lateral extra-articular tenodesis and age over 25 years at surgery were all significant risk factors of worse performance rates after ACL-R. Conclusion. While professional footballers achieved high initial RTP rates after ACL-R, with the majority returning to pre-operative levels of competition, significant decreases in performance rates were noted over time

Abstract. Introduction. The use of MCL “pie-crusting” (selective release of the superficial MCL) to improve arthroscopic access to the posteromedial compartment of the knee for isolated meniscal surgery has been demonstrated. However, there are concerns that MCL pie-crusting with concomitant ACL reconstruction (ACLR) might affect knee stability and outcomes postoperatively. The aim of this study was to compare the functional outcomes between patients who underwent MCL pie-crusting at ACLR with those that did not. Methods. We performed a retrospective review of prospectively collected data from on the National Ligament Registry. 55 patients (33 male and 22 female) who had MCL pie-crusting(PC group) to address a meniscal lesion at the time of ACLR were compared with 65 patients (38 male and 27 female) who underwent isolated primary ACLR. All procedures were performed by a single surgeon at a tertiary centre between October 2013 and March 2019. Results. The mean Follow up was 4.2 years(range 2- 7 years). The mean EQ 5D- VAS scores were 82 and 81 in the PC group and ACLR only group respectively. The mean IKDC scores were 81 and 85 in the PC group and ACLR only group respectively. The mean KOOS scores in the PC group and ACLR only group were: Symptoms (81,87); Pain (89,92); ADLs (94,96), sports and recreation function (81,83), QoL (75,78) respectively. The differences in the scores were not statistically significant. Conclusions. This study demonstrates that pie-crusting of the MCL at the time of ACLR does not significantly affect the functional outcomes

Abstract. Background. Performing lateral extra-articular tenodesis (LET) with ACL reconstruction may conflict with the ACLR femoral tunnel. Methods. 12 fresh-frozen cadaveric knees were used: at 120 flexion, an 8mm ACLR femoral tunnel was drilled in the anteromedial bundle position via the anteromedial portal. A modified Lemaire LET was performed using a 1 cm-wide iliotibial band strip left attached to Gerdy's tubercle. The LET femoral fixation point was identified 10mm proximal / 5 mm posterior to the LCL femoral attachment, and a 2.4-mm guide wire was drilled, aiming at 0, 10, 20, or 30 degrees anteriorly in the axial plane, and at 0, 10, or 20 degrees proximally in the coronal plane. The relationship between the LET drilling guide wire and the ACLR femoral tunnel reamer was recorded for each combination. When collision with the femoral tunnel was recorded, the LET wire depth was measured. Results. Tunnel conflict occurred at a mean LET wire depth of 23.6 mm (15–33 mm). No correlation existed between LET wire depth and LET drilling orientation (r=0.066; p=0.67). Drilling angle in the axial plane was significantly associated with the occurrence of tunnel conflict (P < .001). However, no such association was detected when comparing the drilling angle in the coronal plane (P=0.267). Conclusion. Conflict occurred at as little as 15 mm depth. When longer implants are used, the orientation should be at least 30 degrees anterior in the axial plane. Clinical Relevance. This study provides important information for surgeons performing LET in combination with ACLR

The aim of this study was to determine Anterior Cruciate Ligament (ACL) graft and contralateral ACL (CACL) survival in patients who have undergone ACL reconstruction (ACLR) with hamstring autograft following netball injuries, and determine factors associated with repeat ACL injury and return to netball. From a prospectively collected database, a consecutive series of 332 female netballers who underwent primary ACLRs using hamstring autografts were identified. Subjects were surveyed at a minimum of five years following reconstruction, including details of further ACL injuries to either knee, return to netball or other sports and psychological readiness with the ACL-RSI score. 264 participants (80%) were reviewed at the mean follow up of 9 years (60-180 months). There were 12 ACL graft ruptures (5%) and 35 contralateral ACL ruptures (13%). ACL graft survival was 97% and 97%, 96% at 2, 5 and 7 years respectively. CACL survival was 99%, 94%, and 90% at 2, 5 and 7 years respectively. The 7-year ACL graft survival was 97% in those 25 or more and 93% in those under 25 years (p=0.126). The 7-year CACL survival was 93% in those 25 or more and 85% in those under 25 years (HR 2.6, 95%CI 1.3-5.0, p=0.007). A family history of ACL injury was reported by 32% of participants. A return to netball was reported by 61% of participants. The mean ACL-RSI score was 65 in those who returned to netball and 37 in those who did not (p=0.001). ACLR with hamstring autografts is a reliable procedure for netballers with a survival rate of 96% at 7 years, allowing 63% of participants to return to netball. A successful return to sport was associated with greater psychological readiness. CACL injury occurred with more than double the frequency of ACL graft rupture and was increased by 2.6x in those <25 years

To document and assess the available evidence regarding single bundle, hamstrings autograft preparation techniques for Anterior Cruciate Ligament reconstruction (ACLR) and provide graft preparation options for different clinical scenarios. Three online databases (Embase, PubMed and Ovid [MEDLINE]) were searched from database inception until April 10, 2021. The inclusion criteria were English language studies, human studies, and operative technique studies for single bundle hamstrings autograft preparation for ACLR. Descriptive characteristics, the number of tendons, number of strands, tendon length, graft length and graft diameter were recorded. The methodological quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) instrument and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system for non-randomized and randomized studies, respectively. The initial search yielded 5485 studies, 32 met the inclusion criteria. The mean MINORS score across all nonrandomized studies was 8.2 (standard deviation, SD 6.6) indicating an overall low quality of evidence. The mean MINORS score for comparative studies was 17.4 (SD 3.2) indicating a fair quality of evidence. The GRADE assessment for risk of bias in the randomized study included was low. There were 2138 knees in 1881 participants, including 1296 (78.1%) males and 363 (21.9%) females recorded. The mean age was 30.3 years. The mean follow-up time was 43.9 months when reported (range 16-55 months). Eleven studies utilized the semitendinosus tendon alone, while 21 studies used both semitendinosus and gracilis tendons. There were 82 (3.8%) two-strand grafts, 158 (7.4%) three-strand grafts, 1044 (48.8%) four-strand grafts, 546 (25.5%) five-strand grafts, and 308 (14.4%) six-strand grafts included. Overall, 372 (19.7%) participants had a single-tendon ACLR compared to 1509 (80.2%) participants who had a two-tendon ACLR. The mean graft diameter was 9.4mm when reported. The minimum semitendinosus and gracilis tendon lengths necessary ranged from 210-280mm and 160-280mm respectively. The minimum graft length necessary ranged from 63-120mm except for an all-epiphyseal graft in the paediatric population that required a minimum length of 50mm. The minimum femoral, tibial, and intra-articular graft length ranged from 15-25mm, 15-35mm and 20-30mm respectively. Thirteen studies detailed intra-operative strategies to increase graft size such as adding an extra strand or altering the tibial and/or femoral fixation strategies to shorten and widen the graft. Two studies reported ACL reinjury or graft failure rate. One study found no difference in the re-injury rate between four-, five- and six-strand grafts (p = 0.06) and the other found no difference in the failure rate between four- and five- strand grafts (p = 0.55). There was no difference in the post-operative Lysholm score in 3 studies that compared four- and five-strand ACLR. One of the five studies that compared post-operative IKDC scores between graft types found a difference between two- and three- strand grafts, favoring three-strand grafts. There are many single bundle hamstrings autograft preparation techniques for ACLR that have been used successfully with minimal differences in clinical outcomes. There are different configurations that may be utilized interchangeably depending on the number, size and length of tendons harvested to obtain an adequate graft diameter and successful ACLR

Introduction. Anterior cruciate ligament (ACL) injuries represent a significant burden of disease to the orthopaedic surgeon and often necessitate surgical reconstruction in the presence of instability. The hamstring graft has traditionally been used to reconstruct the ACL but the quadriceps tendon (QT) graft has gained popularity due to its relatively low donor site morbidity. Methods. This is a single centre comparative retrospective analysis of prospectively collected data of patients who had an ACL reconstruction (either with single tendon quadrupled hamstring graft or soft tissue quadriceps tendon graft). All surgeries were performed by a single surgeon using the All-inside technique. For this study, there were 20 patients in each group. All patients received the same post-operative rehabilitation protocol and were added to the National Ligament Registry to monitor their patient related outcome scores (PROM). Results. The average age of patients in the QT group was 29 years (16 males, 4 females) and in the hamstring group was 28 years (18 males, 2 females). The most common mechanism of injury in both groups was a contact twisting injury. There were no statistical differences between the two patient groups in regards to PROMS and need for further revision surgery as analysed on the National Ligament Registry. Conclusions. The all soft tissue QT graft seems to be equivocal to quadrupled hamstring graft in terms of patient function and recovery graft characteristics. Further research may be needed to elucidate the long-term results of the all soft tissue QT graft given its recent increase in use

Little guidance exists in the current literature regarding which patient recorded outcome measures (PROMs) are most clinically appropriate following anterior cruciate ligament reconstruction (ACL) surgery, and what results surgeons should expect or accept. Many PROMs have been validated, but their “ideal” results have not been published, limiting a surgeon's ability to compare their patients’ outcomes with those of their colleagues. We undertook a systematic review of PROMs for ACL to look at common usage and outcomes. After appropriate paper selection, we then undertook a pragmatic meta-analysis (i.e., including all papers that fulfilled the selection criteria, regardless of CONSORT status) and calculated weighted mean outcome scores and standard deviations for the most commonly used PROMs. A comprehensive literature search of all English articles of PubMed and other sources including search terms (‘Patient related outcome measure’ or ‘PROM’) AND ‘anterior cruciate ligament’ (limited to abstract/title) yielded 722 articles. Title review narrowed this to 268, and abstracts review to 151, of which 88 were included in our meta-analysis. Weighted mean and standard deviations were calculated for IKDC, KOOS, Lysholm, Teneger and “VAS Pain” PROMs as the most commonly reported. We identified significant, novel findings relating to selected PROMs and (i) demographics including age, gender and body mass index, (ii) surgical factors including bundle count, strand count, and graft type, and (iii) post operative complications. We clarified the most commonly used PROMs for ACL, and their weighted means and standard deviations. This will allow surgeons to compare results with colleagues, ensuring they meet international levels of quality in PROMs. We have also updated which patient and operative factors have an impact on PROMs scoring to allow for population variance

Abstract. Introduction. Elite athletes sustaining a graft re-rupture after ACL reconstruction (ACL-R) undergo revision reconstruction to enable their return to elite sport. The aim of this study was to determine the rate of return to play (RTP) and competition levels at 2 and 5 years post revision ACL-R. Methodology. A consecutive series of revision ACL-R in elite athletes undertaken by the senior author between 2009 and 2019 was retrospectively reviewed. Outcome measures were RTP rates and competition level. Results. Forty-nine athletes underwent revision ACL-R and were included. 87.8% returned to elite sport of which 75.5% were at the same level. At 2 years post-surgery, 79.6% were still playing, 51% at the same level; and at 5 years 44.4% were still playing, 20% at the same level. Athletes with > 50% thickness chondral lesions were less likely to RTP (66.7% vs 94.6%, p = 0.026) and maintain the same competition level (50% vs 83.8%, p = 0.047). Those with medial meniscus pathology were less likely to RTP at the pre-injury level (64.5% vs 94.4%, p = 0.036). Median career length after revision ACL-R was 73 months (95% CI, 43.4 to 102.6), 23 months at the same level (95% CI, 13.6 to 32.4). The probability of still playing at 5 years post-surgery was 55.9% with 22.5% chance of maintaining pre-injury competition level. Conclusion. RTP rates and competition level of elite athletes decreased over time after revision ACL-R. Chondral pathology of > 50% thickness were associated with lower RTP rates and competition levels

Anatomic all-inside ACL reconstruction using TransLateral technique is a relatively new technique that reduces surgical invasion and pain leading to early recovery. We evaluated clinical outcomes of patients undergoing primary anatomic all-inside ACL reconstruction using TransLateral technique. Retrospective case-series evaluating patients undergoing surgery from June 2013 – December 2017. Patients were followed up clinically and using PROMS including EQ-5D, KOOS, IKDC and Tegner scores. Paired two-tailed student t-tests were used to assess clinical significance. 138 patients were included (115 males, 23 females). Mean age was 30 years (range 16.0 – 60.2). Graft choice included isolated semitendinosus (n=115) or both semitendinosus and gracilis (n=26). Mean graft length and diameter were 62.1mm and 8.7mm. Sixteen cases (11.3%) returned to theatre; MUA for arthrofibrosis (n=4), infection (n=2), haemarthrosis (n=1) and metalwork failure (n=1). Incidence of graft re-rupture was 5.7% (n=8); 7 cases were in the mid-bundle femoral tunnel placement. 52.5% (n=74) had complete peri-operative PROMS scores. Mean peri-operative EQ-5D VAS scores were 69.8 and 78.2 (p=0.02). Mean peri-operative KOOS scores for all domains demonstrated significant improvements (p<0.001). Mean peri-operative IKDC scores were 46.1 and 72.5 (p<0.05) and peri-operative Tegner activity scores were 3.3 and 5.3 (p<0.001). Anatomic all-inside ACL reconstruction using TransLateral technique demonstrates favourable clinical and biomechanical advantages including independent anatomic femoral tunnel placement, bone preservation and use of single tendon graft. Patients report significant improvements in pain, functional outcome, quality of life and return to sports. Mid-bundle femoral tunnel placement has been abandoned due to higher failure rate

Septic arthritis following anterior cruciate ligament reconstruction (ACLR) is a rare and serious complication. Previous studies have shown that septic arthritis is associated with inferior outcome of ACLR. Despite that, there is no standardized treatment protocol, and the course of the disease has mainly been studied within single institutions with a small number of patients. The aim of the present study is to describe the course of septic arthritis following ACLR in a large nationwide cohort. The hypothesis was that the clinical presentation of septic arthritis following ACLR varies according to the infectious agent. The present cohort represents patients with septic arthritis identified in a previous study that analyzed compensation claims reported to the Swedish national insurance company (Löf) in 2005–2014 (1). The diagnosis was confirmed by medical experts at Löf after review of medical records. We conducted a comprehensive analysis of the medical records as well as data available from the Swedish National Knee Ligament Registry (SNKLR) for the study group. The study involved 158 patients who received compensation due to developing septic arhtirits. 94 (59.9%) patients were infected with Coagulase negative staphylococci (CoNS), and 25 patients by Staphyolococcus Aureus (S.Aureus) (15.9%). There was a significant difference between the groups regarding Maximum CRP (p<0.001), and duration between ACLR and first washout operation (p<0.005). S.aureus group had the higest maximum CRP (281) and the shortest duration between ACLR and first washout operation (12 days). The Clinical presentation of septic arthritis following ACLR can vary according to the agent causing the infection, and low virulent agents are responsible for the majority of the infections. Clinicians need to be aware of these differences and consider them when making diagnosis or treatment decisions

Hamstring grafts have been associated with reduced strength, donor site pain and muscle strains following Anterior Cruciate Ligament Reconstruction (ACLR). Traditional graft fixation methods required both semitendinosus and gracilis tendons to achieve a graft of sufficient length and diameter, but newer techniques allow for shorter, broad single tendon grafts. This study seeks to compare the outcomes between Single Tendon (ST) and Dual Tendon (DT) ACLR, given there is no prospective randomised controlled trial (RCT) in the literature comparing outcomes between these options. In this ongoing RCT: (ANZ Clinical Trials Registry ACTRN126200000927921) patients were recruited and randomised into either ST or DT groups. All anaesthetic and surgical techniques were uniform aside from graft technique and tibial fixation. 13 patients were excluded at surgery as their ST graft did not achieve a minimum 8mm diameter. 70 patients (34 ST, 36DT) have been assessed at 6 months, using PROMS including IKDC2000, Lysholm and Modified Cincinnati Knee, visual analog scale for pain frequency (VAS-F) and severity (VAS-S), dedicated donor site morbidity score, KT-1000 assessment, and isokinetic strength. Graft diameters were significantly lesser in the ST group compared to the DT group (8.44mm/9.11mm mean difference [MD],-0.67mm; P<0.001). There was a significant and moderate effect in lower donor site morbidity in the ST group compared to the DT group (effect size [ES], 0.649; P = .01). No differences between groups were observed for knee laxity in the ACLR limb (P=0.362) or any of the patient-reported outcome measures (P>0.05). Between-group differences were observed for hamstrings strength LSI favouring the ST group, though these were small-to-moderate and non-significant (ES, 0.351; P = .147). ST (versus DT) harvest results in significantly less donor site morbidity and this is the first prospective RCT to determine this. There were no differences between ST and DT hamstring ACLR were observed in PROMs, knee laxity and hamstring strength. Younger female patients tend to have inadequate single tendon size to produce a graft of sufficient diameter, and alternative techniques should be considered. Further endpoints include radiological analysis, longer term donor site morbidity, revision rates and return to sport and will continue to be presented in the future

An ACL reconstruction is designed to restore the normal knee function and prevent the onset and progression of degenerative changes such as osteoarthritis. However, contemporary literature provides limited consensus on whether knee degeneration can be attenuated by the reconstruction procedure. The aim of this pilot study was to identify the presence of early osteoarthritis after ACL reconstruction using MRI analysis. 19 patients who had undergone an ACL reconstruction (9 isolated ACL rupture, 8 ACL rupture and meniscectomy, 2 ACL rupture and meniscal repair) volunteered for this study. MRI's were collected preoperatively and postoperatively for analysis with a mean follow up of 23 months. The Boston-Leeds Osteoarthritis Knee Score (BLOKS) was used for the analysis of the articular cartilage by a consultant orthopaedic surgeon. Scores ranged from 0–3, with 0 being total coverage and thickness of the cartilage and 3 being no coverage. Qualitative analysis was then conducted on each patient to determine if the articular cartilage improved, degenerated, or did not change between preoperative and follow-up scans. All patients with isolated ACL rupture were found to either have no change or improved articular cartilage scores in their follow up scans compared preoperatively. In contrast, patients with a meniscal repair displayed worse cartilage scores postoperatively. Lastly, of the patients who had an associated meniscectomy, 6 had worse follow-up results, with the remaining patients showing no change or improved cartilage scores. The present results indicate that patients with an isolated ACL rupture have a reduced risk of developing OA compared to those with associated meniscal injuries. This has implications for analysing the outcome of current ACL reconstruction techniques and in predicting the likelihood of patients developing OA after ACL reconstruction. Future work will involve confirming this pattern in a larger patient sample, as well as exploring additional factors such as time to surgery delay and rehabilitation strategy

Aims. Graft infection following anterior cruciate ligament reconstruction (ACLR) may lead to septic arthritis requiring multiple irrigation and debridement procedures, staged revision operations, and prolonged courses of antibiotics. To our knowledge, there are no previous studies reporting on how gentamicin pre-soaking of hamstring grafts influences infection rates following ACLR. We set out to examine this in our study accordingly. Methods. This retrospective study included 2,000 patients (1,156 males and 844 females) who underwent primary ACLR with hamstring autografts between 2007 to 2017. This included 1,063 patients who received pre-soaked saline hamstring grafts for ACLR followed by 937 patients who received pre-soaked gentamicin hamstring grafts for ACLR. All operative procedures were completed by a single surgeon using a standardized surgical technique. Medical notes were reviewed and data relating to the following outcomes recorded: postoperative infection, clinical progress, causative organisms, management received, and outcomes. Results. Superficial wound infection developed in 14 patients (1.31 %) receiving pre-saline soaked hamstring grafts compared to 13 patients (1.38 %) receiving pre-gentamicin soaked hamstring grafts, and this finding was not statistically significant (p = 0.692). All superficial wound infections were treated with oral antibiotics with no further complications. There were no recorded cases of septic arthritis in patients receiving pre-gentamicin soaked grafts compared to nine patients (0.85%) receiving pre-saline soaked grafts, which was statistically significant (p = 0.004). Conclusion. Pre-soaking hamstring autographs in gentamicin does not affect superficial infection rates but does reduce deep intra-articular infection rates compared to pre-soaking hamstring grafts in saline alone. These findings suggest that pre-soaking hamstring autografts in gentamicin provides an effective surgical technique for reducing intra-articular infection rates following ACLR. Cite this article: Bone Jt Open 2021;2(1):66–71

Aims. Options for the treatment of intra-articular ligament injuries are limited, and insufficient ligament reconstruction can cause painful joint instability, loss of function, and progressive development of degenerative arthritis. This study aimed to assess the capability of a biologically enhanced matrix material for ligament reconstruction to withstand tensile forces within the joint and enhance ligament regeneration needed to regain joint function. Materials and Methods. A total of 18 New Zealand rabbits underwent bilateral anterior cruciate ligament reconstruction by autograft, FiberTape, or FiberTape-augmented autograft. Primary outcomes were biomechanical assessment (n = 17), microCT (µCT) assessment (n = 12), histological evaluation (n = 12), and quantitative polymerase chain reaction (qPCR) analysis (n = 6). Results. At eight weeks, FiberTape alone or FiberTape-augmented autograft demonstrated increased biomechanical stability compared with autograft regarding ultimate load to failure (p = 0.035), elongation (p = 0.006), and energy absorption (p = 0.022). FiberTape-grafted samples also demonstrated increased bone mineral density in the bone tunnel (p = 0.039). Histological evaluation showed integration of all grafts in the bone tunnels by new bone formation, and limited signs of inflammation overall. A lack of prolonged inflammation in all samples was confirmed by quantification of inflammation biomarkers. However, no regeneration of ligament-like tissue was observed along the suture tape materials. Except for one autograft failure, no adverse events were detected. Conclusion. Our results indicate that FiberTape increases the biomechanical performance of intra-articular ligament reconstructions in a verified rabbit model at eight weeks. Within this period, FiberTape did not adversely affect bone tunnel healing or invoke a prolonged elevation in inflammation. Cite this article: Bone Joint J 2019;101-B:1238–1247

Objectives. This study investigated the biomechanical performance of decellularized porcine superflexor tendon (pSFT) grafts of varying diameters when utilized in conjunction with contemporary ACL graft fixation systems. This aimed to produce a range of ‘off-the-shelf’ products with predictable mechanical performance, depending on the individual requirements of the patient. Methods. Decellularized pSFTs were prepared to create double-bundle grafts of 7 mm, 8 mm, and 9 mm diameter. Femoral and tibial fixation systems were simulated utilizing Arthrex suspension devices and interference screws in bovine bone, respectively. Dynamic stiffness and creep were measured, followed by ramp to failure from which linear stiffness and load at failure were measured. The mechanisms of failure were also recorded. Results. Dynamic stiffness was found to increase with greater graft diameter, with significant differences between all groups. Conversely, dynamic creep reduced with increasing graft diameter with significant differences between the 7 mm and 9 mm groups and the 8 mm and 9 mm groups. Significant differences were also found between the 7 mm, 8 mm, and 9 mm groups for linear stiffness, but no significant differences were found between groups for load at failure. The distribution of failure mechanisms was found to change with graft diameter. Conclusion. This study showed that decellularized pSFTs demonstrate comparable biomechanical properties to other ACL graft options and are a potentially viable option for ACL reconstruction. Although grafts can be stratified by their diameter to provide varying biomechanical properties, it may be more appropriate to alter the fixation technique to stratify for a greater diversity of biomechanical requirements. Cite this article: Bone Joint Res 2019;8:518–525

Anterior cruciate ligament (ACL) injuries are one of the most common ligament injury occurring in young and active individuals. Reconstruction of the torn ligament is the current standard of care. Of the many factors which determine the surgical outcome, fixation of the graft in the bony tunnels has significant role. This study compared the clinical and functional outcome in patients who underwent ACL reconstruction by standard anteromedial portal technique with single bundle hamstring graft anchored in the femoral tunnel using rigidfix and cortical button with adjustable loops. The tibial fixation and rehabilitation protocol were same in both groups. 107 patients underwent ACL reconstruction over a two-year period (87 males, 20 females, 44 after motor vehicle accident, 34 after sports injuries, 79 isolated ACL tear, 21 associated medial meniscus tear, 16 lateral meniscus tear and 11 both menisci). Rigid fix group had 47 patients and adjustable loop 60 patients. Clinical evaluation at end of one year showed better stability in rigid fix group regarding Lachman, anterior drawer, pivot shift tests, KT 1000 arthrometer side to side difference and hop limb symmetry index. However, the differences were not statistically significant. Functional evaluation using IKDC 2000 subjective score and Lysholm score showed better results in rigidfix group than variable loop, but was not statistically significant. However, lower scores were noted in patients with concomitant meniscal injury than in isolated acl tear patients and this was statistically significant in both groups. Rigidfix seems to give better graft fixation on femoral side than variable loop, but by the end of one year the functional outcome is comparable in isolated acl reconstructions

The use of platelet-rich plasma (PRP) as an adjuvant to tissue repair is gaining favour in orthopaedic surgery. Tunnel widening after anterior cruciate ligament (ACL) reconstruction is a recognised phenomenon that could compromise revision surgery. The purpose of this study was to determine whether PRP might prevent tunnel widening in ACL reconstruction. Patients undergoing ACL reconstruction using a hamstring graft were randomly allocated either to have PRP introduced into the tunnels peri-operatively or not. CT scanning of the knees was carried out on the day after surgery and at three months post-operatively and the width of the tunnels was measured. Patients were also evaluated clinically at three months, when laxity was also measured. Each group comprised 25 patients, and at three months post-operatively all were pain-free with stable knees, a negative Lachman test and a good range of movement. Arthrometric results had improved significantly in both groups (p < 0.001). Despite slightly less tunnel widening in the PRP group, there was no significant difference between the groups at the femoral opening or the mid-tunnel (p = 0.370 and p = 0.363, respectively) nor at the tibial opening or mid-tunnel (p = 0.333 and p = 0.177, respectively). We conclude that PRP has no significant effect in preventing tunnel widening after ACL reconstruction. Cite this article: Bone Joint J 2013;95-B:65–9

Abstract. Objectives. Identifying risk factors for inferior outcomes after anterior cruciate ligament reconstruction (ACLR) is important for prognosis and patient information. This study aimed to ascertain if BMI, pre-operative scores, demographic data and concomitant injuries in patients undergoing ACLR affected patient-reported functional outcomes. Methods. A prospective review collected data from a single surgeon series of 278 patients who underwent arthroscopic ACLR. BMI, age, gender, graft choice, pre-op Lysholm score, meniscal and chondral injuries were recorded. The Lysholm score, hop test and KT1000 were used to measure post-op functional outcome at one year. Multiple regression analysis was used to determine factors that predicted Lysholm scores at one year. Results. The mean age was 29 years, with 58 female and 220 male patients. The mean pre-op Lysholm score was 53.8. One hunded and seventy-nine patients had meniscal injuries, of which 81 were medial, 60 lateral, and 38 bilateral. Eighteen patients also had chondral injury and 106 patients had no other associated injury. Age, gender, graft type and presence of meniscal or chondral injuries did not affect one-year post-operative Lysholm scores. A BMI greater than 30, physio compliance and preoperative Lysholm scores helped predict one-year post-operative Lysholm scores (p=0.02). Pearson's correlation found a direct link between BMI and post-operative Lysholm (p=0.03). Conclusions. BMI, physio compliance and pre-operative Lysholm scores are the most significant determinants of short-term functional outcome after ACLR. However, the effects of associated injuries may be apparent in the long-term as degenerative changes set in or the continued detriment resulting from the concomitant injury affect outcome. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Purpose: Females are at greater risk for anterior cruciate ligament (ACL) injury than males. Soccer may be a significant risk factor for ACL injury in adolescent females. ACL injury has significant consequences, including early onset of osteoarthritis. The purpose of the study was to determine. the number of ACL reconstruction surgeries performed on females between the ages of 13–18 inclusive in the Capital Health (CH) region from December 2000 to November 2005, and. those due to soccer injuries. Secondly, we describe factors relating to the mechanism of injury. Method: Utilizing regional administrative data, we performed a standardized chart review and telephone interviews with female adolescents who underwent ACL reconstruction in the aforementioned time period. Information gathered included:. Age at reconstruction procedure. Indoor versus outdoor soccer playing surface. Level of play and frequency of participation. The Alberta Soccer Association provided the number of registrants in indoor and outdoor seasons over the same time period. Results: 2,824 ACL reconstruction operations were performed between December 2000 and November 2005. Reconstructions in females took place at an earlier age than in males. There were 266 ACL reconstructions in 256 adolescent females, of which 253 charts were available for review. One hundred and eleven (44%) knees were injured during soccer play. Seven patients with eight ACL reconstructions who injured their ACL playing soccer could not be located. ACL injuries occurred during indoor soccer in 52 (51%) cases despite higher registration in outdoor soccer during the same time-frame. 77 (74%) subjects played competitively and 81 (79%) subjects played two or more times/week. Conclusion: Approximately 10% of ACL reconstructions were performed on adolescent females. Nearly 50% of ACL injuries occurred during soccer play, with a similar number seen in indoor versus outdoor play. Study limitations include the use of administrative data to assess the number of ACL reconstructions rather than ACL injuries. An awareness of the propensity of knee injuries in female soccer players is important. With the increased participation of young females in soccer and the serious lifelong implications of ACL rupture, prevention and training should be improved to lower the incidence of injury

Abstract. Introduction. MRI has been increasingly used as an outcome measure and proxy for healing and integration after ACL reconstruction (ACLR). Despite this, it has not yet been established what a steady state graft MRI appearance is. Methodology. MRI and clinical outcome measures were prospectively taken at 1 and minimum 2 years after hamstring autograft ACLR. MRI graft signal was measured using novel reconstructions both parallel and perpendicular to the graft, with lower signal indicative of better healing and expressed as the signal intensity ratio (SIR), and tunnel apertures analysed. Results. Forty-two patients were included. A proximal graft SIR of 1.9 at 1 year gave a sensitivity of 96% to remain unchanged. High SIR at 1 year, saw a significant reduction after 2 years (p=0.026), also correlated with a significant reduction in aperture area (tibial -6.9mm2, p< 0.001, femoral -13.5mm2, p< 0.001). Mean Tegner activity score was 6 [5-10] with a third of patients scoring either a 9 or 10. Overall, PROMs and knee laxity was not affected by MRI appearance. Conclusion. A proximal graft SIR under 2 at 1 year is a sensitive indicator for a stable graft signal, implying healing. For those that do have high signal at 1 year, a significant reduction is seen in the second year, indicative of ongoing healing. A reduction in tunnel aperture area correlates with a reduction in graft SIR suggesting this could also be a useful measure of graft integration

Evaluate precisely and reproducibly tridimensional positioning of bone tunnels in anterior cruciate ligament reconstructions (ACL). To propose biplanar stereoradiographic imaging as a new reference in tridimensional evaluation of ACL reconstruction (ACLR). Comparing knee 3D models issued from EOStm low-irradiation biplanar X-Ray with those issued from computed tomography (CT-Scan) high definition images will allow a bone morphological description of a previously unseen precision. We carried out the transfer of 3D models from EOStm X-Ray images obtained from 10 patients in the same reference frame with models issued from CT-Scan. Two evaluators reconstructed both pre-operative and post-operative knees, using two different stereoradiographic projections, for a total of 144 knee 3D models from EOStm. A surface analysis by distance mapping allowed us to know the differences or errors between the homologous points of the EOStm and CT reconstructions, the latter being our “bronze-standard”. At the femur, we obtained a mean (95% confidence level) error of 1.5 mm (1.3–1.6) between the EOStm models compared to the Arthro-CT segmentations when using AP-LAT incidences, compared to 1 mm (1.0 – 1.1) with oblique projections. For the tunnels placement analysis, the total radius difference between EOStm and Arthro-CT's femoral tunnel apertures was 0.8 mm (0.4–1.2) in AP-LAT and 0.6 mm (0.0–1.2) in oblique views. These femoral apertures positioning on EOStm models were within 4.3 mm (3.0–5.7) of their homologues on CT-Scan models, 4.6 mm (3.5–5.6) with the oblique views. Furthermore, 9.3o (7.2–11.4) of difference in direction between femoral tunnels from EOStm models and CT reconstructions is obtained with AP-LAT projections, 8.3o (6.6–10) with obliques views. Measures of these parameters were also performed at the tibia. According to the intra and inter-reproducibility analysis of our knee 3D models, EOStm biplanar X-Ray images prove to be fast, efficient and precise in the design of ACLR 3D models with respect to CT-Scan. Our results also propose the recourse of oblique stereoradiographic projections for the realization of knee 3D models. These models will be subjects of further analysis and will allow us eventually to propose a new frame of reference guiding the positioning of the tunnels in the ACLR

The purpose of this study was to investigate the safety and outcome of bilateral simultaneous ACL reconstruction. In patients presenting with an ACL-deficient knee, 2 – 4% have bilateral ACL deficiency. A staged or simultaneous approach can be adopted when the patient requires reconstructive surgery for both knees. We report a case series of 8 patients (6 male, 2 female, average age 30.4 years) who underwent bilateral simultaneous ACL reconstruction. Simultaneous or bilateral ACL reconstruction using ipsilateral patella tendon graft has been reported as a safe procedure with outcome and complication rate no different to unilateral procedures. Considerable cost savings of simultaneous over staged procedures have also been described. There are no case series in the published literature that describe the use of hamstring tendon autograft for bilateral simultaneous ACL reconstruction. We used two camera stack systems and instrument sets to allow for simultaneous bilateral surgery by two surgical teams. Quadrupled hamstring tendon graft was used in 4 patients although in one patient patella tendon graft was used on the second side due to poor quality of hamstring tendons. Patella tendon graft was also used in a further 4 patients. At two weeks all patients were able to discard crutches and were independent in mobility. There was no difference in outcome at one year between those patients undergoing bilateral simultaneous ACL reconstruction in comparison to the outcomes of unilateral ACL reconstruction with respect to Lysholm, Tegner and IKDC scores. The mean follow up period was 2.3 years. Our results demonstrate that bilateral simultaneous ACL reconstruction is safe and cost effective. A simultaneous approach also has the benefit of reducing the overall period of rehabilitation required by the patient. We report good short-term functional outcome but no long-term data is yet available

Introduction. Unicompartmental knee arthroplasty (UKA) currently experiences increased popularity. It is usually assumed that UKA shows kinematic features closer to the natural knee than total knee arthroplasty (TKA). Especially in younger patients more natural knee function and faster recovery have helped to increase the popularity of UKA. Another leading reason for the popularity of UKA is the ability to preserve the remaining healthy tissues in the knee, which is not always possible in TKA. Many biomechanical questions remain, however, with respect to this type of replacement. 25% of knees with medial compartment osteoarthritis also have a deficient anterior cruciate ligament [1]. In current clinical practice, medial UKA would be contraindicated in these patients. Our hypothesis is that kinematics after UKA in combination with ACL reconstruction should allow to restore joint function close to the native knee joint. This is clinically relevant, because functional benefits for medial UKA should especially be attractive to the young and active patient. Materials and Methods. Six fresh frozen full leg cadaver specimens were prepared to be mounted in a kinematic rig (Figure 1) with six degrees of freedom for the knee joint. Three motion patterns were applied: passive flexion-extension, open chain extension, and squatting. These motion patterns were performed in four situations for each specimen: with the native knee; after implantation of a medial UKA (Figure 2); next after cutting the ACL and finally after reconstruction of the ACL. During the loaded motions, quadriceps and hamstrings muscle forces were applied. Infrared cameras continuously recorded the trajectories of marker frames rigidly attached to femur, tibia and patella. Prior computer tomography allowed identification of coordinate frames of the bones and calculations of anatomical rotations and translations. Strains in the collateral ligaments were calculated from insertion site distances. Results. Knee kinematics and collateral ligament strains were quite close to the native situation after both UKA and ACL reconstruction for all motor tasks. Nevertheless, some statistically significant differences were detected, which may be relevant clinically and biomechanically. In general, insertion of a UKA led to a knee joint which was somewhat less adducted (Figure 3), with a medial femoral condyle located slightly higher, confirming previously published findings [2]. These effects were slightly reduced both after cutting as well as after reconstructing the ACL. The joint became somewhat less stable in the AP direction after insertion of a UKA and this instability persisted not only after cutting but even after reconstructing the ACL

Aims. To investigate the risk factors for progression of articular cartilage damage after anatomical anterior cruciate ligament (ACL) reconstruction. Patients and Methods. A total of 174 patients who underwent second-look arthroscopic evaluation after anatomical ACL reconstruction were enrolled in this study. The graded condition of the articular cartilage at the time of ACL reconstruction was compared with that at second-look arthroscopy. Age, gender, body mass index (BMI), ACL reconstruction technique, meniscal conditions, and other variables were assessed by regression analysis as risk factors for progression of damage to the articular cartilage. Results. In the medial compartment, multivariable logistic regression analysis indicated that partial medial meniscectomy (odds ratio (OR) 6.82, 95% confidence interval (CI) 2.11 to 22.04, p = 0.001), pivot-shift test grade at the final follow-up (OR 3.53, CI 1.39 to 8.96, p = 0.008), BMI (OR 1.15, CI 1.03 to 1.28, p = 0.015) and medial meniscal repair (OR 3.19, CI 1.24 to 8.21, p = 0.016) were significant risk factors for progression of cartilage damage. In the lateral compartment, partial lateral meniscectomy (OR 10.94, CI 4.14 to 28.92, p < 0.001) and side-to-side differences in anterior knee laxity at follow-up (OR 0.63, p = 0.001) were significant risk factors. Conclusion. Partial meniscectomy was found to be strongly associated with the progression of articular cartilage damage despite r anatomical ACL reconstruction. Cite this article: Bone Joint J 2018;100-B:285–93

Introduction. It is widely accepted that intra-articular graft reconstruction with correct placement stands the greatest chance of abolishing symptomatic instability secondary to anterior cruciate ligament (ACL) deficiency. It is estimated that at least 100,000 ACL reconstructions are performed a year in the USA, where approximately 30% of the population are currently clinically obese. In the UK obesity is a growing problem and as participation in exercise is seen as an important part of the strategy in improving the health of the nation, it is likely that there will be an increasing number of ligament injured patients from this sub group. Does obesity prejudice outcome? There is very little published work on this association of obesity and ligament reconstruction. It has been reported that subjects with a BMI greater than 30 have 0.35 times the odds of success as subjects with a normal BMI. Methods. We know the strains placed across the ACL in activities of daily living and the fixation strengths of most of the commonly used ACL reconstruction methods. Using mathematical modeling we can predict likely limits in patient BMI for the materials and rehabilitation regimens in common practice. The theoretical point where BMI is likely to prejudice outcome and cause early graft failure can be calculated. This has implications for patient selection, producing a procedure of limited clinical value. Mathematical modelling can also show the potential problems with weight gain in patient groups after successful ACL reconstruction. Can ACL reconstruction be justified in the obese?

The aim of this study was to determine current practice in anterior cruciate ligament reconstruction amongst BASK members. This was an internet-based survey where members were invited to complete a questionnaire on ACL reconstruction. Of the 365 BASK surgeons performing ACL reconstruction, 241 completed the questionnaire (response rate 66%). 147(61%) of surgeons used both hamstring and patellar tendon grafts, 71(29%) used only hamstrings and 21(9%) used patellar tendon only. All surgeons used ipsilateral autograft. 157 (65%) used the transtibial technique for femoral tunnel placement with 80(33%) using the anteromedial portal technique. Of those using the anteromedial portal, the most common femoral fixation devices were the Endobutton (34%) and RCI screw (34%). Interference screw fixation (81%) was the most common tibial fixation in the same group of surgeons with the RCI screw being the most common (63%). 19% (45/241) of surgeons were performing double bundle ACL reconstructions in select cases. Hamstring femoral fixation was with a suspension device in 79% and interference screw in 18%. Of those using a suspension device the Endobutton was most common (48%) followed by Transfix (26%) and Rigidfix (19%). Tibial fixation was most commonly achieved by interference screw (57%) followed by Intrafix (30%). With patellar tendon graft the most popular femoral fixation was with an interference screw (66%) followed by suspension (34%). All surgeons used interference screw for tibial fixation. 90% of surgeons (217) allow immediate full weight-bearing as tolerated irrespective of fixation type with 8% delaying full weight bearing between 1 and 3 weeks. The results show the wide spread of variation in practice of ACL reconstruction. With recent renewed interest in a more anatomic placement of tunnels, the use of the anteromedial portal may continue to increase. With such a wide variation in techniques, grafts and fixation implants used, a register may help assess outcomes

The primary purpose of this study was to assess whether patients presenting with clinical graft laxity following primary anatomic anterior cruciate ligament (ACL) reconstruction using hamstring autograft reported a significant difference in disease-specific quality-of-life (QOL) as measured by the ACL-QOL questionnaire. Clinical ACL graft laxity was assessed in a cohort of 1134/1436 (79%) of eligible patients using the Lachman and Pivot-shift tests pre-operatively and at 12- and 24-months following ACL reconstruction. Post-operative ACL laxity was assessed by an orthopaedic surgeon and a physical therapist who were blinded to each other's examination. If there was a discrepancy between the clinical examination findings from these two assessors, then a third impartial examiner assessed the patient to ensure a grading consensus was reached. Patients completed the ACL-QOL questionnaire pre-operatively, and 12- and 24-months post-operatively. Descriptive statistics were used to assess patient demographics, rate of post-operative ACL graft laxity, surgical failures, and ACL-QOL scores. A Spearman rho correlation coefficient was utilised to assess the relationships between ACL-QOL scores and the Lachman and Pivot-shift tests at 24-months post-operative. An independent t-test was used to determine if there were differences in the ACL-QOL scores of subjects who sustained a graft failure compared to the intact graft group. ACL-QOL scores and post-operative laxity were assessed using a one-way analysis of variance (ANOVA). There were 70 graft failures (6.17%) in the 1134 patients assessed at 24-months. A total of 226 patients (19.9%) demonstrated 24-months post-operative ACL graft laxity. An isolated positive Lachman test was assessed in 146 patients (12.9%), an isolated positive Pivot-shift test was apparent in 14 patients (1.2%), and combined positive Lachman and Pivot-shift tests were assessed in 66 patients (5.8%) at 24-months post-operative. There was a statistically significant relationship between 24-month post-operative graft laxity and ACL-QOL scores (p < 0.001). Specifically, there was a significant correlation between the ACL-QOL and the Lachman test (rho = −0.20, p < 0.001) as well as the Pivot-shift test (rho = −0.22, p < 0.001). There was no significant difference between the scores collected from the graft failure group prior to failure occurring (mean = 74.38, SD = 18.61), and the intact graft group (mean = 73.97, SD = 21.51). At 24-months post-operative, the one-way ANOVA demonstrated a statistically significant difference between the ACL-QOL scores of the no laxity group (mean = 79.1, SD = 16.9) and the combined positive Lachman and Pivot-shift group (mean = 68.5, SD = 22.9), (p = 0, mean difference = 10.6). Two-years post ACL reconstruction, 19.9% of patients presented with clinical graft laxity. Post-operative graft laxity was significantly correlated with lower ACL-QOL scores. The difference in ACL-QOL scores for patients with an isolated positive Lachman or Pivot-shift test did not meet the threshold of a clinically meaningful difference. Patients with clinical laxity on both the Lachman and Pivot-shift tests demonstrated the lowest patient-reported ACL-QOL scores, and these results exceeded the minimal clinically important difference

Thirty- seven patients were enrolled in a single-blind prospective randomized clinical trial comparing the use of the Endopearl in femoral fixation in otherwise similar anterior cruciate ligament (ACL) reconstructions. Evaluation pre-operatively, three months, six months and eighteen months post-operatively suggested significant difference in the side to side KT-1000 values suggesting improved graft fixation with the EndoPearl by eighteen months post surgery with no differences in the Mohtadi ACL QOL questionnaire. Thus, when bioabsorbable interference screws are used for ACL reconstruction, the use of the EndoPearl improves anterior-posterior stability up to eighteen months post-operatively. The EndoPearl is an adjunct to bioabsorbable interference screw fixation in the femoral tunnel in ACL reconstruction. The purpose of the study was to assess the clinical effectiveness of the EndoPearl using the KT-1000 Knee Arthrometer and the Mohtadi ACL Quality of Life (ACL-QOL) Questionnaire. The application of the EndoPearl in hamstring ACL reconstruction has no significant benefit when compared to conventional treatment in KT-1000 and ACL-QOL Questionnaire outcomes. Prospective Single-blind Randomized Clinical Trial. ACL reconstruction with autogenous semitendino-sus and gracilis tendons was performed on thirty-seven patients. Pre-operatively, three months, six months and a eighteen months post-operatively, patients’ knees were evaluated using the KT-1000 Knee Arthrometer and the ACL-QOL questionnaire. Statistically significant differences were achieved in terms of KT-1000 side-to-side differences between the study group and the control group at six months and eighteen months post-operatively; the mean-side-to-side differences are significantly less in the study group when compared to the control group. Statistically significant differences could not be detected when comparing the ACL-QOL questionnaire between the two groups. The application of the EndoPearl in conjunction with a bioscrew in the femoral tunnel in autogenous ACL reconstruction using semitendinosus and gracilis tendon grafts provides a significantly decreased laxity up to eighteen months post-operatively in terms of KT-1000 side-to-side differences. In an accelerated post-operative rehabilitation program, patients and doctors have increased confidence in terms of graft stability with the application of the Endo-Pearl in hamstring ACL reconstruction. Please contact author for pictures and/or diagrams

Hop tests are used to determine return to sports after ACL reconstruction. They mostly measure distance and symmetry but do not assess kinematics and kinetics. Recently, biomechanical evaluations have been incorporated into these functional jump tests for the better assessment of return to sport. We assessed the sagittal plane range of motion (ROM) of the knee, the deviation axis of rotation (DAOR), and the vertical ground reaction force (vGRF) normalized to body weight in nine healthy participants during the single leg (SLH) and crossover hop tests (COHT). Participants' leg lengths were measured. Jumping distances were marked in the test area as being 4/5 of the leg length. Four sensors were placed on the thighs, the legs and the feet. These body parts were handled as a single rigid body. Eight 480 Hz cameras were used to capture the movements of these rigid bodies. vGRF at landing were measured using a force plate (Bertec, Inc, USA). The ROM of the knee joint and the DAOR were obtained from kinematic data. Participants' joint kinematics metrics were similar in within-subjects statistical tests for SLH and COHT. We therefore asked whether the repeated vGRF normalized to body weight will be similar in both legs during these jumps. Joint kinematics metrics however were different in between subjects indicating the existence of a personalized jumping strategy. These hop tests can be recorded at the beginning of the training season for each individual, which can establish a comparative evaluation database for prospective lower extremity injury recovery and return to sport after ACL injury

Introduction: Some authors have suggested that the results of ACL reconstruction in females using hamstring tendon (HS) autograft are inferior to those using patellar tendon (PT) autograft. The purpose of this study was to compare our results of ACL reconstruction in females using both graft types. Material and methods: 80 females who had undergone primary ACL reconstruction using either HS (n=48) or PT (n=32) were evaluated at mean 3.7 year follow-up (2.4 – 5.7). The same surgeon carried out all the reconstructions, using Endobutton femoral fixation and interference screw tibial fixation, and the same rapid rehabilitation protocol was followed by all patients. Independent assessment included IKDC 2000, SF-36, and Cincinnati Sports Activity Score (CSAS) and measurements of anterior knee pain (AKP), kneeling pain and anterior knee laxity (KT-1000). Results: One patient in the PT group sustained a traumatic graft rupture. For the remaining patients there were no significant differences between the two graft types in terms of objective IKDC 2000 or KT-1000. In terms of subjective IKDC the HS group scored significantly higher (PT: 85 pts., HS: 90pts, p< 0.05), as well as for the CSAS (PT:72.8 vs. HS: 82.1, p< 0.01) and for the SF-36 on the Physical Functioning (PT:90 vs. HS:95, p< 0.01) and General Health subscales (PT:79 vs. HS 86, p< 0.05). Although there was no significant difference in AKP between the two groups, there was a significantly greater mean kneeling pain in the PT group (PT:4.1 vs. HS: 2.5, p=0.001). Conclusions: Both PT and HS primary ACL reconstructions appear to provide comparable good objective results in females, but ACL reconstruction with HS showed significantly better subjective results. This finding seems to be related to less donor site problems compared with PT. Our results indicate that a quadruple hamstring autograft is an adequate alternative to a patellar tendon autograft for ACL reconstruction in female patients

Anterior cruciate ligament (ACL) reconstruction is the current standard of care for ACL tears. However, the results are not consistently successful, autografts or allografts have certain disadvantages, and synthetic grafts have had poor clinical results. The aim of this study was to determine the efficacy of tissue engineering decellularized tibialis tendons by recellularization and culture in a dynamic tissue bioreactor. To determine if recellularization of decellularized tendons combined with mechanical stimulation in a bioreactor could replicate the mechanical properties of the native ACL and be successfully used for ACL reconstruction in vivo. Porcine tibialis tendons were decellularized and then recellularized with human adult bone marrow-derived stem cells. Tendons were cultured in a tissue bioreactor that provided biaxial cyclic loading for up to 7 days. To reproduce mechanical stresses similar to hose experienced by the ACL within the knee joint, the tendons were subjected to simultaneous tension and torsion in the bioreactor. Expression of tendon-specific genes, and newly synthesized collagen and glycosaminoglycan (GAG) were used to quantify the efficacy of recellularization and dynamic bioreactor culture. The mechanical strength of recellularized constructs was measured after dynamic stimulation. Finally, the tissue-engineered tendons were used to reconstruct the ACL in mini-pigs and mechanical strength was assessed after three months. Dynamic bioreactor culture significantly increased the expression of tendon-specific genes, the quantity of newly synthesized collagen and GAG, and the tensile strength of recellularized tendons. After in vivo reconstruction, the tensile strength of the tissue-engineered tendons increased significantly up to 3 months after surgery and were within 80% of the native strength of the ACL. Our translational study indicates that the recellularization and dynamic mechanical stimuli can significantly enhance matrix synthesis and mechanical strength of decellularized porcine tibialis tendons. This approach to tissue engineering can be very useful for ACL reconstruction and may overcome some of the disadvantages of autografts and allografts

Statement: This is the first report of a supracondylar femoral fracture following ACL reconstruction using a transfixation pin. Methods: A 38 yr old secretary was admitted for an elective ACL reconstruction. The operative procedure involved harvesting of the hamstrings, with drilling of an 8 mm tibial tunnel and the graft fixed with a 10 × 35mm screw. Femoral tunnel placement was performed arthroscopically and fixation of the graft in the tunnel was using the Arthrex system. No untoward events were recorded in the notes. Post-operatively, the patient was mobilised according to the surgeons standard guidelines. At 6 week review, the patient complained of increasing pain, inability to fully weight bear and a decreased range of movement. 35 fixed flexion deformity, 30 degrees external rotation and 20 degrees of valgus of the leg. Radiographs revealed a transverse supracondylar fracture extending through the level of the pin fixation. Subsequent surgery involved an osteotomy to correct the deformity and application of a lateral femoral plate After fixation direct inspection of the retained anterior cruciate ligament, revealed and intact graft that functioned through the full range of movement. At nine months, the patient is fully weight bearing has returned to her pre-injury sporting level and has a range of movement of 0–110 degrees. There was no objective knee instability and the patient is satisfied with the outcome. Femoral fractures have rarely been reported in the literature following ACL reconstruction and these are usually associated with drilling of an enlarged femoral tunnel. We report a rare case of a transverse supracondylar femoral fracture following ACL reconstruction, with the fracture occurring through the fixation tract not the femoral tunnel

Purpose: This study was performed to assess the incidence of generalized ligament laxity in patients undergoing revision ACL reconstruction. Methods and Results: Prospective data was collected for 40 patients undergoing revision ACL reconstruction, between 2004 and 2009 under the care of a single orthopaedic consultant including demographic details, graft used during primary and revision ACL reconstruction and causes of graft failure. Clinical examination was used to assess the ligament laxity using the Beighton score. Laxity is scored on a 0–9 scale. Scores of 4 or above are indicative of generalized ligament laxity. Brighton criteria is used to diagnose Benign Joint Hypermobility Syndrome (BJHS) and use signs and symptoms along with Beighton score. The most common graft used was a quadruple hamstring in 23 patients (57%). The causes of graft failure were trauma in 22 patients (55%), biological in 17 patients (42%) and infection in 1 patient (2.5%). The revision ACL graft was patella tendon in 23 patients (57%), allograft tendon was used in 11 patients (28%) and quadruple hamstring was used in 4 patients (10%). The average Beighton score for these patients was 3 with a range from 0–9. 20 patients (50%) in this group had a Beighton score of 4 or more. Only 6 patients (15%) fulfilled the Brighton criteria for BJHS. Conclusion: We found that there is a high incidence (50%) of generalized ligament laxity in patients undergoing revision ACL reconstruction. Biological failure is common (42%) in these patients after using autogenous tendons. We recommend the use of allograft for primary ACL reconstruction in patients with generalized ligament laxity

Anterior Cruciate Ligament (ACL) rupture is one of the commonest injuries in sports medicine. However, the rates of the reported graft re-rupture range from 2–10%, leading to around 3000 to 10000 revision ACL reconstructions in United States per annum. Inaccurate tunnel positions are considered to be one of the commonest reasons leading to failure and subsequent revision surgery. Additionally, there remains no consensus of the optimal position for ACL reconstructions. The positions of the bone tunnels in patients receiving ACL reconstruction are traditionally assessed using X-rays. It is well known that conventional X-ray is not a precise tool in assessing tunnel positions. Thus, there is a recent trend in using three-dimensional (3D) CT. However, routine CT carries a major disadvantage in terms of significant radiation hazard. In addition, it is both inconvenient and expensive to use CT as a regular assessment tools during the follow-up. The goal of the present work is to develop a novel 2D-3D registration method using single X-ray image and a surface model. By performing such registration for two post-operative X-rays, we can further calculate the 3D tunnel positions after ACL reconstructions. Our framework consists of five parts: (1) a surface model of the knee, (2) a 2D-3D registration algorithm, (3) a 3D tunnel position calculation, (4) a graphic user interface (GUI), and (5) a semi-transparency rendering. Among them, the crucial part is our 2D-3D registration method that estimates the relative position of the knee model in the imaging coordinate system. Once registered, the 3D position of an ACL tunnel in the knee model is calculated from the imaging geometry. The only interaction required is to mark the ACL tunnels on the X-rays through the GUI. We propose two 2D-3D registration methods. One is a contour-based method that uses pure geometric information. Most methods in this category accomplish the registration by extracting contours in X-rays, establishing their correspondences on the 3D model, and calculating the registration parameters. Unlike these methods, which need point-to-point correspondences, our method optimises the registration parameters in a statistical inference framework without giving or establishing point-to-point correspondences. Due to the use of the statistical inference, our method is robust to the spurs and broken contours that automatically extracted by the contour detector. The second method takes into account both the geometric shape of the object and the intensity property (intensity changes) of the image, where the intensity changes can be detected via image gradients. The use of gradient is based on the interpretation that two images are considered similar, if intensity changes occur at the same locations. The angles between the image gradients and the projected surface normals were used as a distance measure. The summation of the measures for all projected model points gives us the gradient term, which we multiply the contour-based measurement. Multiplication is preferred over addition because addition of the terms would require both terms to be normalised. To evaluate the feasibility of our methods, a simulation study was conducted using Digitally Reconstructed Radiographs (DRR) of a sawbone underwent a single-bundle ACL reconstruction performed by an experienced orthopedic surgeon. The real position of the bone tunnel entry point was obtained using the CT images, which were acquired using a custom-made well-calibrated cone-beam CT. The knee model was built by downsampling and smoothing the high-resolution CT reconstructions. It is important in our experiments to make the model different from the original reconstruction since this simulates the condition in which patient's CT is unavailable. Two DRRs generated from approximately anteroposterior and lateral viewpoints were used. For each DRR, 50 trials of 2D-3D registration were carried out for the femoral part using 50 different initialisations, which were randomly selected from the values independently and uniformly distributed within ±10 degrees and ±10 mm of the ground-truth. Compared with the ground-truth established using the CT images, our single image contour-based method achieved accurate estimations in rotations and in-plane translations, which were (−0.67±1.38, −0.98±0.84, −0.42±0.71) degrees and (0.11±0.26, −0.06±1.20) mm for the anteroposterior image, and (−0.78±0.76, −0.37±0.87, 0.70±0.88) degrees and (−0.14±0.22, 0.31±0.71) mm for the lateral one, respectively. The same experiments were also performed using the second method. However, it did not produce desirable results in our experiments. The tunnel entry point was then calculated using the averaged registration result of our contour-based method. The entry point of the tunnel was obtained with high accuracy of 1.25 mm distance error from the real position of the entry point. For the 2D-3D registration, the estimated off-plane translations showed relatively low accuracy. It is well known that the depth can be difficult to be accurately estimated using one single image. As the result showed, the accuracy in rotations and in-plane translations is more important for ACL tunnel position estimation in our framework. As for the image gradient, it is too sensitive to the small perturbation caused by image noises. A more robust way of integrating the gradient information into our contour-based method is required. We propose a novel approach for estimating the 3D position of bone tunnels in ACL reconstruction using two post-operative X-rays. It was tested in a sawbone study using DRRs. The most significant advantage of our approach is to potentially eliminate the necessity of acquiring a patient's CT. The success in developing and validating the proposed workflow will allow convenient and precise assessment of tunnel positions in ACL reconstruction with minimal risk of radiation hazard

No consensus exists regarding the optimal graft choice between allogenic and autologous graft. Incidence of septic arthritis following ACL reconstruction is rare but may dependent on the graft type. Our meta-analysis assesses the difference in incidence of septic arthritis after ACL reconstruction across three groups of grafts: hamstring autografts, bone patellar tendon bone (BPTB) autografts and allografts of any type. A literature search was performed without language restriction on PubMed and EMBASE databases. We identified 245 infected ACL grafts across 15 included studies that provided a breakdown of infection incidence by graft type. A meta-analysis was performed using a random-effects model to estimate the overall infection rates and those for different graft types. Summary risk ratios and 95% confidence intervals (CIs) were calculated and reported for each outcome. Publication bias with respect to infection rates was estimated using a funnel plot. Our meta-analysis shows an overall ACL graft infection rate of 0.6% (CI 0.3% – 1.3%). The incidence was highest in autologous hamstring grafts at 1.1% at (CI 0.8% – 1.6%). That of allografts and autologous BPTB grafts was similar at 0.5% (CI 0.2%–1.0%) and 0.4% (CI 0.2% – 0.7%), respectively. Full breakdown of the meta-analysis results by study and graft type is reported in Figure 1. Septic arthritis after ACL reconstruction remains a rare (<1%) but a serious complication. Allograft rates of infection were not higher than those the autografts, contrary to the theoretical concerns. Therefore a higher infection risk should not be cited as a reason for not using it. The reason for the apparently higher infection rate with hamstring autografts is unclear and requires further research. The results of our meta-analysis may aid informed discussions between surgeons and patients about the risk of infection after ACL reconstructive surgery and graft choice

Summary Statement. ACL reconstruction using a quadriceps tendon autograft was quantitatively evaluated using a robotic testing system. Biomechanical results on joint stability and graft function support its use as an alternative to the hamstrings. Introduction. Recently, a number of surgeons have chosen the quadriceps tendon (QT) autograft as an alternative autograft over the hamstrings tendon for ACL reconstruction because its bone-to-bone healing on one side, large size, and preservation of lateral and rotatory knee function could lead to fewer post-operative complications. However, there have been little or no biomechanical studies that quantitatively evaluate knee function after reconstruction using a QT autograft. Therefore, the objective of this study was to assess the function of a reconstructed knee with a QT autograft and compare the results with a quadrupled semitendinosus and gracilis (QSTG) tendon autograft on the same knee. Methods. Ten human cadaveric knees (57.4 ± 4.2 years of age) were tested using a robotic/UFS testing system in 4 knee states: intact, ACL-deficient, and after ACL reconstruction with both QT and QSTG autografts. Reconstructions were performed in randomised order using posterolateral femoral tunnel placement. The knee kinematics in each state were measured at 5 flexion angles (full extension, 15°, 30°, 60°, and 90°) under 3 externally applied loading conditions: (1) 134 N anterior tibial load (ATL), (2) 134 N ATL with 200 N axial compression, and combined rotatory (CR) load of 10 Nm valgus and 5 Nm internal tibial torque (at 15° and 30°). Based on the established procedure, knee kinematics and in-situ forces were obtained using the principle of superposition. A repeated measures ANOVA was used to compare anterior tibial translation (ATT) and in-situ forces between the knee states at each flexion angle, with a Bonferroni post-hoc analysis. Results. Under the ATL, the ATT was found to be restored to within 1.1 mm of the intact knee for both reconstructions (P > 0.05). The in-situ forces in the grafts were also not significantly different from those in the intact ACL except in deep flexion (P < 0.05 at 90° for both grafts). With added axial compression, both reconstructions could still restore the ATT to within 2.4 mm of the intact joint at all flexion angles, and the in-situ forces in both grafts were within 25 N of the intact ACL at 15°, 30°, and 60° (P > 0.05). Under the CR load, knee kinematics and in-situ forces in the grafts were not significantly different from the intact ACL at any tested angle (P > 0.05). Further, no significant differences could be detected between the reconstructions under any experimental condition (P > 0.05). Discussion/Conclusion. ACL reconstruction with a QT autograft was found to restore knee function close to levels of the intact knee and similar to those reconstructed with a QSTG autograft. These results support clinical findings suggesting the QT autograft as a viable alternative for ACL reconstruction

Objective: The aim of this prospective observational study was to evaluate the feasibility of performing ACL reconstruction with femoral nerve block as a day-case procedure, implement the necessary changes and audit the outcomes following instigation of a day-case protocol. Methods: From November 2005 to April 2006 all patients undergoing ACL reconstruction were entered into a day-case feasibility study. Any issues preventing day-case discharge were identified, and in November 2006 changes were implemented to address these. Since then all ACL reconstruction patients have been treated as day-cases using femoral nerve blocks. Patients are discharged if safe, and contacted 1 and 7 days postoperatively to detect any problems and to assess patient satisfaction. Patients undergoing ACL reconstruction with femoral nerve block in the independent sector, by the same surgeon but without a strict protocol were used as a comparison group. Results: 18 patients have followed the day-case pathway, 15 (83%) being discharged as day-cases. The other cases had afternoon surgery delaying discharge. Only 25% (3/12) patients treated in the independent sector were discharged on the day of surgery. All patients had good working femoral nerve blocks, were able to mobilise safely with crutches and reported no adverse effects from their blocks at follow-up phone calls. All reported good analgesia at home and high satisfaction with being a day-case. Conclusions: With appropriate education of patients and staff, and following a day-case protocol, ACL reconstruction with femoral nerve block is a safe day-case procedure with high patient satisfaction

We examined whether enamel matrix derivative (EMD) could improve healing of the tendon–bone interface following reconstruction of the anterior cruciate ligament (ACL) using a hamstring tendon in a rat model. ACL reconstruction was performed in both knees of 30 Sprague-Dawley rats using the flexor digitorum tendon. The effect of commercially available EMD (EMDOGAIN), a preparation of matrix proteins from developing porcine teeth, was evaluated. In the left knee joint the space around the tendon–bone interface was filled with 40 µl of EMD mixed with propylene glycol alginate (PGA). In the right knee joint PGA alone was used. The ligament reconstructions were evaluated histologically and biomechanically at four, eight and 12 weeks (n = 5 at each time point). At eight weeks, EMD had induced a significant increase in collagen fibres connecting to bone at the tendon–bone interface (p = 0.047), whereas the control group had few fibres and the tendon–bone interface was composed of cellular and vascular fibrous tissues. At both eight and 12 weeks, the mean load to failure in the treated specimens was higher than in the controls (p = 0.009). EMD improved histological tendon–bone healing at eight weeks and biomechanical healing at both eight and 12 weeks. EMD might therefore have a human application to enhance tendon–bone repair in ACL reconstruction

Objective: To compare double bundle ACL reconstruction kinematics to single bundle reconstruction, intact knee and ACL deficient knee employing an electromagnetic device in six cadaver knees under different antero-posterior and rotational loading conditions. Methods: All the tests were performed with an intact ACL, with a deficient ACL and after single and double bundle ACL reconstruction. In double bundle ACL reconstruction two tibial tunnels were drilled: for the anteromedial the 65 degrees Howell guide was employed; the posterolaetral was drilled through a prototype jig attached to the first guide. Two femoral tunnels were drilled outside-in with the Rear Entry guide. A 6 millimetres bovine tendon graft was employed and fixed to bone with interference screws. Results: Posterior drawer loading conditions did not show differences between intact knee, single and double ACL reconstruction independently from rotational stresses. Under an anterior drawer test double bundle ACL reconstruction restored anteroposterior laxity significantly better than single bundle reconstruction at 20 and 40 degrees of flexion. A trend towards a better rotational control of double bundle reconstruction was observed in extension

Aims

Adenosine, lidocaine, and Mg²⁺ (ALM) therapy exerts differential immuno-inflammatory responses in males and females early after anterior cruciate ligament (ACL) reconstruction (ACLR). Our aim was to investigate sex-specific effects of ALM therapy on joint tissue repair and recovery 28 days after surgery.

Aims

The purpose of this study is to determine an individual’s age-specific prevalence of total knee arthroplasty (TKA) after cruciate ligament surgery, and to identify clinical and genetic risk factors associated with undergoing TKA.

Objective: The aim of this prospective observational study was to evaluate the feasibility of performing ACL reconstruction with femoral nerve block as a day-case procedure, implement this change and audit our outcomes. Methods: From November 2005 to April 2006 all patients undergoing ACL reconstruction were entered into a day-case feasibility study. Any issues preventing day-case discharge were identified, and in November 2006 changes were implemented to address these. Since then all ACL reconstruction patients have been treated as day-cases using femoral nerve blocks. Patients are discharged if safe, and contacted 1 and 7 days postoperatively to detect any problems and to assess patient satisfaction. Results: 23 patients have followed the day-case pathway, 15 being discharged as day-cases. The other cases had afternoon surgery delaying discharge or surgery in the independent sector where the protocol was not enforced. All patients had good working femoral nerve blocks, were able to mobilise safely and easily with crutches and reported no adverse effects from their blocks at follow-up phone calls. All reported good analgesia at home and high satisfaction with being a day-case. Conclusions – With appropriate education of patients and staff, ACL reconstruction with femoral nerve block is a safe day-case procedure with high patient satisfaction

Background: Studies have shown that normal tibio-femoral rotational kinematics is not regained following single-bundle ACL reconstruction and that 14–30% of patients may have a residual “pivot glide”. It has been suggested that 2-bundle reconstruction could better control this laxity, but this not been demonstrated conclusively in-vivo. This study tested the hypothesis that 2-bundle ACL reconstruction improves the control of the Pivot Shift. Methods: We measured the mean maximum tibial translation and coupled rotation occurring during the pivot shift (using a previously validated surgical navigation based methodology) in 35 consecutive patients undergoing hamstrings ACL reconstruction. 17 patients had a standard single-bundle reconstruction and 18 patients a 4-tunnel, 2-bundle reconstruction. 10 pivot shift tests were performed pre- and post operatively by a single operator and the differences compared. Results: The two groups were equally age and sex matched. There was no difference in pre-operative pivot shift measurements. 2-bundle reconstruction decreased the tibial rotation occurring with the pivot shift test more than single-bundle reconstruction (Table 1). There was no detectable difference in the control of tibial translation. Conclusions: This study quantifies, in-vivo, the differences between single and 2-bundle ACL reconstruction in controlling pivot shift. It suggests that anatomic, 2-bundle ACL reconstructions could reduce pivot instability more effectively than a single-bundle. Whether the 10% additional control of the rotational component of the pivot improves functional stability or is necessary every patient and, in the longer term, limits the development of gonarthrosis secondary to abnormal motions, remains to be seen

Tibial and femoral bone tunnel widening (TW) has been observed following anterior cruciate ligament (ACL) reconstruction. We developed a χ12 mm cannulated cancellous screw (Intercondylar Ligament Screw, ICLS) for femoral fixation to reduce TW. The purpose of this study is to introduce our surgical method and its results. We employed an original ICLS system developed to reduce the needed distance between the tibial and femoral-fixation points (distance between fixation points, DbF) in ACL reconstruction. Five-strand (sometimes four or six-strand) hamstring grafts are connected to the ICLS. Tibial fixation is achieved with a Ligament Tension Screw, which had been developed by Murase et al. rom 2001 to 2008, 169 knees underwent ACL reconstruction at our hospitals using our ICLS system. TW was evaluated by radiographs at least three months postoperatively. An enlargement of more than 2 mm was considered TW. The following was also evaluated: range of motion, the limb symmetry index (LSI, injured leg divided by uninjured and multiplied by 100), value of knee extension power in OKC, anterior knee laxity, Lysholm score, and DbF. The average length of DbF was 38.1 mm (n=132). Only 6.7% (n=104) of cases showed more than 2 mm of TW. Mean LSI was 83.3%(n=77) four months postoperatively. The mean Lysholm score was 96.2(n=68) at three months after ACL reconstruction. The mean side-to-side difference in anterior tibial translation, measured with use of a KT-2000 or Knee Lax, was 1.60 mmï1/4N=57ï1/4‰. We were able to reduce TW after ACL reconstruction using our ICLS system with good results

Anterior cruciate ligament (ACL) reconstruction has traditionally been performed using a single bundle (SB) technique, providing good to excellent results in most cases . There is some evidence from biomechanical studies that double bundle (DB) techniques may improve anteroposterior and rotational stability. A number of prospective randomised trials have been performed producing conflicting results. The aim of this study was to find out any differences in outcome between single bundle and double bundle ACL reconstruction. A systematic review was performed to compare the evidence pertaining to the outcomes of double bundle versus single bundle ACL reconstruction methods. Medline (1966 onwards), EMBASE (1980 onwards) and the Cochrane database were searched, retrieving 9,568 possible articles. Only 6 studies fulfilled all the inclusion criteria. To be included, the study had to be prospective and randomised, comparing double bundle and single bundle grafts inserted using an arthroscopically assisted technique and have a minimum 12 month follow-up period for all patients. Analysis was performed using Review Manager (RevMan) [Computer program]. Version 5.0. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2008. Five hundred and sixty patients (341 single bundle and 219 double bundle reconstructions) were considered for statistical analysis from these six papers. There was a significant difference between the groups with the double bundle reconstruction showing less of pivot shift positivity (P< 0.03). The DB group had significantly greater antero-posterior stability on KT arthrometer testing (P=0.002). Double bundle ACL reconstruction improved both antero-posterior and rotational stability. There was also significant improvement in IKDC scores in patients with double bundle ACL reconstruction compared to single bundle reconstruction

After anterior cruciate ligament (ACL) rupture, reconstructive surgery with a hamstring tendon autograft is often performed. Despite overall good results, ACL re-rupture occurs in up to 10% of the patient population, increasing to 30% of the cases for patients aged under 20 years. This can be related to tissue remodelling in the first months to years after surgery, which compromises the graft's mechanical strength. Resident graft fibroblasts secrete matrix metalloproteinases (MMPs), which break down the collagen I extracellular matrix. After necrosis of these fibroblasts, myofibroblasts repopulate the graft, and deposit more collagen III rather than collagen I. Eventually, the cellular and matrix properties converge towards those of the native ACL, but full restoration of the ACL properties is not achieved. It is unknown how inter-patient differences in tissue remodelling capacity contribute to ACL graft rupture risk. This research measured patient-specific tissue remodelling-related properties of human hamstring tendon-derived cells in an in vitro micro-tissue platform, in order to identify potential biological predictors for graft rupture. Human hamstring tendon-derived cells were obtained from remnant autograft tissue after ACL reconstructions. These cells were seeded in collagen I gels on a micro-tissue platform to assess inter-patient cellular differences in tissue remodelling capacity. Remodelling was induced by removing the outermost micro-posts, and micro-tissue compaction over time was assessed using transmitted light microscopy. Protein expression of tendon marker tenomodulin and myofibroblast marker α-smooth muscle actin (αSMA) were measured using Western blot. Expression and activity of remodelling marker MMP2 were determined using gelatin zymography. Cells were obtained from 12 patients (aged 12–51 years). Patient-specific variations in micro-tissue compaction speed or magnitude were observed. Up to 50-fold differences in αSMA expression were found between patients, although these did not correlate with faster or stronger compaction. Surprisingly, tenomodulin was only detected in samples obtained from two patients. Total MMP2 expression varied between patients, but no large differences in active fractions were found. No correlation of patient age with any of the remodelling-related factors was detected. Remodelling-related biological differences between patient tendon-derived cells could be assessed with the presented micro-tissue platform, and did not correlate with age. This demonstrates the need to compare this biological variation in vitro - especially cells with extreme properties - to clinical outcome. Sample size is currently increased, and patient outcome will be determined. Combined with results obtained from the in vitro platform, this could lead to a predictive tool to identify patients at risk for graft rupture

The options for treatment of the young active patient with isolated symptomatic osteoarthritis of the medial compartment and pre-existing deficiency of the anterior cruciate ligament are limited. The potential longevity of the implant and levels of activity of the patient may preclude total knee replacement, and tibial osteotomy and unicompartmental knee arthroplasty are unreliable because of the ligamentous instability. Unicompartmental knee arthroplasties tend to fail because of wear or tibial loosening resulting from eccentric loading. Therefore, we combined reconstruction of the anterior cruciate ligament with unicompartmental arthroplasty of the knee in 15 patients (ACLR group), and matched them with 15 patients who had undergone Oxford unicompartmental knee arthroplasty with an intact anterior cruciate ligament (ACLI group). The clinical and radiological data at a minimum of 2.5 years were compared for both groups. The groups were well matched for age, gender and length of follow-up and had no significant differences in their pre-operative scores. At the last follow-up, the mean outcome scores for both the ACLR and ACLI groups were high (Oxford knee scores of 46 (37 to 48) and 43 (38 to 46), respectively, objective Knee Society scores of 99 (95 to 100) and 94 (82 to 100), and functional Knee Society scores of 96 and 96 (both 85 to 100). One patient in the ACLR group needed revision to a total knee replacement because of infection. No patient in either group had radiological evidence of component loosening. The radiological study showed no difference in the pattern of tibial loading between the groups. The short-term clinical results of combined anterior cruciate ligament reconstruction and unicompartmental knee arthroplasty are excellent. The previous shortcomings of unicompartmental knee arthroplasty in the presence of deficiency of the anterior cruciate ligament appear to have been addressed with the combined procedure. This operation seems to be a viable treatment option for young active patients with symptomatic arthritis of the medial compartment, in whom the anterior cruciate ligament has been ruptured

Most people have not returned to their pre-injury level of sports participation 12 months following anterior cruciate ligament (ACL) reconstruction surgery. Twelve months may be too early to assess return to sport outcomes accurately. The purpose of this study was to evaluate the mid-term return to sport outcomes following ACL reconstruction surgery. A self-report questionnaire was used to collect data from people at 2 to 7 years following ACL reconstruction surgery regarding pre-injury sports participation, post-operative sports participation and subjective knee function. The main inclusion criteria were participation in regular sports activity prior to surgery and the attendance of routine surgical follow up appointments. A total of 314 people were included at a mean 39.6 ± 13.8 months following ACL reconstruction surgery. At follow up, 45% of people were playing sport at their pre-injury level and 29% were playing competitive sport. Of those playing competitive sport prior to injury, 46% were playing competitive sport at follow up. Ninety three percent of people had attempted sport at some time following their ACL reconstruction surgery. People who had not attempted their pre-injury level of sport by 12 months following surgery were just as likely to have returned to pre-injury level by 39 months after surgery as those who had played sport by 12 months (risk ratio, 95% CI = 1.1, 0.76–1.6). Less than 50% of people had returned to either their pre-injury level of sport or competitive sport when surveyed at 2 to 7 years following ACL reconstruction surgery. Sporting activity at 12 months was not predictive of participation at 2 to 7 years, suggesting that people who return to sport within 12 months may not maintain their sports participation

Aims: The aims of this study were to define the incidence of knee stiffness following ACL reconstruction, to determine which patient factors were associated with this, and to assess how effective arthroscopic arthrolysis has been in treating the stiffness. Methods: To define the incidence of stiffness, we reviewed the patient records of a consecutive cohort of 100 primary isolated ACL reconstructions using quadruple hamstring autografts (2004–2006). Stiffness was defined as any loss of motion as compared to the contra-lateral leg. The mean age at reconstruction was 30 years and the median delay between injury and operation was 15 months. To assess the effectiveness of arthroscopic arthrolysis, we then reviewed all the patients who had undergone this procedure following primary isolated ACL reconstruction (n=18: 1997–2008). The mean age at arthrolysis was 31 years and the median delay between reconstruction and arthrolysis was nine months. Results: Following primary ACL reconstruction, the incidence of stiffness was 12% six months postoperatively. Poor compliance with physiotherapy (p< 0.005), previous knee surgery (p< 0.005), and anterior knee pain (p< 0.029) were significantly associated with stiffness. A binary logistic regression found both poor compliance with physiotherapy (Exp(B)=6.931; 95%CI, 1.609–29.859; p< 0.009) and previous knee surgery (Exp(B)=6.383; 95%CI, 1.548–26.322; p< 0.010) to be significant predictors of the stiffness. The rate of stiffness fell to 5% at 12 months, without operative intervention. Of the 18 patients who underwent arthroscopic arthrolysis, the mean extension loss improved from 7° to 1° and the mean flexion loss improved from 8° to 2°. Arthroscopic arthrolysis was significantly more effective in restoring extension loss (p< 0.029) if carried out within eight months of the primary reconstruction. Conclusions: Knee stiffness remains a significant problem post ACL reconstruction. This can however be effectively improved by appropriately timed arthroscopic arthrolysis

Purpose of Study: To examine if and when patients return to sporting activity following surgery, and how their subjective assessment of ability to perform activities was affected by their injury and surgery. We also wished to examine if there was any difference in the timing of return to sport between different sporting activities and by graft (hamstring or bone, patella tendon, bone (BTB)) used for ACL reconstruction. Method and Results: 252 ACL reconstructions were followed up for 2.5 years post surgery. They were evaluated pre and post surgery with Mohtadi activity scores evaluating their function for their primary and secondary sporting activities. They were also evaluated regards exactly when they got back if at all to their primary and secondary activities. 84.2% returned to activity1 at a mean of 9.3 months 87.2% returned to activity 2 at a mean of 8.5 months. 60.7% of patients who returned to activity 1 returned at the same level as prior to their injury. 69.8% of those who returned to activity 2 returned at the same level as prior to their injury. There was no significant difference in timing of return to sport between hamstring and BTB graft. Discussion: We can conclude from this study that the mean time to return to sport following ACL reconstruction is close to what most surgeons) are telling their patients (i.e. 6 to 9 months). However there is wide variation between subjects with a number of complex factors affecting when a person returns to their activity. It is probably wrong for us to give the expectation to all patients that they will be back to their preferred activities at 6 to 9 months

The purpose of this investigation was to evaluate systematically the literature concerning biopsy, MRI signal to noise quotient (SNQ) and clinical outcomes in graft-maturity assessment after autograft anterior cruciate ligament reconstruction (ACLR) and their possible relationships. Methods: The systematic review was reported and conducted according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Studies through May 2019 evaluating methods of intra-articular ACL autograft maturity assessment were considered for inclusion. Eligible methods were histologic studies of biopsy specimens and conventional MRI studies reporting serial SNQ and/ or correlation with clinical parameters. Ten biopsy studies and 13 imaging studies, with a total of 706 patients, met the inclusion criteria. Biopsy studies show that graft remodeling undergoes an early healing phase, a phase of remodeling or proliferation and a ligamentization phase as an ongoing process even 1 year after surgery. Imaging studies showed an initial increase in SNQ, peaking at approximately 6 months, followed by a gradual decrease over time. There is no evident correlation between graft SNQ and knee stability outcome scores at the short- and long-term follow-up after ACLR. The remodeling of the graft is an ongoing process even 1 year after ACLR, based on human biopsy studies. MRI SNQ peaked at approximately 6 months, followed by a gradual decrease over time. Heterogeneity of the MRI methods and technical restrictions used in the current literature limit prediction of graft maturity and clinical and functional outcome measures by means of MRI graft SNQ after ACLR