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

We used immediate post-operative in vivo three-dimensional computed tomography to compare graft bending angles and femoral tunnel lengths in 155 patients who had undergone single-bundle reconstruction of the anterior cruciate ligament using the transtibial (n = 37), anteromedial portal (n = 72) and outside-in (n = 46) techniques.

The bending angles in the sagittal and axial planes were significantly greater but the coronal-bending angle was significantly less in the transtibial group than in the anteromedial portal and outside-in groups (p < 0.001 each). The mean length of the femoral tunnel in all three planes was significantly greater in the transtibial group than the anteromedial portal and outside-in groups (p < 0.001 each), but all mean tunnel lengths in the three groups exceeded 30 mm. The only significant difference was the coronal graft- bending angle in the anteromedial portal and outside-in groups (23.5° vs 29.8°, p = 0.012).

Compared with the transtibial technique, the anteromedial portal and outside-in techniques may reduce the graft-bending stress at the opening of the femoral tunnel. Despite the femoral tunnel length being shorter in the anteromedial portal and outside-in techniques than in the transtibial technique, a femoral tunnel length of more than 30 mm in the anteromedial portal and outside-in techniques may be sufficient for the graft to heal.

Cite this article: Bone Joint J 2014;96-B:743–51.

Aims. The aim of this study was to compare patient-reported outcomes (PROMs) following isolated anterior cruciate ligament reconstruction (ACLR), with those following ACLR and concomitant meniscal resection or repair. Methods. We reviewed prospectively collected data from the UK National Ligament Registry for patients who underwent primary ACLR between January 2013 and December 2022. Patients were categorized into five groups: isolated ACLR, ACLR with medial meniscus (MM) repair, ACLR with MM resection, ACLR with lateral meniscus (LM) repair, and ACLR with LM resection. Linear regression analysis, with isolated ACLR as the reference, was performed after adjusting for confounders. Results. From 14,895 ACLR patients, 4,400 had two- or five-year Knee injury and Osteoarthritis Outcome Scores (KOOS) available. At two years postoperatively, the MM repair group demonstrated inferior scores in KOOS pain (β = −3.63, p < 0.001), symptoms (β = − 4.88, p < 0.001), ADL (β = − 2.43, p = 0.002), sport and recreation (β = − 5.23, p < 0.001), quality of life (QoL) (β = − 5.73, p < 0.001), and International Knee Documentation Committee (β = − 4.1, p < 0.001) compared with the isolated ACLR group. The LM repair group was associated with worse KOOS sports and recreation scores at two years (β = − 4.264, p < 0.001). At five years, PROMs were comparable between the groups. At five years, PROMs were comparable between the groups. Participants undergoing ACLR surgery within 12 weeks from index injury demonstrated superior PROMs at two and five years. Conclusion. Our study showed that MM repair, and to a lesser extent LM repairs in combination with ACLR, were associated with inferior patient-reported outcome measures (PROMs) compared to isolated ACLR at two years postoperatively, while meniscal resection groups exhibited comparable outcomes. However, by five years postoperation, no significant differences in PROMs were evident. Further longer-term, cross-sectional studies are warranted to investigate the outcomes of ACLR and concomitant meniscal surgery

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

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

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

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

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. 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 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

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

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. 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

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

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

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).

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