The Anterior Cruciate Ligament (ACL) plays a vital role in maintaining function and stability in the knee. Over the last several decades, much research has been focused on elucidating the anatomy, structural properties, biomechanics, pathology, and optimal treatments for the ACL. Through careful and objective study, the ACL can be understood to be a dynamic structure, rich in neurovascular supply. Although it is referred to as one ligament, it is comprised of two dis-tinct bundles which function synergistically to facilitate normal knee kinematics. The bony morphology of the knee defines normal knee kinematics, as well as the nature of the soft-tissue structures about the knee. Characterized by individual uniqueness, bony morphology varies from patient to patient. The ACL, which is a reflection of each patient's unique bony morphol-ogy, is inherently subject to both anatomic and morphologic variation as well. Furthermore, the ACL is subject to physiologic aging, which can affect the anatomic and structural properties of the ligament over time. A successful anatomic ACL Reconstruction, which may be considered the functional restoration of the ACL to its native dimensions, collagen orientation, and inser-tion sites according to individual anatomy, considers all these principles. It is vital to respect the nature we observe, rather than to “create” nature to fit a one-size-fits-all surgery. Double bundle ACL Reconstruction may therefore be thought of more as a concept rather than a specific technique, one that respects the individual unique anatomy of each patient to provide a truly indi-vidualized, anatomic, and value-based ACL Reconstruction

The management of symptomatic single bundle Anterior Cruciate Ligament (ACL) ruptures is still a surgical dilemma. Preservation of the intact fibres of the ACL bundle is considered to be a possible source of reinnervation of the ACL autograft which reflects on better proprioceptive knee control after major ligament reconstruction. Results of a prospective study of 67 patients who had a double stranded but single bundle Anterior Cruciate Ligament (ACL) reconstruction for partial ACL ruptures are presented. There were 43 males and 24 females in this study with a mean age at the time of injury of twenty-five years (14 – 40). Eight played sport professionally and thirty-four played at a competitive level. A valgus twisting force was the most common mechanism of injury. Mean injury to operation time was 7.5 weeks (2–12). All procedures were done arthroscopically without using tourniquet, but using an arthroscopy pump and irrigation fluid containing adrenaline. The semitendinosis hamstring graft was used in all reconstructions. The mean follow-up period was 3.3 years (2–5.4). There was one major complication, who developed a reflex sympathetic dystrophy following a saphenous nerve neuroma. The Quality of Life (QOL) score was assessed using the Mohtadi index. The mean pre-operative QOL score of 30 (13–50) was improved to 93 (70–100) post-operatively. Fifty patients were able to return to their previous sporting level at a mean duration of 9 months (6–12). Preservation of mechanoreceptors by performing a double stranded, single bundle ACL reconstruction in partial ACL ruptures in high demand patients yields good results and enables early return to high demand sports

Don O’Donoghue (1950) described a particular acute injury of the knee in athletes (“also of high school age”) that he described as “an unhappy triad”. It consisted of: 1) rupture of the Medial Collateral Ligament (MCL), 2) damage to the Medial Meniscus (MM) and 3) rupture of the Anterior Cruciate Ligament (ACL). We have reviewed the arthroscopic findings of 34 consecutive knees (ages 12 to 16 years) with complete rupture of the ACL. In 21 cases the injury was acute, and the remaining were chronic of had had more than one traumatic episode at the time of arthroscopy. Out of the 34 cases, 26 had associated meniscal injuries: 4 MM; 14 Lateral Meniscus (LM) and 8 MM plus LM. Acute ACL injuries were associated mainly with LM damage (MM/LM: 1/5) whereas, in the chronic injuries, there were no such differences (MM/LM: 1/1). Out of the 21 acute LCA injuries there were 17 cases of acute rupture of the MCL. Conclusions: 1- Contrary to what has been widely accepted, also in pre-adolescent and adolescent, Acute ACL ruptures are more frequently associated with LM damage that with MM tears. 2- Most injuries of the MM associated to ACL injuries (particularly “bucket handle” tears) are the result of a previously ACL unstable knee

Abstract

Purpose: To determine if patients randomized to a knee immobilizer following a primary hamstring tendon anterior cruciate ligament (ACL) reconstruction have lower visual analog scale (VAS) pain scores at day two postoperative than patients who do not wear a knee immobilizer. Method: Patients aged 18–40 with symptomatic ACL deficiency as determined by MRI or physical exam who met the study inclusion criteria were eligible. Patients meeting intra-operative inclusion critiera were randomized (immobilizer or no immobilizer) during wound closure. The immobilizer used was a soft unhinged brace with velcro straps and three metal bars (Breg). Pre, intra and post operative protocols were standardized. Analgesic use and VAS scores were recorded at: one hour after surgery, 8am and 8pm for the first two days postoperative, and 5pm for days 3–14 postoperative. Patients were examined by the surgeon within 14–28 days postoperative. Based on a published survey and the literature, the primary outcome was patient self-assessed pain using a 0–100mm VAS (no pain-worst pain) at day 2 postoperative. Secondary outcomes included: analgesic use, complications, and range of motion. A sample size estimate was calculated resulting in 44 patients per group. A total of 102 patients were enrolled; 88 randomized and 14 excluded intra-operatively. Recruitment was achieved within 11 months. Results: There was no difference in mean VAS pain scores at 2 days post-operative between immobilized and non-immobilized patients (32.6 and 35.2, respectively; p=0.59, 95% CI −6.99, 12.3). Regardless of group allocation, the greatest pain reported was on the evening of day 1 post-operative. Throughout the first week, patients medicated to a pain level of approximately 30/100. There were no differences between groups in medication consumed, range of motion or complications. At 2 days post-operative all patients randomized to the immobilizer group reported that they worn their brace 76–100% of the time. Conclusion: No differences in pain were detected between immobilized and non-immobilized patients at any point during 14 days post ACL reconstruction. Based on these findings, a knee immobilizer is not recommended post-operatively for pain control. This study does not address other reasons for immobilizer use such as graft protection or range of motion

Introduction: The aim of this study was to evaluate whether a guiding pin for a femoral tunnel could be positioned through the tibial tunnel into the center of the anatomical ACL attachment.

Material and Methods: We studied 77 knees who underwented arthroscopic ACL reconstruction with hamstrings. The femoral tunnel was drilled through an antero-medial portal at the center of the anatomic insertion at about 10 resp. 2 o’clock position. Tibial tunnel (mean diameter 7.55 ± 0.54 mm ) was drilled at 90° of knee flexion. The aiming point was on a line, being a “prolongation” of the posterior border of the anterior horn of the lateral meniscus and at exactly 60% of the distance from the end of the anterior horn of the lateral meniscus and the medial tibial spine. Then, through the tibial tunnel, a 4mm offset femoral drill guide was positioned as close as possible to the femoral tunnel and a 2.5 mm guide wire was drilled. The position of the guide wire was photographed arthroscopically and the deviation was measured as distance between the center of the femoral tunnel and guide wire.

Results: The mean angle of the tibial tunnel in the coronar plain was 27,53° and in the sagittal plain 25,84°, both according to the longitudinal axis of the tibia. In 74 knees ( 96. 1 % ) the guidewire did not reach the femoral tunnel. Only in 3 knees it reached the superomedial edge of the femoral tunnel. The mean deviation was 4.50 ± 1.54 mm (p = 0.00000004 ). No statistical relationship was found between deviation and tibial tunnel inclination angles or tibial tunnel diameter.

Conclusion: Transtibial femoral tunnel drilling did not reach the anatomic side of the ACL insertion in most of the cases, even with larger tibial tunnels (for hamstring grafts up to 8.5 mm). Therefore we recommend tibial tunnel drilling through the anteromedial portal.

Abstract

INTRODUCTION

ACL retaining (BCR) Total Knee Arthroplasty (TKA) provides more normal kinematics than ACL sacrificing (CR) TKA. However, in the native knee the ACL and the asymmetric shape of the tibial articular surface with a convex lateral plateau are responsible for the differential medial/lateral femoral rollback (medial pivot). Therefore, the hypothesis of this study was that an asymmetric biomimetic articular surface together with ACL preservation would better restore native knee kinematics than retention of the ACL alone. Normal knee kinematics from bi-planar fluoroscopy was used to reverse engineer the tibial articular surface of the biomimetic implant. This was achieved by moving the femoral component through the healthy knee kinematics and removing material from a tibial template.

Abstract

Introduction and Objective

Objectives: To determine the effectiveness of LIA compared to ACB in providing pain relief and reducing opiates usage in hamstring graft ACL reconstructions.

Introduction: The International Knee Documentation Committee (IKDC) recommends use of the IKDC score to document subjective, objective and functional ACL outcome. To further improve knowledge concerning patient QOL after ACL reconstruction, an additional specific QOL questionnaire was developed. Using a combination of univariate and multivariate analysis the patient factors and surgical factors that influenced QOL 5- years after ACL reconstruction were determined.

Materials: 500 patients operated on for arthroscopic ACL reconstruction at our institution between 1997 and 2001 were prospectively enrolled. Patient psychosocial profile, sport expectations, knee exam, type of graft, associated lesion, type of anesthesia, complications, IKDC, KT 2000 at 6 moths, 1 year and 2 years were recorded. At five years, patients were asked to complete a 5-subscale validated QOL questionnaire for ACL deficiency. A multivariate analysis was performed to identify the factors influencing 5-year QOL.

Results: 203 patients completed the 5-years QOL questionnaire. Responders did not statistically differ from non responders. Patient subjective factors such as: patient expectations, pre-operative symptoms, work-school concerns, recreations concerns, social and psycho-social concerns were significantly (p< 0.05) and independently associated with the five-year QOL results. Objective factors such as meniscus tears and results of the KT 2000 (p< 0.05) were the two surgical factors correlated with 5-year QOL.

Discussion: In this large prospective study, most of the factors influencing the 5-year QOL results after ACL reconstruction were related to patient expectations, psycho-social, symptoms and work-sport concerns. The presence of a meniscus tear and greater KT 2000 laxity also contributed to poorer 5-year QOL results.

ACL deficiency can have detrimental pathological effects on the menisci in the knee. A database review in Quebec over a three-year period was previously reported (Canadian Academy of Sport Medicine, Winnipeg, 2003), which examined the relationship between waiting times for ACL surgery and the requirement of a meniscal procedure. The purpose of this study is to determine if the length of time between an index injury and ACL reconstruction (ACLR) surgery correlates with the incidence of meniscal repair and meniscectomy in Alberta, and to compare the results to those of the Quebec study.

Retrospective study, using procedure and billing codes to search the Alberta Health and Wellness databases for knees undergoing primary ACLR surgery between 2002–2005. Inclusion: Patients sixteen years or older at time of reconstruction. Exclusion: Revision ACLR, duplicate billing and coding, and insufficient database information. For each reconstructed knee, databases were searched for initial injury evaluation date with primary care physician, dates of meniscectomy or meniscal repair procedures, and date of ACLR.

Over a three-year period, there were 3382 primary ACL reconstructions performed in Alberta, 3812 ACLR in Quebec. Of these patients, 2583 in Alberta (76%) and 1722 in Quebec (45%) required a meniscal procedure. On average, Albertans waited 1389 days from injury to ACLR compared to 422 days in Quebec. In Alberta, patients not requiring a meniscal procedure waited 1212 days, patients requiring meniscal repair waited 1143 days, and patients requiring meniscectomy waited 1519 days, compared to 251, 413 and 676 days in Quebec, respectively. Three percent of patients in Alberta had ACLR < three months after injury (114 patients), with 45% requiring meniscectomy. Overall, 61% of patients in Alberta required a meniscectomy for significant meniscal injury, compared to 48% of patients in Quebec. The proportions for each province were statistically significant.

Compared to Quebec, patients in Alberta are waiting longer for ACLR, with only a small proportion of cases being treated acutely. The proportion of patients requiring surgery for significant meniscal injury is also greater in Alberta. The higher proportion of patients in Alberta requiring meniscectomy may be due to the delay in ACLR.

Introduction: Instrumented arthrometry is a widely used technique for the quantification of cruciate ligament laxity. It is used both before and after surgery. The Rolimeter(Aircast, Europe) is used in such scenarios. It has several advantages over its cousins; it is more compact, lighter, less expensive and amenable to sterilization techniques. The other leading arthrometers have however had over 15 years of clinical use and their reliability has been thoroughly assessed. Muellner et al found no significant difference in the intra-tester and inter-tester results obtained on Rolimeter assessment of the knees of un-injured healthy subjects. Our study assessed the inter-tester and intra-tester variability when the Rolimeter is applied to patients with unilateral ACL-deficient knees. It also examines whether the level of experience of the examiner influences the results in this group of patients.

Materials and Methods: Six examiners each examined thirty-three subjects on two occasions. One examiner was medically qualified but had never performed a Lachman or anterior drawer test. Two examiners were qualified physiotherapists who routinely examined knees, but had never used a Rolimeter. One medically qualified examiner was considered to be of intermediate experience.Two examiners were regarded as expert Rolimeter users.For each examination a Rolimeter reading was taken three times with the knee at 30 degrees of flexion and three times at 90 degrees of flexion for both knees.The interval between examinations was at least thirty minutes. All the readings were acquired on the same day. The examiners were blinded to whether the subject was known to be ACL deficient or not. The results of the examinations were entered onto a data-base.Repeated measures analysis of variance was used to test for the effects of the following factors, difference between examiners, reproduction of results between examinations.

Results: There was no significant difference between each set of measures for each subject between examinations (p=0.767), indicating that the measurement procedure was reliable. Measurements were significantly higher in patients with ACL-deficient knees compared to the control group (p< 0.001) confirming the sensitivity of the Rolimeter to help diagnose ACL-deficient knees. The in-experienced examiner’s measurements were lowest and were more reliable. The examiner with the intermediate experience was the most un-reliable. Both experienced examiners were in close agreement.

Conclusion: We have demonstrated that the rolimeter is reliable in the assesment of ACL deficient patients regardless of the experience of the examiner.

Anterior knee instability associated with rupture of ACL is a disabling clinical problem, especially in the athletic individual. The gracilis and semitendinosus tendon (T4) represent an alternative autograft donor material for reconstruction of the ACL.

The aim of our study was to elaborate a CPG to assist physiotherapists in decision making and to improve the efficacy and uniformity of care for patients with ACL reconstruction with T4.

The CPG was developed according to international methods of guideline development. To identify “best evidence” a structured search was performed. When no evidence was available, consensus between experts (physiotherapist and orthopaedic surgeons) was achieved to develop the guideline. To identify “best clinical experience” and “physiopathology reasoning” focus group of practicing physiotherapists was used. They reviewed the clinical applicability and feasibility of the guideline, and their comments were used to improve it.

CPG include three phases determined from the evidence, physiopathology reasoning and the biological process of autograft (weeks after the surgery: 2^a–6^a, 6^a–10^a and 10^a–16^a). The recommendations included: In postoperative weeks (2^a–6^a) physiotherapy focused on early range of motion of the knee; manual therapy (passive range of motion (PROM) 0–120° and miofascial techniques), pulsed ultrasound of low intensity with a power of 0.3w/cm2 (1MHz) during 10min/day in tibial tunnel, early active hamstring beginning with static weight bearing co-contractions (closed-kinetic-chain) and adductors, partial weight bearing with crutches, exercises in the swimming pool and cryotherapy to pain control (30 mi/4 hours). In weeks 6 to 10, full weight bearing, manual therapy (PROM 0–140° and miofascial techniques), hamstring strengthening progress complexity and repetitions of co-contractions, electrotherapy hamstring and quadriceps co-contractions. Starting at week 10, progress to more dynamic activities/movements, proprioceptive work, open-kinetic-chain, stationary bike and Theraband squats. In week 12, progress jogging program and plyometric type activities. The patients performed sports-specific exercises by about 3½ months postoperative.

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

Aims. The aim of this study was to determine the risk of tibial eminence avulsion intraoperatively for bi-unicondylar knee arthroplasty (Bi-UKA), with consideration of the effect of implant positioning, overstuffing, and sex, compared to the risk for isolated medial unicondylar knee arthroplasty (UKA-M) and bicruciate-retaining total knee arthroplasty (BCR-TKA). Methods. Two experimentally validated finite element models of tibia were implanted with UKA-M, Bi-UKA, and BCR-TKA. Intraoperative loads were applied through the condyles, anterior cruciate ligament (ACL), medial collateral ligament (MCL), and lateral collateral ligament (LCL), and the risk of fracture (ROF) was evaluated in the spine as the ratio of the 95. th. percentile maximum principal elastic strains over the tensile yield strain of proximal tibial bone. Results. Peak tensile strains occurred on the anterior portion of the medial sagittal cut in all simulations. Lateral translation of the medial implant in Bi-UKA had the largest increase in ROF of any of the implant positions (43%). Overstuffing the joint by 2 mm had a much larger effect, resulting in a six-fold increase in ROF. Bi-UKA had ~10% increased ROF compared to UKA-M for both the male and female models, although the smaller, less dense female model had a 1.4 times greater ROF compared to the male model. Removal of anterior bone akin to BCR-TKA doubled ROF compared to Bi-UKA. Conclusion. Tibial eminence avulsion fracture has a similar risk associated with Bi-UKA to UKA-M. The risk is higher for smaller and less dense tibiae. To minimize risk, it is most important to avoid overstuffing the joint, followed by correctly positioning the medial implant, taking care not to narrow the bone island anteriorly. Cite this article: Bone Joint Res 2022;11(8):575–584

Aims. A functional anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) has been assumed to be required for patients undergoing unicompartmental knee arthroplasty (UKA). However, this assumption has not been thoroughly tested. Therefore, this study aimed to assess the biomechanical effects exerted by cruciate ligament-deficient knees with medial UKAs regarding different posterior tibial slopes. Methods. ACL- or PCL-deficient models with posterior tibial slopes of 1°, 3°, 5°, 7°, and 9° were developed and compared to intact models. The kinematics and contact stresses on the tibiofemoral joint were evaluated under gait cycle loading conditions. Results. Anterior translation increased in ACL-deficient UKA cases compared with intact models. In contrast, posterior translation increased in PCL-deficient UKA cases compared with intact models. As the posterior tibial slope increased, anterior translation of ACL-deficient UKA increased significantly in the stance phase, and posterior translation of PCL-deficient UKA increased significantly in the swing phase. Furthermore, as the posterior tibial slope increased, contact stress on the other compartment increased in cruciate ligament-deficient UKAs compared with intact UKAs. Conclusion. Fixed-bearing medial UKA is a viable treatment option for patients with cruciate ligament deficiency, providing a less invasive procedure and allowing patient-specific kinematics to adjust posterior tibial slope. Patient selection is important, and while AP kinematics can be compensated for by posterior tibial slope adjustment, rotational stability is a prerequisite for this approach. ACL- or PCL-deficient UKA that adjusts the posterior tibial slope might be an alternative treatment option for a skilled surgeon. Cite this article: Bone Joint Res 2022;11(7):494–502

Aims

To fully quantify the effect of posterior tibial slope (PTS) angles on joint kinematics and contact mechanics of intact and anterior cruciate ligament-deficient (ACLD) knees during the gait cycle.

Aims

The aim of this study was to compare a bicruciate-retaining (BCR) total knee arthroplasty (TKA) with a posterior cruciate-retaining (CR) TKA design in terms of kinematics, measured using fluoroscopy and stability as micromotion using radiostereometric analysis (RSA).

Aims

The aim of this systematic review and meta-analysis was to gather epidemiological information on selected musculoskeletal injuries and to provide pooled injury-specific incidence rates.