Very long-term osteoarthritis rate after anterior cruciate ligament reconstruction: 182 cases with 22-year' follow-up

Effect of Initial Graft Tension on Knee Osteoarthritis Outcomes After ACL Reconstruction: A Randomized Controlled Clinical Trial With 15-Year Follow-up

Background

The graft tension applied during anterior cruciate ligament (ACL) graft fixation (subsequently referred to as initial graft tension) could potentiate posttraumatic osteoarthritis (PTOA) and influence other outcomes.

Purpose/Hypothesis

The purpose of this study was to analyze the effects of initial graft tension on imaging and patient-reported outcomes related to PTOA 15 years postreconstruction surgery. Clinical and functional outcomes were also assessed. It was hypothesized that (1) the high-tension group would have improved imaging findings and outcomes compared with the low-tension group at 15-year follow-up and (2) the imaging findings and outcomes for the high-tension group would be equivalent to the sex-, race-, age-, and activity level matched control group.

Study Design

Randomized controlled trial; Level of evidence, 1.

Methods

Consented patients underwent ACL reconstruction (ACLR) with bone-patellar tendon-bone or a 4-strand hamstring tendon autograft. A matched uninjured control group was assembled for comparison. Two laxity-based tensioning procedures were randomized: (1) tension set to restore normal anteroposterior (AP) laxity at time of surgery relative to the contralateral uninjured knee (low-tension group) or (2) tension set to overconstrain AP laxity at time of surgery relative to the contralateral knee (high-tension group). Baseline outcome measures, radiographs, and magnetic resonance imaging (MRI) scans were collected prior to surgery and at 15 years postoperatively.

Results

For medial joint space width, the differences between limbs across the 3 groups were not significant. Within the tension groups, the Whole Organ MRI Score was significantly higher in the surgical knee relative to the contralateral knee in both groups, while the Osteoarthritis Research Society International radiographic scores were higher in the surgical knee in the low-tension group only. A total of 43% of patients in both tension groups met the Knee injury and Osteoarthritis Outcome Score composite criteria for a symptomatic knee compared with controls (10%; P = .01). Most other outcomes, including AP laxity, International Knee Documentation Committee knee examination score, and single-leg hop test were not significantly different between the 3 groups.

Conclusion

The results do not support the hypotheses that patients in the high-tension group would have better chondroprotection compared with the low-tension group and have equivalent outcomes with the matched controls. Overall, the results show that patients undergoing ACLR are more likely to develop PTOA and display inferior outcomes compared with the uninjured matched control group, regardless of graft tension.

ACLR and military service: time to rethink?

Anterior cruciate ligament (ACL) rupture is a common injury that affects young, active individuals, normally managed with reconstruction in this age group. Current UK Armed Forces policy precludes prospective applicants from joining with an anterior cruciate ligament reconstruction (ACLR). This isdue to the perceived risk of premature osteoarthritis (OA), graft rupture or clinical failure, all of which could make the service person medically non-deployable.The most recent evidence shows that an ACL rupture without associated significant meniscal or osteochondral defect has a similar likelihood of developing OA as to that of the uninjured knee after reconstruction at 20 years postoperatively.Applicants should be considered for service following an ACL rupture without significant concurrent meniscal or osteochondral defect who have undergone ACLR and 18 months of rehabilitation. We recommend these applicants to be graded P2 Medically Fully Deployable (MFD) as per the Joint Service Publication (JSP) guidance for service personnel who undergo ACLR.

The impact of concomitant meniscal surgery on the clinical outcomes of anterior cruciate ligament reconstruction

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.

Osteoarthritis After Anterior Cruciate Ligament Reconstruction: A Systematic Review of Contributing Factors and Potential Treatments

Anterior cruciate ligament (ACL) injuries result in abnormal knee motion and long-term joint degradation. ACL reconstruction (ACLR) is done with the aim of restoring normal knee kinematics and slowing the joint degradation process. It does appear that this inevitably happens and can be impacted by a multitude of factors. The aim of this review was to examine the factors that influence the progression of osteoarthritis (OA) after ACLR and examine possible treatments that can aid in slowing that progression. A systematic review was conducted by searching all levels of evidence for all studies in English that assessed risk factors for developing OA after ACL reconstruction, had a minimum follow-up of 10 years, and used radiographical outcomes to measure the presence of OA. Studies on trial treatments to reduce osteoarthritis after ACL reconstruction were also included. It was found that among the factors associated with an increased risk of post-ACLR OA are meniscal lesions, meniscectomy, increased age at the time of ACLR, increased time from injury to surgery, male sex, reduced range of motion, smaller thigh girth, graft complications, and failure. Additionally, in performing the ACLR, anteromedial femoral tunnel placement, higher graft tension, and following guidelines for performing anatomic ACLR have been shown to reduce the risk of OA as well. Patients should be adequately counselled on their risk pre-operatively for informed decision-making. Surgeons should also be aware of potential risk factors and how they can be mitigated.

Changes in co-contraction magnitude during functional tasks following anterior cruciate ligament reconstruction: A systematic review

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) is a common orthopedic surgery procedure whose incidence has increased over the past few decades. Nevertheless, it is believed that neuromuscular control remains altered from the early stages after ACLR to later years. Therefore, the aim of this study was to systematically evaluate the magnitude of co-contraction during functional tasks in subjects with unilateral ACLR.

METHODS

A systematic review design was followed. The search strategy was conducted in PubMed, Scopus, EBSCO, PEDro, Cochrane Library, and Web of Science databases from inception to March 2024. The inclusion criteria involved studies using electromyography (EMG) data to calculate muscle pair activation via the co-contraction index (CCI) in ACLR individuals during functional tasks. The Preferred Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and study quality was evaluated using National Institutes of Health (NIH) Study Quality Assessment Tools.

RESULTS

The search strategy found a total of 792 studies, of which 15 were included in this systematic review after reviewing the eligibility criteria. The magnitude of co-contraction was assessed in a total of 433 ACLR individuals and 206 controls during functional tasks such as hop, drop-land, step-up/step-down, and gait. Overall, approximately 79.6% of individuals who had undergone ACLR exhibited increased levels of co-contraction magnitude in the ACLR limb, while 8.5% showed low co-contraction levels.

CONCLUSIONS

The findings of the review suggest that, during functional tasks, most individuals who have undergone ACLR exhibit changes of co-contraction magnitude in the involved limb.

Eighteen-year outcome of anterior cruciate ligament reconstruction with patellar tendon or hamstring autograft

PURPOSE

To evaluate patient reported outcomes and radiographic arthritic changes of transtibial anterior cruciate ligament reconstruction (ACLR) with either bone-patellar tendon-bone (BPTB) or hamstrings (HS) auto-grafts at a minimum of 15-year follow-up.

METHODS

Ninety-four patients (51 of the HS group, 43 of BPTB group) who were operated between the years 2000 to 2005 in two tertiary referral hospitals were contacted and invited to a retrospective evaluation. The interview included subjective outcomes using the Lysholm knee scoring questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Tegner activity level scale, Visual Analogue Scale (VAS) for pain and patients' satisfaction scale. Knee examination included measurements of motion and stability. Knee radiographs were evaluated for osteoarthritic changes according to the Kellgren-Lawrence (KL) score.

RESULTS

The average evaluation time from surgery was 18.6 years. Subjectively, there was no significant difference between groups except for a better post-operative level of activity and satisfaction in the HS group. Objectively, there was no significant difference between groups in knee stability and range of motion. Most patients had grade KL ≤ 1 radiographic osteoarthritits changes and there was no significant difference between groups. Recurrent complete tear of the reconstructed graft occurred in 3 patients of each group. In both groups 84% had no further surgery while the indications for further surgery were mostly a meniscal tear or tibial hardware removal.

CONCLUSIONS

Very long-term outcomes and clinical stability of transtibial HS or BPTB graft ACL reconstruction are good with low rate of graft failure and radiographic osteoarthritis.

A slight degree of osteoarthritis appears to be present after anterior cruciate ligament reconstruction compared with contralateral healthy knees at a minimum of 20 years: A systematic review of the literature

PURPOSE

The aim of the present systematic review was to quantitatively synthesize the best literature evidence regarding osteoarthritis developing after anterior cruciate ligament reconstruction (ACLR), including only studies with a follow-up duration of at least 20 years.

MATERIAL AND METHODS

A systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines on four electronic databases (PubMed, Scopus, EMBASE and Cochrane Library). The outcome measures extracted from the studies were failure rate, subsequent knee surgery on the same knee, radiographic development of osteoarthritis measured with Kellgren-Lawrence, International Knee Documentation Committee (IKDC) radiographic score and Ahlbäck classification. The health of both the ACLR knee and the contralateral knee was compared.

RESULTS

A total of 1552 patients were included in the study, of which 1290 (83.11%) were operated on using a patellar tendon graft, 190 (12.24%) with hamstrings, 27 (1.73%) with an iliotibial band and 45 (2.89%) with patellar tendon plus a ligament augmentation device (LAD). The mean age at the time of surgery was 25.18 ± 1.91 years, and the mean follow-up time was 23.34 ± 2.56 years. Analysing IDKC Score at final follow-up, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 33.2% (324/976) of the patients showed a moderate to severe degree (Grade C or D) of osteoarthritis, while for Kellgren-Lawrence, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 28.9% (196/678) of the patients showed a moderate to severe degree (Grade III or IV) of osteoarthritis. In total, 1552 patients were registered, 155 reruptures (9.98%) and a total of 300 (19.3%) new surgeries, of which 228 meniscectomy (14.69%), 21 (1.35%) knee arthroplasty and 17 (1.09%) hardware removal were recorded.

CONCLUSIONS

ACL reconstruction appears to result in mild osteoarthritis in the long term in most of the patients and only less than 33.2% develop a moderate to severe degree of knee OA according to IKDC radiographic score. A slight degree of osteoarthritis appears to be present in ACLR knees compared with contralateral healthy knees.

LEVEL OF EVIDENCE

Level IV.

Prevention of knee stiffness following ligament reconstruction: Understanding the role of Arthrogenic Muscle Inhibition (AMI)

The knee is a joint that is often injured in sport, with a large and increasing number of ligament tears and repairs; postoperative complications can lead to poor outcome, such as stiffness. Beyond the well-known and well-described intra- and extra-articular causes of postoperative stiffness, the present study introduces the concept of a central reflex motor inhibition mechanism called arthrogenic muscle inhibition (AMI). AMI occurs after trauma and can be defined as active knee extension deficit due to central impairment of Vastus Medialis Obliquus (VMO) contraction, often associated with spinal reflex hamstring contracture. This explains the post-traumatic flexion contracture that is so common after knee sprain. The clinical presentation of AMI is easy to detect in consultation, in 4 grades from simple VMO inhibition to fixed flexion contracture by posterior capsule retraction in chronic cases. After recent anterior cruciate ligament (ACL) tear, more than 55% of patients show AMI, reducible in 80% of cases by simple targeted exercises initiated in consultation. Practically, in patients who have sustained knee sprain, it is essential to screen for this reflex mechanism and assess reducibility, as AMI greatly aggravates the risk of postoperative stiffness. In case of hemarthrosis, we recommend joint aspiration, which provides immediate benefit in terms of pain and motor inhibition. In case of persistent AMI, classical electrostimulation and "cushion crush", as used by all physiotherapists, are ineffective. To reduce the risk of postoperative stiffness, no surgery should be considered until AMI has resolved. LEVEL OF EVIDENCE: expert opinion.

Ten-year outcomes of anterior cruciate ligament reconstruction with hamstring tendon autograft and femoral fixation with a cortico-cancellous screw suspension device

PURPOSE

To evaluate the clinical and radiographic outcomes of anterior cruciate (ACL) reconstruction at minimum 10-year follow-up.

METHODS

Ninety-three patients who underwent primary unilateral ACL reconstruction with hamstring tendon autograft, transtibial technique and femoral cortico-cancellous screw suspension device (Athrax, Leader Medica s.r.l) between 2010 and 2012 were retrospectively reviewed. Mean follow-up was 136 months. Evaluation was performed using the International Knee Documentation Committee score (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Knee Score and Tegner Activity Level Scale. Incidence of OA was determined by comparing standard anteroposterior and lateral weightbearing radiographs of the ACL-reconstructed and contralateral knee. Osteoarthritis severity was graded according to the Kellgren-Lawrence (KL) score.

RESULTS

Median Tegner activity level was 6 (5-7). Lysholm and IKDC scores were 100 (95-100) and 90 (86-95), respectively, KOOS was 98 (95-100). Of ACL-reconstructed knees, 41 (50%) had radiographic OA, of which 6 (7.3%) had severe OA (KL III). Of the contralateral healthy knees, 28 (34.1%) had radiographic evidence of OA. Of these 22 (26.8%) and 6 (7.3%) patients had, respectively, KL-I and KL-II. 11 patients (11.8%) underwent subsequent knee surgery: 5 (5.4%) revisions, 3 (3.2%) meniscal surgeries, 2 (2.2%) other surgeries, 1 (1.1%) contralateral ACL reconstruction.

CONCLUSIONS

The study demonstrates that ACL reconstruction with HT autograft and cortico-cancellous screw suspension device determines satisfying clinical results after 10 years of follow-up. From our cohort, a low rate of graft failure has been reported, even though almost 50% of patients present a knee OA greater or equal to grade II KL.

Clinical outcome of iterative meniscal suture after ACL reconstruction at a minimum of 2 years' follow-up

INTRODUCTION

Failure rates in meniscal suture associated to ACL reconstruction range from 10 to 26.9%, often leading to meniscectomy. In young patients, the wish to conserve the meniscus may lead to iterative suture, if the lesion allows. There are no data available for clinical results of repeat meniscal suture at the same site as the primary lesion in a stabilized knee. The immediate socioeconomic cost, compared to meniscectomy, needs to be taken into account, and benefit needs to be demonstrated. The main aim of the present study was to assess the rate of secondary meniscectomy after iterative meniscal suture in stabilized knees. The study hypothesis was that failure rates are higher in iterative isolated meniscal suture after ligament reconstruction than in primary repair.

MATERIAL AND METHODS

This single-center retrospective study analyzed patients receiving iterative meniscal suture on stable knee, between 2009 and 2019, with a minimum 26 months' follow-up. Twenty-three patients were analyzed: 15 male, 8 female; mean age at iterative suture, 28.1±7.9 years (range, 14-49 years); mean BMI, 24.2±2.9kg/m2 (range, 19-31). Mean time to recurrence was 38.9±25.1 months (range, 6-93 months). Initial ACL graft used the patellar ligament in 69.6% of cases (n=16) and the hamstrings in 30.4% (n=7). Mean differential laximetry before iterative suture was 1.7±0.3mm (range, 1.2-2.3mm). Iterative suture was in the medial meniscus in 69.6% of cases (16/23) and in the lateral meniscus in 30.4% (7/23). Risk factors for failure, defined by requirement for meniscectomy, were assessed. Functional results were assessed on Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) score and Tegner score.

RESULTS

The failure rate was 48% (11/23), incorporating all lesions together. Bucket-handle tear was most frequently associated with failure (91%; p<0.01). There was significant improvement after iterative suture in subjective IKDC score (51.6±15.2 vs. 81.3±15.6; p<0.001) and KOOS scores: symptoms and stiffness, 66.6±13.7 vs. 91.1±7.53 (p<0.001); pain, 79.2±12.7 vs. 93.4±7.4 (p<0.01); function, 91.3±11.2 vs. 97.9±4.44 (p<0.001); quality of life, 38.1±23.2 vs. 62.3±30.1 (p<0.001).

CONCLUSION

The failure rate for iterative meniscal suture on stabilized knee was 48%. Bucket-handle tear was a major risk factor for failure (91%). Despite these high failure rates, functional results systematically improved.

LEVEL OF EVIDENCE

IV.

Using 3D MRI Bone Shape to Predict Pre-Osteoarthritis of the Knee 2 Years After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Anterior cruciate ligament (ACL) injury increases risks for osteoarthritis (OA), a poorly modifiable and disabling condition. Joint changes of potentially reversible pre-OA have been described just 2 years after ACL reconstruction (ACLR) when early bone shape changes have also been reported.

PURPOSE

This study evaluates relationships between interlimb differences in tibiofemoral bone shape derived from statistical shape modeling (SSM) of magnetic resonance imaging (MRI) and participant factors on patient-reported outcomes 2 years after unilateral ACLR.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

SSM-derived tibiofemoral bone shape and subchondral bone area were assessed from bilateral knee MRI scans of 72 participants with unilateral ACLR (mean age, 34 ± 11 years; 32 women) and compared with a reference cohort of 398 older individuals without OA (mean age, 50 ± 3 years; 213 women). Multivariable logistic regression models examined relationships between participant and surgical factors with interlimb differences in bone shapes or subchondral bone areas. Relationships between patient-reported outcomes and the interlimb differences in bone shape and subchondral area were examined using similar models.

RESULTS

Bone shape scores and subchondral bone areas were greater (more OA-like) in ACLR knees than uninjured contralateral knees in every bone metric tested (P≤ .001). Interlimb differences in femur shape scores of participants with ACLR were 65% greater (P < .001) than those of the significantly older reference cohort. Taller height, medial meniscal tears, and decreasing age were associated with larger interlimb differences in shape scores and subchondral areas (P < .05). Bone-patellar tendon-bone (BPTB) autograft recipients demonstrated greater interlimb subchondral area differences compared with allograft recipients (P < .05). Interlimb differences for hamstring autograft recipients did not differ from those with BPTB or allograft. Greater interlimb differences in medial femur subchondral areas were associated with worse patient-reported Knee injury and Osteoarthritis Outcome Score Symptoms (R = 0.27; P = .040).

CONCLUSION

Even in the absence of radiographic OA, just 2 years after unilateral ACLR patients showed greater bone shape scores and subchondral areas consistent with pre-OA in their ACLR knees. Furthermore, greater medial femur bone areas were weakly associated with worse symptoms. Patients who are younger, are taller, have meniscal tears, or have BPTB grafts may be at increased risk for bony asymmetries 2 years after ACLR.

Construction and validation of a functional diagnostic score in anterior cruciate ligament ruptures of the knee in the immediate post-traumatic period. Preliminary results of a multicenter prospective study

INTRODUCTION

Knee ligament injuries are frequent and their number is constantly increasing with the development of sports activities. Dynamic knee maneuvers usually make it possible to diagnose anterior cruciate ligament (ACL) injuries but they remain difficult to perform in the early post-traumatic phase. This leads to the almost systematic use of MRI scans, many of which turn out to be superfluous. The aim of this study was to construct a screening score based solely on history-taking, in order to help diagnose ACL injuries, and to define thresholds that could help inform recommendations for MRI usage. The hypothesis was that this score could distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries.

MATERIAL AND METHODS

This prospective multicenter study included 166 patients. Patients were included if they were between 18 and 55 years of age, with knee trauma that had occurred in the last 10 days, and without a bone fracture on standard radiographs. They were excluded if the trauma required immediate surgical management and if they had a history of knee trauma. The screening score was completed by the physician. The score included the following items: assessment of pain, immediate post-traumatic functional impairment, notion of a "pop", feeling of instability and presence of a swelling. An MRI was systematically performed and the patient consulted a referring physician to compare the initial score with the diagnosis.

RESULTS

Eighty-six patients had an injured ACL and 80 had a healthy ACL. Two thresholds could be identified. For a score lower than 4, the risk of an ACL injury was low with a sensitivity of 96% and a negative predictive value of 87%. For a score above 8, the ACL injury was highly probable with a specificity of 88% and a positive predictive value of 83%.

DISCUSSION/CONCLUSION

The score was able to distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries. These preliminary results confirm that the selected items are relevant and that the score can help improve the diagnostic orientation of patients with recent knee trauma. Increasing the sample size in combination with an analysis of influencing factors will determine whether the performance of this score can be refined.

LEVEL OF EVIDENCE

II prospective multicenter study.

The Risk Factors and Preventive Strategies of Poor Knee Functions and Osteoarthritis after Anterior Cruciate Ligament Reconstruction: A Narrative Review

Anterior cruciate ligament reconstruction (ACLR) is the standard surgical treatment for ACL injury, which typically uses a graft to replace the torn ligament in the knee that uses small incisions with minimally invasive surgery. The optimal knee functions following ACLR depend on rehabilitation processes before and after the surgery. Knee function is the ability of the knee to perform various types of functional movements like walking, squatting, running, jumping, and pivoting where patients expect to achieve maximum knee function or at least more than 80% of its initial condition before the injury to avoid being categorized as poor knee function after ACLR. Patients use patient-reported outcome measures to collect data on their health status and quality of life after ACLR. Post-traumatic osteoarthritis (PTOA) is a type of OA that manifests in local cartilage injury caused by chondrocyte death, and matrix dispersion occurs following a joint injury like ACL injury. Gender, time from injury to surgery, and graft type were considered as risk factors for poor knee function after ACLR, while overweight, meniscus tear, and cartilage defect as risk factors for PTOA. However, age is an internal risk factor for both poor knee function and PTOA following ACLR. This review suggests several strategies to prevent both conditions, including a pre-operative program, comprehensive rehabilitation, body weight control, and return to sport (RTS) consideration based on physical capacity, proper time, and psychological readiness.

Prevalence of post-traumatic osteoarthritis after anterior cruciate ligament injury remains high despite advances in surgical techniques

Aims

The aim of this study was to report the pooled prevalence of post-traumatic osteoarthritis (PTOA) and examine whether the risk of developing PTOA after anterior cruciate ligament (ACL) injury has decreased in recent decades.

Methods

The PubMed and Web of Science databases were searched from 1 January 1980 to 11 May 2022. Patient series, observational studies, and clinical trials having reported the prevalence of radiologically confirmed PTOA after ACL injury, with at least a ten-year follow-up, were included. All studies were analyzed simultaneously, and separate analyses of the operative and nonoperative knees were performed. The prevalence of PTOA was calculated separately for each study, and pooled prevalence was reported with 95% confidence intervals (CIs) using either a fixed or random effects model. To examine the effect of the year of injury on the prevalence, a logit transformed meta-regression analysis was used with a maximum-likelihood estimator. Results from meta-regression analyses were reported with the unstandardized coefficient (β).

Results

The pooled prevalence of PTOA was 37.9% (95% CI 32.1 to 44) for operatively treated ACL injuries with a median follow-up of 14.6 years (interquartile range (IQR) 10.6 to 16.7). For nonoperatively treated ACL injuries, the prevalence was 40.5% (95% CI 28.9 to 53.3), with a median of follow-up of 15 years (IQR 11.7 to 20.0). The association between the year of operation and the prevalence of PTOA was weak and imprecise and not related to the choice of treatment (operative β -0.038 (95% CI -0.076 to 0.000) and nonoperative β -0.011 (95% CI -0.101 to 0.079)).

Conclusion

The initial injury, irrespective of management, has, by the balance of probability, resulted in PTOA within 20 years. In addition, the prevalence of PTOA has only slightly decreased during past decades. Therefore, further research is warranted to develop strategies to prevent the development of PTOA after ACL injuries.

Influence of periostin on the development of fibrocartilage layers of anterior cruciate ligament insertion

BACKGROUND

Periostin (Postn) is thought to play a role in the formation of anterior cruciate ligament (ACL) insertion. However, the influence of Postn on the development of ACL insertion requires further understanding. This study aimed to clarify the influence of Postn on the development of fibrocartilage layers of ACL insertion.

HYPOTHESIS

We hypothesized that Postn would influence the development of fibrocartilage layers of ACL insertion.

MATERIALS AND METHODS

C57BL/6N wild-type (Postn+/+; n=54) and Postn knockout (Postn-/-; n=54) mice were used in this study. Six animals were euthanized at 1 d and 1, 2, 3, 4, 6, 8, 10, and 12 weeks of age in each group. The chondrocyte number, proliferation, apoptosis, safranin O-stained glycosaminoglycan (GAG) area, type II collagen staining area, tidemark length, and insertion width were evaluated.

RESULTS

Chondrocyte proliferation was high up to 2 weeks in Postn+/+, while low at age 1 d; it was, especially lower in Postn-/- than in Postn+/+ at age 1 d and 1 week. Chondrocyte apoptosis was high up to age 8 weeks in Postn+/+ and at 6 weeks in Postn-/-; it was especially higher in Postn-/- than in Postn+/+ at age 1 week. The GAG stained area was thickest for age 1 d to 4 weeks in Postn+/+ and for age 2 to 6 weeks in Postn-/-. The type II collagen staining area in Postn+/+ was thicker than that in Postn-/- at age 6 and 8 weeks. The tidemark length in Postn+/+ was longer than that in Postn-/- from age 8 to 12 weeks. The insertion width in Postn+/+ was longer than that in Postn-/- from age 1 to 3 weeks.

DISCUSSION

Postn decreased cell proliferation in the early postnatal phase and influenced the development of the fibrocartilage layer extracellular matrix of ACL insertion in mice. Postn may contribute to the development of methods for regeneration of the ACL insertion.

LEVEL OF EVIDENCE

V; controlled laboratory study.

The Effects of an Osteoarthritic Joint Environment on ACL Damage and Degeneration: A Yucatan Miniature Pig Model

Posttraumatic osteoarthritis (PTOA) arises secondary to joint injuries and is characteristically driven by inflammatory mediators. PTOA is often studied in the setting of ACL tears. However, a wide range of other injuries also lead to PTOA pathogenesis. The purpose of this study was to characterize the morphological changes in the uninjured ACL in a PTOA inflammatory environment. We retrospectively reviewed 14 ACLs from 13 Yucatan minipigs, 7 of which had undergone our modified intra-articular drilling (mIAD) procedure, which induced PTOA through inflammatory mediators. Seven ACLs were harvested from mIAD minipigs (PTOA) and seven ACLs from control minipigs with no cartilage degeneration (non-PTOA). ACL degeneration was evaluated using histological scoring systems. IL-1β, NF-κB, and TNF-α mRNA expression in the synovium was measured using qRT-PCR. PTOA minipigs demonstrated significant ACL degeneration, marked by a disorganized extracellular matrix, increased vascularity, and changes in cellular shape, density, and alignment. Furthermore, IL-1β, NF-κB, and TNF-α expression was elevated in the synovium of PTOA minipigs. These findings demonstrate the potential for ACL degeneration in a PTOA environment and emphasize the need for anti-inflammatory disease-modifying therapies following joint injury.

Long-term Quality of Life in Patients After ACL Reconstruction With Concomitant Meniscal Injury Treatment: Patient-Reported Outcomes at Minimum 10-Year Follow-up

Background

Long-term studies of patients after anterior cruciate ligament (ACL) reconstruction with or without concomitant meniscal tear treatment are limited.

Purposes

To (1) report postoperative outcomes after anatomic ACL reconstruction with a hamstring autograft, (2) investigate how concomitant treatment of meniscal injury could affect these outcomes, and (3) evaluate the association between quality of life and activity levels at a minimum 10-year follow-up.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients treated with a unilateral, anatomic ACL reconstruction between 2005 and 2011 were investigated. The following patient-reported outcome measures (PROMs) were reported for the overall sample as well as a subsample of patients with meniscal injury: International Knee Documentation Committee Subjective Knee Form (IKDC-SKF), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm knee score, Tegner activity scale, 5-level EQ-5D (EQ-5D-5L), and patient satisfaction. Sex, age, body mass index (BMI), and meniscal injury treatment (meniscectomy vs meniscal repair) were examined as patient-specific risk factors regarding long-term activity and quality of life.

Results

Overall, 106 patients, 90 men (85%) and 16 women (15%), were enrolled in the study, with a mean follow-up of 13.2 years. The ACL retear rate was 2.8%. The mean scores were 80.6 ± 16.7 (IKDC-SKF), 87.4 ± 15.0 (KOOS), 90.5 ± 11.5 (Lysholm), 5.6 ± 1.9 (Tegner), and 91.8 ± 14.5 (EQ-5D-5L). The majority (90.6%) of patients considered their knee state satisfactory during follow-up. When compared with patients who underwent meniscal repair, patients who underwent meniscectomy had statistically significantly lower scores on all PROMs except for the Tegner and EQ-5D-5L (P < .05 for all). The mean difference between the 2 groups was ≥7 points on all PROM scores. Patient sex, age, and BMI did not affect PROM scores. There was a statistically significant, strong positive correlation between quality of life and activity.

Conclusion

Patients had few or no symptoms and considered their knee state satisfactory 13.2 years after anatomic ACL reconstruction. Patients with concomitant meniscal tears having undergone meniscal repair had improved PROMs compared with those treated with meniscectomy. Finally, participation in activities of daily living and sports was interrelated with quality of life and was not affected by patient age, sex, or BMI.

Radiographic Incidence of Knee Osteoarthritis After Isolated ACL Reconstruction Versus Combined ACL and ALL Reconstruction: A Prospective Matched Study From the SANTI Study Group

BACKGROUND

Combined anterior cruciate ligament (ACL) reconstruction (ACLR) and anterolateral ligament reconstruction (ALLR) have demonstrated reduced risk of graft rerupture as compared with isolated ACLR. However, concerns remain that the risk of osteoarthritis (OA) may be increased by the addition of ALLR.

PURPOSE/HYPOTHESIS

The aim of this study was to evaluate the incidence of OA with isolated ACLR in comparison with ACLR + ALLR at medium-term follow-up. We hypothesized that there would be no differences between the groups.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent ACLR + ALLR with hamstring tendon autograft between January 2011 and March 2012 were propensity matched to patients who underwent isolated ACLR with bone-patellar tendon-bone (BPTB) or hamstring tendon autograft in the same period. Medium-term radiographic evaluation was performed using the International Knee Documentation Committee (IKDC) radiographic OA grading scale, modified Kellgren-Lawrence grade, and the surface fit method to assess percentage of joint space narrowing. Clinical outcomes were assessed with the following measures: IKDC, Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm, Tegner, and ACL Return to Sport after Injury.

RESULTS

A total of 80 patients (42 ACLR + ALLR and 38 isolated ACLR) were analyzed with a mean follow-up of 104 months. There was no significant difference between groups for joint space narrowing in the medial or lateral tibiofemoral or lateral patellofemoral (PF) compartment. However, 36.8% in the isolated ACLR group versus 11.9% in the ACLR + ALLR group had narrowing of the medial PF compartment (P = .0118). A lateral meniscal tear increased the risk of lateral tibiofemoral narrowing by nearly 5 times (odds ratio, 4.9; 95% CI, 1.547-19.367; P = .0123). The risk of medial PF narrowing was >4-fold with an isolated ACLR (odds ratio, 4.8; 95% CI, 1.44-19.05; P = .0179). Between the isolated ACLR group and the ACLR + ALLR group, the secondary meniscectomy rate was 13.2% versus 11.9% (not significantly different). There was no difference between groups in KOOS, Tegner, or IKDC scores. There was also no difference between groups for grades of osteoarthritic change for any classification system. Patients who received a BPTB graft had medial PF joint narrowing in 66.7% of cases as compared with 11.9% in those who received ACLR + ALLR (P = 0.118).

CONCLUSION

ACLR + ALLR did not increase the risk of OA in the lateral tibiofemoral compartment when compared with an isolated ACLR at medium-term follow-up. Isolated ACLR using BPTB was associated with a significantly increased risk of medial PF joint space narrowing.

REGISTRATION

NCT05123456 (ClinicalTrials.gov identifier).

Reliability of Continuous Shear Wave Elastography in the Pathological Patellar Tendon

OBJECTIVES

Patellar tendon injuries occur via various mechanisms such as overuse, or due to surgical graft harvest for anterior cruciate ligament reconstruction (ACLR). Quantified patellar tendon stiffness after injury may help guide clinical care. Continuous shear wave elastography (cSWE) allows for the assessment of viscosity and shear modulus in tendons. The reliability of the measure, however, has not been established in the patellar tendon. The purpose of this study was to investigate the interrater reliability, intrarater reliability, and between-day stability of cSWE in both healthy and pathological patellar tendons.

METHODS

Participants with patellar tendinopathy (n = 13), history of ACLR using bone-patellar tendon-bone autograft (n = 9), and with no history of patellar tendon injury (n = 13) were recruited. cSWE was performed 4 times by multiple raters over 2 days. Intraclass correlations (ICC) and minimum detectable change (MDC_95% ) were calculated.

RESULTS

Good to excellent between-day stability were found for viscosity (ICC = 0.905, MDC_95%  = 8.3 Pa seconds) and shear modulus (ICC = 0.805, MDC_95%  = 27.4 kPa). The interrater reliability measures, however, were not as reliable (ICC = 0.591 and 0.532).

CONCLUSIONS

cSWE is a reliable assessment tool for quantifying patellar tendon viscoelastic properties over time. It is recommended, however, that a single rater performs the measure as the interrater reliability was less than ideal.

The effects of the amount of weight bearing on articular cartilage early after ACL reconstruction in rats

PURPOSE

Osteoarthritis that develops after anterior cruciate ligament (ACL) reconstruction is a critical issue. We examined the effects of the amount of weight bearing early after ACL reconstruction on articular cartilage.

MATERIALS AND METHODS

Rats were divided into groups according to the treatment received: untreated control, ACL reconstruction (ACLR), ACL reconstruction plus hindlimb unloading (ACLR + HU), and ACL reconstruction plus morphine administration (ACLR + M). ACL reconstruction was performed on the right knee throughout the groups. To assess the amount of weight bearing, one-hindlimb standing time ratio (STR; operated side/contralateral side) during treadmill locomotion was evaluated during the experimental period. At day 7 or 14 post-surgery, cartilage degeneration of the medial tibial plateau was histologically assessed.

RESULTS

In the ACLR group, reduction in weight bearing characterized by significantly reduced STR was observed between day 1 and 7. Reduction in weight bearing was partially attenuated by morphine administration. Compared with the control group, the ACLR group exhibited an increased Mankin score that was accompanied by increased cyclooxygenase-2 expression in the anterior region. In the ACLR + HU group, Mankin scores were significantly higher in the middle and posterior regions, and cartilage thickness in these regions was significantly thinner than those in the ACLR group. In the ACLR + M group, although chondrocyte density in the anterior region was increased, all other parameters were not significantly different from those in the ACLR group.

CONCLUSIONS

Our results suggest that early weight bearing after ACL reconstruction is important to reduce cartilage degeneration.

Is Preferred Language Other Than English Associated With Delayed Surgery After ACL Injury in Children and Adolescents?

BACKGROUND

Previous studies have investigated the impact of social determinants of health, such as the type of healthcare insurance and household income, on children and adolescents with ACL tears. However, despite the increasing incidence of ACL injury in young patients and a substantial proportion of families who may prefer languages other than English, the relationship between language and clinical care remains unclear.

QUESTIONS/PURPOSES

To investigate the relationship between language and the care of children and adolescents with ACL tears, we asked: (1) Is a preferred language other than English (PLOE) associated with a delay between ACL injury and surgery? (2) Is a PLOE associated with a greater odds of a patient experiencing a meniscal tear and undergoing a meniscectomy than in those who prefer English?

METHODS

We treated 591 patients surgically for ACL injuries between 2011 and 2021. Of those, we considered patients aged 18 years or younger who underwent primary ACL reconstruction for this retrospective, comparative study. Five percent (31 of 591) of patients were excluded because the date of injury was not clearly documented, 2% (11 of 591) were revision reconstructions, and 1% (6 of 591) underwent procedures that were intentionally delayed or staged, leaving 92% (543 of 591) for analysis. The mean age was 16 ± 2 years, and 51% (276 of 543) of patients were boys. The family's preferred language was noted, as were demographic data, time between injury and surgery, and intraoperative findings. A language other than English was preferred by 21% (113 of 543) of patients. Of these, 94% (106 of 113) preferred Spanish. In a univariate analysis, we used independent-samples t-tests, Mann-Whitney U-tests, and Fisher exact tests, as appropriate. Purposeful-entry multivariable regression analyses were used to determine whether PLOE was associated with increased time to surgery, concomitant meniscus injury, or performance of meniscectomy while adjusting for confounding variables. Variables were included in multivariable models if they met the threshold for statistical significance in univariate testing (p < 0.05).

RESULTS

The median time between injury and ACL reconstruction was shorter in families who preferred English compared with those with a PLOE (69 days [IQR 80] versus 103 days [IQR 107)]; p < 0.001). After controlling for potentially confounding variables like insurance and age, we found that patients whose families had a PLOE had greater odds of undergoing surgery more than 60 days after injury (OR 2.2 [95% CI 1.3 to 3.8]; p = 0.005) and more than 90 days after injury (OR 1.8 [95% CI 1.1 to 2.8]; p = 0.02). After controlling for insurance, age, and other factors, PLOE was not associated with surgical delay beyond 180 days, concomitant meniscal tears, or performance of meniscectomy.

CONCLUSION

In this study of children and adolescents undergoing primary ACL reconstruction, patients whose families prefer a language other than English experienced a longer delay between injury and surgery. In areas with a large proportion of families with a PLOE, partnerships with primary care clinicians, emergency departments, schools, athletic teams, and community organizations may improve efficiency in the care of children with ACL injuries. Clinicians proficient in other languages, reliable interpreter services, and translated references and resources may also be impactful. Our results suggest a need for further research on the experiences, needs, and long-term outcomes of these patients, as well as the association of preferred language with results after surgery.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The anterior cruciate ligament injury severity scale (ACLISS) is an effective tool to document and categorize the magnitude of associated tissue damage in knees after primary ACL injury and reconstruction

PURPOSE

To develop a tool allowing to classify the magnitude of structural tissue damage occurring in ACL injured knees. The proposed ACL Injury Severity Scale (ACLISS) would provide an easy description and categorization of the wide spectrum of injuries in patients undergoing primary ACL reconstruction, reaching from isolated ACL tears to ACL injuries with a complex association of combined structural damage.

METHODS

A stepwise approach was used to develop the ACLISS. The eligibility of each item was based on a literature search and a consensus between the authors after considering the diagnostic modalities and clinical importance of associated injuries to the menisci, subchondral bone, articular cartilage or collateral ligaments. Then, a retrospective analysis of associated injuries was performed in 100 patients who underwent a primary ACL reconstruction (ACLR) by a single surgeon. This was based on acute preoperative MRI (within 8 weeks after injury) as well as intraoperative arthroscopic findings. Depending on their prevalence, the number of selected items was reduced. Finally, an analysis of the overall scale distribution was performed to classify the patients according to different injury profiles.

RESULTS

A final scoring system of 12 points was developed (12 = highest severity). Six points were attributed to the medial and lateral tibiofemoral compartment respectively. The amount of associated injuries increased with ACLISS grading. The median scale value was 4.5 (lower quartile 3.0; higher quartile 7.0). Based on these quartiles, a score < 4 was considered to be an injury of mild severity (grade I), a score between ≥ 4 and ≤ 7 was defined as moderately severe (grade II) and a score > 7 displayed the most severe cases of ACL injuries (grade III). The knees were graded ACLISS I in 35%, ACLISS II in 49% and ACLISS III in 16% of patients. Overall, damage to the lateral tibiofemoral compartment was predominant (p < 0.01), but a proportional increase of tissue damage could be observed in the medial tibiofemoral compartment with the severity of ACLISS grading (p < 0.01).

CONCLUSIONS

The ACLISS allowed to easily and rapidly identify different injury severity profiles in patients who underwent primary ACLR. Injury severity was associated with an increased involvement of the medial tibiofemoral compartment. The ACLISS is convenient to use in daily clinical practice and represents a feasible grading and documentation tool for a reproducible comparison of clinical data in ACL injured patients.

LEVEL OF EVIDENCE

Level III.

Risk factors for knee osteoarthritis after traumatic knee injury: a systematic review and meta-analysis of randomised controlled trials and cohort studies for the OPTIKNEE Consensus

OBJECTIVE

To identify and quantify potential risk factors for osteoarthritis (OA) following traumatic knee injury.

DESIGN

Systematic review and meta-analyses that estimated the odds of OA for individual risk factors assessed in more than four studies using random-effects models. Remaining risk factors underwent semiquantitative synthesis. The modified GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach for prognostic factors guided the assessment.

DATA SOURCES

MEDLINE, EMBASE, CENTRAL, SPORTDiscus, CINAHL searched from inception to 2009-2021.

ELIGIBILITY

Randomised controlled trials and cohort studies assessing risk factors for symptomatic or structural OA in persons with a traumatic knee injury, mean injury age ≤30 years and minimum 2-year follow-up.

RESULTS

Across 66 included studies, 81 unique potential risk factors were identified. High risk of bias due to attrition or confounding was present in 64% and 49% of studies, respectively. Ten risk factors for structural OA underwent meta-analysis (sex, rehabilitation for anterior cruciate ligament (ACL) tear, ACL reconstruction (ACLR), ACLR age, ACLR body mass index, ACLR graft source, ACLR graft augmentation, ACLR+cartilage injury, ACLR+partial meniscectomy, ACLR+total medial meniscectomy). Very-low certainty evidence suggests increased odds of structural OA related to ACLR+cartilage injury (OR=2.31; 95% CI 1.35 to 3.94), ACLR+partial meniscectomy (OR=1.87; 1.45 to 2.42) and ACLR+total medial meniscectomy (OR=3.14; 2.20 to 4.48). Semiquantitative syntheses identified moderate-certainty evidence that cruciate ligament, collateral ligament, meniscal, chondral, patellar/tibiofemoral dislocation, fracture and multistructure injuries increase the odds of symptomatic OA.

CONCLUSION

Moderate-certainty evidence suggests that various single and multistructure knee injuries (beyond ACL tears) increase the odds of symptomatic OA. Risk factor heterogeneity, high risk of bias, and inconsistency in risk factors and OA definition make identifying treatment targets for preventing post-traumatic knee OA challenging.

Consensus statement on data to be entered in the ACL tear registry: SFA-DataLake

INTRODUCTION

Anterior cruciate ligament (ACL) reconstruction is a frequent procedure, with room for improvement by rehabilitation measures and associated peripheral and meniscal surgeries that are currently under assessment, requiring follow-up. Outside France, there have been ACL registries for 20 years now. The French Arthroscopy Society (SFA) decided to set up an ACL tear registry within its SFA DataLake registry platform.

MATERIAL AND METHOD

This article presents the methodology underlying the ACL Tear Registry: i.e., identification, definition and coding of essential and relevant data. A test phase comprised an initial assessment to improve data quality and overall coherence, to optimize data-entry time for patients and practitioners, who are the guarantors of the registry's use and efficacy.

RESULTS

The SFA DataLake ACL Tear Registry was made available to SFA members in December 2021. It aims to enable a review of practices for surgeons, early detection of failure of procedures and implants, with rates of failure and abnormal complications, and identification of prognostic factors for outcome, especially regarding original items that do not figure in previous registries.

CONCLUSION

SFA DataLake strikes a balance between "indispensable" and "original" items. The choice of contents and data quality is founded on a robust methodology with overall coherence, enabling analysis of large cohorts and comparisons with the literature and other registries. However, it remains to assess rates of data entry and item relevance as the Registry progresses.

LEVEL OF EVIDENCE

IV.

Relationship between histological changes of the anterior cruciate ligament and knee function in osteoarthritis patients

BACKGROUND

The function of the anterior cruciate ligament (ACL) in osteoarthritis (OA) of the knee remains to be elucidated. The purpose of this study is to evaluate histological changes of the ACL in end-stage knee OA and to clarify the relationship between histological changes in the ACL and knee function.

HYPOTHESIS

The hypothesis in this study was that ACL degeneration in knee OA is associated with decreased knee function.

PATIENTS AND METHODS

Eighty-two ACL specimens from 65 patients who underwent primary total knee arthroplasty (TKA) were investigated. The correlation between histological changes of the ACL (myxoid changes, chondroid metaplasia, total collagen degeneration, microcyst formation, vascular proliferation, and inflammatory cell infiltration) and knee function (range of motion, anterior tibial translation test, knee extension muscle strength, one-leg standing time, and functional reach test) were investigated. Age, body mass index, joint space narrowing, osteophyte formation, lower extremity alignment, and knee medial/lateral instability were also evaluated.

RESULTS

Myxoid change in the ACLs was significantly negatively correlated with one-leg standing time. Chondroid metaplasia was not correlated with knee function. Collagen degeneration in the ACL was significantly negatively correlated with knee flexion angle and one-leg standing time. In addition, a negative correlation between microcyst formation and knee flexion angle was noted. Osteophyte formation, particularly lateral femoral intercondylar osteophytes, was correlated with myxoid changes. The other parameters did not correlate with ACL histological changes.

DISCUSSION

Myxoid changes in the ACL were shown to correlate with knee function. The osteophyte score, particularly as related to lateral femoral intercondylar osteophytes, correlated with the severity of myxoid changes in the ACL in knee OA. Precise ACL evaluation should be included in the indications for ACL-retaining surgeries because ACL degeneration may be related to decreased knee function after surgery.

LEVEL OF EVIDENCE

IV, Diagnostic case series.

The SFA datalake platform and anterior cruciate ligament tear registry of the French Society of Arthroscopy (SFA): Rationale, statutes and plans

SFA Datalake is the registry platform of the French Society of Arthroscopy (SFA). It was designed to collect and store data on arthroscopic orthopedic surgery and joint-sparing surgery in French-speaking countries. The anterior cruciate ligament (ACL) tear registry is the first registry to be set up based on SFA Datalake. Registries are intended to enable systematic standardized data collection, and provide information for surgeons to improve clinical practice and results. The ACL tear registry was designed in the light of guidelines, the literature and existing registries. Data are collected prospectively on a secure on-line application accessible via a computer or smartphone. Data collection is organized according to clinical examination results, preoperative findings, and follow-up data based on patient-administered subjective quality of life questionnaires. The pilot committee consists of 5 SFA board members, appointed for 2 years. LEVEL OF EVIDENCE: IV.

Environmental Risk Factors for Osteoarthritis: The Impact on Individuals with Knee Joint Injury

Osteoarthritis is a debilitating chronic condition involving joint degeneration, impacting over 300 million people worldwide. This places a high social and economic burden on society. The knee is the most common joint impacted by osteoarthritis. A common cause of osteoarthritis is traumatic joint injury, specifically injury to the anterior cruciate ligament. The purpose of this review is to detail the non-modifiable and modifiable risk factors for osteoarthritis with particular focus on individuals after anterior cruciate ligament injury. After reading this, health care providers will better comprehend the wide variety of factors linked to osteoarthritis.

Effects of Initial Graft Tension and Patient Sex on Knee Osteoarthritis Outcomes After ACL Reconstruction: A Randomized Controlled Clinical Trial With 10- to 12-Year Follow-up

BACKGROUND

The initial graft tension applied during anterior cruciate ligament (ACL) graft fixation may promote posttraumatic osteoarthritis (PTOA).

PURPOSE/HYPOTHESIS

This study sought to assess the effect of initial graft tension and patient sex on PTOA outcomes at 10 to 12 years after ACL reconstruction (ACLR). The hypothesis was that there would be no group- or sex-based differences in outcomes.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients were randomized to receive ACLR with a low or high initial graft tension. Outcomes were evaluated at 10 to 12 years postoperatively and compared with a matched, uninjured control group. Outcomes included clinical assessments (anteroposterior [AP] knee laxity measurement, International Knee Documentation Committee [IKDC] examination score), a functional assessment (single-leg hop for distance), patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score [KOOS], 36-Item Short Form Health Survey, Tegner activity level, patient satisfaction), and PTOA imaging (Osteoarthritis Research Society International [OARSI] radiographic score and Whole-Organ Magnetic Resonance Imaging Score [WORMS]). Two-way mixed-model analyses of variance were used to evaluate differences in outcomes between tension groups and the control group and between female and male patients.

RESULTS

Both tension groups scored worse than the control group for the IKDC examination (P≤ .021), KOOS (Pain, Activities of Daily Living, Sport/Recreation, and Quality of Life subscales) (P≤ .049), and WORMS difference score (P≤ .042). The low-tension group scored worse than the control group for KOOS Symptoms (P = .016) and the OARSI difference score (P = .015). The index limb had worse scores than the contralateral limb within the high-tension group for AP laxity (P = .030) and hop deficit (P = .011). This result was also observed within both tension groups for the WORMS (P≤ .050) and within the low-tension group for the OARSI score (P = .001). Male patients had higher Tegner scores (mean ± SE) relative to female patients (male, 5.49 ± 1.88; female, 4.45 ± 1.65) and worse OARSI difference scores (male, 1.89 ± 5.38; female, 0.244 ± 0.668) (P = .007 and .034, respectively). However, no significant differences were detected between tension groups for any of the outcomes measured.

CONCLUSION

Overall, ACLR failed to prevent PTOA regardless of initial graft tension. However, male patients treated with a low initial graft tension may be at greater risk for PTOA. These results do not support the hypothesis of no sex differences in outcomes at 10 to 12 years after ACLR.

Effects of Joint Immobilization and Treadmill Exercise on Articular Cartilage After ACL Reconstruction in Rats

Background:

The development of osteoarthritis after anterior cruciate ligament (ACL) reconstruction (ACLR) is an important issue. However, the appropriate rehabilitation protocol to prevent cartilage degeneration due to postoperative osteoarthritis is unclear.

Purpose:

To examine the effects of joint immobilization and treadmill exercise on articular cartilage after ACLR.

Study Design:

Controlled laboratory study.

Methods:

A total of 55 rats received unilateral knee ACL transection and reconstruction surgery using tail tendon autografts. After surgery, rats were reared without intervention, with joint immobilization, or with daily treadmill exercise (12 m/minute, 60 minutes/day, 6 days/week). Treadmill exercise was initiated at 3 or 14 days postoperatively. After 2 weeks of immobilization, the fixation device was removed from some of the immobilized rats, and the knee was allowed to move freely for 2 weeks. Untreated, age-matched rats (n = 8) were used as controls. At 2 or 4 weeks after starting the experiment, cartilage degeneration in the medial tibial plateau was histologically assessed using a modified Mankin score, cartilage thickness, chondrocyte density, and immunohistochemistry for cyclooxygenase-2 (COX-2) in the anterior, middle, and posterior regions.

Results:

After ACLR, cartilage degeneration in the anterior region characterized by increased Mankin score, accompanied with increased COX-2 expression, was detected. Joint immobilization after ACLR facilitated cartilage degeneration, which is detected by histological changes such as reductions in cartilage thickness, chondrocyte density, and high Mankin scores. Enhanced COX-2 expression in all degenerated cartilage regions was also detected. It was found that 2 weeks of remobilization could not restore cartilage degeneration induced by 2 weeks of immobilization after ACLR. Treadmill exercise after ACLR did not affect most articular cartilage parameters, regardless of the timing of exercise.

Conclusion:

Our results indicated that (1) immobilization after ACLR accelerates cartilage degeneration, even when applied only for 2 weeks, and (2) mild exercise during early phases after ACLR does not facilitate cartilage degeneration.

Clinical Relevance:

To reduce cartilage degeneration, periods of joint immobilization after ACLR should be minimized. Mild exercise during the early phases after ACLR will not negatively affect articular cartilage.

A high level of knee laxity after anterior cruciate ligament reconstruction results in high revision rates

PURPOSE

The literature indicates a lack of consensus on the correlation between knee laxity after anterior cruciate ligament reconstruction (ACLR) and subjective clinical outcomes and the need for revision surgery. Therefore, using high-volume registry data, this study aimed to describe the relationship between objective knee laxity after ACLR and subjective symptom and functional assessments and the need for revision surgery. The hypothesis was that greater postoperative knee laxity would correlate with inferior patient-reported outcomes and a higher risk for revision surgery.

METHODS

In this study, 17,114 patients in the Danish knee ligament reconstruction registry were placed into three groups on the basis of objective side-to-side differences in sagittal laxity one year after surgery: group A (≤ 2 mm), Group B (3-5 mm) and Group C (> 5 mm). The main outcome measure was revision rate within 2 years of primary surgery, further outcome measures were the knee injury and osteoarthritis outcome score (KOOS) as well as Tegner activity score.

RESULTS

The study found the risk for revision surgery was more than five times higher for Group C [hazard ratio (HR) = 5.51] than for Group A. The KOOS knee-related Quality of Life (QoL) sub-score exhibited lower values when comparing Groups B or C to Group A. In addition, the KOOS Function in Sport and Recreation (Sport/Rec) sub-score yielded lower values for groups B and C in comparison with Group A.

CONCLUSION

These results indicate that increased post-operative sagittal laxity is correlated with an increased risk for revision surgery and might correlate with poorer knee-related QoL, as well as a decreased function in sports. The clinical relevance of the present study is that high knee laxity at 1-year follow-up is a predictor of the risk of revision surgery.

LEVEL OF EVIDENCE

III.

The coronal lateral collateral ligament sign in the anterior cruciate ligament-injured knees was observed regardless of the knee laxity based on the quantitative measurements

PURPOSE

The coronal lateral collateral ligament (LCL) sign has been reported to be associated with deviated position of the tibia on MRI due to anterior cruciate ligament (ACL) injuries. However, the relationships between LCL sign and clinical knee laxity evaluations are still unclear. The purpose of the study was to investigate the relationship between the coronal LCL sign and knee laxity measurements.

METHODS

A retrospective review of unilateral ACL injured patients who underwent ACL reconstruction was performed. The coronal LCL sign was determined using magnetic resonance imaging (MRI). Clinical grading of the pivot-shift test, KT-1000 measurements, and quantitative measurements of the Lachman test and the pivot-shift test using an electromagnetic system, were compared between patients with positive and negative coronal LCL sign. A subgroup analysis of different age groups was then performed, dividing patients to adolescent (age ≤ 18 years) and adult (age > 18 years) groups.

RESULTS

A total of 85 patients were enrolled, of which 45 patients had coronal LCL signs. The coronal LCL sign was not associated with the pivot-shift test clinical grading (n.s), KT-1000 measurement (n.s), the tibial translation during the Lachman test (n.s), or with tibia acceleration (n.s) and translation (n.s) during the pivot-shift test. The subgroup analysis also showed that the aforementioned parameters were not associated with the coronal LCL sign in either adolescent or adult subgroups.

CONCLUSION

The occurrence of coronal LCL sign in MRI did not imply greater clinical knee laxity evaluations in patients with ACL tears. The knee laxity should routinely be evaluated regardless the coronal LCL sign.

LEVEL OF EVIDENCE

Level III.

Risk factors of cartilage lesion after anterior cruciate ligament reconstruction

Anterior cruciate ligament injury is the most common sports injury in orthopaedics, which can adversely affect knee joint function and exercise of patients. Using arthroscopy to reconstruct the anterior cruciate ligament has become the first choice for treating anterior cruciate ligament rupture. However, different degrees of articular cartilage injury of the knee can be observed in patients after anterior cruciate ligament reconstruction. More importantly, the articular cartilage injury after anterior cruciate ligament reconstruction indicates that it will develop into osteoarthritis in the long term. It is of great significance to fully understand the factors that lead to the occurrence and development of cartilage injury. This article reviews the effects of surgical methods, meniscus status, different grafts, time from injury to surgical intervention, postoperative knee joint stability, postoperative rehabilitation, knee joint anatomical factors, and demographic characteristics of patients on articular cartilage degeneration after anterior cruciate ligament reconstruction. The present review provides insights into the anterior cruciate ligament reconstruction, which can be used to investigate new treatment strategies to delay and prevent the progress of osteoarthritis. At the same time, it provides a holistic understanding of the influence of multiple factors on cartilage lesions after anterior cruciate ligament reconstruction.

Comparison of Rotatory and Sagittal Laxity After Single-Bundle Versus Double-Bundle ACL Reconstruction: Outcomes at 7-Year Follow-up

Background:

Biomechanical studies have shown excellent anteroposterior and rotatory laxity control after double-bundle (DB) anterior cruciate ligament (ACL) reconstruction, but no clinical studies have compared midterm (>5-year) residual laxity between the DB and single-bundle (SB) techniques.

Purpose:

To clinically compare sagittal and rotatory laxities and residual sagittal laxity on the KT-1000 arthrometer between patients treated with an SB ACL reconstruction and those treated with a DB ACL reconstruction at the 7-year follow-up.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 110 patients were included between January 2006 and December 2007. The patients were randomly assigned into 2 groups: those treated with SB ACL reconstruction (n = 63) and those treated with the DB technique (n = 47). All patients were then reviewed at a minimum of 7 years of follow-up; patients with ACL rerupture (n = 3 in the SB group and n = 2 in the DB group) were excluded from the postoperative comparative analysis. Residual anterior laxity (Lachman test), rotatory laxity (pivot-shift test), and sagittal laxity (KT-1000 arthrometer side-to-side difference) were measured and compared between the 2 groups.

Results:

The mean age at surgery was 23.0 ± 5.1 years for the DB group and 28.1 ± 7.0 years for the SB group, and the mean follow-up was 7.4 ± 0.8 years. No statistically significant differences were found between the 2 groups in terms of age, sex, preoperative laxity on KT-1000, preoperative Tegner score, or concomitant meniscal lesions. Residual postoperative laxity via Lachman testing (P < .01), pivot-shift testing (P = .042), and the KT-1000 arthrometer (P < .01) was statistically significantly in favor of DB reconstruction.

Conclusion:

DB ACL reconstruction allowed better control of anterior stability during the evaluation via the Lachman test and via objective measurement on the KT-1000, as well as rotatory stability at a minimum of 7 years of follow-up.

Identifying Gait Pathology after ACL Reconstruction Using Temporal Characteristics of Kinetics and Electromyography

PURPOSE

Asymmetrical gait mechanics after anterior cruciate ligament reconstruction (ACLR) are associated with the development of posttraumatic knee osteoarthritis. Current measures of gait mechanics have focused heavily on peak magnitudes of knee kinematics, kinetics, and joint contact forces but have seldom considered the rate of knee loading, cumulative knee load, or the timing of motor input surrounding peaks. The purpose of this study was to introduce and describe novel metrics of gait using temporal characteristics of kinetics and EMG to identify neuromuscular deficits of the quadriceps in patients after ACLR.

METHODS

Gait mechanics were assessed 6 months (n = 145) and 24 months (n = 116) after ACLR. External knee flexion rate of moment development (RMD) and knee flexion moment impulse (KFMI) leading up to the time of peak knee flexion moment (pKFM), peak RMD between initial contact to pKFM, and cumulative KFMI were calculated. Extensor latencies from the quadriceps, vastus medialis, vastus lateralis, and rectus femoris (time of pKFM - time of peak EMG activity) during the weight acceptance phase of gait were also calculated. Paired-sample t-tests (α = 0.05) were performed between limbs at both time points.

RESULTS

Slower RMD, smaller KFMI, and longer extensor latencies in the involved compared with uninvolved limb were observed across all measures at 6 months (P < 0.005). At 24 months, RMDpeak was slower, and KFMI50ms, KFMI100ms, and KFMItotal were lower in the involved limb (P < 0.003), but no other asymmetries were found.

CONCLUSIONS

Slower RMD, smaller KFMI, and prolonged extensor latencies may characterize neuromuscular deficits underlying aberrant gait mechanics early after ACLR. RMD, KFMI, and extensor latencies during gait should be considered in the future to quantify asymmetrical movement patterns observed after ACLR and as markers of recovery.

Prevalence and Incidence of Chondral and Meniscal Lesions in Patients Undergoing Primary and Subsequent Revision Anterior Cruciate Ligament Reconstruction: An Analysis of 213 Patients From the SANTI Group

BACKGROUND

Previous studies have shown a higher prevalence of meniscal and chondral lesions at the time of revision anterior cruciate ligament reconstruction (R-ACLR) compared with primary ACLR procedures. However, studies that follow the development of meniscal and chondral status through primary and subsequent R-ACLR are scarce.

PURPOSE

To compare the prevalence of meniscal and chondral injuries in patients undergoing primary ACLR and subsequent R-ACLR.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent ACLR and subsequently needed R-ACLR between January 2009 and February 2018 in a single center were included. A retrospective analysis of prospectively collected data was conducted.

RESULTS

A total of 213 patients were included, with a mean follow-up of 59.7 months. The mean age was 22 years at primary ACLR and 26.1 years at the time of revision. The proportion of meniscal tears was higher at the time of R-ACLR compared with the time of primary reconstruction (70.0% vs 44.6%, respectively; P < .001). Similarly, the prevalence of chondral lesions was significantly higher at the time of revision versus the primary reconstruction (15.5% vs 7.0%, respectively; P = .003).

CONCLUSION

R-ACLR is associated with a higher rate of concomitant meniscal and chondral lesions than primary ACLR.

Biological enhancement methods may be a viable option for ACL arthroscopic primary repair - A systematic review

BACKGROUND

Bioactive factors combined with advanced anterior cruciate ligament (ACL) primary repair technology have been used to treat ACL repairs. The current review was conducted to identify whether biological enhancement could enable superior clinical outcome, including side-to-side difference, failure rate, reoperation rate and subjective scores.

HYPOTHESIS

The implementation of ACL primary repair with biological enhancement will provide better clinical outcomes in terms of side-to-side differences, failure rate, reoperation rate and subjective scores than ACL primary repair alone.

MATERIALS AND METHODS

A systematic literature review was performed following PRISMA guidelines by searching all studies reporting outcomes of arthroscopic primary repair with or without biological augmentation published until April 19, 2020, in Medline, PubMed, Embase and the Cochrane Library. Primary metrics were side-to-side differences, failure rate and reoperation rate, as well as measurements of patient-reported outcomes at the last follow-up.

RESULTS

A total of 20 studies were finally included in this work, of which 3 were Grade I (15%), 3 studies were Grade III (15%), and 14 studies were Grade IV (70%) in terms of the level of evidence. There were 729 patients with a mean age of 30 (range: 8-68) years, and the mean follow-up period of which was 38 (range: 3-122) months. At the final follow-up, the postoperative side-to-side differences (the proportion of patients with a side-to-side difference less than 3mm) and patient-report outcomes were significantly better in the biological enhancement group. Nevertheless, there were no significant differences between the two groups in the rate of surgical failure, the rate of revision, or the positive Lachman test or pivot shift test.

CONCLUSION

Biologically enhanced arthroscopic ACL primary repair was superior to ACL primary repair alone in terms of postoperative side-to-side differences (proportion of patients with a side-to-side difference less than 3mm) and patient-reported outcomes. Thus, biologically enhanced arthroscopic ACL primary repair can be preferentially recommended over ACL arthroscopic primary repair alone.

LEVEL OF EVIDENCE

IV, systematic review.

Surgical technique of anterior cruciate ligament ligamentoplasty with pedicular hamstrings via an inside-out approach: BIOFAST hamstring tendons graft

This surgical technique of anterior cruciate ligament (ACL) reconstruction uses a 4-stranded hamstring tendons graft (HG), via an inside-out approach with a femoral cortical button and a tibial screw. It offers preservation of the tibial attachment of the hamstrings and enables double tibial fixation: biological and mechanical. This technique, "BIOFAST HG", does not require any calculation of the length of the tunnels, nor the use of different sized, or adjustable, buttons. If the sliding in the femoral tunnel fails, it is possible to easily convert to a so-called "classic technique". The first 60 cases were reviewed with a conversion rate of 3%. This technique allows the benefits of a pedicled graft over the classic HG technique in a simple way, with minimal conversions to the classic technique.

Validity of the lever sign test for the clinical diagnosis of anterior cruciate ligament tears: Assessments in ski resorts

INTRODUCTION

The clinical diagnosis of an anterior cruciate ligament (ACL) tear is based on 3 tests: anterior drawer, pivot shift and Lachman. The latter is the most commonly used test. The "lever sign" is a new clinical test that was first described by Lelli et al. in 2014. The primary objective of this study was to determine the sensitivity of the lever sign test for the clinical diagnosis of ACL tears, in the primary care setting of patients with acute knee injuries. Primary care being the first point of contact between patients and the healthcare system (general practitioners in this study). The secondary objective was to calculate the positive predictive value (PPV) of the lever sign test, by comparing it to the PPV of the Lachman test and its sensitivity. The working hypothesis was that the sensitivity of the lever sign test was equal to or greater than 80%.

METHODS

This prospective cohort study included patients with ski-related knee injuries which occurred in French ski resorts between December 1, 2019, and March 15, 2020. The Lachman test and the lever sign test were performed by 36 mountain physicians and were compared to the magnetic resonance imaging (MRI) findings. The lever sign test involved placing a closed fist under the patient's calf in the supine position and applying downward pressure over the quadriceps. Depending on whether the ACL was intact or not, the patient's heel would either rise off the examination table or remain still. This study included 258 patients: 190 women and 68 men.

RESULTS

The MRIs found 219 ACL tears and 36 intact ACLs. Three MRIs were deemed uninterpretable. The sensitivity of the lever sign test was 61.2% and the PPV was 83.8%. The sensitivity of the Lachman test was 99.1% and the PPV was 86.5%.

CONCLUSION

This study determined the sensitivity of the lever sign test for the clinical diagnosis of ACL tears during real-life situations encountered by mountain physicians. This sensitivity was lower than expected. The Lachman test, on the other hand, showed a very high sensitivity. It remains the test of choice for the clinical diagnosis of ACL tears in patients with knee injuries. Therefore, the lever sign test can complement the Lachman test but is not a substitute for it.

LEVEL OF EVIDENCE

II.

Knee Ligament Sprains: Diagnosing Anterior Cruciate Ligament Injuries by Patient Interview. Development and Evaluation of the Anterior Cruciate Ligament Injury Score (ACLIS)

BACKGROUND

Knee ligament sprains are a common reason for emergency-room visits. Initially, the often difficult physical examination provides limited information, creating a risk of missing cruciate-ligament injuries, which can result in substantial functional impairments. No simple tool is available to emergency and primary-care physicians for decisions regarding specialist referral of patients with knee ligament sprains. An easy to use clinical score for the emergency setting would help identify patients at high risk of anterior cruciate ligament (ACL) tears after knee ligament sprains. The primary objective of this study, in two separate cohorts with acute knee injuries, was to develop, then validate a score for assessing the probability of ACL tear and, therefore, the need for specialist referral.

HYPOTHESIS

A score based on patient-interview information with a cut-off associated to good sensitivity and positive predictive value (PPV) for ACL tears can be developed.

MATERIAL AND METHODS

A literature review identified seven items to be used in the score: pivoting and contact activity at the time of injury, perceived cracking sound, sensation of dislocation, joint effusion, suggestive mechanism, inability to resume the activity, and immediate sensation of instability upon walking. To select the most relevant items, we recruited a development cohort of 228 patients (127 males and 101 females) with a mean age of 32±9 years who were seen for knee injuries between November 2017 and November 2018 at three healthcare institutions; 183 (80%) had ACL tears. The score was then tested in a validation cohort of 121 patients (79 males and 42 females) with a mean age of 28±2.5 years seen at two healthcare institutions between November 2019 and November 2020; 81 (67%) had ACL tears. In all patients, the diagnosis of ACL tear was confirmed by a specialist examination and magnetic resonance imaging.

RESULTS

Four items proved both sensitive and specific for ACL injury and were combined into the score: an immediate sensation of knee instability, an inability to resume the sports activity, a sensation of dislocation, and injury during a pivoting-contact activity. Patient report of two or more of these four criteria had 96% sensitivity and 66% specificity for ACL tear, with a PPV of 91% and an NPV of 83%. Results were similar in the validation cohort, confirming that a cut-off of at least two of the four items strongly suggested an ACL tear, with 94% sensitivity, 56% specificity, a PPV of 82% and an NPV of 82%.

CONCLUSION

The ACLIS score performs well for the emergency-room diagnosis of ACL tear, with 95% sensitivity, 62% specificity, an 88% PPV, and an 82% NPV. Patients with ACLIS scores of 2 or more probably require specialist referral with or without magnetic resonance imaging. The ACLIS score could be used routinely in emergency departments to decrease the proportion of patients with undiagnosed ACL tears.

LEVEL OF EVIDENCE

III, prospective case-control study of a diagnostic score.

Early impairment of cartilage poroelastic properties in an animal model of ACL tear

BACKGROUND

In more than 50% of cases, anterior cruciate ligament (ACL) lesions lead to post-traumatic osteoarthritis. Ligament reconstruction stabilizes the joint, but the tear seems to impair the poroelasticity of the cartilage: synovial membrane fluid inflammation is observed 3 weeks after tearing. There have been some descriptions of visible cartilage changes, but poroelasticity has never been analyzed at this early stage. The present animal study aimed to determine (1) whether cartilage showed early poroelastic deterioration after ACL tear; (2) whether an impairment correlated with macroscopic changes; and (3) whether cartilage poroelasticity deteriorated over time.

HYPOTHESIS

In the days following trauma, cartilage poroelasticity is greatly impaired, without macroscopically visible change.

MATERIAL AND METHODS

ACL tear was surgically induced in 18 New-Zealand rabbits. Cartilage poroelasticity was assessed on indentation-relaxation test in 3 groups: "early", at 2 weeks postoperatively (n=6), "mid-early" at 6 weeks (n=6) and in a non-operated control group ("non-op"). Macroscopic changes were scored in the same groups.

RESULTS

Poroelastic impairment was greatest at the early time-point (2 weeks). Permeability ranged from a mean 0.08±0.05×10^-15 m⁴/Ns (range, 0.028-0.17) in the "non-op" group to 1.03±0.60×10^-15 m⁴/Ns (range, 0.24-2.15) in the "early" group (p=0.007). Shear modulus ranged from 0.53±0.11MPa (range, 0.36-0.66) to 0.23±0.10MPa (range, 0.12-0.43), respectively (p=0.013). Macroscopic deterioration, on the other hand, differed significantly only between the "mid-early" and the "non-op" groups: p=0.011 for cartilage deterioration and p=0.008 for osteophyte formation. At the "mid-early" time point, poroelastic deterioration was less marked, with 0.33±0.33×10^-15 m⁴/Ns permeability (range, 0.06-1.06) and shear modulus 0.30±0.10MPa (range, 0.13-0.41: respectively p=0.039 and p=0.023 compared to the "non-op" group.

DISCUSSION

The severe rapid deterioration in poroelasticity following ACL tear in an animal model, as notably seen in increased permeability, corresponds to changes in cartilage microstructure, with easier outflows of interstitial fluid. This mechanical degradation may underlie onset of microcracks within the cartilage, leading to physiological loading that the cartilage by its nature is unable to repair. Further investigations are needed to correlate these experimental data with clinical findings.

LEVEL OF EVIDENCE

III; comparative study with control group.

Predictors of Osteoarthritis Development at a Median 25 Years After Anterior Cruciate Ligament Reconstruction Using a Patellar Tendon Autograft

BACKGROUND

Few studies have investigated the outcome ≥20 years after an anterior cruciate ligament reconstruction (ACLR) with a bone-patellar tendon-bone autograft, and there is a wide range in the reported rates of radiographic osteoarthritis (OA).

PURPOSE

To report on radiographic OA development and to assess risk factors of knee OA at a median 25 years after ACLR with a bone-patellar tendon-bone autograft.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Unilateral ACLRs performed at a single center from 1987 to 1994 were included (N = 235). The study population was followed prospectively with clinical testing and questionnaires. Results from the 3-month, 12-month, and median 25-year follow-up are presented. In addition, a radiographic evaluation was performed at the final follow-up. Radiographic OA was defined as Kellgren-Lawrence grade ≥2 or having undergone ipsilateral knee replacement surgery. Possible predictors of OA development included patient age, sex, time from injury to surgery, use of a Kennedy ligament augmentation device, any concomitant meniscal surgery, and return to preinjury sports after surgery.

RESULTS

At long-term follow-up, 60% (141/235) of patients had radiographic OA in the involved knee and 18% (40/227) in the contralateral knee (P < .001). Increased age at surgery, male sex, increased time between injury and surgery, a Kennedy ligament augmentation device, and medial and lateral meniscal surgery were significant predictors of OA development in univariate analyses. Return to preinjury level of sports after surgery was associated with less development of OA. In the multivariate model, medial meniscal surgery and lateral meniscal surgery were independently associated with OA development. The adjusted odds ratio was 1.88 (95% CI, 1.03-3.43; P = .041) for medial meniscal surgery and 1.96 (95% CI, 1.05-3.67; P = .035) for lateral meniscal surgery. Patients who had developed radiographic signs of OA had significantly lower Knee injury and Osteoarthritis Outcome Score and Lysholm scores at long-term follow-up.

CONCLUSION

At 25 years after ACLR, 60% of patients had developed OA in the involved knee, and these patients reported significantly lower subjective outcomes. Medial meniscal surgery and lateral meniscal surgery were independent predictors of OA development at long-term follow-up.

Fracture Risk With Patella Resurfacing During Total Knee Arthroplasty After Anterior Cruciate Ligament Reconstruction Using Bone-Patella-Bone Autograft: A Biomechanical Analysis

Background

Anterior cruciate ligament (ACL) tears are common injuries. Ipsilateral bone patellar tendon bone (BPTB) autograft has been frequently used for ACL reconstructions. A large percentage of patients who sustain ACL ruptures develop early osteoarthritis and require total knee arthroplasty (TKA). When patients with previous BPTB autograft for an ACL tear undergo TKA, there may be an increased risk of fracture after patellar resurfacing.

Methods

There were 20 artificial Sawbones and 10 cadaveric patellae resurfaced. To simulate the presence of a previous BPTB autograft, a bone plug was removed from the anterior surface of the patellae and was resurfaced with a cemented patellar button. Biomechanical testing was performed to determine the compressive load to fracture of patellae with and without previous BPTB autograft.

Results

The average maximum load to failure for the artificial Sawbones patellae without a previous BPTB autograft was 4551.40 N ± 753.12 compared with 2855.39 N ± 531.46 with a previous BPTB autograft (P < .001). The average maximum load to failure for the cadaveric patellae without a previous BPTB autograft was 7256.37 N ± 1473.97 compared with 5232.22 N ± 475.04 with a previous BPTB autograft (P = .021).

Conclusions

The results demonstrate a significantly lower maximum load to failure of a resurfaced patella in the presence of a previous BPTB autograft. This can be used to aid in the decision of whether to resurface the patellae in these patients and to educate patients that the presence of a previous BPTB autograft may be an increased risk factor for patella fracture after TKA.

Clinical Outcomes and Osteoarthritis at Very Long-term Follow-up After ACL Reconstruction: A Systematic Review and Meta-analysis

Background:

Few studies on outcomes after anterior cruciate ligament (ACL) reconstruction (ACLR) have provided insight into the very long-term effects of this procedure.

Purpose:

To systematically review the outcomes, failure rate, incidence, and predictors of osteoarthritis (OA) for different ACLR techniques at a minimum 20-year follow-up.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A search of the PubMed, SCOPUS, and Cochrane databases was performed on June 2020 for studies of patients who underwent ACLR and had a minimum follow-up of 20 years. We extracted data on patient and surgical characteristics, patient-reported outcomes (Lysholm score, subjective International Knee Documentation Committee [IKDC] score, Knee injury and Osteoarthritis Outcome Score [KOOS], and Tegner score), clinical outcomes (IKDC grade, pivot shift, Lachman, and KT-1000 laxity), degree of OA (Kellgren-Lawrence, Ahlbäck, and IKDC OA grading), revisions, and failures. Relative risk (RR) of OA between the operated and contralateral knees was calculated as well as the pooled rate of revisions, failures, and conversion to total knee arthroplasty (TKA).

Results:

Included were 16 studies (N = 1771 patients; mean age, 24.8 years; mean follow-up, 22.7 years); 80% of the patients underwent single-bundle bone–patellar tendon–bone (BPTB) reconstruction. The average Lysholm (89.3), IKDC (78.6), and KOOS subscale scores were considered satisfactory. Overall, 33% of patients had “abnormal” or “severely abnormal” objective IKDC grade, 6.7% had KT-1000 laxity difference of ≥5 mm, 9.4% had Lachman ≥2+, and 6.4% had pivot shift ≥2+. Signs of OA were reported in 73.3% of patients, whereas severe OA was reported in 12.8%. The operated knee had a relative OA risk of 2.8 (P < .001) versus the contralateral knee. Identified risk factors for long-term OA were male sex, older age at surgery, delayed ACLR, meniscal or cartilage injuries, BPTB autograft, lateral plasty, nonideal tunnel placement, residual laxity, higher postoperative activity, and postoperative range of motion deficits. Overall, 7.9% of patients underwent revision, and 13.4% of ACLRs were considered failures. TKA was performed in 1.1% of patients.

Conclusion:

Most patients had satisfactory subjective outcomes 20 years after ACLR; however, abnormal anteroposterior or rotatory laxity was found in nearly 10% of cases. The presence of radiographic OA was high (RR 2.8 vs uninjured knee), especially in patients with concomitant meniscal or cartilage injuries, older age, and delayed surgery; however, severe OA was present in only 12.8% of cases, and TKA was required in only 1.1%.

Anterior cruciate ligament reconstruction in the over-50s. A prospective comparative study between surgical and functional treatment

INTRODUCTION

In patients aged over-50 years, although data are sparse, results of anterior cruciate ligament (ACL) surgery are good if selection is correctly performed. However, non-operative treatment is usually proposed for this age group, as patients generally prefer just to scale down their sports activities. Non-operative results are acceptable, but with a high risk of residual instability, secondary lesions and lifestyle alteration. The main aim of the present study was to compare results between surgical versus non-surgical treatment of ACL tear in over-50 year-olds. Secondary objectives comprised assessing prognostic factors for poor functional outcome, and comparing the 2 groups epidemiologically to identify clinical decision-making factors. The study hypothesis was that results are comparable between operative and non-operative treatment of ACL tear.

MATERIAL AND METHOD

Three hundred twenty patients were followed up prospectively: 92 non-surgical (NS group) and 288 surgical (S group). Classical epidemiological data were collected. Clinical laxity, differential laximetry, KOOS, IKDC, Tegner and ACL-RSI scores and radiologic assessment were collected pre- and postoperatively, as were intraoperative data. Early and late complications were collected.

RESULTS

All patients were followed up. Patients were principally female, and were older, less athletic, with more stable knee and less severe functional impact in the NS group. Functional scores improved in both groups, and especially in group S, where sports scores were also better. In the NS group, laximetry at follow-up correlated with preoperative marked pivot-shift (p=0.024). Severe differential laxity was predictive of poor IKDC score (p=0.06). In the S group, laximetry at follow-up correlated with preoperative explosive pivot-shift (p<0.001), lateral meniscal lesion (p=0.007), use of hamstring tendon (p=0.007), and non-operated early complications (p=0.004). Factors for poor global KOOS score in group S comprised female gender (p<0.001), high BMI (p<0.001) and skiing (p=0.038). Factors for poor Tegner scores comprised skiing or team sport (p<0.05), isolated moderate medial osteoarthritis (p=0.01), and non-operated early complications (p=0.022). Factors for poor IKDC score comprised female gender (p=0.064), and non-operated early complications (p=0.019). Complications did not differ between groups.

DISCUSSION/CONCLUSION

Results were satisfactory in both groups, with significant improvement in functional scores, but were better in group S. For NS patients, pivot sport was barely feasible and sports activity scores decreased. In case of severe laxity at diagnosis, surgical treatment should be proposed.

LEVEL OF EVIDENCE

III; non-randomized prospective comparative series.

Femur originated genu varum in a patient with symptomatic ACL deficiency: a case report and review of literature

Background

Anterior cruciate ligament (ACL) injury may be associated with genu varum. There are a few indications in which the varus deformity can be corrected at the time of ACL reconstruction. However, as the genu varum originates mostly from the tibia and the simultaneous presence of ACL deficiency and femur originated genu varum is uncommon, only a few papers have described their management for ACL deficient patients with femur originated genu varum.

Case presentation

A young patient visited our clinic with a complaint of right knee pain and giving way. Further work up revealed a full mid substance ACL tear, mild medial knee osteoarthritis and femur originated genu varum of his right knee. He was managed with simultaneous ACL reconstruction and distal femoral valgus osteotomy.

Conclusions

Any corrective osteotomy for genu varum should be performed at center of rotation angle. Isolated ACL reconstruction in patients with simultaneous ACL deficiency and genu varum may hasten the knee degeneration.

Level of evidence

IV

Clinical and Radiographic Outcomes of Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Graft and Femoral Cortical Button Fixation at Minimum 20-Year Follow-up

BACKGROUND

The short-term outcomes of anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone or hamstring tendon (HT) graft are excellent with good clinical stability and patient-reported outcomes. Although some studies have reported the long-term outcomes of bone-patellar tendon-bone graft ACL reconstruction, few have reported the outcomes of HT graft ACL reconstruction.

PURPOSE

To assess clinical and radiographic outcomes of HT graft ACL reconstruction with femoral cortical button fixation at a minimum 20-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A prospective study was performed in which all patients undergoing isolated transtibial primary ACL reconstruction between 1994 and 1996 with HT graft and femoral cortical button fixation were assessed clinically and radiographically. Follow-up was obtained in 48 of 94 patients (51%). Median (interquartile range) age at operation was 31 years (26-39 years); median follow-up was 21 years (20-22 years); 65% were male; and 48% had meniscal injury at surgery and underwent partial meniscectomy. Graft rupture, reoperation, and contralateral injury rates were assessed; clinical stability was measured using the KT-1000 arthrometer; patient-reported outcomes were assessed (International Knee Documentation Committee [IKDC], Lysholm, Forgotten Joint Score, Tegner activity, Knee injury and Osteoarthritis Outcome Score [KOOS], Anterior Cruciate Ligament Quality of Life [ACL-QOL], EuroQol 5-Dimension 5-Level [EQ-5D-5L]); and radiographic osteoarthritis (defined as Kellgren-Lawrence grade ≥2) was assessed for the ipsilateral and the contralateral knee.

RESULTS

Graft rupture occurred in 4 patients (8%), contralateral injury in 4 patients (8%), and reoperation in 15 patients (31%), which consisted mainly of meniscal tears or hardware removal. In patients with an intact graft, excellent patient-reported outcome measures (PROMs) were noted, with a median Lysholm of 90 (78-100), subjective IKDC of 86 (72-95), and KOOS-Sports of 86 (58-100). There was low awareness of the operated knee (Forgotten Joint Score, 81 [60-96]) and good quality of life (ACL-QOL, 85 [75-94]; EQ-5D-5L, 0.87 [0.83-1.00]). Median side-to-side difference, as measured with the KT-1000 arthrometer, was 1 mm (-1 to 3 mm). Radiographic osteoarthritis was evident in 49% of ipsilateral and 10% of contralateral knees and was associated with meniscectomy at index surgery and decreased PROMs at follow-up.

CONCLUSION

Long-term outcomes of transtibial HT graft ACL reconstruction with femoral cortical button fixation are generally good with a low failure rate, low awareness of the operated knee, and good clinical stability. Radiographic osteoarthritis was evident in approximately half of the patients at 20-year follow-up and was associated with meniscectomy at index surgery and decreased PROMs at follow-up.