Knee function 30 years after ACL reconstruction: a case series of 60 patients.

Background and purpose - Until now, there have been no studies beyond 30 years after anterior cruciate ligament (ACL) reconstruction. We report knee function a mean 31 years after ACL reconstruction.Patients and methods - This cohort comprised a case series of 60 patients with a mean follow-up of 31 years (28-33) after ACL reconstruction. Patients were evaluated with the International Knee Documentation Committee (IKDC) objective assessment, Knee injury Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale, radiography, and MRI.Results - 30 patients showed an intact ACL graft and 30 a ruptured or missing ACL graft. 40 patients had osteoarthritis in the tibiofemoral compartment and 24 patients in the patellofemoral compartment. Patients with intact ACL grafts scored higher than those with ruptured or missing ACL grafts when it comes to KOOS Sport/Rec. The Hodges Lehmann estimated median difference between groups was 15 (95% CI 0-35). The KOOS scores were lower in the group with ruptured or missing ACL grafts when compared with a healthy-knee reference group of males in terms of Pain, mean difference -8 (CI -15 to -1), Symptoms, mean difference -18 (CI -27 to -9), and Sport/Rec, mean difference -21 (CI -34 to -8). In the group with intact ACL grafts, the KOOS score was lower than a healthy-knee reference group of males in terms of Symptoms, mean difference -12 (CI -21 to -3). Scores for all subgroups of KOOS were higher in patients without osteoarthritis. The IKDC overall clinical assessment outcome was worse in patients with a ruptured or missing ACL graft. The Hodges Lehmann estimated median difference between groups was 1 (CI 0-1).Interpretation - Patients with an intact ACL graft reported higher sports activity and recreation, as measured with KOOS, than patients with a ruptured or missing ACL graft. Patients with severe osteoarthritis reported lower sports activity and recreation, as measured with KOOS.

Higher frequency of osteoarthritis in patients with ACL graft rupture than in those with intact ACL grafts 30 years after reconstruction.

PURPOSE: The aim was to assess the results of anterior cruciate ligament (ACL) reconstruction regarding graft failure, knee laxity, and osteoarthritis (OA) from a longterm perspective. It was hypothesized that intact ACL graft reduces the risk for increased OA development. METHODS: The cohort comprised 60 patients with a median follow-up 31 (range 28-33) years after ACL reconstruction. They were evaluated with magnetic resonance imaging, radiography, KT-1000 arthrometer and the pivot shift test. RESULTS: Out of the 60 patients, 30 (50%) showed an intact ACL graft and 30 (50%) a ruptured or absent ACL graft. Patients with ruptured ACL grafts had more medial tibiofemoral compartment OA than those with an intact ACL graft (p = 0.0003). OA was asymmetric in patients with ruptured ACL grafts with more OA in the medial than in the lateral tibiofemoral compartment (p = 0.013) and the patellofemoral compartment (p = 0.002). The distribution of OA between compartments was similar in patients with an intact ACL graft. KT-1000 values of anterior knee laxity were higher in patients with ruptured compared to those with intact ACL grafts (p = 0.012). Side-to-side comparisons of anterior knee laxity showed higher KT-1000 values in patients with ruptured ACL graft (p = 0.0003) and similar results in those with intact graft (p = 0.09). The pivot shift grade was higher in the group with a ruptured ACL graft (p < 0.0001). CONCLUSIONS: Median 31 (range 28-33) years after ACL reconstruction, 50% of the patients showed an intact ACL graft and no side-to-side difference regarding anterior knee laxity. Patients with ruptured ACL grafts had more OA of the medial tibiofemoral compartment than those with intact ACL grafts. LEVEL OF EVIDENCE: Retrospective cohort study, Level III.

Muscle morphometric effect of anterior cruciate ligament injury measured by computed tomography: aspects on using non-injured leg as control.

BACKGROUND: Anterior cruciate ligament (ACL) tears are common, functionally disabling, and predispose to subsequent injuries and early onset of osteoarthritis in the knee. Injuries result in muscular atrophy and impaired muscular activation. To optimize surgical methods and rehabilitation strategies, knowledge of the effects of ACL injuries on muscles size and function is needed. Asymmetry due to limb dominance implies that the effect of ACL-injury might be different in right-sided and left-sided injuries which, should be taken in account when evaluating the effect of an injury. Evaluation of the effects of injuries is usually made with the contralateral leg as control. The aim of this study is to describe the effect of ACL-injuries on thigh muscle size and also to analyze feasibility of using contralateral limb as control. METHODS: Sixty-two patients scheduled to undergo ACL reconstruction were examined with computed tomography (CT). Muscle cross sectional area (CSA) was recorded for quadriceps, hamstrings, gracilis and sartorius 15 cm above the knee joint. Comparisons were made between the injured and non-injured side and between individuals separated by gender and side of injury. Comparisons were also made for patients with or without concomitant meniscal tear, for patients differing in time between injury and examinations and for patients with different level of physical activity after the injury. RESULTS: Quadriceps CSA was 5% smaller on the injured side. There was an indication that the muscles of the right thigh were generally bigger than those of the left thigh. The difference between the injured and the non-injured side was larger for right-sided injuries than for left-sided. There was also a greater difference in semimembranosus for women than for men. There were no differences related to meniscal injury, time since injury or physical activity. CONCLUSION: The use of contralateral leg for evaluating the effect of ACL-injury is often the only available alternative but our study indicates that the difference in CSA between injured and non-injured side does not necessarily reflect the true degree of atrophy, as there are side differences both in muscle size in general and in the effect of an ACL-injury on muscle size.

Reliability of computed tomography measurements in assessment of thigh muscle cross-sectional area and attenuation.

BACKGROUND: Advancement in technology of computer tomography (CT) and introduction of new medical imaging softwares enables easy and rapid assessment of muscle cross-sectional area (CSA) and attenuation. Before using these techniques in clinical studies there is a need for evaluation of the reliability of the measurements. The purpose of the study was to evaluate the inter- and intra-observer reliability of ImageJ in measuring thigh muscles CSA and attenuation in patients with anterior cruciate ligament (ACL) injury by computer tomography. METHODS: 31 patients from an ongoing study of rehabilitation and muscle atrophy after ACL reconstruction were included in the study. Axial CT images with slice thickness of 10 mm at the level of 150 mm above the knee joint were analyzed by two investigators independently at two times with a minimum of 3 weeks between the two readings using NIH ImageJ. CSA and the mean attenuation of individual thigh muscles were analyzed for both legs. RESULTS: Mean CSA and mean attenuation values were in good agreement both when comparing the two observers and the two replicates. The inter- and intraclass correlation (ICC) was generally very high with values from 0.98 to 1.00 for all comparisons except for the area of semimembranosus. All the ICC values were significant (p < 0,001). Pearson correlation coefficients were also generally very high with values from 0.98 to 1.00 for all comparisons except for the area of semimembranosus (0.95 for intraobserver and 0.92 for interobserver). CONCLUSION: This study has presented ImageJ as a method to monitor and evaluate CSA and attenuation of different muscles in the thigh using CT-imaging. The method shows an overall excellent reliability with respect to both observer and replicate.

Post-operative bracing after ACL reconstruction has no effect on knee joint effusion. A prospective, randomized study.

BACKGROUND: It is unclear what factors contribute to knee joint effusion after anterior cruciate ligament (ACL) injury and reconstruction. Knee homeostasis after injury and surgery is crucial for rehabilitation and knee well-being. We examined if effusion was affected by post-operative bracing, and if patients with effusion fit into a common profile. METHODS: Patients were randomized to wearing or not wearing a post-operative brace for three weeks after ACL reconstruction with semitendinosus-gracilis tendons. Knee joint effusion was detected by computed tomography in 60 patients (22 women), before and three and 12 months after surgery. Joint effusion, clinical and subjective tests were analyzed. RESULTS: This is the first prospective, randomized study on post-operative bracing for patients with a semitendinosus-gracilis graft showed that bracing had no effect on three-months presence of joint effusion. Excessive joint effusion was present in 68% of the patients three months after surgery and was associated to prior meniscus injury (p=0.05) and higher prior Tegner activity level (p=0.006). We found a positive association between longer time from injury to surgery and joint effusion three months post-operatively (rho=0.29, p<0.05). Twelve months post-operatively, joint effusion had diminished to baseline levels. Subjective scores and activity levels were lower for women. Three-months joint effusion predicted lower final outcome scores in women. CONCLUSION: Prior meniscus injury and pre-injury Tegner activity levels are predictive significant variables for excessive knee joint effusion after ACL reconstruction. Post-operative bracing had no effect. A larger clinical cohort is needed to confirm findings of this logistic regression.