Should return to pivoting sport be avoided for the secondary prevention of osteoarthritis after anterior cruciate ligament reconstruction? A prospective cohort study with MRI, radiographic and symptomatic outcomes.

OBJECTIVE: To evaluate if returning to pivoting sport following anterior cruciate ligament reconstruction (ACLR) is associated with longitudinal structural and symptomatic osteoarthritis outcomes. DESIGN: Eighty-one adults aged 18-50 years were followed prospectively 1- to 5-years post-ACLR. Return to pivoting sport was assessed at 1-, 3- and 5-years. Longitudinal changes in osteoarthritis features were evaluated from 1- and 5-year magnetic resonance imaging (MRI)s using MRI Osteoarthritis Knee Score (MOAKS). Radiographic osteoarthritis and self-reported knee symptoms, function and quality of life were assessed using the Osteoarthritis Research Society International (OARSI) atlas and Knee injury Osteoarthritis Outcome Score (KOOS), respectively, at 5 years post-ACLR. Generalised linear models (adjusted for baseline characteristics) assessed whether returning to pivoting sport was associated with risk of worsening osteoarthritis features on MRI, radiographic osteoarthritis and KOOS. RESULTS: Thirty participants returned to pivoting sport 1-year post-ACLR and 50 returned at any time (i.e., 1-, 3- or 5-years). Returning to pivoting sport was not associated with worsening of any MRI osteoarthritis feature (risk ratio (RR) range: 0.59-2.91) or 5-year KOOS (ß range: -2.73-3.69). Returning to pivoting sport at 1-year and up to 5-years post-ACLR was associated with a 50% (RR 0.49, 95%CI 0.10-2.37) and 40% (RR 0.60, 95%CI 0.16-2.17) reduced risk of radiographic osteoarthritis, respectively, but these risk reductions were inconclusive due to wide confidence intervals. CONCLUSION: After ACLR, returning to pivoting sport was not associated with increased risk of worsening knee osteoarthritis features on MRI, radiographic osteoarthritis or knee symptoms. Participation in pivoting sport need not be avoided as part of osteoarthritis secondary prevention strategies.

Knee kinematics and kinetics are associated with early patellofemoral osteoarthritis following anterior cruciate ligament reconstruction.

OBJECTIVE: Patellofemoral osteoarthritis (PFOA) commonly occurs following anterior cruciate ligament reconstruction (ACLR). Our study aimed to compare knee kinematics and kinetics during a hop-landing task between individuals with and without early PFOA post-ACLR. DESIGN: Forty-five individuals (mean ± SD 26 ± 5 years) 1-2 years post-ACLR underwent 3T isotropic MRI scans and 3D biomechanical assessment of a standardised forward hop task. Knee kinematics (initial contact, peak, excursion) in all three planes and sagittal plane kinetics (peak) were compared between 15 participants with early PFOA (MRI-defined patellofemoral cartilage lesion) and 30 participants with no PFOA (absence of patellofemoral cartilage lesion on MRI) using analysis of covariance (ANCOVA), adjusted for age, BMI, sex and the presence of early tibiofemoral OA. RESULTS: Compared to participants without PFOA, those with early PFOA exhibited smaller peak knee flexion angles (mean difference, 95% confidence interval [CI]: -5.2°, -9.9 to -0.4; P = 0.035) and moments (-4.2 Nm/kg.m, -7.8 to -0.6; P = 0.024), and greater knee internal rotation excursion (5.3°, 2.0 to 8.6; P = 0.002). CONCLUSIONS: Individuals with early PFOA within the first 2-years following ACLR exhibit distinct kinematic and kinetic features during a high-load landing task. These findings provide new information regarding common post-ACLR biomechanical patterns and PFOA. Since management strategies, such as altering knee load, are more effective during the early stages of disease, this knowledge will help to inform clinical management of early PFOA post-ACLR.

Outcome of surgery for recurrent patellar dislocation based on the distance of the tibial tuberosity to the trochlear groove.

We evaluated the outcome in a series of patients with recurrent patellar dislocation who had either medial transfer of the tibial tuberosity and lateral release or an isolated lateral release as the primary treatment. The decision to use one or other procedure was based on a pre-operative distance between the tibial tuberosity to the trochlear groove (TTTG) of less than 10 mm to include the tibial tuberosity transfer in addition to the lateral release. Between April 2002 and December 2006, 49 patients (63 knees) underwent one of these procedures. A total of 35 patients (46 knees) was evaluated at a mean of 38 months (13 to 71) post-operatively. Medial transfer of the tibial tuberosity was performed in 33 knees and isolated lateral release in the remaining 13. Evaluation included the International Knee Documentation Committee (IKDC), the Kujala and the Short-form 36 scores. From the tibial tuberosity group 23 knees also underwent radiological examination at follow-up. There were further episodes of patellar dislocation in six of the 46 knees available for review. Further dislocation was noted in five of 33 knees (15.2%) in the tibial tuberosity transfer group and in one of 13 knees (7.7%) in the lateral release group. The mean subjective IKDC score was 80.4 (sd 11.6), the mean Kujala score 88 (sd 8.2) and the mean objective IKDC score was 79% normal and 21% nearly normal. The mean post-operative TTTG distance in the tibial tuberosity transfer group was 8.9 mm (3.2 to 15.7) compared with the mean pre-operative value of 16.8 mm (12.2 to 24.4).