BACKGROUND: The incidence of the patellofemoral joint chondral lesions after anterior cruciate ligament reconstruction (ACLR) is disturbingly high. Few studies have assessed the factors affecting patellofemoral joint chondral lesions postoperatively. HYPOTHESIS: The recovery of quadriceps strength after ACLR could be associated with patellofemoral joint cartilage damage. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 88 patients who underwent arthroscopic anatomic double-bundle ACLR with hamstring autografts received second-look arthroscopy at the time of metal staple removal at an average of 24.1 months (range, 12-51 months) postoperatively. All patients underwent standardized isokinetic strength testing for bilateral quadriceps and hamstrings 1 to 2 days before second-look arthroscopy. The patients were divided into 2 groups: Patients in group 1 had a ≥20% deficit on the peak torque measures for quadriceps compared with that of the contralateral knee, whereas those in group 2 had a <20% deficit on peak torque. Cartilage status at the patellofemoral joint and tibiofemoral joint were evaluated by second-look arthroscopy and the Outerbridge classification. Other assessments included the International Knee Documentation Committee (IKDC) score, Tegner and Lysholm scores, side-to-side difference on KT-2000 arthrometer, and range of motion. RESULTS: There were 42 patients included in group 1 and 46 patients in group 2. The mean postoperative quadriceps peak torque of the involved knee compared with the contralateral knee was 70% (range, 57%-80%) in group 1 and 95% (range, 81%-116%) in group 2. For all patients, a significant worsening was seen in the patellar and trochlear cartilage (P = .030 and <.001, respectively) but not at the medial or lateral tibiofemoral joint after ACLR. A significant worsening in the status of both patellar and trochlear cartilage was seen after ACLR in group 1 (P = .013 and =.011, respectively) and of trochlear cartilage in group 2 (P = .006). Significantly fewer severe chondral lesions of the patella were found in group 2 than in group 1 (proportion of patients whose cartilage grade worsened: 26% vs 48%, P < .05; difference in cartilage grade: 0.09 vs 0.62, P < .05). There was no significant difference for trochlear chondral worsening between the 2 groups. No significant differences were detected between the 2 groups in terms of hamstring strength; Lysholm, Tegner, and IKDC scores; KT-2000 arthrometer anterior laxity; or range of motion. CONCLUSION: Greater than 80% recovery of quadriceps strength after ACLR is associated with less severe patellar cartilage damage at short-term follow-up.
BACKGROUND: The incidence of the patellofemoral joint chondral lesions after anterior cruciate ligament reconstruction (ACLR) is disturbingly high. Few studies have assessed the factors affecting patellofemoral joint chondral lesions postoperatively. HYPOTHESIS: The recovery of quadriceps strength after ACLR could be associated with patellofemoral joint cartilage damage. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 88 patients who underwent arthroscopic anatomic double-bundle ACLR with hamstring autografts received second-look arthroscopy at the time of metal staple removal at an average of 24.1 months (range, 12-51 months) postoperatively. All patients underwent standardized isokinetic strength testing for bilateral quadriceps and hamstrings 1 to 2 days before second-look arthroscopy. The patients were divided into 2 groups: Patients in group 1 had a ≥20% deficit on the peak torque measures for quadriceps compared with that of the contralateral knee, whereas those in group 2 had a <20% deficit on peak torque. Cartilage status at the patellofemoral joint and tibiofemoral joint were evaluated by second-look arthroscopy and the Outerbridge classification. Other assessments included the International Knee Documentation Committee (IKDC) score, Tegner and Lysholm scores, side-to-side difference on KT-2000 arthrometer, and range of motion. RESULTS: There were 42 patients included in group 1 and 46 patients in group 2. The mean postoperative quadriceps peak torque of the involved knee compared with the contralateral knee was 70% (range, 57%-80%) in group 1 and 95% (range, 81%-116%) in group 2. For all patients, a significant worsening was seen in the patellar and trochlear cartilage (P = .030 and <.001, respectively) but not at the medial or lateral tibiofemoral joint after ACLR. A significant worsening in the status of both patellar and trochlear cartilage was seen after ACLR in group 1 (P = .013 and =.011, respectively) and of trochlear cartilage in group 2 (P = .006). Significantly fewer severe chondral lesions of the patella were found in group 2 than in group 1 (proportion of patients whose cartilage grade worsened: 26% vs 48%, P < .05; difference in cartilage grade: 0.09 vs 0.62, P < .05). There was no significant difference for trochlear chondral worsening between the 2 groups. No significant differences were detected between the 2 groups in terms of hamstring strength; Lysholm, Tegner, and IKDC scores; KT-2000 arthrometer anterior laxity; or range of motion. CONCLUSION: Greater than 80% recovery of quadriceps strength after ACLR is associated with less severe patellar cartilage damage at short-term follow-up.
Authors: Erin M Macri; Brooke E Patterson; Kay M Crossley; Josh J Stefanik; Ali Guermazi; Evelina Blomqwist; Karim M Khan; Tim S Whitehead; Hayden G Morris; Adam G Culvenor Journal: Eur J Radiol Date: 2019-01-31 Impact factor: 3.528
Authors: Caroline Brunst; Matthew P Ithurburn; Andrew M Zbojniewicz; Mark V Paterno; Laura C Schmitt Journal: J Orthop Res Date: 2021-04-08 Impact factor: 3.494
Authors: Chang-Wan Kim; Ali Hosseini; Lin Lin; Yang Wang; Martin Torriani; Thomas Gill; Alan J Grodzinsky; Guoan Li Journal: J Orthop Translat Date: 2017-07-02 Impact factor: 5.191