The Effectiveness of Anterior Cruciate Ligament Reconstruction on the Patellofemoral Stability and Patellar Height

Abstract

Background: Considering the critical role the anterior cruciate ligament (ACL) plays in knee biomechanics, it is a logical hypothesis that ACL reconstruction (ACLR) will have positive effects on knee kinematics, and stability. Our objective was to investigate the effect of single-bundle ACLR on patellar height, and patellofemoral balance radiologically and clinically.
 Methods: In this prospective study, 87 patients operated with hamstring autograft-used single-bundle ACLR were analyzed. History of dislocation, stability-related physical examination findings, Tegner-Lysholm Knee Scoring Scale, and Kujala Anterior Knee Pain Scale were used for functional assessment. All patients underwent pre-and post-operative magnetic resonance imaging and Insall-Salvati (IS) Index, Caton Deschamps Index, Blackburne-Peel Index, and Patella-patellar tendon (P-PT) angles were measured on T1-weighted sagittal section images. 
 Results: A total of 79 patients (90.8%) achieved excellent or good result, according to Tegner-Lysholm Knee Scoring Scale, and the patients' postoperative 1st year mean Kujala Anterior Knee Pain Score was calculated as 90.4 (Range: 79.1 – 96.4). On physical examination, increased passive patellar translation was observed in 2 patients (2.3%), but the J sign was appeared to be negative in all the patients. While all patellar height indices decreased after reconstruction, only the decrease in IS index was statistically significant (p=0.007). Moreover, the P-PT angle was found to be significantly lower after ACLR (p