Evaluation of Quadriceps Strength Post-medial Patellofemoral Ligament Reconstruction Using Quadriceps Tendon Autografts

Medial patellofemoral ligament is a part of the vastus medialis obliquus and vastus intermedius aponeuroses attaching to the medial epicondyle

PURPOSE

This study aimed to investigate the bony surface characteristic of the femoral attachment of the medial patellofemoral ligament (MPFL) and the correlation between the relevant layered structures, including muscular aponeurosis and the joint capsule, which contribute to patellofemoral joint (PFJ) stability.

METHODS

The morphology of the medial aspect of the medial condyle using micro-computed tomography and analysed cortical bone thickening in 24 knees was observed. For the macroscopic and histological analyses, 21 and 3 knees were allocated, respectively. The Kruskal-Wallis one-way analysis of variance test with Dunn post hoc testing was performed for statistical analysis.

RESULTS

At the level of the adductor tubercle, there were no significant differences in cortical bone thickness. At the level of the medial epicondyle (MEC), cortical bone thickness was considerably greater than that in other areas of the medial condyle (mean ± standard deviation, 0.60 ± 0.20 mm; p < 0.0001). Macroscopic analysis revealed that the deep aponeurosis of the vastus medialis obliquus and the tendinous arch of the vastus intermedius distally formed the composite membrane and adjoined to the joint capsule to firmly attach to MEC, which was located at 41.3 ± 5.7 mm posterior and 14.2 ± 3.1 mm superior to the joint cartilage. Histological analysis showed a composite membrane and adjoining capsule attached to MEC via fibrocartilage.

CONCLUSION

MPFL could be interpreted as part of the deep aponeurosis of the vastus medialis obliquus (VMO) and the tendinous arch of the vastus intermedius, which combined with the joint capsule to attach to MEC. The cortical bone thickening indicated that the tensile stresses were loaded on MEC in aged cadavers. Involvement of VMO and vastus intermedius aponeuroses in restored graft of MPFL could utilise the dynamic stability of surrounding muscles to mimic a native structure.

The Superficial "Swing-Down" Quadriceps Tendon Autograft Is a Viable Option for Medial Patellofemoral Ligament Reconstruction: A Systematic Review

PURPOSE

The purpose of this systematic review is to ascertain the reported clinical outcomes and complication profiles of medial patellofemoral ligament (MPFL) reconstruction performed using a superficial "swing-down" quadriceps tendon autograft.

METHODS

Three databases (PubMed, EMBASE, and MEDLINE) were searched from January 1, 2000, to April 06, 2020. Keywords used in the search included: "medial patellofemoral ligament" and "reconstruction". After screening based on inclusion and exclusion criteria, patient demographics, graft type, outcomes, and complications were extracted. Methodological Index for Non-Randomized Studies criteria were used to assess the quality of each included study.

RESULTS

Eleven studies were included, comprising data from 226 patients with mean follow up ranging from 12 to 38 months. All reconstructions used a superficial "swing-down" quadriceps tendon autograft fixed at 20-30 degrees of knee flexion where reported. Eight of eleven studies reported significant improvement in patient reported outcomes such as Kujala score, Lysholm score, and Tegner score. The mean preoperative Kujala score ranged from 35.8 to 82.1 (167 patients), while the mean postoperative Kujala score ranged from 88.4 to 94.8 (197 patients). The mean of the preoperative Lysholm score ranged from 43.3 to 79.3 (77 patients), while the mean of the postoperative Lysholm score ranged from 81.9 to 90.9 (99 patients). The I² statistic for Lysholm and Kujala scores was 94% and 97%, respectively. Across data reported on 194 patients, there was no incidence of patellar redislocation, patellar fracture, or graft site morbidity.

CONCLUSION

The quadriceps tendon produced improved clinical outcomes with low rates of recurrent postoperative patellar dislocation. These data suggest that the quadriceps tendon remains a suitable alternative for MPFL reconstruction and should remain part of the arsenal of knee ligament surgeons.

LEVEL OF EVIDENCE

Systematic review of Level III and IV studies.