Medial patellofemoral ligament reconstruction using a central strip of the quadriceps tendon in patients with recurrent patellar instability: a prospective case series

Medial Patellofemoral Ligament Reconstruction Using Pedicled Quadriceps Tendon Autograft Yields Similar Clinical and Patient-Reported Outcomes but Less Donor-Site Morbidity Compared With Gracilis Tendon Autograft

PURPOSE

To compare clinical and patient-reported outcome measures (PROMs) in patients with recurrent patellar dislocation after medial patellofemoral ligament (MPFL) reconstruction using either a gracilis tendon (GT) or quadriceps tendon autograft (QT).

METHODS

All MPFL reconstruction performed between 2017 and 2019 were reviewed retrospectively. Only patients with isolated MPFL reconstruction, without any major patellofemoral risk factors and a minimum follow-up of 24 months, were included in the study. Patients were matched with respect to sex, age, and body mass index. All patients were evaluated clinically and using PROMs.

RESULTS

A total of 64 patients with an average follow up of 28.7 ± 7.5 months were included in this study. The mean Kujala score (GT: 84.8 ± 12.9, QT: 88.9 ± 10.1), Lysholm score (GT: 89.4 ± 10.2, QT: 88.4 ± 5.0), and visual analog scale score for pain (GT: 1.9 ± 1.8, QT: 1.1 ± 1.3) did not significantly differ between both groups. Tegner activity level was significantly greater (P = .027) in the QT group (5.5 ± 1.9) compared with the GT group (4.6 ± 1.8), but within the minimal clinically important differences. Occasional patellar instability events, but no recurrent dislocation, were reported in 12.5% in the GT group and 6.3% in the QT group (P = .39). Of all patients, 90.6% in the QT and 68.8% in the HT group exceeded the PASS for the Kujala score (P = .06). Significantly more patients (59.4%) treated with GT reported donor-site morbidity in the form of sensitivity deficit at the lower leg compared with those treated with QT (3.1%, P = .001).

CONCLUSIONS

GT and QT MPFL reconstruction have comparable PROMs and patellar redislocation rates 2 years' postoperatively. Significantly more patients treated with GT reported lower-leg sensitivity deficit compared with those treated with QT.

LEVEL OF EVIDENCE

Level III, retrospective case-control study.

Medium to long-term outcomes of medial patellofemoral ligament reconstruction using the superficial quadriceps versus a hamstring autograft in patellar instability patients

Medial patellofemoral ligament (MPFL) reconstruction is a standard procedure in patellar dislocation patients. Superficial quadriceps autografts (QA) and hamstring autografts (HA) are popular graft choices in MPFL reconstruction with the lack of directly compared clinical studies between both methods. A total of 43 patellar instability patients, who underwent QA and HA for patellar stabilization at a specified center between 2012 and 2021, were retrospectively reviewed. 21 QA and 22 HA patients were 52.4% of males and 47.6% females with a median age of 25 years (range 12-58) in the QA group, while 63.6% were females with a median age of 21 years (range 14-58) in the HA group. The mean follow-up period was 46.9 months (range 24-77) in QA and 61 months (range 24-100) in the HA group. At the final follow-up, no complications were observed with either technique. No patients presented with recurrent dislocations after surgery. There was no statistically significant difference in postoperative mean Kujala scores (QA = 94.9+/- 4.1 and HA = 94.2+/- 8.0, p = 0.73) or the mean Lysholm scores (QA = 94.1+/- 5.0 and HA = 93.2+/- 7.0, p = 0.61).

Is the patella apprehension test a valid diagnostic test for patellar instability? A systematic review

Introduction

Patellar instability can arise from a traumatic event with anatomical predisposing factors increasing the risk of dislocation. Accurate diagnosis is required to initiate appropriate treatment. We aimed to evaluate the patella apprehension test (PAT) as a method to diagnose patellar instability.

Methods

The PRISMA diagnostic test accuracy checklist was followed. The review protocol was registered on PROSPERO with registration number CRD42022357898. Electronic databases, currently registered studies, conference proceedings and the reference lists of included studies were searched. A narrative synthesis evaluated the validity of the PAT as a method of diagnosing patellar instability.

Results

A total of 4867 records were screened in the initial search. Of these, 34 articles satisfied the inclusion criteria, assessing 1139 knees of 1046 patients. The PAT was found to have a high sensitivity and specificity. Its intra and inter-rater reliability was highly variable among studies. Studies reporting patellar instability correction following surgery also found a decrease in the number of patients exhibiting a positive PAT.

Conclusion

Current evidence suggests that the PAT has a high sensitivity and specificity. The intra- and inter-rater validities of the PAT are widely variable due to its subjective nature. Thus, though the PAT can be used to provide a provisional clinical diagnosis of patellar instability, formal functional assessment and imaging should be performed to confirm the diagnosis. Further research should explore the association between a positive PAT and anatomical parameters. In addition, studies comparing the accuracy of the PAT and radiological investigations should be performed.

Isolated medial patellofemoral ligament reconstruction results in similar postoperative outcomes as medial patellofemoral ligament reconstruction and tibial-tubercle osteotomy: a systematic review and meta-analysis

PURPOSE

To determine the effect of isolated medial patellofemoral ligament reconstruction (MPFLR) versus concomitant MPFLR and tibial-tubercle osteotomy (TTO) on patient-reported functional outcomes, rate of patellar redislocation, and rate of return to sport in skeletally mature patients with recurrent patellar instability and lateralization as defined by elevated tibial-tubercle trochlear groove (TT-TG) distance.

METHODS

Three databases MEDLINE, PubMed and EMBASE were searched from inception to July 10th, 2022 for literature outlining the management of patients with TT-TG indices greater than 15 mm with either isolated MPFLR or concomitant MPFLR and TTO procedures. The authors adhered to the PRISMA and R-AMSTAR guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on functional outcomes via the Kujala anterior knee pain score, redislocation rates, return to sport rates, and complications were recorded. The MINORS score was used for all studies to perform a quality assessment of included studies.

RESULTS

A total of 31 studies comprising 1405 patients (1452 knees) were included in this review. The mean Kujala score in 13 studies comprising 848 total patients in the isolated MPFLR group was 85.0 (range 80.9-97.5) compared to a score of 83.7 (range 77.2-94.0) in 14 studies comprising 459 patients in the concomitant group. The mean pooled redislocation rate in 19 studies examining isolated MPFLR procedures comprising 948 patients was 3.1% (95% CI 2.1-4.4%, I² = 7%) as opposed to 3.2% (95% CI 1.9-5.0%, I² = 0%) in 15 studies comprising 486 patients in the concomitant group. The mean pooled return to sport rate in seven studies with 472 total patients in the isolated MPFLR group was 82% (95% CI 78-86%, I² = 16%) compared to a score of 92% (95% CI 78-99%, I² = 58%) in four studies comprising 54 patients in the concomitant group. There were similar complication rates between both treatment groups, including range of motion deficits, fractures, infections, and graft failures.

CONCLUSION

Isolated MPFLR leads to similar anterior knee pain, similar redislocation rates and lower return to sport rates than concomitant MPFLR and TTO procedures in patients with TT-TG distances greater than 15 mm. Information from this review can aid surgeons in their decision to choose MPFLR versus concomitant procedures for this patient population, and can also guide future studies on this topic.

LEVEL OF EVIDENCE

Level IV.

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.