Medial patellofemoral ligament reconstruction using an autograft or allograft for patellar dislocation: a systematic review

Medial patellofemoral ligament reconstruction with an extensor hallucis longus allograft: a retrospective study of 45 cases

Reconstruction of the Medial Patellofemoral Ligament (MPFL) has become the procedure of choice in patients with patellar instability. The type of graft used for reconstruction is controversial. The purpose of this study was to analyze and describe the clinical and radiological results achieved with a MPFL reconstruction performed using an extensor hallucis longus allograft. This work is a retrospective study of 41 patients (45 knees) who underwent MPFL reconstruction using an extensor hallucis longus allograft. The patellar apprehension test, Kujala scale, and EQ-5D European quality of life scale were evaluated preoperatively and postoperatively at 24 months. Complications, recurrence rate, time to return to sports, and satisfaction with the procedure were also assessed. Statistically significant differences were observed between pre- and postoperative variables on the Kujala scale (p < .001) and the EQ-5D (p < .001). The isolated MPFL presented an increase on the Kujala scale of 41.9 ± 13.4, in contrast to the reconstruction with tibial tubercle osteotomy with an increase of 29.4 ± 16.6 (p = 0.031). MPFL reconstruction with an extensor hallucis longus allograft is a suitable alternative in patients with patellofemoral instability because it offers clinically and radiologically satisfactory results. MPFL reconstruction combined with a tibial tubercle osteotomy can offer inferior functional outcomes to the isolated reconstruction.

Medial patellofemoral ligament reconstruction appears to be a better treatment than repair, proximal realignment, or conservative management for primary patellar dislocation: A network meta-analysis

BACKGROUND

The purpose of this study was to compare the functional outcomes and re-dislocation rates of medial patellofemoral ligament (MPFL) reconstruction, MPFL repair, combined proximal realignment (CPR), and conservative management for primary patellar dislocation by conducting a systematic literature search of the available studies. The hypothesis was that MPFL repair and MPFL reconstruction would be better options for treating primary patellar dislocation.

METHODS

Randomized controlled trials or prospective studies of primary patellar dislocation treated with MPFL reconstruction, MPFL repair, CPR, or conservative management were identified from the MEDLINE, EMBASE, and the Cochrane Library databases through December 31, 2021. A total of 626 patients met the prespecified inclusion criteria. The methodological quality of each study was assessed using a risk of bias table, Detsky quality index, and Newcastle-Ottawa Scale. The end-point data collected included comparisons of the mean in functional scores on knee outcomes scales and the number of patients who experienced re-dislocation. A network meta-analysis of the relevant literature was performed to investigate which treatment showed better outcomes.

RESULTS

In total, 10 trials were included in this study. There was no statistically significant difference in the subgroup analysis in terms of the functional outcomes among MPFL reconstruction, MPFL repair, CPR, and conservative management. However, MPFL reconstruction showed statistically significantly better outcomes than MPFL repair, CPR, or conservative management in terms of the re-dislocation rate. Additionally, surface under the cumulative ranking curve percentage showed that MPFL reconstruction had a lower probability of re-dislocation than MPFL repair even though there was no significant difference (0.24, 95% confidence interval: 0.02-2.91).

CONCLUSION

Using a network meta-analysis, this meta-analysis showed that there was no significant difference in functional outcomes in a subgroup analysis. In re-dislocation subgroup analysis, MPFL repair and MPFL reconstruction produced significantly better results than other treatments. Also, surface under the cumulative ranking curve percentage showed that MPFL reconstruction had a lower probability of re-dislocation than MPFL repair.

Reliability of the TT-TG Index Versus TT-TG Distance on MRI: Morphometric Analyses in Asian Children and Adolescents

Background

The tibial tuberosity-trochlear groove (TT-TG) distance measured on magnetic resonance imaging (MRI) is commonly used to decide the treatment for patellar instability; however, the patient's joint size is not considered in this measurement. The TT-TG index has been proposed as a knee size-adjusted measurement for tibial tuberosity location.

Purpose

To evaluate the reliability of the TT-TG index compared with the TT-TG distance by analyzing variations in measurement according to age and sex in a pediatric Asian population.

Study Design

Cohort study (diagnosis); Level of evidence, 3.

Methods

A total of 698 knee MRI scans were collected in patients between 4 and 18 years of age who did not have any patellofemoral problems. Patient age, sex, height, and weight were recorded. The scans were divided into 5 groups according to patient age (4-6 years, 46 scans; 7-9 years, 56 scans; 10-12 years, 122 scans; 13-15 years, 185 scans; and 16-18 years, 289 scans); MRI scans were also divided by sex (497 male, 201 female). Three independent observers measured the TT-TG distance and TT-TG index on each scan, and age- and sex-based differences in the measurements were evaluated after adjusting for body mass index (BMI). The reliability of the measurements was calculated with the intraclass correlation coefficient (ICC).

Results

Good to excellent inter- and intraobserver agreement was found for TT-TG distance (ICC, 0.74) and TT-TG index (ICC, 0.88). The TT-TG distance was significantly different among the groups and increased with age, while variations in the TT-TG index were minimal between age groups and sexes. This finding was also consistent after compensating for the effect of BMI.

Conclusion

The TT-TG distance changed with age, while the TT-TG index was relatively constant. Therefore, the TT-TG index may be more reliable and effective for diagnosing and planning treatment, especially in children and adolescents.

Allografts for Medial Patellofemoral Ligament (MPFL) Reconstruction in Adolescent Patients with Recurrent Patellofemoral Instability: A Systematic Review

This systematic review updates the currently available evidence on medial patella-femoral ligament (MPFL) reconstruction using allografts. The outcomes were measured with patient-reported outcome measures (PROMs), redislocation and complication rates. This study was performed according to the 2020 PRISMA guidelines using the PubMed, Scopus, Web of Science databases, accessed in February 2023. Studies examining the clinical outcomes of MPFL reconstruction with allografts in adolescents and children with recurrent patellofemoral instability (PFI) were included. Data from three trials, including 113 surgical procedures in 121 children, were retrieved. 40% (48/121) of the included patients were girls. The mean age of the patients was 14.7 ± 0.8 years, and the mean follow-up length was 38.1 ± 16.5 months. With MPFL allograft reconstruction, the Kujala score improved by 14.7% (p < 0.0001) and the IKDC by 38.8% (p < 0.0001). The rate of dislocations was 5% (6 of 121), reoperation for instability was 11% (13 of 121), and subluxation was 2% (1 of 47). Conclusion: These results encourage the use of allografts for MPFL reconstruction in adolescent patients with recurrent patellofemoral instability. Though patellofemoral instability is common in clinical practice, the current literature lacks clinical evidence on allograft MPFL reconstruction. Additional high-quality investigations are required to properly establish the long-term advantages of allograft MPFL and its complication rate.

Synthetic graft for medial patellofemoral ligament reconstruction: a systematic review

Background

This systematic review investigates the role of synthetic graft for primary medial patellofemoral ligament (MPFL) reconstruction in patients with recurrent patellofemoral instability, focusing on clinical scores and the rate of complications.

Methods

This systematic review was conducted according to the PRISMA statement. The main online databases were accessed in January 2022 without time constraints. All clinical studies investigating the use of synthetic grafts for MPFL reconstruction were accessed. Revision settings were not considered. Only articles reporting data on patients with recurrent patellofemoral instability were eligible. Studies regarding congenital or acute patellofemoral dislocation were excluded. Only studies performing a follow-up longer than 24 months were considered.

Results

Data on 199 patients [mean age 22.3 (range 19.0–28.0) years] were collected. The mean follow-up was 60.5 (39.0–142.8) months. All the scores of interest improved at last follow-up: Kujala (+ 24.8; P = 0.0002), Lysholm (+ 42.0; P = 0.02), Tegner (+ 1.2; P = 0.03), IKDC (+ 20.9; P = 0.02). Post-operatively, a positive apprehension test was detected in 6.1% (7/115) of patients, and a sensation of instability was reported by 1.5% (3/199) of patients. The rate of re-dislocations was 2.5% (5 of 199 patients), and revision procedures were performed in less than 1% (1 of 199) of patients.

Conclusion

Synthetic graft may be reliable and feasible for primary MPFL reconstruction in patients with recurrent patellofemoral instability.

Simultaneous Medial Patellofemoral Ligament and Medial Quadriceps Tendon-Femoral Ligament Reconstructions Using an Artificial Ligament for Lateral Patella Instability

Recent studies on the detailed anatomy of the medial patellar stabilizer have revealed that the medial patellofemoral ligament (MPFL) not only attaches to the patella but also has fibers that attach to the quadriceps muscle, known as the medial quadriceps tendon femoral ligament (MQTFL). Reconstruction of the medial stabilizer for patellar dislocation that includes both the MPFL and MQTFL may achieve better anatomical and physiological correction. In this Technical Note, we will describe a simultaneous reconstruction technique of the MPFL and MQTFL for patellar dislocation using an artificial ligament.

Comparable outcome for autografts and allografts in primary medial patellofemoral ligament reconstruction for patellofemoral instability: systematic review and meta-analysis

PURPOSE

This study updates the current evidence on the role of allografts versus autografts for medial patellofemoral ligament (MPFL) reconstruction in patients with patellofemoral instability.

METHODS

The study was performed according to the PRISMA guidelines. In March 2021, a literature search in the main online databases was performed. Studies reporting quantitative data concerning primary MPFL reconstruction using an allograft were considered for inclusion. The Coleman Methodology Score was used to assess the methodological quality of the selected articles.

RESULTS

Data from 12 studies (474 procedures) were retrieved. The mean follow-up was 42.2 (15-78.5) months. The mean age was 21.1 ± 6.2 years. 64.9% (285 of 439) of patients were female. At the last follow-up, the Tegner (p < 0.0001), Kujala (p = 0.002) and the Lysholm (p < 0.0001) scores were minimally greater in the autografts. The similarity was found in the rate of persistent instability sensation and revision. The allograft group evidenced a lower rate of re-dislocations (p = 0.003).

CONCLUSION

Allografts may represent a feasible alternative to traditional autograft for MPFL reconstruction in selected patients with patellofemoral instability. Allograft tendons yielded similar PROMs, rates of persistent instability, and revision. Allograft reconstructions tended to have modestly lower re-dislocation rates.

LEVEL OF EVIDENCE

IV.

Hardware-free MPFL reconstruction in patients with recurrent patellofemoral instability is safe and effective

PURPOSE

This systematic review evaluated the clinical outcomes of hardware-free MPFL reconstruction techniques in patients with recurrent patellofemoral instability, focusing on patient-reported outcome measures (PROMs), redislocation rate, and complications. The hypothesis was that hardware-free MPFL reconstruction in patients with recurrent patellofemoral instability is safe and effective.

METHODS

This systematic review was conducted following the PRISMA guidelines. PubMed, Scopus, and Virtual Health Library databases were accessed in October 2021. All the clinical studies investigating the efficacy and feasibility of hardware-free MPFL reconstruction were screened for inclusion. Only studies with a minimum 24-month follow-up were considered eligible. Kujala Anterior Knee Pain Scale improvement and redislocation rate after surgical treatment were evaluated as primary outcomes. The rate of postoperative complications was evaluated as a secondary outcome. The quality of the methodological assessment was assessed using the Modified Coleman Methodology Score.

RESULTS

Eight studies were included in the present systematic review. The quality of the methodological assessment was moderate. Short- to long-term improvement of Kujala score was observed in all included studies. Mean score improvement ranged from + 13.2/100 to + 54/100, with mean postoperative scores ranging from 82/100 to 94/100. Patellar redislocation was observed in 8.33% (8 of 96) patients.

CONCLUSION

Hardware-free MPFL reconstruction with or without associated soft-tissue or bony realignment procedures provided reliable clinical improvements and was associated with a low rate of redislocation in patients with recurrent patellofemoral instability. Advantages such as safety, femoral physis preservation, and comparable complication profiles with implant-based techniques endorse its implementation. Orthopedic surgeons in cost-sensitive environments may also benefit their patients with lower costs, no need for implants, lack of implant-related complications, or surgery for implant removal.

LEVEL OF EVIDENCE

Level IV.

Results and Factors Affecting Clinical Efficacy of Medial Patellofemoral Ligament Reconstruction Using a Gracilis Tendon Suture Technique

Background

This study evaluated the outcomes of medial patellofemoral ligament (MPFL) reconstruction using a gracilis tendon suture technique for patients with patellar instability. Potential factors affecting clinical efficacy were also evaluated.

Methods

This study included 22 patients diagnosed with patellar instability, who underwent MPFL reconstruction using a gracilis tendon. Their mean age was 21.5 years (range, 15–48 years), and the mean follow-up period was 26.8 months (range, 12–66 months). Clinical evaluation included the determination of Kujala, Lysholm, and Tegner scores. Radiographic evaluation included changes in congruence angle and arthritic changes in the patellofemoral joint. Additionally, patients were examined for any complications, including recurrent dislocation. Factors affecting clinical efficacy were also evaluated.

Results

All clinical scores improved at final follow-up. The mean congruence angle improved from 23.6° before surgery to –6.5° at final follow-up. Two of 15 patients developed osteoarthritic changes in the patellofemoral joint. Dislocation recurred in 2 patients with type C trochlear dysplasia, which showed a statistically significant association with recurrent dislocation when compared to type A and B dysplasia (p = 0.026). Kujala scores were significantly lower among patients with abnormal patellar tilts (p = 0.038), and Lysholm scores were significantly lower among patients with femoral internal rotation deformity (p = 0.024).

Conclusions

Satisfactory results were obtained after MPFL reconstruction using a gracilis tendon suture technique for patients with patellar instability. However, dislocation recurred in patients with type C trochlear dysplasia, and clinical efficacy was lower among patients with femoral internal rotation and patellar tilt.

Clinical Comparison of Medial Patellofemoral Ligament Reconstruction With or Without Tibial Tuberosity Transfer for Recurrent Patellar Instability

BACKGROUND

No clear guidelines or widespread consensus has defined a threshold value of tibial tuberosity-trochlear groove (TT-TG) distance for choosing the appropriate surgical procedures when additional tibial tuberosity osteotomy (TTO) should be added to augment medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar instability.

PURPOSE

To compare the clinical outcomes between MPFL reconstruction and MPFL reconstruction with TTO for patients who have patellar instability with a TT-TG distance of 15 to 25 mm.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

We retrospectively analyzed 81 patients who underwent surgical treatment using either MPFL reconstruction or MPFL reconstruction with TTO for recurrent patellar instability with a TT-TG distance of 15 to 25 mm; the mean follow-up was 25.2 months (range, 12.0-53.0 months). The patients were divided into 2 groups: isolated MPFL reconstruction (iMPFL group; n = 36) performed by 2 surgeons and MPFL reconstruction with TTO (TTO group; n = 45) performed by another 2 surgeons. Clinical outcomes were assessed using the Kujala score, Knee injury and Osteoarthritis Outcome Score, and Tegner activity score. Radiological parameters, including patellar height, TT-TG distance, patellar tilt, and congruence angle were compared between the 2 groups. Functional failure based on clinical apprehension sign, repeat subluxation or dislocation, and subjective instability and complications was assessed at the final follow-up. We also compared clinical outcomes based on subgroups of preoperative TT-TG distance (15 mm ≤ TT-TG ≤ 20 mm vs 20 mm < TT-TG ≤ 25 mm).

RESULTS

All of the clinical outcome parameters significantly improved in both groups at the final follow-up (P < .001), with no significant differences between groups. The radiological parameters also showed no significant differences between the 2 groups. The incidence of functional failure was similar between the 2 groups (3 failures in the TTO group and 2 failures in the iMPFL group; P = .42). In the TTO group, 1 patient experienced a repeat dislocation postoperatively and 2 patients had subjective instability; in the iMPFL group, 2 patients had subjective instability. The prevalence of complications did not differ between the 2 groups (P = .410). In the subgroup analysis based on TT-TG distance, we did not note any differences in clinical outcomes between iMPFL and TTO groups in subgroups of 15 mm ≤ TT-TG ≤ 20 mm and 20 mm < TT-TG ≤ 25 mm.

CONCLUSION

MPFL reconstruction with and without TTO provided similar, satisfactory clinical outcomes and low redislocation rates for patients who had patellar instability with a TT-TG distance of 15 to 25 mm, without statistical difference. Thus, our findings suggest that iMPFL reconstruction is a safe and reliable treatment for patients with recurrent patellar dislocation with a TT-TG distance of 15 to 25 mm, without the disadvantages derived from TTO.

Patellar Fixation With Suspensory Fixation Device in Single-Tunnel Medial Patellofemoral Ligament Reconstruction

The medial patellofemoral ligament (MPFL) is the primary soft-tissue stabilizer of the patellofemoral joint. Among the patellofemoral instability surgery options, MPFL reconstruction is the most preferred soft-tissue procedure. There is no gold-standard surgical treatment method in MPFL reconstruction, and many surgical methods have been described. We describe our surgical technique for MPFL reconstruction wherein the semitendinosus autograft is fixed to a single tunnel opened in the patella with a suspensory fixation device and only a single interference screw on the femoral side.

Comparison of Clinical and Radiological Outcomes Between Transosseous Tunnel and Suture Anchor Patellar Fixation for Medial Patellofemoral Ligament Reconstruction: A Cohort Study With 2-Year Follow-up

BACKGROUND

Several surgical methods have been developed for medial patellofemoral ligament reconstruction (MPFLR). However, the question of which patellar fixation method, suture anchor (SA) or transosseous tunnel (TO) fixation, achieves better overall outcomes remains to be answered.

HYPOTHESIS

SA patellar fixation will present comparable clinical outcomes and a lower complication rate compared with TO patellar fixation for MPFLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

We retrospectively reviewed the outcomes of 46 patients who underwent MPFLR with either TO fixation (n = 21; mean age, 24.4 ± 6.1 years) or SA fixation (n = 25; mean age, 24.1 ± 12.1 years) for the treatment of recurrent patellar dislocation. Clinical findings (International Knee Documentation Committee [IKDC] subjective score, Lysholm score, and Tegner activity score), radiological findings (congruence angle and patellar tilt angle), and complications (redislocation, patellar fracture, patellofemoral osteoarthritis progression, infection, and stiffness) were compared between the TO and SA groups at the 2-year follow-up visit.

RESULTS

The mean postoperative IKDC subjective and Lysholm scores did not differ significantly between groups. However, postoperative Tegner activity scores were significantly higher in the TO group than in the SA group (TO, 5.8 ± 1.4; SA, 4.9 ± 1.2; P = .012). Congruence angle did not differ significantly between the groups (TO, -3.2 ± 22.8; SA, -7.6 ± 17.8; P = .464). Patellar tilt angle was lower in the TO group than in the SA group (TO, 10.5 ± 5.4; SA, 13.7 ± 2.8; P = .015). During the follow-up period, the TO group had 1 redislocation and 2 patellar fractures, whereas the SA group had no redislocations or fractures. Patellofemoral osteoarthritis progression was significantly higher in the TO group than in the SA group at the 2-year follow-up visit (TO, 9/21; SA, 2/25; P = .006).

CONCLUSION

Both TO and SA patellar fixation methods for MPFLR showed improved clinical outcomes. When compared with TO fixation, SA fixation presented comparable clinical outcomes and a lower complication rate.