High failure rate 10.8 years after vastus medialis transfer and lateral release (Green's quadricepsplasty) for recurrent dislocation of the patella

4-in-1 Quadricepsplasty for Habitual and Fixed Lateral Patellar Dislocation in Children

BACKGROUND

Habitual and fixed patellar dislocations represent extreme forms of patellar instability and can lead to significant functional loss. The underlying complex pathoanatomy of a laterally positioned and shortened extensor mechanism poses challenges in its management. The purpose of our study was to evaluate the anatomic risk factors and outcomes of a 4-in-1 quadricepsplasty (wide lateral releases, Insall proximal tube realignment, Roux-Goldthwait patellar tendon hemi-transfer, and step-wise quadriceps lengthening) for stabilization of habitual and fixed patellar dislocation.

METHODS

In a retrospective study, all patients with habitual and fixed patellar dislocation who underwent 4-in-1 quadricepsplasty and had a minimum 2-year follow-up were identified. Preoperative magnetic resonance imagings were evaluated for the presence of anatomic risk factors. As a prospective part of the study, patient-reported outcomes were collected using validated instruments including Pedi-IKDC, HSS-Pedi FABS activity score, BPII 2.0 score, Kujala score, and KOOS score.

RESULTS

Seventeen knees (12 patients) formed the study cohort. Twelve knees had habitual dislocation (9 in extension and 4 in flexion) and 5 had fixed dislocation. Mean age was 9 years. 6/17 (35.3%) knees were associated with syndromes. On magnetic resonance imaging, trochlear dysplasia was the most common anatomic risk factor present in 15/17 (88.2%) knees. 13/17 (76%) knees had presence of 2 or more risk factors. At the mean follow-up of 43.3 months, the mean Pedi-IKDC score was 88.1, the HSS-Pedi FABS activity score was 15.6, the BPII 2.0 score was 78.2, the Kujala score was 90, KOOS score was 93.9, and overall patient satisfaction score was 83.3. For complications, 3/17 knees (17.6%) had recurrent patellar instability, 1 knee had postoperative stiffness that required manipulation under anesthesia and 1 knee had a superficial wound infection.

CONCLUSIONS

Most patients with habitual and fixed patellar dislocation present during the first decade of life. There are several underlying anatomic risk factors, the most common being trochlear dysplasia and patellar tilt. The 4-in-1 quadricepsplasty technique provides reliable patellar stabilization, satisfactory clinical results, and acceptable patient-reported outcomes at a minimum 2-year follow-up, with a 17.6% redislocation rate.

LEVEL OF EVIDENCE

Level IV.

Return to sports and short-term follow-up of 101 cases of medial patellofemoral ligament reconstruction using gracilis tendon autograft in children and adolescents

INTRODUCTION

An acute patellofemoral dislocation is the most common acute knee injury in children. Recent studies suggest up to 40% of immature patients may develop recurrent instability. MPFL reconstruction has become a mainstay for the treatment of patellofemoral instability. Aim of the recent study is to show our experiences of MPFL reconstruction in patellar instability in immature patients using a gracilis autograft in respect to return to sport, growth plate disorders and short-term results.

MATERIALS AND METHODS

A total of 101 patients (50 females, 51 males) were included in this retrospective study. Mean age at time of operation was 14.8 ± 1.6 years. Primary outcome measures included patient satisfaction, Kujala score, recurrent instability, return to normal activity, return to sports, clinical leg axis and complications. Mann-Whitney U test was used for statistical analysis and alpha was set at p < 0.05 to declare significance.

RESULTS

At a mean follow-up of 32.0 ± 12.1 months 90/101 patients could be followed-up. 84% of all patients were satisfied or very satisfied with the result at latest follow-up. 86.6% of all patients were able to return to sports, 2.3% had a relevant deviation of the clinical leg axis, but symmetrical. In sum complication rate was 2.9%. Redislocation rate was 0.9% (1/101). Kujala Score improved significantly from 47.1 preoperatively to 85.3 postoperatively (p < 0.01).

CONCLUSION

Anatomic MPFL reconstruction using gracilis tendon allograft tissue is a safe procedure in children and adolescents with low risk of recurrent instability.

Modified Langenskiöld procedure for congenital patella dislocations in pediatric patients

Background

Great difficulty and more failures were the descriptions of the treatment of congenital patella dislocation in pediatric patients. This study aims to evaluate the outcomes of patients with congenital patellar dislocations treated with the modified Langenskiöld procedure.

Methods

The medical records of 16 knees in 11 patients with a diagnosis of congenital patella dislocation were collected from September 2016 to March 2019. They were treated with the modified Langenskiöld procedure. The mean follow-up period was 37.8 months. The outcome measures were the Lysholm score, Kujala score, patellar stability, and knee range of motion.

Results

Eleven patients, namely, eight girls and three boys, with 16 knees were enrolled. The mean age at the time of operation was 3.1 years. The post-operative mean Lysholm score was 94.8 (SD 5.1; 87–100), whereas the Kujala score was 95 (SD 5.9; 86–100). There were no recurrent dislocations, and all patients had full extension postoperatively.

Conclusion

The modified Langenskiöld procedure is a promising solution for the treatment of congenital patella dislocations.

Level of evidence

Level IV; Case Series; Treatment Study.

A Prospective Cohort Study on Quality of Life among the Pediatric Population after Surgery for Recurrent Patellar Dislocation

Patellofemoral instability is a frequent cause of knee pathology affecting quality of life among the pediatric population. Here, we present a prospective cohort study which included patients who had undergone surgical management using the lateral release and medial imbrication approach (LRMI) or medial patellofemoral ligament reconstruction (MPFL-R). The object of this study was to assess the quality of life among children that have undergone surgical treatment for patellar dislocation. Quality of life was assessed before and after surgery using the Pediatric International Knee Documentation Committee form (Pedi-IKDC), a questionnaire that aims to quantify knee functionality. Postoperative scarring was evaluated using The Stony Brook Scar Evaluation Scale. One hundred and eight patients were selected and grouped according to the type of procedure. Before surgery, the two groups had similar mean Pedi-IKDC scores (41,4 MPFL-R vs. 39,4 LRMI p = 0.314). Improvements were observed in the postoperative scores. The MPFL-R technique showed promising outcomes. When comparing the two surgical groups, there was a significant difference in favor of MPFL-R group (MPFL-R 77.71 points vs. LRMI 59.74 points, p < 0.0001-95% CI (11.22-24.72)). Using the Stony Brook Scar Evaluation Scale, a significant difference in scar quality in favor of MPFL-R was observed (4,5 MPFL-R vs. 2,77 LRMI p = 0.002). In conclusion, this study provides objective evidence-based outcome assessments that support the medial patellofemoral ligament reconstruction technique as the gold standard for patellofemoral instability.

Femoral derotation osteotomy for recurrent patellar dislocation

PURPOSE

Excessive femoral internal torsion is an important risk factor for patellar dislocation. The aim of the present study was to estimate the effect of derotational osteotomy of the femur on the tibial tubercle trochlear groove (TTTG) distance or patellar tilt angle (PTA) and to report our clinical outcomes of recurrent patellar dislocation after femoral derotation osteotomy.

METHODS

A retrospective analysis of 16 patients (17 knees) with recurrent patellar dislocation treated by femoral derotation osteotomy in our department from January 2016 to February 2019 was carried out. The procedure was performed with supracondylar femoral derotation. A few procedures were combined with soft tissue procedures. Knee function was evaluated by using the International Knee Documentation Committee (IKDC) score, Kujala score, Lysholm score, visual analog scale (VAS) score and patient satisfaction. Additionally, CT was used to assess the influence of femoral derotational osteotomy on TTTG distance and PTA.

RESULTS

The average femoral antetorsion angle before surgery was 33° (SD ± 5°), and the intraoperative correction angle was 23° (SD ± 4°). A total of 17 femoral derotation osteotomies in 16 patients with patellar instability [11 females, 5 males, aged 20.8 (range 15-41) years] were included in the study. No dislocation occurred within 26.5 months after follow-up (range 12-49 months). The IKDC score, Kujala score, Lysholm score and VAS score significantly improved. The preoperative TTTG distance was 15.63 mm (SD ± 2.07 mm), and it was 14.69 mm (SD ± 1.78 mm) at the follow-up. The PTA decreased from 26.35° (SD ± 6.86°) to 11.65° (SD ± 2.85°). The powers of TTTG and PTA measurements are 0.78 and 1.00, respectively and all of these differences were statistically significant.

CONCLUSIONS

Derotational osteotomy of the femur for the treatment of recurrent patellar dislocation can achieve good clinical results, including improved TTTG distance and PTA and improved knee function.

Modified Langenskiöld procedure for chronic, recurrent, and congenital patellar dislocation

PURPOSE

Langenskiöld described a reconstructive soft-tissue procedure for irreducible lateral congenital patellar dislocations. Paley further detailed the technique in the surgical management of congenital femoral deficiency. The aim of this study was to evaluate the outcomes of patients with congenital, chronic and recurrent patellar dislocations treated with the modified Langenskiöld procedure.

METHODS

This is a retrospective case series. Between 2011 and 2018, 18 knees in 13 patients (mean age 15.8 years (sd 4.4; 12 to 29.9), nine female) with diagnoses of recurrent (six patients, eight knees), chronic (four patients, six knees) and congenital (three patients, four knees) patellar dislocations were treated with the modified Langenskiöld procedure.

RESULTS

There were no recurrent lateral dislocations in the congenital or recurrent groups. One of the patients in the congenital group had an overcorrection with some medial patellar maltracking but until this time has not required any further surgery. In the chronic group two of the six knees developed further dislocations; these were both on the same patient, who had no dislocations until one year after surgery. Mean Kujala score was 83.7 (sd 17; 47 to 100) for all groups. In spite of preoperative knee flexion contractures of up to 30° in three patients (six knees), all patients had full extension postoperatively. Eight patients reported being satisfied with their outcome, one was somewhat satisfied, two were very dissatisfied, and two did not respond.

CONCLUSION

The modified Langenskiöld reconstruction provides a powerful correction for challenging cases of congenital and recurrent patellar dislocations. Re-dislocation as well as overcorrection can occasionally occur.

LEVEL OF EVIDENCE

Level IV.