A systematic review and meta-analysis comparing conservative and surgical treatments for acute patellar dislocation in children and adolescents

Techniques for surgical stabilization of the patella in children

Patellar instability can be defined as dislocation or subluxation of the patella relative to the femoral trochlea. It is a common reason for consulting a pediatric orthopedic surgeon. Its etiology is multifactorial. Because of the work of Hughston, Merchant, Ficat, Insall and Dejour, the overall care of this pathology has changed greatly. Surgical stabilization of the patella in children is being performed more often due to better understanding of the pathology and widespread adoption of reconstruction techniques for the medial patellofemoral ligament. However, some surgical techniques should not be used in children. Determining the type of instability is the first step to selecting the appropriate technique and to avoiding the biggest pitfall - recurrence. LEVEL OF EVIDENCE: Expert opinion.

Combined Medial Patellofemoral Ligament and Medial Quadriceps Tendon Femoral Ligament Reconstruction With Semitendinosus Allograft for Pediatric Patients With First-Time Patella Dislocation Yields Low Failure Rates and Improved Functional Outcomes Compared With Nonoperative Treatment

PURPOSE

To evaluate the clinical outcomes of nonoperative versus operative treatment, consisting of combined medial patellofemoral ligament and medial quadriceps tendon femoral ligament (MPFL/MQTFL) reconstruction, for first-time patellar dislocation in the skeletally immature population through a standardized, rigorous approach.

METHODS

This consecutive retrospective cohort was composed of all skeletally immature patients who sustained a first-time patellofemoral dislocation. Patients were grouped into nonoperative management (bracing and physical therapy) and operative management (MPFL/MQTFL reconstruction) cohorts. The primary outcome, failure, was defined as subsequent dislocation or subluxation. Additional outcomes included demographics, risk factors for patellofemoral instability, functional outcomes (Kujala and Pediatric International Knee Documentation Committee scores), return to sports, and complications. Minimum follow-up was 2 years. A correlation analysis attempted to identify potential associations between failure and risk factors.

RESULTS

In total, 142 consecutive patients were included with 90 patients in the nonoperative group and 52 patients in the operative group. Failure rates differed by intervention; those receiving operative management had significantly lower failure rates than conservative management (15.4% vs 58.8%, P < .0001). Kujala and Pediatric International Knee Documentation Committee scores were significantly greater in the operative group compared with the nonoperative group (91.5 ± 7.8 vs 82.5 ± 12.1, P < .0001 and 89.0 ± 9.3 vs 78.4 ± 12.9, P < .0001, respectively). Tegner activity level was also greater in the operative group (6.0 ± 1.4 vs 4.0 ± 1.4, P < .0001). Return to sport was significantly greater for those in the operative group (88.5% vs 66.2%, P < .001). Return to same level of activity was achieved in greater percentage of patients treated surgically (91.3% vs 69.6%, P = .0075). Complication rates were more frequent in the operative group compared with the nonoperative group (11.5% vs 1.1%, P < .001).

CONCLUSIONS

MPFL/MQTFL reconstruction in skeletally immature patients with first-time patellofemoral dislocation demonstrated lower failure rates and improved functional outcomes at a minimum 2-year follow-up compared with nonoperative management.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Age Is a Key Factor Influencing the Choice of Treatment for Primary Patellar Dislocation: A Systematic Review and Meta-analysis

Primary patellar dislocation has a certain recurrence rate after either conservative or surgical treatment, and the optimal treatment for patients with primary patellar dislocation of different ages remains unclear. This study aims to compare the clinical efficacy of surgical and conservative treatments for primary patellar dislocation across different age groups. According to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist, we conducted a systematic search for randomized controlled trials. We searched the PubMed, EMBASE, Cochrane Library, and Web of Science databases for randomized controlled trials of primary patellar dislocation treated surgically or conservatively up to January 2023. Data searching, extraction, analysis, and quality assessment were carried out in accordance with the Cochrane Collaboration guidelines. A total of nine studies with 433 patients were included in our study. There was no statistically significant difference between the two treatment modalities in terms of Kujala score, pain score, patient satisfaction, reoperation, and Tegner score. The rate of re-dislocation after surgical treatment is lower than that after conservative treatment. Subgroup analysis based on mean age showed that when the age was >20 years, Kujala scores were higher after surgical treatment than after conservative treatment (p < 0.0001, 95% confidence interval [CI] = 10.41-21.30). When the age was ≤20 years, the difference in Kujala scores between the two treatment modalities was not statistically significant. When the age was >20 years, the recurrence rate of patellar dislocation was lower after surgical treatment than after conservative treatment (p = 0.009, 95% CI = 0.08-0.70). When the age was ≤20 years, the difference in the recurrence rate of patellar dislocation between the two treatment modalities was not statistically significant. When the age of patients with primary patellar dislocation is ≤20 years, both surgical and conservative treatments result in similar clinical outcomes. When the age is >20 years, better clinical outcomes can be achieved by opting for surgical treatment. Therefore, surgery may be a better option for patients with primary patellar dislocation whose age is >20 years.

Ellipsoidal patellar bone tunnel fixation with Toggleloc suspension system for medial patellofemoral ligament reconstruction: A 5 years follow-up

BACKGROUND

This study aimed to evaluate the clinical and radiological features of the patella fixation technique using Toggleloc suspension system in a single ellipsoidal blind patellar tunnel during medial patellofemoral ligament (MPFL) reconstruction.

METHODS

This study included 52 patients (25 men, 27 women) who underwent MPFL reconstruction using a semitendinosus tendon graft. The graft was fixed to the ellipsoidal single blind tunnel opened on the medial side of the patella with an endobutton and was fixed to the femoral tunnel by using bioabsorbable screw. Clinical scores (Kujala score, Lysholm score, Tegner activity score and the visual analog scale [VAS] score) were evaluated preoperatively and at the end-follow up. Preoperative and postoperative radiological measurements (trochlea depth, sulcus angle, patellar height, patellar congruence angle, patellar tilt angle and lateral patellofemoral angle) were evaluated with X-ray (Merchant X-ray, anteroposterior and lateral radiography) and computed tomography (CT) of the knee.

RESULTS

Postoperative patellar redislocation or subluxation was not observed in any patient. Patellar congruence angle, patellar tilt angle and lateral patellofemoral angle mean values were found to return to normal values in the postoperative period and the results were statistically significant. Also statistically significant improvement in all clinical scores postoperatively. According to the Insall-Salvati index (ISI) and Caton-Deschamps index (CDI) on lateral radiography of the knee at 30° flexion, patellar height decreased in the postoperative period statistically significant. The CDI was above 1.3 in 17 (%32) of our patients. Thirteen of these values decreased to normal values. No radiological progression of patellofemoral osteoarthritis was observed in all patients at the final follow-up evaluation.

CONCLUSION

In cases of patellofemoral instability, fixation of the tendon graft in blind ellipsoid tunnel using the Toggleloc suspension system provides satisfactory patellar graft fixation strength, significant functional improvement and a low failure rate.

Patho-morphology of patellar instability in children and adolescents: A systematic review and meta-analysis

BACKGROUND

Children and adolescents have the highest incidence of patellar instability among the population. We aimed to identify patho-morphological and epidemiological factors associated with patellar instability, and to identify factors predisposing to recurrence in children and adolescents.

METHODS

Published and unpublished literature databases, conference proceedings and the reference lists of included studies were searched to the 14th of March 2024. Studies were eligible if they compared history characteristics, examination features and radiological parameters between patients with and without instability, or evaluated risk factors for instability recurrence. A random-effects meta-analysis was performed. Included studies were appraised using tools respective of study design.

RESULTS

The evidence was moderate to low in quality. Forty-five studies (including 9000 patients) were eligible. Tibial tubercle - tibial groove (TT-TG) distance (weighted mean difference [WMD] 5.96 mm, 95% Confidence Interval [CI]: 4.94 to 6.99 mm), sulcus angle (WMD: 13.93˚, 95% CI: 9.1˚ to 18.8˚), and Insall-Salvati index (WMD: 0.2, 95% CI: 0.16 to 0.23) were greater in patients with patellar instability. Risk factors for recurrent dislocation included age less than 18 years (Odds ratio [OR]: 2.56, 95% CI: 1.63 to 4.0), skeletal immaturity (OR: 1.79, 95% CI: 1.21 to 2.64) and presence of trochlear dysplasia (OR: 3.37, 95% CI: 1.85 to 6.15).

CONCLUSION

Knowledge of patho-morphological factors associated with patellar instability could help explain its pathophysiological processes, allowing for the design of treatment approaches and the identification of patients at risk.

Comparison of Fixation Methods Between Transosseous Pull-Out Suture and Separate Vertical Wiring for Inferior Pole Fracture of Patella: A Systematic Review and Meta-Analysis

OBJECTIVES

To compare, in a systematic review, Krakow transosseous (KT) suturing and separate vertical wiring (VW) fixation methods in inferior pole fractures of the patella and to evaluate whether the supplementary fixation affected bone union.

METHODS

DATA SOURCES

The MEDLINE, Embase, and Cochrane databases were searched from inception to January 15, 2023. The keywords were "patella inferior pole fracture", "patella distal pole fracture", "transosseous", "pull-out suture", "reattachment", and "vertical wiring".

STUDY SELECTION

All clinical studies describing KT or VW techniques for inferior pole fracture of the patella and reporting bone union-related complications were included.

DATA EXTRACTION

This meta-analysis included 16 studies with 274 patellae. Demographic data, surgical techniques, clinical outcomes, and complication rates were recorded. The Methodological Index for Non-Randomized Studies criteria were used to assess their quality.

DATA SYNTHESIS

A meta-analysis was performed using random-effects models and meta-regression. The meta-analytic estimate of bone union-related complications was 3.8% (95% CI, 1.6%-6.0%) for either PO or VW techniques in inferior pole fractures of the patella. The bone union-related complication rates did not differ significantly between the two techniques (KT, 5.7%; VW, 3.0%; P = .277). Meanwhile, supplementation fixation was significantly associated with decrease in bone union-related complication rates ( p = .013).

CONCLUSIONS

Fixation of inferior pole fractures of the patella using either KT or VW techniques provided satisfactory and similar clinical results with minimal bone union-related complications. Supplementary fixation has a positive impact on reducing bone union-related complications in inferior pole fractures of the patella following KT and VW techniques.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Non-operative Management of Acute Knee Injuries

PURPOSE OF REVIEW

Acute knee injuries are commonly encountered in both the clinical and sideline setting and may be treated operatively or non-operatively. This article describes an evidence-based approach to non-operative acute knee injury. This includes history, physical exam, imaging, and initial management. In addition, the non-operative management of three such injuries-ligament injury, meniscus injury, and patellar dislocation injury-will be discussed via a case-based practical approach.

RECENT FINDINGS

Aside from grade III ACL tears, most acute knee ligament injuries, especially in the absence of other concurrent injuries, can be treated non-operatively. There is new evidence that acute traumatic meniscus tears in those younger than 40 can be successfully treated non-operatively and can do equally, as well as those that undergo surgery, at 1 year out from injury. Based on the current literature, a short period of knee bracing in extension with progression to weightbearing to tolerance is recommended after initial patellar dislocation. Many of the most common acute knee injuries, including MCL tears, meniscus tears, and patellar dislocations, can be managed non-operatively. A detailed systemic approach to initial evaluation, including pertinent history, physical exam, and appropriate imaging, is essential and complementary to the subsequent non-operative treatment algorithm.

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.