Operative versus closed treatment of primary dislocation of the patella. Similar 2-year results in 125 randomized patients

Mid-term outcomes of temporary medial distal femoral hemiepiphysiodesis with and without medial patellofemoral ligament repair for recurrent patellar instability in skeletally immature patients with genu valgum

Genu valgum contributes to patellar instability, though outcomes following temporary hemiepiphysiodesis via eight plating are less understood. The purpose of this study was to evaluate the outcomes and need for additional procedures following temporary hemiepiphysiodesis for the treatment of pediatric genu valgum and patellar instability, as well as evaluating the utility of a concurrent medial patellofemoral ligament (MPFL) repair. Patients who underwent medial distal femoral epiphysiodesis for the treatment of genu valgum and recurrent patellar instability were identified. Inclusion criteria were minimum 1-year follow-up and lack of concurrent ligamentous reconstruction. Patients were contacted to complete a questionnaire which included the International Knee Documentation Committee (IKDC) form and questions pertaining to knee function and patient satisfaction. Thirty-one patients aged 12.0 ± 1.9 years underwent 47 guided growth procedures and were included in final analysis. Seventeen knees (36%) required subsequent surgery for patellar instability. All patients requiring subsequent surgery were female, compared with 70% of patients not requiring subsequent surgery ( P  = 0.017). The MPFL repair group underwent fewer subsequent procedures to address instability, though this difference was NS (17 vs. 46%, P  = 0.318). Mean IKDC score at 5.3 years follow-up among 18 survey respondents was 78.6. Medial distal femoral hemiepiphysiodesis may partially address recurrent patellar instability in skeletally immature patients with genu valgum. Concurrent MPFL repair may minimize the need for subsequent procedures to address recurrent instability. While correcting alignment may be helpful, patients should be aware of the potential need for further patellar instability surgery. Level of evidence: IV, case series.

Operative versus non-operative management of primary patellar dislocation: A systematic review and network meta-analysis

BACKGROUND

Acute patellar dislocation is a common knee injury in adolescents and adults that is associated with a high incidence of medial patellofemoral ligament (MPFL) injuries. The aim of this network meta-analysis was to compare the different operative and non-operative protocols for the management of primary patellar dislocation (PPD).

METHODS

We searched Medline, Embase, and CENTRAL databases. We included randomized controlled trials (RCTs) that compared operative and non-operative protocols for adolescent or adult patients with acute traumatic PPD. We sought to evaluate the clinical and functional outcomes of each management protocol by considering the results of Kujala score, Tegner activity score, redislocation rate, and subluxation rate. The effectiveness of the different management protocols was measured through frequentist network meta-analysis, using the Netmeta statistical package in R software. All treatment protocols were ranked using the netrank function, yielding P scores.

RESULTS

A total of 10 RCTs were deemed eligible. As per P-scores, open MPFL repair yielded the highest effectiveness with respect to Kujala score (P=0.81) and lowest odds for redislocation (P=0.14) whereas arthroscopic MPFL repair yielded the highest effectiveness with respect to Tegner activity score (P=0.85) and lowest odds for subluxation (P=0.21). Arthroscopic MPFL repair showed a significant reduction in redislocation and subluxation rate.

CONCLUSION

This network meta-analysis demonstrated arthroscopic MPFL repair is the most effective treatment protocol for the management of acute primary patellar dislocation.

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.

Medial Patellofemoral Ligament Reconstruction is Preferred to Repair or Reefing for First-Time Patellar Dislocation: A Systematic Review and Meta-analysis

Purpose

The purpose of this systematic review aimed to investigate the clinical outcome of medial patellofemoral ligament (MPFL) reconstruction, MPFL repair and medial reefing for patients with first-time patellar dislocation.

Methods

Databases of PubMed, EMBASE, Cochrane Library and Web of Science were searched up to May 8, 2022. Only articles treating first-time patellar dislocation with MPFL reconstruction, MPFL repair and medial reefing were included in the analysis. Eligible identification, data extraction, quality assessment and statistical analysis were performed by two independent reviewers. The primary outcome measures were the incidences of postoperatively redislocation and reoperation. The second outcomes were the Kujala functional score and complications (including infection, osteoarthritis, and loss of range of motion).

Results

Twenty-two studies involving 668 patients met the inclusion criteria. Of which, four studies involving 126 patients were in MPFL reconstruction group, ten studies involving 220 patients in MPFL repair group and 9 studies involving 322 patients in medial reefing group. Our results showed that the MPFL reconstruction (1.8%, 95% CI - 0.5 to 4.0%) had a significantly lower rate of postoperative redislocation and reoperation rate than the MPFL repair (15.4%, 95% CI 5.2-25.7%) and medial reefing (18.0%, 95% CI 9.3-26.7%). Besides, no significant differences were found in the Kujala score and complication rate among the three treatments.

Conclusion

The available evidence demonstrated that MPFL reconstruction could achieve significantly lower redislocation rate and reoperation rate than MPFL repair and medial reefing after first-time patella dislocation. Furthermore, there was not enough evidence to reveal that MPFL reconstruction provided better functional outcome compared with MPFL repair and medial reefing. MPFL reconstruction is a preferred surgical treatment for patients with first-time patellar dislocation.

Level of Evidence

Level IV, systematic review of Level I-IV.

Surgical versus non-surgical interventions for treating patellar dislocation

BACKGROUND

Patellar (knee cap) dislocation occurs when the patella disengages completely from the trochlear (femoral) groove. It affects up to 42/100,000 people, and is most prevalent in those aged 20 to 30 years old. It is uncertain whether surgical or non-surgical treatment is the best approach. This is important as recurrent dislocation occurs in up to 40% of people who experience a first time (primary) dislocation. This can reduce quality of life and as a result people have to modify their lifestyle. This review is needed to determine whether surgical or non-surgical treatment should be offered to people after patellar dislocation.

OBJECTIVES

To assess the effects (benefits and harms) of surgical versus non-surgical interventions for treating people with primary or recurrent patellar dislocation.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, AMED, CINAHL, Physiotherapy Evidence Database and trial registries in December 2021. We contacted corresponding authors to identify additional studies.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled clinical trials evaluating surgical versus non-surgical interventions for treating primary or recurrent lateral patellar dislocation in adults or children.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were recurrent patellar dislocation, and patient-rated knee and physical function scores. Our secondary outcomes were health-related quality of life, return to former activities, knee pain during activity or at rest, adverse events, patient-reported satisfaction, patient-reported knee instability symptoms and subsequent requirement for knee surgery. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included 10 studies (eight randomised controlled trials (RCTs) and two quasi-RCTs) of 519 participants with patellar dislocation. The mean ages in the individual studies ranged from 13.0 to 27.2 years. Four studies included children, mainly adolescents, as well as adults; two only recruited children. Study follow-up ranged from one to 14 years. We are unsure of the evidence for all outcomes in this review because we judged the certainty of the evidence to be very low. We downgraded each outcome by three levels. Reasons included imprecision (when fewer than 100 events were reported or the confidence interval (CI) indicated appreciable benefits as well as harms), risk of bias (when studies were at high risk of performance, detection and attrition bias), and inconsistency (in the event that pooled analysis included high levels of statistical heterogeneity). We are uncertain whether surgery lowers the risk of recurrent dislocation following primary patellar dislocation compared with non-surgical management at two to nine year follow-up. Based on an illustrative risk of recurrent dislocation in 348 people per 1000 in the non-surgical group, we found that 157 fewer people per 1000 (95% CI 209 fewer to 87 fewer) had recurrent dislocation between two and nine years after surgery (8 studies, 438 participants). We are uncertain whether surgery improves patient-rated knee and function scores. Studies measured this outcome using different scales (the Tegner activity scale, Knee Injury and Osteoarthritis Outcome Score, Lysholm, Kujala Patellofemoral Disorders score and Hughston visual analogue scale). The most frequently reported score was the Kujala Patellofemoral Disorders score. This indicated people in the surgical group had a mean score of 5.73 points higher at two to nine year follow-up (95% CI 2.91 lower to 14.37 higher; 7 studies, 401 participants). On this 100-point scale, higher scores indicate better function, and a change score of 10 points is considered to be clinically meaningful; therefore, this CI includes a possible meaningful improvement. We are uncertain whether surgery increases the risk of adverse events. Based on an assumed risk of overall incidence of complications during the first two years in 277 people out of 1000 in the non-surgical group, 335 more people per 1000 (95% CI 75 fewer to 723 more) had an adverse event in the surgery group (2 studies, 144 participants). Three studies (176 participants) assessed participant satisfaction at two to nine year follow-up, reporting little difference between groups. Based on an assumed risk of 763 per 1000 non-surgical participants reporting excellent or good outcomes, seven more participants per 1000 (95% CI 199 fewer to 237 more) reported excellent or good satisfaction. Four studies (256 participants) assessed recurrent patellar subluxation at two to nine year follow-up. Based on an assumed risk of patellar subluxation in 292 out of 1000 in the non-surgical group, 73 fewer people per 1000 (95% CI 146 fewer to 35 more) had patellar subluxation as a result of surgery. Slightly more people had subsequent surgery in the non-surgical group. Pooled two to nine year follow-up data from three trials (195 participants) indicated that, based on an assumed risk of subsequent surgery in 215 people per 1000 in the non-surgical group, 118 fewer people per 1000 (95% CI 200 fewer to 372 more) had subsequent surgery after primary surgery.

AUTHORS' CONCLUSIONS

We are uncertain whether surgery improves outcome compared to non-surgical management as the certainty of the evidence was very low. No sufficiently powered trial has examined people with recurrent patellar dislocation. Adequately powered, multicentre, randomised trials are needed. To inform the design and conduct of these trials, expert consensus should be achieved on the minimal description of both surgical and non-surgical interventions, and the pathological variations that may be relevant to both choice of these interventions.

MPFL repair after acute first-time patellar dislocation results in lower redislocation rates and less knee pain compared to rehabilitation: a systematic review and meta-analysis

PURPOSE

This study aimed to explore the efficacy of medial patellofemoral ligament (MPFL) repair versus nonoperative rehabilitation treatment on the rate of patellar redislocation and functional outcomes in skeletally mature patients with traumatic, first-time patellar dislocations.

MATERIALS AND METHODS

MEDLINE, PubMed and EMBASE were searched from database inception to May 2022 for studies examining the management options for acute first-time patellar dislocations. This study was conducted in accordance with PRISMA and R-AMSTAR guidelines. Data on redislocation rates, functional outcomes including the Kujala score for anterior knee pain, and complication rates were extracted. A meta-analysis was used to pool the mean postoperative Kujala score and calculate the proportion of patients sustaining redislocations using a random effects model. Quality assessment of included studies was performed for all included studies using the MINORS and Detsky scores.

RESULTS

This review included a total of 25 studies and 1,361 patients. The pooled mean redislocation rate in 15 studies comprising 798 patients in the rehabilitation group was 30% (95% CI 25-36%, I² = 65%). Moreover, the pooled mean redislocation rate in 10 studies comprising 170 patients undergoing MPFL repair was 7% (95% CI 3-12%, I² = 30%). The pooled mean postoperative Kujala score in 8 studies comprising 396 patients in the rehabilitation group was 82.5 (95% CI 78.3-86.8, I² = 91%), compared to a score of 88 (95% CI 87-90, I² = 76%) in 3 studies comprising 94 patients in the repair group. Range of motion deficits was reported in 3.8% of 893 patients in the rehabilitation group and 2.0% of 205 patients in the repair group.

CONCLUSION

MPFL repair resulted in a lower rate of redislocation, less knee pain, and noninferiority with respect to a range of motion deficits compared to nonoperative treatment for the management of acute first-time patellar dislocations.

LEVEL OF EVIDENCE

IV.

Return to Play Considerations After Patellar Instability

PURPOSE OF REVIEW

To discuss the treatment options and rehabilitation protocols after non-operative and operative treatment of patellar instability, and to discuss expected return to play outcomes and functional performance with non-operative and operative treatment of patellar instability.

RECENT FINDINGS

A criterion-based program assessing range of motion, joint effusion, strength, neuromuscular control, proprioception, agility, and power are critical measures to assess when rehabilitating this population. A series of functional tests including quadriceps strength testing, single-limb hop testing, lateral step-down test, the side hop test, the lateral leap and catch test, the Y-balance test, and the depth jump should be considered when determining an athlete's return to sport clearance. These objective measures combined with psychological readiness and a comprehensive understanding of the sports-specific tasks required for participation should be considered when evaluating an athlete's ability to safely and successfully return to sport. We discuss rehabilitation management when working with non-operative and operative management of patellar instability and provide considerations for clinicians working with these athletes to facilitate safe return to sport.

MPFL reconstruction results in lower redislocation rates and higher functional outcomes than rehabilitation: a systematic review and meta-analysis

PURPOSE

To determine the effect of early MPFL reconstruction versus rehabilitation on the rate of recurrent patellar dislocations and functional outcomes in skeletally mature patients with traumatic, first-time patellar dislocation.

METHODS

Three online databases MEDLINE, PubMed and EMBASE were searched from database inception (1946, 1966, and 1974, respectively) to August 20th, 2021 for literature addressing the management of patients sustaining acute first-time patellar dislocations. Data on redislocation rates, functional outcomes using the Kujala score, and complication rates were recorded. A meta-analysis was used to pool the mean postoperative Kujala score, as well as calculate the proportion of patients sustaining redislocation episodes using a random effects model. Quality assessment of included studies was performed for all included studies using the MINORS and Detsky scores.

RESULTS

A total of 19 studies and 1,165 patients were included in this review. The pooled mean redislocation rate in 14 studies comprising 734 patients in the rehabilitation group was 30% (95% CI 25-36%, I² = 67%). Moreover, the pooled mean redislocation rate in 5 studies comprising 318 patients undergoing early MPFL reconstruction was 7% (95% CI 2-17%, I² = 70%). The pooled mean postoperative Kujala anterior knee pain score in 7 studies comprising 332 patients in the rehabilitation group was 81 (95% CI 78-85, I² = 78%), compared to a score of 87 (95% CI 85-89, I² = 0%, Fig. 4) in 3 studies comprising 54 patients in the reconstruction group.

CONCLUSION

Management of acute first-time patellar dislocations with MPFL reconstruction resulted in a lower rate of redislocation of 7% in the reconstruction group vs 30% in the rehabilitation group and a higher Kujala score compared to the rehabilitation group. The information this review provides will help surgeons guide their decision to choose early MPFL reconstruction versus rehabilitation when treating patients with first-time patellar dislocations and may guide future studies on the topic.

LEVEL OF EVIDENCE

IV.

Medial Plication Using an Arthroscopic All-Inside Technique for Treatment of Patellar Instability in Adolescents

The purpose of this study was to present a medial plication using an arthroscopic all-inside technique for the treatment of patellar instability in adolescents. From July 2009 to June 2012, 19 patients with acute patellar dislocation were operated by this technique. Of these patients, follow-up was available in 17 patients at an average of 3 years (range: 1.5-4 years). At the follow-up, we evaluated the patients with physical examinations, radiographs, computed tomography scan, as well as the Lysholm and Kujala scoring scales. No recurrence of patellar instability has been found. The recovery of knee mobilization resulted to be good. We think this could be a valid technique to treat patellar instability in adolescents with less associated morbidity and good cosmetic results.

Benefits and Harms of Interventions With Surgery Compared to Interventions Without Surgery for Musculoskeletal Conditions: A Systematic Review With Meta-analysis

OBJECTIVE

To estimate the benefits and harms of interventions with and without surgery for musculoskeletal (MSK) conditions.

DESIGN

Intervention systematic review with meta-analysis of randomized controlled trials (RCTs).

LITERATURE SEARCH

MEDLINE, EMBASE, CINAHL, Web of Science, and CENTRAL, all up to January 7, 2021.

STUDY SELECTION CRITERIA

RCTs (English, German, Danish, Swedish, and Norwegian) of interventions with and without surgery conducted in any setting for any non-fracture MSK condition in adults (mean age: 18+ years) evaluating the outcomes on a continuous (benefits) or count (harms) scale. Outcomes were pain, self-reported physical function, quality of life, serious adverse events (SAEs), and death at 1 year.

DATA SYNTHESIS

Random-effects metaanalyses for MSK conditions where there were data from at least 2 trials.

RESULTS

One hundred RCTs (n = 12 645 patients) across 28 different conditions at 9 body sites were included. For 9 out of 13 conditions with data on pain (exceptions include some spine conditions), 11 out of 11 for function, and 9 out of 9 for quality of life, there were no clinically relevant differences (standardized mean difference of 0.50 or above) between interventions with and without surgery. For 13 out of 16 conditions with data on SAEs and 16 out of 16 for death, there were no differences in harms. Only 6 trials were at low risk of bias.

CONCLUSION

The low certainty of evidence does not support recommending surgery over nonsurgical alternatives for most MSK conditions with available RCTs. Further high-quality RCTs may change this conclusion. J Orthop Sports Phys Ther 2022;52(6):312-344. doi:10.2519/jospt.2022.11075.

Comparing Nonoperative Treatment, MPFL Repair, and MPFL Reconstruction for Patients With Patellar Dislocation: A Systematic Review and Network Meta-analysis

Background:

Medial patellofemoral ligament (MPFL) reconstruction, MPFL repair, and nonoperative treatment are important treatments for patients with patellar dislocation. However, it is unclear which treatment leads to better outcomes.

Purpose:

To determine the efficacy and safety of the 3 treatments in the treatment of patellar dislocation and compare the effect of MPFL reconstruction with MPFL repair, MPFL reconstruction with nonoperative treatment, and MPFL repair with nonoperative treatment.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

The PubMed, Web of Science, Cochrane Library, Embase, CNKI (China National Knowledge Infrastructure), and Wanfang databases were searched from inception to December 2020. Included were clinical studies that described the efficacy and safety of 2 of the 3 treatments, studies directly comparing the clinical effects of the 2 operative techniques, or studies comparing the effects of reconstruction or repair with nonoperative treatment. Two reviewers independently extracted data and assessed the quality of the included studies with the Cochrane risk-of-bias tools. The outcomes evaluated were postoperative redislocation rate, revision rate, complications, and Kujala score. We used traditional direct pairwise meta-analysis as well as network meta-analysis for comprehensive efficacy of all 3 treatment measures.

Results:

Twelve studies were included: 5 compared MPFL reconstruction with MPFL repair, 2 compared MPFL reconstruction with nonoperative treatment, and 5 compared MPFL repair with nonoperative treatment. The risk of bias was serious in 4, moderate in 4 and low in 4 articles. MPFL reconstruction led to significantly reduced redislocation and improved Kujala scores compared with MPFL repair and nonoperative treatment. MPFL repair led to reduced redislocation rates compared with nonoperative treatment but did not show an obvious benefit in primary dislocations. There was no significant difference among the 3 treatments in terms of revision rate and incidence of complications, although we found that treatment-related complications were least likely to occur in nonoperative treatment.

Conclusion:

The results of this review indicate that MPFL reconstruction decreases recurrent dislocation compared with MPFL repair or nonoperative treatment, but it has a higher possibility of complications. MPFL repair resulted in less postoperative redislocation than nonoperative treatment but did not show an obvious benefit in primary dislocation.

Online Rehabilitation Protocols for Medial Patellofemoral Ligament Reconstruction With and Without Tibial Tubercle Osteotomy Are Variable Among Institutions

Purpose

To compare and contrast the various rehabilitation protocols for medial patellofemoral ligament (MPFL) reconstruction and MPFL reconstruction plus tibial tubercle osteotomy (TTO) published online by academic orthopaedic surgery residency programs and private practice institutions throughout the United States.

Methods

We performed a systematic electronic search of MPFL reconstruction rehabilitation protocols in academic orthopaedic surgery residency programs in the United States using Google’s search engine (www.google.com) based on the Fellowship and Residency Electronic Interactive Database Access System (FREIDA). Private practice organizations publishing MPFL reconstruction or MPFL reconstruction–TTO rehabilitation protocols that were found on the first page of search results were also included, but no comprehensive search for private practice protocols was performed. Protocols specifying an MPFL reconstruction with TTO were included for separate review because of altered weight-bearing status postoperatively. A list of comparative criteria was created to assess the protocols for the presence and timing of the various rehabilitation components.

Results

From the list of 189 U.S. academic residency programs, as well as additional private practice protocols found in the Google search, 38 protocols were included for review (31 protocols for isolated MPFL reconstruction and 7 protocols for MPFL reconstruction plus TTO). A return to full range of motion by week 6 was recommended by 15 (48.4%) of the isolated MPFL reconstruction protocols and 6 (85.7%) of the MPFL reconstruction–TTO protocols. Six weeks of knee brace wear was recommended by 13 isolated MPFL reconstruction protocols (43.3%) and 4 MPFL reconstruction–TTO protocols (57.1%). Moreover, 6 isolated MPFL reconstruction protocols (19.4%) and 3 MPFL reconstruction–TTO protocols (42.9%) recommended use of a patellar stabilizing brace postoperatively.

Conclusions

There is substantial variability among rehabilitation protocols after MPFL reconstruction, as well as MPFL reconstruction plus TTO, including postoperative range of motion, weight-bearing status, and time until return to sport. Furthermore, many online protocols from academic orthopaedic surgery residency programs and private practices in the United States fail to mention several of these parameters, most notably functional testing to allow patients to return to sport.

Clinical Relevance

Proper rehabilitation after MPFL reconstruction with or without TTO is an important factor to a patient’s postoperative outcome. This study outlines the variability in online rehabilitation protocols after MPFL reconstruction with or without TTO published online by academic residency programs and private practice institutions.

Initial conservative treatment of osteochondral fracture of the patella following first-time patellar dislocation

Background

There has been no gold standard of the initial treatment strategy for acute patellar dislocation (APD) with osteochondral fracture (OCF). Hence the study aim is firstly, to review and compare clinical outcomes of patients who underwent conservative treatment for APD with or without OCF. Secondly, to characterize the location and size of fracture fragment.

Methods

Sixty-nine consecutive patients who were retrospectively evaluated after first-time APD over a 2- year period were divided into two groups (group 1 (n = 24): APD with OCF and group 2 (n = 45): APD only). Magnetic resonance imaging (MRI) was used to assess patients with APD and OCF from the medial patella. All patients were treated with a supervised course of immobilization followed by progressive range of motion and strength exercise protocol. History of a recurrent dislocation, radiologic and functional scores were analyzed.

Results

Redislocation rate was 31.2% in group 1 and 26.6% in group 2, showing no significant difference between the two groups (p = 0.690). Intergroup differences in terms of final Kujala and IKDC scores were not significant (p = 0.117 and p = 0.283, respectively). Fracture sites of the patella in group 1 were classified as follows: patellar medial margin (12), inferomedial facet (7), and inferomedial facet involving central ridge (5). In the subgroup of patient with OCF of the inferomedial facet of the patella, the fragments were found in the lateral gutter and did not cause pain or mechanical symptoms. Thus, loose body removal was not performed. However, all five patients with large OCF involving the central ridge of the patella failed non-operative treatment with recurrent dislocations, ultimately requiring fragment refixation and medial retinacular imbrication.

Conclusions

First, APD patients with OCFs of medial margin or inferomedial facet showed similar redislocation rates and functional knee scores with those without OCFs after conservative treatment. Second, initial conservative treatment failed in some APD patients with large OCF, especially when OCFs were fractured from inferomedial facet involving central ridge. Surgery should be considered with this type.

Conservative Versus Surgical Treatment for Primary Patellar Dislocation

BACKGROUND

Primary patellar dislocation is often the initial manifestation of patellofemoral instability. Its long-term consequences can include recurrent dislocation and permanent dysfunction of the knee joint. There is no consensus on the optimal treatment of primary patellar dislocation in the relevant literature. The main prerequisite for a good long-term result is a realistic assessment of the risk of recurrent dislocation.

METHODS

We carried out a systematic literature search in OvidSP (a search engine for full-text databases) and MEDLINE to identify suitable stratification models with respect to the risk of recurrent dislocation.

RESULTS

In the ten studies included in the current analysis, eight risk factors for recurrence after primary patellar dislocation were identified. Six studies revealed a higher risk in younger patients, particularly those under 16 years of age. The sex of the patient had no clear influence. In two studies, bilateral instability was identified as a risk factor. Two anatomical risk factors-a high-riding patella (patella alta) and trochlear dysplasia-were found to have the greatest influence in six studies. In a metaanalysis of five studies, patella alta predisposed to recurrent dislocation with an odds ratio (OR) of 4.259 (95% confidence interval [1.9; 9.188]). Moreover, a pathologically increased tibial tuberosity to trochlear groove (TT-TG) distance and rupture of the medial patellofemoral ligament (MPFL) on the femoral side were associated with higher recurrence rates. Patients with multiple risk factors in combination had a very high risk of recurrence.

CONCLUSION

The risk of recurrent dislocation after primary patellar dislocation is increased by a number of risk factors, and even more so when multiple such risk factors are present. Published stratification models enable an assessment of the individual risk profile. Patients at low risk can be managed conservatively; surgery should be considered for patients at high risk.

The feasibility of a randomised control trial to assess physiotherapy against surgery for recurrent patellar instability

Background

Patellar instability is a relatively common condition that leads to disability and restriction of activities. People with recurrent instability may be given the option of physiotherapy or surgery though this is largely driven by clinician preference rather than by a strong evidence base. We sought to determine the feasibility of conducting a definitive trial comparing physiotherapy with surgical treatment for people with recurrent patellar instability.

Methods

This was a pragmatic, open-label, two-arm feasibility randomised control trial (RCT) with an embedded interview component recruiting across three NHS sites comparing surgical treatment to a package of best conservative care; ‘Personalised Knee Therapy’ (PKT). The primary feasibility outcome was the recruitment rate per centre (expected rate 1 to 1.5 participants recruited each month). Secondary outcomes included the rate of follow-up (over 80% expected at 12 months) and a series of participant-reported outcomes taken at 3, 6 and 12 months following randomisation, including the Norwich Patellar Instability Score (NPIS), the Kujala Patellofemoral Disorder Score (KPDS), EuroQol-5D-5L, self-reported global assessment of change, satisfaction at each time point and resources use.

Results

We recruited 19 participants. Of these, 18 participants (95%) were followed-up at 12 months and 1 (5%) withdrew. One centre recruited at just over one case per month, one centre was unable to recruit, and one centre recruited at over one case per month after a change in participant screening approach. Ten participants were allocated into the PKT arm, with nine to the surgical arm. Mean Norwich Patellar Instability Score improved from 40.6 (standard deviation 22.1) to 28.2 (SD 25.4) from baseline to 12 months.

Conclusion

This feasibility trial identified a number of challenges and required a series of changes to ensure adequate recruitment and follow-up. These changes helped achieve a sufficient recruitment and follow-up rate. The revised trial design is feasible to be conducted as a definitive trial to answer this important clinical question for people with chronic patellar instability.

Trial registration

The trial was prospectively registered on the International Standard Randomised Controlled Trial Number registry on the 22/12/2016 (reference number: ISRCTN14950321). http://www.isrctn.com/ISRCTN14950321

Surgical versus conservative treatment for first patellofemoral dislocations: a meta-analysis of clinical trials

INTRODUCTION

The first approach for acute patellar dislocation is still a debated topic. The purpose of the present study was to perform a meta-analysis evaluating the outcomes of the surgical approach compared to the conservative treatments for primary acute patellar dislocation. We hypothesize that a prompt surgical treatment may lead to better outcomes in terms of re-dislocations and quality of life.

METHODS

This meta-analysis was performed according to the PRISMA guidelines. All the prospective clinical trials comparing surgical and conservative treatment for first acute patellofemoral dislocation were included in this study. For the methodological quality assessment, the PEDro appraisal score was adopted. For the risk of publication bias, the funnel plot was performed. The statistical analysis was performed using the Review Manager Software 5.3 (The Nordic Cochrane Collaboration, Copenhagen).

RESULTS

The funnel plot detected a low risk of publication bias. According to the PEDro score, the methodological quality assessment was good. Data from 654 patients were collected, undergoing a mean of 53.8 ± 48.4 month follow-up. A total of 311 patients (17.66 ± 4.1 years old) were analyzed in the surgery group and 291 patients (19.25 ± 4.5 years old) in the conservative ones. The mean Kujala score resulted in greater favor of the surgery group (MD: 9.99%; P = 0.006). The analysis of the comparison of re-dislocations resulted in favor of the surgery group (OR: 0.41; P < 0.0001). The analysis of the comparison of persistent joint instability resulted in favor of the surgery group (OR: 0.41; P < 0.0001).

CONCLUSIONS

Data from the present study encourage a prompt surgical approach for the first patellofemoral dislocation.

Surgical treatment is better than non-surgical treatment for primary patellar dislocation: a meta-analysis of randomized controlled trials

BACKGROUND

At present, the best treatment for primary patellar dislocation (PPD) has not been unified. Moreover, meta-analyses comparing the non-surgical and surgical treatments of PPD are lacking. Thus, we aimed to compare the clinical efficacy of surgical or non-surgical treatment of PPD.

METHODS

Randomized controlled studies of surgical and non-surgical treatments of PPD from 1966 to 2018 were retrieved from the following databases: PubMed, EMBASE, Cochrane Library, Wanfang Database, China Knowledge Network, Google Scholar, and Weipu Database. We screened for literature that met the inclusion criteria and extracted useful data for our meta-analysis.

RESULTS

Nine studies, involving 492 patients, met the inclusion criteria and were analyzed in this study. The recurrence rate of patellar dislocation in the surgical group was lower than that in the non-surgical group (P = 0.04]). Subgroup analysis according to the follow-up time showed that the Kujala score (P < 0.001) and lower recurrence rate of dislocation (P = 0.05) than the non-surgical group in the short term. Subgroup analysis according to surgical year showed that the surgical group get higher Kujala score (P < 0.001) and lower recurrence rate of dislocation (P = 0.01) than the non-surgical group in recent years.

CONCLUSION

Surgical treatment can provide better clinical results in a short period of time, and patients may achieve good results within 10 years owing to the advances in surgical techniques and instruments. Thus, we recommend surgical treatment as the preferred treatment for primary patellar dislocation.

A Meta-analysis of Surgical Versus Nonsurgical Treatment of Primary Patella Dislocation

PURPOSE

To compare outcomes after surgery versus nonsurgical treatment in the management of primary lateral patellar dislocation (LPD) through a meta-analysis of randomized controlled trials (RCTs) in terms of redislocation rate and clinical outcome, investigating both short-term (<6 years) functional recovery and overall benefit over time (>6 years).

METHODS

A systematic search of the literature was performed in November 2018. Risk of bias and quality of evidence were evaluated according to the Cochrane guidelines. RCTs investigating differences between surgery and nonsurgical treatment in primary LPD were included. The outcomes evaluated were redislocation rate, reinterventions, and Kujala score at short-, mid-, and long-term follow-up, with subanalyses for the pediatric population.

RESULTS

We included 510 patients from 10 RCTs in the meta-analysis. Redislocation rate was 0.40 (0.25 to 0.66; P < .001) and 0.58 (0.29 to 1.15; P = .12) at the short- and mid-term follow-ups, respectively, and the risk ratio for the need for further operations at 6 to 9 months' follow-up was 0.14 (0.02 to 1.03; P = .05), all favoring surgery. Concerning the Kujala score, an advantage of the surgical approach of 10.2 points (1.6 to 18.7; P = .02) at short-term follow-up was seen, whereas long-term follow-up results were similar between the groups. The subanalysis of the pediatric population at heterogeneous follow-up confirmed a lower risk of recurrence in surgery, with a risk ratio of 0.60 (0.26 to 1.37; P = .22), although not significant.

CONCLUSION

The literature documents a low number of high-level trials. The meta-analysis of RCTs underlined that the redislocation rate is higher with the nonsurgical approach compared with the surgical one. Moreover, when looking at the clinical outcome, more favorable findings were found with the surgical approach up to 6 years, whereas results seems to be similar at a longer follow-up after either surgical or nonsurgical treatment of primary LPD.

LEVEL OF EVIDENCE

II, meta-analysis of level I and level II randomized clinical trials.

Surgical versus nonsurgical treatment of primary acute patellar dislocation: A systematic review and meta-analysis

BACKGROUND

To systematically review the efficacy of surgical versus nonsurgical treatment for acute patellar dislocation.

MATERIALS AND METHODS

PubMed, Cochrane, and Embase were searched up to February 12, 2019. After removing duplicates, preliminary screening, and reading the full texts, we finally selected 16 articles, including 11 randomized controlled trials and 5 cohort studies. The quality of the enrolled studies was evaluated by Jadad score or Newcastle-Ottawa scale. Meta-analyses were performed using odds ratio (OR) and standardized mean difference (SMD) as effect variables. The clinical parameters assessed included mean Kujala score, rate of redislocation, incidence of patellar subluxation, patient satisfaction, and visual analog scale (VAS) for pain. Evidence levels were determined using GRADE profile.

RESULTS

The 16 included studies involved 918 cases, 418 in the surgical group and 500 in the nonsurgical group. The results of the meta-analysis showed higher mean Kujala score (SMD = 0.79, 95% confidence interval [CI] [0.3, 1.28], P = .002) and lower rate of redislocation (OR = 0.44, 95% CI [0.3, 0.63], P < .00001) in the surgical group than the nonsurgical group, but showed insignificant differences in the incidence of patellar subluxation (OR = 0.61, 95% CI [0.36, 1.03], P = .06), satisfaction of patients (OR = 1.44, 95% CI [0.64, 3.25], P = .38), and VAS (SMD = 0.84, 95% CI [-0.36, 9.03], P = .84).

CONCLUSION

For patients with primary acute patellar dislocation, surgical treatment produces a higher mean Kujala score and a lower rate of redislocation than nonsurgical treatment.

Patellar maltracking: an update on the diagnosis and treatment strategies

Patellar maltracking occurs as a result of an imbalance in the dynamic relationship between the patella and trochlea. This is often secondary to an underlying structural abnormality. The clinical evaluation can provide useful clues for the presence of such entity; however, the diagnosis can often be challenging especially in the absence of a documented history of patellar dislocation. Imaging, particularly MRI, can detect subtle features that could lead to the diagnosis, probably even more importantly when there is no clear history of patellar dislocation or before its development. This can provide a road map for formulating a treatment strategy that would be primarily aimed at stabilizing the patellofemoral joint to halt or slow the progression of articular cartilage loss. The purpose of this article is to discuss the clinical and radiologic evaluation of patellar maltracking providing an update on the cross-sectional imaging assessment and also a synopsis of the management options.

Recurrence of Patellar Instability in Adolescents Undergoing Surgery for Osteochondral Defects Without Concomitant Ligament Reconstruction

BACKGROUND

First-time patellar dislocation with an associated chondral or osteochondral loose body is typically treated operatively to address the loose fragment. The incidence of recurrent instability in this patient population if the medial patellofemoral ligament (MPFL) is not reconstructed is unknown.

PURPOSE

To determine the recurrent instability rate in patients undergoing surgery for patellar instability with chondral or osteochondral loose bodies, as well as to identify and stratify risk factors for recurrent instability.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This was a retrospective analysis of adolescent patients treated operatively for acute patellar dislocation with associated chondral or osteochondral loose bodies between 2010 and 2016 at a single pediatric level I trauma center with minimum 2-year follow-up. Potential demographic, injury-related, radiographic, and surgical risk factors were recorded. The primary outcome variable was recurrent subluxation and/or dislocation. Secondary outcome variables included need for additional procedures, Kujala score, Single Assessment Numerical Evaluation (SANE) score, and patient satisfaction.

RESULTS

Forty-one patients were included. In total, 61% experienced recurrent instability at a mean follow-up of 4.1 years and 39% required subsequent MPFL reconstruction. Tibial tubercle-trochlear groove (TT-TG) distance greater than 15 mm was a risk factor for recurrent instability ( P = .03). Patients with TT-TG distance greater than 15 mm and greater than 20 mm had recurrent instability rates of 75% and 86%, respectively. MPFL repair did not reduce the rate of recurrent instability ( P = .87). Recurrent instability was associated with significantly worse mean Kujala (93.9 vs 83.0; P = .01), SANE (88.9 vs 73.1; P = .01), and patient satisfaction scores (9.4 vs 7.3; P = .002).

CONCLUSION

If the MPFL is not reconstructed during index loose body treatment, children have a 61% recurrent instability rate. Patients with TT-TG distance greater than 15 mm, and particularly greater than 20 mm, are at highest risk for recurrent instability.

Arthroscopic reduction of a locked patellar dislocation: a new less invasive technique

Patellar dislocation is a condition that is often reduced by itself or through closed manipulation from a trained professional. In this case of a traumatic lateral patellar dislocation, the patella was caught through the rupture in the lateral retinaculum, as is seen in Boutonniere-like lesions. Reduction of the dislocated patella was obtained by arthroscopic reduction.Level of evidence V.

Clinical Outcomes After the Nonoperative Management of Lateral Patellar Dislocations: A Systematic Review

Background:

The first-line treatment for patellar dislocations is often nonoperative and consists of physical therapy and immobilization techniques, with various adjuncts employed. However, the outcomes of nonoperative therapy are poorly described, and there is a lack of quality evidence to define the optimal intervention.

Purpose:

To perform a comprehensive review of the literature and assess the quality of studies presenting patient outcomes from nonoperative interventions for patellar dislocations.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

The MEDLINE, AMED, Embase, CINAHL, Cochrane Library, PEDro, and SPORTDiscus electronic databases were searched through July 2017 by 3 independent reviewers. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Study quality was assessed using the CONSORT (Consolidated Standards for Reporting Trials) criteria for randomized controlled trials and the Newcastle-Ottawa Scale for cohort studies and case series.

Results:

A total of 25 studies met our inclusion criteria, including 12 randomized controlled trials, 7 cohort studies, and 6 case series, consisting of 1066 patients. Studies were grouped according to 4 broad categories of nonoperative interventions based on immobilization, weightbearing status, quadriceps exercise type, and alternative therapies. The most commonly used outcome measure was the Kujala score, and the pooled redislocation rate was 31%.

Conclusion:

This systematic review found that patient-reported outcomes consistently improved after all methods of treatment but did not return to normal. Redislocation rates were high and close to the redislocation rates reported in natural history studies. There is a lack of quality evidence to advocate the use of any particular nonoperative technique for the treatment of patellar dislocations.

Predicting Risk of Recurrent Patellar Dislocation

PURPOSE OF REVIEW

Lateral patellar dislocation (LPD) is one of the most common injuries of the knee, especially in a young patient. It is multifactorial with several underlying risk factors. The purpose of this review is to present the most recent data concerning risk factors and their predictive value to estimate recurrent LPD risk.

RECENT FINDINGS

Several demographic risk factors (age, skeletal immaturity, sex, bilaterality), mechanism of injury, and anatomic risk factors (trochlear dysplasia, patella alta, excessive tibial tubercle lateralization, increased patellar tilt) have been recognized. The combination of different risk factors, their relative contribution to instability, weightage of each factor, and multivariate analysis have led to the development of a prediction model and instability scoring system. If recurrent instability and poor outcomes could be predicted based on these prediction tools, then alternative treatment or early surgical intervention after first-time LPD could be considered. This information can also be used to predict contralateral LPD and failure of surgical treatment. Current prediction tools are mainly based on retrospective studies. In the future, prospective validation of these prognostic factors would be beneficial.

Does different duration of non-operative immobilization have an effect on the redislocation rate of primary patellar dislocation? A retrospective multicenter cohort study

BACKGROUND

Immobilization devices such as plaster splints, casts and braces have been used for first time patellar dislocation (FTPD) in order to prevent redislocation. This study evaluates different non-operative immobilization regimes upon rates of redislocation.

METHODS

A retrospective cohort study with a study population of 1366 in which 601 subjects under 30years with FTPD were included from three hospitals. Exclusion criteria were osteochondral fracture, ligament injury and subluxation. Subjects were divided into five groups; unknown/none, two weeks of brace, two weeks of brace followed by bandage, four weeks of brace and six weeks of brace with increasing of range of motion. Radiographs were evaluated for trochlear dysplasia (TD), patella alta, trochlear depth and growth zone. Crude analysis and logistic regression adjusted for radiographic assessments, age, gender and rehabilitation was done in STATA® with significance p≤0.05.

RESULTS

Forty-five point eight percent were between 15 and 19years and 51.4% were male. One hundred sixty-three experienced redislocation (27.1%). Logistic regression was performed at 404 subjects and showed that rehabilitation, gender, TD, patella alta, and growth zone had no significant odds ratio (OR) on redislocation. The duration of brace demonstrated no significant OR in reducing redislocation. Subjects between 20 and 29years showed lower OR in redislocation (95% CI) of 0.27 (0.11; 0.64, p=0.003).

CONCLUSION

This study demonstrated no difference in duration of brace treatment in reducing patella redislocation after FTPD. Rehabilitation and predisposal factors such as TD, trochlear depth, patella alta and open growth zone did not influence the redislocation rate. Increasing age reduced risk of redislocation.

Paediatric First-Time Patella Dislocators: An Approach to Conservative Management

Background

First-time lateral patella dislocations are generally treated nonoperatively. However, the ideal form of conservative management and immobilization remains unknown. We compare the clinical outcomes after different immobilization methods.

Methods

Paediatric-age patients that met our inclusion criteria, and presenting with a first episode of lateral patella dislocation to our hospital from 2006 to 2013, were enrolled. Different immobilization methods included brace, backslab, or cylinder cast. A retrospective review was performed to compare bracing against other immobilization methods, using a primary outcome measure of redislocation rate, and secondary outcome measures like progression to surgery, range-of-motion, pain, and weight-bearing status.

Results

A total of 142 patients (with 147 affected knees) with minimum 1 -year follow-up were included in the study. Bracing was found to be superior to other immobilization methods in preventing repeat dislocations, and need for subsequent surgery. At 6 weeks, patients treated with the backslab had the highest incidence of pain. There were no differences with regards to range-of-motion or weight-bearing status.

Conclusion

We recommend the use of a brace, with a progressive rehabilitation protocol in the management of first-time lateral patella dislocators. This study is also unique, in that it specifically addresses nonoperative management of first time patella dislocators in a paediatric-age population group.

Treatment of Primary Acute Patellar Dislocation: Systematic Review and Quantitative Synthesis of the Literature

PURPOSE

The aim of this study was to evaluate clinical outcomes, rate of redislocation, and complications after conservative or surgical procedures used to treat primary acute patellar dislocation.

METHODS

A comprehensive search of PubMed, Medline, CINAHL, Cochrane, Embase, and Google Scholar databases using various combinations of the keywords "patella," "dislocation," "treatment," "acute," "primary" was performed. The following data were extracted: demographics, chondral defects and soft tissue lesions, outcome measurements, type of management, recurrence of instability, and complications.

RESULTS

A total of 2134 knees in 2086 patients were included, with an average age at dislocation of 20.3 years. The average Kujula score was 75.6 for patients treated conservatively and 88.7 for patients undergoing surgical treatment in the short-medium follow-up (less than 5 years); the average Kujula score was 87.5 for patients treated conservatively and 86.6 for patients undergoing surgical treatment in the long-term follow-up (more than 5 years). The rate of recurrence was significantly lower in the surgical group (25%) than in the conservative group (36.4%). The overall complication rate was 6.5% (29 of 441 knees) in the surgical management group. No complications were reported for patients treated conservatively.

CONCLUSIONS

Surgical treatment of primary acute patellar dislocation leads to significantly lower rate of redislocation and provides better short-medium clinical outcomes, whereas in the long-term follow-up, results of patients treated conservatively were as good as those of surgical patients. Further randomized controlled trials, describing anatomical abnormalities and soft-tissue integrity that may influence the choice of treatment, are needed.

LEVEL OF EVIDENCE

Systematic review, level IV.

Patella dislocations

The patellofemoral joint relies on muscular, ligamentous and bony support for normal stability and function. Dislocations commonly occur due to simultaneous rotational force with contraction of the quadriceps. Bony, muscular and ligamentous factors predispose to dislocations although no single factor causes more dislocations than any other. The diagnosis is based on the history combined with physical examination and radiological investigations. A careful scrutiny of the radiographs is necessary to determine the presence of osteochondral fractures in acute patellar dislocations. Special views and further imagining is indicated especially in those with recurrent symptoms. The treatment of acute dislocations is most commonly non operative. Surgery in acute patellar dislocations is indicated for intra articular fragments or those with large osteochondral fractures. Various soft tissue and bony realignment procedures have been described for recurrent dislocations. No single procedure is superior to another. Factors such as the patient’s age, functional needs, extent of malalignment and the condition of the joint are important factors to be considered prior to operative intervention. In this paper we discuss an overview of the diagnosis and management of patella dislocations with a literature review on the current concepts in treatment.

Surgical versus conservative management of acute patellar dislocation in children and adolescents: a systematic review

PURPOSE

The goal of this study was to perform a comparative review to determine whether there is a significant difference in the rate of repeat dislocation and clinical outcome between surgical and conservative management of acute patellar dislocation in children and adolescents.

METHODS

A systematic review of the MEDLINE database was performed. English-language clinical outcome studies with a primary outcome/treatment specific to acute patella dislocation in a paediatric population were included. Eleven studies met inclusion criteria; Chi-square analysis, independent t tests and weighted mean pooled cohort statistics were performed where appropriate.

RESULTS

A total of 470 conservatively managed and 157 operatively treated knees were included. Conservatively managed patients were on average 17.0 years and had a mean follow-up of 3.9 years; surgically managed patients were on average 16.1 years and had a mean follow-up of 4.7 years. Conservatively managed knees had a 31% rate of recurrent dislocation rate compared to 22% in surgical knees (p = 0.04). Trochlear dysplasia and skeletal immaturity confer greater risk for recurrent instability. Surgical treatment may provide clinically important quality of life and sporting benefit.

CONCLUSIONS

Surgical treatment of first time patella dislocation in children and adolescents is associated with a lower risk of recurrent dislocation and higher health-related quality of life and sporting function. There is a paucity of evidence on MPFL reconstruction for first time traumatic patella dislocation in this population.

LEVEL OF EVIDENCE

IV.

Is surgical treatment better than conservative treatment for primary patellar dislocations? A meta-analysis of randomized controlled trials

BACKGROUND

Despite several randomized controlled trials comparing operative to nonoperative management of primary patellar dislocation, the optimal management of this condition remains a subject of controversy. The aim of this study was to compare surgical to conservative treatment of outcomes for primary patellar dislocation by meta-analysis all the relative randomized controlled trials.

STUDY DESIGN

Meta-analysis.

METHODS

After searching multiple online databases (MEDILINE, EMBASE, CLINICAL, OVID, BISOS and Cochrane registry of controlled clinical trials), eight randomized controlled trials including 430 patients were meta-analyzed in which operative treatment was compared with non-operative treatment for primary patellar dislocation. Outcomes evaluated were redislocation rate, Kujala score, episode of instability, Tegner activity score, Hughston visual analog score (VAS) and patient satisfaction.

RESULTS

Outcomes on recurrent patellar dislocation (P = 0.004) and Hughston VAS (P = 0.03) were statistically significant in favor of operative management. Tegner activity score (P < 0.00001) was significantly higher in favor of conservative treatment, though only a few studies were identified. There was no significant difference between the two treatments regarding episode of instability (P = 0.41), Kujala score (P = 0.32) or patient satisfaction (P = 0.49).

CONCLUSION

Surgical treatment may be better than conservative treatment for patients with primary patellar dislocation on incidence of redislocation. However, since these findings are built on a limited number of studies available, well-designed, multicenter clinical trials with long-term follow-up are required to provide more solid evidence concerning optimal strategies.

Management of Acute Patellar Dislocation: A Case Report

OBJECTIVE

The purpose of this case study is to describe the evaluation and management of patellar dislocations and the different approaches used from providers in different countries.

CLINICAL FEATURES

An individual dislocated her left patella while traveling abroad and received subsequent care in Thailand, China, and the United States.

INTERVENTION AND OUTCOME

Nonoperative treatment protocols including manual closed reduction of the patella, casting of the leg, and rehabilitation exercises were employed.

CONCLUSION

Receipt of care when abroad can be challenging. The patient's knee range of motion and pain continued to improve when she was diligent about performing the home exercise program. This case highlights the importance of a thorough examination, a proper regimen of care, and patient counseling to ensure a full recovery and minimize the chance of re-injury.

Classification of Lateral Patellar Instability in Children and Adolescents

There is significant heterogeneity in the literature related to the causes and treatment of patellar instability. To address the multifactorial issue of patellar instability, the first task is to classify the instability pattern. Once a classification system is developed, future studies can differentiate between treatment recommendations and outcomes for each instability pattern. Existing classification systems do not include the entire spectrum of patellar instability patterns. The aim of this article is to review the nomenclature and existing patellar instability classification systems and analyze the different patterns into a comprehensive system.

RANDOMIZED PROSPECTIVE STUDY ON TRAUMATIC PATELLAR DISLOCATION: CONSERVATIVE TREATMENT VERSUS RECONSTRUCTION OF THE MEDIAL PATELLOFEMORAL LIGAMENT USING THE PATELLAR TENDON, WITH A MINIMUM OF TWO YEARS OF FOLLOW-UP

Objective: The aim of this study was to compare the surgical results from reconstruction of the medial patellofemoral ligament (MPFL) with non-operative treatment of primary patellar dislocation. Methods: Thirty-nine patients (41 knees) with patellar dislocation were randomized into two groups. One group was treated conservatively (immobilization and physiotherapy) and other was treated surgically with reconstruction of the MPFL, and the results were evaluated with a minimum follow-up of two years. The Kujala questionnaire was applied to assess pain and quality of life, and recurrences were evaluated. Pearson's chi-square test and Fisher's exact test were used in the statistical evaluation. Results: The statistical analysis showed that the mean Kujala score was significantly lower in the conservative group (70.8), compared with the mean value in the surgical group (88.9), with p = 0.001. The surgical group presented a higher percentage of “good/excellent” Kujala score results (71.43%) than in the conservative group (25.0%), with p = 0.003. The conservative group presented a greater number of recurrences (35% of the cases), while in the surgical group there were no reports of recurrences and/or subluxation. Conclusions: Treatment with reconstruction of the medial patellofemoral ligament using the patellar tendon produced better results, based on the analysis of post-treatment recurrences and the better final results from the Kujala questionnaire after a minimum follow-up period of two years.

Current Concepts for Patellar Dislocation

Context:

Patellar dislocation usually occurs to the lateral side, leading to ruptures of the Medial Patellofemoral Ligament (MPFL) in about 90% of the cases. Even though several prognostic factors are identified for patellofemoral instability after patellar dislocation so far, the appropriate therapy remains a controversial issue.

Evidence Acquisition:

Authors searched the Medline library for studies on both surgical and conservative treatment for patellar dislocation and patellofemoral instability. Additionally, the reference list of each article was searched for additional studies.

Results:

A thorough analysis of the anatomical risk factors with a particular focus on patella alta, increased Tibial Tuberosity-Trochlear Groove (TT-TG) distance, trochlear dysplasia as well as torsional abnormalities should be performed early after the first dislocation to allow adequate patient counseling. Summarizing the results of all published randomized clinical trials and comparing surgical and conservative treatment after the first-time patellar dislocation until today indicated no significant evident difference for children, adolescents, and adults. Therefore, nonoperative treatment was indicated after a first-time patellar dislocation in the vast majority of patients.

Conclusions:

Surgical treatment for patellar dislocation is indicated primarily in case of relevant concomitant injuries such as osteochondral fractures, and secondarily for recurrent dislocations.

Surgical versus conservative treatment of primary patellar dislocation. A systematic review and meta-analysis

PURPOSE

The purpose of this study was to determine the efficacy of surgical and conservative treatment in the prevention of recurrence after primary patellar dislocation.

METHODS

Studies were searched on MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and CINHAL from their inception to April 2015. All randomized controlled clinical trials comparing surgical versus conservative treatment after first patellar dislocation were included. Primary outcomes were: recurrent dislocation, subluxation, overall instability and subsequent surgery. Secondary outcomes included imaging, and subjective and objective clinical assessment tools. Methodological quality of the studies was assessed using Cochrane Collaboration's "Risk of Bias" tool. Pooled analyses were reported as risk ratio (RR) using a random effects model. Continuous data were reported as standardized mean difference (SMD) and 95 % confidence intervals (CIs). Heterogeneity was assessed using I².

RESULTS

Nine studies were included in the meta-analyses. Methodological quality of the studies was moderate to low. Meta-analyses showed that surgical treatment significantly reduces the redislocation rate (RR = 0.62; 95% CI = 0.39, 0.98, p = 0.04) and provides better results on Hughston VAS score (SMD = -0.32; 95% CI = -0.61, -0.03; p = 0.03) and running (OR = -0.52; 95% CI = 0.31, 0.88; p = 0.01). Conservative treatment showed less occurrence of minor complications (OR = 3.46; 95% CI = 2.08, 5.77; p = 0.01) and better results in the figure-of-8 run test (SMD = 0.42; 95% CI = 0.06, 0.77; p = 0.02) and in the squat down test (SMD = -0.45; 95% CI = -0.81, -0.10; p < 0.00001). No other significant differences could be found.

CONCLUSIONS

Based on the available data, surgical treatment of primary patella dislocation significantly reduces the risk of patella redislocation.

Medial patellofemoral ligament tears in the setting of multiligament knee injuries rarely cause patellar instability

BACKGROUND

Multiligament knee injuries (MLKIs) can also involve the medial patellofemoral ligament (MPFL), but there is a paucity of information regarding prevalence and relevance of MPFL involvement in this setting.

PURPOSE

(1) To identify the prevalence of MPFL injury in MLKIs, (2) to determine whether an MPFL tear results in symptomatic patellar instability, and (3) to report clinical and functional outcomes of patients with and without MPFL tears after MLKI surgical reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The records of all patients who underwent surgical reconstruction of MLKI (defined as a grade 3 injury of ≥2 ligaments) at a single institution from 2007 to 2010 were reviewed. Age, sex, knee dislocation classification (according to Schenck), and MRI findings were documented. All preoperative MRI scans were reviewed by an experienced musculoskeletal radiologist to determine the presence or absence of MPFL involvement. If an MPFL tear was present, its anatomic location and severity as well as the presence of patellar or lateral femoral condyle bone bruises were documented. Inclusion criteria included (1) MLKI treated at a single institution, (2) presence of MPFL tear on preoperative MRI, and (3) minimum 2-year clinical follow-up. Patellar instability symptoms were assessed with the Kujala Knee Questionnaire. Functional outcomes were measured using the International Knee Documentation Committee (IKDC) score. IKDC scores were compared between patients who sustained MLKIs with and without MPFL tears. There were 21 patients in each group.

RESULTS

Over the 4-year study period, 30 of 51 patients (59%) treated surgically for a MLKI had MRI evidence of an MPFL tear. Nine were lost to follow-up, leaving 21 patients for review. There were 13 complete (62%), 5 high-grade partial (24%), and 3 partial (14%) MPFL tears. Sixteen of 21 tears (76%) occurred at the proximal third, with the remainder exhibiting diffuse signal abnormality consistent with tearing throughout the length of the MPFL. The superficial medial collateral ligament was involved in all patients. In no case was the MPFL repaired or reconstructed. At mean follow-up of 3.6 years (range, 2.0-5.7 years), only 1 of 21 patients (5%) complained of patellofemoral instability symptoms whereas 20 of 21 patients (95%) did not experience patellar subluxation or dislocation. No significant difference was found when IKDC scores were compared between patients with and without an MPFL tear (mean ± SD, 65.5 ± 22.9 vs 79.4 ± 16.1; P = .07).

CONCLUSION

MPFL tears occur frequently in patients with MLKI but rarely cause instability. In the majority of cases, MPFL tears do not need to be addressed at the time of surgery.

Does Operative Treatment of First-Time Patellar Dislocations Lead to Increased Patellofemoral Stability? A Systematic Review of Overlapping Meta-analyses

PURPOSE

To conduct a systematic review of meta-analyses comparing nonoperative and operative treatment of patellar dislocations to elucidate the cause of the variation and to determine which meta-analysis provides the current best available evidence.

METHODS

A systematic review of the literature to identify meta-analyses was performed. Data were extracted for patient outcomes and recurrent dislocations. Meta-analysis quality was assessed using the Oxman-Guyatt and Quality of Reporting of Meta-analyses systems. The Jadad algorithm was then applied to determine which meta-analysis provided the highest level of evidence.

RESULTS

Four meta-analyses met the eligibility criteria: 1 Level I evidence, 2 Level II evidence, and 1 Level III evidence. A total of 1,984 patients were included (997 underwent surgery whereas 987 underwent conservative treatment). Three meta-analyses found a lower subsequent patellar dislocation rate in patients managed operatively compared with nonoperatively, whereas one did not find a difference in recurrent dislocation rates between the operative and nonoperative groups. When the results of all the studies were combined, the overall redislocation rate was 29.4% and the rate of recurrent instability episodes was 32.8%. Patients treated operatively had a 24.0% rate of repeat patellar dislocation and a 32.7% rate of recurrent patellar instability, whereas patients treated nonoperatively had a 34.6% rate of repeat patellar dislocation and a 33.0% rate of recurrent instability. In addition, 1 meta-analysis found a significantly higher rate of patellofemoral osteoarthritis in the operative group. No differences in functional outcomes scores were seen between treatments. Two meta-analyses had low Oxman-Guyatt scores (<4), indicative of major flaws.

CONCLUSIONS

According to the best available evidence, operative treatment of acute patellar dislocations may result in a lower rate of recurrent dislocations than nonoperative treatment but does not improve functional outcome scores.

LEVEL OF EVIDENCE

Level III, systematic review of Level I, II, and II studies.

Evaluation and management of patellar instability in pediatric and adolescent athletes

CONTEXT

The rising popularity and intensity of youth sports has increased the incidence of patellar dislocation. These sports-related injuries may be associated with significant morbidity in the pediatric population. Treatment requires understanding and attention to the unique challenges in the skeletally immature patient.

EVIDENCE ACQUISITION

PubMed searches spanning 1970-2013.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 5.

RESULTS

Although nonoperative approaches are most often suitable for first-time patellar dislocations, surgical treatment is recommended for acute fixation of displaced osteochondral fractures sustained during primary instability and for patellar realignment in the setting of recurrent instability. While a variety of procedures can prevent recurrence, the risk of complications is not minimal.

CONCLUSION

Patellar stabilization and realignment procedures in skeletally immature patients with recurrent patellar dislocation can effectively treat patellar instability without untoward effects on growth if careful surgical planning incorporates protection of growth parameters in the skeletally immature athlete.

Surgical versus non-surgical interventions for treating patellar dislocation

BACKGROUND

Patellar dislocation occurs when the patella disengages completely from the trochlear (femoral) groove. Following reduction of the dislocation, conservative (non-surgical) rehabilitation with physiotherapy may be used. Since recurrence of dislocation is common, some surgeons have advocated surgical intervention rather than non-surgical interventions. This is an update of a Cochrane review first published in 2011.

OBJECTIVES

To assess the effects (benefits and harms) of surgical versus non-surgical interventions for treating people with primary or recurrent patellar dislocation.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group's Specialised Register, the Cochrane Central Register of Controlled Trials (The Cochrane Library), MEDLINE, EMBASE, AMED, CINAHL, ZETOC, Physiotherapy Evidence Database (PEDro) and a variety of other literature databases and trial registries. Corresponding authors were contacted to identify additional studies. The last search was carried out in October 2014.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled clinical trials evaluating surgical versus non-surgical interventions for treating lateral patellar dislocation.

DATA COLLECTION AND ANALYSIS

Two review authors independently examined titles and abstracts of each identified study to assess study eligibility, extract data and assess risk of bias. The primary outcomes we assessed were the frequency of recurrent dislocation, and validated patient-rated knee or physical function scores. We calculated risk ratios (RR) for dichotomous outcomes and mean differences MD) for continuous outcomes. When appropriate, we pooled data.

MAIN RESULTS

We included five randomised studies and one quasi-randomised study. These recruited a total of 344 people with primary (first-time) patellar dislocation. The mean ages in the individual studies ranged from 19.3 to 25.7 years, with four studies including children, mainly adolescents, as well as adults. Follow-up for the full study populations ranged from two to nine years across the six studies. The quality of the evidence is very low as assessed by GRADE (Grading of Recommendations Assessment, Development and Evaluation Working Group) criteria, with all studies being at high risk of performance and detection biases, relating to the lack of blinding.There was very low quality but consistent evidence that participants managed surgically had a significantly lower risk of recurrent dislocation following primary patellar dislocation at two to five years follow-up (21/162 versus 32/136; RR 0.53 favouring surgery, 95% confidence interval (CI) 0.33 to 0.87; five studies, 294 participants). Based on an illustrative risk of recurrent dislocation in 222 people per 1000 in the non-surgical group, these data equate to 104 fewer (95% CI 149 fewer to 28 fewer) people per 1000 having recurrent dislocation after surgery. Similarly, there is evidence of a lower risk of recurrent dislocation after surgery at six to nine years (RR 0.67 favouring surgery, 95% CI 0.42 to 1.08; two studies, 165 participants), but a small increase cannot be ruled out. Based on an illustrative risk of recurrent dislocation in 336 people per 1000 in the non-surgical group, these data equate to 110 fewer (95% CI 195 fewer to 27 more) people per 1000 having recurrent dislocation after surgery.The very low quality evidence available from single trials only for four validated patient-rated knee and physical function scores (the Tegner activity scale, KOOS, Lysholm and Hughston VAS (visual analogue scale) score) did not show significant differences between the two treatment groups.The results for the Kujala patellofemoral disorders score (0 to 100: best outcome) differed in direction of effect at two to five years follow-up, which favoured the surgery group (MD 13.93 points higher, 95% CI 5.33 points higher to 22.53 points higher; four studies, 171 participants) and the six to nine years follow-up, which favoured the non-surgical treatment group (MD 3.25 points lower, 95% CI 10.61 points lower to 4.11 points higher; two studies, 167 participants). However, only the two to five years follow-up included the clear possibility of a clinically important effect (putative minimal clinically important difference for this outcome is 10 points).Adverse effects of treatment were reported in one trial only; all four major complications were attributed to the surgical treatment group. Slightly more people in the surgery group had subsequent surgery six to nine years after their primary dislocation (20/87 versus 16/78; RR 1.06, 95% CI 0.59 to 1.89, two studies, 165 participants). Based on an illustrative risk of subsequent surgery in 186 people per 1000 in the non-surgical group, these data equate to 11 more (95% CI 76 fewer to 171 more) people per 1000 having subsequent surgery after primary surgery.

AUTHORS' CONCLUSIONS

Although there is some evidence to support surgical over non-surgical management of primary patellar dislocation in the short term, the quality of this evidence is very low because of the high risk of bias and the imprecision in the effect estimates. We are therefore very uncertain about the estimate of effect. No trials examined people with recurrent patellar dislocation. Adequately powered, multi-centre, randomised controlled trials, conducted and reported to contemporary standards, are needed. To inform the design and conduct of these trials, expert consensus should be achieved on the minimal description of both surgical and non-surgical interventions, and the anatomical or pathological variations that may be relevant to both choice of these interventions and the natural history of patellar instability. Furthermore, well-designed studies recording adverse events and long-term outcomes are needed.

Acute traumatic patellar dislocation

Inaugural traumatic patellar dislocation is most often due to trauma sustained during physical or sports activity. Two-thirds of acute patellar dislocations occur in young active patients (less than 20 years old). Non-contact knee sprain in flexion and valgus is the leading mechanism in patellar dislocation, accounting for as many as 93% of all cases. The strong displacement of the patella tears the medial stabilizing structures, and notably the medial patellofemoral ligament (MPFL), which is almost always injured in acute patellar dislocation, most frequently at its femoral attachment. Lateral patellar glide can be assessed with the knee in extension or 20° flexion. Displacement by more than 50% of the patellar width is considered abnormal and may induce apprehension. Plain X-ray and CT are mandatory to diagnose bony risk factors for patellar dislocation, such as trochlear dysplasia or increased tibial tubercle-trochlear groove distance (TT-TG), and plan correction. MRI gives information on cartilage and capsulo-ligamentous status for treatment planning: free bodies or osteochondral fracture have to be treated surgically. If patellar dislocation occurs in an anatomically normal knee and osteochondral fracture is ruled out on MRI, non-operative treatment is usually recommended.

Troubleshooting the Femoral Attachment During Medial Patellofemoral Ligament Reconstruction: Location, Location, Location

The medial patellofemoral ligament (MPFL) has been recognized as an important soft tissue restraint in preventing lateral patellar translation. As many patients with acute or chronic patellar instability will have a deficient MPFL, reconstruction of this ligament is becoming more common. Appropriately, significant research has been undertaken regarding graft biomechanics and techniques, as intraoperative errors in graft placement often result in poor patient outcomes. Although the research has not answered all of the dilemmas encountered during reconstruction, publications consistently emphasize the importance of re-establishing an anatomic femoral attachment. The purpose of this study was to briefly review the current literature on MPFL reconstruction. Graft selection and patellar graft attachment and fixation are discussed, but the main focus is the femoral attachment as this is where most errors are seen and, unfortunately, where getting it right appears to matter the most. Using a sawbones knee model, the concepts of an MPFL graft that is “high and tight” or “low and loose” are presented, with the goal of providing physicians with intraoperative tools to adjust an incorrectly placed femoral MPFL attachment. This model is also used to justify the recommendation of graft fixation in 30° to 45° of knee flexion.

MPFL reconstruction: technique and results

Patellar instability is a common problem, and medial patellofemoral ligament (MPFL) injury is inherent with traumatic patellar dislocations. Initial nonoperative management is focused on reconditioning and strengthening the dynamic stabilizers of the patella. For those patients who progress to recurrent instability, further investigation into the predisposing factors is required. MPFL reconstruction is indicated in patients with recurrent instability and insufficient medial restraint due to MPFL injury. A technique of MPFL reconstruction is outlined. This procedure may also be performed in combination with other realignment procedures.

Long-term follow-up of nonoperatively and operatively treated acute primary patellar dislocation in skeletally immature patients

Purpose. The present study reports a long-term follow-up of acute primary patellar dislocation in patients with open physes. The purpose of the study was to evaluate knee function and recurrence rates after surgical and nonsurgical treatment of patellar dislocation. Methods. A total of 51 patients, including 29 girls and 22 boys, who were 9–14 years of age at the time of injury, were retrospectively evaluated. The minimum follow-up time was 5 years. Thigh muscle torque, range of motion, the squat test, the knee injury and osteoarthritis outcome score (KOOS), the Kujala score, and the recurrence rate were registered. Radiological predisposing factors at the time of injury were determined. Results. Quality of life and sports/recreation were the most affected subscales, according to KOOS, and a reduced Kujala score was also observed in all treatment groups. The surgically treated patients had a significantly lower recurrence rate. Those patients also exhibited reduced muscle performance, with a hamstring to quadriceps ratio (H/Q) of 1.03. The recurrence rate was not correlated with knee function. Conclusions. Patellar dislocation in children influences subjective knee function in the long term. Surgery appears to reduce the recurrence rate, but subjective knee function was not restored.

Axial knee radiographs: consistency across clinic sites

PURPOSE

(1) Do radiographic protocols for knee axial images vary across different clinic locations? (2) Does variability between radiographic positioning protocols (knee flexion angle, beam positioning) yield different radiographic measurements that could influence clinical assumptions?

METHODS

Radiographic positioning, including beam angle and knee flexion, was measured using a photograph taken of a phantom leg and (human) model set-up. An axial radiograph of a phantom leg was taken at seven different outpatients musculoskeletal clinics to assess patella position (lateral tilt/translation). The phantom leg patella was placed in an abnormal position for the radiographic image across all sites.

RESULTS

Knee flexion<30° was less accurate in obtaining requested knee flexion than higher knee flexion angles (phantom limb error averaged 6°, range 4°-7° human model error averaged 15°, range 11°-25°). Of the five sites utilizing a 'Merchants' axial radiographs, the congruence angle varied from +12° to +29°, being normal at one site (+12°) and abnormal (>+16°) at three sites, and negative at one site (-15°).

CONCLUSIONS

Radiographic protocols for knee axial imaging are inconsistent in radiographic positioning and imaging. This variability can lead to disparity in radiographic image results used for clinical decision-making. Standardization of radiographic positioning would yield more consistent imaging of patella position in early flexion, increasing clinical utility and accuracy.

Which patellae are likely to redislocate?

PURPOSE

The purpose of this study was to identify the risk factors for recurrent lateral patellar dislocations and to incorporate those factors into a patellar instability severity score.

METHODS

Sixty-one patients [male/female 35/26; median age 19 years (range 9-51 years)] formed the study group for this investigation. Within the study group, 40 patients experienced a patellar redislocation within 24 months after the primary dislocation, whereas 21 patients, who were assessed after a median follow-up of 37 months (range 24-60 months), had not experienced a subsequent episode of lateral patellar instability. In all patients, age at the time of the primary dislocation, gender, the affected body side, body mass index, bilateral instability, physical activity according to Baecke's questionnaire, the grade of trochlear dysplasia, patellar height, tibial tuberosity-trochlear groove (TT-TG) distance, and patellar tilt were assessed. The odds ratio (OR) of each factor with regard to the patellar redislocation was calculated using contingency tables. Based on these data, a "patellar instability severity score" was calculated.

RESULTS

The patellar instability severity score has six factors: age, bilateral instability, the severity of trochlear dysplasia, patella alta, TT-TG distance, and patellar tilt; the total possible score is seven. Reapplying this score to the study population revealed a median score of 4 points (range 2-7) for those patients with an early episode of patellar redislocation and a median score of 3 points (range 1-6) for those without a redislocation (p=0.0004). The OR for recurrent dislocations was 4.88 (95% CI 1.57-15.17) for the patients who scored 4 or more points when compared with the patients who scored 3 or fewer points (p=0.0064).

CONCLUSION

Based on the individual patient data, the patellar instability severity score allows an initial risk assessment for experiencing a recurrent patellar dislocation and might help differentiate between responders and non-responders to conservative treatment after primary lateral patellar instability.

LEVEL OF EVIDENCE

Case-control study, Level III.

Comparison operative and conservative management for primary patellar dislocation: an up-to-date meta-analysis

PURPOSE

The aim of this review was to compare the clinical outcomes between operative and conservative management for primary patella dislocation (PPD).

METHODS

PubMed Medline, EMBASE, Google scholar, and the Cochrane Library were systematically searched for randomized controlled trials that compared operative technique versus conservative technique for PPD. The results of eligible studies were independently extracted and analyzed according to the following: patient's satisfaction, Kujala score, Tegner score, and redislocation rate. Random-effect and fixed-effect models were adopted to calculate the weight mean difference and the odds ratio for continuous and dichotomous variables with 95 % confidence interval.

RESULTS

Seven studies met the inclusion criteria, resulting in 402 (216 surgery and 186 conservation) patients available for the present study. A meta-analysis showed no significant differences between the two treatment groups in terms of patient's satisfaction and Kujala score. However, significant differences in Tegner score (P < 0.00001) and redislocation rate (P = 0.002) were observed in favor of surgical treatment. In the subgroup analysis, surgical intervention achieved higher (P = 0.002) Kujala score in short term (<5 years), while conservation gained advantage (P = 0.003) in long term (>5 years). There was no significant difference in dislocation rate in long term.

CONCLUSIONS

Surgical treatment might provide better clinical results in short term. More persuasive evidence is still needed to proof the effect of surgical management in long time.

Return to activity after medial patellofemoral ligament repair or reconstruction

PURPOSE

This study aimed to determine the ability of patients to return to activity after medial patellofemoral ligament (MPFL) reconstruction or repair for patellar instability.

METHODS

A systematic review was performed using multiple databases. Studies reporting outcomes with Tegner scores after repair or reconstruction of the MPFL were included. Surgical technique, Tegner scores, and episodes of recurrent patellar instability were recorded.

RESULTS

Ten articles with a total of 402 patients were included. The mean preoperative Tegner score was 4.7 (2.9 to 7.5). The mean postoperative Tegner score was 5.8 (4.0 to 7.7). Forty-nine patients (12.2%) had a recurrent episode of instability, 11 of whom required additional corrective procedures. There was a statistically significant larger failure rate among those who underwent MPFL repair (26.9%) than those who underwent reconstruction (6.6%) or medial retinacular repair/plication (16.5%).

CONCLUSIONS

Recurrent dislocation was higher in patients who underwent MPFL repair rather than reconstruction. However, repair and reconstruction had similar Tegner scores. Repair or reconstruction of the soft tissue structures contributing to patellofemoral instability is successful in returning patients to preinjury activity levels.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III, and IV studies.