Liberação retinacular lateral da patela: o que mudou nos últimos dez anos

Evaluation of Differences in Patellar Height After Patellar Stabilization Procedures Not Intended to Address Patella Alta: A Multicenter Study

Background

Recent studies have reported conflicting results as to whether isolated medial patellofemoral ligament reconstruction (MPFLr) leads to decreased patellar height.

Purpose

To investigate if patellar stabilization surgery not intended to address patella alta influences patellar height.

Study Design

Cohort study; Level of evidence, 3.

Methods

A multicenter retrospective chart review was conducted, and patients who underwent MPFLr, medializing tibial tuberosity osteotomy (TTO), and/or trochleoplasty between 2016 and 2020 were included. The Caton-Deschamps index (CDI) was calculated from radiographs obtained preoperatively, 2 weeks postoperatively, and 3 months postoperatively. The preoperative CDI value was compared with the 2-week postoperative and 3-month postoperative values according to stabilization procedure (isolated MPFLr, isolated TTO, MPFLr + TTO, MPFLr + trochleoplasty, and MPFLr + trochleoplasty + TTO) using the paired t test. Analyses of the 1-bundle versus 2-bundle MPFLr technique and the presence of lateral retinacular release or lateral retinacular lengthening were conducted on the isolated MPFLr and combined MPFLr + TTO cohorts.

Results

A total of 356 knees were included. Statistically significant pre- to postoperative decreases in CDI were seen in all stabilization procedures analyzed (P≤ .017 for all). Within the isolated MPFLr cohort, this significant decrease was seen at 2 weeks postoperatively with the 2-bundle technique (ΔCDI = -0.09; P < .001) but not with the 1-bundle technique (ΔCDI = -0.01; P = .621).

Conclusion

The different surgical techniques analyzed in the current study affected patellar height, even when a distalizing TTO was not performed. The decrease was dependent on surgical technique, with a 2-bundle MPFLr leading to a statistically significant decrease and a 1-bundle MPFLr effecting no change.

Systematic lateral retinacular release does not reduce anterior knee pain after total knee arthroplasty with patellar resurfacing

PURPOSE

The aim of this study was to assess the effect of systematic lateral retinacular release (LRR) on anterior knee pain (AKP), as well as its impact on the functional and radiological outcomes after total knee arthroplasty (TKA) with patellar resurfacing.

METHODS

A prospective randomized study was designed. It included patients scheduled for a TKA procedure with patellar resurfacing, who were recruited and randomized into either the LRR group or the non-release group. 198 patients were included in the final analysis. The pressure pain threshold (PPT) assessed by pressure algometry (PA), the visual analogue scale (VAS), Feller's patellar score, the Knee Society Score (KSS), patellar height, and patellar tilt were recorded both preoperatively and at the 1-year follow-up. The Mann-Whitney U test was performed to determine comparisons between both groups as well as to determine differences' intragroup.

RESULTS

Relative to the clinical variables and scores, no difference was detected between the two groups at the 1-year follow-up (p = n.s.). However, there was a slight difference in patellar tilt (0.1º vs. 1.4º, p = 0.044), with higher tilt values in the non-release group. There was no difference in terms of improvement in the clinical and radiological scores and variables recorded between the two groups (p = n.s.).

CONCLUSION

LRR in primary TKA with patellar resurfacing does not show an improvement in AKP and functional outcomes over patellar resurfacing without release.

LEVEL OF EVIDENCE

I.

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.

A Review of the Lateral Patellofemoral Joint: Anatomy, Biomechanics, and Surgical Procedures

The lateral patellofemoral joint soft tissues contain key structures that surround and balance the joint. These structures can affect joint tracking, stability, and force distribution. It is important to understand the lateral patellofemoral anatomy and biomechanics, and their relationship with patellofemoral instability, anterior knee pain, and osteoarthritis. Lateral-sided surgical procedures such as lateral release, lateral retinacular lengthening, and partial lateral patellar facetectomy can be useful in the treatment of such patellofemoral problems.

Lateral Patellofemoral Ligament Reconstruction With Semitendinosus Allograft in the Setting of Previous Lateral Release

The lateral patellofemoral ligament acts to resist medial displacement of the patella. When medial subluxation occurs, it usually has an iatrogenic cause such as prior lateral release, an over-tightened medial patellofemoral ligament reconstruction, or detachment of the vastus lateralis from the patella. The justification for lateral retinacular release has historically been to address extensor mechanism issues such as imbalance of the mechanism due to increased retinacular tension. We present a Technical Note on the treatment of chronic medial patellar instability due to a previous lateral retinacular release using a soft-tissue reconstruction approach with a semitendinosus allograft.

Treatment of Chronic Dislocated Patella in a Skeletally Mature Down Syndrome Patient: A Case Report

CASE

A 55-year-old man with Down syndrome (DS) suffered from chronic irreducible right patellar dislocation. Imaging studies showed an attenuated appearance of the medial patellar retinaculum, and the tibial tubercle to trochlear groove distance measured 1.6 cm. Right medial patellofemoral ligament reconstruction (MPFLR) and lateral lengthening (LL) with proximalization of the tibial tubercle (PTT) were performed with good surgical outcomes.

CONCLUSION

The combination of MPFLR, LL, and PTT is a viable option for treating a skeletally mature DS patient with patellofemoral instability causing recurrent patellar dislocation.

A National Perspective of Patellar Instability in Children and Adolescents in the United States: MPFL Reconstruction Is Three Times Higher Than the Incidence of Isolated Lateral Release

PURPOSE

The objective was to (1) evaluate any recent changes in the United States in the incidences of medial patellofemoral ligament (MPFL) reconstruction and isolated lateral release for patellar instability in children and adolescents, (2) identify concomitant procedures with MPFL, and (3) report national complication rates after MPFL reconstruction with and without concomitant procedures in children and adolescents.

METHODS

A national database was queried for patients aged 5 to 18 years who underwent operative treatment for patellar instability from 2010 to 2018. Inclusion criteria were either an MPFL reconstruction or lateral release for a diagnosis of patellar instability. Concomitant procedures with MPFL reconstruction assessed were tibial tubercle osteotomy, associated arthroscopic procedures, and lateral release. Changes in incidence in MPFL reconstruction, lateral release and concomitant procedures were assessed. The following postoperative complications were assessed: knee stiffness, infection, patella fracture, and growth arrest or angular deformity.

RESULTS

2,161 patients who underwent MPFL reconstruction and 1,159 patients who underwent isolated lateral release for patellar instability were identified. The incidence of MPFL reconstruction in adolescents from 2010 to 2018 did not change significantly (2010: 7.11, 2018: 5.91, P = .137), while isolated lateral release decreased (2010: 6.06, 2018: 1.83, P < .0001). Concomitant procedures with MPFL reconstruction were common, with arthroscopy being the most frequent (58-67%). The most common complication within 90 days of surgery was patella fracture (0.4% to 2.0%). Infection (0.4% to 1.0%) and growth arrest (0.09% to 0.61%) were the least common. MPFL and arthroscopy had a decreased risk of growth arrest following surgery compared to MPFL alone (P = .038).

CONCLUSIONS

The incidence of MPFL reconstruction remained high from 2010 to 2018, while isolated lateral release decreased during the same time period. Complications after MPFL reconstruction, isolated lateral release, and concomitant procedures were infrequent, with postoperative patella fracture the most common.

LEVEL OF EVIDENCE

IV, case series.

The Role of Lateral Retinacular Release in Preventing Patellofemoral Malalignment in Double-Bundle Anterior Cruciate Ligament Reconstruction: A Randomized Controlled Trial

Background

Loss of internal rotation stability is the major cause of pain after an anterior cruciate ligament reconstruction (ACLR). Many authors described measures to treat this problem to no avail. This is the first study evaluating the role of lateral release with double-bundle ACLR to prevent patellofemoral malalignment after ACLR.

Methods

A total of 100 patients were included in this prospective study between January 2018 and December 2019. We compared single-bundle ACLR (group 1, n = 30), double-bundle ACLR (group 2, n = 30), and double-bundle ACLR with lateral release (group 3, n = 40). Clinical outcome was evaluated with the Kujala score while radiological outcome was evaluated using the tibial tubercle-trochlear groove (TTTG) distance in magnetic resonance imaging. The preoperative and postoperative values were compared.

Results

At the final follow-up of 6–18 months, group 3 showed the lowest TTTG value (6.7 ± 4.69) compared to group 2 (9.1 ± 4.83) and group 1 (11.74 ± 1.76) (p = 0.03). The Kujala score was significantly improved in all groups: from 68.83 to 89.90 in group 1, from 70.02 to 91.23 in group 2, and from 69.71 to 95.05 in group 3 (p = 0.03). Group 3 showed the most superior improvement in the Kujala score (25.34) compare to group 1 (21.07) and group 3 (21.21) (p = 0.012).

Conclusions

Concomitant lateral retinacular release significantly improved the Kujala score. It may serve as a valuable option to overcome patellofemoral pain syndrome in ACLR.

Medial Patellofemoral Ligament Reconstruction with Open Physes

Through this article, the authors aim to summarize the techniques performed on both first time and recurrent skeletally immature patients experiencing patellar dislocation. This article focuses on several key points, such as the importance of medial patellofemoral ligament femoral insertions being distal to the growth plate and performing extensive lateral release and quadricep tendon lengthening in cases of obligatory dislocation. Although acknowledging the procedures discussed cannot be considered for all patients, as individuals with open growth plates may require additional operative time, in many cases these techniques yield high rates of success.

Pedicled Strip of Quadriceps Tendon Graft for Primary Medial Patellofemoral Ligament Reconstruction in Recurrent Patellofemoral Instability: A Systematic Review

PURPOSE

A systematic review of the literature was conducted to ascertain advantages and limitations, update current evidences, and investigate the role of a pedicled quadriceps tendon autograft for primary medio-patellofemoral ligament (MPFL) reconstruction in patients with recurrent patellofemoral instability.

METHODS

The present systematic review was performed according to the PRISMA guidelines. The literature search was conducted in September 2020. All the clinical studies investigating the role of a pedicled strip of quadriceps tendon autograft for primary MPFL reconstruction in patients with recurrent patellofemoral instability were considered for inclusion. Studies investigating the role of MPFL reconstruction combined with additional surgical procedures except for lateral retinacular release were excluded. The methodological quality assessment was performed through the modified Coleman Methodology score.

RESULTS

Data from 9 articles (191 procedures) were retrieved. The mean follow-up was 12 to 38 months. The mean age of the patients was 11.5 to 25.2 years. One hundred twenty of 191 patients were female. All clinical scores showed significant improvement following the procedures. The Kujala score improved of 32.52% points (P < 0.0001), the Lysholm score of 23.74% (P = 0.006), the Tegner scale improved of 8.6% (P = 0.02). Concerning complications, after surgery the apprehension test was positive in 5 of 166 patients, and persistent joint instability was found in 5 of 149 patients. No patient experienced any re-dislocations or underwent reoperations.

CONCLUSIONS

The use of pedicled strip of quadriceps tendon as graft for MPFL reconstruction is a suitable choice in patients with recurrent patellar instability. Although frequently associated with a lateral release, it is unclear whether the latter is necessary for the success of the technique. Appropriately powered randomized controlled trials comparing this graft source to the others commonly used are necessary to at least ascertain the noninferiority of this graft to the others.

LEVEL OF EVIDENCE

IV, Systematic review of Level III-IV studies.