Medial patello-femoral ligament (MPFL) reconstruction using suture anchors fixation: preliminary results

Clinical and radiological outcome of all-suture anchors in shoulder and elbow surgery

Background

All-suture anchors (ASAs) are noted to cause various bone reactions when used in upper limb surgery but clinical implications are unknown.

Methods

88 shoulders and 151 elbows with a mean follow-up of 47.1 ± 17.7 months were invited for follow-up including clinical examination, questionnaires and radiographs. The anchor drill holes were radiographically assessed.

Results

At final follow up, mean DASH was 12.9 ± 13.8 and mean VAS 2.2 ± 2.4 in the shoulder population. In the elbow group mean MEPS was 91.8 ± 12.7 and mean VAS 1.5 ± 1.9. Implant-specific complications were seen in 10 elbow cases but none in the shoulder group. The mean diameter of the 1.4 mm all-suture anchor drill hole was enlarged to 2.5 ± 1.4 mm in the shoulder group and to 2.9 ± 1.0 mm in the elbow group. 50% of the 1.4 mm anchor drill holes showed abnormal morphology but these morphologic changes did not correlate with clinical outcome, complications or reoperation rate.

Discussion

Satisfying clinical outcomes are found in upper limb surgery using ASAs. Various bone changes are seen after implantation of an ASA, but these are not clinically relevant. Long-term consecutive follow-up data is required.

Is the patella apprehension test a valid diagnostic test for patellar instability? A systematic review

Introduction

Patellar instability can arise from a traumatic event with anatomical predisposing factors increasing the risk of dislocation. Accurate diagnosis is required to initiate appropriate treatment. We aimed to evaluate the patella apprehension test (PAT) as a method to diagnose patellar instability.

Methods

The PRISMA diagnostic test accuracy checklist was followed. The review protocol was registered on PROSPERO with registration number CRD42022357898. Electronic databases, currently registered studies, conference proceedings and the reference lists of included studies were searched. A narrative synthesis evaluated the validity of the PAT as a method of diagnosing patellar instability.

Results

A total of 4867 records were screened in the initial search. Of these, 34 articles satisfied the inclusion criteria, assessing 1139 knees of 1046 patients. The PAT was found to have a high sensitivity and specificity. Its intra and inter-rater reliability was highly variable among studies. Studies reporting patellar instability correction following surgery also found a decrease in the number of patients exhibiting a positive PAT.

Conclusion

Current evidence suggests that the PAT has a high sensitivity and specificity. The intra- and inter-rater validities of the PAT are widely variable due to its subjective nature. Thus, though the PAT can be used to provide a provisional clinical diagnosis of patellar instability, formal functional assessment and imaging should be performed to confirm the diagnosis. Further research should explore the association between a positive PAT and anatomical parameters. In addition, studies comparing the accuracy of the PAT and radiological investigations should be performed.

Physeal Sparing Medial Patellofemoral Ligament Reconstruction With Suture Anchor for Femoral Fixation of Graft

Background:

Patellar instability is a common problem in the active pediatric population. Physeal sparing medial patellofemoral ligament (MPFL) reconstruction using a soft suture anchor for femoral graft fixation has the proposed advantages of diminishing volumetric bony removal from the epiphysis, increasing the margin of safety with respect to notch, trochlear, and/or physeal damage, as well as reducing the risk of thermal damage to the physis during socket reaming.

Indications:

MPFL reconstruction is indicated in patients with recurrent patellar instability with MPFL tear or attenuation on magnetic resonance imaging or failure of conservative treatment. Physeal sparing techniques are necessary in the pediatric population to prevent growth disturbance and deformities that can lead to significant long-term disability.

Technique Description:

The patient was placed in supine position. Following examination under anesthesia, diagnostic arthroscopy was performed to assess for patellofemoral chondral defects. The surgical technique required 6 steps: (1) medial patellar dissection, (2) patellar anchor placement with 1.8-mm suture anchors, (3) medial femoral dissection over Schottle’s point, (4) femoral anchor placement using 2.8-mm double loaded anchor, (5) allograft femoral fixation, and (6) allograft patellar fixation. After skin closure, examination under anesthesia was repeated.

Results:

The patient was weight-bearing as tolerated immediately after surgery, using a brace for the first 6 weeks. Rehabilitation progressed from regaining range of motion, strengthening of the operative extremity, and returning to sport activities. In the senior author’s experience using this technique, there have been no recurrent patellar dislocations and no evidence of growth disturbance or angulation. One patient did find that the graft was prominent over the femoral epicondyle and returned to the operating room for debulking at 9 months postoperatively.

Discussion/Conclusion:

In conclusion, we propose that physeal sparing MPFL reconstruction using soft anchors for patellar and femoral fixation offers a simple and safe technique with reproducible anatomic graft placement and favorable clinical outcomes. This technique is technically simple and can be easily learned by surgeons familiar with adult MPFL reconstruction techniques. The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Interference Screws Are Biomechanically Superior to Suture Anchors for Medial Patellofemoral Ligament Reconstruction: A Systematic Review and Meta-Analysis

Purpose

To systematically review the literature to evaluate the biomechanical properties of the interference screw (IS) versus suture anchor (SA) techniques for patellar and femoral fixation of medial patellofemoral ligament (MPFL) reconstruction.

Methods

A systematic review was performed by searching PubMed, the Cochrane library, and Embase using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that analyzed the biomechanical properties of IS and SA techniques for MPFL reconstruction. The search phrase implemented was “medial patellofemoral ligament reconstruction biomechanics.” Evaluated outcomes included ultimate load to failure (N), stiffness (N/mm), and mode of failure. Forest plots were created for statistical analysis and heterogeneity was assessed via I² statistic.

Results

Six studies met inclusion criteria, including a total of 108 cadaveric specimens, for MPFL patellar fixation, and 3 studies met inclusion criteria, including a total of 50 cadaveric specimens, for MPFL femoral fixation. Pooled analysis from 5 studies reporting on stiffness for MPFL patellar fixation revealed a statistically significant difference in favor of IS compared with SA (P = .007). Pooled analysis from 3 studies reporting on ultimate load to failure of femoral fixation revealed a statistically significant difference in favor of IS compared with SA (P = .043).

Conclusions

The use of IS was associated with a greater stiffness compared with the use of SA in MPFL patellar fixation, but there was no difference in load to failure between IS and SA. The use of IS was associated with a greater load to failure compared with the use of SA in MPFL femoral fixation, but there was no difference in stiffness between IS and SA.

Clinical Relevance

There have been multiple individual biomechanical studies conducted comparing IS and SA fixation for MPFL patellar and femoral fixation; however, they have yielded conflicting results, with small sample sizes. Pooling the data from these studies in a meta-analysis may allow for more meaningful biomechanical data to coincide with the existing, albeit scarce, clinical data, this may help to inform clinical decision making for surgeons managing these injuries.

Interference screws vs. suture anchors for isolated medial patellofemoral ligament femoral fixation: A systematic review

PURPOSE

The present study aimed to systematically review and compare 2 femoral autograft fixation techniques, namely, interference screws and suture anchors, for isolated medial patellofemoral ligament reconstruction in patients with recurrent patellofemoral instability at mid- to long-term follow-up.

METHODS

A literature search was performed in September 2020. All studies reporting the outcomes of primary isolated medial patellofemoral ligament reconstruction for recurrent patellofemoral instability were considered for inclusion. Only studies reporting the type of femoral autograft fixation under examination were considered. Studies reporting data from patients with elevated tibial tuberosity-tibial groove, patella alta, and/or Dejour's trochlear dysplasia types C and D, were not included. Only articles reporting data with a minimum follow-up period of 18 months were considered.

RESULTS

Data from 19 studies (615 patients) were retrieved. The overall age was 24.4 ± 6.7 years (mean ± SD). The mean follow-up was 46.5 ± 20.9 months. There were 76 patients in the anchor group and 539 in the screw group. Comparability was found with regard to age and follow-up duration between the 2 study groups. There was comparability between the Kujala, Lysholm, and Tegner scores at baseline. At the last follow-up, no worthy differences were found in terms of mean Kujala (+2.1%; p = 0.04), Lysholm (+1.7%; p = 0.05), and Tegner (+15.8%; p = 0.05) scores. Although complications occurred almost exclusively in the screw cohort, no statistically significant difference was found.

CONCLUSION

Femoral autograft fixation through interference screws or suture anchors report similar clinical scores and rate of apprehension test, persistent joint instability, re-dislocations, and revisions. These results must be interpreted within the limitations of the present study.

Interference Screw Versus Suture Anchors for Femoral Fixation in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Study

Background:

Femoral-sided graft fixation in medial patellofemoral ligament (MPFL) reconstruction is commonly performed using an interference screw (IS). However, the IS method is associated with several clinical disadvantages that may be ameliorated by the use of suture anchors (SAs) for femoral fixation.

Purpose:

To compare the load to failure and stiffness of SAs versus an IS for the femoral fixation of a semitendinosus autograft in MPFL reconstruction.

Study Design:

Controlled laboratory study.

Methods:

Based on a priori power analysis, a total of 6 matched pairs of cadaveric knees were included. Specimens in each pair were randomly assigned to receive either SA or IS fixation. After an appropriate reconstruction procedure, the looped end of the MPFL graft was pulled laterally at a rate of 6 mm/s until construct failure. The best-fit slope of the load-displacement curve was then used to calculate the stiffness (N/mm) in a post hoc fashion. A paired t test was used to compare the mean load to failure and the mean stiffness between groups.

Results:

No significant difference in load to failure was observed between the IS and the SA fixation groups (294.0 ± 61.1 vs 250.0 ± 55.9; P = .352), although the mean stiffness was significantly higher in IS specimens (34.5 ± 9.6 vs 14.7 ± 1.2; P = .004). All IS reconstructions failed by graft pullout from the femoral tunnel, whereas 5 of the 6 SA reconstructions failed by anchor pullout.

Conclusion:

In this biomechanical study using a cadaveric model of MPFL reconstruction, SA femoral fixation was not significantly different from IS fixation in terms of load to failure. The mean load-to-failure values for both reconstruction techniques were greater than the literature-reported values for the native MPFL.

Clinical Relevance:

These results suggest that SAs are a biomechanically viable alternative for femoral-sided graft fixation in MPFL reconstruction.

Return to Play After Medial Patellofemoral Ligament Reconstruction: A Systematic Review

BACKGROUND

Medial patellofemoral ligament (MPFL) reconstruction is being performed more frequently in athletes experiencing recurrent patellar instability.

PURPOSE/HYPOTHESIS

The purpose was to systematically review the evidence in the orthopaedic sports medicine literature to determine both the rate and timing of return to play after MPFL reconstruction and the rate of further patellar instability. Our hypothesis was that there would be a high rate of return to play after MPFL reconstruction.

STUDY DESIGN

Systematic review.

METHODS

A systematic literature search was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, which utilized EMBASE, MEDLINE, and the Cochrane Library databases. Inclusion criteria for literature included clinical studies reporting on return to play after MPFL reconstruction. Rate of return to play, level of return, timing of return, rate of recurrent instability, and patient-reported outcomes were evaluated. Statistical analysis was performed using SPSS.

RESULTS

Our review found 27 studies including 1278 patients meeting our inclusion criteria. The majority of patients were women (58%), and the total group had a mean age of 22.0 years and a mean follow-up of 39.3 months. The overall rate of return to play was 85.1%, with 68.3% returning to the same level of play. The average time to return to play was 7.0 months postoperatively. The rate of recurrent instability events following reconstruction was 5.4%. There was an improvement in both mean visual analog scale, pain scores (preoperative: 4.3, postoperative: 1.6) and Tegner activity scores (preoperative: 4.8, postoperative: 5.5).

CONCLUSION

The overall rate of return to play was high after MPFL reconstruction for the treatment of recurrent patellar instability. However, a relatively high percentage of those patients were unable to return to their preoperative level of sport. Additionally, there was a moderate time taken to return to play, at approximately 7 months after the procedure.

Medial Patellofemoral Ligament Reconstruction in Traumatic Patellar Dislocation without Patellar Fixation

Acute traumatic patellar dislocation is a common injury, and spontaneous reduction may occur at the time of injury or may be reduced at the field of the accident by someone. It may be associated with osteochondral fractures and rupture of medial patellar stabilizers leading to recurrent patellar instability. The aim of this prospective study was to evaluate the outcomes of medial patellofemoral (PF) ligament (MPFL) reconstruction in recurrent traumatic patellar dislocation. Forty-five patients presented with PF instability as a result of traumatic rupture MPFL with normal patellar tracking underwent MPFL reconstruction without patellar fixation hardware through two parallel transpatellar tunnels and one screw in femoral tunnel. All patients were evaluated clinically preoperatively and at a minimum follow-up of 24 months, and International Knee Documentation Committee (IKDC) and Kujala scores were used to assess the clinical results. All patients were available for evaluation at a minimum of 24 months (up to 36 months). The mean age of these patients at the time of surgery was 22.82 years (range: 18-34 years). All patients gave history of trauma of their knees. Mean IKDC scale showed significant improvement as it rose from 47.17 preoperatively to 77.94 postoperatively, and mean Kujala score rose from 53.88 preoperatively to 86.24 postoperatively (p < 0.001). No recurrence of dislocation was recorded. Only three patients had mild atrophy of thigh and one patient had some difficulty in jumping. Reconstruction of MPFL by this method provides good clinical result in the treatment of PF instability by using autologous graft (semitendinosus and gracilis). Less hardware were used with less complications.

Anchor-Based Femoral Fixation for Physeal-Sparing Medial Patellofemoral Ligament Reconstruction: A Time-Zero Biomechanical Comparison With Tenodesis Screw Fixation

BACKGROUND

Open physes and trochlear/notch geometries in pediatric patients limit the safe corridor for femoral interference screw graft fixation during medial patellofemoral ligament (MPFL) reconstruction. Accordingly, interest is increasing in anchor-based fixation, but biomechanical validation is deficient.

PURPOSE

To compare anchor-based and tenodesis screw femoral fixation of MPFL grafts in a time-zero biomechanical model.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty-seven fresh-frozen porcine distal femurs were potted for testing in an electromechanical load frame, while bovine tendons were used for MPFL grafts. Reconstructions were performed with 1 of 3 femoral fixation strategies: 4.5-mm biocomposite double-loaded threaded anchor (DLA group), 3.9-mm biocomposite knotless threaded anchor (KA group), or traditional 7 × 23-mm biocomposite tenodesis screw (TS group). For testing, femoral specimens were oriented and secured in the mechanical testing apparatus such that actuator tensile pull re-created the normal MPFL trajectory. Specimens underwent 10 cycles of 5- to 15-N loading at 1-Hz preconditioning, followed by 1000 cycles of 10- to 50 N-loading at 1 Hz. After cyclic loading, all specimens were loaded to failure at 305 mm/min. The average cyclic construct stiffness, displacement, and load-to-failure data between the 3 groups were compared using analysis of variance (ANOVA) with the significance level set at P < .05.

RESULTS

Average cyclic construct stiffnesses were comparable across groups per repeated-measures ANOVA analysis: 68.3 ± 6.3, 71.4 ± 6.4, and 74.3 ± 7.9 N/mm for TS, DLA, and KA groups, respectively (at cycle 1000). Average construct displacements at cycles 100 and 1000 were significantly less in the anchor versus tenodesis screw groups per ANOVA and Tukey post hoc analysis: 7.7 ± 4.2 mm for the TS group versus 3.7 ± 0.4 and 4.3 ± 0.6 mm for the DLA and KA groups, respectively (at cycle 1000). There was no significant difference in ultimate failure loads between the anchor and tenodesis screw groups, but 3 of 9 TS constructs failed at loads below the average failure load of the native MPFL.

CONCLUSION

Compared with the tenodesis group, anchor-based fixation produced constructs with equivalent cyclic stiffnesses, improved load-displacement characteristics, and had less failure load variability in the porcine cadaveric model.

CLINICAL RELEVANCE

Femoral fixation of the MPFL graft with a single anchor (4.5 or 3.9 mm threaded) is a viable alternative to traditional tenodesis screw fixation.

Physeal-Sparing Medial Patellofemoral Ligament Reconstruction With Suture Anchor for Femoral Graft Fixation

Patellar instability is a common problem in the active pediatric population. When nonoperative treatment of the instability fails, growth-respecting surgical stabilization techniques are required. As the incidence of medial patellofemoral ligament (MPFL) reconstruction has increased, techniques have improved to avoid physeal injury to the distal femur. These techniques are technically demanding because of the small size of the distal femoral epiphysis in children, as well as the relatively large socket size (7-8 mm in diameter, >20 mm in length) required for sound fixation with a tenodesis screw as originally described. The size of the femoral tunnel for interference fixation puts the surrounding structures at risk of damage. We present a modification of the epiphyseal socket technique for anatomic growth-sparing MPFL reconstruction using a small soft anchor for femoral graft fixation. This has the proposed advantages of diminishing volumetric bony removal from the epiphysis; increasing the margin of safety with respect to notch, trochlear, and/or physeal damage; and reducing the risk of thermal damage to the physis during socket reaming. This technique is technically simple and can be easily learned by surgeons familiar with adult MPFL reconstruction techniques.

Clinical Outcomes After Medial Patellofemoral Ligament Reconstruction Using Transosseous Sutures Versus Suture Anchors: A Prospective Nonrandomized Controlled Trial

Background

Patellar instability remains a challenging problem for orthopaedic surgeons. Recurrent patellar instability is traditionally treated with medial patellofemoral ligament (MPFL) reconstruction using a suture anchor or bone tunnel technique. Although the use of transosseous sutures was recently described for MPFL reconstruction, relevant clinical data have not been reported.

Purpose/Hypothesis

The purpose of this study was to compare a new transosseous suture fixation technique with the suture anchor technique for MPFL reconstruction. The hypothesis was that reconstruction with transosseous sutures would show similar clinical results to reconstruction with suture anchors.

Study Design

Cohort study; Level of evidence, 2.

Methods

There were 65 patients with recurrent lateral patellar dislocations from January 2014 to December 2016 who were included in this prospective nonrandomized controlled trial. In total, 31 patients underwent MPFL reconstruction with suture anchors at the patella site (suture anchor group), while the other 34 patients underwent MPFL reconstruction with transosseous sutures (transosseous suture group). The main outcome variable (patellar redislocation) was recorded at follow-up (range, 25-60 months). The International Knee Documentation Committee (IKDC) score, Kujala score, range of motion, congruence angle, patellar tilt, redislocation rate, and complications were collected preoperatively and/or postoperatively.

Results

No recurrent dislocations or other complications were observed in any of the patients. No significant differences were found at follow-up between the suture anchor and transosseous suture groups for subjective IKDC score, Kujala score, congruence angle, patellar tilt, redislocation rate, or range of motion.

Conclusion

This short-term study showed that after MPFL reconstruction (suture anchors or transosseous sutures), patellar stability could be restored. With the numbers available, no significant differences in outcome scores were observed between patients in the transosseous suture and suture anchor groups.

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

BACKGROUND

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

HYPOTHESIS

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

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

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

RESULTS

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

CONCLUSION

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

Isolated medial patellofemoral ligament reconstruction significantly improved quality of life in patients with recurrent patella dislocation

PURPOSE

The purpose of this study was to measure the improvement in quality of life (QoL) following isolated anatomical double-bundle medial patellofemoral ligament reconstruction.

METHODS

This is a single-centre, prospective study of 56 consecutive patients (57 knees) who underwent isolated MPFL reconstruction between 2014 and 2017. Functional outcome and QoL were assessed with the Kujala score and the EQ-5D-3L questionnaire, respectively. Objective outcomes were obtained through clinical examination at the latest follow-up assessing redislocation rate, patella apprehension test, patellar tilt, pain and range of motion.

RESULTS

The median Kujala score increased from 60 (range 31-96) to 92 (range 34-100) at latest follow-up (p < 0.001). The median EQ-5D index also increased, from 0.69 (range 0.10-1) at baseline to 1 (range 0.16-1) at latest follow-up (p < 0.001), as well as the median EQ-5D VAS from 75 (range 20-95) to 92 (range 40-100) (p < 0.001). Four dimensions of the EQ-5D were significantly improved except for the anxiety/depression scores. Female patients reported lower scores at baseline and at latest follow-up, for all three outcomes (Kujala, EQ-5D index, EQ-5D VAS), however there was no evidence that gender negatively impacted on the benefit of surgery. The re-dislocation rate was 0%. Apprehension and patellar tilt test were negative in all patients and no flexion deficit was identified at latest follow-up. Two patients had tenderness along the reconstruction requiring femoral screw removal in one of them.

CONCLUSIONS

Isolated anatomical double-bundle aperture MPFL reconstruction, offered significantly improved short-term QoL along with excellent functional outcome. Female patients scored lower, but this did not affect the overall outcome. Including QoL tools in the assessment of ligament reconstruction operations, such as the MPFL, can provide more accurate understanding of the overall patient benefit.

LEVEL OF EVIDENCE

II.

Patellar Redislocation Rates and Clinical Outcomes After Medial Patellofemoral Ligament Reconstruction: Suture Anchor Versus Double Transpatellar Tunnel Fixation

BACKGROUND

Few studies to date have compared clinical outcomes in patients who have undergone medial patellofemoral ligament (MPFL) reconstruction using the suture anchor and double transpatellar tunnel fixation methods. This meta-analysis therefore compared the clinical results, including the patellar redislocation rate and improvement in functional scores, of suture anchor and double transpatellar tunnel fixation.

HYPOTHESIS

The recurrence rate and improvement in functional outcomes after surgery would be similar using the suture anchor and double transpatellar tunnel fixation methods.

STUDY DESIGN

Meta-analysis.

METHODS

Studies evaluating MPFL reconstruction using either the suture anchor or double transpatellar tunnel technique for patellar site fixation were included if they reported the patellar redislocation rate after surgery and/or validated patient-reported outcomes such as the Kujala and Lysholm scores.

RESULTS

Twenty-one studies were included in this meta-analysis. The mean patellar redislocation rates were similar using the suture anchor (3.2% [95% CI, 1.6%-6.2%]) and double transpatellar tunnel (3.4% [95% CI, 2.1%-5.4%]) techniques ( P = .879). The mean improvement in the Kujala score from before to after MPFL reconstruction was greater using the suture anchor (37.2 [95% CI, 31.1-43.4]) method than the double transpatellar tunnel method (28.7 [95% CI, 21.2-36.1]) ( P = .018). However, the mean improvement in the Lysholm score did not differ significantly using the 2 techniques.

CONCLUSION

The patellar redislocation rate did not differ significantly in patients who underwent MPFL reconstruction using the suture anchor and double transpatellar tunnel fixation methods. The suture anchor fixation method, however, resulted in a greater degree of improvement in patient-reported outcomes.

Proximal medial patellar restraints and their surgical reconstruction

Reconstruction of the medial patellofemoral ligament (MPFL) has been increasing as a surgical solution for treatment of recurrent lateral patellofemoral dislocation. Recent attention has been given to fibers extending from the femur to the quadriceps tendon, proximal to the MPFL, termed the medial quadriceps tendon-femoral ligament. This article briefly reviews the proximal medial patellar restraints and surgical procedures for their reconstruction.

Return-to-Play Guidelines After Medial Patellofemoral Ligament Surgery for Recurrent Patellar Instability: A Systematic Review

BACKGROUND

Medial patellofemoral ligament (MPFL) reconstruction and repair continue to gain acceptance as viable treatment options for recurrent patellar instability in patients who wish to return to sports after surgery. Return-to-play guidelines with objective or subjective criteria for athletes after MPFL surgery, however, have not been uniformly defined.

PURPOSE

To determine whether a concise and objective protocol exists that may help athletes return to their sport more safely after MPFL surgery.

STUDY DESIGN

Systematic review.

METHODS

The clinical evidence for return to play after MPFL reconstruction was evaluated through a systematic review of the literature. Studies that measured outcomes for isolated MPFL surgery with greater than a 12-month follow-up were included in our study. We analyzed each study for a return-to-play timeline, rehabilitation protocol, and any measurements used to determine a safe return to play after surgery.

RESULTS

Fifty-three studies met the inclusion criteria, with a total of 1756 patients and 1838 knees. The most commonly cited rehabilitation guidelines included weightbearing restrictions and range of motion restrictions in 90.6% and 84.9% of studies, respectively. Thirty-five of 53 studies (66.0%) included an expected timeline for either return to play or return to full activity. Ten of 53 studies (18.9%) in our analysis included either objective or subjective criteria to determine return to activity within their rehabilitation protocol.

CONCLUSION

Most studies in our analysis utilized time-based criteria for determining return to play after MPFL surgery, while only a minority utilized objective or subjective patient-centric criteria. Further investigation is needed to determine safe and effective guidelines for return to play after MPFL reconstruction and repair.

A new minimally invasive surgical technique for medial retinaculum repair following traumatic patellar dislocation

A new surgical method is introduced offering a less invasive approach to reattach the medial retinaculum following acute patellar dislocation. This retrospective analysis comprised 12 cases of medial retinacular repair in 10 patients. The surgical technique achieved reinforced reattachment of the torn region of the medial retinaculum for improved patellar support and stabilization. During follow-up, no recurrent patellar dislocations occurred, except where one patient reported a subjective feeling of patellar dislocation. The average Kujala score for our sample group after 2 years was 89.2. A plethora of methods are described in the literature to repair a tear to the medial patellofemoral ligament, which attaches at the superomedial patella. However, it is our contention that traumatic patellar dislocation invariably results in osteochondral avulsion at the inferomedial patella, refuting medial patellofemoral ligament involvement, and, rather, implicating the inferior aspect of the deep layer of medial retinaculum. Our surgical technique enables stable fixation of the region, decreasing the rate of recurrent dislocations. No grafts are used, permitting tendinous and ligamentous anatomy to remain intact. We further postulate that performing a CT examination preoperatively may reduce time between diagnosis and surgery, in addition to locating fracture sites more precisely.