Medial Patellofemoral Ligament Repair Research Articles

A Single Incision Technique for Medial Patellofemoral Ligament Repair with Augmentation Using a Reinforced Bio-Inductive Implant

Patella dislocations and resultant recurrent instability commonly occur. Surgery for patella dislocation is indicated after subsequent dislocation or after an initial dislocation with articular cartilage injury of the patella or femur. The strength of an isolated medial patellofemoral ligament (MPFL) repair has been shown to be insufficient to prevent recurrent dislocation. Multiple different techniques to augment the MPFL repair using various autologous and allografts, as well as high tensile strength sutures or synthetic ligaments have been developed. Most of the techniques use two incisions: one near the patella and the other by the medial femoral condyle. The purpose of this study is to demonstrate a single incision technique for MPFL repair with augmentation using a reinforced bio-inductive (RBI) implant. The single-incision technique does have advantages over the two-incision techniques. Furthermore, the RBI implant is easily reproducible docked into the patella sockets without difficulty and has an initial inherent strength comparable to the semitendinosus. The RBI heals to bone and allows for infiltration of the patient’s own cells which strengthens the augmentation over time.

Medial Patellofemoral Ligament Augmented With a Reinforced Bioinductive Implant Is Biomechanically Similar to the Native Medial Patellofemoral Ligament at Time Zero in a Cadaveric Model

To biomechanically compare primary medial patellofemoral ligament (MPFL) repair (MPFLr) augmented with a reinforced bioinductive implant (RBI) to the native MPFL ligament and a semitendinosus (semi-T) MPFL reconstruction (MPFLR) at time zero. Four fresh-frozen matched pair cadavers (8 knees) were used to biomechanically compare the native MPFL to augmented MPFLr (n= 4) and semi-T MPFLR (n= 4). The native MPFL (n= 8) was isolated, preserving the femoral and patellar attachments, and pulled to failure. The semi-T was harvested from 1 of the matched pairs and whipstitched, as was a 250-mm× 5-mm RBI. A standard double-bundle docking technique was utilized. The patella was potted and mechanically pulled parallel to the transverse axis until failure in both cohorts. Cyclic creep, load and displacement at failure, failure mode, and stiffness were recorded. Failure load was highest in the RBI with repair group (287 ± 130 N) compared to the native MPFL (219 ± 64 N) and the semi-T group (84 ± 29 N). No statistically significant difference in failure load between the RBI augmentation with repair group and the native ligament (P= .19) were found. The semi-T reconstruction group failed at the least amount of displacement (7.93 ± 3.4 mm) compared to the native MPFL (20.9 ± 9 mm) (P < .01) and the RBI with repair group (33.2 ± 17.7 mm) (P < .02). At 10 mm of displacement, the RBI group (8.3 ± 1.2 N/mm) demonstrated stiffness in the midrange compared to the native MPFL (14.1 ± 7.1 N/mm). Early anchor/tendon pullout failure on the patella side was noted in the semi-T group compared to the RBI group. One reconstruction was excluded from analysis due to poor bone quality. No statistically significant difference was seen between the augmented MPFL repair and the native MPFL in load-to-failure testing. The augmented MPFL repair was observed to have biomechanical properties similar to the native MPFL. MPFLr with RBI augmentation provided consistent stiffness at clinically relevant displacement. Primary MPFL repair and reconstruction using the semi-T graft, while effective, are nevertheless imperfect procedures. MPFL repair has been shown to have higher instability recurrence rates, while the stiffness profile of MPFLR with semi-T is higher than the native MFPL and may lead to knee stiffness, loss of motion, or cartilage damage. The results of this time-zero biomechanical study indicate that the use of an RBI for augmentation of a primary MPFL repair may be a viable alternative to traditional MPFL repair or reconstruction using a semi-T graft.

Patellofemoral Instability Part II: Surgical Treatment.

Treatment of patellofemoral instability in skeletally mature patients remains an important area of clinical and research interest. Both nonsurgical and surgical interventions are used to treat the underlying causes. Surgical management is the mainstay of treatment of recurrent PFI that fails nonsurgical treatment, and it is broadly classified into bony and soft-tissue procedures. Proximal bony procedures include femoral trochleoplasty, derotational osteotomies, and coronal alignment correction of the femur. Distal bony procedures include tibial tubercle transfer and derotational (supratubercle and infratubercle) osteotomies. Soft-tissue procedures consist of medial patellofemoral ligament repair or reconstruction and lateral lengthening procedures. This article is the second part of our two-article review on PFI, which focuses on surgical treatment options, their indications, outcomes, and potential complications.

Comparison of Failure Rates at Long-term Follow-up Between MPFL Repair and Reconstruction for Recurrent Lateral Patellar Instability.

The medial patellofemoral ligament (MPFL) is the primary soft tissue restraint to lateral patellar translation and is often disrupted by lateral patellar dislocation. Surgical management for recurrent patellar instability focuses on restoring the MPFL function with repair or reconstruction techniques. Recent studies have favored reconstruction over repair; however, long-term comparative studies are limited. To compare long-term clinical outcomes, complications, and recurrence rates of isolated MPFL reconstruction and MPFL repair for recurrent lateral patellar instability. Cohort study; Level of evidence, 3. A total of 55 patients (n = 58 knees) with recurrent lateral patellar instability were treated between 2005 and 2012 with either MPFL repair or MPFL reconstruction. The exclusion criteria were previous or concomitant tibial tubercle osteotomy or trochleoplasty and follow-up of <8 years. Pre- and postoperative descriptive, surgical, imaging, and clinical data were recorded for each patient. MPFL repair was performed on 26 patients (n = 29 knees; 14 women, 15 men), with a mean age of 18.4 years. MPFL reconstruction was performed on 29 patients (n = 29 knees; 18 women, 11 men), with a mean age of 18.2 years. At a mean follow-up of 12 years (range, 8.3-18.9 years), the reconstruction group had a significantly lower rate of recurrent dislocation compared with the repair group (14% vs 41%; P = .019). There were no differences in the number of preoperative dislocations or tibial tubercle-trochlear groove distance. The reconstruction group had significantly more time from initial injury to surgery compared with the repair group (median, 1460 days vs 627 days; P = .007). There were no differences in postoperative Tegner, Lysholm, or Kujala scores at the final follow-up. In addition, no statistically significant differences were detected in return to sport (RTS) rates (repair [81%] vs reconstruction [75%]; P = .610) or reoperation rates for recurrent instability (repair [21%] vs reconstruction [7%]; P = .13). MPFL repair resulted in a nearly 3-fold higher rate of recurrent patellar dislocation (41% vs 14%) at the long-term follow-up compared with MPFL reconstruction. Given this disparate rate, the authors recommend MPFL reconstruction over repair because of the lower failure rate and similar, if not superior, clinical outcomes and RTS.

Medial Patellofemoral Ligament Repair: Still a Relevant Treatment for Patellar Instability?

Medial Patellofemoral Ligament Repair: Still a Relevant Treatment for Patellar Instability?

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.

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. 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. 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). 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.

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.

Cadaveric Study to Define the Anatomy of the Medial Patellofemoral Ligament (MPFL) and Its Variant Patterns.

The medial patellofemoral ligament (MPFL) is one of the major soft tissue stabilizers on the medial side of the knee joint, extending from the medial condyle of the femur to the medial aspect of the patella. Different kinds of literature described different sizes and different origins and insertions of MPFL. Injury of MPFL causes patellar instability and dislocation.We reported the anatomy and morphology of MPFL and its implications in the repair of MPFL. The aim of the study was also to look at the variant forms of the MPFL. Methodology: A total of 40 lower limbs fixed in formalin were dissected to study the MPFL of the knee. After reflecting the deep fascia and retinaculum on the medial side of the knee joint the MPFL was exposed. For better learning the lower medial part of vastus medialis was reflected, so that the part of MPFL undercover was exposed. Different forms of MPFL were seen like two straps 12.5%, broad rectangle 20%, and triangular shaped 67.5% MPFL.The origin of MPFL was found between the adductor tubercle and medial epicondyle of the femur and insertion was seen extending from the proximal medial half of the patella to the tendinous aponeurosis of vastus medialis obliquus (VMO) and vastus intermedius muscle (VIM). This is the first study that described three variant patterns of MPFL in accordance with their morphological appearance. This knowledge will be helpful to the surgeons for easy identification and repair of the MPFL.

Treatment of Sports Injuries in Orthopedic Surgery: Recent Advances

This article reviews the most recent advances in the literature regarding orthopedic surgery for sports injuries. For large-to-massive rotator cuff tears, non-surgical treatment yielded superior results at three months to surgical treatment, although surgical treatment provided better results over time. Arthroscopic partial repair without a posterior interval slide yielded superior results to complete arthroscopic rotator cuff repair with a posterior interval slide. Graft bridging yielded superior results to superior capsular reconstruction. In first-time shoulder dislocations, arthroscopic Bankart repair has yielded superior results to arthroscopic washout. In high-grade acromioclavicular separation, a single clavicle tunnel tendon graft construct is preferable to a double tunnel construct. In femoroacetabular impingement, patients treated with hip arthroscopy had superior short-term results to those treated with physiotherapy alone. The odds of needing anterior cruciate ligament (ACL) graft revision were 2.1-fold higher for patients using a hamstring autograft than those using a patellar bone-tendon-bone (BTB) autograft. The use of a patellar tendon graft reduced the risk of graft rupture. The return-to-sports rate was higher for patients who underwent surgery with a BTB autograft than those with an autograft hamstring. The combination of lateral extra-articular tenodesis and ACL reconstruction-ACLR (single-bundle hamstring autograft) decreased the risk of ACLR failure after two years of follow-up. In complete mid-substance ACL injuries, the bridge-enhanced ACL repair technique resulted in similar outcomes to autograft ACLR. Fresh-frozen allografts have been a good alternative to autografts in ACLR. In posterior medial meniscal root tears, root repair was associated with less arthritic progression than non-surgical treatment and partial meniscectomy. Medial patellofemoral ligament (MPFL) reconstruction has provided better results than MPFL repair in patellofemoral instability.

Lateral Patellar Instability.

Patellar instability represents a common problem with an evolving understanding and multifactorial pathoetiology. Treatment plans should be based on the identification of contributing anatomical factors and tailored to each individual patient. Risks for recurrent instability are dependent on several patient-specific factors including patella alta, increased tibial tubercle-to-trochlear groove (TT-TG) distance, trochlear dysplasia, younger skeletal age, and ligamentous laxity. Cartilage or osteochondral lesions and/or fractures are commonly observed in first-time patellar dislocation, and magnetic resonance imaging (MRI) should be strongly considered. Advanced imaging modalities, such as computed tomography (CT) or MRI, should also be obtained preoperatively to identify predisposing factors and guide surgical treatment. Medial patellofemoral ligament (MPFL) reconstruction with anatomical femoral tunnel positioning is associated with lower recurrence rates compared with MPFL repair and has become a common and successful reconstructive surgical option in cases of instability. Lateral retinacular tightness can be addressed with lateral retinacular release or lengthening, but these procedures should not be performed in isolation. Tibial tubercle osteotomy is a powerful reconstructive tool in the setting of underlying skeletal risk factors for instability and can be of particular benefit in the presence of increased TT-TG distance (>20 mm), and/or in the setting of patella alta. The indications for trochleoplasty are still developing along with the clinical evidence, but trochleoplasty may be indicated in some cases of severe trochlear dysplasia. Several surgical techniques have indications in specific clinical scenarios and populations, and indications, risks, and benefits to each are progressing with our understanding. Combined femoral derotational osteotomy and MPFL reconstruction can be considered for patients with a femoral anteversion angle of >30° to improve patient outcomes and reduce recurrence rates.

Patellar dislocation recurrence after pediatric MPFL reconstruction: Bone tunnels and soft tissues versus suture anchors and interference screw

BackgroundSeveral Medial Patellofemoral Ligament (MPFL) reconstruction techniques have been developed, and those with soft tissue fixation are often preferred in children because they allow the growth cartilage to be preserved. Nevertheless, the recurrence rate of patellar dislocation varies widely from one series to another, with no clear superiority of one technique in the pediatric setting. The objectives of this study were to compare the results of two tendon graft fixation techniques (tendon-tendon fixation and anchor-screw fixation) by analyzing: 1) the rate of patellar dislocation recurrence, 2) clinical outcomes, 3) tourniquet time and 4) complication rate. HypothesisThe two tendon graft fixation techniques used in MPFL reconstruction are equivalent in terms of the patellar dislocation recurrence rate. Patients and methodsThis is a retrospective comparative study including 57 patients with a median age of 14 years (12–15 years) who underwent MPFL reconstruction between 2016 and 2020. The tendon graft was fixed upon itself, after passing through a patellar tunnel (Group A: tendon-tendon fixation; n=29) or by two anchors and an interference screw (Group B: anchor-screw fixation; n=28). The preoperative radiographic data were comparable in the two groups: patellar height [A: 1.3 (interquartile range (IQR): 1.2–1.4) / B: 1.2 (IQR: 1–1.4) (p=0.21)], tibial tuberosity to trochlear groove (TTTG) distance [A: 16 (IQR: 13–19) / B: 13.5 (IQR: 11.5–18.8) (p=0.12)], patellar tilt [A: 25 (IQR: 20–35) / B: 24.5 (IQR: 21–32) (p=0.93)]. For each technique, the rate of patellar dislocation recurrence, clinical and functional results (Kujala score, Marx activity score, Lille patellofemoral score), complications (pain, stiffness, revision) were analyzed. In addition to MPFL repair, 13 patients (2 in Group A, 11 in Group B) underwent additional orthopedic procedures to enhance patellar stability. Resultsno patients were lost to follow-up and the median follow-up was 30 months (IQR: 20–38). The dislocation recurrence rate was higher in Group A, 6.9% (2/29) compared to none in Group B. The clinical results were comparable for the two groups with a Kujala score [A: 94 (IQR: 89–100) / B: 92 (IQR: 87.5–94.5) (p=0.12)]; Marx score [A: 10 (IQR: 7–11) / B: 9.5 (IQR: 7.5–12) (p=0.89)] and Lille patellofemoral score [A: 97 (IQR: 91–100) / B: 94 (IQR: 90–98) (p=0.21)]. The tourniquet time was shorter in Group A than in Group B, 61minutes (IQR: 52-71) versus 85minutes (IQR: 55-115) (p=0.024) excluding additional orthopedic procedures. The complication rate was 17.2% (5/29) in Group A (dislocation n=2, stiffness n=2, ATT (anterior tibial tuberosity) revision with screw removal n=1) and 10.7% (3/28) in B (pain n=1, ATT revision with screw removal n=2) (p=0.35). ConclusionClinically, anchor-screw fixation appears to reduce the risk of patellar dislocation recurrence but this could not be statistically tested. On the other hand, the two techniques are comparable in terms of the functional results. Level of evidenceIII; retrospective case-control study.

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.

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. 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. 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 10studies 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. 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. IV.

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

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. 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). 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. 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 IV, systematic review of Level I-IV.

All-arthroscopic Knee Patellofemoral Ligament Repair

Patellar dislocations are common injuries in the pediatric and adolescent population, with an estimated mean incidence of 42/100,000 person-years. The medial patellofemoral ligament is the most important structure preventing lateral patellar translation, whereas its patellar attachment is frequently damaged after patellar dislocations. This technical note presents an all-arthroscopic medial patellofemoral ligament repair technique suggested after a first episode of patellar dislocation.

Paper 54: MPFL Repair has a Higher Failure Rate at Long-term Follow-up compared to MPFL Reconstruction for Recurrent Patellar Instability

Objectives:The medial patellofemoral ligament (MPFL) is the primary soft tissue restraint to lateral patellar translation and is often disrupted with a lateral patellar dislocation. Surgical management for recurrent patellar instability focuses on restoring MPFL function with repair or reconstruction techniques. Recent studies have favored reconstruction over repair, but no long-term, comparative studies are available in the literature.Methods:A total of 55 patients (58 knees) with recurrent lateral instability were treated between 2005 and 2012 with either MPFL repair or MPFL reconstruction. Exclusion criteria included prior or concomitant tibial tubercle osteotomy or trochleoplasty, and follow-up less than 8 years. Pre- and post-operative demographic, surgical, imaging and clinical data were recorded for each patient.Results:MPFL repair was performed on 26 patients (29 knees; 14 females, 15 males) at a mean age of 19.1 years. MPFL reconstruction was performed on 29 patients (29 knees; 18 females, 11 males) at a mean age of 18.2 years. Mean follow-up was 12.0 years (range 8.3-18.9). The reconstruction group had a significantly lower rate of recurrent dislocation compared to the repair group (14% vs 41%, p=0.019) at final follow up. There were no differences in the number of pre-operative dislocations (greater than or less than 3), degree of patellar facet chondromalacia, TT-TG distance, or Tegner scores. The reconstruction group had significantly more time from injury to surgery compared to the repair group (median, 1,460 days vs 627 days, p =0.007). There were no differences in post-operative Tegner, Lysholm or Kujala scores at final follow-up. Additionally, there were no differences in return to play rates (repair 80.8% vs reconstruction 75.0%, p=0.610) or reoperation rates (repair 20.7% vs reconstruction 13.8%, p=0.487).Conclusions:Repair of the MPFL leads to nearly 3-fold higher rate of recurrent patellar dislocation (41% vs. 14%) at long term follow-up compared to MPFL reconstruction. However, MPFL repair and reconstruction provide similar clinical results, return to play rates and reoperation rates.

Medial Patellofemoral Ligament Repair with Suture Tape Augmentation: A Case Series With Five-Year Follow Up.

The medial patellofemoral ligament (MPFL) is the main restraining force against lateral patellar displacement in the first 20 degrees of knee flexion and is often disrupted following patellar subluxation or dislocation. MPFL reconstruction is commonly performed to restore patellar stability but requires autograft harvest with associated donor site morbidity. The aim of this study was to assess the five-year outcomes of MPFL repair performed with suture tape augmentation. All patients who underwent isolated MPFL repair for recurrent patellar instability between 2011 and 2017 were included. Patients requiring any additional surgery, such as osteotomy, were excluded. Patient-reported outcomes were measured at two-year follow up using the Knee Injury and Osteoarthritis Outcome (KOOS) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Visual Analogue Pain Scale (VAS-pain), Veterans RAND 12-Item Health Survey (VR-12), Marx Activity Scale, and an overall satisfaction questionnaire. At the end of the study period, any complications or secondary surgeries were determined. Eighteen patients underwent MPFL repair with one lost to follow up. There was a significant improvement in all subscales of the KOOS scoring systems, the WOMAC functional score, and the VR-12 physical score. A significant decrease was seen in the VAS-pain score. A non-significant decrease was seen in the Marx activity scale from pre-injury. The majority of patients reported satisfaction with reduction in pain and return to sporting activities. There were no complications with no further instability episodes. This is the first study that describes the five-year follow-up results of patients treated with MPFL repair and suture tape augmentation. Our results show that this technique is an alternative treatment to traditional MPFL reconstruction with comparable outcomes and avoidance of autograft harvest.

Surgical Correction of Non-traumatic Patella Maltracking. Midterm Clinical Follow-up.

BackgroundPatellar instability comprises a group of pathologies that allow the patella to move out of its trajectory within the trochlear groove during walking. Symptomatic patients who need surgery commonly undergo soft tissue procedures such as medial patellofemoral ligament repair to strengthen the ligaments that hold the patella in place. However, soft-tissue repairs may be insufficient in patients suffering from patellar maltracking, which is characterized by an unbalanced gliding of the patella within its route. In these patients, a different approach is advised. We aim to provide the mid-term clinical outcomes of the Fulkerson distal realignment operation in selected patients with non-traumatic patellar maltracking.MethodsThe clinical outcomes of the Fulkerson distal realignment operation performed in 22 knees of 21 patients were evaluated by a self-administered subjective International Knee Documentation Committee (IKDC) score and the Tegner–Lysholm knee scoring scale.ResultsBefore surgery, the median IKDC score was 52, and the median Tegner–Lysholm score was 56. Following surgery (mean follow-up 48 months, range 24–156), the median IKDC and the Tegner–Lysholm scores were 67 and 88, respectively. The improvement was statistically significant (P=0.001 and P=0.002 for IKDC and Tegner–Lysholm scores, respectively). Associated procedures included patella microfracture due to grade III–IV cartilage lesion (International Cartilage Repair Society grading system) in four patients, retinacular releases in three patients, medial capsular augmentations in two patients, and medial patellofemoral ligament reconstruction in two patients. One patient with Ehlers–Danlos disease required excessive medialization of the tibial tuberosity. Surgery-related complications occurred in three patients.DiscussionSurgical correction of patellar maltracking with Fulkerson distal realignment combined with associated procedures in individual patients was associated with an increase in subjective and functional clinical scores at medium-term follow-up. Particular attention should address pathologies associated with patellar maltracking and managed accordingly.Level of evidence4c (case series).

Clinical outcome of Patella stability after fixation of Osteochondral fracture in Acute Primary Traumatic Patella Dislocation without MPFL Repair or Reconstruction

Introduction: Conservative management is advisable for acute primary traumatic patella dislocation (PTPD). Surgical treatment is reserved for osteochondral fractures (OCF), medial patello femoral ligament (MPFL) avulsion/tear, compound injuries, and any underlying bony abnormalities requiring correction. MPFL repair (at avulsed site) or reconstruction along with underlying bony correction in PTPD is controversial. The purpose of this study is to evaluate patella stability after fixation of OCF in PTPD without performing MPFL repair or reconstruction, even in the presence of any underlying bony abnormalities. Material and Methods: This is a retrospective study of eight patients who had PTPD with OCF along with MPFL injury who presented between 2016 and 2019. Pre-operative X-rays and MRI were done to assess the status of MPFL, identify the presence of OCF and to calculate Insall-Salvati index, Tibial Tuberosity-Trochlear groove distance and Trochlear dysplasia. All patients underwent surgery by open approach and OCF fixation by bioabsorbable pins or suture material. MPFL was neither repaired at avulsed site nor reconstructed and even no bony corrections were done. Results: Average size of OCF fragments is 15*7 mm and all involving medial facet of patella. Lysholm score improved significantly from 32.8 to 94.8 and Kujala score from 49.1 to 96 at the end of 6 months. None of the patient had patella instability till latest follow-up, average follow-up period is 4.5 years (3–6 years). Clinically, apprehension test was negative in all cases with full ROM. Post-operative imaging including X-ray and MRI showed complete healing of the OCF along with complete healing/regeneration of MPFL with same pre-existing bony abnormalities if present preoperatively. Conclusion: This study shows excellent patella stability and full knee function along with complete union of OCF and complete healing/regeneration of MPFL in PTPD even in the presence of underlying bony abnormality. Hence, in PTPD with OCF, there is no need to repair/reconstruct MPFL or to correct underlying bony pathology, only OCF fixation is required.

Surgical treatment of acute patellar dislocation associated with bony avulsion in children

Purpose: The management of acute patellar dislocation in children and adolescents is controversial. Traditionally, most first–time traumatic patellar dislocations have been treated nonoperatively. However, due to new knowledge about medial patellar stabilizers some authors have advocated for surgical repair. The present report describes the mid–term subjective and functional results of operative treatment of acute patellar dislocation in children less than eighteen years of age with concomitant osteochondral fracture.&#x0D; Methods: Data on a cohort of sixteen patients (eight girls and eight boys) aged 14.9 years (mean, range 12–17 years) with acute patellar dislocation were retrospectively collected. Intraarticular fragments were detected in all patients in conventional radiographs. Operative treatment consisted of arthroscopic removal (12 cases) or refixation (4 cases) of the osteochondral fragments and direct repair of the damaged medial patellofemoral ligament (MPFL) if that was still feasible (13 cases). All patients were seen at six months, and a telephone interview with twelve patients (75%) was conducted at four years (mean, range 2–7 years).&#x0D; Results: Of the sixteen patients, two (12.5%) had a recurrent patellar luxation. The subjective IKDC score at the time of the most recent follow–up was 86 (mean, range 63–100), and the Marx Activity Rating Scale score was 9.2 (mean, range 2–16).&#x0D; Conclusions: Direct surgical repair of the injured MPFL may be considered an option to prevent subsequent dislocation and subluxation in first–time traumatic dislocation of the patella in children and adolescents with osteochondral fractures and substantial disruption of medial patellar stabilizers.

Medial Patellofemoral Ligament Repair for Recurrent Patellar Instability: Successful Outcomes Among Patients With Low Coronal Malalignment and Normal Patellar Height

Medial patellofemoral ligament (MPFL) repair is discouraged for the treatment of chronic, recurrent patellar instability (RPI) because of high reported failure rates. However, the senior author uses MPFL repair for chronic RPI in the setting of low tibial tubercle-trochlear groove (TT-TG) distance. In this retrospective case series, we report results and evaluate outcome predictors. We used billing records to identify all patients, 14 years or older, who underwent isolated repair for chronic RPI performed by a single surgeon between September 2010 and February 2019. The TT-TG distance, patellar height (Caton-Deschamps Index [CDI]), and trochlear depth were measured on preoperative magnetic resonance imaging; postoperative reports were reviewed; and post hoc Kuala scores were obtained to extend outcome length. Patellar dislocation or revision surgery was considered a failure. Nonfailures were categorized as excellent or fair, based on the most recent report. Univariable generalized estimating equation models were used to evaluate associations of predictors (radiographic parameters, age, ligamentous laxity, primary presenting complaint) with failure and/or success. A total of 93 isolated MPFL repairs were performed. After exclusions were made for workers' compensation insurance (n=4), substance abuse (n=3), major secondary trauma less than 3 months postoperatively (n=3), and follow-up of less than 12 months (n=42), 41 knees (38 patients) had median follow-up of 32 months (interquartile range, 19-48 months). All repairs were patellar sided. Outcomes for 4 knees were considered failures, 23 were excellent, and 14 were fair. Only increased CDI was associated with increased risk of failure (odds ratio, 1.70; 95% CI, 0.98-2.92; P=.06). Mean CDI was 1.23 mm (SD, 0.13 mm) for failures vs 1.08 mm (SD, 0.16 mm) for nonfailures. Failure rate was less than 10% following patellar-sided MPFL repair for treatment of chronic RPI among patients with low TT-TG distance. Increased patellar height was associated with higher risk of failure. [Orthopedics. 2022;45(1):e23-e29.].