Clinical Outcome of Arthroscopic Lateral Retinacular Release for Symptomatic Bipartite Patella in Athletes

Multipartite patella: A review of diagnostic techniques and management of the symptomatic patient

Multipartite patella is an anatomical variant classified by the fragmentation of the main patellar body. The cause of this variant is due to failure in fusion of the patellar ossification centers. It is commonly misdiagnosed as a fracture of the patella in clinical practice, leading to unnecessary treatment measures. The aim of this review is to provide an overview of the development and classification of this variation, diagnostic imaging techniques, and assess the optimal management technique for the symptomatic patient. Multiple radiographic methods are used to identify this variant, with recent studies highlighting high sensitivity rates for nonradiative methods (ultrasound). In terms of symptomatic management, accessory fragment excision and vastus lateralis release provide the greatest alleviation of symptoms, with screw fixation being less favorable.

In-Office Needle Arthroscopy of the Knee With Lateral Parapatellar Retinacular Release

The lateral patellofemoral joint, composed of multiple soft-tissue structures, balances the knee by aiding patella tracking, stability, and force distribution. Arthroscopic lateral release is a well-described procedure that addresses patellofemoral knee pain and, in cases with patellar instability, may be combined with medial stabilization. In-office needle arthroscopy is an up-trending technique that simultaneously diagnoses and treats patellofemoral pathology in the office, leading to a quicker patient recovery, reduced cost, and improved patient satisfaction. The purpose of this Technical Note is to describe in-office needle arthroscopy technique to address patellofemoral pain and lateral patellar mal-tracking, with special consideration for achieving adequate local anesthesia, proper indications, adequate visualization, and the advantages of performing these procedures in the office rather than the operating room.

Trends in Lateral Retinacular Release from 2010 to 2017

Historically, lateral retinacular release (LRR) procedures have been utilized in the treatment of a variety of patellofemoral disorders, including lateral patellar instability. However, in the past decade, there has been an increasing awareness of the importance of the lateral stabilizers in patellar stability, as well as the complications of LRR, such as recurrent medial patellar instability. The purpose of this study was to investigate current trends in LRR procedures from 2010 through 2017 using a large national database. The American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for arthroscopic LRR procedures (the Current Procedural Terminology [CPT] code, 29873) from 2010 to 2017. The number and incidence of lateral release procedures, both isolated and nonisolated, were analyzed and separated into cohorts for analysis. Age and gender of the LRR cohort was investigated and compared with all other orthopaedic procedures during the same time period in the NSQIP database. In addition, concomitant procedures and associated International Classification of Disease-9th Revision (ICD-9) and ICD-10th Revision (ICD-10) codes were analyzed over time and between LRR groups. From 2010 to 2017, 3,117 arthroscopic LRRs were performed. The incidence for LRR was 481.9 per 100,000 orthopaedic surgeries in 2010 and significantly decreased to 186.9 per 100,000 orthopaedic surgeries in 2017 (p < 0.01). LRR was more commonly performed in females (66%) and 58% of patients were under 44 years of age. In addition, LRR was most commonly performed with a concomitant meniscectomy (36%), synovectomy (19%), or microfracture (13%), and for a diagnosis of pain (22%). The overall incidence of LRR procedures significantly decreased from 2010 to 2017. LRRs were more commonly performed in younger, female patients for a diagnosis of pain with the most common concomitant procedure being meniscectomy, synovectomy, or microfracture.

Symptomatic Bipartite Patella in Adults Treated With Open Excision: Outcomes and Management

Introduction

Bipartite patella affects about 2% of people. Most cases are asymptomatic; however, some develop anterior knee pain during a sporting activity or trauma. When conservative treatment fails, surgery can be considered. This study aims to report the outcomes of fragment excision with or without lateral release in adults with the symptomatic bipartite patella.

Methods

The study was approved by the College of Medicine IRB. A retrospective review was performed. Patients were excluded if aged < 18 or had prior knee surgery. Data collected included: age, gender, BMI, sports played, occupation, physical exam findings, Saupe classification, conservative and surgical treatment, advanced imaging used, duration of follow-up, Lysholm score and postoperative complications.

Results

Eight patients were studied. The average age was 28.4 years and BMI was 31.5. Sporting activities included hunting, swimming, soccer, golfing and softball. Occupations included office job, laborer, manufacturing plant worker and truck driver. All patients complained of anterior knee pain exacerbated by sports or work. All patients failed >6 months of conservative treatment. Saupe classification included seven types III (superolateral) and one type II (lateral). Surgical treatment included one open excision, six arthroscopic-assisted open excisions and one arthroscopic-assisted open excision with the lateral release. The duration of follow-up averaged 15 months. The average preoperative and postoperative Lysholm score was 75 and 93, respectively. One postoperative complication occurred.

Conclusions

Bipartite patella is an uncommon cause of anterior knee pain in adults. When pain persists despite conservative care, fragment excision of less than 12% of the whole patella with or without lateral release resulted in excellent outcomes in the majority of cases.

Outcomes of surgical treatment of symptomatic bipartite patella in teenage athletes

Bipartite patella affects about 2% of people. Most cases are asymptomatic; however, some develop anterior knee pain during sports. When conservative treatment fails, surgery can be considered. This study reports the outcomes of fragment excision with or without lateral release in teenage athletes with symptomatic bipartite patella. The study was approved by the College of Medicine Institutional Review Board. A retrospective review was performed. Patients were excluded if age >18 or had prior knee surgery. Data collected included age, gender, BMI, sports played, Saupe classification, conservative and surgical treatment, advanced imaging used, duration of follow-up, Lysholm Score and postoperative complications. Five teenage patients were studied. The average age was 15.6 years and BMI was 23. Sports played included basketball, football, track-and-field and soccer. All patients complained of anterior knee pain exacerbated by sports. All patients failed >6 months of conservative treatment. Saupe classification included four type III (superolateral) and one type II (lateral). Two patients had an MRI. Surgical treatment included two open excisions and three arthroscopic-assisted open excisions with lateral releases. The average Lysholm Score was 97. Postoperatively, all patients returned to presurgery sporting activity at an average of 9.8 weeks (range, 6-13 weeks). A 16-year-old male treated by open excision developed a postoperative wound infection. He was successfully treated with irrigation & debridement and antibiotics and returned to sports at 6 weeks. Symptomatic bipartite patella is an uncommon cause of anterior knee pain in adolescent athletes. When pain persists despite conservative care, fragment excision with or without lateral release resulted in excellent pain relief and return to full sporting activity in all cases.

Treatment of congenital bipartite patella in pediatric population - a systematic review of the published studies

Bipartite patella is an abnormality where patella is incorrectly ossified resulting in fibrocartilaginous synchondrosis. In most cases bipartite patella is asymptomatic and incidental finding but can also be painful especially in adolescents. The aim of our analysis was to determine the preferable treatment for pediatric bipartite patella. We conducted a systematic review based on PubMed and Embase searches. All original articles with reference to treatment in the population of ≤ 20 years of age, were included. Case reports, and articles without individualized data were excluded. In total, the individual data of 126 knees in 116 patients was analyzed. In 77.8% (98/126) of the analyzed knees the result was excellent, and the majority of the knees, 89.7% (105/126) received surgical intervention, and seven different techniques were used. None of operative methods were superior to others. Excellent treatment outcomes were achieved more often in younger patients (p=0.004), and the median duration of symptoms in operatively treated patients was shorter (p=0.018). If operative treatment is used after unsuccessful conservative treatment, it should be considered early in adolescence and also within a relatively short period after the onset of symptoms. The best operative method could not be found. More research and RCTs are needed concerning the conservative methods and different operative techniques.

Alignment changes after open-wedge high tibial osteotomy result in offloading in the patellofemoral joint: a SPECT/CT analysis

PURPOSE

The patellofemoral (PF) joint may be adversely affected by medial open-wedge high tibial osteotomy (OWHTO). This study aimed to evaluate the PF compartmental changes using combined single-photon emission computed tomography (SPECT) and conventional computed tomography (CT) after OWHTO to provide clinical guidance regarding the PF joint pressure and force.

METHODS

Patients with medial osteoarthritis and varus malalignment > 5° were treated using OWHTO. Patients with a minimum 2-year follow-up were included in the study. The patellar positions were evaluated based on the radiographic parameters. The changes in chondral lesions during second-look arthroscopic examination were evaluated, and the PF joint arthritis grade was recorded on patellar Merchant radiographs using Kellgren-Lawrence classification. The PF compartmental changes according to SPECT/CT analysis after OWHTO were evaluated in all patients. The scintigraphic uptake was graded on four scales. Patients were divided into improved and unimproved groups according to the PF compartmental grade using the SPECT/CT uptake grading system.

RESULTS

At a mean follow-up period of 47.0 months (range 25-74 months), the mean mechanical femorotibial angle changed significantly from varus 6.3° (range 5-12°) to valgus 2.6° (range 0-8°); p < 0.001) postoperatively. The radiological parameters presenting patellar positions, including the tibial slope, patellar convergence angle, and lateral tilt angle, did not change significantly between the preoperative values and the 2-year follow-up values. The mean patellar height significantly decreased (0.07 ± 0.14, p = 0.001 according to the Blackburn-Peel index and 0.32 ± 0.23, p < 0.001 using the modified Insall-Salvati ratio). The average tibial tubercle to trochlear groove (TT-TG) distance significantly decreased from 14.1 to 12.2 mm (p < 0.001). The Q angle also significantly decreased from 9.8^o to 7.7^o (p = 0.008). Chondral lesions of the patella and trochlear groove revealed significant deterioration; at 2 years after OWHTO, the arthritic grades of the PF joints worsened significantly, as determined by radiography (p = 0.007). Scintigraphic uptake in the PF joint was significantly lower (from 2 to 1) at 2 years postoperatively compared to that immediately after the index operation (p < 0.001). Only 4 of 56 (7.1%) patients showed increased uptake. Comparison between the improved and unimproved groups according to scintigraphic uptake changes revealed that the changes in the cartilage status on the patellar undersurface and TT-TG distance were the most significant predictive factors of increased scintigraphic uptake in the PF joint after OWHTO.

CONCLUSION

Alignment correction by OWHTO result in PF compartment offloading and should be considered when identifying the surgical indications for OWHTO.

LEVEL OF EVIDENCE

Therapeutic, Level IV.

Arthroscopic Management for Bipartite Patella: A Systematic Review

Background:

Bipartite patella is a rare congenital condition that becomes painful following direct trauma or an overuse injury. If it remains painful despite nonoperative treatment, surgery may be warranted. The current gold standard is open fragment excision or lateral release; however, arthroscopic management is also possible.

Purpose:

To investigate the safety and efficacy of arthroscopic treatment of painful bipartite patella.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

Using Medline and Embase, we systematically reviewed the literature as of March 8, 2020, using the subject headings “bipartite patella” and “arthroscopy” and related key terms. All levels of evidence involving human studies in English were included. Articles were excluded if only the abstract was published or the study was related to nonsurgical treatment or nonrelated diagnoses. Data related to journal/article information, demographic/clinical data, arthroscopic technique, length of follow-up, treatment outcomes, and complications were extracted.

Results:

Eleven articles with 43 patients were included in the review. Most patients (n = 34; 79%) underwent arthroscopic lateral release, while 16% (n = 7) had arthroscopic excision of the accessory fragment and 5% (n = 2) had arthroscopic excision and release. All patients except for one, who experienced postoperative trauma, were pain-free after arthroscopic treatment and were able to return to sports after a mean 2.6 months.

Conclusion:

This review demonstrated that arthroscopic management of painful bipartite patella is a safe and effective alternative to open surgical excision or release. However, all articles were case studies or small case series, owing to the rarity of the condition. In the future, higher-level studies comparing arthroscopic techniques and postoperative rehabilitation programs should be performed.

Isolated Arthroscopic Lateral Retinacular Release for Lateral Patellar Compression Syndrome

Introduction: Evidence concerning the role of isolated lateral retinacular release (LRR) for lateral patellar compression syndrome (LPCS) dates back at least three decades. Appropriate indications, execution and outcomes still remain unclear and controversial. The present investigation analyzed the midterm result of isolated and arthroscopic LRR for LPCS in a cohort of patients who underwent such procedure at our institution. Material and methods: Patients undergoing isolated arthroscopic LRR for LPCS were identified retrospectively from our electronic database. All procedures were performed by two experienced surgeons. Patients with bony and/or soft tissues abnormalities, patellofemoral instability, moderate to severe chondral damage were not included. Patients with previous surgeries were not included, as were those who underwent combined interventions. Clinical scores and complications were recorded. Results: 31 patients were recruited in the present investigation. The mean follow-up was 86.0 ± 22.8 months. The mean age of the patients at the index operation was 34.2 ± 13.1 years. A total 55% (17 of 31) were women, and 58% (18 of 31) had involved the right knee. The mean hospitalization length was 3.5 ± 1.4 days. At a mean follow-up of 86.0 ± 22.8 months, the numeric rating scale (NRS) was 1.2 ± 0.8, the Kujala score was 91.3 ± 11.3, the Lysholm score was 93.1 ± 15.0, and the Tegner score was 5.0 ± 1.8. At the latest follow-up, 9 of 31 (29.0%) of patients experienced compilations. One patient (3.2%) had a post-operative hemarthrosis which was managed conservatively. Six patients (19.4%) reported a persistent sensation of instability, without signs of patellar dislocation or subluxation. One patient underwent an arthroscopic meniscectomy, and another patient an anterior cruciate ligament (ACL) reconstruction. Conclusion: isolated arthroscopic lateral retinacular release for lateral patellar compression syndrome is feasible and effective, achieving satisfying results at more than seven years following the procedure.

Outcome and experience of arthroscopic lateral retinacular release combined with lateral patelloplasty in the management of excessive lateral pressure syndrome

Background

Only a few studies have described the effect of full arthroscopic surgery in treatment of excessive lateral pressure syndrome (ELPS). Therefore, the purpose of this study was to assess the clinical efficacy and experience of total arthroscopic lateral retinacular (LR) release and lateral patelloplasty for the treatment of ELPS.

Methods

A total of 73 patients (88 knees) with ELPS underwent arthroscopic LR release and lateral patelloplasty. The visual analogue scale (VAS), Kujala score, Lysholm scores, patella medial pushing distance, patellar tilt angle (PTA), and lateral patellofemoral angle (LPFA) were measured and evaluated before and after surgery.

Results

Follow-up ranged from 12 to 36 months with an average of 24 ± 5.8 months. The VAS was significantly lower at the last follow-up than before surgery (P < 0.01). The patella medial pushing distance, Kujala score, Lysholm score, PTA, and LPFA were significantly higher at the last follow-up than before surgery (P < 0.01, respectively). Years and lateral patella Outerbridge classification at the last follow-up have negative correlation with Kujala score, Lysholm score, Patella medial pushing distance, PTA, and LPFA (P < 0.01, respectively) and have positive correlation with VAS (P < 0.01, respectively). Related complications were not reported.

Conclusions

Full arthroscopic LR release combined with lateral patelloplasty in the treatment of ELPS is an effective minimally invasive method, which can effectively correct anomalies of force line and skeleton of patella, relieve pain, and restore knee joint motor function with less complications.

Operative Treatment of Bipartite Patella in Pediatric and Adolescent Athletes: A Retrospective Comparison With a Nonoperatively Treated Cohort

Background:

Bipartite patella (BPP) is a developmental anomaly that forms when incomplete patellar ossification leaves a residual fibrocartilaginous synchondrosis between ossification centers. Repetitive traction forces across the synchondrosis can cause knee pain, most commonly presenting in adolescence. Symptoms frequently resolve with nonoperative management. Few surgical case series exist to guide treatment approaches for refractory pain.

Purpose:

To investigate the clinical features, surgical techniques, and outcomes associated with operative treatment of symptomatic BPP in pediatric and adolescent athletes and to compare features of the series with a large control group managed nonoperatively.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective medical record review was conducted of all patients aged ≤20 years who were diagnosed with symptomatic, radiologically confirmed BPP between 2003 and 2018 at a single tertiary-care pediatric hospital (N = 266). Demographic and clinical variables were analyzed, and additional radiologic and perioperative variables were collected for the surgical subcohort.

Results:

Of the 266 patients included, 27 were treated operatively (10.2%). When compared with those treated nonoperatively (with rest, physical therapy, cryotherapy, and anti-inflammatory medications), the operatively managed group experienced a longer duration of symptoms before first presentation (21.5 vs 7.6 months; P < .001) and were more likely to be older (mean age, 15.4 vs 12.4 years; P < .001), female (59.3% vs 35.6%; P = .03), and competitive athletes (100% vs 84.5%; P = .02). In the 27 patients treated operatively, procedures were categorized as isolated fragment excision (n = 9), fragment excision with lateral release (n = 8), isolated lateral release (n = 5), fragment screw fixation (n = 4), and synchondrosis drilling (n = 1). The mean time between surgery and return to sports was 2.2 months. Four patients (14.8%) reported residual symptoms requiring secondary surgery, including lateral release (n = 1), excision of residual fragment (n = 1), and fixation screw removal (n = 2).

Conclusion:

BPP can cause knee pain in adolescent athletes and is generally responsive to nonoperative treatment. Patients undergoing surgical treatment—most commonly female competitive athletes with prolonged symptoms—represented 10% of cases. A variety of surgical techniques may be effective, with a 15% risk of persistent or recurrent symptoms warranting reoperation. Prospective multicenter investigations are needed to identify optimal candidates for earlier interventions and the optimal operative treatment technique.

Arthroscopic Lateral Retinacular Release and Modified Goldthwait Technique for Patellar Instability

Surgical options for patellofemoral (PF) disorders include proximal or distal realignment, cartilage restoration techniques, open or arthroscopic lateral retinacular release, and medial soft-tissue reefing. Skeletal immaturity and donor-site morbidity can be of concern in most reconstructive procedures. The Goldthwait procedure with hemi-patellar transfer and medialization combined with arthroscopic lateral retinacular release results in medialization of the PF contact point in flexion and corrects maltracking to prevent recurrent patellar dislocation. This functional procedure is indicated for PF instability and has historically been used in children to accommodate the immaturity of the tibial tubercle and physis. The purpose of surgical correction is to improve PF tracking, reducing the lateralizing forces on the patella with the correction of the Q angle (angle between the quadriceps tendon and patellar tendon). The purpose of this Technical Note was to describe, in detail, arthroscopic lateral retinacular release combined with the modified Goldthwait procedure for recurrent patellar instability.

Goldthwait technique for patellar instability: surgery of the past or here to stay procedure? A systematic review of the literature

Patellar instability is the pathologic condition where the patella is prone to recurrent lateral dislocation. The clinical results on large series of patients and long-term outcome of Goldthwait techniques have not been described in the literature. The aim of this systematic review is: (1) to analyze and summarize the available literature focused on Goldthwait procedure in the treatment of recurrent patellar dislocation and (2) to evaluate the clinical and functional outcomes of patients treated with this surgical procedure. A systematic review of the literature was performed to investigate the results of Goldthwait procedure according to the PRISMA 2009 guidelines. A total of 7 articles published were systematically reviewed. A total of 197 knees (182 patients: 86 males and 96 females) have been treated with Goldthwait procedure. The mean reported follow-up was 6.8 years. The mean age at surgery was 18 years old. The Goldthwait procedure was associated with open lateral retinacular release in 127 (64.5%) knees to arthroscopic lateral retinacular release in 20 (10.1%) knees, and with retinacular plasty and a vastus medialis advancement in 33 (16.7%) knees. Only in 17 (8.6%) knees the Goldthwait procedure was performed as an isolated procedure. Poor standardization of methodological assessment has been observed. Despite the limitations of the available literature, the Goldthwait technique provides satisfying results for the treatment of patellar instability even in pediatric population. More high-quality studies are necessary to evaluate the long-term complications and the real incidence of long-term PF osteoarthritis.

Ultrasound-guided injection and the pie crust technique for the treatment of symptomatic bipartite patella

PURPOSE

This study aimed to investigate the results of a new treatment procedure (ultrasound-guided injection and the "pie crust" technique for lengthening of capsular tendon structures) for symptomatic bipartite patella.

METHODS

We retrospectively investigated patient outcomes following the treatment of symptomatic type III bipartite patella with our new technique. Fifteen knees in 14 boys (mean age, 13.0 ± 1.7 years) were included. The procedure involved the injection of 1% lidocaine (2 mL) and triamcinolone acetonide (5 mg) between the patella and fragment. We then punctured 10 sites from one skin puncture to extend lateral capsular tendon structures. The patients were clinically assessed using the Victorian Institute of Sports Assessment (VISA) score before and 1 week, 1 month, and 3 months after the procedure. Patients were also evaluated for complications.

RESULTS

The average VISA score was 45.7 ± 4.7 before treatment, 70.6 ± 7.3 at 1 week post-treatment, 84.4 ± 16.6 at 1 month post-treatment, and 88.6 ± 18.3 at 3 months post-treatment. The VISA score improvement from before the procedure to 1 week after the procedure was significant (P < 0.01). There were no complications in any of the patients, who returned to sports at a mean of 4.2 ± 2.1 weeks after the procedure. However, two patients (three knees) had poor results and could not return to action; thus, they underwent surgical treatment 4 months after the ultrasonographic procedure.

CONCLUSIONS

This novel method is a potential treatment option for the management of symptomatic bipartite patella in outpatient clinics.

Predictive Factors for Patellofemoral Degenerative Progression After Opening-Wedge High Tibial Osteotomy

PURPOSE

To identify risk factors for patellofemoral degenerative progression after opening-wedge high tibial osteotomy (HTO) and to investigate the effect of patellofemoral degeneration on the patellofemoral specific patient-reported outcomes.

METHODS

Between March 2010 and June 2016, 94 knees (86 patients) underwent hardware removal with second-look arthroscopy at 21.4 months after opening-wedge HTO with first-look arthroscopy (mean follow-up duration, 49.8 months). Predictive factors for patellofemoral degeneration, including demographics, preoperative and postoperative mechanical axis (MA) of the lower limb (positive and negative MA indicating varus and valgus, respectively), tibial slope, and modified Blackburne-Peel ratio, were evaluated. Patients were divided into the progression and nonprogression groups according to their patellofemoral degenerative progression from first to second arthroscopy. Clinical outcomes, including the Kujala score and Knee Injury and Osteoarthritis Outcome Score, and radiographic outcomes were compared between the 2 groups.

RESULTS

Postoperative MA (adjusted odd ratio, 0.62; P < .001) was the most significant predictive factor for progressive change in the patellofemoral joint (R_n² = 0.31). Twenty-eight knees (30%) showed patellofemoral degenerative progression. Mean postoperative Kujala score (progression group 60.5 vs nonprogression group, 72.3; P = .005) and Knee Injury and Osteoarthritis Outcome Score scales (except for the symptom subscale) were lower in the progression group. Postoperative MA was significantly more corrected in the progression group (progression group -5.1° ± 2.7° vs nonprogression group -2.4° ± 2.3°; P < .001).

CONCLUSIONS

Postoperative MA, which might be related to overcorrection, is correlated with patellofemoral degenerative progression after opening-wedge HTO. Patients with patellofemoral degenerative progression showed inferior patient-reported outcomes.

LEVEL OF EVIDENCE

Level IV, case series with subgroup analysis.

Editorial Commentary: Got Evidence? What We Really Need Is an Algorithm for Treating Symptomatic Bipartite Patella

Bipartite patella is an uncommon but potentially troublesome problem for young athletes. Numerous uncontrolled retrospective studies have reported good results after various treatments. What is needed are studies that will guide workup and support treatment decisions based on the condition of the cartilage surfaces of the fragment, presence of pseudoarthrosis, and size and location of the fragment. To support decisions, we need prospective comparative studies, either randomized or, at least, prospective cohort studies that identify patients at the time of presentation, document key decision points, and follow patients to successful resolution of symptoms.