Patellar Dislocation In Adolescents Research Articles

Consensus-Based Guidelines for Management of First-Time Patellar Dislocation in Adolescents.

The management of first-time patellar dislocation remains variable, with limited evidence to support or compare different operative and nonoperative modalities. The primary aim was to establish consensus-based guidelines for different components of nonoperative treatment following a first-time patellar dislocation. The secondary aim was to develop guidelines related to management after failed nonoperative treatment. The tertiary aim was to establish consensus-based guidelines for the management of first-time patellar dislocation with a concomitant osteochondral fracture. A 29-question, multiple-choice, case-based survey was developed by 20 members of the Patellofemoral Research Interest Group of the Pediatric Research in Sports Medicine Society. The survey consisted of questions related to demographic information, management of first-time patellar dislocation without an osteochondral fracture, and management of first-time patellar dislocation with a 2cm osteochondral fracture. The survey underwent 2 rounds of iterations by Patellofemoral Research Interest Group members and the final survey was administered to Pediatric Research in Sports Medicine members, using REDCap. Consensus-based guidelines were generated when more than 66% of respondents chose the same answer. Seventy-nine of 157 (50%) eligible members responded. Sixty-one were orthopaedic surgeons and 18 were primary sports medicine physicians. Eleven consensus-based guidelines were generated based on survey responses. Those that met the criteria for consensus included initial knee radiographs (99% consensus), nonoperative treatment for first-time patellar dislocation without an osteochondral fracture (99%), physical therapy starting within the first month postinjury (99%), with return to sport after 2 to 4 months (68%) with a brace (75%) and further follow-up as needed (75%). Surgical treatment was recommended if there were patellar subluxation episodes after 6 months of nonoperative treatment (84%). Patellar stabilization should be considered for a first-time dislocation with an osteochondral fracture (81.5%). Consensus-based guidelines offer recommendations for the management of first-time patellar dislocation with or without an osteochondral fracture. Several changing trends and areas of disagreement were noted in clinical practice. In the absence of high-level evidence, consensus-based guidelines may aid in clinical decision-making when treating patients following a first-time patellar dislocation. These guidelines highlight the evolving trends in clinical practice for the management of first-time patellar dislocation. Areas not reaching consensus serve as topics for future research.

Clinical significance of polymorphisms of genes encoding collagen (COL1A1, COL5A1) and their correlation with joint laxity and recurrent patellar dislocation in adolescents

The aim of this study was to assess the coexistence of polymorphisms of the COL1A1 and COL5A1 genes with clinically diagnosed laxity and the occurrence of recurrent patellar dislocation in adolescents. The research group comprised 50 cases of recurrent patellar dislocation. The mean age at diagnosis was 14.2 years (10–17, SD 2.6). The control group consisted of 199 participants without a diagnosis of recurrent patellar dislocation, with a mean age of 15.2 (10–17 years, SD 2.7). Joint laxity by the Beighton scale was assessed. Analysis of the allele distribution of the analysed genes COL1A1 and COL5A1 revealed no statistically significant difference between the study group and the control group (p = 0.859 and p = 0.205, respectively). Analysis of the Beighton score showed a statistically significantly higher result in the study group than in the control group (p < 0.001). No correlation between the presence of polymorphisms and joint laxity diagnosis was confirmed. In conclusion, COL1A1 and COL5A1 gene polymorphisms are not significantly more common in adolescents with recurrent patellar dislocation than in healthy peers; there is also no correlation between joint laxity and polymorphisms of the COL1A1 and COL5A1 genes.Registered on ClinicalTrials.gov with ID: PMMHRI-2021.2/1/7-GW.

A Combined Surgical Approach for Recurrent Patellar Dislocation in Adolescents With Patella Alta and Increased Tibial Tuberosity-Trochlear Groove Distance: Improved Clinical Outcomes but Decreased Posterior Tibial Slopes in Skeletally Immature Patients at Minimum 4-Year Follow-Up

Purpose(1) To report the clinical and radiological outcomes of a surgical technique combining anatomic medial patellofemoral ligament (MPFL) reconstruction and tibia tuberosity transfer in adolescents with patella alta and elevated tibial tuberosity-trochlear groove (TT-TG) distance, in the treatment of recurrent patellar dislocation (RPD); (2) To investigate the potential risks of growth arrest or developmental deformities associated with this combined technique. MethodsMedical records of patients underwent the combined surgery were reviewed from 2015 to 2019. This study included adolescents aged between 14 and 18 years with a Caton-Deschamps index (CDI) greater than 1.30 and TT-TG distance greater than 20mm, with a minimum follow-up of 4 years. Radiological examinations including lateral views and full-length posteroanterior standing radiographs were investigated to assess patella height by CDI, posterior tibia slope (PTS) angle, side-to-side difference (SSD) in bone length, and lower extremity alignment by hip-knee-ankle (HKA) angle; CT-scans and MRI profiles were investigated to evaluate TT-TG distance and staging of growth plate closure. Other evaluations included preoperative and postoperative physical examination, Kujala score, and Tegner activity score. The patients were stratified into 3 subgroups according to a MRI-based staging system of the growth plate closure, and each outcomes were analyzed. A cohort-specific minimal clinically important difference (MCID) estimation was performed using standard error of measurement. ResultsThe average age at the time of surgery was 16.1 years (range, 14.1-17.8). The average follow-up was 5.6 years (range, 4.0-7.6). No recurrent dislocation occurred, no clinically significant deformity or axis deviation was encountered. Postoperative patellar height by CDI was 1.00±0.11 (range, 0.81-1.15). No significant differences were found in pre- and postoperative HKA angle and SSD in femur/tibia length among all subgroups. A significantly decreased PTS angle was found in patients with open growth plates, from 10.2±1.7° preoperatively to 8.1±1.0° postoperatively (P=.015). The Kujala score and Tegner score both significantly improved, from 65.5±13.9 preoperatively to 90.4±7.2 postoperatively in Kujala score (P <0.001), and from 4.0±1.1 preoperatively to 4.7±1.3 postoperatively in Tegner score (P <0.001). Of the whole cohort, 63.1%, 100%, 47.1% and 94.1% patients achieved the MCID for PTS angle, CDI, Tegner score, and Kujala score respectively. ConclusionThis combined technique is safe and effective in treating RPD in skeletally mature adolescents with concurrent patella alta (CDI > 1.30) and TT-TG distance > 20mm, permitting patients to have improved knee function and low complication rates. Nonetheless, patients with open growth plates demonstrated a decrease in PTS, which might predispose the knee to recurvatum and osteoarthritis in the long-term. Study DesignRetrospective therapeutic case series; level of evidence, Ⅳ.

Poster 241: Outcomes of Trochleoplasty for Recurrent Patellar Dislocation in Adolescents with Open Physes

Objectives: Patellofemoral dislocation, the most severe presentation on the spectrum of patellar instability, is most common in adolescent populations. Trochlear dysplasia is an integral component of the disorder, and procedures aimed at correcting instability by addressing this dysplasia are often necessary. A theoretical risk of injury to the distal femoral physis exists in these surgeries. At our institution, a thick-flap sulcus deepening technique is used to re-shape the trochlear groove. The risk of injury to the physis in this procedure is not clearly delineated in the current literature. We investigated the outcomes in adolescent patients undergoing this procedure, hypothesizing that patients with open distal femoral physes and less than 2 years of remaining growth can safely and successfully undergo thick-flap sulcus deepening trochleoplasty. Methods: Seventeen adolescents (21 knees) with open physes underwent thick-flap trochleoplasty at our institution. Preoperative radiographs were used to evaluate leg axis and patella alta. Preoperative MRI was used to determine trochlear dysplasia (sulcus depth, spur height, patellofemoral index) and tibial tuberosity to trochlear groove distance (TTTG) distance. Preoperative and postoperative AP and lateral radiographs were used to evaluate and compare the lateral distal femoral angle (LDFA) and Blumensaat’s angle (BA). Preoperative and postoperative IKDC and Kujala outcome scores were measured to evaluate clinical improvement. Results: Median age at time of operation was 14.9 years for girls and 15.5 for boys. Mean follow up was 5.4 years from surgery. At two-year follow up, growth plates were closed in all but one knee. No clinical differences to the leg length or alignment were appreciated. There was no statistically significant change in lateral distal femoral angle (mean change 0.74 degrees, p = 0.1074). There was a statistically significant change in Blumensaat’s angle (mean change 0.89 degrees, p = 0.0477). Mean Kujala score improved significantly from 60.19 preoperatively to 90.36 postoperatively, p= 0.0008. Mean IKDC score improved significantly from 59.37 preoperatively to 87.21 postoperatively, p = 0.00064. There was recurrent instability in one knee, requiring revision surgery with distal femur and Fulkerson osteotomies. Conclusions: Adolescent patients nearing skeletal maturity can safely and successfully undergo thick- flap sulcus deepening trochleoplasty for patellar instability resulting from trochlear dysplasia. At follow- up, there was no clinical evidence of growth disturbances, and postoperative imaging demonstrated less than 1 degree difference in LDFA and BA at skeletal maturity, which are unlikely to be of clinical significance. These findings should be interpreted very carefully, as specific patient selection, trochleoplasty expertise, and extreme caution are still necessary to prevent iatrogenic injury to the distal femoral physis.

A preliminary study of proximal realignment combination surgery in the treatment of adolescent habitual patellar dislocation

ObjectiveA combination of lateral soft tissue release, medial soft tissue contraction, vastus medialis anterior placement, medial patellofemoral ligament reconstruction, and rectus femoris insertion reconstruction are introduced in the treatment of habitual patellar dislocation in adolescents.MethodsA retrospective analysis was performed on 12 patients (17 knees) with habitual patellar dislocation and unclosed epiphyses who underwent surgical treatment at the First Hospital of Jilin University from May 2017 to November 2021. The Lysholm scores and Q angle were collected preoperatively and at final follow-up and were compared.ResultsTwelve patients (4 boys and 8 girls) aged 10–15 years were retrospectively analysed, who followed up for an average of 21 months (5–48 months). The range of motion of the knee joint returned to normal in all patients, and no cases of complications including surgical site infection, joint stiffness, or patellar re-dislocation occurred. The mean Lysholm scores and Q angles improved from 73.9, and 19.6° preoperatively to 91.7, and 13.9° at the final follow-up, respectively.ConclusionThe preliminary effect of the combination surgery for habitual patellar dislocation in adolescents was satisfactory.

Retracted: Anatomic Risk Factors for Osteochondral Fracture of Acute First-Time Patellar Dislocation in Adolescents: A Retrospective Magnetic Resonance Imaging Study.

[This retracts the article DOI: 10.1155/2022/6723326.].

Anatomic Risk Factors for Osteochondral Fracture of Acute First-Time Patellar Dislocation in Adolescents: A Retrospective Magnetic Resonance Imaging Study.

Objective To analyze the risk factors for osteochondral fracture (OCF) of first-time acute patellar dislocation (APD) through measurements of patellofemoral anatomy in adolescents. Methods In this prospective study, all patients were divided into two groups according to whether OCF was detected on magnetic resonance imaging (MRI): Group A (associated with OCF) and Group B (without OCF). Patellofemoral anatomy was evaluated with four aspects including trochlear/patellar dysplasia, patella location, patellofemoral matching, and morphologic classification. On MRI scans, trochlear facet asymmetry ratio (TFAR), lateral trochlear inclination (LTI), sulcus angle (SA), trochlear depth (TD), and patellar depth (PD) were measured to assess trochlear/patellar dysplasia. Insall–Salvati index (ISI), Caton–Deschamps index (CDI), Blackburne–Peel index (BPI), lateral patellofemoral angle (LPFA), patellar tilt angle (PTA), and lateral patellar displacement (LPD) were measured to show the location of patella. Patellofemoral matching was analyzed through the measurements of patellofemoral congruence angle (PFCA), patellofemoral index (PFI), and patellotrochlear index (PTI). Results A total of ninety-four adolescents from 49 boys and 45 girls (mean age, 15 years; range, 10–18 years) with first-time APD were recruited and included in Group A (65) and Group B (29). The PFI (2.62 ± 0.51 vs. 2.10 ± 0.44) and PTI (0.28 ± 0.05 vs. 0.22 ± 0.07) were significantly higher in Group B than Group A (P < 0.05). There were no significant differences in other quantitative outcomes of the two groups (P > 0.05). The distribution of Dejour/Wiberg classification was statistically similar between the two groups (P > 0.05). Conclusions Adolescent patients with first-time APD complicating OCF have closer morphologic features of patellofemoral dysplasia and patella location when compared to adolescents without OCF. Abnormal patellofemoral matching increases the risk of OCF after first-time APD in adolescents.

Osteochondral Fractures in Acute Patellar Dislocations in Adolescents: Midterm Results of Surgical Treatment.

Background:Osteochondral fractures (OCFs) are common injuries during acute patellar dislocation (APD), carrying a high risk of early joint deterioration if left untreated. The recommended approach is reduction and stable fixation; however, data on the results of such treatment are limited.Purpose:To evaluate midterm results of fixation of APD-related OCFs in adolescents and to identify predictive factors for poor outcomes.Study Design:Case series; Level of evidence, 4.Methods:This was a retrospective analysis of adolescent patients who underwent internal fixation of APD-related OCFs between 2004 and 2015 at a single tertiary pediatric trauma center. The primary outcome variables included Knee injury and Osteoarthritis Outcome Score (KOOS), patient satisfaction (0-10 scale), and sports participation compared with preoperative level. Secondary outcome variables included relationship between final results and OCF location (patellofemoral vs tibiofemoral), surgical delay (>6 weeks), and patellar instability after OCF fixation. OCF healing was evaluated using magnetic resonance imaging (MRI).Results:Included were 40 patients (19 female, 21 male) with 42 OCFs (29 patellar OCFs, 13 lateral femoral condyle OCFs). The median patient age at surgery was 14.5 years (interquartile range [IQR], 13-15.5 years), and median follow-up was 76 months (IQR, 52.5-95 months). Recurrence of patellar instability occurred in 27.5% of patients. Median overall KOOS was 93.8 (IQR, 90.8-97.6); KOOS–Symptoms, 92.9 (IQR, 85.7-96.4); KOOS–Pain, 97.2 (IQR, 91.7-100); KOOS–Activities of Daily Living, 100 (IQR, 97.1-100); KOOS–Sports, 90 (IQR, 80-100); and KOOS–Quality of Life, 78.1 (IQR, 56.2-87.5). Median satisfaction score was 8 (IQR, 8-9), and 16 patients (40%) returned to sports participation at their preinjury level. MRI scans revealed a 100% rate of bone healing. Abnormalities exceeding the fracture area were evident on MRI scans in 86.5% of patients. Recurrence of patellar instability (even after surgical fixation) and unstable patella at final follow-up were independent predictors of worse results after OCF fixation.Conclusion:In the current study, reduction and internal fixation for APD-related OCF in adolescents yielded favorable midterm outcomes. Recurrence of dislocation and persistent patellar instability jeopardized clinical results.

MANAGEMENT OF FIRST-TIME PATELLAR DISLOCATION: A SURVEY OF PRISM MEMBERS (201)

Objectives:There are no current guidelines for optimal management of first-time patellar dislocation in children and adolescents. The objective of this study was to develop consensus-based guidelines for management of first-time dislocation in adolescents.Methods:A 29-question, case-based, multiple-choice survey was developed after 2-rounds of iterations by 20 members of the Patellofemoral RIG. The survey contained two case scenarios of first-time patellar dislocation in adolescents - one with and one without an osteochondral fracture. The survey was administered to primary sports medicine and orthopedic surgeons of the PRISM Society in April 2020 and the responses were analyzed. Consensus-based guidelines were generated when at least 66% of the respondents agreed.Results:81/276 (29%) members responded to the survey and 6 consensus-based guidelines were generated from those responses (Table 1).There was no consensus between conservative (60%) and operative (40%) treatment of contralateral patellar dislocation. Free-text analysis revealed several variables that influence the decision-making process.Conclusions:There are changes in trends related to management of first-time dislocation in adolescents. MRI, though not recommended for all patients with first-time dislocation, was obtained by 51% of respondents. The survey provides details of conservative treatment, including the role and duration of bracing and physical therapy. For first-time dislocation with an osteochondral fracture, concomitant patellar stabilization is preferred over isolated fixation. Simultaneous guided-growth for genu valgum correction is recommended. There were several variables that influenced the decision-making process and there were several areas of discordance. Further research studies on these parameters could potentially improve outcomes. *PF RIG members: Matthew Ellington, MD, Craig J Finlayson, MD, Joseph Molony, Jr., PT, MS, SCS, CSCS, Nicole Friel, MD MS, Daniel W Green, MD, Jeffery L Mikutis, DO, Todd A Milbrandt, MD, James L Pace, MD, Albert M Pendleton, MD, Lauren H Redler, MD, Jason Rhodes, MD, Shannon D Safier, MD, John A Schlechter, MD, Beth E Shubin Stein, MD, Curtis Vandenberg, MD, Jeffrey M Vaughn, DO, Eric J Wall, MD, Drew E Warnick, MD, Moshe Yaniv, MD, Shital N Parikh, MD.

MANAGEMENT OF FIRST-TIME PATELLAR DISLOCATION: A SURVEY OF PRISM MEMBERS

Background:There are no current guidelines for optimal management of first-time patellar dislocation in children and adolescents.Purpose:To develop consensus-based guidelines for management of first-time dislocation in adolescents.Methods:A 29-question, case-based, multiple-choice survey was developed after 2-rounds of iterations by 20 members of the Patellofemoral RIG. The survey contained two case scenarios of first-time patellar dislocation in adolescents - one with and one without an osteochondral fracture. The survey was administered to primary sports medicine and orthopedic surgeons of the PRISM Society in April 2020 and the responses were analyzed. Consensus-based guidelines were generated when at least 66% of the respondents agreedResults:81/276 (29%) members responded to the survey and 6 consensus-based guidelines were generated from those responses.There was no consensus between conservative (60%) and operative (40%) treatment of contralateral patellar dislocation. Free-text analysis revealed several variables that influence the decision-making process.Conclusion:There are changes in trends related to management of first-time dislocation in adolescents. MRI, though not recommended for all patients with first-time dislocation, was obtained by 51% of respondents. The survey provides details of conservative treatment, including the role and duration of bracing and physical therapy. For first-time dislocation with an osteochondral fracture, concomitant patellar stabilization is preferred over isolated fixation. Simultaneous guided-growth for genu valgum correction is recommended. There were several variables that influenced the decision-making process and there were several areas of discordance. Further research studies on these parameters could potentially improve outcomes.

Comparison Between Surgical and Nonsurgical Treatment for Primary Patellar Dislocations in Adolescents: A Systematic Review and Meta-analysis of Comparative Studies

Background:Whether surgical or nonsurgical management is more appropriate for primary patellar dislocations (PPDs) in adolescents (younger than 18 years) remains controversial.Purpose:To compare the clinical outcomes of surgical versus nonsurgical treatment for adolescents and children with PPDs.Study Design:Systematic review; Level of evidence, 3.Methods:There were 2 reviewers who independently searched the PubMed, Embase, Ovid, and Cochrane databases for English-language studies of randomized controlled trials (RCTs), quasi-RCTs, and observational studies comparing surgical with nonsurgical treatment for PPDs. The primary outcomes were redislocations, the Kujala score, and the Knee injury and Osteoarthritis Outcome Score (KOOS), and the secondary outcome was subsequent surgery.Results:A total of 6 studies were included in our systematic review and meta-analysis. Among patients younger than 18 years, surgery was associated with a lower redislocation rate compared with nonsurgical treatment within 5 years of treatment (risk ratio [RR], 0.58 [95% CI, 0.37-0.91]; P = .02; I 2 = 47%) but not beyond 5 years (RR, 0.80 [95% CI, 0.59-1.07]; P = .14; I 2 = 34%). However, surgery resulted in worse Kujala and KOOS scores compared with nonsurgical treatment. Yet, the treatment difference between the 2 groups tended to decrease over time.Conclusion:The available evidence suggests that for adolescents with PPDs, surgery was superior to nonsurgical treatment in the short term to reduce the redislocation rate but resulted in poorer outcomes of knee function based on the Kujala and KOOS scores. However, the superiority of either surgical or nonsurgical treatment in adolescents did not appear to persist in the long term.

Recurrent patellar dislocations in adolescents result in decreased knee flexion during the entire gait cycle

To evaluate the kinematics/kinetics of the ankle, knee, hip in the sagittal plane in adolescents with recurrent patellar dislocation in comparison to a healthy control. Case-control study. Eighty-eight knees (67 patients) with recurrent patellar dislocation (mean age 14.8 years ± 2.8 SD) were compared to 54 healthy knees (27 individuals, 14.9 years ± 2.4 SD). Kinematics/kinetics of ankle, knee, hip, and pelvis were captured using 3D-gait analysis (VICON, 12 cameras, 200Hz, Plug-in-Gait, two force plates). One cycle (100%) consisted of 51 data-points. The mean of six trials was computed. The loading-response increased by 0.02s ± 0.01SE (10.8%) with dislocations (0.98% of total gait, P < 0.01). The mid-stance-phase decreased equally (P < 0.01). Dislocation decreased knee flexion during the entire gait cycle (P < 0.01), with the largest difference during mid-stance (9.0° ± 7.2 SD vs. 18.5° ± 6.7 SD). Dislocation increased plantar-flexion during loading response 4.1° ± 0.4 SE with (P < 0.01), afterward, the dorsal-extension decreased 3.2° ± 0.3 SE, (P < 0.01). Dislocation decreased hip flexion during all phases (P < 0.01). Maximal difference: 7.5° ± 0.5 SE during mid-stance. 80% of all patients developed this gait pattern. Internal moments of the ankle increased, of the knee and hip decreased during the first part of stance. Recurrent patellar dislocation decreases knee flexion during the loading-response and mid-stance phase. A decreased hip flexion and increased plantar-flexion, while adjusting internal moments, indicate a compensation mechanism. III.

No growth disturbance after trochleoplasty for recurrent patellar dislocation in adolescents with open growth plates

Aims and Objectives:Trochlear dysplasia is the most important risk factor to patellofemoral instability in adolescents, therefore trochleoplasty to reshape the trochlear groove is the treatment of choice in patients with severe trochlear dysplasia. However, in the presence of open growth plates there is a potential risk of injury of the distal femoral growth plate and subsequent growth disturbance. Therefore, most authors do not recommend trochleoplasty in skeletally immature patients. The effect of trochleoplasty on femoral growth when performed before closure of the distal femoral physis remains unclear.The hypothesis of the study was, that In patients with open growth plates and an expected growth of less than two years trochleoplasty does not cause growth disturbance of the distal femur.Materials and Methods:18 consecutive adolescents (18 knees) with open physes and severe trochlear dysplasia underwent trochleoplasty. Pre- and postoperative radiographic examination included AP and lateral views to assess leg axis and patella alta. Preoperatively a radiograph of the left hand was performed to measure skeletal age. MRI was performed to evaluate trochlear dysplasia and tibial tubercle-trochlear groove (TT-TG) distance. Evaluation included pre- and postoperative physical examination with evaluation of leg length and leg axis, Kujala score, Activity Rating Scale (ARS) and Tegner activity score.Results:The average age at the time of operation was 12.6 y (range, 12.2 - 13.3) in girls and 14.5 y (14.0 - 15.4) in boys. The average follow-up after operation was 2.3 years after surgery (range, 2.0 - 3.0 years). At follow-up in all patients the growth plates of the knee were closed. Impairment of growth of the distal femur was neither found clinically nor radiographically. No recurrent dislocation occurred. The median Kujala score and median VAS showed significant improvement (p < 0.01). The activity level according to the Tegner activity score did not change statistically significant.Conclusion:In this study, trochleoplasty as a treatment for patellofemoral instability in patients with open physes and an expected growth of not more than two years showed good clinical results without redislocation and no growth disturbance. Therefore, in selected adolescent patients with severe trochlear dysplasia trochleoplasty can be safely performed up to two years before the projected end of growth.

Early results of surgically treated patellar osteochondral fracture following patellar dislocation in adolescents: a case series of ten patients

Background Adolescents having knee ligaments laxity are more predisposed to patellar dislocation. Associated patellar osteochondral fractures (OCFs) denote a main complication. Many surgical options have been described to treat such injury. This study aimed to assess the early results of operated patellar OCFs following traumatic patellar dislocation in adolescents. Patients and methods Ten adolescent patients diagnosed to have patellar OCFs following traumatic patellar dislocation were surgically treated. After employing an initial arthroscopic examination, if the fragment was big enough, it was fixed by headless titanium compression screws, or else, the loose body was removed and the base was managed with microfracture. Preoperatively and postoperatively, patients evaluation was carried out using the visual analogue scale for pain and postoperatively via the International Knee Documentation Committee score. Results The mean follow-up was 24 months. Five of 10 patients underwent fixation, whereas the other five underwent loose fragments removal with microfracture. The median of visual analogue scale for pain scores demonstrated highly significant improvement (from 8.8 preoperative to 1.55 postoperative, P=0.002). The median International Knee Documentation Committee scores of the nonfixation and fixation group were 85.1 and 74.7, respectively (P=0.144). Conclusion According to this study, the surgical treatment for patellar OCFs following traumatic patellar dislocation in adolescents using headless titanium compression screws or excision and microfracture gave significant improvement. Studies with more patients’ numbers and longer follow ups are still necessary to properly assess the benefits of such management protocol. Level of Evidence: IV.

No Growth Disturbance After Trochleoplasty for Recurrent Patellar Dislocation in Adolescents With Open Growth Plates

Background: Trochlear dysplasia is the most important risk factor for patellofemoral instability among adolescents; therefore, trochleoplasty to reshape the trochlear groove is the treatment of choice for patients with high-grade trochlear dysplasia. However, in the presence of open growth plates, there is a potential risk of injury to the distal femoral growth plate and subsequent growth disturbance. As such, most authors do not recommend trochleoplasty for skeletally immature patients. The effect of trochleoplasty on femoral growth when performed before closure of the distal femoral physis remains unclear. Hypothesis: For patients with open growth plates and an expected growth <2 years, trochleoplasty does not cause growth disturbance of the distal femur. Study Design: Case series; Level of evidence, 4. Methods: Eighteen consecutive adolescents (18 knees) with open physes and severe trochlear dysplasia underwent thin flap trochleoplasty. Pre- and postoperative radiographic examination included anteroposterior and lateral views to assess leg axis and patella alta. A preoperative radiograph of the left hand was performed to measure skeletal age. Magnetic resonance imaging was performed to evaluate trochlear dysplasia and tibial tubercle–trochlear groove distance. Evaluation included pre- and postoperative physical examination with evaluation of leg length and leg axis, Kujala score, and Tegner activity score. Results: The median age at the time of operation was 12.6 years (range, 12.2-13.3 years) for girls and 14.5 years (14.0-15.4 years) for boys. The mean follow-up after operation was 2.3 years after surgery (range, 2.0-3.0 years). At follow-up for all patients, the growth plates of the knee were closed. Impairment of growth of the distal femur was found neither clinically nor radiographically. No recurrent dislocation occurred. The median Kujala score improved significantly from 67 (range, 54-75) preoperatively to 89.5 (range, 78-96) at follow-up (P < .01). The median visual analog scale showed significant pre- to postoperative improvement from 5 (range, 3-7) to 1 (range, 0-3) (P < .01). The activity level according to the Tegner activity score did not change significantly. Conclusion: In this study, trochleoplasty as a treatment for patellofemoral instability of patients with open physes and an expected growth of not more than 2 years showed good clinical results without redislocation and with no growth disturbance. Therefore, for selected adolescent patients with high-grade trochlear dysplasia, trochleoplasty can be safely performed up to 2 years before the projected end of growth.

Early Mpfl Repair After Patellar Dislocation in Adolescents Does Not Treat Anatomic Risk Factors for Repeat Instability

Early Mpfl Repair After Patellar Dislocation in Adolescents Does Not Treat Anatomic Risk Factors for Repeat Instability

Incidence of First-Time Lateral Patellar Dislocation: A 21-Year Population-Based Study.

Background:First-time lateral patellar dislocation is a common orthopaedic injury. The purposes of this study were to (1) evaluate the incidence of first-time lateral patellar dislocation in a geographically-determined population, (2) report trends over time in the incidence of dislocation, and (3) describe the rate of surgical treatment.Hypothesis:The rate of patellar dislocation is highest among adolescent patients.Study Design:Cohort study.Level of Evidence:Level 3.Methods:The study population included 609 individuals identified through a multidisciplinary geographic cohort county database who were diagnosed with first-episode lateral patellar dislocation between 1990 and 2010. The complete medical records were reviewed to confirm the diagnosis and to evaluate details of injury and treatment. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 US population. Poisson regression analyses were performed to examine incidence trends by age, sex, and calendar period.Results:The overall age- and sex-adjusted annual incidence of patellar dislocation was 23.2 (95% CI, 21.2-24.9) per 100,000 person-years. The annual incidence was similar between male and female patients and highest among adolescents aged 14 to 18 years (147.7/100,000 person-years). The mean age at dislocation was 21.4 ± 9.9 years, and 331 patients (54.4%) were female. During the study period, there was a significant decline in the incidence of patellar dislocation among men aged 19 to 25 years (P = 0.002) and girls aged 14 to 18 years (P = 0.025). Eighty patients received surgical treatment during the study period, including 66 patients (10.8%) for recurrent instability and 14 patients (2.3%) for acute osteochondral injury.Conclusion:With an annual incidence of 23.2 per 100,000 person-years, lateral patellar dislocation is a frequently encountered orthopaedic injury. The incidence of dislocation among adolescent patients in this cohort is higher than previously reported. Despite a decrease in the annual incidence of dislocation in adolescent girls, the overall incidence of patellar dislocation remained relatively constant over a 21-year observation period.Clinical Relevance:This study demonstrates that the incidence of patellar dislocation in adolescents is greater than previously reported.

Economic Decision Model for First-Time Traumatic Patellar Dislocations in Adolescents

Background: The surgical management of traumatic patellar dislocations in adolescents is associated with a lower rate of recurrent dislocations compared with nonoperative care. However, the attendant cost of surgery and the quality-of-life benefit of a surgical treatment strategy are unclear. Purpose: To compare the cost-utility of 3 management strategies for acute first-time patellar dislocations in adolescents: (1) nonoperative treatment only, (2) initial nonoperative treatment with surgery only for recurrent dislocations, and (3) immediate surgery. Study Design: Economic and decision analysis; Level of evidence, 2. Methods: A 10-year state-transition Markov model was constructed to compare the cost-utility of the 3 index treatment protocols. Utilities used to define health states were derived from a telephone interview of 60 adolescents with a history of acute patellar dislocations. The probability of transition between each health state was informed by the available literature. Direct costs were estimated using a statewide ambulatory surgery database, and indirect costs were estimated based on parental lost productivity. Effectiveness was expressed in quality-adjusted life years (QALYs). The principal outcome measure was the incremental cost-effectiveness ratio (ICER). Results: In the base case for our model, nonoperative treatment only was the least costly ($7300) but also the least effective (5.30 QALYs); initial nonoperative treatment with delayed surgery cost $10,500 for a 5.93 QALY benefit, while immediate surgical treatment cost $17,100 and provided 6.32 QALY benefits. Compared with nonoperative treatment only, initial nonoperative treatment with delayed surgery was associated with an ICER of $5100 per QALY. When immediate surgery was compared with a strategy of delayed surgery, immediate surgery provided incremental benefits at an ICER of $17,000 per QALY. The model was sensitive to the probability of surgical versus nonoperative treatment to achieve a full return to preinjury activity versus an intermediate lower state. When the probability of achieving a full return to preinjury activity with initial nonoperative treatment exceeds 47.5% (compared with 34.2% in the base case), then initial nonoperative treatment with delayed surgery is preferred to immediate surgery. Similarly, when the probability of achieving a full return to full preinjury activity with surgery falls below 51% (compared with 64% in the base case), then delayed surgery after initial nonoperative treatment is preferred. Conclusion: Immediate surgery and delayed surgical treatment are both cost-effective treatment options; however, immediate surgical treatment provides the highest QALY gains within a 10-year time horizon. Our model sensitivity analysis highlights the role of optimizing functional and quality-of-life benefits in the treatment of acute traumatic patellar dislocations. These findings have implications for clinical guidelines and policy decisions relating to adolescent patellar dislocations.

Long-Term Outcome After Operative Treatment of Traumatic Patellar Dislocation in Adolescents

Retrospective evaluation of the long-term outcomes after surgical treatment of traumatic patellar dislocations in adolescents and identification of possible predictive factors of poor outcomes. Retrospective clinical study. University Clinic, Level I Trauma Center. All 33 adolescents, with a mean age of 14.8 years, who were treated surgically after traumatic patellar dislocation between 1994 and 2006, were involved in this study. Mini-open medial reefing and arthroscopic lateral release. The clinical outcome was evaluated with the visual analogue scale, the Lysholm score, the Kujala score, and the Tegner activity level scale. On preoperative radiographs and magnetic resonance imaging scans, trochlear dysplasia and patella alta were assessed. The variables analyzed were sex, associated osteochondral injuries, the number of redislocations before surgery, and the number of redislocations after surgery. At the mean follow-up of 9.8 years, the mean Lysholm score was 82.6, the mean Kujala score was 84.4, the mean Tegner activity level was 4.8, and the mean visual analogue scale was 0.2. We found no significant differences in the subgroups regarding functional outcomes. Fifteen patients with patella alta and 4 patients with trochlear dysplasia were assessed radiologically. Redislocations after surgery were observed in 4 patients, 2 of them were female patients who exhibited quadriceps angles requiring tibial tubercle osteotomy to be performed after maturation. The techniques of mini-open medial reefing and lateral release demonstrate a good functional long-term outcome and effectively prevent recurrent instability. The major predictive factor for poor outcomes and redislocations is an inadequately addressed pathology. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Influence of arthroscopic lateral release on functional recovery in adolescents with recurrent patellar dislocation

The aim of this study is to prove the influence of the arthroscopic lateral release on functional recovery in adolescents with recurrent lateral dislocation of patella. From 2006 to 2009, arthroscopic release of the lateral retinaculum was done on 27 adolescent patients (24 women, 3 men) and 33 knees (in 6 patients on both knees). All of them were active in different sports. The severity of patellar subluxation and dislocation was analysed on X-ray; the Q angle, congruence angle, sulcus angle, patellofemoral angle and height ratio were measured. Functional scores (Lysholm, Kujala, Tegner) were measured preoperatively and postoperatively. The average duration of clinical and X-ray follow-up was 4.5years (range 3-6years). The mean age of the patients was 14.56years (range 11-18years). There was an average of 4.16 dislocations (range 2-28 dislocations) before surgery. The mean Lysholm score improved from 64 to 95 (p=0.0002), and the mean Kujala score improved from 66 to 94 (p<0.0001). Congruence angle and lateral patellofemoral angle improved but without any significant differences. Arthroscopic lateral release successfully treats recurrent patellar dislocations in adolescents, influences functional recovery and improves knee function.