Tibial Tubercle Osteotomy Research Articles

Combined MPFL Reconstruction with Tibial Tubercle Osteotomy and Repair of Patellar Cartilage Defect with Particulated Juvenile Articular Cartilage.

Combined MPFL Reconstruction with Tibial Tubercle Osteotomy and Repair of Patellar Cartilage Defect with Particulated Juvenile Articular Cartilage.

Distalization of tibial tubercle osteotomy is not necessary for patients with recurrent patellar dislocation accompanied by patella alta and increased TT–TG distance

BackgroundThe aim of this study is to determine whether distalization of the tibial tubercle is necessary for patients with recurrent patellar dislocation accompanied by patella alta and increased TT-TG.MethodsIn this retrospective study, all 70 patients (70 knees) with recurrent patellar dislocation accompanied by TT–TG distance ≥20 mm and patella alta (CD-I ≥ 1.4) were surgically treated using MPFLR combined with medialization of the tibial tubercle or medialization and distalization of the tibial tubercle in the Third Hospital of Hebei Medical University between 2017 and 2019. 33 patients(33 knees) received MPFLR combined with medialization of the tibial tubercle (MPFLR + TTm group), 37 patients(37 knees) received MPFLR combined with medialization and distalization of the tibial tubercle (MPFLR + TTm-d group). Evaluation indicators included knee injury and osteoarthritis prognostic score (KOOS) and Kujala score evaluation, congruence angle (CA), patellar tilt angle (PTA), TT-TG distance, Blackburne-Peel index (BP-I), Caton-Deschamps index (CD-I).ResultsA total of 70 knees (70 patients) with a mean follow-up time of 32 ± 6 months were evaluated in the present study. The postoperative, the PTA, CA, CD-I, BP-I, and TT-TG distance significantly improved in the two groups (P < 0.05), and there was no statistical difference between the two groups (>0.05). The KOOS and Kujala scores of the two groups at the last follow-up were significantly higher than the preoperative scores (P < 0.05), and there was no statistical difference between the two groups (P>0.05). No complications were noted in either group.ConclusionFor patients with recurrent patellar dislocation accompanied by increased TT-TG distance and patella alta, distalization is not needed and medialization is sufficient even in the presence of patella alta.

Both Medialization and Anteromedialization Tibial Tubercle Osteotomies are Effective Surgical Management for Skeletally Mature Patients with Patellofemoral Instability when Combined with Medial Patellofemoral Ligament Reconstruction.

The study aimed to compare the midterm outcomes of medialization and anteromedialization tibial tubercle osteotomies when used in the management of recurrent patellofemoral instability. The hypothesis is that both techniques would result in significant improvement for patellofemoral instability, but anteromedialization would result in a lower incidence of early osteoarthritis. In the cohort study, all skeletally mature patients aged 18 years old or younger who underwent tibial tubercle osteotomy for recurrent patellofemoral instability within a 10-year period in a single institution were included. All patients underwent either medialization or anteromedialization tibial tubercle osteotomy. The preoperative and postoperative outcomes of the tibial tubercle osteotomies were compared. All patients included in the study had a minimum of 5-year follow-up duration before the conclusion of the study. There was no statistically significant difference in the rates of preoperative and postoperative patellofemoral dislocation when either technique was employed (p = 0.999). Additionally, both the preoperative and postoperative Kujala scores were similar (p = 0.166 and p = 0.554, respectively). The knees did not have a statistically significant difference in their patellar tilt angles and tibial tubercle-trochlear groove distances preoperatively or postoperatively when either technique was used (p = 0.165 and 0.149, respectively). There was also no incidence of osteoarthritis identified in either of the groups (p = 0.999). Both anteriorization and anteromedialization tibial tubercle osteotomies were effective surgical management for patellofemoral instability when combined with medial patellofemoral ligament reconstruction. There were no significant differences in clinical, functional, and radiological outcomes when either medialization or anteromedialization tibial tubercle osteotomy was performed.

Anterior Closing Wedge Osteotomy for Failed Anterior Cruciate Ligament Reconstruction: State of the Art

The sagittal anatomy of the proximal tibia has a bearing on the forces exerted on the cruciate ligaments. A high posterior tibial slope is now a well-known risk factor causing failure of anterior cruciate ligament (ACL) reconstructions. The posterior slope can be calculated on short or full-length radiographs, MRI scans, or three-dimensional CT scans. Reducing the slope surgically by a sagittal tibial osteotomy is biomechanically protective for the ACL graft. An anterior closing wedge osteotomy may be contemplated when the lateral tibial slope is greater than 12°, in the setting of ACL reconstruction failure(s). Careful surgical planning to calculate the correction, taking into account knee hyperextension and patella height, is critical to avoid complications. It can be done above, at, or below the tibial tuberosity level. A transtuberosity correction can be done with or without a tibial tubercle osteotomy. This complex surgery can be conducted safely by meticulous execution to protect the posterior hinge and neurovascular structures and achieving stable fixation with staples. The limited literature available justifies the usage of anterior closing wedge osteotomy in appropriately selected patients.

Tibial Tubercle to Trochlear Groove Distance Measured by Posterior Condylar Reference Line on MRI Can Over-Evaluate Lateralization Deformity of Tibial Tubercle in Patients with Recurrent Patellar Dislocation.

Background: The tibial tubercle to trochlear groove (TT-TG) distance is currently considered as an indication for tibial tubercle osteotomy. While the influence of femoral condylar morphology on such measurement remains unclear. Methods: A total of 86 patients with patellar dislocation (PD) and 86 healthy individuals were enrolled. Femoral condylar morphology and the TT-TG distance measured by anatomical transepicondylar axis (TT-TGa), by surgical transepicondylar axis (TT-TGs), and by posterior condylar reference line (TT-TGp) were assessed by MRI. Unpaired t-test, Spearman, and Pearson correlation analysis were conducted. We determined the pathological value of the parameters and established a binary regression model. Results: The interclass correlation coefficients of all the TT-TG distances were greater than 0.75 in all types of trochlear dysplasia. The lateral/posterior femoral condyle was shorter and the medial/posterior condyle was longer in the study group (28.5 ± 3.3 and 35.2 ± 2.8, respectively) than in the control group (30.9 ± 2.7 and 33.5 ± 2.3, respectively). In the study group, the TT-TGp distance was greater than TT-TGs and TT-TGa distance (p < 0.001). The pathological value of the TT-TG distance was 13.0 mm. Each TT-TG distance revealed a significant OR with regard to PD. Conclusion: The TT-TGa, TT-TGs, and TT-TGp distance can be reliably measured by MRI even in patients with trochlear dysplasia. While the TT-TGp distance may overestimate the lateralization deformity of the tibial tubercle. Posterior femoral condylar dysplasia may be a reason for such overestimating. These findings have not been correlated to clinical outcomes and further studies are required.

Patellar Tendon Imbrication for the Treatment of Patella Alta in Skeletally Immature Patients

Patella alta is a major contributor to recurrent patellar instability, which is commonly seen in young athletes. Distalizing tibial tubercle osteotomy has been used for the correction of patella alta and patellar instability, but this procedure is contraindicated in the skeletally immature patient population, as it could lead to growth arrest of the proximal tibial physes. We propose a patellar tendon imbrication technique as a soft-tissue alternative to tibial tubercle osteotomy. When used with concomitant medial patellofemoral ligament reconstruction, we suggest this procedure may prove beneficial for the treatment of patellar instability in skeletally immature patients.

Thinner tuberosity osteotomy is more resistant to axial load in medial open-wedge distal tuberosity proximal tibial osteotomy: A biomechanical study

BackgroundThe purpose of this study was to investigate axial load resistance of the tibia depending on the thickness of tibial tuberosity osteotomy in medial open-wedge distal tuberosity proximal tibial osteotomy (OWDTO). The hypothesis is that a thin tibial tuberosity osteotomy shows high axial load resistance of the tibia. MethodsThe OWDTO model was constructed from imitation bones of the tibia. Distal tibial tuberosity osteotomy was performed with thicknesses of 7, 14, and 21 mm (n = 5 for each group). Cyclic axial-load fatigue tests were performed to investigate the strain at five measurement points on the OWDTO model. An axial-load failure test was also performed to investigate the maximum strain for failure. ResultsThe 7-mm OWDTO model showed a significantly lower stain range than the 14-mm model at the middle part of the lateral hinge (P = 0.0263, mean difference: −852.6 με), posterior part (P = 0.0465, mean difference: −1040.0 με), posterior tibial cortex (P < 0.0001, mean difference: −583.4 με), and plate (P = 0.0029, mean difference: −121.6 με). There were no significant differences in the strain at the tibial tuberosity between the groups. The axial load for complete failure was significantly higher in the 7-mm model than in the 21-mm model (P = 0.0010, mean difference: 2577.0 N). The failure points were at the lateral hinges. ConclusionsThinner distal tibial tuberosity osteotomy is more resistant to axial load and may be recommended for the prevention of tibial and lateral hinge fractures after OWDTO.

Osteotomies and Total Knee Arthroplasty: Systematic Review and Meta-Analysis.

Total knee replacement (TKA) is a frequent modality performed in patients with osteoarthritis. Specific circumstances can make it much more difficult to execute successfully, and additional procedures such as osteotomy may be required. The aim of this study was to perform a meta-analysis and systematic review of osteotomies combined with TKA. Methods: In June 2022, a search PubMed, Embase, Cochrane, and Clinicaltrials was undertaken, adhering to PRISMA guidelines. The search included the terms “osteotomy” and “total knee arthroplasty”. Results: Two subgroups (tibial tubercle osteotomy and medial femoral condyle osteotomy) were included in the meta-analysis. Further subgroups were described as a narrative review. The primary outcome showed no significant difference in favor to TTO. Secondary outcomes showed improved results in all presented subgroups compared to preoperative status. Conclusion: This study showed a significant deficit of randomized control trials treated with osteotomies, in addition to TKA, and a lack of evidence-based surgical guidelines for the treatment of patients with OA in special conditions: posttraumatic deformities, stiff knee, severe varus, and valgus axis or patella disorders.

Distal tibial tubercle osteotomy can lessen change in patellar height post medial opening wedge high tibial osteotomy? A systematic review and meta-analysis

ObjectiveMedial opening wedge high tibial osteotomy (MOWHTO) is a mainstream surgical method for treating early medial compartment knee osteoarthritis. Undesirable sequelae such as patella infera may happen following tuberosity osteotomy. We conducted this systematic review and meta-analysis to compare the change in patellar position after proximal tibial tubercle osteotomy (PTO) versus distal tibial tubercle osteotomy (DTO) intervention.MethodsThe 11 studies were acquired from PubMed, Medline, Embase and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan5.3. Mean differences, odds ratios and 95% confidence intervals were calculated. Cochrane Collaboration’s Risk of Bias Tool and Newcastle–Ottawa Scale were used to assess risk of bias.ResultsEleven observational studies were assessed. The methodological quality of the trials ranged from moderate to high. The pooled results of postoperative patellar height (Caton-Deschamps index and Blackburne-Peel index) and postoperative complications showed that the differences were statistically significant between PTO and DTO interventions. Patellar index ratios decreased significantly in the PTO groups, and 12 (9.2%) complications under DTO surgery and 2 (1.6%) complications under PTO surgery were reported. The differences of postoperative posterior tibial slope (angle) was not statistically significant, but postoperative posterior tibial slope of both groups increased. Sensitivity analysis proved the stability of the pooled results and the publication bias was not apparent.ConclusionsDTO in MOWHTO maintained the postoperative patellar height, and clinically, for patients with serious patellofemoral osteoarthritis, DTO can be preferred. Postoperative complications are easily preventable with caution. In view of the heterogeneity and small sample size, whether these conclusions are applicable should be further determined in future studies.

Insall proximal realignment with/without tibial tubercle osteotomy for recurrent patellar instability yields acceptable medium- to long-term results but risk of osteoarthritis progression is considerable

PurposeThe purpose of this study was to evaluate clinical and radiological results in patients operated for recurrent patellar instability with a surgical approach consisting of Insall proximal realignment with/without tibial tubercle osteotomy (TTO).MethodsPatients that underwent surgery for recurrent patellar instability at one centre with a uniform technique between 2004 and 2020 were included. Eligible patients were assessed by clinical examination and the disease-specific Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0). Pre- and postoperative radiographs were analysed for patellofemoral osteoarthritis (OA) according to Iwano. Preoperative Magnetic Resonance Imaging (MRI) and radiographs were analysed for anatomical risk factors for patellar instability. Student t-test, chi-square test and ANOVA-analyses were used to investigate whether anatomical risk factors and/or patient characteristics could predict an inferior outcome.ResultsForty-six patients (47 knees) were included at a mean follow-up time of 6.6 years (SD 4.6; range 1–17). Mean BPII 2.0 score was 60.4 (SD 18.4; range 26–98), and 10.6% (n = 5) had suffered a postoperative redislocation. Progression to evident patellofemoral OA was seen in 15% of the patients (p < 0.05). The presence of pathoanatomic risk factors did not correlate with recurrent postoperative instability or inferior BPII 2.0 score at the final evaluation.ConclusionPatients treated with the current approach reported acceptable medium- to long-term results, but the risk of patellofemoral OA progression is significant. These findings add to the knowledge of expected outcomes after procedures involving Insall proximal realignment, and can guide clinical decision making for surgeons using similar methods.Level of evidenceLevel IV, case series.

Poster 232: Performing a Concomitant Tibial Tubercle Osteotomy During Primary Medial Patellofemoral Ligament Reconstruction Does Not Lead to Increased Post-Operative Complication Rates

Objectives:Tibial tubercle osteotomy is utilized to unload cartilage defects and/or to correct malalignment in the setting of patellofemoral instability and/or chondrosis. Controversy remains regarding the indications for TTO as an adjunct to soft tissue stabilization for patella instability. Our purpose was to evaluate safety and efficacy of MPFLR with or without concomitant tibial tubercle osteotomy (TTO). Our hypothesis was that adding TTO to MPFLR would lead to lower revision instability surgical rates but higher rates of overall re-operation, complication, and cost.Methods:We queried the MarketScan database in order to identify patients who underwent primary MPFLR from 2007-2015. Patients were stratified into cohorts based on concomitant TTO performed on the same day as index MPFLR. To minimize the effect of potential confounding on the direct comparison of patients undergoing the two procedures, a propensity-score match (PSM) was utilized. A greedy nearest-neighbor algorithm was employed to match patient cohorts with a 7:1 MPFLR to MPFLR + TTO ratio. Reoperations, complications, and costs were followed for two years post-index procedure. Patients without laterality codes were excluded. Results were analyzed statistically.Results:This study identified 968 patients who underwent primary MPFLR. Patients were stratified into two groups: 1) MPFLR only or 2) MPFLR + TTO. After matching the cohorts, mean age, sex distribution, and rates of baseline diabetes, hyperlipidemia, hypertension, tobacco use, and obesity were similar. Patients in the two cohorts experienced similar rates of postoperative complications (MPFLR + TTO: 9.9%, MPFLR: 8.7%, p= 0.6694). Rates of dislocation (MPFLR + TTO: 5.8%, MPFLR: 4.3%, p = 0.4434), stiffness (MPFLR + TTO: 0.8%, MPFLR: 2.5%, p = 0.2538), infection (MPFLR + TTO: 0.8%, MPFLR: 0.6%, p = 0.7559), and wound complication (MPFLR + TTO: 0.8% vs MPFLR: 0.8%, p = 1.000) were similarly low. Performing a concomitant TTO decreased revision surgery for instability (revision MPFLR) rates (6.6% vs 11.1%, p = 0.1327); however, this difference was not statistically significant. Hardware removal (MPFLR + TTO: 9.9%, MPFLR: 1.9%, p < 0.0001) was higher in the MPFLR + TTO cohort. Patients who underwent a concomitant TTO were associated with higher payments through 2 years of index surgery when compared to MPFLR only patients ($25,740 vs $17,727, p < 0.0001).Conclusions:Concomitant TTO at the time of MPFLR does not lead to increased post-operative complications. The addition of TTO to MPFLR reduced revision surgical rates for instability from 11.1 to 6.6% but this difference was not statistically significant. Combination TTO/MPFLR led to higher payments through 2 years. Further research is needed to refine the indications for TTO as a adjunct procedure to MPFLR and its impact on long-term stability and failure rates.Table 1.Demographics and Baseline ComorbiditiesTable 2.Postoperative Complications - within 90 daysTable 3.Quality OutcomesTable 4.Non-obese vs Obese Subgroup AnalysisTable 6.Age <30 vs Age >30 Subgroup AnalysisTable 7.Non-smoker versus Smoker Subgroup Analysis

Poster 202: Patellar Stabilization Procedures Not Performed to Address Alta Decrease Patellar Height

Poster 202: Patellar Stabilization Procedures Not Performed to Address Alta Decrease Patellar Height

Descriptive Epidemiology of a Surgical Patellofemoral Instability Population of 492 Patients.

Background:Patellofemoral instability (PFI) occurs most commonly in pediatric and adolescent patients, with evolving indications for surgery and changes in surgical techniques over the past decade.Purpose:To characterize the demographic, clinical, and radiologic characteristics of a large cohort of patients undergoing PFI surgery and investigate longitudinal trends in techniques utilized over a 10-year period at a tertiary-care academic center.Study Design:Case series; Level of evidence, 4.Methods:Electronic medical records of patients younger than 25 years of age who underwent primary surgery for lateral PFI from 2008 to 2017 at a single center by 1 of 5 different sports medicine surgeons were retrospectively reviewed. Demographic, clinical, and radiographic parameters of instability were analyzed. Routine surgical techniques included medial retinacular plication/reefing/repair (MRP), medial patellofemoral ligament reconstruction (MPFLR), tibial tubercle osteotomy (TTO), or a combination thereof, with or without lateral retinacular release (LR) or lateral retinacular lengthening (LRL). Exclusion criteria, selected for potentially altering routine surgical indications or techniques, included fixed/syndromic PFI, a formally diagnosed collagen disorder, cases in which a chondral/osteochondral shear fragment underwent fixation or was >1 cm in diameter, and body mass index >30 kg/m2.Results:Of the 492 study patients (556 knees; 71% female; median age, 15.2 years; 38% open physes), 88% were athletes, with the most common sports participated in being soccer, basketball, dance, football, gymnastics, and baseball/softball. While 91% of the cohort had recurrent dislocations, the 9% with primary dislocations were more likely to have small osteochondral fractures/loose bodies (P < .001). Female patients were younger (P = .002), with greater patellar tilt (P = .005) than male patients. Utilization of MPFLR and TTO increased significantly over the study period, while use of MRP+LR decreased.Conclusion:Most patients younger than 25 years of age who underwent PFI surgery were skeletally immature, female, and athletes and had recurrent dislocations. The <10% who had primary dislocations and underwent surgery were likely to have osteochondral fractures. Surgical techniques have changed significantly over time, with increasing use of TTO and MPFLR, while the use of MRP+LR/LRL has significantly decreased.

Poster 235: Surgical Management of Patellar Instability in Adolescents with High Grade Trochlear Dysplasia

Objectives:High-grade trochlear dysplasia (HGTD) has previously been identified as a risk factor for failure of surgical management of patellofemoral instability (PFI). However, limited data exists on the influence of the type of surgical procedure performed on postoperative outcomes in these patients. The purpose of this study was to identify the rates of failure of primary PFI surgery in patients with HGTD compared to those without HGTD and to assess the effect of the type of surgery on recurrent instability and return to OR.Methods:We retrospectively reviewed patients aged ≤19 years who underwent primary surgery for PFI at our institution between 2008 and 2017. Patients underwent procedures including medial retinacular plication (MRP), medial patellofemoral ligament reconstruction (MPFLR), tibial tubercle osteotomy (TTO), or combined procedures. We excluded patients with incomplete imaging data, BMI >30kg/m2, those that underwent surgery for fixation of a chondral fracture >1cm, and patients with a diagnosis of syndromic disorder. Trochlear dysplasia was evaluated based on pre-operative MRI. Patients were divided between those that had HGTD and those without HGTD. Comparisons were made between the two groups and logistic regression analysis was utilized to determine if surgery category was associated with rate of recurrence in the HGTD patients.Results:Three-hundred three patients, average age 15.1 years, underwent primary surgical stabilization for PFI with median follow up time of 3.0 years. Forty-nine percent (149/303) of the cohort had HGTD. Demographics were comparable between HGTD groups (Table 1). When compared to the patients without HGTD, patients with HGTD showed similar rates of recurrent instability, return to the OR for instability, and return to the OR for other reasons. Looking at patients with just HGTD, there was a significant association between surgery type and outcomes (Table 2). HGTD patients who underwent MPFLR had a 63% decrease in the odds of experiencing recurrent instability compared to those undergoing MRP (OR=0.37; p=0.03). Similarly, the TTO surgery group had an 80% decrease in the odds of experiencing recurrent instability compared to patients undergoing MRP (OR=0.20; p=0.002).Conclusions:While adolescents with PFI and HGTD overall have similar results after surgical stabilization, there is a significant effect of the type of surgery performed. Patients with HGTD that underwent MRP had significantly more instability and return to the OR for instability surgeries than patients that underwent other procedures. Based on this data, adolescents with PFI and HGTD should be considered for more powerful surgeries to limit the risk of recurrence or return to the OR.Table 1.Patient Demographics and Outcomes Compared Between Trochlear Dysplasia Groups (n=303)Table 2.Outcomes of Patients with HGTD Compared by Type of Surgery (N=149).

Poster 234: Radiographic Predictors of Failure of Patellar Instability Surgery in Adolescents

Objectives:Adolescents often benefit from surgical management of recurrent patellofemoral instability (PFI). However, the debate continues as to which preoperative radiographic factors can be used to predict the risk of failure of patellar stabilization surgery. The purpose of this study was to determine the rate of failure, defined as recurrence of instability, in a large cohort of adolescent athletes undergoing primary surgery for PFI, and to identify preoperative radiographic risk factors for recurrence.Methods:We retrospectively reviewed patients aged 19 years and younger who underwent primary surgery for PFI at our institution between 2008 and 2017. Patients underwent surgical procedures including medial retinacular plication (MRP), medial patellofemoral ligament reconstruction (MPFLR), tibial tubercle osteotomy (TTO), or a combination thereof. Preoperative magnetic resonance imaging (MRI) studies were reviewed and radiographic parameters were recorded. We excluded patients with incomplete imaging data, BMI >30kg/m2, those that underwent surgery for fixation of a chondral fracture >1cm, and patients with a diagnosis of syndromic disorder. Demographic and radiographic variables were compared between patients who experienced recurrence of instability and those that did not. Logistic regression was utilized to determine if any imaging characteristics were associated with recurrent instability while controlling for age and sex.Results:Three-hundred three patients, average age 15.1 years, underwent primary surgical stabilization for PFI with median follow up time of 3.0 years. At final follow-up, 25% of patients (76/303) experienced recurrent instability with 41 patients (14%) requiring additional surgery because of this instability. Patients who had recurrent instability were younger (14.3vs15.4 years; p<0.001) and were more likely to have undergone MRP surgery alone (66% vs 35%; p<0.001) (Table 1). They were also more likely to have an open physeal status (62% vs 49%; p<0.001), a larger sulcus angle (163.9 vs 159.2; p<0.001), a larger patellar tilt angle (26.3 vs 23.6; p=0.04), and larger Caton-Deschamps ratio (1.3 vs 1.2; p=0.03) (Table 2). Each additional degree of sulcus angle increased the odds of recurrent instability by 5% (OR=1.05; p=0.002). Notably, each additional year of age at the time of surgery, decreased the odds of failure by 23% (OR=0.77; p<0.001).Conclusions:In conclusion, 25% of adolescents experienced recurrent instability after primary patellar stabilization surgery. These patients who failed initial surgical treatment were younger and had more MRP procedures. Radiographically, they had more open physes, flatter trochleae, more patellar tilt, and larger patellar height. This information can be used to guide treatment decisions and inform the risk of failure of surgical stabilization procedures in adolescents with PFI.Table 1.Patient Demographics by Presence or Absence of Recurrent Instabillity (N=303).Table 2.Imaging Measurements by Presence or Absence of Recurrent Instability (N=303).

Outcomes of Allograft Medial Patellofemoral Ligament Reconstruction in Children and Adolescents with Hypermobility.

IntroductionMedial patellofemoral ligament (MPFL) reconstruction is used to treat patellofemoral instability either in isolation or in combination with other procedures. Use of allograft can preserve native tissue in children and can be advantageous in patients with connective tissue disorders, including ligamentous laxity. There is limited evidence regarding functional outcomes of allograft MPFL reconstruction in children and adolescents. This study aimed to assess the short to mid-term results of allograft MPFL reconstruction in children with hypermobility at a tertiary pediatric orthopedic center.Materials and Methods:We retrospectively reviewed all children and adolescents who had undergone allograft MPFL reconstruction over 4 years. The primary outcome measure was the validated Kujala score for patellofemoral disorders. The secondary outcome measures included complications such as redislocation of the patella needing revision surgery. Patients with hypermobility were quantified using Beighton criteria. Statistical analysis was performed using Graph Pad Prism (V6).ResultsBetween 2012 and 2016, the senior author performed 76 allograft MPFL reconstructions in 57 patients. Nineteen patients had bilateral surgery. The mean age was 14 (7–16) years with a female: male ratio of 3:1. The mean Beighton score was 7. Hypermobility was part of a syndrome in ten patients. The mean follow-up was 3 (1–4) years. Nine patients had trochleoplasty and six patients had tibial tubercle osteotomy, in addition to allograft MPFL reconstruction. These fifteen patients, who had additional procedures, were excluded during the analysis of the outcome measures. The mean Kujala score was 89 (80–100). The overall complication rate was 11% (9/76). These included two patella fractures and seven (9%) patients with recurrent instability needing revision surgery. There was no significant difference in complication rates between syndromic and nonsyndromic patients (P = 0.9).ConclusionOur study shows excellent short to mid-term functional outcomes of allograft MPFL reconstruction in children and adolescents with hypermobility.

Poster 214: Posterior Tibial Slope Reducing Osteotomy in Complex Revision Anterior Cruciate Ligament Reconstruction

Poster 214: Posterior Tibial Slope Reducing Osteotomy in Complex Revision Anterior Cruciate Ligament Reconstruction

Tibial tubercle osteotomy indications and surgical techniques

Tibial tubercle osteotomy indications and surgical techniques

Paper 53: Comparing Graft Choice in Medial Patellofemoral Ligament Reconstruction

Objectives:Disruption of the medial patellofemoral ligament (MPFL) may lead to recurrent lateral patellar dislocation and patellofemoral chondral injury. Optimal graft choice for MPFL reconstruction in the surgical treatment of patellar instability is unknown. While autograft remains readily available, easily harvested, and of lower cost, allograft is a viable alternative and portends several benefits over autograft. Autograft may provide superior strength or lower re-tear rate, but allograft has been shown to have similar outcomes with less donor site morbidity in some series. Overall, there is a paucity of research comparing autograft vs allograft in MPFL reconstruction. Prior studies have been limited by small sample sizes, incomplete data, or heterogeneous patient population. The objectives of this study were to compare outcomes scores, return to activity and revision rates between allograft and autograft in MPFL reconstruction. The authors hypothesized that there would be no significant difference in outcomes between those who received an allograft and those who received an autograft in MPFL reconstruction.Methods:Patients who underwent isolated MPFL reconstruction with allograft or autograft at a single institution between 2013-2020 were retrospectively reviewed. Patients with a follow-up of less than 2 years were excluded, along with those who underwent concomitant tibial tubercle osteotomy or trochleoplasty. Patients were contacted to complete functional assessments including the Single Assessment Numeric Evaluation (SANE), Visual Analog Scale for pain (VAS), and International Knee Documentation Committee (IKDC) scores. Patient demographics and complications were also reviewed. Outcomes were compared between those that underwent allograft and autograft MPFL reconstructionResults:Out of the fourty-six patients that were retrospectively reviewed, thirty-one (67.4%) patients underwent allograft reconstruction, while fifteen (32.6%) patients underwent autograft reconstruction. There were no differences between the two groups in age at surgery (25.2 years old in allograft vs 26.3 years old in autograft group, P=0.726), sex ratio (19F/12M in allograft and 9F/6M in autograft, P=1.000), or BMI (27.0 in allograft and 24.8 in autograft, P=0.179).There was a mean follow up duration of 4.57 years in the allograft group and 4.83 years in the autograft group (P=0.672), with an overall response rate of 70.2%. There were no differences between the two groups when assessing subjective pain using SANE (66.7 in allograft vs 74.5 in autograft, P=0.334) or VAS score (35.7 in allograft vs 22.9 in autograft, P=0.110). Further there were no differences in patient outcomes as assessed by IKDC score (68.3 in allograft vs 76.2 in autograft, P=0.247). Patients who received an allograft returned to activity at an average of 5.9 months, while patients who received an autograft returned to activity at an average of 5.2 months (P=0.416). One patient in the allograft group required revision surgery (P=0.246).Conclusions:Both allograft and autograft remain viable options in MPFL reconstruction. There were no significant differences in failure rates, PROs, pain, or time to return to play between allograft and autograft MPFL reconstruction in this series.

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.