Very Few ACGME-accredited Orthopaedic Surgery Residency Programs Have Web-accessible Leave Policies Dedicated to Parental Leave for Residents, Despite ACGME Requirements.

BACKGROUND: The Accreditation Council for Graduate Medical Education (ACGME) requires that all graduate medical education (GME) programs provide at least 6 paid weeks off for medical, parental, and caregiver leave to residents. However, it is unclear whether all orthopaedic residency programs have adapted to making specific parental leave policies web-accessible since the ACGME's mandate in 2022. This gap in policy knowledge leaves both prospective and current residents in the dark when it comes to choosing residency programs, and knowing what leave benefits they are entitled to when having children during training via birth, surrogacy, adoption, or legal guardianship. QUESTIONS/PURPOSES: (1) What percentage of ACGME-accredited orthopaedic surgery residency programs provide accessible parental leave policies on their program's website, their GME website, and through direct contact with their program's administration? (2) What percentage of programs offer specific parental leave policies, generic leave policies, or defer to the Family and Medical Leave Act (FMLA)? METHODS: As indicated in the American Medical Association's 2022 Freida Specialty Guide, 207 ACGME-accredited orthopaedic residency programs were listed. After further evaluation using previous literature's exclusion criteria, 37 programs were excluded based on osteopathic graduate rates. In all, 170 ACGME-accredited allopathic orthopaedic surgery residency programs were identified and included in this study. Three independent reviewers assessed each program website for the presence of an accessible parental leave policy. Each reviewer accessed the program's public webpage initially, and if no parental leave policy was available, they searched the institution's GME webpage. If no policy was found online, the program administrator was contacted directly via email and phone. Available leave policies were further classified into five categories by reviewers: parental leave, generic leave, deferred to FMLA, combination of parental and FMLA, and combination of parental and generic leave. RESULTS: Our results demonstrated that 6% (10 of 170) of orthopaedic residency programs had policy information available on their program's main orthopaedic web page. Fifty nine-percent (101 of 170) of orthopaedic residency programs had a clearly stated policy on their institution's GME website. The remaining 35% (59 of 170) had no information on their public website and required direct communication with program administration to obtain policy information. After directly contacting program administration, 12% (21 of 170) of programs responded to researchers request with a PDF explicitly outlining their policy. Twenty-two percent (38 of 170) of programs did not have an accessible policy available. Of the programs that had available policies, a total of 53% (70 of 132) of programs were categorized as offering explicit parental leave policies, 9% (12 of 132) were categorized as offering general leave policies, and 27% (36 of 132) deferred to FMLA. Seven percent (9 of 132) offered combined parental leave policies with FMLA, and 4% (5 of 132) offered combined general leave policies with FMLA. CONCLUSION: Although most ACGME-accredited allopathic orthopaedic surgery residency programs met the ACGME requirement of written parental leave policies in 2023, a small minority of programs have clear, accessible parental leave policies provided on their webpage. CLINICAL RELEVANCE: Parental leave policies should be easily accessible to prospective and current trainees and should clearly state compensation and length of leave. Ensuring orthopaedic surgery residency programs provide accessible and transparent parental leave policies is important for maintaining diversity in prospective applicants and supporting the work-life balance of current residents.

The Adductor Sling Technique for Pediatric Medial Patellofemoral Ligament Reconstruction Better Resists Dislocation Loads When Compared With Adductor Transfer at Time Zero in a Cadaveric Model.

Purpose: To characterize the ability of the intact medial patellofemoral ligament (MPFL) and the adductor transfer and adductor sling MPFL reconstruction techniques to resist subluxation and dislocation in a cadaveric model. Methods: Nine fresh-frozen cadaveric knees were placed on a custom testing fixture with the femur fixed parallel to the floor, the tibia placed in 20° of flexion, and the patella attached to a load cell. The patella was displaced laterally, and subluxation load (in newtons), dislocation load (in newtons), maximum failure load (in newtons), patellar displacement at failure, and mode of failure were recorded. Testing was conducted with the MPFL intact and after the adductor sling and adductor transfer reconstruction techniques. Statistical analysis was completed using 1-way repeated-measures analysis of variance with the Holm-Sidák post hoc test. Results: The subluxation load was not significantly different between groups. The native MPFL dislocation load was significantly higher than the dislocation loads of both reconstruction techniques, but no significant difference between the dislocation loads of the 2 reconstruction techniques occurred. The native MPFL failure load was significantly higher than the failure loads of both reconstruction techniques. The adductor sling failure load was significantly higher than the adductor transfer failure load. The mode of failure varied across groups. The native MPFL failed by femoral avulsion, patellar avulsion, and midsubstance tear. The main mode of failure for adductor transfer was pullout, whereas failure for the adductor sling technique most often occurred at the sutures. Most of the native MPFLs and all adductor sling reconstructions failed after dislocation. The adductor transfer reconstructions were much more variable, with failures spanning from before subluxation through dislocation. Conclusions: Our cadaveric model showed that neither the adductor transfer technique nor the adductor sling technique restored failure load to that of the native condition. There was no significant difference in the subluxation or dislocation loads between the 2 MPFL reconstructions, but the adductor sling technique resulted in a higher load to failure. The adductor transfer technique frequently failed before subluxation or dislocation when compared with the adductor sling technique and the native MPFL. Clinical Relevance: The best technique for MPFL reconstruction in patients with open physes is a topic of debate. Given the long-term consequences of MPFL injury and potential for growth plate disturbance, it is important to study MPFL reconstruction techniques thoroughly, including in the laboratory setting.

CSF Findings in Relation to Clinical Characteristics, Subtype, and Disease Course in Patients With Guillain-Barré Syndrome.

BACKGROUND AND OBJECTIVES: To investigate CSF findings in relation to clinical and electrodiagnostic subtypes, severity, and outcome of Guillain-Barré syndrome (GBS) based on 1,500 patients in the International GBS Outcome Study. METHODS: Albuminocytologic dissociation (ACD) was defined as an increased protein level (>0.45 g/L) in the absence of elevated white cell count (<50 cells/µL). We excluded 124 (8%) patients because of other diagnoses, protocol violation, or insufficient data. The CSF was examined in 1,231 patients (89%). RESULTS: In 846 (70%) patients, CSF examination showed ACD, which increased with time from weakness onset: ≤4 days 57%, >4 days 84%. High CSF protein levels were associated with a demyelinating subtype, proximal or global muscle weakness, and a reduced likelihood of being able to run at week 2 (odds ratio [OR] 0.42, 95% CI 0.25-0.70; p = 0.001) and week 4 (OR 0.44, 95% CI 0.27-0.72; p = 0.001). Patients with the Miller Fisher syndrome, distal predominant weakness, and normal or equivocal nerve conduction studies were more likely to have lower CSF protein levels. CSF cell count was <5 cells/µL in 1,005 patients (83%), 5-49 cells/µL in 200 patients (16%), and ≥50 cells/µL in 13 patients (1%). DISCUSSION: ACD is a common finding in GBS, but normal protein levels do not exclude this diagnosis. High CSF protein level is associated with an early severe disease course and a demyelinating subtype. Elevated CSF cell count, rarely ≥50 cells/µL, is compatible with GBS after a thorough exclusion of alternative diagnoses. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that CSF ACD (defined by the Brighton Collaboration) is common in patients with GBS.

Establishing minimal detectable change thresholds for the international knee documentation committee and Kujala scores at one and two years after patellofemoral joint arthroplasty.

PURPOSE: To define the minimal detectable change (MDC) for the international knee documentation committee (IKDC) and Kujala scores one and two years after patellofemoral joint arthroplasty (PFA). METHODS: A distribution-based method (one-half the standard deviation of the mean difference between postoperative and preoperative outcome scores) was applied to establish MDC thresholds among 225 patients undergoing primary PFA at a single high-volume musculoskeletal-care center. Stability of change in MDC achievement was explored by quantifying the proportion of achievement at one- and two-year postoperative timepoints. Multivariable logistic regression analysis was performed to explore the association between sociodemographic and operative features on MDC achievement. RESULTS: MDC thresholds for the Kujala score were 10.3 (71.1% achievement) and 10.6 (70.4% achievement) at one- and two years, respectively. The MDC thresholds for the IKDC score were 11.2 (78.1% achievement) and 12.3 (69.0% achievement) at one- and two years, respectively. Predictors of achieving the MDC for the Kujala and IKDC scores at both time points were lower preoperative Kujala and IKDC scores, respectively. Preoperative thresholds of ≤ 24.1 and 7.6 for the Kujala and IKDC scores, respectively, were associated with a 90% MDC achievement probability. When preoperative thresholds approached 64.3 and 48.3 for the Kujala and IKDC, respectively, MDC achievement probability reduced to 50%. CONCLUSION: The MDC thresholds for the Kujala and IKDC scores two years after PFA were 10.6 and 12.3, respectively. Clinically significant health status changes were maintained overall, with a slight decrease in achievement rates between one and two years. MDC achievement was associated with disability at presentation, and several probability-based preoperative thresholds were defined. These findings may assist knee surgeons with patient selection and the decision to proceed with PFA by better understanding the patient-specific propensity for MDC achievement. LEVEL OF EVIDENCE: IV, retrospective case series.

Does Ligamentous Laxity Protect Against Chondral and Osteochondral Injuries in Patients With Patellofemoral Instability?

Background: Many patients undergoing medial patellofemoral ligament (MPFL) reconstruction for patellofemoral instability have chondral or osteochondral injuries requiring treatment. Hypothesis: In patients undergoing MPFL reconstruction for patellofemoral instability, those with ligamentous laxity (LAX) would be less likely to have chondral or osteochondral defects requiring surgical intervention compared with those with no laxity (NLX). Study Design: Cohort study; Level of evidence, 2. Methods: Included were 171 patients with patellofemoral instability (32 men, 139 women; mean age, 22 years [range, 11-57 years]) who underwent MPFL reconstruction between 2005 and 2015. Patients with a Beighton-Horan score ≥5 were considered LAX (n = 96), while patients with scores <5 were considered NLX (n = 75). Preoperative magnetic resonance images were evaluated to determine the presence, size, and location of chondral or osteochondral injury as well as the grade according to the Outerbridge classification. Documented anatomic measurements included tibial tubercle-trochlear groove (TT-TG) distance, Caton-Deschamps Index (CDI) for patellar height, and the Dejour classification for trochlear dysplasia. Results: Of the 171 patients, 58 (34%) required a surgical intervention for a chondral or osteochondral defect: chondroplasty (29/58; 50%), particulated juvenile cartilage implantation (18/58; 31%), microfracture (16/58; 28%), osteochondral fracture fixation (2/58; 3.4%), and osteochondral allograft (2/58; 3.4%). While there was no statistical difference in the proportion of patellar chondral or osteochondral injuries between patients with NLX (58%) versus LAX (67%) (P = .271), there was a significantly higher rate of patellar grade 3 or 4 injuries in the NLX (74%) versus LAX (45%) group (P = .004). Similarly, there was no difference in femoral chondral or osteochondral injury rates between groups (P = .132); however, femoral grade 3 or 4 injuries were significantly higher in the NLX (67%) versus the LAX (13%) group (P = .050). After adjusting for age, sex, radiographic parameters (TT-TG distance and CDI), and trochlear morphology, patients with LAX were 75% less likely to have had a grade 3 or 4 patellar cartilage injury compared with patients with NLX (P = .006). Conclusion: For patients who sustained patellar or femoral chondral or osteochondral injuries, compared with their counterparts with NLX, patients with LAX were less likely to have severe (grade 3 or 4) injuries requiring surgical intervention.

Many Radiographic and Magnetic Resonance Imaging Assessments for Surgical Decision Making in Pediatric Patellofemoral Instability Patients Demonstrate Poor Interrater Reliability.

PURPOSE: To evaluate the interrater reliability of several common radiologic parameters used for patellofemoral instability and to attempt to improve reliability for measurements demonstrating unacceptable interrater reliability through consensus training. METHODS: Fifty patients with patellar instability between the ages of 10 and 19 years were selected from a prospectively enrolled cohort. For measurements demonstrating unacceptable interrater reliability (intraclass correlation coefficient [ICC]: <0.6), raters discussed consensus methods to improve reliability and re-examined a subset of 20 images from the previous set of images. If reliability was still low after the second round of assessment, the measure was considered unreliable. RESULTS: Of the 50 included subjects, 22 (44%) were male and the mean age at the time of imaging was 14 ± 2 years. With 1 or fewer consensus training sessions, the interrater reliability of the following radiograph indices were found to be reliable: trochlea crossing sign (ICC: 0.625), congruence angle (ICC: 0.768), Caton-Deshamps index (ICC: 0.644), lateral patellofemoral angle (ICC: 0.768), and mechanical axis deviation on hip-to-ankle alignment radiographs (ICC: 0.665-0.777). Reliable magnetic resonance imaging (MRI) indices were trochlear depth (ICC: 0.743), trochlear bump (ICC: 0.861), sulcus angle (ICC: 0.684), patellar tilt (ICC: 0.841), tibial tubercle to trochlear groove distance (ICC: 0.706), effusion (ICC: 0.866), and bone marrow edema (ICC: 0.961). CONCLUSIONS: With 1 or fewer consensus training sessions, the interrater reliability of the following patellofemoral indices were found to be reliable for trochlear morphology: trochlea crossing sign and congruence angle on radiograph and trochlear depth, trochlear bump, and sulcus angle on MRI. Reliable patellar position measurements included: Caton-Deshamps index and lateral patellofemoral angle on radiograph and patellar tilt and tibial tubercle to trochlear groove distance on MRI. Additional global measurements (e.g., mechanical axis deviation on standing radiographs) and MRI assessments demonstrated acceptable reliability. LEVEL OF EVIDENCE: II, prospective diagnostic study.

Electrodiagnosis of Guillain-Barre syndrome in the International GBS Outcome Study: Differences in methods and reference values.

OBJECTIVE: To describe the heterogeneity of electrodiagnostic (EDx) studies in Guillain-Barré syndrome (GBS) patients collected as part of the International GBS Outcome Study (IGOS). METHODS: Prospectively collected clinical and EDx data were available in 957 IGOS patients from 115 centers. Only the first EDx study was included in the current analysis. RESULTS: Median timing of the EDx study was 7 days (interquartile range 4-11) from symptom onset. Methodology varied between centers, countries and regions. Reference values from the responding 103 centers were derived locally in 49%, from publications in 37% and from a combination of these in the remaining 15%. Amplitude measurement in the EDx studies (baseline-to-peak or peak-to-peak) differed from the way this was done in the reference values, in 22% of motor and 39% of sensory conduction. There was marked variability in both motor and sensory reference values, although only a few outliers accounted for this. CONCLUSIONS: Our study showed extensive variation in the clinical practice of EDx in GBS patients among IGOS centers across the regions. SIGNIFICANCE: Besides EDx variation in GBS patients participating in IGOS, this diversity is likely to be present in other neuromuscular disorders and centers. This underlines the need for standardization of EDx in future multinational GBS studies.

Particulated Juvenile Articular Cartilage and Matrix-Induced Autologous Chondrocyte Implantation Are Cost-Effective for Patellar Chondral Lesions.

PURPOSE: To compare the cost-effectiveness of nonoperative management, particulated juvenile allograft cartilage (PJAC), and matrix-induced autologous chondrocyte implantation (MACI) in the management of patellar chondral lesions. METHODS: A Markov model was used to evaluate the cost-effectiveness of three strategies for symptomatic patellar chondral lesions: 1) nonoperative management, 2) PJAC, and 3) MACI. Model inputs (transition probabilities, utilities, and costs) were derived from literature review and an institutional cohort of 67 patients treated with PJAC for patellar chondral defects (mean age 26 years, mean lesion size 2.7 cm2). Societal and payer perspectives over a 15-year time horizon were evaluated. The principal outcome measure was the incremental cost-effectiveness ratio (ICER) using a $100,000/quality-adjusted life year (QALY) willingness-to-pay threshold. Sensitivity analyses were performed to assess the robustness of the model and the relative effects of variable estimates on base case conclusions. RESULTS: From a societal perspective, nonoperative management, PJAC, and MACI cost $4,140, $52,683, and $83,073 and were associated with 5.28, 7.22, and 6.92 QALYs gained, respectively. PJAC and MACI were cost-effective relative to nonoperative management (ICERs $25,010/QALY and $48,344/QALY, respectively). PJAC dominated MACI in the base case analysis by being cheaper and more effective, but this was sensitive to the estimated effectiveness of both strategies. PJAC remained cost-effective if PJAC and MACI were considered equally effective. CONCLUSIONS: In the management of symptomatic patellar cartilage defects, PJAC and MACI were both cost-effective compared to nonoperative management. Because of the need for one surgery instead of two, and less costly graft material, PJAC was cheaper than MACI. Consequently, when PJAC and MACI were considered equally effective, PJAC was more cost-effective than MACI. Sensitivity analyses accounting for the lack of robust long-term data for PJAC or MACI demonstrated that the cost-effectiveness of PJAC versus MACI depended heavily on the relative probabilities of yielding similar clinical results. LEVEL OF EVIDENCE: III, economic and decision analysis.

Patellofemoral joint cartilage restoration with particulated juvenile allograft in patients under 21 years old.

BACKGROUND: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. PURPOSE: To report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment. METHODS: A retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society's (ICRS) standardized system. RESULTS: Thirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication. CONCLUSION: Restoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure. What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007. WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes.

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

Medial patellofemoral ligament (MPFL) reconstruction with tibial tubercle osteotomy (TTO) and particulated juvenile articular cartilage (PJAC) grafting can be performed in combination for the treatment of recurrent patellar instability with associated patellar cartilaginous defects. Description: Preoperative planning is an essential component for this procedure. Measurement of the tibial tubercle to trochlear groove (TT-TG) distance and the Caton-Deschamps index (CDI) allows for determination of the degree of medial and anterior translation and helps to identify whether distalization is necessary. The procedure begins with a thorough examination under anesthesia to determine range of motion, patellar tracking, translation, and tilt. A diagnostic arthroscopy is performed, at which time patellar tracking is again assessed and the patellar and trochlear cartilage are evaluated. A medial parapatellar incision is made, and the layer between the capsule and retinaculum is identified. This layer will serve as the location for the MPFL graft passage. The medial patella is decorticated to prepare for graft fixation. The patella is then everted, and the cartilaginous defect is prepared and sized. The PJAC graft is prepared on the back table based on these measurements. The MPFL graft is then anchored to the decorticated medial patella. Attention is then turned to performing the TTO. The patellar tendon is isolated and protected. The osteotomy shingle is created with a combination of sagittal saw and osteotomes, followed by shingle translation and fixation. Attention is then turned to performing the MPFL graft fixation on the femur. An incision is made, the area of the sulcus between the medial epicondyle and adductor tubercle is identified, and a pin is placed. Graft isometry is assessed, pin placement is confirmed, and a socket is created. After thorough irrigation, the patella is then everted and the PJAC graft is implanted and set with fibrin glue. Finally, the MPFL graft is passed through the previously identified layer and docked into the medial femur at its isometric point. Alternatives: Nonoperative treatment of first-time patellar instability can often include physical therapy, bracing, and activity modification. However, recurrence rates can be high, especially in a subset of high-risk patients with characteristics such as age of <25 years, trochlear dysplasia, patella alta, and coronal plane malalignment. For patients with recurrent patellar instability, a well-executed MPFL reconstruction restores stability while the TTO serves to unload the lateral and/or inferior patellar cartilage and correct osseous malalignment. Additional techniques, such as a distal femoral osteotomy and trochleoplasty, have been suggested to address patellar tracking and trochlear dysplasia. For patients who have sustained cartilaginous injury from their previous dislocations, PJAC can be utilized to restore the patellofemoral cartilage. Alternative operative treatments of cartilaginous defects include matrix-induced autologous chondrocyte implantation (MACI), mosaicplasty, osteochondral allograft, microfracture, and-in later stages of disease-patellofemoral arthroplasty. Rationale: The MPFL is an important medial stabilizer in the knee, with high rates of injury in patients who have experienced patellar instability. When an MPFL reconstruction is combined with a TTO, it can stabilize the patella while simultaneously correcting osseous malalignment and unloading the patellofemoral joint. Additionally, use of PJAC is advantageous for patients with patellar chondral defects because it is a single-stage technique, has low technical difficulty, and can be customized to accommodate large lesions. Expected Outcomes: MPFL in combination with TTO and PJAC provides patellar stabilization and overall improvements in pain and function, with low rates of recurrent instability. A recent study by Franciozi et al. showed significant improvement in functional outcome scores at a minimum of 2 years with no recurrent subluxations or dislocations1. Another study by Krych et al. showed an 83% rate of return to sport in patients who underwent MPFL reconstruction combined with TTO2. With respect to PJAC grafts, a study by Grawe et al. assessed the maturation of PJAC implanted into patellar chondral defects, demonstrating that the matured grafts paralleled the characteristics of the surrounding native cartilage. In addition, the authors reported that 73% of patients who completed follow-up magnetic resonance imaging at 2 years postoperatively had good defect fill, defined as >66%3. Important Tips: A lateral release may be necessary if the patella is unable to be everted parallel with the table. Typically, 80% of patients with instability do not need a lateral release, whereas 80% of patients with malalignment and isolated patellar osteoarthritis do need a release.MPFL graft isometry should be assessed by manually placing the patella in the center of the trochlea and flexing the knee to roughly 70°. The graft should slacken in subsequent deeper flexion and should never tighten.When customizing the TTO to obtain the necessary anatomic alignment, the surgeon can achieve additional medialization by dropping their hand to create a flatter cut, while additional anteriorization can be created with a steeper cut.Once the cartilage defect has been prepared and measured, a mold can be created to allow for concomitant PJAC preparation on the back table earlier in the procedure. Acronyms and Abbreviations: TT-TG = tibial tubercle to trochlear groove distanceMPFL = medial patellofemoral ligamentTTO = tibial tubercle osteotomyPJAC = particulated juvenile articular cartilageMACI = matrix-induced autologous chondrocyte implantationOR = operating roomIV = intravenousK-wires = Kirschner wiresCPM = continuous passive motionMRI = magnetic resonance imagingOA = osteoarthritisASA = acetylsalicylic acid (aspirin)DVT = deep vein thrombosisPPX = prophylaxisNWB = non-weight-bearingFWB = full weight-bearingPOD = postoperative day.

Evaluation and management of patellar instability.

Patellar instability is a common clinical problem that primarily affects the adolescent and young adult population. The demographic and anatomic risk factors that predispose patients to patellar instability are multifactorial and include young age, female sex, trochlear dysplasia, elevated tibial tubercle to trochlear groove distance (TT-TG), patella alta, femoral and tibial malalignment, ligamentous laxity, and lack of neuromuscular control. There have been substantial efforts to predict which patients who sustain a first-time dislocation will go on to incur additional dislocations. This is particularly important because with each dislocation event, there is a significant risk of injury to the patellofemoral joint including both medial patellofemoral ligament (MPFL) stretch or rupture and damage to the cartilage which can range from simple fissures to full-thickness cartilage defects and osteochondral fractures. Prediction models have demonstrated that amongst first time dislocators, young patients with trochlear dysplasia are at the highest risk for redislocation. The current standard of care for treatment of first-time dislocators without a loose body or osteochondral fracture is nonoperative management. However, recently there has been a focus on implementing a risk-stratified approach to the surgical indications for a first-time dislocator as the high-risk population might be better treated with early surgical stabilization to prevent or reduce their risk of recurrent dislocation and its associated morbidity. Likewise, for patients with recurrent dislocations, it remains to be determined whether an isolated MPFL reconstruction is sufficient for high-risk patients with several poor prognostic risk factors or if bony realignment procedures should be implemented concurrently.

Application of Machine Learning Algorithms to Predict Clinically Meaningful Improvement After Arthroscopic Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Understanding specific risk profiles for each patient and their propensity to experience clinically meaningful improvement after anterior cruciate ligament reconstruction (ACLR) is important for preoperative patient counseling and management of expectations. PURPOSE: To develop machine learning algorithms to predict achievement of the minimal clinically important difference (MCID) on the International Knee Documentation Committee (IKDC) score at a minimum 2-year follow-up after ACLR. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: An ACLR registry of patients from 27 fellowship-trained sports medicine surgeons at a large academic institution was retrospectively analyzed. Thirty-six variables were tested for predictive value. The study population was randomly partitioned into training and independent testing sets using a 70:30 split. Six machine learning algorithms (stochastic gradient boosting, random forest, neural network, support vector machine, adaptive gradient boosting, and elastic-net penalized logistic regression [ENPLR]) were trained using 10-fold cross-validation 3 times and internally validated on the independent set of patients. Algorithm performance was assessed using discrimination, calibration, Brier score, and decision-curve analysis. RESULTS: A total of 442 patients, of whom 39 (8.8%) did not achieve the MCID, were included. The 5 most predictive features of achieving the MCID were body mass index ≤27.4, grade 0 medial collateral ligament examination (compared with other grades), intratunnel femoral tunnel fixation (compared with suspensory), no history of previous contralateral knee surgery, and achieving full knee extension preoperatively. The ENPLR algorithm had the best relative performance (C-statistic, 0.82; calibration intercept, 0.10; calibration slope, 1.15; Brier score, 0.068), demonstrating excellent predictive ability in the study's data set. CONCLUSION: Machine learning, specifically the ENPLR algorithm, demonstrated good performance for predicting a patient's propensity to achieve the MCID for the IKDC score after ACLR based on preoperative and intraoperative factors. The femoral tunnel fixation method was the only significant intraoperative variable. Range of motion and medial collateral ligament integrity were found to be important physical examination parameters. Increased body mass index and prior contralateral surgery were also significantly predictive of outcome.

Return to Sport After Bone-Patellar Tendon-Bone Autograft ACL Reconstruction in High School-Aged Athletes.

BACKGROUND: Anterior cruciate ligament (ACL) injuries are occurring with increasing frequency in the adolescent population. Outcomes after ACL reconstruction (ACLR) are inconsistently reported in homogeneous patient populations. PURPOSE/HYPOTHESIS: To evaluate outcomes after bone-patellar tendon-bone (BTB) autograft ACLR in competitive high school-aged athletes by examining return to sport (RTS), patient satisfaction, and reinjury rates. Our hypothesis was that RTS rates and satisfaction will be high and reinjury rates will be low. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: An institutional ACL registry was utilized to identify competitive high school-aged athletes (14-18 years old) who underwent primary ACLR using BTB autograft with a minimum 2-year follow-up. A postoperative questionnaire was administered to determine rates and types of RTS, quality of sports performance, reinjury, and satisfaction. Uni- and multivariable analyses were used to identify demographic, sport-specific, and clinical factors related to RTS. RESULTS: A total of 53 patients were included (mean ± SD age at the time of surgery, 16.6 ± 1.34 years). Mean follow-up was 3.78 ± 0.70 years (range, 2.60-4.94 years). The overall ipsilateral ACL retear rate was 7.5% (n = 4). There were 10 subsequent ACL tears to the contralateral knee (19%). Forty-four (83%) patients successfully returned to at least their prior level of sport at a mean 10.5 ± 8.7 months (range, 3-48 months). Overall satisfaction was high, with 91% of patients very satisfied with the outcome. Higher confidence levels regarding performance of the reconstructed knee were associated with increased probability of RTS on multivariate analysis. CONCLUSION: BTB autograft ACLR results in high rates of RTS and satisfaction and low rates of subsequent ipsilateral ACL injuries in competitive high school-aged athletes. Patients with higher confidence in performance of the reconstructed knee are more likely to return to at least their prior level of sport.

Reliability of Radiologic Assessments of Clinically Relevant Growth Remaining in Knee MRI of Children and Adolescents With Patellofemoral Instability: Data From the JUPITER Cohort.

BACKGROUND: Surgical decision making and preoperative planning for children and adolescents with patellofemoral instability rely heavily on a patient's skeletal maturity. To be clinically useful, radiologic assessments of skeletal maturity must demonstrate acceptable interrater reliability and accuracy. PURPOSE: The purpose of this study was to examine the interrater reliability among surgeons of varying experience levels and specialty training backgrounds when evaluating the skeletal maturity of the distal femur and proximal tibia of children and adolescents with patellofemoral instability. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: Six fellowship-trained orthopaedic surgeons (3 pediatric orthopaedic, 2 sports medicine, and 1 with both) who perform a high volume of patellofemoral instability surgery examined 20 blinded knee radiographs and magnetic resonance images in random order. They assessed these images for clinically relevant growth (open physis) or clinically insignificant growth (closing/closed physis) remaining in the distal femoral and proximal tibial physes. Fleiss' kappa was calculated for each measurement. After initial ratings, raters discussed consensus methods to improve reliability and assessed the images again to determine if training and new criteria improved interrater reliability. RESULTS: Reliability for initial assessments of distal femoral and proximal tibial physeal patency was poor (kappa range, 0.01-0.58). After consensus building, all assessments demonstrated almost-perfect interrater reliability (kappa, 0.99 for all measurements). CONCLUSION: Surgical decision making and preoperative planning for children and adolescents with patellofemoral instability rely heavily on radiologic assessment of skeletal maturity. This study found that initial interrater reliability of physeal patency and clinical decision making was unacceptably low. However, with the addition of new criteria, a consensus-building process, and training, these variables became highly reliable.

Development of a Multivariable Model Based on Individual Risk Factors for Recurrent Lateral Patellar Dislocation.

BACKGROUND: Nonoperative treatment after first-time patellar dislocation is the standard of care. There is evidence that certain patients may be at high risk for recurrent instability. The aim of this study was to develop a multivariable model to guide management of patients based on their individual risk of recurrent dislocation. METHODS: A multivariable model was developed using 291 patients from 4 institutions to identify which patients were at higher risk for recurrent patellar dislocation within 2 years. This model was informed by a univariable logistic regression model developed to test factors based on the patient's history, physical examination, and imaging. The discriminatory ability of the model to classify who will or will not have a recurrent dislocation was measured using the area under the receiver operating characteristic curve (AUC). RESULTS: Age, a history of a contralateral patellar dislocation, skeletal immaturity, lateral patellar tilt, tibial tubercle-trochlear groove (TT-TG) distance, Insall-Salvati ratio, and trochlear dysplasia were the most important factors for recurrent patellar dislocation. Sex, mechanism of injury, Caton-Deschamps ratio, sulcus angle, inclination angle, and facet ratio were not factors for recurrent dislocation. The overall AUC for the multivariable model was 71% (95% confidence interval [CI]: 64.7% to 76.6%). CONCLUSIONS: Optimizing the management of lateral patellar dislocation will improve short-term disability from the dislocation and reduce the long-term risk of patellofemoral arthritis from repeated chondral injury. This multivariable model can identify patients who are at high risk for recurrent dislocation and would be good candidates for early operative treatment. Further validation of this model in a prospective cohort of patients will inform whether it can be used to determine the optimal treatment plan for patients presenting with an initial patellar dislocation. Until validation of the model is done with new patients, it should not be used in clinical practice. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Assessment and Trends of the Methodological Quality of the Top 50 Most Cited Articles on Patellar Instability.

BACKGROUND: Studies with a low level of evidence (LOE) have dominated the top cited research in many areas of orthopaedics. The wide range of treatment options for patellar instability necessitates an investigation to determine the types of studies that drive clinical practice. PURPOSE: To determine (1) the top 50 most cited articles on patellar instability and (2) the correlation between the number of citations and LOE or methodological quality. STUDY DESIGN: Cross-sectional study. METHODS: The Scopus and Web of Science databases were assessed to determine the top 50 most cited articles on patellar instability between 1985 and 2019. Bibliographic information, number of citations, and LOE were collected. Methodological quality was calculated using the Modified Coleman Methodology Score (MCMS) and the Methodological Index for Non-Randomized Studies (MINORS). Mean citations and mean citation density (citations per year) were correlated with LOE, MCMS, and MINORS scores. RESULTS: Most studies were cadaveric (n = 10; 20.0%), published in the American Journal of Sports Medicine (n = 13; 26.0%), published between 2000 and 2009 (n = 41; 82.0%), and conducted in the United States (n = 17; 34.0%). The mean number of citations and the citation density were 158.61 ± 59.53 (range, 95.5-400.5) and 12.74 ± 5.12, respectively. The mean MCMS and MINORS scores were 59.62 ± 12.58 and 16.24 ± 3.72, respectively. No correlation was seen between mean number of citations or citation density versus LOE. A significant difference was found in the mean LOE of articles published between 1990 and 1999 (5.0 ± 0) versus those published between 2000 and 2009 (3.12 ± 1.38; P = .03) and between 2010 and 2019 (3.00 ± 1.10; P = .01). CONCLUSION: There was a shift in research from anatomy toward outcomes in patellar instability; however, these articles demonstrated low LOE and methodological quality. Higher quality studies are necessary to establish informed standards of management of patellar instability.

Return to Work Following Tibial Tubercle Osteotomy for Patellofemoral Osteoarthritis and Pain.

PURPOSE: To evaluate the ability of patients to return to work following anteromedialization (AMZ) tibial tubercle osteotomy (TTO) due to isolated patellofemoral osteoarthritis or pain. METHODS: Consecutive patients undergoing AMZ TTO were reviewed retrospectively at a minimum of 1 year postoperatively. Patients completed a subjective work questionnaire, a visual analog scale for pain, as well as a Kujala questionnaire and satisfaction questionnaire. RESULTS: Fifty-seven patients (61 knees; average age: 32.7 ± 9.6 years) were contacted at an average follow-up of 4.86 ± 2.84 years postoperatively. The preoperative Kujala score improved from 55.7 ± 17.8 to 84.6 ± 15.8 at final follow-up (P < 0.001). Thirty-seven patients (64.9%) were employed within 3 years prior to surgery and 34 patients (91.9%) were able to return to work by 2.8 ± 2.6 months postoperatively. However, only 27 patients (73.0%) of patients were able to return to the same level of occupational intensity. Patients who held sedentary, light-, medium-, or high-intensity occupations were able to return to work at a rate of 100.0%, 93.8%, 77.8%, and 100.0% by 2.2 months, 3.0 months, 3.1 months, and 4.0 months, postoperatively. No patients underwent revision TTO or conversion to arthroplasty by the time of final follow-up. CONCLUSION: In patients with focal patellofemoral osteoarthritis or pain, AMZ TTO provides a high rate of return to work (91.9%) by 2.8 ± 2.6 months postoperatively. Patients with higher intensity occupations may take longer to return to work than those with less physically demanding occupations. LEVEL OF EVIDENCE: III.

Comparison of Ligament Isometry and Patellofemoral Contact Pressures for Medial Patellofemoral Ligament Reconstruction Techniques in Skeletally Immature Patients.

BACKGROUND: Adult medial patellofemoral ligament (MPFL) reconstruction techniques are not appropriate for the skeletally immature patient given the proximity of the distal femoral physis. Biomechanical consequences of reconstructions aimed at avoiding the physis have not been adequately studied. PURPOSE: To quantify the biomechanical effects of MPFL reconstruction techniques intended for skeletally immature patients. STUDY DESIGN: Controlled laboratory study. METHODS: Four MPFL reconstruction techniques were evaluated using a computationally augmented cadaveric model: (1) Schoettle point: adult-type reconstruction; (2) epiphyseal: socket distal to the femoral physis; (3) adductor sling: graft wrapped around the adductor tendon; (4) adductor transfer: adductor tendon transferred to patella. A custom testing frame was used to cycle 8 knees for each technique from 10° to 110° of flexion. Patellofemoral kinematics were recorded using a motion camera system, contact stresses were recorded using Tekscan pressure sensors, and MPFL length was computed using an inverse kinematics computational model. Change in MPFL length, patellar facet forces, and patellar kinematics were compared using generalized estimating equation modeling. RESULTS: Schoettle point reconstruction was the most isometric, demonstrating isometry from 10° to 100°. The epiphyseal technique was isometric until 60°, after which the graft loosened with increasing flexion. The adductor sling and adductor transfer techniques were significantly more anisometric from 40° to 110°. Both grafts tightened with knee flexion and resulted in significantly more lateral patellar tilt versus the intact state in early flexion and significantly higher contact forces on the medial facet versus the epiphyseal technique in late flexion. CONCLUSION: In this cadaveric simulation, the epiphyseal technique allowed for a more isometric ligament until midflexion, when the patella engaged within the trochlear groove. The adductor sling and adductor transfer grafts became tighter in flexion, resulting in potential loss of motion, pain, graft stretching, and failure. Marginal between-condition differences in patellofemoral contact mechanics and patellar kinematics were observed in late flexion. CLINICAL RELEVANCE: In the skeletally immature patient, using an epiphyseal type MPFL reconstruction with the femoral attachment site distal to the physis results in a more isometric graft compared with techniques with attachment sites proximal to the physis.

Opioid Consumption After Arthroscopic Meniscal Procedures and Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Procedure-specific opioid-prescribing guidelines have the potential to decrease the number of unused pills in the home without compromising patient satisfaction. However, there is a paucity of data on the minimum necessary quantity to prescribe for outpatient orthopaedic surgeries. PURPOSE: To prospectively record daily opioid use and pain levels after arthroscopic meniscal procedures and anterior cruciate ligament reconstruction (ACLR) at a single institution. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 95 adult patients who underwent primary arthroscopic knee surgery (meniscectomy, repair, or ACLR) were enrolled. Patients with a history of opioid dependence were ineligible. Daily opioid consumption and Numeric Rating Scale pain scores were collected through an automated text-messaging platform starting on postoperative day 1 (POD1). At 6 weeks or at patient-reported cessation of opioid use, final survey questions were asked. Patients who failed to complete data collection were excluded. Opioid use was converted into "pills" (oxycodone 5-mg equivalents) to facilitate comparisons and clinical applications. Factors associated with high and low opioid use were compared. RESULTS: Of the 95 patients enrolled, 71 (74.7%) were included in the final analysis. Of these, 40 (56.3%) underwent meniscal surgery and 31 (43.7%) underwent ACLR. After outpatient arthroscopic meniscectomy or repair, the total median postdischarge opioid use was 0.3 pills (oxycodone 5-mg equivalents), with 75% of patients consuming 3.3 or fewer pills (range, 0-19 pills). For ACLR, the median postdischarge consumption was 7 pills (75th percentile, 23.3 pills; range, 0-41 pills). Almost one-third of patients (32.3%) took no opioids after surgery (3 ACLR, 20 meniscus). All meniscus patients and 71% of ACLR patients ceased opioid consumption by postoperative day 7. CONCLUSION: Opioids may not be necessary in all patients, particularly after meniscal surgery and in comparison with ACLR. For patients requesting opioids for pain relief, reasonable prescription quantities are 5 oxycodone 5-mg pills after arthroscopic meniscal procedures and 20 5-mg pills after ACLR. Slowing the current opioid epidemic and preventing future crises is dependent on refining prescribing habits. Clinicians should strongly consider patient education regarding expected pain as well as pain management strategies.

Medial Patellofemoral Ligament Isometry in the Setting of Patella Alta.

PURPOSE: To investigate alterations in technique for medial patellofemoral ligament (MPFL) reconstruction in the setting of patella alta and describe the effect of these alterations on MPFL anatomometry. METHODS: Ten cadaveric knees were used. Four candidate femoral attachment sites of MPFL were tested. The attachment sites were Schottle's point (SP), 5 mm distal to SP, 5 mm proximal to SP, and 10 mm proximal to SP. A suture anchor was placed at the upper 40% of the medial border of the patella with the emanating suture used to simulate the reconstructed ligament. MPFL maximum length change was calculated through a range of motion between 0° and 110°. Recordings at all 4 candidate femoral attachments sites were repeated after a flat tibial tubercle osteotomy and transfer to achieve alta as measured by the Caton-Deschamps Index (CDI) of 1.3, 1.4, and 1.5. RESULTS: The 10 specimens had an average CDI of 0.99, range 0.87 to 1.16. In the native tibial tubercle condition, SP was more isometric through 20° to 70° range of motion, or anatomometric, than any other candidate femoral attachment location. With patella alta with a CDI of 1.3 and 1.4, attachment site 5 mm proximal to SP exhibited more anatomometry than SP. With patella alta with a CDI of 1.5, attachment site 10 mm proximal to SP exhibited more anatomometry than SP. CONCLUSIONS: Increased patella alta significantly alters MPFL anatomometry. With increasing degrees of patella alta, more proximal candidate femoral attachment sites demonstrate decreased change in length compared with SP. None of the varied femoral attachments produced anatomometry over the entirety of the flexion range from 20° to 70°, suggesting that in cases of significant patella alta, proximalization the femoral attachment site of MPFL reconstruction may be necessary to achieve an anatomometric MPFL reconstruction. CLINICAL RELEVANCE: A standardized, isolated MPFL reconstruction may be prone to failure in the setting of patella alta, given the anisometry demonstrated. Alternative femoral attachment sites for MPFL reconstruction should be considered in these patients.