Yanke, Adam B.

Background: Distal femoral osteotomy (DFO) may be performed via either a lateral opening-wedge (LOW) or medial closing-wedge (MCW) osteotomy with meaningful clinical improvements; however, the effects of each DFO technique on leg length have not been well characterized. Purpose: To (1) validate a radiographic measurement technique to predict leg length changes after DFO and (2) compare the change in leg length after DFO for the LOW and MCW techniques. Study Design: Cohort study; Level of evidence, 3. Methods: Preoperative and postoperative full-length standing radiographs obtained from patients who underwent DFO at 1 of 2 academic medical centers were evaluated. The region on the medial (for LOW) or lateral (for MCW) distal femur cortex that would be the “hinge point” during DFO was identified on the radiographs. The distance from the center of the femoral head to the hinge point ( A ), the distance from the hinge point to the center of the talus ( B ), and the resultant angle (α) were measured. The equation presented within the text was used to plot the predicted leg length changes corresponding to the change in alpha angle produced by DFO. Comparisons were made between (1) the predicted and measured leg length changes after DFO and (2) the measured leg length change after LOW versus MCW osteotomies. Results: For both LOW (n = 10) and MCW (n = 10) osteotomies, the predicted leg length change was equivalent to the true change measured on postoperative radiographs (LOW: P = .16; MCW: P = .85). There was a mean lengthening of 0.85 mm (range, 0.5-1.3 mm) for every 1° of mechanical axis correction with LOW DFO, compared to a mean shortening of 0.45 mm (range, 0.1-1.4 mm) per 1° of MCW correction. Conclusion: Preoperative radiographic imaging can be used to predict leg length change after DFO with high reliability. Surgeons can expect approximately 0.85 mm of lengthening per 1° of DFO correction when performing LOW osteotomies, compared to 0.45 mm of shortening per 1° of correction for MCW osteotomies. However, the most accurate prediction results from patient-specific calculations.

Background: Outcomes after arthroscopic rotator cuff repair (RCR) are frequently measured through clinically significant outcomes (CSOs) such as the minimal clinically important difference, the substantial clinical benefit, and the Patient Acceptable Symptom State. Global achievement of CSOs is challenging to predict. Purpose: To determine if unsupervised machine learning can identify distinct patient subgroups based on CSO achievement after elective arthroscopic RCR. Study Design: Case-control study; Level of evidence, 3. Methods: A prospectively collected database was analyzed to identify patients who underwent elective arthroscopic RCR from 2015 to 2017. Tear dimensions were measured on magnetic resonance imaging utilizing a validated technique. CSO achievements on the American Shoulder and Elbow Surgeons, the Single Assessment Numeric Evaluation, and the Constant-Murley subjective score at 2-year follow-up were calculated. An unsupervised random forest algorithm was utilized to develop and internally validate patient subgroups with significantly different rates of CSO achievement. Patient subgroup membership, along with a total of 30 demographic and clinical variables, as well as preoperative patient-reported outcomes, were incorporated into a stepwise multivariable logistic regression to identify factors predictive of optimal CSO achievement. Results: A total of 346 patients (192 male; mean ± SD age, 57.2 ± 9.1 years; body mass index, 30.1 ± 5.4 kg/m 2 ) were eligible for inclusion and followed for a mean of 3.8 years (range, 2.0-6.2 years) Of these, a total of 333 patients were partitioned by the random forest algorithm into 2 subgroups (stability, 0.16; connectivity: 180.8; Dunn: 0.16; silhouette: 0.05), with 176 patients in the optimal achievement subgroup and 157 patients in the suboptimal achievement subgroup. The 2 subgroups differed significantly (all P ≤ .004) in the likelihood of achievement of all CSOs. Stepwise multivariable logistic regression identified an increase of 1 mm in tear size in the sagittal dimension beyond 1.9 cm to predict a 10% increase in the probability of suboptimal achievement. Additional risk factors for suboptimal CSO achievement included increasing number of tendons involved (odds ratio [OR], 14.07; 95% CI, 4.50-44.02; P < .001), subscapularis involvement (OR, 8.67; 95% CI, 2.45-30.71; P = .01), and increased preoperative CMS score (OR, 1.11; 95% CI, 1.04-1.18; P = .001). Protective factors included performance of a subpectoral biceps tenodesis compared with biceps tenotomy (OR, 0.22; 95% CI, 0.05-0.92; P = .03). Conclusion: Clinically meaningful subgroups were uncovered using an unsupervised machine learning algorithm in patients undergoing arthroscopic RCR. Tear size, number of tendons involved, and subscapularis involvement were significant and additive predictors of suboptimal CSO achievement at 2-year minimum follow-up. Treatment of concurrent biceps pathology with tenodesis conferred 78% increased likelihood of CSO achievement compared with tenotomy.

Background: Despite mounting clinical evidence for the utility of orthobiologics in nonoperative management of orthopaedic pathology, the market for orthobiologic therapies remains largely unregulated by the Food and Drug Administration, giving rise to a wide range of pricing for these therapeutics by different provider types. Purpose: To determine the availability and pricing for platelet-rich plasma (PRP), amniotic or adipose “stem cell,” and bone marrow aspirate concentrate (BMC) injections for the treatment of knee osteoarthritis among orthopaedic sports medicine and alternative providers (eg, chiropractic clinics and stand-alone “regenerative medicine” clinics) in a major metropolitan city. Study Design: Cross-sectional study. Methods: Orthopaedic sports medicine providers in the Chicagoland area were identified through the American Orthopaedic Society for Sports Medicine (AOSSM) and Arthroscopy Association of North America (AANA) surgeon databases. Alternative clinics offering orthobiologic injections were systematically compiled using Yelp! and Google search listings and reviews. Clinics were contacted using a standardized telephone script. Data were collected for each site on the types of injections offered, whether price was disclosed over the telephone, the price of injections offered, and the source of stem cell injections if they were provided. Mann-Whitney U tests were used to compare the mean price between practices. F tests for equality of variances were used to compare the variability in prices between practice types. Results: A total of 25 unique orthopaedic sports medicine practices (comprising 80 AOSSM/AANA surgeons) and 40 alternative clinics offered PRP, stem cell, and/or BMC injections, as indicated over the telephone. There was no difference in likelihood of offering PRP ( P = .698) or BMC injections ( P = .340). However, alternative clinics were significantly more likely to offer stem cell injections ( P < .001). There was no difference in the willingness to disclose the price for PRP ( P = .269), stem cell injections ( P = .302), and BMC ( P = .528) or the source of what each clinic advertised as stem cell injections ( P = .630). The mean price for a single PRP injection was significantly higher ( P = .011) and significantly more variable ( F statistic = .139; P < .001) at alternative clinics. Similarly, the mean price for a single stem cell injection was significantly higher ( P < .001) and significantly more variable ( F statistic = 0.080; P = .025) at alternative clinics. Conclusion: This study demonstrates that orthobiologic knee injections are highly prevalent for in-clinic use within the Chicago metropolitan area, with PRP being the most commonly used therapeutic. When compared with orthopaedic sports medicine providers, alternative clinics were more likely to offer stem cell injections and charge a significantly greater and more variable amount per PRP and stem cell treatment.

Purpose To perform a prospective, double‐blind, randomized controlled trial to assess differences in integration and patient‐reported outcomes metrics (PROMs) of osteochondral allograft transplantation with and without bone marrow aspirate concentrate (BMAC) augmentation. Methods Patients (n = 36) undergoing osteochondral allograft transplantation of the knee were consented and enrolled in this prospective study. They were randomized to either iliac crest BMAC or sham incision groups and blinded to their allocation. Computerized tomography (CT) scans of the knee were obtained at 6 months postoperatively after the index transplantation and graded by the semiquantitative assessment CT osteochondral allograft system. PROMs, including the International Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score–Joint Replacement, were obtained at 6 months, 1 year, and 2 years postoperatively. Results On 6‐month postoperative CT scans, patients receiving BMAC‐treated grafts were more likely to have small cystic changes ( P = .01), with an associated trend toward reduction in large cyst formation ( P = .06), but equal osseous integration, graft signal density, and presence of discernible clefts and intra‐articular fragments. The BMAC group was less likely to undergo subsequent surgery for graft debridement or revision (5.3% vs 35.3%; P = .02). There were no significant differences in PROMs between the 2 groups preoperatively or postoperatively at 6 months, 1 year, or 2 years. Patients receiving BMAC trended toward a higher rate of achievement of Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score–Joint Replacement minimal clinically important difference (88% vs 55%; P = .076). Conclusions Patients receiving BMAC‐treated grafts were more likely to have small cystic changes and were less likely to undergo subsequent surgery for persistent or new symptoms after the index procedure. No difference in postoperative PROMs was shown at the 6‐month, 1‐year, and 2‐year follow‐ups between the 2 groups. Level of Evidence Level I, prospective, randomized controlled trial.

Background: Various medial patellofemoral ligament (MPFL) reconstruction techniques have been developed to minimize risks to the physis in skeletally immature patients. Purpose: To examine outcomes of MPFL reconstruction (MPFLR) based on fixation technique in skeletally immature patients. Study Design: Systematic review; Level of evidence, 4. Methods: PubMed, Scopus, Ovid, Cochrane Library, and CINAHL databases were searched for the literature on outcomes of MPFLR in the pediatric population, utilizing various anatomic and nonanatomic techniques. Primary outcomes were postoperative redislocation rates, return-to-sports (RTS) rates, and patient-reported outcomes (PROs). Moreover, outcomes involving sequela of growth plate disturbance were collected. Results: The final analysis included 17 studies—2 using sling-based techniques, 3 using surface-based techniques, 5 using soft tissue realignments, and 7 utilizing transosseous femoral fixations. Higher rates of postoperative redislocation were found in the sling-based (14.8%) and distal soft tissue realignment using semitendinosus tenodesis (38%) techniques, while lower rates were noted with surface-based (1.3%) and transosseous (3.4%) techniques. For PROs, there were large amounts of heterogeneity among studies, but all reported postoperative improvements, with more positive PROs generally seen in anatomic reconstructions. The RTS rate was 100% for surface-based techniques, 79.4% for distal soft tissue realignments, 79.5% for soft tissue realignment techniques, and 83.2% for transosseous techniques. No negative outcomes as a sequela of growth plate disturbance were reported. Conclusion: Nonanatomic techniques—such as sling-based and distal soft tissue realignment techniques—have higher rates of redislocation and lower RTS rates in skeletally immature patients undergoing MPFLR. Surface-based and transosseous tunnel-based techniques were shown to have lower redislocation and higher RTS rates. Clinical Relevance: This review provides insight into the most appropriate surgical management of patellar instability in patients with open growth plates.

Background: Medial patellofemoral ligament reconstruction is frequently indicated for recurrent lateral patellar instability. The preoperative presence and severity of a J-sign have been associated with poorer postoperative outcomes. Purpose: To determine the underlying anatomic factors that contribute to the presence, severity, and jumping quality of the J-sign. Study Design: Cross-sectional study; Level of evidence, 3. Methods: All patients undergoing evaluation for patellar instability at a single institution between 2013 and 2023 and healthy controls without patellar instability were included. Patients with a history of knee osteotomies were excluded. The presence of a jumping J-sign and its relationship to patellofemoral measures including the Caton-Deschamps Index (CDI), trochlear dysplasia (Dejour grade), tibial tubercle–trochlear groove (TT-TG) distance, tibial tubercle lateralization, trochlear bump height, mechanical alignment, femoral anteversion, tibial torsion, trochlear medialization, patellar width, axial patellar/trochlear overlap, patellar height, trochlear height, and knee rotation angle (KRA) were measured using standardized 1.5-T magnetic resonance imaging (MRI). Univariate pairwise and multivariable analyses were performed to determine the factors associated with J-sign presence, severity, and quality. Results: Of the 130 knees with patellar instability, 89 (68.5%) demonstrated a J-sign on physical examination. In total, 44 (33.8%) patients demonstrated a 1-quadrant J-sign, 32 (24.6%) demonstrated a 2-quadrant smooth J-sign, and 13 (10.0%) demonstrated a jumping J-sign. A total of 22 control, noninstability cases were included. On multivariable analysis, increasing TT-TG distance (OR, 1.1 increase per millimeter; P = .04), external KRA (OR, 1.1 increase per degree; P = .02), and increasing CDI (OR, 1.3 increase per 0.1 increase in CDI; P = .02) were associated with J-sign presence. Increasing bump height (OR, 1.72 increase per millimeter; P = .007) and decreasing patellar width (OR, 0.89 decrease per millimeter; P = .076) were associated with a larger J-sign, when present. Increasing bump height (OR, 1.80 increase per millimeter; P = .018), increasing patellar width (OR, 1.33 increase per millimeter; P = .047), and decreasing CDI (OR, 0.009 decrease per 0.01 increase in ratio; P = .008) were associated with a jumping J-sign in comparison with a smooth 2-quadrant J-sign. A KRA of 10° (AUC, 0.70) and a cartilaginous bump height of 6.6 mm (AUC, 0.73) were thresholds associated with jumping J-sign presence. Conclusion: The presence of a J-sign is associated with MRI findings of relatively greater external tibiofemoral rotation, increased TT-TG distance, and increased patellar height, while J-sign severity and jumping quality are associated with the presence of additional underlying trochlear factors such as increased bump height. The anatomic drivers identified in this study should be further evaluated as possible factors associated with suboptimal outcomes after surgical management.

Background: Medial patellofemoral ligament reconstruction (MPFLR) is an excellent surgical option for patients with recurrent patellar instability. This technique has demonstrated significant improvements in patient-reported outcomes, high rates of return to sport, and low rates of failure. However, there is debate regarding the use of isolated MPFLR in the setting of concomitant pathoanatomic features such as patella alta, trochlear dysplasia, or a lateralized tibial tubercle. Purpose: To estimate the overall relative effect sizes as well as strength of evidence supporting described risk factors for recurrent instability after isolated MPFLR. Study Design: Systematic review and meta-analysis. Methods: A systematic review was performed in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed, Embase, Cochrane, and Ovid/MEDLINE databases were queried. Clinical studies for outcomes of isolated MPFLR reporting recurrent instability and associated risk factors were included. Data for each risk factor analyzed by at least 2 studies were extracted, and the heterogeneity of studies was determined by I 2 value. For variables evaluated in studies determined to have fair homogeneity, defined as I 2 <25%, DerSimonian-Laird random-effects models were generated and effect sizes were represented as mean differences or odds ratios. Results: Nine studies examining risk for recurrent instability after isolated MPFLR were identified, with 5 overlapping risk factors with low heterogeneity between studies: age, sex, tibial tubercle to trochlear groove (TT-TG) distance, Caton-Deschamps Index (CDI), and trochlear dysplasia. There was strong evidence to support the risk of recurrent instability associated with CDI >1.3 (OR, 2.72; P = .02) and dysplasia with a trochlear bump (DeJour type B or D; OR, 3.28; P <.001). Age, sex, and TT-TG distance did not cause an increased risk of recurrent instability with currently available aggregate data. Conclusion: There are signs of increased risk of failure of isolated MPFLR in the setting of DeJour type B and D trochlear dysplasia and patella alta (CDI, >1.3). Currently available data suggest that age, sex, and TT-TG distance do not cause a higher risk of recurrence for patients undergoing isolated MPFLR.

Background: Mismatch between osteochondral allograft (OCA) donor and recipient sex has been shown to negatively affect outcomes. This study accounts for additional donor variables and clinically relevant outcomes. Purpose: To evaluate whether donor sex, age, donor-recipient sex mismatch, and duration of graft storage affect clinical outcomes and failure rates after knee OCA transplantation. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing knee OCA transplantation between 2003 and 2018 were prospectively followed. Inclusion criteria consisted of primary OCA transplantation and minimum 2-year follow-up. Patient descriptive data and allograft donor sex, age, and graft storage time before implantation were collected. Patients were evaluated for reoperation, failure, and achievement of clinically significant outcomes for International Knee Documentation Committee scores. Reoperation was defined as subsequent surgical intervention of the transplanted allograft, including second-look arthroscopy for graft evaluation, debridement, and loose body removal. Failure was defined as revision of the primary OCA transplantation or conversion to arthroplasty. A Kaplan-Meier curve determined cumulative survivability of OCA transplantations, and log-rank testing was used to compare survivorship between groups. Stepwise regression analysis was utilized to evaluate associations between donor variables and achievement of clinically significant outcomes, reoperation, and failure. Results: A total of 372 patients undergoing OCA transplantation were included and followed for a mean 5.4 years (SD, 2.7; range, 2.0-16.3). Isolated OCA transplantation was performed in 45% of cases (169/372). A mismatch in donor and recipient sex was present for more female patients (90%) than male patients (10%; P < .001). Those who had a sex-mismatched graft more frequently underwent concomitant tibial tubercle osteotomy ( P = .034). When controlling for patient sex, no other differences were seen between groups matched and mismatched by sex. Univariable and multivariable analysis found no significant difference in survival free from reoperation or failure on the basis of donor-recipient sex mismatch, donor age, or graft storage time before implantation. Conclusion: In contrast to previous historical data, no donor variables were associated with inferior clinical outcomes in patients who underwent OCA transplantation. These data can help inform graft selection, expedient recipient selection, and outcome optimization after OCA transplantation.

Purpose To assess the relation between tendon migration, as measured by radiostereometric analysis, and patient‐reported outcome measures (PROMs) after biceps tenodesis (BT); to determine the likelihood of achieving clinically significant outcomes (CSOs) after BT; and to identify factors that impact CSO achievement. Methods Patients undergoing arthroscopic suprapectoral or open subpectoral BT at a single, high‐volume academic medical center were prospectively enrolled. A tantalum bead sutured to the tenodesis construct was used as a radiopaque marker. Biceps tendon migration was measured on calibrated radiographs at 12 weeks postoperatively. PROMs (Constant‐Murley, Single Assessment Numeric Evaluation [SANE], and Patient‐Reported Outcomes Measurement Information System–Upper Extremity [PROMIS‐UE] scores) were collected preoperatively and at minimum 2‐year follow‐up. Results Of 115 patients enrolled, 94 (82%) were included (median age, 52 years; median body mass index, 31.4). At a mean follow‐up of 2.9 years, the median Constant‐Murley, SANE, and PROMIS‐UE scores were 33 (interquartile range [IQR], 26‐35), 90 (IQR, 80‐99), and 47 (IQR, 42‐58), respectively. Median tantalum bead migration was 6.5 mm (IQR, 1.8‐13.8 mm). There were significant correlations between migration and Constant‐Murley score ( r 2 = 0.222; β = –0.554 [95% confidence interval (CI), –1.027 to –0.081]; P = .022), SANE score ( r 2 = 0.238; β = –0.198 [95% CI, –0.337 to –0.058]; P = .006), and PROMIS‐UE score ( r 2 = 0.233; β = –0.406 [95% CI, –0.707 to –0.104]; P = .009). On univariable analysis, higher body mass index was associated with achievement of substantial clinical benefit (unadjusted odds ratio [OR], 1.078 [95% CI, 1.007 to 1.161]; P = .038). Greater bead migration was negatively associated with achievement of the minimal clinically important difference (unadjusted OR, 0.969 [95% CI, 0.943 to 0.993]; P = .014) and patient acceptable symptomatic state (unadjusted OR, 0.965 [95% CI, 0.937 to 0.989]; P = .008) on all 3 instruments. Conclusions A 1‐cm increase in post‐tenodesis biceps tendon migration was associated with a decrease in the Constant‐Murley, SANE, and PROMIS‐UE scores of 6, 2, and 4 points, respectively, at a mean of 2.9 years after surgery. Most patients achieved CSOs for these PROMs by latest follow‐up, and greater biceps tendon construct migration was negatively associated with the likelihood of CSO achievement. Level of Evidence Level IV, retrospective case series.

Objectives: A DFO can be performed via two techniques: a lateral opening wedge (LOW) osteotomy and a medial closing wedge (MCW) osteotomy. Small case series have looked at how leg length is affected by a lateral opening wedge DFO, however, there is a lack of research comparing these leg length changes to medial closing DFO. Additionally, no studies have presented a model for predicting the leg length changes that will occur following DFO of either technique. Given that limb length differences can lead to accelerated osteoarthritis, back pain, hip pain, and other issues, being able to predict which technique can help prevent this pathology without a secondary procedure would be an important finding. Finally, the medial closing wedge osteotomy can allow for immediate weight-bearing while the lateral opening wedge does not and typically has associated cost with bone grafting. Therefore, we designed this study to validate a tool designed to predict leg length changes after distal femoral osteotomy (DFO) and compare changes following medial closing wedge (MCW) and lateral opening wedge (LOW) techniques. Methods: A collaborative retrospective review was performed of patients from Rush and Mayo Clinic databases who received a DFO and had full-length standing radiographs both pre-and postoperatively. For each preoperative radiograph, the region on the medial (for LOW) or lateral (for MCW) distal femur cortex that would be the “hinge point” during DFO was identified. The distances from the center of the femoral head to the hinge point (“A”), from the hinge point to the center of the tibial plafond (“B”), and the resultant angle at the hinge point (“α”) were measured (Figure 1). Figure 2 demonstrates the equation used to plot a graph of the predicted leg length changes corresponding to the change in α angle produced by DFO. Final leg length was calculated on postoperative radiographs, and the difference between predicted and true leg length changes was compared using paired Wilcoxon signed rank exact tests. Results: 10 MCW and 10 LOW patients were included. For both LOW (n=10) and MCW (n=10) osteotomies, the predicted leg length change was equivalent to the true change measured on postoperative radiographs (LOW P=0.16; MCW P=0.85). LOW DFO’s had 5.10 ± 2.77 mm (range: 1.45-10.87 mm) of leg lengthening, compared to 2.61 ± 1.25 mm (range: 0.50-4.56 mm) of leg shortening (p<0.001) for MCW (Figure 3). On average, there was 0.85 mm of lengthening (range 0.5-1.3 mm) for every 1° of mechanical axis correction with LOW DFO, compared to 0.45 mm of shortening (range: 0.1-1.4 mm) per 1° of MCW correction. Conclusions: This study presents a tool to accurately and reliably predict the leg length changes seen after both medial closing and lateral opening wedge DFO’s. Knowing what leg length changes to expect with each DFO technique is a useful tool that surgeons can utilize during surgical planning. Preoperative radiographic imaging can be used to predict leg length change following DFO with high reliability and accuracy. Surgeons can expect approximately 0.85mm of lengthening per 1° of DFO correction when performing LOW, compared to 0.45mm of shortening per 1° correction for MCW osteotomies.