Braig, Zachary V.

Abstract As the prevalence of hip arthroscopy increases, hip capsular defects are increasingly recognized as a source of recurrent symptoms in the young athletic hip. The hip capsule is of substantial importance in providing joint stability and normal biomechanics. Several recent studies have demonstrated that capsular closure at the time of primary hip arthroscopy improves both short‐ and long‐term patient‐reported outcomes, revision rates, and conversion to arthroplasty. Similarly, capsular insufficiency has been shown to be a source of recurrent pain and microinstability. Arthroscopic hip capsular management in the setting of chronic defects can be technically challenging, and far medial defects along the iliopsoas bursa are historically difficult to successfully repair because of challenging access and common lack of a proximal cuff of tissue for repair. We present an effective method for arthroscopic management of far medial hip capsular defects that consistently allows for reproducible capsular repair even in the absence of proximal capsular tissue. Technique Video video See video under supplementary data.

Purpose To determine the relationship between cam morphology of the hip and ipsilateral sacroiliac motion compared to the native hip in a cadaveric model. Methods A simulated cam state was created using a 3‐dimensional printed cam secured to the head‐neck junction of 5 cadaveric hips. Hips were studied using a computed tomography–based optic metrology system and a 6 degree‐of‐freedom robot to exert an internal rotation torque at 3 different torque levels (6 N‐m, 12 N‐m, 18 N‐m). Outcomes included translational and rotational movement about 3 axes and composite (total) translational motion at the ipsilateral sacroiliac (SI) joint. Statistical analysis included a linear mixed model regression with repeated measures. Results The presence of a simulated cam was associated with medial motion in the coronal plane ( P = .03) and posterior motion in the sagittal plane ( P < .01) but not composite motion ( P = .37). Motion in the axial plane was in an inferior direction ( P = .08). Cam morphology significantly changed rotation in the sagittal plane ( P < .01) but not in the coronal ( P = .63) or axial plane ( P = .18). Composite motion was related to the amount of torque applied to the hip ( P < .01). The amount of torque applied to the hip was related to rotation in the coronal plane ( P < .01), axial plane ( P < .01), and sagittal plane ( P < .01) with increased effects as torque increased. Torque was not associated with translation movement in any of the anatomic planes. Conclusions The presence of simulated cam morphology is associated with motion in a more medial, inferior, and posterior direction at the ipsilateral SI joint relative to a native state. Increasing torque affects the magnitude of translation, but not its direction, which in this study is primarily influenced by cam morphology. Clinical Relevance This biomechanical connection between cam‐type femoroacetabular impingement syndrome and the ipsilateral SI joint provides insight into SI joint dysfunction in patients with femoroacetabular impingement syndrome.

Background: Diagnosis of foveal triangular fibrocartilage complex (TFCC) tears remains difficult. The purpose of this study was to evaluate whether dynamic computed tomography (CT) of the distal radioulnar joint (DRUJ) has a higher sensitivity in detecting foveal tears of the TFCC when compared with magnetic resonance imaging (MRI). Methods: A database query identified all patients above the age of 18 years with suspected foveal TFCC injuries who underwent bilateral dynamic CT imaging of the DRUJ, static 3T MRI, and subsequent wrist arthroscopy. All patients had evidence of foveal tenderness on clinical examination. The imaging results were validated with wrist arthroscopy. Results: Twelve patients with a mean age of 31 years (range, 18-53 years) were identified. Eight patients were diagnosed with a complete foveal detachment of the TFCC on wrist arthroscopy. Of the 8 patients with a foveal tear on DRUJ arthroscopy, only 3 had a preoperative physical examination suggestive of DRUJ instability. Magnetic resonance imaging identified foveal injuries in 4 of these 8 patients (sensitivity, 50%), and 3 of these were identified as only partial tears. Dynamic CT identified instability of DRUJ in 6 of 8 patients (sensitivity, 75%). Seven of 8 patients had imaging findings suggestive of a foveal tear when including either MRI or CT imaging (sensitivity, 88%). Of the 4 patients with an intact foveal attachment on arthroscopy, 3 (specificity, 75%) had a stable DRUJ on CT and all 4 (specificity, 100%) had an intact foveal attachment on MRI. Conclusion: Sixty-two percent of patients with foveal tears on arthroscopy have a stable DRUJ on clinical examination. When combining MRI and dynamic CT imaging of the DRUJ, the sensitivity of detecting a foveal TFCC tear approaches 88% compared with a gold standard of wrist arthroscopy.

Purpose To (1) report the long‐term outcomes associated with both operative and nonoperative management of capitellar osteochondritis dissecans (OCD), (2) identify factors associated with failure of nonoperative management, and (3) determine whether delay in surgery affects final outcomes. Methods All patients who received a diagnosis of capitellar OCD from 1995‐2020 within a geographic cohort were included. Medical records, imaging studies, and operative reports were manually reviewed to record demographic data, treatment strategies, and outcomes. The cohort was divided into 3 groups: (1) nonoperative management, (2) early surgery, and (3) delayed surgery. Delayed surgery (surgery ≥6 months after symptom onset) was considered failure of nonoperative management. Results Fifty elbows with a mean follow‐up period of 10.5 years (median, 10.3 years; range, 1‐25 years) were studied. Of these, 7 (14%) were definitively treated nonoperatively, 16 (32%) underwent delayed surgery after at least 6 months of failed nonoperative treatment, and 27 (54%) underwent early surgical intervention. When compared with nonoperative management, surgical management resulted in superior Mayo Elbow Performance Index pain scores (40.1 vs 33, P = .04), fewer mechanical symptoms (9% vs 50%, P < .01), and better elbow flexion (141° vs 131°, P = .01) at long‐term follow‐up. Older patients trended toward increased failure of nonoperative management ( P = .06). The presence of an intra‐articular loose body predicted failure of nonoperative management ( P = .01; odds ratio, 13). Plain radiography and magnetic resonance imaging had poor sensitivities for identifying loose bodies (27% and 40%, respectively). Differences in outcomes after early versus delayed surgical management were not observed. Conclusions Nonoperative management of capitellar OCD failed 70% of the time. Elbows that did not undergo surgery had slightly more symptoms and decreased functional outcomes compared with those treated surgically. The greatest predictors of failure of nonoperative treatment were older age and presence of a loose body; however, an initial trial of nonoperative treatment did not adversely impact the success of future surgery. Level of Evidence Level III, retrospective cohort study.

Background: There are limited data on the incidence of capitellar osteochondritis dissecans (OCD) in the United States (US) population. Purpose: To determine the incidence of symptomatic capitellar OCD in a representative US subpopulation and identify changes in its incidence over time and to investigate the relationship between the incidence of capitellar OCD and patient sex and age. Study Design: Descriptive epidemiology study. Methods: A retrospective review was performed of patients aged ≤24 years from Olmsted County, Minnesota, with symptomatic capitellar OCD over a 25-year period (1995-2019). Patients with acute osteochondral injuries, Panner disease, and hereditary arthropathy were excluded. Poisson regression was utilized to identify the predictors of a capitellar OCD diagnosis. Incidence rates (per 100,000) were assessed for changes over time. Age groups of younger (10-15 years) versus older (16-24 years) patients were compared. Results: A total of 45 patients (78% male) were identified. The mean age was 14.5 years (range, 10-24 years); 31 patients were in the younger group, and 14 patients were in the older group. Sport participation was seen in 89%of patients; 90% were overhead athletes, and 58% were throwing athletes. The incidence of capitellar OCD was 6.0 per 100,000 overall, 9.5 per 100,000 for male patients, and 2.6 per 100,000 for female patients. The incidence was highest for male patients in the younger group (15.3/100,000) and lowest for female patients in the older group (0.8/100,000). The estimated incidence rate ratio for younger versus older patients was 3.3 ( P < .001), and the incidence rate ratio for male versus female patients was 3.5 ( P < .001). There were no changes in the incidence of capitellar OCD over time as a continuous or 5-year categorical variable ( P = .290 and P = .460, respectively). Overall, 82% of patients were treated surgically. There were no significant changes in surgical rates over time. Conclusion: In this US subpopulation, the overall incidence of symptomatic capitellar OCD between the ages of 10 and 24 years was 6.0 per 100,000 over the 25-year period studied, which is higher than previously reported US estimates. Incidence rates and treatment strategies did not change significantly over time.

Purpose: The purpose of this study is to compare pediatric hip aspiration in the operating room under general anesthesia or via bedside aspiration under moderate sedation and delineate the anesthetic time required. Methods: A database query conducted at two academic institutions identified all patients under the age of 17 who underwent hip aspiration between 2000 and 2017. At one institution, aspiration was performed in the operating room under general anesthesia. Patients were kept anesthetized until cell count was complete. At the second institution, aspiration was performed in the emergency room at bedside under sedation. The medical record was reviewed for demographic data, hip aspiration results, diagnoses, treatment, and anesthesia time. Results: A total of 233 patients (233 hips) with a mean age of 7.2 years were identified. Seventy-five patients underwent aspiration in the operating room, and 158 patients underwent bedside aspiration. Patients with a negative aspiration averaged 87 min under anesthesia when performed in the operating room and 29 min under sedation when performed at bedside. Patients with a negative aspiration performed in the operating room after 5 pm averaged 99 min under anesthesia, and 73 min under anesthesia when performed between 7 am and 5 pm (p < 0.01). Seventy-eight (49%) patients who underwent bedside aspiration did not require operative intervention and therefore avoided general anesthesia. Conclusion: Pediatric hip aspiration performed in the operating room results in prolonged anesthesia times while synovial fluid is transported and processed. Anesthesia times are significantly longer after 5 pm. Bedside aspiration resulted in significantly less anesthesia exposure, with half of patients undergoing bedside aspiration avoiding general anesthesia altogether. Level of evidence: Level III.

AbstractIntroductionThe proximal humerus is a common location for primary and non‐primary tumors. Reconstruction of the proximal humerus is commonly performed with an endoprosthesis with low rates of structural failure. The incidence and risk factors for stress shielding are under reported.MethodsThirty‐nine (19 male, 20 female) patients underwent resection of the proximal humerus and reconstruction with a cemented modular endoprosthesis between 2000 and 2018. The mean resection length was 12 ± 4 cm and was most commonly performed for metastatic disease (n = 26, 67%).ResultsStress shielding was observed in 9 (23%) patients at a mean of 29 (6–132) months postoperatively. Patients with stress shielding were noted to have shorter intramedullary stem length (87 vs. 107 mm, p < .001), longer extramedullary implant length (16 vs. 14 cm, p = .01) and a higher extramedullary implant to stem length ratio (2.1 vs. 1.1, p < .001). The incidence of stress shielding was higher (p = .003) in patients reconstructed with 75 mm stem (n = 6, 67%) lengths.ConclusionStress shielding of the humerus was associated with the use of shorter stems and long extramedullary implants. The long‐term ramifications of stress shielding on implant stability, complications at the time of revision surgery, and overall patient outcomes remain unknown.