O’Driscoll, Shawn W.

Background Persistent infection rate after 2-stage reimplantation complicating elbow arthroplasty has been reported to be as high as 25%. The purposes of this retrospective study were to determine the infection eradication rates, complications and outcomes in a cohort of patients treated with two-stage reimplantation for deep periprosthetic joint infection (PJI) following total elbow arthroplasty (TEA) and to determine possible associated risk factors for treatment failure. Methods Between 2000 and 2017, 52 elbows underwent a two-stage reimplantation for PJI after TEA. There were 22 males and 30 females with a mean age of 61 (range, 25–82) years. The most common bacterium was Staphylococcus epidermidis (28 elbows). Mayo Elbow Performance Scores were calculated at the latest follow-up. Mean follow-up time was 6 years (range, 2–14 years). Results PJI was eradicated in 36 elbows (69%). The remaining 16 elbows were considered treatment failures secondary to recurrent infection. The risk of persistent infection was 3.3 times higher in elbows with retained cement (p 0.04), and 3.5 times higher when the infecting organism was Staphylococcus epidermidis (p 0.06). Conclusion Two-stage reimplantation for PJI after TEA was successful in eradicating deep infection in 69% of cases. The eradication of PJI after TEA still needs to be improved substantially.

Background: Osteochondritis dissecans (OCD) of the capitellum is common in throwing athletes and is believed to result from repetitive overloading on the radiocapitellar (RC) joint, although the cause and mechanism remain unclear. The torsional forces (moments) generated by the triceps during elbow extension pull only on the ulna; therefore, the radial head moves passively across the capitellum and is effectively “dragged along” by the ulna. Any laxity in the proximal radioulnar joint could lead to asynchronous motion between the radius and ulna, resulting in the radial head lagging behind the coronoid and possibly malarticulating with the capitellum during such motion. Hypothesis: Radial head motion on the capitellum lags behind ulnohumeral joint motion during simulated throwing. Study Design: Controlled laboratory study. Methods: A total of 8 cadaveric elbows were tested under simulated throwing, including active extension of the elbow generated by pulling of the triceps under valgus stress, as well as during passive extension under valgus stress to serve as a reference. Ulnohumeral motion was tracked using a video camera. Radial head motion was tracked using an intra-articular, thin-film pressure sensor mounted on the capitellum, and the longitudinal movement of the center of force (COF) of the radial head was measured. Radial head motion was compared between passive and active motion for each 10° of elbow extension from 90° to 20°. Results: Elbow motion during simulated active extension reached an angular velocity of 366 deg/s. Radial head motion during simulated active extension significantly lagged compared with its motion during passive extension at every elbow extension angle examined between 70° and 20° ( P < .001). The maximal lag reached a mean of 4 mm (range, 2-7 mm). In other words, RC and ulnohumeral motion were asynchronous during simulated throwing. Conclusion: This study describes a novel phenomenon: motion of the radial head across the capitellum during rapid extension, such as in baseball pitching, lags behind that seen during passive elbow motion. According to a new proposed theory of OCD lesion development, this lag should result in RC incongruency and elevated shear forces on the capitellum due to edge loading. Clinical Relevance: We propose a new biomechanical explanation for OCD of the capitellum in baseball pitchers: radial head lag. Understanding this process is the first step in efforts to prevent this common injury.

Purpose To analyze the available literature pertaining to the indications, outcomes, and complications of both microfracture (MFX) and simple debridement for capitellar osteochondritis dissecans (OCD). Methods A comprehensive literature review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) criteria. Studies were included if they evaluated OCD of the capitellum that underwent either arthroscopic debridement (AD) or MFX. The risk of bias was assessed using the Methodological Index for Non‐randomized Studies (MINORS) scale. Patient demographic characteristics, imaging findings, return‐to‐sport rates, patient‐reported outcomes, range of motion (ROM), complications, failures, and reoperations were recorded. Results Eleven studies with 327 patients (332 elbows) met the inclusion criteria. Methodological Index for Non‐randomized Studies (MINORS) scores ranged from 63% to 75% and showed considerable heterogeneity. Both AD and MFX showed improvement in patient outcome scores, ROM, and return to play, although the data precluded relative conclusions. Improvement in motion after MFX ranged from 4.9° to 5° of flexion, 5° to 22.6° of extension, 1° to 2° of pronation, and 0.5° to 2° of supination, whereas after AD, it ranged from –4° to 6° of flexion and –0.4° to 14° of extension, with prono‐supination noted in only 1 study. The rate of return to play at a similar level of preinjury athletic competition ranged from 55% to 75% after MFX and from 40% to 100% after AD. Lesion location was discussed in only 1 study. Postoperative imaging trended toward early degenerative changes, most commonly of the radial head. Complications were only reported in 1 MFX study; in all cases, the complication was transient ulnar nerve neurapraxia. Reoperation rates ranged from 0% to 10%, and reoperation was most commonly performed to address radial head enlargement. Five studies reported no reoperations. Conclusions Both AD and MFX for capitellar OCD appear to yield excellent improvements in pain, ROM, patient outcome scores, and return to sport. Given that comparable mid‐term outcomes can be achieved with debridement alone, without the use of MFX, similarly to recent prospective studies in the knee, AD alone may be a reasonable approach to relatively small OCD defects. Level of Evidence Level IV, systematic review of studies, all Level IV evidence.

Osteochondritis Dissecans (OCD) is a joint defect in which a crack in thesubchondral bone causes a separation of both subchondral bone and overlying cartilage from the bulk of the bone. Because there is an increased prevalence of OCD among youth athletes, an efficient, accurate, and non-ionizing screening method for this condition is being pursued. The aim of this project is to develop a clinical ultrasound image reconstruction algorithm that increases the detectability of bone surface defects, such as OCD. The proposed algorithm is a modified delay-multiply-and-sum (DMAS) algorithm that uses data acquired through synthetic aperture methods. The modifications made to the DMAS algorithm relevant to this work include transmit apodization and incoherent data summation. The modified DMAS algorithm was tested on data generated from k-Wave simulations and validated with experiments using bone mimicking material. Using both k-Wave and the bone mimicking material, we modeled fractures in the capitellum of the humerus with separations of 1, 2, and 3 mm. For experiments, we used synthetic aperture acquisitions using a Verasonics V1 system with a linear array (L7-4). The modified DMAS algorithm was found to enhance the clarity of bone surface defects when compared against DAS and DMAS algorithms.

Background: The rate of elbow medial ulnar collateral ligament (MUCL) injury and surgery continues to rise steadily. While authors have failed to reach a consensus on the optimal graft or anchor configuration for MUCL reconstruction, the vast majority of the literature is focused on the young, elite athlete population utilizing autograft. These studies may not be as applicable for the “weekend warrior” type of patient or for young kids playing on high school leagues or recreationally without the intent or aspiration to participate at an elite level. Purpose: To investigate the clinical outcomes and complication rates of MUCL reconstruction utilizing only allograft sources in nonelite athletes. Study Design: Case series; Level of evidence, 4. Methods: Patient records were retrospectively analyzed for individuals who underwent allograft MUCL reconstruction at a single institution between 2000 and 2016. A total of 25 patients met inclusion criteria as laborers or nonelite (not collegiate or professional) athletes with a minimum of 2 years of postoperative follow-up. A review of the medical records for the included patients was performed to determine survivorship free of reoperation, complications, and clinical outcomes with use of the Summary Outcome Determination (SOD) and Timmerman-Andrews scores. Statistical analysis included a Wilcoxon rank-sum test to compare continuous variables between groups with an alpha level set at .05 for significance. Subgroup analysis included comparing outcome scores based on the allograft type used. Results: Twenty-five patients met all inclusion and exclusion criteria. The mean time to follow-up was 91 months (range, 25-195 months), and the mean age at the time of surgery was 25 years (range, 12-65 years). There were no revision operations for recurrent instability. The mean SOD score was 9 (range, 5-10) at the most recent follow-up, and the Timmerman-Andrews scores averaged 97 (range, 80-100). Three patients underwent subsequent surgical procedures for ulnar neuropathy (n = 2) and contracture (n = 1), and 1 patient underwent surgical intervention for combined ulnar neuropathy and contracture. Conclusion: Allograft MUCL reconstruction in nonelite athletes demonstrates comparable functional scores with many previously reported autograft outcomes in elite athletes. These results may be informative for elbow surgeons who wish to avoid autograft morbidity in common laborers and nonelite athletes with MUCL incompetency.

Background: When revision elbow arthroplasty is required in the presence of structural proximal ulnar bone loss and triceps insufficiency, structural ulnar bone-grafting and triceps reconstruction are both required to reconstruct the skeleton and to restore active extension. We have developed a technique utilizing a structural proximal ulnar allograft with its attached triceps as an allograft-prosthetic composite (APC) to provide reconstruction of the proximal ulnar bone and deficient extensor mechanism with the same allograft. Methods: Between 2010 and 2017, the senior author performed 10 revision elbow arthroplasties using a proximal ulnar allograft with its intact triceps tendon allograft. The allograft ulna was combined with an ulnar component in an APC fashion, whereas the remaining triceps was repaired to the triceps allograft. Indications for a revision surgical procedure included aseptic loosening in 4 elbows, periprosthetic ulnar fracture with component loosening in 2 elbows, and the second stage of a 2-stage reimplantation in 4 elbows. Two elbows also required humeral APCs due to associated structural humeral bone loss. Postoperatively, all elbows were immobilized in extension for 6 weeks. The mean follow-up time was 45 months (range, 24 to 76 months). Results: Revision elbow arthroplasty resulted in pain improvement in all elbows in a 10-point visual analog scale. The mean flexion-extension arc was 95°, the mean Mayo Elbow Performance Score was 76 points (range, 45 to 95 points), and the mean triceps strength score was 4. There were 6 reoperations: 3 for humeral loosening, 1 for deep infection, 1 for fracture of the ulnar allograft, and 1 for wound debridement and closure. For the 8 elbows with an intact ulnar reconstruction, no ulnar components were radiographically loose, and the ulnar graft was considered radiographically intact and healed in 8 elbows. Conclusions: Reconstruction of the proximal part of the ulna and triceps in failed elbow arthroplasties with structural ulnar bone loss can be effectively accomplished using a structural proximal ulnar allograft as an APC with the preserved triceps tendon for the extensor mechanism reconstruction, but the procedure is associated with an expected high reoperation rate, as is the case in complex revision elbow arthroplasty. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Purpose To systematically evaluate the outcomes and complications of osteochondral autograft transfer (OAT) and osteochondral allograft transplantation (OCA) for the surgical treatment of capitellar osteochondritis dissecans (OCD). Methods A literature search was conducted across 3 databases (PubMed, Cochrane, and CINAHL [Cumulative Index to Nursing and Allied Health Literature]) from database inception through December 2019 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) guidelines. Individual study quality was assessed using the Methodological Index for Non‐randomized Studies scale. Studies were published between 2005 and 2019. Results Eighteen studies consisting of 446 elbow OCD lesions treated with OAT surgery were included. There was a single OCA study eligible for inclusion. Patient ages ranged from 10 to 45 years. Of the OAT studies, 4 used autologous costal grafts whereas the remainder used autografts from the knee. Outcome measures were heterogeneously reported. A significant improvement in Timmerman‐Andrews scores from preoperatively to postoperatively was reported in 9 of 10 studies. Return‐to‐play rates to the preinjury level of competitive play ranged from 62% to 100% across 16 studies. Significant improvement in motion, most often extension, was noted in most studies. Reported complication, reoperation, and failure rates ranged from 0% to 11%, 0% to 26%, and 0% to 20%, respectively. When used, knee autografts resulted in low donor‐site morbidity (Lysholm scores, 70‐100). Conclusions OAT surgery for large, unstable OCD lesions of the capitellum reliably produced good outcomes, few complications, and a high rate of return to competitive play. Complications are relatively uncommon, and donor‐site morbidity is low. Less is known about the performance of OCA given the paucity of available literature. Level of Evidence Level IV, systematic review of Level II to IV studies.

Purpose To analyze the complications of arthroscopic heterotopic ossification (HO) excision and compare them with those of open removal of HO or a combined open‐arthroscopic approach. Methods We performed a retrospective review of elbow HO removal cases performed by a single surgeon from 1997 to 2014. In all cases studied, the intention was to restore range of motion owing to the presence of HO causing functional impairment. The arthroscopic, open, and combined treatment groups were compared. Results The study cohort consisted of 223 surgical procedures performed on 213 elbows in 211 patients. Fifty major complications occurred in 46 cases (21%): 17 hematomas (8%) treated by irrigation and debridement, 8 cases of HO requiring reoperation (4%), 7 deep infections (3%), 4 contractures (2%), 3 cases of delayed‐onset ulnar neuritis (1%), 2 cases of distal humeral avascular necrosis (1%), 2 tendon ruptures (1%), 2 cases of instability requiring reconstruction (1%), 2 postoperative fractures (1%), 1 intraoperative fracture (<0.5%), 1 case of worsening of pre‐existing neuropathic pain (<0.5%), and 1 permanent partial posterior interosseous nerve injury (<0.5%). Of these 46 cases, the major complications occurred in 6 of the 41 (15%) performed arthroscopically, in 36 of the 158 (23%) performed open and in 4 of the 21 (17%) with combined (i.e. open + arthroscopic) HO removal. Preventive strategies, introduced to prevent hematomas and delayed‐onset ulnar neuritis, reduced the rate of major complications from 35% during the period from 1997 to 2005 to 10% during the period from 2006 to 2014 ( P < .0001). Moreover, the rate of reoperations was reduced from 34% to 10% in the same periods ( P < .0001). Minor complications occurred in 36 cases (16%), including 17 cases of transient nerve palsy, 9 cases of superficial infection or delayed wound healing, 6 cases of mild instability, and 4 cases of hematoma resolved by aspiration. Conclusions The use of arthroscopy—or a combination of arthroscopic and open techniques—to remove HO around the elbow by a surgeon skilled in both arthroscopic and open elbow surgery does not increase the risk of major complications or need for reoperation compared with traditional open surgery. Preventive strategies, such as avoiding raising skin flaps by using multiple separate incisions for open and prophylactic ulnar nerve decompression in arthroscopic cases, were developed during the study period. These strategies were monitored prospectively and found to be effective in preventing two‐thirds of the major complications needing reoperation with both open and arthroscopic HO removal. Level of Evidence Level III, retrospective comparative study of prospectively collected data.

Background Over-lengthening of the radial neck has been shown to affect ulnohumeral kinematics and has been proposed to affect radiocapitellar pressures. We hypothesized that an incremental increase in radial neck height increases the capitellar contact pressure and reduces the coronoid contact pressure. Knowledge of the effects of over-lengthening is clinically important in preventing pain and degenerative changes due to overstuffing. Methods Six human cadaveric elbows were prepared on a custom-designed apparatus simulating muscle loads and passive flexion from 0° to 90° under gravity valgus torque while measuring joint contact pressures in this biomechanical study. Each elbow was tested sequentially starting with the intact specimen followed by insertion of a radial head prosthesis with 0, +2, and +4 mm of radial neck height, respectively. Results Capitellar mean contact pressures significantly increased after insertion of +2 and +4 mm radial head prostheses (p < 0.03). The capitellar mean contact pressure with a 0 mm radial head prosthesis was 97 KPa. Insertion of +2 mm and +4 mm radial heads increased mean contact pressures to 391 KPa (p = 0.001) and 619 KPa (p = 0.001), respectively, with 90° of elbow flexion. Discussion Increasing radial prosthesis height by 2 mm significantly increases capitellar contact pressures and reduces coronoid contact pressures.

Background To determine if self-taken photographs (“selfies”), performed independently after instruction by video or illustrated handout, would be an accurate and reliable tool for capturing elbow range of motion in patients with elbow contractures. Methods Fifty patients presenting with elbow contractures participated in the study. After completion of the selfie, the senior author clinically measured flexion and extension with a goniometer. The angles from the photographs were measured and analyzed. Results The agreement between goniometer and “selfie” measurements correlated closely (R 2 = 0.98) and agreement was excellent in both extension and in flexion with intra-class correlation coefficients of 0.95 (95% CI 0.92 to 0.97) in extension with a mean difference of 2° (95% CI −3° to 7°), and 0.93 (95% CI 0.89 to 0.96) in flexion with a mean difference of 4° (95% CI 0° to 8°). Systematic errors were low in extension, 0° (95% CI, ±11°) and in flexion −3° (95% CI, ±10°). Six patients demonstrated ≥10° difference between clinical and selfie measurements. Ability to take a usable selfie was inversely correlated with age (R 2 = 0.97). Discussion Self-taken flexion–extension photographs are a reliable and accurate tool for measuring elbow range of motion. Errors in the selfie technique are well tolerated and appear to have a negligible effect upon measurements of motion. This important parameter of elbow function can therefore be obtained outside a normal clinic visit, thereby improving frequency of follow-up assessments (and minimizing loss to follow-up) necessary for quality control and research.