Citations

Background: With the expanding use of reverse shoulder arthroplasty (RSA) to treat various shoulder conditions, there has been a rise in the number of RSAs performed, especially in physically active patients. Limited information regarding sports after RSA is available to properly counsel patients on postoperative expectations. Purpose: To assess the rate of return to sports as well as the ability to return to the same level of preoperative intensity, frequency, and duration of sport after primary RSA. Study Design: Case series; Level of evidence, 4. Methods: This was a retrospective review of patients who underwent primary RSA at our institution between 2014 and 2016. Shoulder motion, Subjective Shoulder Value score, American Shoulder and Elbow Surgeons score, pre- and postoperative sports activities, and barriers to return to sport were assessed in 109 patients after RSA (93 patients with unilateral RSA and 16 patients with bilateral RSA). The mean age at the time of surgery was 70 years (range, 34-86 years), with a mean follow-up of 3.9 years (range, 2-12 years). Results: The mean rate of return to sports was 70.1% (range, 0%-100%). There was no difference in return to sports between those with uni- and bilateral RSA ( P = .64). Fishing, swimming, elliptical/treadmill, and hunting were the most common sports after RSA with return rates of 91%, 73%, 86%, and 82% respectively. A majority of patients returned to the same level of preoperative intensity, frequency, and duration for all sports except for climbing and swimming. There was a lower mean rate of return for high-demand sports (62.9%) compared with low- and medium-demand sports (76.7%) ( P = .005). The most common reasons for inability to return to sports included limited motion, fear of injury, and weakness. Conclusion: Patients who had undergone primary uni- or bilateral RSA reported a 70.1% rate of return to sports with maintenance of the same level of intensity, duration, and frequency of preoperative sport participation. Rates of return to high-demand sports were lower than low- and medium-demand sports. Patients also had difficulty returning to overhead sports.

Background: In a study from our institution, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon for recalcitrant lateral elbow tendinopathy showed excellent safety profiles, high tolerability, efficiency, sustained pain relief, functional improvement, and sonographic evidence of tissue healing in 20 patients at 3 years’ follow-up. Purpose: To explore the long-term clinical and sonographic results of ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon. Study Design: Case series; Level of evidence, 4. Methods: The same cohort of 20 patients was recalled after 7 years, and visual analog scale (VAS) for pain and Disabilities of the Arm, Shoulder and Hand (DASH) scores, need for secondary intervention, and overall satisfaction were assessed. They were also reassessed using ultrasound imaging of the brevis and the common extensor tendon to evaluate tendon hypervascularity, tendon thickness, and the progress or the recurrence of the hypoechoic scar tissue. Results: We successfully scored 19 patients and performed ultrasound on 16 patients with a median follow-up of 90 months (range, 86-102 months). There were no adverse outcomes and satisfaction remained at 100% (6 patients, satisfied; 13 patients, very satisfied). No patient developed a recurrence of symptoms and signs of lateral elbow tendinopathy, and therefore no secondary intervention was required. The improvement from baseline and early term scores was sustained ( P < .001 for all). At 90 months, there was a significant improvement in VAS scores and DASH–Compulsory scores compared with preprocedure scores and all follow-up times until 3 months. There was no difference in VAS scores and DASH–Compulsory scores at 90 months compared with 6 and 36 months. For DASH–Work scores, there was a significant improvement at 90 months compared with preprocedure scores, but there was no difference between DASH–Work scores at 90 months and scores at all other points of follow-up. At 90 months, hypervascularity remained resolved in 79% of patients, while all patients had reduced tendon swelling and sustained resolution or reduction of the hypoechoic lesion. Conclusion: At the long-term follow-up of 90 months, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon, previously shown to enhance recovery of lateral elbow tendinopathy, demonstrated good durability of pain relief and functional recovery that was previously achieved. This was accompanied by sustained sonographic tissue healing with no significant deterioration.

AbstractExperimental analyses of posttraumatic knee arthrofibrosis utilize a rabbit model as a gold standard. However, a rodent model of arthrofibrosis offers many advantages including reduced cost and comparison with other models of organ fibrosis. This study aimed to characterize the biomechanical, histological, and molecular features of a novel posttraumatic model of arthrofibrosis in rats. Forty eight rats were divided into two equal groups. An immobilization procedure was performed on the right hind limbs of experimental rats. One group was immobilized for 4 weeks and the other for 8 weeks. Both groups were remobilized for 4 weeks. Limbs were studied biomechanically via assessment of torque versus degree of extension, histologically via whole knee specimen, and molecularly via gene expression of posterior capsular tissues. Significant differences were observed between experimental and control limbs at 4 N‐cm of torque in the 4‐week (knee extension: 115° ± 8° vs. 169° ± 17°, respectively; p = 0.007) and 8‐week immobilization groups (knee extension: 99° ± 12° vs. 174° ± 9°, respectively; p = 0.008). Histologically, in each group experimental limbs demonstrated increased posterior capsular thickness and total area of tissue when compared to control limbs (p < 0.05). Gene expression values evaluated in each group were comparable. This study presents a novel rat model of arthrofibrosis with severe and persistent knee contractures demonstrated biomechanically and histologically. Statement of clinical significance: Arthrofibrosis is a common complication following contemporary total knee arthroplasties. The proposed model is reproducible, cost‐effective, and can be employed for translational investigations studying the pathogenesis of arthrofibrosis and efficacy of neoadjuvant pharmacologic agents.

Abstract Guidelines for using finite element to model cortical defects were established by determining the consequences for solution accuracy of various modeling strategies. Solution accuracy was established by comparing finite element results to an existing experimental benchmark for the torsion of circular tubes that contained transverse through circular holes. A new automated modeling approach was developed that could be used to support clinical modeling of cortical defects.

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.

(1) Background: Arthrofibrosis is a common cause of patient debility and dissatisfaction after total knee arthroplasty (TKA). The diversity of molecular pathways involved in arthrofibrosis disease progression suggest that effective treatments for arthrofibrosis may require a multimodal approach to counter the complex cellular mechanisms that direct disease pathogenesis. In this study, we leveraged RNA-seq data to define genes that are suppressed in arthrofibrosis patients and identified adiponectin (ADIPOQ) as a potential candidate. We hypothesized that signaling pathways activated by ADIPOQ and the cognate receptors ADIPOR1 and ADIPOR2 may prevent fibrosis-related events that contribute to arthrofibrosis. (2) Methods: Therefore, ADIPOR1 and ADIPOR2 were analyzed in a TGFβ1 inducible cell model for human myofibroblastogenesis by both loss- and gain-of-function experiments. (3) Results: Treatment with AdipoRon, which is a small molecule agonist of ADIPOR1 and ADIPOR2, decreased expression of collagens (COL1A1, COL3A1, and COL6A1) and the myofibroblast marker smooth muscle α-actin (ACTA2) at both mRNA and protein levels in basal and TGFβ1-induced cells. (4) Conclusions: Thus, ADIPOR1 and ADIPOR2 represent potential drug targets that may attenuate the pathogenesis of arthrofibrosis by suppressing TGFβ-dependent induction of myofibroblasts. These findings also suggest that AdipoRon therapy may reduce the development of arthrofibrosis by mediating anti-fibrotic effects in joint capsular tissues.

AbstractIntroductionThe proximal humerus is a common site of primary and metastatic disease in the upper extremity. Historically, the goal of a hemiarthroplasty reconstruction was to provide a stable platform for hand and elbow function, with limited shoulder function. Techniques utilizing a reverse endoprosthesis (endoprosthetic replacement [EPR]) and allograft‐prosthetic composite (APC) have been developed; however, there is a paucity of comparative studies.MethodsA total of 83 (42 females, 41 males) patients undergoing an intraarticular resection of the humerus were reviewed. Reconstructions included 30 reverse and 53 hemiarthroplasty; including hemiarthroplasty EPR (n = 36) and APC (n = 17), and reverse EPR (n = 20) and APC (n = 10).ResultsReverse reconstructions had improved forward elevation (85° vs. 44°, p < .001) and external rotation (30° vs. 21°; p < .001) versus a hemiarthroplasty. Reverse reconstructions had improved American Shoulder and Elbow Surgeons scores (65 vs. 57; p = .01) and Musculoskeletal Tumor Society 93 scores (72 vs. 63; p < .001) versus hemiarthroplasty. Subluxation of the reconstruction was a common (n = 23, 27%), only occurring in hemiarthroplasty patients (EPR [n = 13, 36%] and APC [n = 10, 59%]).ConclusionThe current series highlights the improved functional outcome in patients undergoing reconstruction with a reverse arthroplasty compared to the traditional hemiarthroplasty. Currently reverse shoulder arthroplasty (APC or EPR) is our preferred methods of reconstruction in this patient population.

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.

Aims Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits. Methods A group of 12 skeletally mature rabbits were randomly divided into two groups. One group received subcutaneous (SQ) saline, and a second group received SQ ketotifen injections. Biomechanical data were collected at eight, ten, 16, and 24 weeks. At the time of necropsy, posterior capsule tissue was collected for histopathological and gene expression analyses (messenger RNA (mRNA) and protein). Results At the 24-week timepoint, there was a statistically significant increase in passive extension among rabbits treated with ketotifen compared to those treated with saline (p = 0.03). However, no difference in capsular stiffness was detected. Histopathological data failed to demonstrate a decrease in the density of fibrous tissue or a decrease in α-smooth muscle actin (α-SMA) staining with ketotifen treatment. In contrast, tryptase and α-SMA protein expression in the ketotifen group were decreased when compared to saline controls (p = 0.007 and p = 0.01, respectively). Furthermore, there was a significant decrease in α-SMA (ACTA2) gene expression in the ketotifen group compared to the control group (p < 0.001). Conclusion Collectively, these data suggest that ketotifen mitigates the severity of contracture formation in a rabbit model of arthrofibrosis. Cite this article: Bone Joint Res 2020;9(6):302–310.

Abstract Cite this article: EFORT Open Rev 2020;5:354-360. DOI: 10.1302/2058-5241.5.200299