Asty. Methods: Between 2005 and 2010, 143 consecutive reverse shoulder arthroplasties performed as revision procedures were performed at our institution. Glenoid bone-grafting was performed in forty-one shoulders (29%), with 98% (forty) that had follow-up of more than two years (mean, 3.1 years). The 102 patients who did not undergo grafting served as a control group. Results: Seven patients (18%) required another revision surgery because of glenoid loosening (four patients), instability (two patients), or infection (one patient). The two and five-year implant survival rate free of revision for shoulders that had glenoid bone-grafting was 88% and 76%, respectively, which was lower than that for patients who had not required glenoid bone-grafting. The survival rate free of radiographic glenoid loosening at two and five years for the shoulders that had bone-grafting was 92% and 89%, respectively, which was worse than that for those that had not had glenoid bone-grafting. Patients had significant pain relief and improvement in their shoulder range of motion, and they had an increased level of satisfaction compared with the preoperative status. Increased rates of glenoid loosening were seen in patients who had an increased body mass index, an implant with a lateral center of rotation, a previous total shoulder replacement (versus hemiarthroplasty), and in those who were smokers. Conclusions: Although there were relatively high rates of glenoid loosening and reoperation at mid-term follow-up, glenoid reconstruction with bone graft in the revision setting was able to relieve pain and restore shoulder function and stability. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence....

Background: Although obesity is associated with increased complication rates after lower-extremity arthroplasty, there is a relative paucity of studies examining the effect of body mass index (BMI) on shoulder arthroplasty. The purpose of this investigation was to evaluate the effect of BMI on implant survival and the rate of complications after shoulder arthroplasty. Methods: Using an institutional total joint registry, 4,567 consecutive shoulder arthroplasty cases from 1970 to 2013 were studied. The mean BMI was 29.7 kg/m² (range, 14 to 66 kg/m²), with 1,622 patients (36%) with a BMI of 30 to 40 kg/m² and 297 patients (7%) with a BMI of >40 kg/m². There were 2,493 female patients (55%). BMI was dichotomized after examination of the smoothing spline curve. The associations of factors and complications were assessed using Cox proportional hazard regression analysis. Results: Increasing BMI was associated with an increased risk of a revision surgical procedure, reoperation, revision for mechanical failure, and superficial infection, and it was negatively associated with risk of a periprosthetic fracture. The risk of a revision surgical procedure increased in a linear fashion with increasing BMI (hazard ratio [HR], 1.05, or a 5% increased risk per 1 unit of BMI; p = 0.03). Increased BMI was also associated with an increased risk of revision for mechanical failure (HR, 1.05; p = 0.004). In a multivariate model, the association of BMI and risk of a revision for any reason, revision for mechanical failure, and reoperation maintained significance (p ≤ 0.02). The most marked association between increasing BMI and any complication in shoulder arthroplasty was its association with superficial wound infection (HR, 1.09; p = 0.03). Conclusions: Increasing BMI is strongly associated with increased rates of revision surgical procedures and postoperative complications after shoulder arthroplasty. It is important to consider these findings when counseling patients, estimating risks, and estimating complication risks in policy decisions. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Reverse total shoulder arthroplasty (RTSA) performed in the setting of massive proximal humeral bone loss often requires special reconstructive techniques. Restoration of the proximal part of the humerus with an allograft provides a number of theoretical benefits, including implant support, restoration of humeral length, deltoid tensioning, and an opportunity to repair the posterior aspect of the cuff to improve strength in external rotation and repair of the subscapularis to improve stability. However, reverse allograft-prosthesis composites (APCs) are costly, are technically demanding to use, and can be compromised by progressive allograft resorption. Methods: Between 2005 and 2012, the lead author used an APC reconstruction in 8 primary and 18 revision RTSAs (26 patients; mean age, 62 years; mean body mass index, 27.9 kg/m²). The indications for the primary RTSAs included severe proximal humeral bone loss after trauma (n = 5) and tumor resection (n = 3). The indications in the revision setting were failed hemiarthroplasty (n = 11), anatomic total shoulder arthroplasty (n = 4), and reverse arthroplasty (n = 3). The most common reason for revision was instability (n = 10). A compression plate was used for graft-to-host fixation in all shoulders. Shoulders were assessed for pain, motion, American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST) score, Neer score, revision or reoperation, radiographic evidence of graft union or resorption, and implant fixation. The mean duration of follow-up was 4 years (range, 2 to 10 years). Results: RTSA using an APC construct resulted in substantial improvements in pain scores (p < 0.0001), elevation (p < 0.0001), and external rotation (p = 0.004). With the numbers available, there were no significant differences in clinical outcomes between primary and revision cases. No patients required revision surgery for nonunion at the host-allograft junction. The mean time to union was 7 months, with 1 patient requiring bone-grafting for delayed union. Other complications included dislocation, deep infection, graft fracture, and periprosthetic fracture distal to the previous APC construct in 1 patient each. The 2 and 5-year revision-free survival rate was 96%. Conclusions: Reconstruction of proximal humeral bone loss with an APC at the time of primary or revision RTSA is safe and effective, with acceptable functional outcomes and complication rates. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Morbid obesity (BMI [body mass index], ≥40 kg/m2) is associated with a higher risk of complications, including infection and implant failure, following primary total hip arthroplasty. The purpose of this study was to compare the results of two-stage revision total hip arthroplasty for infection in a morbidly obese patient cohort (BMI, ≥40 kg/m2) and nonobese patients (BMI, <30 kg/m2). Using an institutional total joint registry, we reviewed the medical records of 653 patients treated with two-stage revision total hip arthroplasty for periprosthetic joint infection over a twenty-year period (1987 to 2007). Patients were stratified according to preoperative BMI. Thirty-three patients (fourteen male and nineteen female) with a BMI of ≥40 kg/m2 were identified. These patients were matched 1:2 with a cohort of sixty-six patients (twenty-eight male and thirty-eight female) of the same sex and similar age (91% within two years) who were not obese (BMI, <30 kg/m2). All patients had a minimum of five years of clinical follow-up (mean, 8.1 years in the morbidly obese group and 10.3 years in the nonobese group). Compared with nonobese patients, morbidly obese patients had significantly greater rates of reinfection (18% compared with 2%, p < 0.005), revision (42% compared with 11%, p < 0.001) and reoperation for any reason (61% compared with 12%, p < 0.001). Prior to surgery, the mean Harris Hip Score had been 50.6 in the morbidly obese group and 48.8 in the nonobese group, and these scores improved significantly in both groups postoperatively (p < 0.01). Morbidly obese patients have markedly elevated risks of reinfection, reoperation, and component resection as well as poorer intermediate-term clinical outcome scores compared with nonobese patients following revision total hip arthroplasty for periprosthetic joint infection. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Osteoarthritis (OA) is a painful chronic condition with a significant impact on quality of life. The societal burden imposed by OA is increasing in parallel with the aging population; however, no therapies have demonstrated efficacy in preventing the progression of this degenerative joint disease. Current mainstays of therapy include activity modification, conservative pain management strategies, weight loss, and if necessary, replacement of the affected joint. Mesenchymal stem cells (MSCs) are a multipotent endogenous population of progenitors capable of differentiation to musculoskeletal tissues. MSCs have a well-documented immunomodulatory role, managing the inflammatory response primarily through paracrine signaling. Given these properties, MSCs have been proposed as a potential regenerative cell therapy source for patients with OA. Research efforts are focused on determining the ideal source for derivation, as MSCs are native to several tissues. Furthermore, optimizing the mode of delivery remains a challenge both for appropriate localization of MSCs and for directed guidance toward stemming the local inflammatory process and initiating a regenerative response. Scaffolds and matrices with growth factor adjuvants may prove critical in this effort. The purpose of this review is to summarize the current state of MSC-based therapeutics for OA and discuss potential barriers that must be overcome for successful implementation of cell-based therapy as a routine treatment strategy in orthopedics.