Faculty Bibliography

OBJECTIVES/OBJECTIVE:To determine the effect of osteonecrosis (ON) on the clinical and functional outcome after open reduction and internal fixation of proximal humerus fractures. DESIGN/METHODS:Prospective cohort study. SETTING/METHODS:Academic medical center. PATIENTS/METHODS:Over a 12-year period, patients were screened and identified on presentation to the emergency department or in the clinical office for inclusion in an institutional review board-approved registry. One hundred sixty-five patients with 166 proximal humerus fractures met inclusion criteria. Eight patients developed radiographic evidence of ON (4.8%). INTERVENTION/METHODS:Surgical repair of proximal humerus fractures. MAIN OUTCOME MEASURE/METHODS:Patients were divided into 2 cohorts; 1 cohort being those diagnosed with ON and the other cohort being those who were not. All patients were prospectively followed and assessed for clinical and functional outcomes at the latest follow-up visit (mean = 22.9 months) using the Disabilities of Arm, Shoulder and Hand survey along with ranges of motion of the injured extremity. RESULTS:Average postoperative forward elevation for patients with ON was worse than those without ON (P = 0.002). Additionally, there was a significant difference in Disabilities of Arm, Shoulder and Hand scores at the latest follow-up between the 2 groups (P = 0.026). There was no difference in external rotation or mean length of follow-up between the 2 groups (P > 0.05). CONCLUSIONS:This study demonstrates the negative effects of ON after open reduction and internal fixation of proximal humerus fractures. Those who develop ON have poorer functional and clinical outcomes as compared with patients without ON. Consequently, the development of ON can be used as a predictor of poor outcomes. LEVEL OF EVIDENCE/METHODS:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background/UNASSIGNED:The study evaluates patient-reported outcomes in revision shoulder arthroplasty (RevSA) according to etiology. Methods/UNASSIGNED:Twenty-three consecutive RevSA (minimum 2-year follow-up) were retrospectively reviewed. Patient-reported outcome (PRO) scores and range of motion were compared by the type of revision procedure and indication. Results/UNASSIGNED:EQ5D-QOL, VAS-pain, ASES, and forward elevation improved after RevSA. The infection group had least improvements. Revision to a reverse total shoulder arthroplasty (RTSA) demonstrated the most improvement in VAS-pain, forward elevation, and ASES. Conclusions/UNASSIGNED:Revision to RTSA significantly improved PRO scores compared to hemi- or total shoulder arthroplasty. RevSA for infection demonstrated the least improvement in outcomes.

Introduction: Chlorhexidine gluconate (CHX) is widely used as a preoperative surgical skin-preparation solution and intra-wound irrigation agent, with excellent efficacy against wide variety of bacteria. The cytotoxic effect of CHX on local proliferating cells following orthopaedic procedures is largely undescribed. Our aim was to investigate the in vitro effects of CHX on primary fibroblasts, myoblasts, and osteoblasts. Methods: Cells were exposed to CHX dilutions (0%, 0.002%, 0.02%, 0.2%, and 2%) for either a 1, 2, or 3-minute duration. Cell survival was measured using a cytotoxicity assay (Cell Counting Kit-8). Cell migration was measured using a scratch assay: a "scratch" was made in a cell monolayer following CHX exposure, and time to closure of the scratch was measured. Results: All cells exposed to CHX dilutions of ≥ 0.02% for any exposure duration had cell survival rates of less than 6% relative to untreated controls (p < 0.001). Cells exposed to CHX dilution of 0.002% all had significantly lower survival rates relative to control (p < 0.01) with the exception of 1-minute exposure to fibroblasts, which showed 96.4% cell survival (p = 0.78). Scratch defect closure was seen in < 24 hours in all control conditions. However, cells exposed to CHX dilutions ≥ 0.02% had scratch defects that remained open indefinitely. Conclusions: The clinically used concentration of CHX (2%) permanently halts cell migration and significantly reduces survival of in vitro fibroblasts, myoblasts, and osteoblasts. Further in vivo studies are required to examine and optimize CHX safety and efficacy when applied near open incisions or intra-wound application.

Health-care reform, market competition, cost containment, and pressure for productivity have dramatically impacted the practice of orthopaedic surgery and academic surgical training. Orthopaedic leaders and training programs are striving to identify and solve these contemporary challenges. Herein, we focus on 4 areas that currently pose important challenges to modern orthopaedic surgical departments and academic hospital systems, including the demanding and evolving skill sets that are required of physician leaders, the effects of the changing medical-legal environment on academic medicine, the impact of increased clinical productivity emphasis on surgical education, and departmental leadership transitions.

Introduction: Aseptic glenoid loosening remains a long-term complication of total shoulder arthroplasty (TSA). To improve long-term fixation and decrease the risk of aseptic loosening, glenoid components with hybrid fixation, consisting of a large metal ingrowth central peg and cemented peripheral pegs, have been developed. The purpose of this prospective study is to determine the clinical and radiographic outcomes of a hybrid cage glenoid component compared to an age and gender matched polyethylene (PE) peg glenoid component with a minimum tow year follow-up. Methods: Three hundred and seventy-two patients with a mean age of 65 years were treated with a TSA for osteoarthritis by 7 sur-geons using either a cemented pegged glenoid or a hybrid fixation cage glenoid. 186 patients who received a cage glenoid (94 female and 92 males) were matched for sex and age with 186 patients who received a peg glenoid. The patients were scored preoperatively and at latest follow-up using the SST, UCLA, ASES, Constant, and SPADI metrics; active abduction, forward flexion, and active and passive external rotation were also measured. The average follow-up for all patients was 32 months (cage 31 months; peg 33 months). A St-udent's two-tailed, unpaired t-test was used to identify differences in preoperative, postoperative, and pre-to-post-operative improve-ments in results, where P <.05 denoted a significant difference. IRB approval was obtained at each institution. Results: All patients demonstrated significant improvements in pain and function following TSA with a cage or peg glenoid (P <.0001). For the cage prosthesis, ASES scores improved from 38 to 89, Constant scores from 40 to 76 (P <.0001). Significant improvements were also seen in the SST, UCLA and SPADI scores (P <.001). For the peg glenoid, ASES scores improved from 34 to 81, Constant scores from 36 to 69 (P <.0001), and significant improvements were also seen in the SST, UCLA and SPADI scores (P <.0001). Active forward flexion for a cage glenoid improved from 103degree to 151degree and active external rotation from 24degree to 54degree. Active forward flexion for a peg prosthesis improved from 93degree to 141degree and active external rotation from 18degree to 49degree (all P <.0001). Cemented peg glenoids were noted to have significantly lower preoperative ab-duction, active forward flexion and external rotation measurements (but not clinically meaningful differences) and there were significant differences in the preoperative scoring metrics between the two groups. Postoperatively, the cage prosthesis was significantly higher for all 5 scoring metrics, and significantly better in active forward flexion and external rotation, though unlikely clinically significant. Cage patients had significantly less blood loss than peg patients (mean 224 cc vs 268 cc; P =.0006). Radiographic data was available for 65% of cases. Radiolucent lines (RLL) were noted in 10% of cage glenoid patients and 28% of peg patients (P =.0003). The average RLL score was also significantly less in the cage group compared to the peg patients (.24 vs.51, P =.02). There were 2 revisions in the cage group and 6 in the peg group. The complication rate was 3.2% in the cage glenoid cohort and 8.6% in the peg cohort (P =.028). Discussion: Similar or better clinical outcomes were found at a minimum two years follow-up comparing a hybrid cage glenoid prosthesis with a cemented peg glenoid. Short-term results demon-strate statistically significant clinical improvements in both groups. Radiographically, there was a highly significant decrease in the incidence of RLL and average RLL grade following implantation of a cage glenoid relative to cemented peg glenoid, with an almost 3 times reduction in the appearance of RLL. Less blood loss was seen due to the decreased operative time. Despite widespread use of hybrid glenoids, there is little clinical data demonstrating any differences. This is the largest series to date and the first to demonstrate a decrease in the incidence of radiolucent lines following implantation of a hybrid cage glenoid component. Additional and longer-term follow-up is needed to confirm these early outcomes

BACKGROUND:Achieving glenoid fixation with anterior bone loss can be challenging. Limited guidelines have been established for critical defect sizes that can be treated without supplemental bone graft when performing reverse shoulder arthroplasty. METHODS:We quantified the impact of two sizes of anterior glenoid defects on glenoid baseplate fixation in a composite scapula using the ASTM F 2028-14 reverse shoulder glenoid loosening test method. RESULTS:All glenoid baseplates remained well-fixed after cyclic loading in composite scapula without a defect and in scapula with an 8.5 mm anterior glenoid defect; however, one of seven baseplates loosened in a scapula with a 12.5 mm defect. No difference was observed between pre- and post-cyclic baseplate displacements in scapula with 8.5 mm or 12.5 mm defects or in the control group scapula. However, baseplate displacement in scapula with 12.5 mm anterior defects was significantly greater after cyclic loading than that of baseplates in 8.5 mm defects (superior-inferior displacement, p = 0.0004; anterior-posterior displacement, p < 0.0001), where baseplate displacement in 8.5 mm (superior- inferior displacement, p = 0.0003; anterior-posterior displacement, p = 0.0014) and 12.5 mm (superior-inferior displacement, p < 0.0001; anterior-posterior displacement, p < 0.0001) defects after cyclic loading was significantly greater than that of baseplates in scapula without a defect. DISCUSSION/CONCLUSIONS:Adequate and stable fixation can be achieved in scapula with anterior glenoid defects of at least 8.5 mm in this biomechanical model using an established testing methodology; however, supplemental bone grafting should be utilized for anterior glenoid defects of 12.5 mm and larger using the reverse shoulder prosthesis tested in this study.

Neuropathic arthropathy, also known as Charcot arthropathy, is a degenerative disorder most commonly characterized by rapid destruction of the joint with extensive involvement of the bone and soft tissue. The underlying pathophysiology is thought to be due to loss of nociception (pain sensation), most frequently caused by diabetes mellitus, syphilitic myelopathy, or syringomyelia. A neuropathic shoulder is rare, with historic case series forming the bulk of the literature. The purpose of this review is to better understand the pathogenesis, clinical presentation, and management of neuropathic arthropathy of the glenohumeral joint. It should be stressed that the identification and management of the underlying etiology is paramount if the disease process is to be positively impacted. Although the mainstay of orthopedic management is non-surgical, little evidence exists to support the use of any specific therapeutic intervention. Recent literature suggests surgical reconstruction may be considered in very select patients.