Factors associated with functional improvement after posteriorly augmented total shoulder arthroplasty.

BACKGROUND: Posteriorly augmented glenoid components in anatomic total shoulder arthroplasty (TSA) address posterior glenoid bone loss with inconsistent results. The purpose of this study was to identify preoperative and postoperative factors that impact range of motion (ROM) and function after augmented TSA in patients with type B2 or B3 glenoid morphology. METHODS: This was a retrospective review of all patients who underwent TSA with a step-type augmentation performed by a single surgeon between 2009 and 2018. Patients with Walch type B2 or B3 glenoids were included. Outcomes included forward elevation (FE), external rotation (ER), internal rotation (IR), Single Assessment Numeric Evaluation (SANE) score, and visual analog scale pain score. Preoperative imaging was reviewed to assess glenoid retroversion and posterior humeral head subluxation relative to the scapular body and midglenoid face. Postoperative measurements included glenoid retroversion, subluxation relative to the scapular body, subluxation relative to the central glenoid peg, and center-peg osteolysis. Measurements were performed by investigators blinded to ROM and functional outcome scores. RESULTS: Fifty patients (mean age, 68.1 ± 8.0 years) with a mean follow-up period of 42.0 months (range, 24-106 months) were included. Glenoid morphology included type B2 glenoids in 41 patients and type B3 glenoids in 9. One patient had center-peg osteolysis, and 1 patient had glenoid component loosening. Average preoperative FE, ER, and IR were 110°, 21°, and S1, respectively. Average postoperative FE, ER, and IR were 155°, 42°, and L1, respectively. The mean postoperative visual analog scale score was 0.5 ± 0.8, and the mean SANE score was 94.5 ± 5.6. Type B3 glenoids were associated with better postoperative IR compared with type B2 glenoids (T10 vs. L1, P = .024), with no other differences in ROM between the glenoid types. Preoperative glenoid retroversion did not significantly impact postoperative ROM. Postoperative glenoid component retroversion and residual posterior subluxation relative to the scapular body or glenoid face did not correlate with ROM in any plane. However, posterior subluxation relative to the glenoid face was moderately associated with lower SANE scores (r = -0.448, P = .006). CONCLUSION: Patients achieved excellent functional outcomes and pain improvement after TSA with an augmented glenoid component. Postoperative ROM and function showed no clinically important associations with preoperative or postoperative glenoid retroversion or humeral head subluxation in our cohort of posteriorly augmented TSAs, except for worse functional scores with increased humeral head subluxation in relation to the glenoid surface.

Mid- to long-term outcomes of augmented and nonaugmented anatomic shoulder arthroplasty in Walch B3 glenoids.

BACKGROUND: In cases of severe osteoarthritis, posterior glenoid wear leads to acquired retroversion of the glenoid. Surgical treatment of glenoids with acquired retroversion and posterior humeral subluxation with anatomic total shoulder arthroplasty (aTSA) is controversial. The purpose of this study was to determine mid- to long-term outcomes and reoperation rates of augmented and nonaugmented aTSA for treatment of glenohumeral osteoarthritis with Walch B3 glenoid deformity. METHODS: This observational cohort study reviewed patients with a Walch B3 glenoid undergoing aTSA at a single institution between 2007 and 2014. Patients were contacted to complete updated patient-reported outcome measures at a minimum of 6 years postoperatively. Outcome measures collected included the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score and Single Alpha Numeric Evaluation (SANE) score. Secondary outcomes included any additional surgery on the operative shoulder, patient satisfaction, and willingness to undergo aTSA again. RESULTS: Thirty-nine patients met inclusion criteria, and thirty-five (89.7%) were able to be contacted for final outcomes evaluation. Mean follow-up was 8.7 years (range 6-13) after surgery. Sixteen patients were treated with an augmented glenoid component, and 19 patients were treated with a standard glenoid component. Of those with standard components, all were partially corrected with asymmetric reaming. At final follow-up, there were no statistically significant differences between those with augmented and standard glenoid components for mean ASES score (93.3 vs. 85.7, P = .217), ASES pain score (47.2 vs. 41.6, P = .161), SANE score (87.8 vs. 86.0, P = .692), and percentage patient satisfaction (95.6% vs. 96.8%, P = .735), forward elevation (148° vs. 149°, P = .852), or external rotation (36° vs. 39°, P = .202). No patient in either group had undergone revision surgery of the operative shoulder over the study period and all patients stated that they would undergo the same surgery again. DISCUSSION: Both augmented and standard aTSA can provide satisfactory and sustained improvements in patient-reported outcomes in patients with acquired glenoid retroversion due to glenohumeral osteoarthritis. Despite a trend toward alternative treatment options, anatomic shoulder arthroplasty should remain a surgical consideration even in the setting of a Walch B3 glenoid deformity.

Early postoperative complications after Latarjet procedure: a single-institution experience over 10 years.

BACKGROUND: The Latarjet procedure is an effective procedure for the treatment of anterior glenohumeral joint instability; however, the complications are concerning. The purpose of this study was to review a single institution's experience with the Latarjet procedure for recurrent anterior glenohumeral instability specifically focusing on early complications. METHODS: This was a retrospective review of all Latarjet procedures performed at a single institution from August 2008 to July 2018. The 90-day complication rate and associated risk factors for all complications and graft failure were recorded. Postoperative radiographs were reviewed for coracoid graft position and screw divergence. RESULTS: During the study period, 190 Latarjet procedures were performed with 90-day follow-up. The average age was 28.7 ± 11.3 years, male patients comprised 84.2% of the population, and 62.6% of patients had undergone a prior stabilization procedure. We observed 15 complications, for a 90-day complication rate of 9.0%; of the patients, 8 (4.2%) underwent reoperations. Graft or hardware failure occurred in 9 patients (4.7%) with loosened or broken screws, and 6 required reoperations (revision Latarjet procedure in 4, distal tibia allograft in 1, and iliac crest autograft in 1). Fixation with only 1 screw (P < .001) and an increased screw divergence angle (37° ± 8° vs. 24° ± 11°, P = .0257) were statistically associated with graft failure, whereas the use of cannulated screws (P = .487) was not. There were 6 nerve injuries (3.2%), including 2 combined axillary and suprascapular nerve injuries, 1 musculocutaneous nerve injury, 1 brachial plexopathy, 1 peripheral sensory nerve deficit (likely axillary), and 1 sensory plexopathy. Suprascapular nerve injury at the spinoglenoid notch was associated with a longer superior screw (41.0 ± 1.4 mm vs. 33.5 ± 3.5 mm, P = .035) and increased screw divergence angle (40° ± 6° vs. 24° ± 11°, P = .0197). The coracoid graft was correctly positioned in the axial plane in 71% of cases and in the coronal plane in 73% of cases. CONCLUSION: The Latarjet procedure is a procedure that can reliably restore shoulder stability; however, graft- and nerve-related complications are relatively common. Two-thirds of the graft failures required reoperations, and half of the nerve injuries in this study led to residual symptoms. Fixation with only 1 screw and an increased screw divergence angle were significant predictors of graft failure. Suprascapular nerve injury at the spinoglenoid notch was associated with an increased screw divergence angle and longer superior screw.

The effect of an orthopedic specialty hospital on operating room efficiency in shoulder arthroplasty.

BACKGROUND: Operating room (OR) time is a major cost to the health care system. Therefore, increasing OR efficiency to save time may be a cost-saving tool. This study analyzed OR efficiency in shoulder arthroplasty at an orthopedic specialty hospital (OSH) and a tertiary referral center (TRC). METHODS: All primary shoulder arthroplasties performed at our OSH and TRC were identified (2013-2015). Manually matched cohorts from the OSH and TRC were compared for OR times. Three times (minutes) were recorded: anesthesia preparation time (APT; patient in room to skin incision), surgical time (ST; skin incision to skin closed), conclusion time (CT; skin closed to patient out of room). RESULTS: There were 136 primary shoulder arthroplasties performed at the OSH and matched with 136 at the TRC. OSH and TRC patients were similar in age (P = .95), body mass index (P = .97), Charlson Comorbidity Index (P = 1.000), sex (P = 1.000), procedure (P = 1.000), insurance status (P = .714), discharge destination (P = .287), and diagnoses (P = .354). These matched populations had similar ST (OSH: 110.0 ± 26.6 minutes, TRC: 113.4 ± 28.7 minutes; P = .307). APT (39.2 ± 8.0 minutes) and CT (7.6 ± 3.8 minutes) were shorter in the OSH patients than APT (46.3 ± 8.8 minutes; P < .001) and CT (11.2 ± 4.7 minutes; P < .001) in TRC patients. Total nonoperative time (sum of APT and CT) at the OSH (46.8 ± 8.9 minutes) was shorter than at the TRC (57.5 ± 10.4 minutes; P < .001). CONCLUSIONS: Despite similar patient populations and case complexity, the OR efficiency at an OSH was superior to a TRC. Further analysis is needed to determine the financial implications of this superior OR efficiency.

An analysis of surgical and nonsurgical operating room times in high-volume shoulder arthroplasty.

BACKGROUND: A significant portion of operating room time in shoulder arthroplasty is devoted to nonsurgical tasks. To maximize efficiency and to increase access to care, it is important to accurately quantify surgical and nonsurgical time for shoulder arthroplasty. This study aimed to evaluate surgical vs. nonsurgical time and to assess the viability of using a 1-surgeon, 2-operating room model. METHODS: An institutional database was used to identify all primary and revision shoulder arthroplasty cases from February 2011 through December 2013. Time intervals were analyzed, including anesthesia and positioning time, surgical time, conclusion time, and turnover time. RESULTS: We identified 1062 shoulder arthroplasties. The average anesthesia and positioning time was 48.2 ± 11.7 minutes, surgical time was 122.7 ± 36.4 minutes, and conclusion time was 10.5 ± 7.0 minutes. Average turnover time at our institution was 40 minutes. An average of 58.8 ± 13.8 minutes (33.2%) of the patient's time in the operating room was not surgical. A 1-room surgical model, with each case following the next, would allow 3 arthroplasties to be performed in a 10-hour surgical day. A 2-room model would allow 4 cases to be performed in a 9-hour surgical day or 5 in an 11-hour day. In this 2-room model, there would be no time in which the surgeon is absent for any surgical portion of the case. CONCLUSION: For a high-volume shoulder arthroplasty practice, a 2-room model leads to greater efficiency and patient access to care without sacrificing the surgeon's presence during surgical portions of the case.

Is Arthroscopic Latarjet a Cost-Effective Procedure? A Decision Analysis.

Objectives: Arthroscopic Latarjet for glenohumeral stabilization has emerged as an alternative to the open approach; however, the evidence to date has questioned if this technique delivers improved outcomes. This analysis provides an assessment of the cost and utility associated with arthroscopic versus open Latarjet. Methods: The cost-effectiveness of Latarjet stabilization was modeled over a ten-year period. Institutional cases were reviewed for equipment utilization. Cost data from ambulatory surgical centers was obtained for each piece of equipment used intraoperatively. Based upon prior analyses, the operating room cost was assigned a value of $36.14 per minute. To determine effectiveness, a utility score was derived based upon prior analysis of shoulder stabilization using the EuroQol (EQ) 5D. For reoperations, a utility score of 0.01 was assigned for a single year for revision surgeries for instability and 0.5 for minor procedures. Probability of surgical outcomes and operative time for arthroscopic and open Latarjet were taken from prior studies comparing outcomes of these procedures. Decision-tree analysis utilizing these values was performed. Results: Based upon equipment and operating room costs, arthroscopic Latarjet was found to cost $2,796.87 more than the equivalent open procedure. Analysis of the utility of these procedures were 1.330 and 1.338 quality adjusted life years obtained over the modeled period for arthroscopic versus open Latarjet, respectively. For arthroscopic Latarjet to be cost-equivalent to open Latarjet, surgical time would need to be reduced to 41.5 minutes or the surgical equipment would need to be provided at no expense, while maintaining the same success rates. Conclusion: With nearly identical utility scores favoring open surgery, the added cost associated with arthroscopic Latarjet cannot be supported with available cost and utility data. To provide value, additional benefits such as decreased post-operative narcotic utilization, decreased blood loss, or lower complications of the arthroscopic approach must be demonstrated.

Utilization of comorbidity indices to predict discharge destination and complications following total shoulder arthroplasty.

Background: Comorbidity indices can help identify patients at risk for postoperative complications. Purpose of this study was to compare different comorbidity indices to predict discharge destination and complications after shoulder arthroplasty. Methods: Retrospective review of institutional shoulder arthroplasty database of primary anatomic (TSA) and reverse (RSA) shoulder arthroplasties. Patient demographic information was collected in order to calculate Modified Frailty Index (mFI-5), Charlson Comorbidity Index (CCI), age adjusted CCI (age-CCI), and American Society of Anesthesiologists physical status classification system (ASA). Statistical analysis performed to analyze length of stay (LOS), discharge destination, and 90-day complications. Results: There were 1365 patients included with 672 TSA and 693 RSA patients. RSA patients were older and had higher CCI, age adjusted CCI, ASA, and mFI-5 (p < 0.001). RSA patients had longer lengths of stay (LOS), more likely to have an adverse discharge (p < 0.001), and higher reoperation rate (p = 0.003). Age-CCI was most predictive of adverse discharge (AUC 0.721, 95% CI 0.704-0.768). Discussion: Patients undergoing RSA had more medical comorbidities, experienced greater LOS, higher reoperation rate, and were more likely to have an adverse discharge. Age-CCI had the best ability to predict which patients were likely to require higher-level discharge planning.

Hematoma Following Shoulder Arthroplasty: Incidence, Management, and Outcomes.

Background: A paucity of data regarding the implications of postoperative hematoma formation on outcomes after shoulder arthroplasty exists. Previous studies on major joint arthroplasty have associated postoperative hematoma formation with high rates of prosthetic joint infection (PJI) and reoperation. Methods: A total of 6,421 shoulder arthroplasty cases were retrospectively reviewed from an institutional database (5,941 primary cases, 480 revision) between December 2008 and July 2017. Patients who developed a postoperative hematoma were identified through direct chart review. Cases with a history of shoulder infection treated with explant and antibiotic spacer placement were excluded. Demographics, surgical characteristics, treatment course, and outcomes were collected. Results: Hematoma occurred in 105 (1.6%; 105/6421) cases within the first three postoperative weeks and was more common following revision (3.3%; 16/480) compared to primary cases (1.5 %; 89/5941; P=0.002). Overall, postoperative shoulder hematoma was successfully managed with nonoperative treatment in 87% of cases via observation (62%, 62/105) and aspiration (25%, 26/105). A total of 14 patients (0.22%, 14/6421) underwent reoperation for hematoma. Eight patients (7.6%, 8/105) that required reoperation for hematoma were diagnosed with PJI. Conclusion: Postoperative hematoma is a complication of shoulder arthroplasty. While many postoperative hematomas can be managed without operative intervention, this analysis reiterates the association between hematoma formation and the development of PJI.

Profibrotic behavior of fibroblasts derived from patients that develop posttraumatic shoulder stiffness.

Background and Aims: Arthrofibrosis is a severe scarring condition characterized by joint stiffness and pain. Fundamental to developing arthrofibrotic scars is the accelerated production of procollagen I, a precursor of collagen I molecules that form fibrotic deposits in affected joints. The procollagen I production mechanism comprises numerous elements, including enzymes, protein chaperones, and growth factors. This study aimed to elucidate the differences in the production of vital elements of this mechanism in surgical patients who developed significant posttraumatic arthrofibrosis and those who did not. Methods: We studied a group of patients who underwent shoulder arthroscopic repair of the rotator cuff. Utilizing fibroblasts isolated from the patients' rotator intervals, we analyzed their responses to profibrotic stimulation with transforming growth factor ß1 (TGFß1). We compared TGFß1-dependent changes in the production of procollagen I. We studied auxiliary proteins, prolyl 4-hydroxylase (P4H), and heat shock protein 47 (HSP47), that control procollagen stability and folding. A group of other proteins involved in excessive scar formation, including connective tissue growth factor (CTGF), α smooth muscle actin (αSMA), and fibronectin, was also analyzed. Results: We observed robust TGFß1-dependent increases in the production of CTGF, HSP47, αSMA, procollagen I, and fibronectin in fibroblasts from both groups of patients. In contrast, TGFß1-dependent P4H production increased only in the stiff-shoulder-derived fibroblasts. Conclusion: Results suggest P4H may serve as an element of a mechanism that modulates the fibrotic response after rotator cuff injury.

Outcomes of chronic distal biceps reconstruction with tendon grafting: a matched comparison with primary repair.

BACKGROUND: The purpose of this analysis was to analyze outcomes of distal biceps reconstruction with soft tissue allograft in the setting of chronic, irreparable distal biceps ruptures. The outcomes of these cases were then compared with a matched cohort of distal biceps ruptures that were able to be repaired primarily. METHODS: Retrospective review of an institutional elbow surgery database was conducted. All cases of distal biceps repairs were identified by Common Procedural Terminology, ICD-9, and ICD-10 codes from January 2009 to March 2018. A direct review of operative reports was then conducted to identify which cases required allograft reconstruction. After identification of this population, a 2:1 manually matched cohort of patients who underwent primary repair was generated using age, gender, body mass index, and age-adjusted Charlson Comorbidity Index. Finally, the allograft reconstruction and matched primary repair cohorts were compared for reoperation, range of motion, and patient-reported outcomes scores. RESULTS: There were 46 male patients who underwent distal biceps reconstruction with allograft (14 Achilles tendon, 32 semitendinosus) and they were matched to 92 male patients that underwent primary distal biceps repair. Mean patient age (46.9 ± 10.3 vs. 47.0 ± 9.8 years, P = .95), BMI (31.3 ± 5.3 vs. 31.3 ± 4.8 kg/m2, P = .60), and Charlson Comorbidity Index (1.2 ± 1.1 vs. 1.3 ± 0.9, P = .64) were similar between allograft reconstruction and primary repair groups. Disability of the Arm, Shoulder and Hand score (7.4 ± 18.0 vs. 1.6 ± 4.1, P = .23), Mayo Elbow Performance Score (92.1 ± 19.7 vs. 97.3 ± 6.4, P = .36), and Oxford Elbow Score (43.4 ± 11.0 vs. 46.8 ± 3.2, P = .25) were not significantly different between groups at mean 5.1 years (range, 1.5-10.9 years) after surgery. There were 1 of 42 (2.2%) allograft patients who require revision compared with 3 of 92 (3.3%, P = .719) in the primary repair group. In addition, one primary repair required reoperation for scar tissue excision and lateral antebrachial cutaneous neurolysis. Final range of motion data (twelve-week follow-up) for the allograft reconstruction group was similar to primary repair group in flexion (136.1° ± 5.3° vs. 135.9° ± 2.7°, P = .81), extension (0.8° ± 2.9° vs. 0.4° ± 1.7°, P = .53), pronation (78.0° ± 9.0° vs. 76.4° ± 15.4°, P = .50), supination (77.4° ± 10.7° vs. 77.5° ± 11.9°, P = .96). CONCLUSION: Patients who underwent distal biceps reconstruction with a graft had similar failure rates, reoperation rates, final range of motion, and patient-reported outcomes scores as those treated without a graft. Patients can be consulted that direct repair in the acute setting is preferred; however, even in the setting of a distal biceps reconstruction with graft augmentation, they can expect low complications and good functional results.

Humeral Shaft Fractures: Surgical versus Nonsurgical Management in Workers' Compensation.

BACKGROUND: The optimal surgical indications for humeral shaft fractures in the working population remain uncertain. This study investigates the impact of surgical fixation on return to duty, union, and complications in workers' compensation patients with humeral shaft fractures. METHODS: All workers' compensation patients with humeral shaft fractures managed at a single institution between 2007 and 2017 were identified. Manual chart and radiographic review was performed to identify etiology of injury, type of work, time until return to duty, length of physical therapy, complications, and time to fracture union. RESULTS: There were 39 humeral shaft fractures in workers' compensation patients managed at our institution (25 surgical; 64.1%). There was no difference in the return to light (106.1 versus 60.4 days; P=0.20) or full (140.1 vs. 139.9 days; P=0.99) duty for surgical versus nonsurgical treatment, respectively. There was no difference in the length of physical therapy (132.6 versus 106.3 days; P=0.15) or time to maximum medical improvement (174.3 vs. 198.8 days; P=0.25) for surgical versus nonsurgical treatment, respectively. Three patients returned to the operating room in the surgical group. Nonunion was observed in two surgical cases (8.0%) and one case (7.1%) of nonsurgical management. CONCLUSION: This study did not identify an advantage for faster return to work after surgical management of humeral shaft fractures in workers' compensation patients. Though one of the perceived advantages of surgical fixation is a quicker return to physical activity, there may be other variables in this patient population that influence the timing of return to work.

Improvement of Outcomes During the First Two Years Following Total Ankle Arthroplasty.

BACKGROUND: Many studies of total ankle arthroplasty (TAA) have focused on the range of motion and functional outcomes at the time of intermediate-term follow-up. The purpose of our study was to analyze the progression of ankle hindfoot range of motion and patient-reported measures through the first 2 years following TAA. METHODS: The charts of 134 patients who had been treated with a TAA by a single surgeon were retrospectively reviewed, and 107 (109 TAAs) were included in the study. The overall range of motion in the sagittal plane was measured as the change in the position of the tibia relative to the floor on dedicated weight-bearing lateral radiographs made with the ankle in maximum plantar flexion and dorsiflexion preoperatively and at 3 months, 6 months, 1 year, and 2 years postoperatively. In addition, patients completed a visual analogue scale (VAS) for pain, the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) and Sports Subscales, and the Short Form-12 (SF-12) Physical (PCS) and Mental (MCS) Component Summary scores at each time interval. RESULTS: The mean overall range of motion in the sagittal plane was 20.7° preoperatively and improved to 28.3°, 34.3°, 33.3°, and 33.3° at 3 months, 6 months, 1 year, and 2 years, respectively (p < 0.001). At each postoperative time point, the median VAS score was improved (p < 0.001) compared with the preoperative VAS score. Similarly, the FAAM and SF-12 scores were improved, compared with the preoperative score, at 6 months and later (p < 0.001). An increased range of motion correlated with a lower VAS score preoperatively (ρ = -0.31, p = 0.035) and at 1 year (ρ = -0.36, p = 0.003) postoperatively. An increased range of motion correlated with a higher FAAM ADL score at 3 months (ρ = 0.50, p = 0.012), 1 year (ρ = 0.26, p = 0.040), and 2 years (ρ = 0.39, p = 0.003) postoperatively. CONCLUSIONS: Patients who underwent TAA had improvement, compared with preoperatively, in the overall sagittal plane range of motion up to 6 months and maintained improvement in pain and function scores up to 2 years. Pain scores remained improved throughout the 2-year follow-up period. A better range of motion was correlated with less pain as measured with the VAS. An increased range of motion postoperatively was correlated with better function as measured with the FAAM. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Antibiotic Spacers in Shoulder Arthroplasty: Comparison of Stemmed and Stemless Implants.

BACKGROUND: Antibiotic spacers in shoulder periprosthetic joint infection deliver antibiotics locally and provide temporary stability. The purpose of this study was to evaluate differences between stemmed and stemless spacers. METHODS: All spacers placed from 2011 to 2013 were identified. Stemless spacers were made by creating a spherical ball of cement placed in the joint space. Stemmed spacers had some portion in the humeral canal. Operative time, complications, reimplantation, reinfection, and range of motion were analyzed. RESULTS: There were 37 spacers placed: 22 were stemless and 15 were stemmed. The stemless spacer population was older (70.9 ± 7.8 years vs. 62.8 ± 8.4 years, p = 0.006). The groups had a similar percentage of each gender (stemless group, 45% male vs. stemmed group, 40% male; p = 0.742), body mass index (stemless group, 29.1 ± 6.4 kg/m2 vs. stemmed group, 31.5 ± 8.3 kg/m2; p = 0.354) and Charlson Comorbidity Index (stemless group, 4.2 ± 1.2 vs. stemmed group, 4.2 ± 1.7; p = 0.958). Operative time was similar (stemless group, 127.5 ± 37.1 minutes vs. stemmed group, 130.5 ± 39.4 minutes). Two stemless group patients had self-resolving radial nerve palsies. Within the stemless group, 15 of 22 (68.2%) underwent reimplantation with 14 of 15 having forward elevation of 109° ± 23°. Within the stemmed group, 12 of 15 (80.0%, p = 0.427) underwent reimplantation with 8 of 12 having forward elevation of 94° ± 43° (range, 30° to 150°; p = 0.300). Two stemmed group patients had axillary nerve palsies, one of which self-resolved but the other did not. One patient sustained dislocation of reverse shoulder arthroplasty after reimplantation. One stemless group patient required an open reduction and glenosphere exchange of dislocated reverse shoulder arthroplasty at 6 weeks after reimplantation. CONCLUSIONS: Stemmed and stemless spacers had similar clinical outcomes. When analyzing all antibiotic spacers, over 70% were converted to revision arthroplasties. The results of this study do not suggest superiority of either stemmed or stemless antibiotic spacers.