Modular baseplate augmentation: a simple and effective method for addressing eccentric glenoid wear.

BACKGROUND: Augmented baseplates can be effective at addressing eccentric glenoid wear in reverse total shoulder arthroplasty. However, these implants often come in a limited number of predetermined shapes that require additional reaming to ensure adequate glenoid seating. This typically involves complex instrumentation and can have a negative impact on implant stability. Modular baseplate augmentation based on intraoperative measurements may allow for more precise defect filling while preserving glenoid bone. The purpose of this investigation was to assess the stability of a novel ringed baseplate with modular augmentation in comparison with nonaugmented standard and ringed baseplate designs. METHODS: In this biomechanical study, baseplate micromotion was tested for 3 constructs according to the American Society for Testing and Materials guidelines. The constructs included a nonaugmented curved baseplate, a nonaugmented ringed baseplate, and a ringed baseplate with an 8-mm locking modular augmentation peg. The nonaugmented constructs were mounted flush onto polyurethane foam blocks, whereas the augmented baseplate was mounted on a polyurethane block with a simulated defect. Baseplate displacement was measured before and after 100,000 cycles of cyclic loading. RESULTS: Before cyclic loading, the nonaugmented and augmented ringed baseplates both demonstrated significantly less micromotion than the nonaugmented curved baseplate design (81.1 µm vs. 97.2 µm vs. 152.7 µm; P = .009). After cyclic loading, both ringed constructs continued to have significantly less micromotion than the curved design (105.5 µm vs. 103.2 µm vs. 136.6 µm; P < .001). The micromotion for both ringed constructs remained below the minimum threshold required for bony ingrowth (150 µm) at all time points. CONCLUSIONS: In the setting of a simulated glenoid defect, locked modular augmentation of a ringed baseplate does not result in increased baseplate micromotion when compared with full contact nonaugmented baseplates. This design offers a simple method for tailored baseplate augmentation that can match specific variations in glenoid anatomy, limiting the need for excessive reaming and ultimately optimizing the environment for long-term implant stability.

Effect of vitamin E-enhanced highly cross-linked polyethylene on wear rate and particle debris in anatomic total shoulder arthroplasty: a biomechanical comparison to ultrahigh-molecular-weight polyethylene.

BACKGROUND: Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. METHODS: Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. RESULTS: The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P < .05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P < .05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P < .05). CONCLUSIONS: A new anatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.

Anatomic shoulder arthroplasty with high side reaming versus reverse shoulder arthroplasty for eccentric glenoid wear patterns with an intact rotator cuff: comparing early versus midterm outcomes with minimum 7 years of follow-up.

BACKGROUND: Eccentric glenoid bone loss patterns (B- and C-type glenoid) pose a difficult challenge when performing shoulder arthroplasty. Anatomic total shoulder arthroplasty with preferential high-side reaming (ATSA + HSR) has been an accepted method to treat this problem. Reverse shoulder arthroplasty (RSA) has become an alternative method to manage these cases with eccentric glenoid wear. The purpose of this study was to compare the early 2-year outcomes with the midterm outcomes for patients who underwent ATSA + HSR vs. RSA for eccentric glenoid wear patterns with an intact rotator cuff. MATERIALS AND METHODS: From 2008 to 2014 there were 242 shoulder arthroplasties performed in the setting of eccentric glenoid wear patterns. Of that initial cohort 101 ATSA + HSR and 93 RSA had both 2-year and final follow-up with a minimum of 7 years from surgery. American Shoulder and Elbow Surgeons (ASES) scores, Simple Shoulder Test (SST), range of motion, patient satisfaction, and radiographs were evaluated for each cohort and contrasted at the 2-year follow-up point and last follow-up time point. RESULTS: The average follow-up in the ATSA + HSR cohort was 8.3 years compared with 7.8 years in the RSA cohort. At the 2-year follow-up point, the ATSA + HSR group had better average ASES scores (85 vs. 80 [P < .001]), SST scores (10 vs. 9.6 [P < .001]), forward elevation (162° vs. 151° [P < .001]), external rotation (47° vs. 42° [P < .001]), and internal rotation (IR) (80% full IR vs. 55% full IR [P < .001]). At the 2-year follow-up, 95% of the ATSA + HSR cohort were satisfied compared with 93% in the RSA cohort. At the final follow-up, the RSA group had better average ASES scores (80 vs. 77 [P < .001]) and SST scores (9.4 vs. 8 [P < .001]) and a similar forward elevation (152° vs. 149° [P = .025]). The ATSA + HSR had better external rotation (45° vs. 41° [P < .001]) and IR (74% full IR vs. 54% full IR [P = .005]). Patient satisfaction at the final follow-up had decreased to 82% in the ATSA + HSR group, compared with 95% satisfied in the RSA group. Of the initial ATSA + HSR cohort, 8% of patients had undergone revision compared with 2% in the RSA cohort. CONCLUSION: ATSA with HSR had better outcome scores and range of motion with a similar patient satisfaction rating to RSA at the 2-year point. Over time, the ATSA + HSR results deteriorated, and at the final midterm follow-up, the RSA group had more durable results with better outcome scores, a higher patient satisfaction rating, and a lower revision rate.

Consensus statement on the treatment of massive irreparable rotator cuff tears: a Delphi approach by the Neer Circle of the American Shoulder and Elbow Surgeons.

BACKGROUND: Management of massive irreparable rotator cuff tears (MIRCTs) remains controversial owing to variability in patient features and outcomes contributing to a lack of unanimity in treatment recommendations. The purpose of this study was to implement the Delphi process using experts from the Neer Circle of the American Shoulder and Elbow Surgeons to determine areas of consensus regarding treatment options for a variety of MIRCTs. METHODS: A panel of 120 shoulder surgeons were sent a survey regarding MIRCT treatments including arthroscopic débridement and partial cuff repair, graft augmentation, reverse shoulder arthroplasty (RSA), superior capsular reconstruction (SCR), and tendon transfer. An iterative Delphi process was then conducted with a first-round questionnaire consisting of 13 patient factors with the option for open-ended responses to identify important features influencing the treatment of MIRCTs. The second-round survey sought to determine the importance of patient factors related to the 6 included treatment options. A third-round survey asked participants to classify treatment options for 60 MIRCT patient scenarios as either preferred treatment, acceptable treatment, not acceptable/contraindicated, or unsure/no opinion. Patient scenarios were declared to achieve consensus for the preferred and not acceptable/contraindicated categories when at least 80% of the survey respondents agreed on a response, and a 90% threshold was required for the acceptable treatment category, defined by an acceptable treatment or preferred treatment response. RESULTS: Seventy-two members agreed to participate and were deemed to have the requisite expertise to contribute based on their survey responses regarding clinical practice and patient volume. There were 20 clinical scenarios that reached 90% consensus as an acceptable treatment, with RSA selected for 18 scenarios and arthroscopic débridement and/or partial repair selected for 2. RSA was selected as the singular preferred treatment option in 8 scenarios. Not acceptable/contraindicated treatment options reached consensus in 8 scenarios, of which, 4 related to SCR, 3 related to RSA, and 1 related to partial repair with graft augmentation. CONCLUSION: This Delphi process exhibited significant consensus regarding RSA as a preferred treatment strategy in older patients with pseudoparesis, an irreparable subscapularis, and dynamic instability. In addition, the process identified certain unacceptable treatments for MIRCTs such as SCR in older patients with pseudoparesis and an irreparable subscapularis or RSA in young patients with an intact or reparable subscapularis without pseudoparesis or dynamic instability. The publication of these scenarios and areas of consensus may serve as a useful guide for practitioners in the management of MIRCTs.

Randomized prospective evaluation of the use of tranexamic acid and effects on blood loss for proximal humeral fracture surgery.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic agent that has been used to reduce blood loss in orthopedic surgery. It has been shown to decrease blood loss in upper- and lower-extremity arthroplasty, as well as lower-extremity fracture surgery. The use of TXA for proximal humeral fracture surgery has yet to be evaluated. The purpose of this study was to examine the effects of TXA on blood loss in patients undergoing open reduction-internal fixation (ORIF) or arthroplasty for the treatment of proximal humeral fractures. MATERIALS AND METHODS: A total of 101 patients were randomized to receive either a single preoperative dose of intravenous TXA (53 patients) or a control dose of saline solution (48 patients) at the time of proximal humeral fracture surgery. On the basis of patient age and fracture pattern, ORIF was performed in 57 patients (30 TXA and 27 control patients) and reverse shoulder arthroplasty (RSA) was performed in the other 44 patients (23 TXA and 21 control patients). Intraoperative blood loss plus 24-hour drain output was used to calculate total blood loss for each procedure. The preoperative-to-postoperative change in hemoglobin level was also evaluated for each patient. Further stratification of blood loss and change in hemoglobin level based on procedure (ORIF or RSA) was performed as well. RESULTS: Compared with the control group, the TXA group had less average intraoperative blood loss (178 mL vs. 129 mL, P < .0001), less postoperative drain output (103 mL vs. 62 mL, P < .0001), and less total blood loss (280 mL vs. 188 mL, P < .0001). Compared with the control group, the TXA group had a smaller average preoperative-to-postoperative change in hemoglobin level (-2.6 g/dL vs. -1.5 g/dL, P < .0001). Further stratification based on procedure showed that among patients undergoing ORIF and patients undergoing RSA, those receiving TXA had less average total blood loss and a smaller decrease in hemoglobin level than the control group. No identifiable intraoperative or postoperative complications associated with the use of TXA occurred in any patient. CONCLUSION: TXA was effective in reducing total blood loss and led to a smaller preoperative-to-postoperative decrease in hemoglobin level compared with control in patients undergoing surgery for proximal humeral fractures. This effect was consistent in patients treated with either ORIF or arthroplasty as the surgical procedure. TXA can be used to decrease blood loss in the surgical treatment of proximal humeral fractures.

Total shoulder arthroplasty with minimum 5-year follow-up: does the presence of subchondral cysts in the glenoid increase risk of failure?

BACKGROUND: This study evaluated the effect of cystic changes in the glenoid on postoperative outcomes and implant survival after total shoulder arthroplasty (TSA). MATERIALS AND METHODS: From 2004 to 2012, 75 patients underwent TSA for primary osteoarthritis with minimum 5-year follow-up. Preoperative 3-dimensional models based on computed tomography imaging were created for all patients. A qualitative evaluation of cystic osteoarthritis was performed through survey grading by 3 fellowship-trained shoulder surgeons. The extent of cyst formation in the glenoid (no cysts, small, medium, or large) was assigned for every patient. In addition, quantitative evaluation was performed on 3-dimensional glenoid models. Functional outcomes, radiographic findings, and the need for revision were compared between group 1 (large and medium cysts) and group 2 (small and no cysts). RESULTS: Qualitative evaluation of cyst formation resulted in the following distribution: no cysts in 8 patients (11%), small cyst formation in 27 (36%), medium cysts in 19 (25%), and large cysts in 21 patients (28%; κ = 0.605). The difference in total cyst volume between group 1 and group 2 was significant (P = .004). The overall revision rate was 7% (5 of 75). All revised patients were in the groups with medium or large cysts. There were no statistical differences in American Shoulder and Elbow Surgeons (ASES) Standardized Shoulder Assessment scores or presence of radiographic loosening among the study groups. CONCLUSION: Qualitative computed tomography evaluation of cystic osteoarthritis correlates with quantitative analysis of cyst volume. Severe cyst formation portends a higher risk of failure at midterm follow-up. Cystic disease did not affect functional outcome or the presence of radiographic glenoid loosening.

Classification of instability after reverse shoulder arthroplasty guides surgical management and outcomes.

BACKGROUND: Revision of unstable reverse shoulder arthroplasty (RSA) remains a significant challenge. The purpose of this study was to determine the reliability of a new treatment-guiding classification for instability after RSA, to describe the clinical outcomes of patients stabilized operatively, and to identify those with higher risk of recurrence. METHODS: All patients undergoing revision for instability after RSA were identified at our institution. Demographic, clinical, radiographic, and intraoperative data were collected. A classification was developed using all identified causes of instability after RSA and allocating them to 1 of 3 defined treatment-guiding categories. Eight surgeons reviewed all data and applied the classification scheme to each case. Interobserver and intraobserver reliability was used to evaluate the classification scheme. Preoperative clinical outcomes were compared with final follow-up in stabilized shoulders. RESULTS: Forty-three revision cases in 34 patients met the inclusion for study. Five patients remained unstable after revision. Persistent instability most commonly occurred in persistent deltoid dysfunction and postoperative acromial fractures but also in 1 case of soft tissue impingement. Twenty-one patients remained stable at minimum 2 years of follow-up and had significant improvement of clinical outcome scores and range of motion. Reliability of the classification scheme showed substantial and almost perfect interobserver and intraobserver agreement among all the participants (κ = 0.699 and κ = 0.851, respectively). DISCUSSION: Instability after RSA can be successfully treated with revision surgery using the reliable treatment-guiding classification scheme presented herein. However, more understanding is needed for patients with greater risk of recurrent instability after revision surgery.

Evaluation of Factors Affecting Acute Postoperative Pain Levels After Arthroscopic Rotator Cuff Repair.

PURPOSE: To evaluate multiple preoperative and operative factors that may be predictive of and correlate with acute postoperative pain levels after arthroscopic rotator cuff repair. METHODS: One hundred eighty-one patients underwent arthroscopic rotator cuff surgery along with subacromial decompression and met the inclusion criteria for this study. Postoperative visual analog scale (VAS) scores were obtained on postoperative days 1, 7, and 90. Multivariate linear regression analysis was used to correlate postoperative VAS scores with multiple independent factors, including preoperative subjective pain tolerance, preoperative VAS score, preoperative narcotic use, sex, smoking status, number of suture anchors used, tear size, single- or double-row repair, and patient age. RESULTS: Preoperative subjective pain tolerance, notably those patients rating themselves as having an extremely high pain tolerance, was the most significant predictor of high VAS pain scores on both postoperative day 1 (P = .0001) and postoperative day 7 (P < .0001). Preoperative narcotic use was also significantly predictive (P = .010) of high pain scores on postoperative day 1 and day 7 (P = .019), along with nonsmokers (P = .008) and younger patients (P = .006) being predictive on day 7. There were no patient factors that were predictive of VAS scores 3 months postoperatively (P = .567). CONCLUSIONS: Preoperative subjective pain tolerance, notably those patients rating themselves as having an extremely high pain tolerance, was the strongest factor predicting high acute pain levels after arthroscopic rotator cuff surgery. Preoperative narcotic use, smokers, and younger patients were also predictive of higher pain levels during the first postoperative week. LEVEL OF EVIDENCE: Level IV, prognostic case series.

Partial rotator cuff repair and biceps tenotomy for the treatment of patients with massive cuff tears and retained overhead elevation: midterm outcomes with a minimum 5 years of follow-up.

BACKGROUND: A subset of patients with massive irreparable rotator cuff tears present with retained overhead elevation and pain as their primary complaint. Our aim was to evaluate the outcomes of partial arthroscopic rotator cuff repair with biceps tenotomy and to report the failure rate of this procedure for patients with >5 years of follow-up. METHODS: Thirty-four patients underwent partial rotator cuff repair and biceps tenotomy for treatment of a massive rotator cuff tear. Patients had preoperative active forward elevation >120° and no radiographic evidence of glenohumeral arthritis. Patients were followed up clinically and radiographically, and 28 patients had a minimum of 5 years of follow-up. Failure was defined as an American Shoulder and Elbow Surgeons score of <70, loss of active elevation >90°, or revision to reverse shoulder arthroplasty during the study period. RESULTS: Patients demonstrated improvements in average preoperative to postoperative American Shoulder and Elbow Surgeons scores (46.6 to 79.3 [P < .001]) and Simple Shoulder Test scores (5.7 to 9.1 [P < .001]) along with decrease in visual analog scale for pain scores (6.9 to 1.9 [P < .001]). No significant change in forward elevation (168° to 154° [P = .07]), external rotation (38° to 39° [P = 1.0]), or internal rotation (84% to 80% [P = 1.0]) was identified; 36% of patients had progression of the Hamada stage. The failure rate was 29%; 75% of patients were satisfied with their index procedure. CONCLUSION: Partial rotator cuff repair and biceps tenotomy for patients with massive irreparable rotator cuff tears with retained overhead elevation and pain as the primary complaint produced reasonable outcomes at midterm follow-up of at least 5 years.

Glenosphere dissociation after reverse shoulder arthroplasty.

BACKGROUND: Reverse shoulder arthroplasty (RSA) is gaining popularity for the treatment of debilitating shoulder disorders. Despite marked improvements in patient satisfaction and function, the RSA complication rate is high. Glenosphere dissociation has been reported and may result from multiple mechanisms. However, few RSA retrieval studies exist. METHODS: We reviewed our RSA database and identified patients with glenosphere dissociation between 1999 and 2013. Prosthesis type, glenosphere size, and contributing factors to dissociation were noted. Five retrieved implants were available for analysis, and evidence of wear or corrosion on the Morse taper was documented. Further, we biomechanically investigated improper Morse taper engagement that may occur intraoperatively as a potential cause of acute dissociation. RESULTS: Thirteen patients with glenosphere dissociation were identified (0.5 months to 7 years postoperatively). Glenosphere size distribution was as follows: 32 mm (n = 1), 36 mm (n = 4), 40 mm (n = 6), and 44 mm (n = 2). Incidence of dissociation was correlated to glenosphere size (P < .001). Taper damage was limited to fretting wear, and there was minimal evidence of taper corrosion. Biomechanically, improper taper engagement reduced the torsional capacity of the glenosphere-baseplate interface by 60% from 19.2 ± 1.0 N-m to 7.5 ± 1.5 N-m. CONCLUSION: We identified several mechanisms contributing to glenosphere dissociation after RSA, including trauma and improper taper engagement. Limited evidence of corrosive wear on the taper interface was identified. Although it is rare, the incidence of glenosphere dissociation was higher when 40- and 44-mm glenospheres were implanted compared with smaller glenospheres (32 and 36 mm), probably because of the larger exposed surface area for potential impingement.

Scapular fractures after reverse shoulder arthroplasty: evaluation of risk factors and the reliability of a proposed classification.

BACKGROUND: The aims were to determine the sensitivity of plain radiographs to detect scapular fractures after reverse shoulder arthroplasty (RSA), to test the reliability of a proposed classification, and to evaluate risk factors. MATERIALS AND METHODS: We matched 53 patients with scapular fractures after RSA to 212 control patients. Clinical risk factors were assessed by correlating comorbidities. Independent observers reviewed radiographs to assess fracture detection accuracy and test the reliability of a proposed classification. Radiographic risks were evaluated by measuring acromial thickness, acromial tilt, glenoid-to-tuberosity distance, and acromion-to-tuberosity (AT) distance. RESULTS: Independent reviewers accurately diagnosed 78.8% of fractures and 97.4% of controls with good inter-rater reliability (κ = 0.782) and excellent intrarater reliability (κ = 0.862). Inter-rater reliability of the classification was moderate (κ = 0.422). Osteoporosis significantly increased the risk of fracture (odds ratio, 1.97; 95% confidence interval, 1.00-3.91); however, no difference was found for other comorbidities or between preoperative and postoperative radiographic parameters. A significant difference occurred between groups from the postoperative radiographs to the most recent radiographs for AT distance (0.4 ± 5.5 mm for control group and 8.3 ± 7.6 mm for fracture group, P < .001) and acromial tilt (1.8° ± 6.3° for control group and 14° ± 15° for fracture group, P < .001). Of 16 scapular spine fractures, 14 occurred from a screw tip; however, screw orientation and length were not different between groups. CONCLUSION: Osteoporosis is a significant risk factor for scapular fractures after RSA. The current classification has only moderate reliability, suggesting that an alternative classification method is needed. Decreasing AT distance and increasing acromial tilt on consecutive radiographs may improve fracture detection. Advanced imaging may be needed to confirm the diagnosis. Whereas most scapular spine fractures occurred from a screw, the surgical technique did not increase the relative risk.

Prospective evaluation of postoperative compliance and outcomes after rotator cuff repair in patients with and without workers' compensation claims.

BACKGROUND: This study prospectively evaluated compliance and outcomes after rotator cuff repair in patients with and without Workers' Compensation claims. MATERIALS AND METHODS: From December 2007 to January 2010, 42 consecutive patients with Workers' Compensation claims (Work Comp group), and 50 consecutive patients without a Workers' Compensation claim (non-Work Comp group) underwent arthroscopic rotator cuff repair and were enrolled in this study. Compliance with a postoperative protocol of shoulder immobilization and physical therapy was documented. Patients were monitored clinically for a minimum of 12 months. RESULTS: Noncompliance with protocol was documented in 22 of 42 patients (52%) in the Work Comp group compared with 2 of 50 (4%) in the non-Work Comp group (P < .001). The Work Comp group had less improvement in preoperative to postoperative outcome scores for the American Shoulder and Elbow Surgeons (ASES) score (40.4 to 60.1), Simple Shoulder Test (SST) score (3.9 to 6.0) and visual analog scale (VAS) for pain (7.0 to 3.5) compared with the non-Work Comp group (ASES, 41.7 to 89.2; SST, 4.3 to 10.7; VAS, 6.2 to 0.35; P < .0001). The compliant Work Comp patients had more favorable results in final outcome scores (ASES, 73.1; SST, 7.9; VAS, 1.5) than noncompliant Work Comp patients (ASES, 48.4; SST, 4.3; VAS, 5.3; P < .0001). CONCLUSIONS: Patients with Workers' Compensation claims demonstrated a high rate of postoperative noncompliance (52%) compared with patients without Workers' Compensation claims (4%) after rotator cuff repair. Those Workers' Compensation patients who had no evidence of noncompliance had significant improvements and more favorable outcomes than the noncompliant Workers' Compensation patients.

Prospective randomized study of arthroscopic rotator cuff repair using an early versus delayed postoperative physical therapy protocol.

BACKGROUND: This study evaluated patient outcomes and rotator cuff healing after arthroscopic rotator cuff repair using a postoperative physical therapy protocol with early passive motion compared with a delayed protocol that limited early passive motion. MATERIALS AND METHODS: The study enrolled 68 patients (average age, 63.2 years) who met inclusion criteria. All patients had a full-thickness crescent-shaped tear of the supraspinatus that was repaired using a transosseous equivalent suture-bridge technique along with subacromial decompression. In the early group, 33 patients were randomized to passive elevation and rotation that began at postoperative day 2. In the delayed group, 35 patients began the same protocol at 6 weeks. Patients were monitored clinically for a minimum of 12 months, and rotator cuff healing was assessed using ultrasound imaging. RESULTS: Both groups had similar improvements in preoperative to postoperative American Shoulder and Elbow Surgeons scores (early group: 43.9 to 91.9, P < .0001; delayed group: 41.0 to 92.8, P < .0001) and Simple Shoulder Test scores (early group: 5.5 to 11.1, P < .0001; delayed group: 5.1 to 11.1, P < .0001). There were no significant differences in patient satisfaction, rotator cuff healing, or range of motion between the early and delayed groups. CONCLUSIONS: Patients in the early group and delayed group both demonstrated very similar outcomes and range of motion at 1 year. There was a slightly higher rotator cuff healing rate in the delayed passive range of motion group compared with the early passive range of motion group (91% vs 85%).

Torsional stability of modular and non-modular reverse shoulder humeral components in a proximal humeral bone loss model.

HYPOTHESIS/BACKGROUND: Patients who are treated with reverse shoulder arthroplasty in the setting of proximal humeral bone loss present a technical challenge for humeral component fixation. The purpose of this study was to determine the effect of proximal humeral bone loss on fixation of reverse shoulder humeral implants. MATERIALS AND METHODS: Three reverse humeral designs (two modular and one monobloc) were cemented into twenty-four Sawbones humeri prepared to simulate intact and proximal humeral bone loss. Torque was applied to the humerus for 1,000 cycles in increments of 2.5 N-m to 25 N-m. Rotational micromotion of the implant was measured. RESULTS: There was a significant decrease in rotational micromotion in the intact constructs when compared with the bone loss constructs (we found P < .01 when looking at torsion levels of 5 to 17.5 N-m). In the intact humerus, 10 of 12 implant constructs survived testing. The 2 that failed were modular implants. In the bone loss setting, 7 of 12 implant constructs survived testing. The 5 that failed were also modular implants. CONCLUSIONS: This is the first investigation on humeral component fixation in reverse shoulder arthroplasty. The proximal humerus adds stability to the fixation of a cemented humeral implant. Modular components in the presence of proximal humeral bone loss may be at increased risk of mechanical failure. Conversely, non-modular cemented humeral components can withstand greater loads before failure.

Revision reverse shoulder arthroplasty for glenoid baseplate failure after primary reverse shoulder arthroplasty.

BACKGROUND: The aim of this study is to document a single surgeon's experience performing revision reverse shoulder arthroplasty after baseplate failure. METHODS: Revision reverse shoulder arthroplasty (RSA) for mechanical failure of the glenoid baseplate after RSA was performed in 14 patients. Clinical and radiographic data were collected preoperatively, prior to baseplate failure, after baseplate failure, and at latest follow-up after revision (average, 33 months). RESULTS: When comparing the pre-operative values to post-revision, ASES, forward elevation, and abduction were significantly improved. There was no significant difference in any of the outcome measures when comparing the prefailure data to the post-revision data. The post-revision prosthesis-scapular neck angle (PSNA) showed a significant increase in inferior tilt of the baseplate when compared to pre-failure PSNA (P < .001). Two patients (14%) required a second revision RSA for glenoid baseplate failure (1) and dislocation (1); 1 additional patient developed a postoperative hematoma which resolved without surgery. CONCLUSION: Revision RSA for the treatment of glenoid baseplate mechanical failure can restore pain relief and function to the levels gained after the index RSA.

Young patients with shoulder chondrolysis following arthroscopic shoulder surgery treated with total shoulder arthroplasty.

Chondrolysis following shoulder arthroscopy is a devastating complication, often seen in young patients. After nonoperative measures have been exhausted, there are few treatment options available that reliably improve pain and function. The purpose of this study is to examine the intra-operative findings, radiographic features, and clinical outcomes of a series of patients with chondrolysis following arthroscopic surgery managed with a total shoulder arthroplasty. A retrospective review was performed on 11 patients (average age 39) with shoulder chondrolysis following arthroscopy. Attention was focused on review of the index arthroscopy, radiographs, and functional outcome scores prior to total shoulder arthroplasty, as well as intra-operative cultures, histology, radiographs, and functional outcomes from most recent follow-up. All patients were treated with total shoulder arthroplasty at an average of 26 months after the index arthroscopy. Preoperative and postoperative radiographs were reviewed, and outcomes were compared using validated measurements. Statistically significant improvements in shoulder abduction (89 degrees -123 degrees , P = .027), external rotation (26 degrees -48 degrees , P = .037), total ASES scores (30-77.5, P = .0039), and SST scores (3-8, P = .0078) were noted. Ten patients subjectively rated their outcomes as good or excellent, with 1 as satisfactory. Chondrolysis after shoulder arthroscopy has a rapid clinical progression and is likely multifactorial in etiology. Early results of total shoulder arthroplasty show an opportunity for improvements in pain and function; however, progressive glenoid radiolucencies may develop in these patients.

Evaluation of abduction range of motion and avoidance of inferior scapular impingement in a reverse shoulder model.

The purpose of this study was to determine the effects of prosthetic design and surgical technique of reverse shoulder implants on total abduction range of motion and impingement on the inferior scapular neck. Custom implants in three glenosphere diameters (30, 36, and 42 mm), with 3 different centers of rotation offsets (0, +5, and +10 mm), were placed into a Sawbones scapula (Pacific Research Laboratories, Vashon, WA) in 3 different positions: superior, center, and inferior glenoid. Humeral sockets were manufactured with a 130 degrees , 150 degrees , and 170 degrees neck-shaft angle. Four independent factors (glenosphere diameter, center of rotation offset, glenosphere position on the glenoid, and humeral neck-shaft angle) were compared with the 2 dependent factors of range of motion and inferior scapular impingement. Center of rotation offset had the largest effect on range of motion, followed by glenosphere position. Neck-shaft angle had the largest effect on inferior scapular impingement, followed by glenosphere position. This information may be useful to the surgeon when deciding on the appropriate reverse implant.

Reverse Shoulder Arthroplasty in the Weight-Bearing Versus Non-Weight-Bearing Shoulder: Mid-term Outcomes With Minimum 5-Year Follow-up.

This retrospective review evaluated the mid-term outcomes of cemented reverse shoulder arthroplasty in patients who use the shoulder for weight bearing (WB) vs non-weight-bearing (NWB) patients. Twenty-five shoulders of 21 patients who used their upper extremity for WB (WB group) were treated with cemented reverse shoulder arthroplasty and followed for a minimum of 5 years postoperatively (average, 73 months). Seventy-five consecutive shoulders of 72 patients who were NWB (NWB group) were treated and matched for duration of follow-up (average, 72 months) to serve as a control group. Patients were followed clinically and radiographically. There were no statistically significant differences between the WB group and the NWB group regarding final outcome scores or range of motion. Patient satisfaction was similar between the WB group (92%) and the NWB group (94%). The scapular notching rate was 20% in the WB group compared with 5% in the NWB group (P=.041). Humeral loosening occurred in 12% of the WB group vs 0% of the NWB group (P=.014). The complication rate was higher in the WB group than in the NWB group (12% vs 4%). The WB group and the NWB group had similar outcome scores, range of motion improvements, and patient satisfaction after reverse shoulder arthroplasty. At mid-term follow-up, the WB group had a higher scapular notching rate, humeral loosening rate, and complication rate than the NWB group. [Orthopedics. 2018; 41(3):e328-e333.].

Anatomic Total Shoulder Arthroplasty Versus Reverse Total Shoulder Arthroplasty for Post-Capsulorrhaphy Arthropathy.

Post-capsulorrhaphy arthropathy is a long-term sequela that can develop after open anterior stabilization surgeries, which have historically been performed. The purpose of this study was to compare anatomic total shoulder arthroplasty (ATSA) with reverse total shoulder arthroplasty (RTSA) for the treatment of post-capsulorrhaphy arthropathy. There were 19 patients in the ATSA cohort and 20 in the RTSA cohort. All patients included had a minimum of 2 years of follow-up (ATSA mean, 59.5 months; RTSA mean, 43.8 months). Patients were followed clinically (American Shoulder and Elbow Surgeons score, Simple Shoulder Test score, range of motion analysis, and patient satisfaction) as well as radiographically, allowing a comparison of the 2 cohorts. Mean outcome scores were similar in the ATSA and the RTSA cohorts, with no difference between the 2 groups. The ATSA group had greater postoperative forward elevation (153° vs 139°; P=.01) than the RTSA group, but no other differences were noted in motion. The ATSA group had less satisfied patients (84% vs 95%), a higher complication rate (21% vs 10%), and a higher revision rate (16% vs 0%) compared with the RTSA group. For post-capsulorrhaphy arthropathy, patients treated with ATSA and patients treated with RTSA had comparable improvements in outcome scores and range of motion. However, the complication rate was higher in the ATSA group. All complications in the ATSA cohort were related to subscapularis insufficiency and postoperative anterior instability problems, resulting in a higher revision rate in this cohort (16%) compared with the RTSA cohort (0%). [Orthopedics. 2018; 41(5):275-280.].

Reverse Shoulder Arthroplasty for the Treatment of Rotator Cuff Deficiency: A Concise Follow-up, at a Minimum of 10 Years, of Previous Reports.

We previously evaluated 94 patients (96 shoulders) who underwent reverse shoulder arthroplasty using a central compressive screw with 5.0-mm peripheral locking screws for baseplate fixation and a center of rotation lateral to the glenoid as treatment for end-stage rotator cuff deficiency. The purpose of this study was to report updated results at a minimum follow-up of 10 years. Forty patients (42 shoulders) were available for clinical follow-up. In the patients available for study, implant survivorship, with the end point being revision for any reason, was 90.7%. Since our 5-year report, 2 patients underwent revision surgery; 1 patient sustained a periprosthetic fracture 7 years postoperatively and 1 patient had a dislocation because of chronic shoulder instability at 8 years postoperatively. At a minimum follow-up of 10 years, the patients continued to maintain their improved outcome scores and range of motion, which were comparable with earlier follow-up evaluations. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.