Outcome of Reverse Shoulder Arthroplasty for Patients With Parkinson's Disease: A Matched Cohort Study.

Parkinson's disease (PD) is a progressive neurologic disorder that affects the musculoskeletal system. Currently, the use of reverse shoulder arthroplasty (RSA) for patients with PD has not been adequately studied. The authors sought to determine if RSA provided similar functional outcomes for patients with PD compared with a matched cohort of patients without PD. Between 2004 and 2011, 10 patients with PD (4 men, 6 women) underwent RSA. Patients with PD were matched to patients without PD at a 1:4 ratio based on age (average, 76 years; range, 63-85 years), sex (16 men, 24 women), preoperative diagnosis, and length of follow-up (average, 43 months; range, 24-128 months). Outcome measures included range of motion, visual analog scale (VAS) score, Simple Shoulder Test (SST) score, American Shoulder and Elbow Society (ASES) score, and complication rates. Patients with PD had improvements in SST scores, ASES total scores, and forward flexion; however, they did not show statistically significant improvements in VAS scores, ASES function scores, or other range of motion parameters. There was a significant difference in postoperative functional outcome scores, SST scores, and internal/external rotation between the 2 groups, but no difference in postoperative pain scores, ASES total scores, forward flexion, or abduction. Complications occurred in 4 of 10 patients with PD and 6 of 40 patients without PD. Compared with the matched cohort, patients with PD achieved similar reduction of pain but inferior clinical function following RSA. Improvement in range of motion was less predictable and complication rates were significantly higher in patients with PD. [Orthopedics. 2017; 40(4):e675-e680.].

Reverse shoulder arthroplasty for massive rotator cuff tear: risk factors for poor functional improvement.

BACKGROUND: Some patients unexpectedly have poor functional improvement after reverse shoulder arthroplasty (RSA) for massive rotator cuff tear without glenohumeral arthritis. Our aim was to identify risk factors for this outcome. We also assessed the value of RSA for cases with poor functional improvement vs. METHODS: The study was a retrospective case-control analysis for primary RSA performed for massive rotator cuff tear without glenohumeral arthritis with minimum 2-year follow-up. Cases were defined as Simple Shoulder Test (SST) score improvement of ≤1, whereas controls improved SST score ≥2. Risk factors were chosen on the basis of previous association with poor outcomes after shoulder arthroplasty. Latissimus dorsi tendon transfer results were analyzed as a subgroup. Value was defined as improvement in American Shoulder and Elbow Surgeons (ASES) score per $10,000 hospital cost. RESULTS: In a multivariate binomial logistic regression analysis, neurologic dysfunction (P = .006), age <60 years (P = .02), and high preoperative SST score (P = .03) were independently associated with poor functional improvement. Latissimus dorsi tendon transfer patients significantly improved in active external rotation (-0.3° to 38.7°; P < .01). The value of RSA (ΔASES/$10,000 cost) for cases was 0.8 compared with 17.5 for controls (P < .0001). CONCLUSIONS: Young age, high preoperative function, and neurologic dysfunction were associated with poor functional improvement. Surgeons should consider these associations in counseling and selection of patients. Concurrent latissimus dorsi transfer was successful in restoring active external rotation in a subgroup of patients. The critical economic importance of improved patient selection is emphasized by the very low value of the procedure in the case group.

Complex trauma to the shoulder girdle, including the proximal humerus, the clavicle, and the scapula: current concepts in diagnosis and treatment.

Fractures to the shoulder girdle are common injuries in an aging population. Many techniques and theories lie behind the treatment of such injuries. Knowledge and understanding of current concepts for diagnosing and treating proximal humeral, clavicular, and scapular fractures and the theory behind them will help surgeons make informed decisions with regard to patient care.

Outcome and value of reverse shoulder arthroplasty for treatment of glenohumeral osteoarthritis: a matched cohort.

BACKGROUND: Total shoulder arthroplasty (TSA) is commonly used to treat glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Recently, reverse shoulder arthroplasty (RSA) has been used for GHOA patients who are elderly or have eccentric glenoid wear. We evaluated patients with GHOA scheduled to have TSA but who were changed to RSA because of intraoperative difficulties with the glenoid component or instability and compared them with a cohort that underwent TSA to determine if the groups had similar outcomes. METHODS: We identified 24 consecutive GHOA patients who underwent RSA and matched them to 96 patients who underwent TSA. Glenoid wear and rotator cuff musculature were assessed with preoperative computed tomography scans. Direct hospital costs of the procedure were collected. RESULTS: Postoperative American Shoulder and Elbow Surgeons score, Simple Shoulder Test score, and range of motion were similar between the 2 groups. Five TSA patients had radiographic glenoid loosening, whereas no RSA patients did. Neither group required a revision. One RSA patient required surgery for treatment of a periprosthetic fracture. RSA was $7274 more costly than TSA, related mainly to implant cost. CONCLUSIONS: Patients with GHOA who were converted intraoperatively to RSA because of improper seating of the glenoid trial or persistent posterior subluxation had outcomes comparable to those of a similar group of patients in whom TSA was performed. At midterm follow-up, TSA is associated with lower cost than RSA. The higher rate of radiographic loosening in the TSA group warrants longer follow-up to assess revision costs. In cases in which a TSA cannot be performed with confidence, RSA is a reasonable alternative.

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.

The effects of glenoid wear patterns on patients with osteoarthritis in total shoulder arthroplasty: an assessment of outcomes and value.

BACKGROUND: Despite the success of total shoulder arthroplasty (TSA), concerns remain about the longevity of the implant, in particular, glenoid component survivorship. The purpose of this study was to determine whether preoperative glenoid wear patterns affect clinical outcomes and value in patients undergoing TSA. METHODS: A comparative cohort study was conducted of 309 patients with a total of 344 TSA procedures, performed for primary glenohumeral osteoarthritis. Computed tomography scans were obtained in all patients, with preoperative glenoid wear pattern characterized as either concentric (n = 196; follow-up time, 49.2 months) or eccentric (n = 148; follow-up time, 52.3 months) according to a modified Levine classification. A clinical, radiographic, and economic assessment was performed between the 2 wear patterns. RESULTS: There was no significant difference in American Shoulder and Elbow Surgeons (ASES) score in the concentric group (80.8 ± 20.8) compared with the eccentric group (77.6 ± 21.2) at final follow-up (P = .159). Range of motion and final visual analog scale for pain score were similar between the 2 groups. Radiographic evidence of gross glenoid loosening was significantly lower in the concentric group [11 of 195 (5.6%)] compared with the eccentric group [18 of 147 (12.2%)] (P = .030). Revision rates were similar between the concentric group [4 of 195 (2.0%)] and the eccentric group [3 of 147 (2.0%)]. A value assessment also showed no significant difference between the concentric and eccentric groups [concentric 26.1 vs. eccentric 25.5 (ΔASES score/$10,000 hospital cost) (P = .479)]. CONCLUSIONS: Similar clinical results and value can be expected with both concentric and eccentric glenoid wear patterns in TSA. Concerns arise, however, as the eccentric group demonstrated a more than 2-fold increased rate of glenoid component loosening compared with the concentric group.

Low incidence of tendon rerupture after distal biceps repair by cortical button and interference screw.

BACKGROUND: The use of cortical suspensory fixation in conjunction with an interference screw to treat distal biceps ruptures has yielded favorable results. However, literature examining the incidence of fixation failure in a large consecutive series of patients treated with this technique is lacking. METHODS: A retrospective review of electronic medical records identified 170 distal biceps ruptures in 168 consecutive patients (164 men and 4 women) treated using a cortical button in conjunction with an interference screw. The study group was an average age of 48 years (range, 20-71 years). Records were reviewed from the time of the initial clinic visit to the most recent follow-up. Early failures were defined as those that occurred within 12 weeks of the index procedure. Failed repair was defined as tendon defect, deformity, or significant weakness in supination. RESULTS: The early incidence of failure was 1.2%, with 2 of the fixations meeting the criteria for failure. One patient had significant brachial artery thrombosis. Other complications included posterior interosseous nerve palsy, lateral antebrachial cutaneous nerve-related complication, and numbness about the radial nerve. CONCLUSION: The use of a cortical suspensory fixation device in conjunction with an interference screw is an effective method of repairing a distal biceps rupture, with a low early rate of failure.

Accuracy and reliability of the Mayo Elbow Performance Score.

PURPOSE: To test the reliability of the Mayo Elbow Performance Score (MEPS) and compare it with a validated outcomes instrument, the American Shoulder and Elbow Surgeons (ASES) score. METHODS: A total of 42 patients with the chief problem of elbow dysfunction formed the study cohort. Patients with an immediate surgical indication or treatment at the index visit were excluded. The others completed an MEPS questionnaire; at a second visit 2 to 3 weeks later, they completed another MEPS questionnaire and were evaluated with the ASES elbow assessment. Reliability and accuracy were calculated using 2-tailed Pearson correlation coefficients with 95% confidence intervals. Pearson coefficients greater than 0.8 indicated strong agreement. RESULTS: The average MEPS score at the initial visit was 58. At the second visit, the average MEPS score was 69 and the average ASES score was 78. The Pearson coefficient for MEPS scores at the 2 time points averaged 0.82, and between the MEPS and ASES scores averaged 0.83. Both coefficients indicated strong agreement. CONCLUSIONS: The MEPS has strong reliability when assessed at different times and when compared with a validated elbow outcomes instrument. Differences in compared scores of approximately 10 points indicate some patient improvement between time points; however, 95% confidence intervals, standard deviations, and ranges were essentially equivalent between and among tests, indicating similar accuracy. CLINICAL RELEVANCE: The MEPS is a reliable outcomes instrument for clinical studies of elbow function that is used to assess nonsurgical treatment.

Effects of altered amygdalar neuropeptide Y expression on anxiety-related behaviors.

Neuropeptide Y (NPY) decreases anxiety-related behaviors in various animal models of anxiety. The purpose of the present study was to examine the role of the amygdalar NPY system in anxiety-related responses in the elevated plus maze. The first experiment determined if herpes virus-mediated alterations in amygdalar NPY levels would alter anxiety-related behaviors in the elevated plus maze. Viral vectors encoding NPY, NPY antisense, or LacZ (control virus) were bilaterally injected into the amygdala, and 4 days postinjection, rats were tested in the elevated plus maze test. NPY-like immunoreactivity (NPY-ir) was measured in the amygdala of these rats. In rats injected with the viral vector encoding NPY, reduced anxiety-related behaviors in the elevated plus maze accompanied by moderate increases in NPY-ir were detected compared to NPY-antisense viral vector-treated subjects. Elevated plus maze behavior did not differ compared to LacZ-treated controls. NPY overexpression at this time point was also suggested by enhanced NPY mRNA expression seen in the amygdala 4 days postinjection using real-time polymerase chain reaction analysis. Experiment 2 was conducted to provide further evidence for a role of amygdalar NPY in regulating anxiety-related behaviors in the elevated plus maze test. The nonpeptide NPY Y1 receptor antagonist, BIBP 3226 (1.5 microg/microl), was bilaterally injected into the amygdala and rats were tested in the elevated plus maze test. Rats receiving BIBP 3226 exhibited increased anxiety-related behaviors in this test. The results of these experiments provide further support for the role of amygdalar NPY in anxiety-related behaviors.