Mitzi S. Laughlin

Characteristics of Clinical Shoulder Research Over the Last Decade: A Review of Shoulder Articles in The Journal of Bone & Joint Surgery from 2004 to 2014

BACKGROUND The purpose of this study was to determine characteristics and trends in published shoulder research over the last decade in a leading orthopaedic journal. METHODS We examined all clinical shoulder articles published in The Journal of Bone & Joint Surgery from 2004 to 2014. The number of citations, authorship, academic degrees of the authors, country and institution of origin, topic, level of evidence, positive or nonpositive outcome, and inclusion of validated patient-reported outcome measures were assessed for each article. RESULTS Shoulder articles that included an author with an advanced research degree (MD [Doctor of Medicine] with a PhD [Doctor of Philosophy] or other advanced degree) increased during the study period (p = 0.047). Level-I, II, and III studies were more likely to have an author with an advanced research degree, and Level-IV studies were more likely to have MDs only (p = 0.03). Overall, there was great variability of outcome measures, with at least thirty-nine different validated or nonvalidated outcome measures reported. CONCLUSIONS Over the last decade, there was an improvement in the level of evidence of shoulder articles published in The Journal of Bone & Joint Surgery that corresponds with recent emphasis on evidence-based medicine. A consensus is needed in shoulder research for more consistent application of validated patient-reported outcome measurement tools.

The Bland-Altman Method Should Not Be Used in Regression Cross-Validation Studies.

The purpose of this study was to demonstrate the bias in the Bland-Altman (BA) limits of agreement method when it is used to validate regression models. Data from 1,158 men were used to develop three regression equations to estimate maximum oxygen uptake (R2 = .40, .61, and .82, respectively). The equations were evaluated in a cross-validation sample of 581 men. The BA means and differences were correlated (p < .001) in the cross-validation sample for each model (r = .55, .39, and .26, respectively), thus demonstrating bias. The BA method is inappropriate for validation of regression models. Validation of regression equations is properly conducted by plotting the residuals against the estimated values and examining the magnitude of the estimation error.

Clinical and radiographic outcomes after total shoulder arthroplasty with an anatomic press-fit short stem

BACKGROUND There is limited information assessing outcomes after total shoulder arthroplasty (TSA) with a press-fit short stem. The purpose of this study was to evaluate early clinical and radiographic outcomes and complications after TSA with an anatomic press-fit short stem. METHODS We identified 118 TSAs completed with press-fit short stem and minimum 2-year follow-up; 85 of these patients had a grit-blasted (GB) short stem placed, whereas 33 patients had short stems with proximal porous coating (PPC). Shoulder function scores, active mobility measurements, and radiographs were assessed. RESULTS The average age at surgery was 66.7 years, with average follow-up of 3 years. Significant improvements were noted for all shoulder function scores and active mobility measurements from the preoperative state to final follow-up (P < .001). There was no stem loosening in any patients with minimum 2-year follow-up; however, 3 female patients with GB stems had gross loosening of their humeral components before 1 year, 2 requiring revision. Radiolucent lines around the humeral component were found in 5.9% without evidence of loosening. Osseous resorption at the medial cortex was noted in 9.3%. Of patients with PPC stems, no patients were observed to have radiolucent lines compared with 8.2% in the GB group (P = .09). CONCLUSION TSAs with anatomic press-fit short stem showed significant clinical improvements from the preoperative state to final short-term follow-up, with few complications and minimal radiographic changes. Lack of PPC may contribute to early loosening in patients with poor bone quality. The authors now use a short stem with PPC.

Vigorous exercise mobilizes CD34+ hematopoietic stem cells to peripheral blood via the β2-adrenergic receptor

Acute dynamic exercise mobilizes CD34+ hematopoietic stem cells (HSCs) to the bloodstream, potentially serving as an economical adjuvant to boost the collection of HSCs from stem cell transplant donors. The mechanisms responsible for HSC mobilization with exercise are unknown but are likely due to hemodynamic perturbations, endogenous granulocyte-colony stimulating factor (G-CSF), and/or β2-adrenergic receptor (β2-AR) signaling. We characterized the temporal response of HSC mobilization and plasma G-CSF following exercise, and determined the impact of in vivo β-AR blockade on the exercise-induced mobilization of HSCs. Healthy runners (n = 15) completed, in balanced order, two single bouts of steady state treadmill running exercise at moderate (lasting 90-min) or vigorous (lasting 30-min) intensity. A separate cohort of healthy cyclists (n = 12) completed three 30-min cycling ergometer trials at vigorous intensity after ingesting: (i) 10 mg bisoprolol (β1-AR antagonist); (ii) 80 mg nadolol (β1 + β2-AR antagonist); or (iii) placebo, in balanced order with a double-blind design. Blood samples collected before, during (runners only), immediately after, and at several points during exercise recovery were used to determine circulating G-CSF levels (runners only) and enumerate CD34+ HSCs by flow cytometry (runners and cyclists). Steady state vigorous but not moderate intensity exercise mobilized HSCs, increasing the total blood CD34+ count by ∼4.15 ± 1.62 Δcells/µl (+202 ± 92%) compared to resting conditions. Plasma G-CSF increased in response to moderate but not vigorous exercise. Relative to placebo, nadolol and bisoprolol lowered exercising heart rate and blood pressure to comparable levels. The number of CD34+ HSCs increased with exercise after the placebo and bisoprolol trials, but not the nadolol trial, suggesting β2-AR signaling mediated the mobilization of CD34+ cells [Placebo: 2.10 ± 1.16 (207 ± 69.2%), Bisoprolol 1.66 ± 0.79 (+163 ± 29%), Nadolol: 0.68 ± 0.54 (+143 ± 36%) Δcells/µL]. We conclude that the mobilization of CD34+ HSCs with exercise is not dependent on circulating G-CSF and is likely due to the combined actions of β2-AR signaling and hemodynamic shear stress.

Reverse Shoulder Arthroplasty for Management of Postinfectious Arthropathy With Rotator Cuff Deficiency

Treatment of patients with rotator cuff deficiency and arthritis in the setting of a prior glenohumeral infection (postinfectious arthropathy) is complex, with little evidence to guide treatment. The current authors present their approach to management of these patients and clinical outcomes after reverse shoulder arthroplasty (RSA). All primary RSAs performed for postinfectious arthropathy and rotator cuff deficiency with native glenohumeral joints were identified in a prospective shoulder arthroplasty registry. Eight patients with a minimum of 2-year follow-up were included in the analysis. Clinical outcomes, including the Constant score, the American Shoulder and Elbow Surgeons (ASES) score, the Western Ontario Osteoarthritis Shoulder (WOOS) index, the Single Assessment Numeric Evaluation (SANE) score, and range of motion measurements, were assessed preoperatively and at final follow-up. At an average follow-up of 4.4 years, no patient had a clinically detectable recurrence of infection. Significant improvements were noted in all outcome scores from preoperative evaluation to final follow-up after RSA, including Constant score (P=.003), ASES score (P<.001), WOOS index (P=.002), SANE score (P=.025), forward flexion (P<.001), abduction (P<.001), and external rotation (P=.020). Seven of 8 patients reported they were satisfied or very satisfied at final follow-up. Reverse shoulder arthroplasty can be performed in patients without significant medical comorbidities in the setting of postinfectious arthropathy and rotator cuff deficiency with a low risk of recurrence of infection. Significant clinical improvements were noted at short-term follow-up.

Financial Impact of Third-Party Reimbursement Due to Changes in the Definition of ICD-9 Arthroscopy Codes 29880, 29881, and 29877

BACKGROUND The relative value units (RVUs) of the International Classification of Diseases, Ninth Revision (ICD-9) codes 29880 (partial medial and lateral meniscectomy) and 29881 (partial medial or lateral meniscectomy) were decreased from 2011 to 2012, and codes 29877 (debridement or shaving articular cartilage) and G0289 (debridement of articular cartilage or removal of foreign/loose body in a separate compartment) were bundled with codes 29880 and 29881. Our goal was to quantify the decrease in physician reimbursement in 2012 and to determine if there was an increase in the use of codes 29875 (limited synovectomy), 29876 (major synovectomy), and 29879 (abrasion arthroplasty or microfracture). METHODS We analyzed a structured query language database for ICD-9 coding and third-party reimbursement of a large group practice. All knee arthroscopy cases were identified, and codes 29880, 29881, and 29877 were specifically assessed and compared between the years 2011 and 2012. The data were analyzed for number of cases, changes in code utilization, reimbursement per individual code and combinations of codes, and change in Medicare reimbursement between years. Statistical analyses were performed with chi-square tests to determine the difference in cases per year, and independent t tests were used to evaluate differences in reimbursement rates by insurance provider per year. RESULTS Mean surgeon third-party reimbursement for code 29880 decreased from

External loading is dependent upon game state and varies by position in professional women’s soccer

734.33 in 2011 to

Lymphocytes and monocytes egress peripheral blood within minutes after cessation of steady state exercise: A detailed temporal analysis of leukocyte extravasation

630.40 in 2012 and from

Increased scapular spine fractures after reverse shoulder arthroplasty with a humeral onlay short stem: an analysis of 485 consecutive cases

709.17 to

Autologous serum collected 1 h post-exercise enhances natural killer cell cytotoxicity

639.18 for code 29881. Comparing the combination of codes 29880/29877 in 2011 to 29880 in 2012, mean reimbursement decreased from