Editorial Commentary: Social Determinants of Health Influence the Success of Shoulder Rotator Cuff Repair Outcomes: When You Do Everything Right, Yet Things Still Go Wrong.

Our ability to perform a technically sound surgery is not sufficient to ensure patients have an excellent clinical outcome. Social determinants of health disparities (SDHDs) profoundly impact health equality. Health disparities that exist in the United States are risk factors for inferior patient-reported outcomes and result in greater complication rates following rotator cuff repair surgery. The presence of SDHDs was associated with an increased risk of revision, stiffness, emergency department visits, medical complications, and costs. Economic and educational SDHDs were associated with the greatest risk of 1-year revision surgery. Improved understanding of these social variables can help with risk identification preoperatively. Surgeons may employ additional, holistic, bio-psycho-social, perioperative resources to provide high-quality, value-based care to at-risk patients who might be marginalized by our health care system.

Clinically Depressed Patients Having Anterior Cruciate Ligament Reconstruction Show Improved but Inferior Rate of Achieving Minimum Clinically Important Difference for Patient-Reported Outcomes Measurement Information System Compared With Situationally Depressed or Nondepressed Patients.

PURPOSE: To determine whether the preoperative diagnosis of depression predicted worse postoperative outcomes, including physical therapy (PT) compliance, return-to-sport, and patient-reported outcomes using the Patient-Reported Outcomes Measurement Information System (PROMIS) after anterior cruciate ligament (ACL) reconstruction. METHODS: A multisurgeon series of consecutive patients who had undergone ACL reconstruction with minimum 2-year follow-up were included. Chart review was conducted to determine depression diagnosis status, demographic data, rehabilitation PT compliance, return to sports, and patient-reported outcome data using PROMIS. Patients who met the PROMIS threshold for mild depression but did not carry a clinical diagnosis of depression were classified as "situationally depressed." RESULTS: Ninety-five of 115 consecutive patients (81%) met inclusion criteria with an average follow-up of 34 ± 1.9 months. Fourteen patients (15%) had a preoperative diagnosis of depression, whereas 21 (22%) were considered situationally depressed. Clinically depressed patients had a greater rate of PT noncompliance (33.2% ± 17.6% vs 21.9% ± 12.6%; P = .02) and a lower postoperative PROMIS Physical Function (50.8 ± 7.7 vs 57.8 ± 11.0; P = .03 compared with patients without depression. Situationally depressed patients had lower preoperative physical function (35.4 vs 42.5; P = .04) with no differences in postoperative outcomes scores compared to the non-depressed cohort.19/21 (90.5%) of situationally depressed patients had postoperative resolution of their depressive symptoms. CONCLUSIONS: Situationally depressed patients without a clinical diagnosis of depression can expect significant improvements in both pain and function, as well as a resolution of their depressed mood based on PROMIS scores as they progress through recovery after ACL reconstruction. Clinically depressed patients also experience significant improvements; however, their rate of achieving the minimum clinically important difference for PROMIS outcomes may be less than their nondepressed or situationally depressed counterparts. LEVEL OF EVIDENCE: III, prognostic comparative trial.

An Innovative Seven-year Physician Scientist Residency Training Program That Addresses the Shortage of Academic Surgeons.

Due to the declining number of scientifically trained physicians and increasing demand for high-quality literature, our institution pioneered a seven-year Physician Scientist Training Program (PSTP) to provide research-oriented residents the knowledge and skills for a successful academic career. The present study sought to identify orthopaedic surgeons with MD/PhD degrees, residency programs with dedicated research tracks, and to assess the effectiveness of the novel seven-year program in training prospective academic orthopaedic surgeons. Surgeons with MD/PhD degrees account for 2.3% of all 3,408 orthopaedic faculty positions in U.S. residency programs. During the last 23 years, our PSTP residents produced 752 peer-reviewed publications and received $349,354 from 23 resident-authored extramural grants. Eleven of our seven-year alumni practice orthopaedic surgery in an academic setting. The seven-year PSTP successfully develops clinically trained surgeon scientists with refined skills in basic science and clinical experimental design, grant proposals, scientific presentations, and manuscript preparation. (Journal of Surgical Orthopaedic Advances 31(3):144-149, 2022).

Cemented versus uncemented fixation of second-generation Trabecular Metal glenoid components: minimum 5-year outcomes.

BACKGROUND: Total shoulder arthroplasty (TSA) with second-generation Trabecular Metal™ implants (Zimmer, Warsaw, IN, USA) has shown good short-term outcomes. Differences in outcomes between cemented and uncemented fixation are unknown. This study compared the clinical, radiographic, and patient-rated outcomes of TSA with cemented vs. uncemented TM glenoids at minimum 5-year follow-up. METHODS: Patients who underwent anatomic TSA with second-generation TM glenoid components for primary osteoarthritis were identified for minimum 5-year follow-up. The patients were divided into 2 groups: cemented and uncemented glenoid fixation. Outcome measures included implant survival, patient-rated outcome scores (Patient-Reported Outcomes Measurement Information System [PROMIS] and American Shoulder and Elbow Surgeons scores), shoulder range of motion, and radiographic analysis. Findings were compared between groups. RESULTS: The study included 55 shoulders: 27 in the cemented group (21 with full radiographic follow-up) and 28 in the uncemented group (22 with full radiographic follow-up). Both groups had similar follow-up times (6.6 years in cemented group vs. 6.7 years in uncemented group, P = .60). Moreover, the groups did not differ significantly in sex composition, age at the time of surgery, or preoperative Walch glenoid grade distribution. No patients required revision surgery. The 2 groups had similar preoperative range of motion, but patients in the uncemented group had greater follow-up forward flexion (P = .03), external rotation (P < .01), and lateral elevation (P = .03) than did patients in the cemented group. PROMIS scores were not significantly different between groups. American Shoulder and Elbow Surgeons scores were similar (89.8 in cemented group vs. 94.1 in uncemented group, P = .21). Mid-term radiographs showed a metal debris rate of 24% in the cemented group and 27% in the uncemented group. Although these values were not significantly different (P = .90), the frequency of mild metal debris (grade 1-2), when present, was greater in the uncemented group (grade 2 in 6 shoulders) than in the cemented group (grade 1 in 4 and grade 2 in 1, P = .02). There was a greater presence of mild (grade 1) radiolucent lines in the uncemented group (64%) than in the cemented group (29%, P < .01). No glenoid had evidence of loosening (defined by a change in position or radiolucent lines > 2 mm). The presence of metal debris and radiolucent lines did not have a significant effect on clinical outcomes. CONCLUSION: At minimum 5-year follow-up, TSA patients with TM glenoids demonstrated excellent clinical and patient-reported outcomes with a 100% implant survival rate, regardless of cemented vs. uncemented fixation. However, the uncemented group showed a significantly higher rate of radiolucent lines and a higher frequency of mild metal debris. These radiographic findings did not affect the clinical outcomes, and their implications for long-term outcomes and prosthesis survival is unknown.

Diversity among academic orthopedic shoulder and elbow surgery faculty in the United States.

BACKGROUND: The purpose of this study was to perform a cross-sectional analysis of diversity among academic shoulder and elbow surgeons in the United States. METHODS: US shoulder and elbow surgeons who participated in shoulder and elbow fellowship and/or orthopedic surgery resident education as of November 2018 were included. Demographic data (age, gender, race), practice setting, years in practice, academic rank, and leadership roles were collected through publicly available databases and professional profiles. Descriptive statistics were performed and findings were compared between different racial and gender groups. Statistical significance was set at P <.05. RESULTS: A total of 186 orthopedic shoulder and elbow surgeons were identified as participating in shoulder and elbow fellowship and/or orthopedic surgery residency education. Overall, 83.9% were white, 14.5% were Asian, 1.1% were Hispanic, 0.5% were an other race, and 0% were African American. In addition, 94.6% of surgeons were male, whereas 5.4% were female. Further, 64.5% of all surgeons had been in practice for >10 years, and 39.2% worked in an urban setting. Less than half (40.3%) of the surgeons practicing primarily at academic institutions held a professor rank. White surgeons had a significantly greater time in practice vs. nonwhite surgeons (mean 18.8 vs. 12.6 years, P < .01) and were more likely to hold a professor rank (44.0% vs. 21.7%, P = .04). CONCLUSION: Racial and gender diversity among US shoulder and elbow surgeons who participate in fellowship and residency education is lacking. Hispanic, African American, and female surgeons are underrepresented. Efforts should be made to identify the reasons for these deficiencies and address them to further advance the field of orthopedic shoulder and elbow surgery.

The Influence of Naproxen on Biological Factors in Leukocyte-Rich Platelet-Rich Plasma: A Prospective Comparative Study.

PURPOSE: To quantify and compare normative catabolic and anabolic factor concentrations in leukocyte-rich platelet-rich plasma (LR-PRP) at various time points, including baseline, 1 week after initiating naproxen use, and after a 1-week washout period. METHODS: Asymptomatic healthy donors aged between 18 and 70 years were recruited (average age, 36.6 years; range, 25-64 years). Subjects were excluded from the study if they were actively taking any prescribed medications or nonsteroidal anti-inflammatory drugs (NSAIDs) or if they had any of the following at present or previously: blood or immunosuppression disorders, cancer, osteonecrosis, rheumatoid arthritis, avascular necrosis, NSAID intolerance, gastrointestinal or peptic ulcer disease, or kidney dysfunction. The anabolic factors vascular endothelial growth factor, fibroblast growth factor 2, platelet-derived growth factor AB (PDGF-AB), and platelet-derived growth factor AA (PDGF-AA) and the catabolic factors interleukin (IL) 1ß, IL-6, IL-8, and tumor necrosis factor α in LR-PRP were measured. Peripheral blood was drawn at 3 time points: baseline, after 1 week of naproxen use, and after a 1-week washout period. RESULTS: The angiogenic factors PDGF-AA (44% decrease in median) and PDGF-AB (47% decrease) significantly declined from baseline (P < .05) after 1 week of naproxen use. There was a significant recovery (P < .05) of PDGF-AA (94% increase) and PDGF-AB (153% increase) levels after the 1-week washout period, with a return to baseline levels. The catabolic factor IL-6 also had a significant decline from baseline (77% decrease in median, P < .05) after 1 week of naproxen use. After a 1-week washout period, the IL-6 level was similar to the baseline level (130% increase, P < .05). CONCLUSIONS: Naproxen use diminished several biological factors in LR-PRP; however, a 1-week washout period was sufficient for the recovery of PDGF-AA, PDGF-AB, and IL-6 to return to baseline levels. Tumor necrosis factor α, IL-1ß, IL-8, vascular endothelial growth factor, and fibroblast growth factor 2 did not show differences between the 3 time points of data collection. Discontinuing NSAIDs for a minimum of 1 week before LR-PRP treatment may improve certain biological factor levels. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Five-Year Outcomes After Arthroscopic Repair of Partial-Thickness Supraspinatus Tears.

PURPOSE: To investigate clinical outcomes in patients who underwent arthroscopic repair of isolated partial-thickness rotator cuff tears (PTRCTs) of the supraspinatus tendon with a minimum follow-up period of 5 years. METHODS: All patients who had undergone arthroscopic repair of isolated PTRCTs at least 5 years earlier were included. Preoperatively and postoperatively, the American Shoulder and Elbow Surgeons, QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire), and Short Form 12 Physical Component Summary scores were collected, along with postoperative satisfaction (10-point scale) and return to activity. The associations between (1) patient age and outcome scores and (2) location of partial-thickness tear (articular vs bursal sided) and outcome scores were evaluated. Failure was defined as revision surgery of the rotator cuff repair. RESULTS: The study included 24 shoulders (24 patients comprising 9 women and 15 men). Follow-up data were available on 20 shoulders (7 women and 13 men, 83% follow-up) at a mean of 6 ± 1 years postoperatively. The mean age at index surgery was 55 ± 11 years; 6 bursal- and 14 articular-sided tears were repaired. No patient required revision surgery. All scores significantly improved from preoperatively to postoperatively (P < .05); the median satisfaction rating (1, not satisfied; 10, completely satisfied) was 10 (range, 1-10). Neither patient age nor tear location correlated with outcome scores (P > .05). Seventeen patients indicated that they participated in previous recreational activity. Of these patients, 13 (76%) returned to the original level or a similar level of activity, 3 (18%) returned to activity at a lower level, and only 1 (6%) indicated an inability to return to activity. CONCLUSIONS: Patients undergoing arthroscopic repair of PTRCTs can expect excellent clinical outcomes with low failure rates at midterm follow-up given that no patient progressed to revision rotator cuff repair during follow-up. The return-to-activity rate was very high after repair of isolated PTRCTs. Neither patient age nor tear location was associated with outcome scores. LEVEL OF EVIDENCE: Level IV, retrospective case series.

The Development of a Xenograft-Derived Scaffold for Tendon and Ligament Reconstruction Using a Decellularization and Oxidation Protocol.

PURPOSE: To evaluate the biological, immunological, and biomechanical properties of a scaffold derived by architectural modification of a fresh-frozen porcine patella tendon using a decellularization protocol that combines physical, chemical, and enzymatic modalities. METHODS: Porcine patellar tendons were processed using a decellularization and oxidation protocol that combines physical, chemical, and enzymatic modalities. Scaffolds (n = 88) were compared with native tendons (n = 70) using histologic, structural (scanning electron microscopy, porosimetry, and tensile testing), biochemical (mass spectrometry, peracetic acid reduction, DNA quantification, alpha-galactosidase [α-gal] content), as well as in vitro immunologic (cytocompatibility, cytokine induction) and in vivo immunologic nonhuman primate analyses. RESULTS: A decrease in cellularity based on histology and a significant decrease in DNA content were observed in the scaffolds compared with the native tendon (P < .001). Porosity and pore size were increased significantly (P < .001). Scaffolds were cytocompatible in vitro. There was no difference between native tendons and scaffolds when comparing ultimate tensile load, stiffness, and elastic modulus. The α-gal xenoantigen level was significantly lower in the decellularized scaffold group compared with fresh-frozen, nondecellularized tissue (P < .001). The in vivo immunological response to implanted scaffolds measured by tumor necrosis factor-α and interleukin-6 levels was significantly (P < .001) reduced compared with untreated controls in vitro. These results were confirmed by an attenuated response to scaffolds in vivo after implantation in a nonhuman primate model. CONCLUSIONS: Porcine tendon was processed via a method of decellularization and oxidation to produce a scaffold that possessed significantly less inflammatory potential than a native tendon, was biocompatible in vitro, of increased porosity, and with significantly reduced amounts of α-gal epitope while retaining tensile properties. CLINICAL RELEVANCE: Porcine-derived scaffolds may provide a readily available source of material for musculoskeletal reconstruction and repair while eliminating concerns regarding disease transmission and the morbidity of autologous harvest.

Cyclists Have Greater Chondromalacia Index Than Age-Matched Controls at the Time of Hip Arthroscopy.

PURPOSE: To evaluate the clinical symptoms and intraoperative pathology associated with hip pain in the cyclist compared with a matched hip arthroscopy surgical group. METHODS: In an institutional review board-approved study, we retrospectively reviewed a prospective database of 1,200 consecutive hip arthroscopy patients from 2008 to 2015. Adult patients were identified who reported cycling as a major component of their activity. Patients were age, gender, and body mass index matched to a control, noncycling group. Pain symptoms, preoperative examinations, radiographic and operative findings were compared. Primary outcome variables included the femoral and acetabular Outerbridge chondromalacia grade. Additional outcome measurements included the involved area and the chondromalacia index (CMI; the product of the Outerbridge chondromalacia grade and surface area [mm2 × severity]). RESULTS: A total of 167 noncyclists were matched to the cycling group (n = 16). Cyclists had significantly greater femoral head chondromalacia grade (2.0 [95% confidence interval (CI), 1.5-2.5] v 1.4 [95% CI, 1.3-1.6], P = .043), femoral head chondromalacia area (242 mm2 [95% CI, 191-293 mm2] v 128 mm2 [95% CI, 113-141 mm2], P < .001), and femoral head CMI (486 [95% CI, 358-615] v 247 [95% CI, 208-286], P = .001) assessed intraoperatively. Hip pain in cyclists positively correlated with an increased acetabular center-edge angle (R = 0.261, P < .001) and an increased Tonnis grade (R = 0.305, P < .001). Cyclists were also more likely to have a coxalgic gait on physical examination (R = 0.250, P = .006). CONCLUSIONS: Cyclists had a greater degree of femoral chondromalacia than a matched group of noncyclists. Cycling activity positively correlated with the presence of femoral chondromalacia with clinically significant gait alterations. These data support the hypothesis that cyclists with hip pain have more chondral pathology than a similar group of other patients with hip pain. Ultimately, cyclists with hip pain should be identified as higher risk for more advanced chondral damage. LEVEL OF EVIDENCE: Level III, case-control study, therapeutic.

Arthroscopic Management of Hip Chondral Defects: A Systematic Review of the Literature.

PURPOSE: To critically evaluate the evidence for arthroscopic management of chondral defects in the hip through a systematic literature review. METHODS: A systematic literature review was performed to identify all articles addressing the arthroscopic management of chondral defects about the hip. Case reports, open techniques, and those associated with osteonecrosis were excluded. Articles were assessed for sample size, location, severity, and size of chondral defects, and the surgical technique. Associated injuries, follow-up duration (months), and functional outcomes were recorded. Study cohorts were defined by a surgical technique (debridement v microfracture v autologous chondrocyte transplantation [ACT]). Statistical analysis was performed with a χ(2) test and analysis of variance with post hoc pairwise analysis for categorical and continuous data, respectively, with significance defined as P < .05. RESULTS: The literature search identified 269 articles, of which 12 clinical studies met inclusion criteria for this analysis. After pooling the data, there were 579 (64.7%) debridements, 279 (31.2%) microfracture, and 37 (4.1%) ACT performed. Patients were followed for an average of 27.1 months (range: 5 to 72 months). All lesions treated with either a microfracture or ACT were high grade (Outerbridge 3 to 4). However, lesion size was significantly larger in ACT-treated patients compared with those who underwent microfracture (357.3 ± 96.0 mm(2)v 149.5 ± 20.7 mm(2); P = .020). All cohorts showed significant improvement in functional outcomes after hip arthroscopy (P < .001). CONCLUSIONS: This systematic review showed that arthroscopic debridement, microfracture, and ACT are associated with equivalent improvement in clinical outcomes in patients with high-grade chondral defects in the hip in the short- and midterm follow-up. In addition, although there were no differences in patient characteristics and demographics based on the surgical technique, we confirmed the hypothesis that lesion size varied significantly between arthroscopic techniques, and that the decision to use one technique over another may be determined by the size of the defect. Therefore, lesion size is likely to influence the development of hip- and technique-specific indications, and may also represent a useful metric for success of surgical intervention. LEVEL OF EVIDENCE: Level IV, systematic review of Level III and IV studies.

Multiple Small Diameter Drillings Increase Femoral Neck Stability Compared with Single Large Diameter Femoral Head Core Decompression Technique for Avascular Necrosis of the Femoral Head.

Femoral head core decompression is an efficacious joint-preserving procedure for treatment of early stage avascular necrosis. However, postoperative fractures have been described which may be related to the decompression technique used. Femoral head decompressions were performed on 12 matched human cadaveric femora comparing large 8mm single bore versus multiple 3mm small drilling techniques. Ultimate failure strength of the femora was tested using a servo-hydraulic material testing system. Ultimate load to failure was compared between the different decompression techniques using two paired ANCOVA linear regression models. Prior to biomechanical testing and after the intervention, volumetric bone mineral density was determined using quantitative computed tomography to account for variation between cadaveric samples and to assess the amount of bone disruption by the core decompression. Core decompression, using the small diameter bore and multiple drilling technique, withstood significantly greater load prior to failure compared with the single large bore technique after adjustment for bone mineral density (p< 0.05). The 8mm single bore technique removed a significantly larger volume of bone compared to the 3mm multiple drilling technique (p< 0.001). However, total fracture energy was similar between the two core decompression techniques. When considering core decompression for the treatment of early stage avascular necrosis, the multiple small bore technique removed less bone volume, thereby potentially leading to higher load to failure.

Superficial acral fibromyxoma and other slow-growing tumors in acral areas.

Superficial acral fibromyxoma (SAFM) is a rare fibromyxoid mesenchymal tumor with a predilection for the distal extremities and frequent nail bed involvement. Superficial acral fibromyxoma typically arises as a solitary, slow-growing nodule on a toe or finger, with the great toe being the most commonly affected site. Histopathologically, SAFM characteristically presents as a well-circumscribed but unencapsulated dermal tumor composed of spindle and stellate cells in a loose storiform or fascicular arrangement embedded in a myxoid, myxocollagenous, or collagenous stroma. The tumor often occupies the entire dermis and may extend into the subcutis and occasionally the underlying fascia and bone. The characteristic immunohistochemical profile of SAFM includes expression of CD34, epithelial membrane antigen (EMA), and CD99; it is notably negative for S-100 protein. We report 3 cases of SAFM and also provide a review of the literature on the clinical and histopathologic presentations of this unique entity as well as the differential diagnosis.

Randomized comparison of volar locking plates and intramedullary nails for unstable distal radius fractures.

PURPOSE: To compare minimally invasive intramedullary nails (IMN) and volar locking plates (VLP) for the treatment of unstable distal radius fractures by evaluating postoperative subjective, radiographic, and functional outcomes. The hypothesis was that IMN patients would have less pain and required less pain medication in the early postoperative period and returned to work earlier than VLP patients. METHODS: Sixty patients with closed, displaced, unstable, extra-articular, metaphyseal fractures of the distal radius were randomized to receive a VLP or an IMN for internal fixation. Functional outcomes (Quick Disabilities of the Arm, Shoulder, and Hand, Michigan Hand Questionnaire), radiographic measurements (ulnar variance, radial height, inclination, and volar tilt), and range of motion were assessed until final follow-up at 2 years after surgery. Narcotic pain medication use was documented for 5 weeks following surgery. RESULTS: There were 2 groups of 30 patients with IMN (mean age, 55 ± 14 y) or VLP (mean age, 55 ± 16 y) with similar demographics and comorbidities. Patients with IMN regained extension earlier but had similar range of motion to patients with VLP at final follow-up. There was similar improvement in Michigan Hand Questionnaire, Quick Disabilities of the Arm, Shoulder, and Hand, and strength between groups. Five weeks after surgery, fewer IMN patients required narcotic pain medication (13%) than VLP patients (33%). Radiographic outcomes were similar at final follow-up. There were 3 failures with IMN versus 1 failure with VLP. All 10 employed patients with IMN returned to previous work compared with 10 of the 12 employed patients with VLP. Time to return to work was similar for both groups. CONCLUSIONS: In a cohort of similar patients, IMN and VLP provided comparable improvement in functional and radiographic outcomes. Patients with IMN required less narcotic pain medication after surgery than VLP patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

Effects of patellofemoral overstuffing on knee flexion and patellar kinematics following total knee arthroplasty: a cadaveric study.

PURPOSE: The purpose of this study was to test the hypothesis that overstuffing the patellofemoral joint during total knee arthroplasty (TKA) would decrease passive knee flexion and alter patellar kinematics during knee flexion. METHODS: Ten cadaveric knees were implanted with cruciate-retaining TKAs, and the patellofemoral joint was overstuffed in 2-mm increments with custom-augmented patellar prostheses (+2 mm through +8 mm). Changes to knee flexion, patellar shift, tilt and rotation were measured with an imageless optical-tracking computer navigation system. RESULTS: Knee flexion decreased an average 1.2° with each additional 2 mm of patellar thickness. Compared with control TKA (+0 mm), no significant decrease in knee flexion was detected until the patellofemoral joint was overstuffed with the +8-mm patellar prosthesis. Kinematic tracking data showed significantly greater lateral shift of patella with the +6- and +8-mm prostheses and significantly greater lateral tilt with the +8-mm prosthesis. Overstuffing had no appreciable effect on patellar rotation. CONCLUSIONS: Passive knee flexion after TKA is significantly reduced when overstuffing the patellofemoral joint by +8 mm, and patellofemoral kinematics are altered when overstuffing the joint by +6 mm. These results demonstrate the relatively modest effects of patellofemoral overstuffing on knee flexion and patellar tracking kinematics after TKA.

Age-related changes affect rat rotator cuff muscle function.

BACKGROUND: The influence of age on rotator cuff function and muscle structure remains poorly understood. We hypothesize that normal aging influences rotator cuff function, muscle structure, and regulatory protein expression in an established rat model of aging. METHODS: Seventeen rats were obtained from the National Institute on Aging. The supraspinatus muscles in 11 middle-aged (12 months old) and 6 old (28 months old) rats were studied for age-related changes in rotator cuff neuromuscular function by in vivo muscle force testing and electromyography (EMG). Changes in muscle structure and molecular changes were assessed with quantitative immunohistochemistry for myogenic determination factor 1 (MyoD) and myogenic factor 5 (Myf5) expression. RESULTS: Old animals revealed significantly decreased peak tetanic muscle force at 0.5 N and 0.7 N preload tension (P < .05). The age of the animal accounted for 20.9% of variance and significantly influenced muscle force (P = .026). Preload tension significantly influenced muscle force production (P < .001) and accounted for 12.7% of total variance. There was regional heterogeneity in maximal compound motor action potential (CMAP) amplitude in the supraspinatus muscle; the proximal portion had a significantly higher CMAP than the middle and distal portions (P < .05). The expression of muscle regulatory factors MyoD and Myf5 was significantly decreased in old animals compared with middle-aged animals (P < .05). CONCLUSIONS: The normal aging process in this rat model significantly influenced contractile strength of the supraspinatus muscle and led to decreased expression of muscle regulatory factors. High preload tensions led to a significant decrease in force production in both middle-aged and old animals.

Depression State Correlates with Functional Recovery Following Elective Lumbar Spine Fusion.

OBJECTIVE: To determine how depression state impacts postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores and achievement of minimum clinically important difference (MCID) following lumbar fusion. Depression has been shown to negatively impact outcomes following numerous orthopedic surgeries. Situational and major clinical depression can differentially affect postoperative outcomes. METHODS: Adult patients undergoing elective 1-3 level lumbar fusion were reviewed. Patients with a formal diagnosis of major depression were classified as "clinically depressed" whereas patients with at least "mild" PROMIS Depression scores in the absence of formal depression diagnosis were deemed "situationally depressed." analysis of variance testing was used to assess differences within and between groups. Multivariate regression was used to identify features associated with the achievement of MCID. RESULTS: Two hundred patients were included. The average age was 65.9 ± 12.2 years. 75 patients (37.5%) were nondepressed, 66 patients (33.0%) were clinically depressed, and 59 patients (29.5%) were situationally depressed. Situationally depressed patients had worse preoperative physical function (PF) and pain interference (PI) scores and were more likely to have severe symptoms (P = 0.001, P = 0.001). All groups improved significantly from preoperative baseline scores. All groups met MCID PF at different rates, with highest proportion of situationally depressed reaching this metric (P = 0.03). Rates of achieving MCID PI were not significantly different between groups (P = 0.47). Situational depression was predictive of achieving MCID PF (P = 0.002) but not MCID PI. CONCLUSIONS: Our study investigated the relationship between depression and postoperative PROMIS scores and identified situationally depressed patients as having the worst preoperative impairment. Despite this, the situationally depressed cohort had the highest likelihood of achieving MCID PF, suggestive of a bidirectional relationship between lumbar degenerative disease and subclinical, situational depression. These findings may help guide preoperative counseling on expectations, and patient selection.

Arthroscopic subacromial decompression improved outcomes in situationally depressed patients compared to clinically depressed or nondepressed patients.

Background: The purpose of this study is to evaluate patient reported outcomes after arthroscopic extensive débridement of the shoulder with subacromial decompression (SAD) for subacromial impingement using the Patient-Reported Outcomes Measurement Information System (PROMIS) system and evaluate if depression (Dep) (clinical or situational) impacts patients achieving a Minimal Clinically Important Difference (MCID). Methods: Preoperative PROMIS Physical function (PF), Mood, and Dep scores were obtained at the closest date prior to arthroscopic rotator cuff repair and postoperative scores were collected at every clinical visit thereafter. Final PROMIS score used for data analysis was determined by the patients final PROMIS value between 90 to 180 days. Clinical Dep was determined by patients having a formal diagnosis of "Depression or Major Depressive Disorder" at the time of their surgery. Situationally depressed patients, those without a formal diagnosis yet exhibited symptomatic depressive symptoms, were classified by having a PROMIS-Dep cutoff scores larger than 52.5. Results: A total of 136 patients were included for final statistical analysis. 13 patients had a clinical but not situational diagnosis of Dep, 86 patients were identified who had no instance of clinical or situational Dep (nondepressed). 35 patients were situationally depressed. All three cohorts demonstrated a significant improvement in postoperative PROMIS Dep, PI, and PF score relative to their preoperative value (P = .001). Situationally depressed patients achieved greater delta PROMIS-Dep compared to patients with major depressive disorder. Depressed patients had a higher chance of achieving MCID for PROMIS-Dep compared to nondepressed patients (P = .01). Logistic regression analysis demonstrated that underlying Dep did not alter the odds of obtaining MCID compared to nondepressed patients. Nonsmoking patients had significantly greater odds of achieving MCID for PF (P = .02). Discussion: Patients improved after undergoing SAD regardless of underlying Dep or depressive symptoms. Depressed patients exhibited greater change in PROMIS scores compared to nondepressed patients. Smoking remains a risk factor for postoperative outcomes in patients undergoing SAD for subacromial impingement. Identifying and counseling patients with underlying depressive symptoms without a formal major depressive disorder diagnosis may lead to improved outcomes. These findings may help guide clinicians in deciding who would benefit the most from this procedure.

The science of rotator cuff tears: translating animal models to clinical recommendations using simulation analysis.

PURPOSE: The purpose of this article is to review basic science studies using various animal models for rotator cuff research and to describe structural, biomechanical, and functional changes to muscle following rotator cuff tears. The use of computational simulations to translate the findings from animal models to human scale is further detailed. METHODS: A comprehensive review was performed of the basic science literature describing the use of animal models and simulation analysis to examine muscle function following rotator cuff injury and repair in the ageing population. RESULTS: The findings from various studies of rotator cuff pathology emphasize the importance of preventing permanent muscular changes with detrimental results. In vivo muscle function, electromyography, and passive muscle-tendon unit properties were studied before and after supraspinatus tenotomy in a rodent rotator cuff injury model (acute vs chronic). Then, a series of simulation experiments were conducted using a validated computational human musculoskeletal shoulder model to assess both passive and active tension of rotator cuff repairs based on surgical positioning. CONCLUSION: Outcomes of rotator cuff repair may be improved by earlier surgical intervention, with lower surgical repair tensions and fewer electromyographic neuromuscular changes. An integrated approach of animal experiments, computer simulation analyses, and clinical studies may allow us to gain a fundamental understanding of the underlying pathology and interpret the results for clinical translation.

Age-related degenerative functional, radiographic, and histological changes of the shoulder in nonhuman primates.

BACKGROUND: Nonhuman primates have similar shoulder anatomy and physiology compared to humans, and may represent a previously underutilized model for shoulder research. This study sought to identify naturally occurring bony and muscular degeneration in the shoulder of nonhuman primates and to assess relationships between structural and functional aspects of the shoulder and measures of physical function of the animals. We hypothesized that age-related degenerative changes in the shoulders of nonhuman primates would resemble those observed in aging humans. METHODS: Middle-aged (n = 5; ages 9.4-11.8 years) and elderly (n = 6; ages 19.8-26.4 years) female vervet monkeys were studied for changes in mobility and shoulder function, and radiographic and histologic signs of age-related degeneration. RESULTS: Four out of 6 (4/6) elderly animals had degenerative changes of the glenoid compared to 0/5 of the middle-aged animals (P = .005). Elderly animals had glenoid retroversion, decreased joint space, walked slower, and spent less time climbing and hanging than middle-aged vervets (P < .05). Physical mobility and shoulder function correlated with glenoid version angle (P < .05). Supraspinatus muscles of elderly animals were less dense (P = .001), had decreased fiber cross-sectional area (P < .001), but similar amounts of nuclear material (P = .085). Degenerative rotator cuff tears were not observed in any of the eleven animals. DISCUSSION AND CONCLUSION: The vervet monkey naturally undergoes age-related functional, radiographic and histological changes of the shoulder, and may qualify as an animal model for selected translational research of shoulder osteoarthritis.

Rotator cuff injuries in professional and recreational athletes.

Professional and recreational athletes involved in contact sports and sports with repetitive overhead motion are at increased risk for rotator cuff tears. Shoulder anatomy, pathology, and biomechanics place unique stress on the rotator cuff tendons during sports activity. Athletes demand effective treatment to quickly return to elite competition. A PubMed search assessed treatment options providing expedited recovery time and return to competition. Twelve of 231 articles fit the objective criteria; 90.5% of professional contact athletes, 40% of professional overhead athletes, and 83.3% of recreational athletes fully recovered following rotator cuff tear surgical repair. Prompt surgical treatment for full-thickness rotator cuff tears may be appropriate for contact athletes and recreational overhead athletes. Although professional overhead athletes have low recovery rates, surgical repair of full-thickness rotator cuff tears may still be indicated. The authors propose a treatment algorithm based on the limited literature (mainly level 4 and 5 evidence).