The Effect of Lateralization and Distalization After Grammont-Style Reverse Total Shoulder Arthroplasty.

BACKGROUND: The purpose of this study is to evaluate the relationship between multiple radiographic measures of lateralization and distalization and clinical outcome scores after reverse total shoulder arthroplasty (RTSA). METHODS: We retrospectively evaluated all RTSAs performed by the senior author between January 1, 2007, and November 1, 2017. We then evaluated the visual analog scale for pain (VAS pain), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) scores and complication and reoperation rates at a minimum of 2-year follow-up. We measured preoperative and postoperative (2-week) radiographs for the lateralization shoulder angle (LSA), the distalization shoulder angle (DSA), lateral humeral offset (LHO), and distance from glenoid to lateral aspect of the greater tuberosity (GLAGT). A multivariable analysis was performed evaluating the effect of the postoperative radiographic measurements on final patient reported outcomes (ASES scores, SST, VAS pain). RESULTS: The cohort included 216 shoulders from unique patients who had patient reported outcome scores available at a minimum of 2-year follow-up (average, 4.0±1.9 years) for a total follow-up rate of 70%. In the multivariable models, more lateralization (LSA) was associated with worse final ASES scores -0.52 (95% CI: -0.88 to -0.17; p=0.004), and more distalization (DSA) was associated with better final ASES scores 0.40 (95% CI: 0.11, 0.69; p=0.007). More lateralization (LSA) was associated with worse final SST scores -0.06 (95% CI: -0.11, -0.003; p=0.039). Finally, greater distalization (DSA) was associated with lower final VAS pain scores, Ratio = 0.98 (95% CI: 0.96, 1.00; p=0.021). CONCLUSION: Greater distalization and less lateralization are associated with better function and less pain after Grammont-style RTSA. If utilizing a Grammont-style implant, remaining consistent with Grammont's principles of implant placement will afford better final clinical outcomes.

Implementation and Clinical Outcomes of Blood Flow Restriction Training on Adults With Cerebral Palsy: A Case Series.

BACKGROUND AND PURPOSE: Cerebral palsy (CP) is a congenital neurological disorder that causes musculoskeletal weakness and biomechanical dysfunctions. Strength training guidelines recommend at least 70% of 1-repetition maximum to increase muscle strength and mass. However, individuals with CP may not tolerate such high exercise intensity. Blood flow restriction (BFR) can induce similar gains in strength and muscle mass using loads as low as 20% to 30% 1-repetition maximum. This case series described the safety, feasibility, and acceptability of BFR in adults with CP and examined changes in muscle mass and strength. CASE DESCRIPTION: Three male participants with gross motor function classification system level 3 CP underwent strength training using a periodized 8-week BFR protocol. Outcomes included: Safety via blood pressure during and post-BFR exercises in addition to adverse event tracking; Feasibility via number of support people and time-duration of BFR exercises; Acceptability via rate of perceived discomfort (0-10) and qualitative interviews; Muscle Mass via ultrasonographic cross-sectional area of the quadriceps and hamstring; and Strength via (1) 3-repetition maximum in the leg press and knee extension, (2) isometric knee flexor and extensor muscle force measured with a hand-held dynamometer, and (3) 30-second sit-to-stand test. INTERVENTION: Participants replaced 2 exercises from their current regimen with seated knee extension and leg press exercises using progressively higher limb occlusion pressure and exercise intensity. Limb occlusion pressure started at 60%, by week 4 progressed to 80%, and then remained constant. The exercise repetition scheme progressed from fixed nonfailure repetition sets to failure-based repetition sets. OUTCOMES: Blood pressure never exceeded safety threshold, and no adverse events were reported. The BFR training was time-consuming and resource-intensive, but well-tolerated by participants (rate of perceived discomfort with a mean value of 5.8, 100% protocol adherence). Strength, as measured by 3-repetition maximum testing and 30-second sit-to-stand test, increased, but isometric muscle force and muscle mass changes were inconsistent. DISCUSSION: Blood flow restriction may be an effective means to increase strength in adults with CP who cannot tolerate high-intensity resistance training. Future research should compare BFR to traditional strength training and investigate mediators of strength changes in this population. VIDEO ABSTRACT AVAILABLE: for more insights from the authors (see the Video, Supplemental Digital Content available at: http://links.lww.com/JNPT/A473).

Primary care barriers and facilitators to nonpharmacologic treatments for low back pain: A qualitative pilot study.

BACKGROUND: Clinical practice guidelines encourage primary care providers (PCPs) to recommend nonpharmacologic treatment as first-line therapy for low back pain (LBP). However, the determinants of nonpharmacologic treatment use for LBP in primary care remain unclear, particularly in low-income settings. OBJECTIVE: To pilot a framework-informed interview guide and codebook to explore determinants of nonpharmacologic treatment use in primary care. METHODS: In this qualitative interview study, we enrolled PCPs and community health workers (CHWs) from four primary care clinics at a safety net hospital. A semistructured interview guide informed by the Consolidated Framework for Implementation Research (CFIR) guided inquiry on barriers/facilitators to nonpharmacologic treatments for LBP (eg, acupuncture, chiropractic care, physical therapy). We included questions on whether current CHW roles may address barriers to nonpharmacologic treatment use. Interviews were audio-recorded, transcribed verbatim, and independently coded by four investigators. An a priori codebook composed of CFIR determinants and known CHW roles guided deductive content analysis to identify major themes. RESULTS: Eight individuals (six PCPs, two CHWs; age range: 32-51 years, five female) participated in hour-long interviews. Half had worked at the hospital for ≥15 years and all reported seeing patients with LBP (range: 2-20 patients per week). All participants identified the following CFIR factors as barriers/facilitators: nonpharmacologic treatment characteristics (perceived cost, relative advantage compared to other treatments); outer setting (patient needs/resources, limited connections with community-based nonpharmacologic treatment) and PCP characteristics (attitudes/beliefs about nonpharmacologic treatments). Although participants indicated several CHW roles could be adapted to address barriers (eg, care coordination, resource linking, case management), other roles seemed less feasible (eg, targeted health education) in our health care system. CONCLUSIONS: Preliminary insight on key determinants of nonpharmacologic treatments for LBP should be further examined in large multisite studies. Future studies may also determine whether a CHW-led strategy can improve nonpharmacologic treatment access and clinical outcomes in primary care.

A Cluster Analysis of Initial Primary Care Orders for Patients with Acute Low Back Pain.

PURPOSE: Primary care physicians (PCPs) often face a complex intersection of patient expectations, evidence, and policy that influences their care recommendations for acute low back pain (aLBP). The purpose of this study was to elucidate patterns of PCP orders for patients with aLBP, identify the most common patterns, and describe patient clinical and demographic characteristics associated with patterns of aLBP care. METHODS: This prospective cohort study included 9574 aLBP patients presenting to 1 of 77 primary care practices in 4 geographic locations in the United States. We performed a cluster analysis of PCP orders extracted from electronic health records within the first 21 days of an initial visit for aLBP. RESULTS: 1401 (15%) patients did not receive a PCP order related to back pain within the first 21 days of their initial visit. These patients predominantly had aLBP without leg pain, less back-related disability, and were at low-risk for persistent disability. Of the remaining 8146 patients, we found 4 distinct order patterns: combined nonpharmacologic and first-line medication (44%); second-line medication (39%); imaging (10%); and specialty referral (7%). Among all patients, 29% received solely 1 order from their PCP. PCPs more often combined different guideline concordant and discordant orders. Patients with higher self-reported disability and psychological distress were more likely to receive guideline discordant care. CONCLUSION: Guideline discordant orders such as steroids and NSAIDS are often combined with guideline recommended orders such as physical therapy. Further defining patient, clinician, and health care setting characteristics associated with discordant care would inform targeted efforts for deimplementation initiatives.

Three-month Delay in Rotator Cuff Repair: 2-year Follow-up.

INTRODUCTION: This study examined 2-year outcomes of patients who underwent delayed rotator cuff repair (RCR) compared with those who underwent RCR without delay. METHODS: In this prospective comparative study, two groups were formed: (1) patients planning RCR during a 6-week elective surgery ban and (2) patients undergoing RCR at least 6 weeks after the ban. The Simple Shoulder Test, American Shoulder and Elbow Surgeon score, and visual analog scale for pain were collected preoperatively and at 2 years postoperatively. Magnetic resonance imaging assessed healing 6 months postoperatively. RESULTS: With a 93.3% 2-year follow-up (13/15 delay group, 15/15 control), there was an 87-day difference in presentation to surgery (P = 0.001), with no significant preoperative demographic or tear characteristic differences between groups. Intraoperatively, there were no differences between groups in repair characteristics. Preoperative versus postoperative differences in American Shoulder and Elbow Surgeon score (P < 0.001), visual analog scale (P < 0.001), and Simple Shoulder Test scores (P < 0.001) were significant but not between groups (P = 0.650, 0.586, 0.525). On MRI, 58% in the delay group and 85% in the control group had healed (P = 0.202). DISCUSSION: Although a 3-month delay showed no statistically significant effect on outcomes, the delay group had an approximately 27% higher failure rate. Thus, although a 3-month period of nonsurgical treatment before RCR may be reasonable, larger studies are warranted for definitive conclusions.

Biomechanical comparison of suture bridge rotator cuff repair with and without dermal allograft pledgets.

BACKGROUND: One method to augment rotator cuff repair is to pass dermal allograft pledgets along the sutures that bridge from the medial to the lateral row. It remains unclear whether this augmentation method alters repair biomechanics. METHODS: This was a controlled laboratory study. After an a priori power analysis, 9 pairs of rotator cuffs underwent double-row suture bridge rotator cuff repair, half randomized to augmentation with dermal allograft pledgets passed along the suture bridge sutures. Repairs were then mounted on a material testing system and loaded cyclically 500 cycles to measure applied force and displacement. Repairs then underwent ultimate failure testing, and stiffness, ultimate failure force, and ultimate failure displacement were measured. Paired t tests were performed to compare between groups. RESULTS: There were no differences between groups in construct gapping with cyclic loading after 500 cycles (P = .885). There were no differences between the augmented and control groups in yield force (103.5 ± 5.0 vs. 101.4 ± 5.9 N, respectively, P = .183), stiffness (94.2 ± 13.9 vs. 90.9 ± 13.8, P = .585), or ultimate failure force (255.3 ± 65.8 vs. 285.3 ± 83.2, P = .315). There were no differences between groups in failure modes, with most specimens failing by cuff tissue tearing within or medial to the construct. CONCLUSION: The addition of dermal allograft pledgets does not positively or negatively influence the time-zero biomechanical characteristics of double-row suture bridge rotator cuff repair.

Inlay vs. onlay humeral components in reverse total shoulder arthroplasty: a biorobotic shoulder simulator study.

BACKGROUND: Both inlay and onlay humeral implants are available for reverse total shoulder arthroplasty (rTSA), but biomechanical data comparing these components remain limited. This study investigated the effects of inlay and onlay rTSA humeral components on shoulder biomechanics using a biorobotic shoulder simulator. METHODS: Twenty fresh-frozen cadaveric shoulders were tested before and after rTSA with either an inlay or onlay humeral implant. Comparisons were performed between the most commonly implanted configurations for each implant (baseline) and with a modification to provide equivalent neck-shaft angles (NSAs) for the inlay and onlay configurations. Specimens underwent passive range-of-motion (ROM) assessment with the scapula held static, and scapular-plane abduction was performed, driven by previously collected human-subject scapulothoracic and glenohumeral kinematics. Passive ROM glenohumeral joint angles were compared using t tests, whereas muscle force and excursion data during scapular-plane elevation were evaluated with statistical parametric mapping and t tests. RESULTS: Maximum passive elevation was reduced for the inlay vs. onlay humeral components, although both implants caused reduced passive elevation vs. the native joint. Inlay rTSA also demonstrated reduced passive internal rotation at rest and increased external rotation at 90° of humerothoracic elevation vs. the native joint. All preoperative planning estimates of ROM differed from experiments. Rotator cuff forces were elevated with an onlay vs. inlay humeral implant, but simulated muscle excursions did not differ between systems. Compared with the native joint, rotator cuff forces were increased for both inlay and onlay implants and deltoid forces were reduced for inlay implants. Muscle excursions were dramatically altered by rTSA vs. the native joint. Comparisons of inlay and onlay humeral implants with equivalent NSAs were consistent with the baseline comparisons. CONCLUSIONS: Rotator cuff forces required to perform scapular-plane abduction increase following rTSA using both inlay and onlay implants. Rotator cuff forces are lower with inlay implants compared with onlay implants, although inlay implants also result in reduced passive-elevation ROM. Deltoid forces are lower with inlay implants in comparison to the native joint but not with onlay implants. The differences between inlay and onlay components are largely unaffected by NSA, indicating that these differences are inherent to the inlay and onlay designs. In those patients with an intact rotator cuff, decreased rotator cuff forces to perform abduction with an inlay humeral implant compared with an onlay implant may promote improved long-term outcomes owing to reduced deltoid muscle fatigue when using an inlay implant.

Revision Subpectoral Biceps Tenodesis Demonstrates a High Patient Satisfaction and Good Functional Outcomes.

Purpose: To clinically evaluate a subset of patients who underwent a revision subpectoral biceps tenodesis for a clinically failed proximal biceps tenodesis. Methods: This is a retrospective case series of patients with at least 2-year follow-up who had undergone a revision biceps tenodesis after clinical failure of a proximal biceps tenodesis between January 2008 and February 2020 by a single surgeon. Patients who underwent concomitant procedures, such as revision cuff repair, were excluded. Patients with a minimum of 2 years duration status postrevision subpectoral tenodesis were contacted for informed consent and outcome data, which included Simple Shoulder Test, American Shoulder and Elbow Surgeons score, visual analog scale for pain, and subjective reporting of arm weakness and satisfaction. Results: Fourteen patients were initially identified as meeting inclusion criteria with a minimum 2-year follow-up achieved for 11 of 14 patients (78.5% follow-up). The mean follow-up time was 8.1 years (range, 2.7-14.8 years). After the primary biceps tenodesis, a mean of 8.0 ± 9.6 months passed before the revision subpectoral biceps tenodesis was performed. The average postoperative active forward elevation and adducted external rotation were 159 ± 7° and 47 ± 17°, respectively. The mean ± standard deviation (range) follow-up American Shoulder and Elbow Surgeons score was 79 ± 23 (30-100), Simple Shoulder Test was 11 ± 2 (7-12), and visual analog scale for pain was 2.6 ± 2.8 (0-9). All 11 patients reported being satisfied with their operation and would elect to have the operation again. Conclusions: Revision subpectoral biceps tenodesis is a viable procedure for addressing patients with persistent pain following initial proximal biceps tenodesis. Although some persistent pain is common, revision subpectoral biceps tenodesis demonstrates a high patient satisfaction and good functional outcomes. Level of Evidence: Level IV, therapeutic case series.

Therapeutic Hypothermia for Refractory Hypoxemia on Venovenous Extracorporeal Membrane Oxygenation: An In Silico Study.

Patients with respiratory failure may remain hypoxemic despite treatment with venovenous extracorporeal membrane oxygenation (VV-ECMO). Therapeutic hypothermia is a potential treatment for such hypoxia as it reduces cardiac output ( ) and oxygen consumption. We modified a previously published mathematical model of gas exchange to investigate the effects of hypothermia during VV-ECMO. Partial pressures were expressed as measured at 37°C (α-stat). The effect of hypothermia on gas exchange was examined in four clinical scenarios of hypoxemia on VV-ECMO, each with different physiological derangements. All scenarios had arterial partial pressure of oxygen (PaO 2 ) ≤ 46 mm Hg and arterial oxygen saturation of hemoglobin (SaO 2 ) ≤ 81%. Three had high with low extracorporeal blood flow to ratio ( ). The problem in the fourth scenario was recirculation, with normal . Cooling to 33°C increased SaO 2 to > 89% and PaO 2 to > 50 mm Hg in all scenarios. Mixed venous oxygen saturation of hemoglobin as % ( ) increased to > 70% and mixed venous partial pressure of oxygen in mm Hg ( ) increased to > 34 mm Hg in scenarios with low . In the scenario with high recirculation, and increased, but to < 50% and < 27 mm Hg, respectively. This in silico study predicted cooling to 33°C will improve oxygenation in refractory hypoxemia on VV-ECMO, but the improvement will be less when the problem is recirculation.

Longitudinal Development of Sprint Performance and Force-Velocity-Power Characteristics: Influence of Biological Maturation.

ABSTRACT: Edwards, T, Weakley, J, Banyard, HG, Cripps, A, Piggott, B, Haff, GG, and Joyce, C. Longitudinal development of sprint performance and force-velocity-power characteristics: influence of biological maturation. J Strength Cond Res 37(11): 2178-2184, 2023-This study was designed to investigate the influence of biological maturation on the longitudinal development of sprint performance. Thirty-two subjects performed 2 assessments of maximal sprint performance that were separated by 18 months. Each sprint assessment was measured through a radar gun that collected instantaneous velocity with the velocity-time data used to derive sprint times and force-velocity-power characteristics. The biological maturity of each subject was assessed using a predictive equation, and subjects were grouped according to predicted years from peak height velocity (circa-PHV: -1.0 to 1.0; post-PHV: >1.0). A 2 × 2 mixed model analysis of variance was used to assess group × time interactions, and paired t -tests were used to assess the longitudinal changes for each maturity group. No significant group × time interactions were observed for any sprint time or force-velocity-power characteristic. The circa-PHV group experienced significant within-group changes in maximal theoretical velocity (6.35 vs. 5.47%; effect size [ES] = 1.26 vs. 0.52) and 5-m sprint time (-3.63% vs. -2.94%; ES = -0.64 vs. -0.52) compared with the post-PHV group. There was no significant change in the magnitude of relative theoretical maximum force in either group; however, both the circa-PHV and post-PHV groups significantly improved the orientation of force production at the start of the sprint (RFmax [4.91 vs. 4.46%; ES = 0.79 vs. 0.74, respectively]). Considering these findings, it is recommended that practitioners adopt training methods aimed to improve relative lower-limb force production, such as traditional strength training and sled pulling and pushing, to improve sprint performance and relative theoretical maximum force.

Progression of symptomatic bilateral rotator cuff disease.

Background: Prior studies have demonstrated that conservatively treated rotator cuff tears and rotator cuff tendinopathy may continue to progress. It is unclear whether that rate of progression differs between sides in patients with bilateral disease. This study evaluated the likelihood of progression of rotator cuff disease as confirmed via magnetic resonance imaging (MRI) in individuals with symptomatic bilateral pathology, treated conservatively for a minimum of 1 year. Methods: We identified patients with bilateral rotator cuff disease confirmed via MRI within the Veteran's Health Administration electronic database. A retrospective chart review via the Veteran's Affairs electronic medical record was performed. Progression was determined using 2 separate MRIs with a minimum of 1 year apart. We defined progression as (1) a progression from tendinopathy to tearing, (2) an increase from partial-thickness to full-thickness tearing, or (3) an increase in tear retraction or tear width of at least 5 mm. Results: Four hundred eighty MRI studies from 120 Veteran's Affair patients with bilateral, conservatively treated rotator cuff disease were evaluated. Overall, 42% (100/240) of rotator cuff disease had progressed. No significant difference was found between progression of right vs. left rotator cuff pathology, with right shoulder pathology progressing at a rate of 39% (47/120), while left shoulder disease progressed at a rate of 44% (53/120). The likelihood of disease progression was associated with less initial tendon retraction (P value = .016) and older age (P value = .025). Conclusions: Rotator cuff tears are no more likely to progress on the right, as compared to the left side. Older age and less initial tendon retraction were found to be predictors of disease progression. These suggest that higher activity level may not associate with greater progression of rotator cuff disease. Future prospective studies evaluating progression rates between dominant vs. nondominant shoulders are warranted.

Abnormal Laboratory Values for Metabolic and Hormonal Syndromes Are Prevalent Among Patients Undergoing Rotator Cuff Repair.

Purpose: To determine the prevalence of systemic laboratory abnormalities among patients undergoing rotator cuff repair (RCR). Methods: Patients who underwent RCR at the authors' institution for 1 year between October 2021 to September 2022 were retrospectively identified. Preoperative laboratory values, including serum sex hormones, vitamin D, hemoglobin A1C, and a lipid panel, were obtained as part of our routine practice during the study period. Demographics and tear characteristics were compared in patients with laboratory data and those without. For included patients with laboratory data, mean laboratory values and percentage of patients with abnormal laboratory values were recorded. Results: During a 1-year period of time, 135 RCRs were performed, of which preoperative labs were obtained on 105. Of these, 67% were sex hormone deficient, 36% were vitamin D deficient, 45% had an abnormal hemoglobin A1C, and 64% had an abnormal lipid panel. In total 4% had "normal" labs. Conclusions: In this retrospective study, sex hormone deficiency is highly prevalent among patients undergoing RCR. Nearly all patients undergoing RCR have systemic laboratory abnormalities involving either sex hormone deficiency, vitamin D deficiency, dyslipidemia, and/or prediabetes. Level of Evidence: Level IV, prognostic case series.

The Pleiotropic Effects of Carbohydrate-Mediated Growth Rate Modifications in Bifidobacterium longum NCC 2705.

Bifidobacteria are saccharolytic bacteria that are able to metabolize a relatively large range of carbohydrates through their unique central carbon metabolism known as the "bifid-shunt". Carbohydrates have been shown to modulate the growth rate of bifidobacteria, but unlike for other genera (e.g., E. coli or L. lactis), the impact it may have on the overall physiology of the bacteria has not been studied in detail to date. Using glucose and galactose as model substrates in Bifidobacterium longum NCC 2705, we established that the strain displayed fast and slow growth rates on those carbohydrates, respectively. We show that these differential growth conditions are accompanied by global transcriptional changes and adjustments of central carbon fluxes. In addition, when grown on galactose, NCC 2705 cells were significantly smaller, exhibited an expanded capacity to import and metabolized different sugars and displayed an increased acid-stress resistance, a phenotypic signature associated with generalized fitness. We predict that part of the observed adaptation is regulated by the previously described bifidobacterial global transcriptional regulator AraQ, which we propose to reflect a catabolite-repression-like response in B. longum. With this manuscript, we demonstrate that not only growth rate but also various physiological characteristics of B. longum NCC 2705 are responsive to the carbon source used for growth, which is relevant in the context of its lifestyle in the human infant gut where galactose-containing oligosaccharides are prominent.

Patients With Mild Osteoarthritis Are Less Likely to Achieve a Clinically Important Improvement in Pain or Function After Anatomic Total Shoulder Arthroplasty.

BACKGROUND: The severity of glenohumeral osteoarthritis (OA) as demonstrated by preoperative radiographs and patient-reported pain plays an important role in the indication for anatomic total shoulder arthroplasty (aTSA). In hip and knee research, data about the effect of the severity of preoperative radiographic OA on the outcome of total joint arthroplasty have been mixed. For shoulder replacement, we are unsure of the effects of radiographic severity on outcomes. QUESTIONS/PURPOSES: This study investigated whether the preoperative radiographic severity of glenohumeral OA is associated with improvement in pain and function after aTSA. We asked, (1) does the severity of glenohumeral OA correlate with improvement in patient-reported outcomes after TSA (delta American Shoulder and Elbow Surgeons score [postoperative-preoperative], delta Single Assessment Numeric Evaluation, delta Simple Shoulder Test, and delta VAS)? (2) Is having mild osteoarthritis associated with not meeting the minimum clinically important differences in preoperative and postoperative American Shoulder and Elbow Surgeons scores? METHODS: An institutional query of patients who underwent aTSA for OA was performed between January 2015 and December 2018. A total of 1035 patients were eligible; however, only patients with adequate preoperative radiographs and patient-reported outcome measures collected preoperatively and at a minimum of 2 years postoperatively were included. Patients with proximal humerus fractures, inflammatory arthropathy, cuff tear arthropathy, prior ipsilateral rotator cuff repair, brachial plexus injury or neuromuscular disorder, workers compensation, periprosthetic joint infection, or revision surgery within 2 years were excluded. Patient characteristics, comorbidities, and prior shoulder surgery were recorded. The severity of OA was classified based on the modified Samilson-Prieto and Walch classification. The association between Samilson-Prieto grade and patient-reported outcome measures (American Shoulder and Elbow Surgeons Score, Single Assessment Numeric Evaluation, Simple Shoulder Test, and VAS score) was evaluated. Radiographic characteristics, patient demographics, comorbidities, and prior surgery were also evaluated for the potential risk of not achieving improvement in the minimum clinically important difference (16.1) with respect to the American Shoulder and Elbow Surgeons score. The American Shoulder and Elbow Surgeons score is scored 0 to 100, with higher scores representing less pain and better function. A total of 206 patients (20% of those eligible) with a mean follow-up of 2.3 years were included. Twenty-three patients had Samilson-Prieto Grade I, 38 had Grade II, 57 had Grade III, and 88 had Grade IV. RESULTS: There were no differences in improvements (delta) between the groups and between patient-reported outcome scores (American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation, Simple Shoulder Test, and VAS). Compared with patients with more severe osteoarthritis (Samilson-Prieto Grades II, III, and IV), a higher proportion of patients with less severe osteoarthritis (Grade I) did not exceed the minimum clinical important difference for the American Shoulder and Elbow Surgeons score (22% [five of 23] versus 4% [seven of 183]; odds ratio 0.14 [95% confidence interval 0.04 to 0.520]; p = 0.006). CONCLUSION: The improvement in patient-reported outcome measure scores was similar regardless of radiographic severity after aTSA. Surgeons should use caution when recommending surgery to patients with less severe OA because a higher percentage did not improve, based on the minimum clinically important difference. LEVEL OF EVIDENCE: Level III, therapeutic study.

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

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

Editorial Commentary: Rotator Cuff Repair in Patients With Diabetes: Stricter Glycemic Control for the First 6 Months Is Associated With Better Healing.

Retear rates after arthroscopic rotator cuff repair continue to be unacceptably high. Of the known risk factors for failure of rotator cuff repair, many are nonmodifiable. Poor glycemic control in patients with diabetes in the first 3 to 6 months after arthroscopic rotator cuff repair is associated with a lower healing rate. This represents a modifiable risk factor that we should routinely address in patients postoperative rotator cuff repair.

Racial and Ethnic Disparities in the Incidence of High-Impact Chronic Pain Among Primary Care Patients with Acute Low Back Pain: A Cohort Study.

OBJECTIVE: We assessed whether race or ethnicity was associated with the incidence of high-impact chronic low back pain (cLBP) among adults consulting a primary care provider for acute low back pain (aLBP). METHODS: In this secondary analysis of a prospective cohort study, patients with aLBP were identified through screening at seventy-seven primary care practices from four geographic regions. Incidence of high-impact cLBP was defined as the subset of patients with cLBP and at least moderate disability on Oswestry Disability Index [ODI >30]) at 6 months. General linear mixed models provided adjusted estimates of association between race/ethnicity and high-impact cLBP. RESULTS: We identified 9,088 patients with aLBP (81.3% White; 14.3% Black; 4.4% Hispanic). Black/Hispanic patients compared to White patients, were younger and more likely to be female, obese, have Medicaid insurance, worse disability on ODI, and were at higher risk of persistent disability on STarT Back Tool (all P < .0001). At 6 months, more Black and Hispanic patients reported high-impact cLBP (30% and 25%, respectively) compared to White patients (15%, P < .0001, n = 5,035). After adjusting for measured differences in socioeconomic and back-related risk factors, compared to White patients, the increased odds of high-impact cLBP remained statistically significant for Black but not Hispanic patients (adjusted odds ration [aOR] = 1.40, 95% confidence interval [CI]: 1.05-1.87 and aOR = 1.25, 95%CI: 0.83-1.90, respectively). CONCLUSIONS: We observed an increased incidence of high-impact cLBP among Black and Hispanic patients compared to White patients. This disparity was partly explained by racial/ethnic differences in socioeconomic and back-related risk factors. Interventions that target these factors to reduce pain-related disparities should be evaluated. CLINICALTRIALS.GOV IDENTIFIER: NCT02647658.

Optimal Settings at Initiation of Veno-Venous Extracorporeal Membrane Oxygenation: An Exploratory In-Silico Study.

The Extracorporeal Life Support Organisation (ELSO) recommends initiating veno-venous extracorporeal membrane oxygenation (ECMO) with sweep gas flow rate () of 2 L/min and extracorporeal circuit blood flow () of 2 L/min. We used an in-silico model to examine the effect on gas exchange of initiating ECMO with different and , and the effect of including 5% in sweep gas. This was done using a set of patient examples, each with different physiological derangements at baseline (before ECMO). When ECMO was initiated following ELSO recommendations in the patient examples with significant hypercapnia at baseline, sometimes fell to < 50% of the baseline , a magnitude of fall associated with adverse neurological outcomes. In patient examples with very low baseline arterial oxygen saturation (), initiation of ECMO did not always increase to > 80%. Initiating ECMO with of 1 L/min and of 4 L/min, or with sweep gas containing 5% , of 2 L/min, and of 4 L/min, reduced the fall in and increased the rise in compared to the ELSO strategy. While ELSO recommendations may suit most patients, they may not suit patients with severe physiological derangements at baseline.