176 research outputs found
Bioresorbable Polylactide Interbody Implants in an Ovine Anterior Cervical Discectomy and Fusion Model: Three-Year Results
Study Design.
In vivo study of anterior discectomy and fusion using a bioresorbable 70:30 poly(l-lactide-co-d,l-lactide) interbody implant in an ovine model.
Objective.
To evaluate the efficacy of the polylactide implant to function as an interbody fusion device, and to assess the tissue reaction to the material during the resorption process.
Summary of Background Data.
The use of polylactide as a cervical interbody implant has several potential advantages when compared with traditional materials. Having an elastic modulus very similar to bone minimizes the potential for stress shielding, and as the material resorbs additional loading is transferred to the developing fusion mass. Although preclinical and clinical studies have demonstrated the suitability of polylactide implants for lumbar interbody fusion, detailed information on cervical anterior cervical discectomy and fusion (ACDF) with polylactide devices is desirable.
Methods.
Single level ACDF was performed in 8 skeletally mature ewes. Bioresorbable 70:30 poly (l-lactide-co-d,l-lactide) interbody implants packed with autograft were used with single-level metallic plates. Radiographs were made every 3 months up to 1 year, and yearly thereafter. The animals were killed at 6 months (3 animals), 12 months (3 animals), and 36 months (2 animals). In addition to the serial plain radiographs, the specimens were evaluated by nondestructive biomechanical testing and undecalcified histologic analysis.
Results.
The bioresorbable polylactide implants were effective in achieving interbody fusion. The 6-month animals appeared fused radiographically and biomechanically, whereas histologic sections demonstrated partial fusion (in 3 of 3 animals). Radiographic fusion was confirmed histologically and biomechanically at 12 months (3 of 3 animals) and 36 months (2 of 2 animals). A mild chronic inflammatory response to the resorbing polylactide implant was observed at both 6 months and 12 months. At 36 months, the operative levels were solidly fused and the implants were completely resorbed. No adverse tissue response was observed in any animal at any time period.
Conclusion.
Interbody fusion was achieved using bioresorbable polylactide implants, with no evidence of implant collapse, extrusion, or adverse tissue response to the material. The use of polylactide as a cervical interbody device appears both safe and effective based on these ACDF animal model results
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Prevalence and risk factors for periprosthetic fracture in older recipients of total hip replacement: a cohort study
Background: The growing utilization of total joint replacement will increase the frequency of its complications, including periprosthetic fracture. The prevalence and risk factors of periprosthetic fracture require further study, particularly over the course of long-term follow-up. The objective of this study was to estimate the prevalence and risk factors for periprosthetic fractures occurring in recipients of total hip replacement. Methods: We identified Medicare beneficiaries who had elective primary total hip replacement (THR) for non-fracture diagnoses between July 1995 and June 1996. We followed them using Medicare Part A claims data through 2008. We used ICD-9 codes to identify periprosthetic femoral fractures occurring from 2006–2008. We used the incidence density method to calculate the annual incidence of these fractures and Cox proportional hazards models to identify risk factors for periprosthetic fracture. We also calculated the risk of hospitalization over the subsequent year. Results: Of 58,521 Medicare beneficiaries who had elective primary THR between July 1995 and June 1996, 32,463 (55%) survived until January 2006. Of these, 215 (0.7%) developed a periprosthetic femoral fracture between 2006 and 2008. The annual incidence of periprosthetic fracture among these individuals was 26 per 10,000 person-years. In the Cox model, a greater risk of periprosthetic fracture was associated with having had a total knee replacement (HR 1.82, 95% CI 1.30, 2.55) or a revision total hip replacement (HR1.40, 95% CI 0.95, 2.07) between the primary THR and 2006. Compared to those without fractures, THR recipients who sustained periprosthetic femoral fracture had three-fold higher risk of hospitalization in the subsequent year (89% vs. 27%, p < 0.0001). Conclusion: A decade after primary THR, periprosthetic fractures occur annually in 26 per 10,000 persons and are especially frequent in those with prior total knee or revision total hip replacements
The national burden of orthopedic injury: Cross-sectional estimates for trauma system planning and optimization
Background: Management of orthopedic injuries is a critical component of comprehensive trauma care. As patterns of injury incidence and recovery change in the face of emerging injury prevention efforts and technologies and an aging US population, assessment of the burden of orthopedic injury is essential to optimize trauma system planning. We sought to estimate the incidence of orthopedic injury requiring emergency orthopedic surgery in the United States.Methods: Using nationally representative samples from the Agency for Healthcare Research and Quality Healthcare Cost and Utilization Project, we estimated the incidence of orthopedic injury, polytrauma with orthopedic injury, and emergency operative orthopedic procedures performed for the management of traumatic injury. We used multivariable logistic regression to identify patient, injury, and hospital characteristics associated with odds of emergency orthopedic surgery.Results: A total of 7,214,915 patients were diagnosed with orthopedic injury in 2013-2014, resulting in 1,167,656 emergency orthopedic surgical procedures. Fall-related injuries accounted for 51% of health care encounters and 61% of emergency orthopedic surgical procedures. Odds of emergency orthopedic surgery were 2.04 times greater for patients with polytrauma, compared with isolated orthopedic injury (P \u3c 0.001).Conclusions: The total burden or orthopedic injury in the United States is substantial, and there is considerable heterogeneity in demand for care and practice patterns in the orthopedic trauma community. Population-based trauma system planning and tailored care delivery models would likely optimize initial treatment, recovery, and health outcomes for orthopedic trauma patients
Mortality and Readmission After Cervical Fracture from a Fall in Older Adults: Comparison with Hip Fracture Using National Medicare Data
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/115960/1/jgs13670.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/115960/2/jgs13670_am.pd
Use of the Adult Myopathy Assessment Tool as a predictor of functional abilities in people with multiple sclerosis
Background: People with multiple sclerosis (PwMS) are at greater risk for decreased muscle performance which may lead to decreased functional abilities. The Kurtzke Expanded Disability Status Scale (EDSS) is commonly used as a disability status rating scale in PwMS. Nevertheless, the EDSS is largely comprised of neurological tests and may not best reflect functional performance. A functional battery such as The Adult Myopathy Assessment Tool (AMAT) may better reflect functional performance. The AMAT was designed to assess both functional strength and endurance in clinical settings. However, the AMAT has not been validated for the assessment of PwMS.
Objective: The purpose of the study was to determine the comparative association of the AMAT and EDSS with measures of strength, fatigability, and functional performance. Methods: Twenty-nine people (mean age 48.6 ±11.2), with a history of MS (EDSS \u3c 7.0) were recruited. Participants completed functional testing (5 times sit to stand and gait speed) and an assessment of disability and functional status using the EDSS and AMAT, respectively. Muscle performance was assessed via a 60 s maximal volitional isometric contraction (MVIC) of the knee extensors using an isokinetic dynamometer, and expressed as fatigability (exhaustion time to 60% of MVIC), peak torque, and peak torque scaled to body weight.
Results:The participants exhibited moderate levels of disability (EDSS, 3.6 ±1.4) and function (AMAT total score, 36.1 ±7.6; AMAT function subscale, 18.2 ±3.3). Peak force was 70.1 kg ±22.0 kg, exhaustion time was 38.4 s ±17.4 s, gait speed was 1.3 m/s ±0.3 m/s, and five time sit to stand was 11.4 s ±4.1 s. The AMAT function subscale was associated with scaled peak torque (r=0.426, p=.021), gait speed (r=0.825, p=0.00), and 5 time sit to stand (r=-0.632, p
Conclusions: The AMAT was more strongly associated with scaled peak torque and functional measures in comparison to the EDSS. This may reflect the observation that relative strength is a better predictor of functional abilities than unadjusted strength measures. Whereas, the stronger association of the EDSS with fatigability may be explained by the pyramidal systems measures within the tool and the well-known association of MS-related fatigue with disability. Based on the results of the study, we suggest clinicians administer the AMAT in addition to the EDSS, to gain insight into functional impairments and assist with formulating a comprehensive plan of care
OrthoPass: Long-term Outcomes following Implementation of an Orthopaedic Patient Handoff Template.
Standardized handoff tools improve communication and patient care; however, their widespread use in surgical fields is lacking. OrthoPass, an orthopaedic adaptation of I-PASS, was developed in 2019 to address handoff concerns and demonstrated sustained improvements across multiple handoff domains over an 18-month period. We sought to characterize the longitudinal effect and sustainability of OrthoPass within a single large residency program 3.5 years after its implementation. This mixed methods study involved electronic handoff review for quality domains in addition to survey distribution and evaluation. We conducted comparative analyses of handoff adherence and survey questions as well as a thematic analysis of provider-free responses. We evaluated 146 electronic handoffs orthopaedic residents, fellows, and advanced practice providers 3.5 years after OrthoPass implementation. Compared with 18-month levels, adherence was sustained across five of nine handoff domains and was markedly improved in two domains. Furthermore, provider valuations of OrthoPass improved regarding promoting communication and patient safety (83% versus 70%) and avoiding patient errors and near misses (72% versus 60%). These improvements were further substantiated by positive trends in Agency for Healthcare Research and Quality Surveys on Patient Safety Culture hospital survey data. Thematic analysis of free responses shared by 37 providers (42%) generated favorable, unfavorable, and balanced themes further contextualized by subthemes. At 3.5 years after its introduction, OrthoPass continues to improve patient handoff quality and to support provider notions of patient safety. Although providers acknowledged the benefits of this electronic handoff tool, they also shared unique insights into several drawbacks. This feedback will inform ongoing efforts to improve OrthoPass
The effectiveness of the controlled release of gentamicin from polyelectrolyte multilayers in the treatment of Staphylococcus aureus infection in a rabbit bone model
While the infection rate of orthopedic implants is low, the required treatment, which can involve six weeks of antibiotic therapy and two additional surgical operations, is life threatening and expensive, and thus motivates the development of a one-stage re-implantation procedure. Polyelectrolyte multilayers incorporating gentamicin were fabricated using the layer-by-layer deposition process for use as a device coating to address an existing bone infection in a direct implant exchange operation. The films eluted about 70% of their payload in vitro during the first three days and subsequently continued to release drug for more than four additional weeks, reaching a total average release of over 550 μg/cm[superscript 2]. The coatings were demonstrated to be bactericidal against Staphylococcus aureus, and degradation products were generally nontoxic towards MC3T3-E1 murine preosteoblasts. Film-coated titanium implants were compared to uncoated implants in an in vivo S. aureus bone infection model. After a direct exchange procedure, the antimicrobial-coated devices yielded bone homogenates with a significantly lower degree of infection than uncoated devices at both day four (p < 0.004) and day seven (p < 0.03). This study has demonstrated that a self-assembled ultrathin film coating is capable of effectively treating an experimental bone infection in vivo and lays the foundation for development of a multi-therapeutic film for optimized, synergistic treatment of pain, infection, and osteomyelitis.National Institutes of Health (U.S.) (National Institute on Aging Grant 5R01AG029601-03
Results of a Feasibility Randomized Controlled Trial (RCT) of the Toolkit for Optimal Recovery (TOR): A Live Video Program to Prevent Chronic Pain in At-Risk Adults with Orthopedic Injuries
Background: Orthopedic injuries are the leading cause of hospital admissions in the USA, and many of these patients transition into chronic pain. Currently, there are no evidence-based interventions targeting prevention of chronic pain in patients with orthopedic injuries. We iteratively developed a four-session intervention “The Toolkit for Optimal Recovery” (TOR) which we plan to subsequently test for efficacy in a phase III hybrid efficacy-effectiveness multi-site clinical trial. In order to prevent methodological weaknesses in the subsequent trial, we conducted a feasibility pilot to evaluate the TOR delivered via secure live video versus usual care (UC) in patients with orthopedic injuries from an urban, level I trauma clinic, who screen in as at risk for chronic pain and disability. We tested the feasibility of recruitment, acceptability of screening, and randomization methods; acceptability of the intervention, treatment adherence, and treatment fidelity; satisfaction with the intervention; feasibility of the assessment process at all time points; acceptability of outcome measures for the definitive trial; and within-treatment effect sizes.
Methods: We aimed to recruit 50–60 participants, randomize, and retain them for ~ 4 months. Assessments were done electronically via REDCap at baseline, post-intervention (approximately 5 weeks after baseline), and 3 months later. We followed procedures we intend to implement in the full-scale hybrid efficacy-effectiveness trial.
Results: We recruited 54 participants and found that randomization and data collection procedures were generally acceptable. The majority of participants were white, educated, and employed. Warm hand-off referrals were more effective than research assistants directly approaching patients for participation without their providers’ engagement. Feasibility of recruitment, acceptability of screening, and randomization were good. Satisfaction with the program, adherence to treatment sessions, and treatment fidelity were all high. There were no technical issues associated with the live video delivery of the TOR. There was minimal missing data and outcome measures were deemed appropriate. Effect sizes for improvement after participation in TOR were moderate to large. There were many lessons learned for future trials.
Conclusions: This study provided evidence of the feasibility of the planned hybrid efficacy-effectiveness trial design when implemented at our home institution. Establishing feasibility of the intervention and study procedures at other trauma centers with more diverse patient populations and different clinical practices is required before a multi-site phase III efficacy-effectiveness trial.
Trial registration: ClinicalTrials.gov ID: NCT03405610. Registered on January 28, 2018—retrospectively registered
Understanding Barriers and Facilitators to Implementation of Psychosocial Care within Orthopedic Trauma Centers: A Qualitative Study with Multidisciplinary Stakeholders from Geographically Diverse Settings
BACKGROUND: Psychosocial factors are pivotal in recovery after acute orthopedic traumatic injuries. Addressing psychosocial factors is an important opportunity for preventing persistent pain and disability. We aim to identify barriers and facilitators to the implementation of psychosocial care within outpatient orthopedic trauma settings using the Consolidated Framework for Implementation Research (CFIR) and Proctor\u27s taxonomy of implementation outcomes, and to provide implementation strategies derived from qualitative data and supplemented by the Expert Recommendations for Implementing Change.
METHODS: We conducted live video qualitative focus groups, exit interviews and individual interviews with stakeholders within 3 geographically diverse level 1 trauma settings (N = 79; 20 attendings, 28 residents, 10 nurses, 13 medical assistants, 5 physical therapists/social workers, and 3 fellows) at 3 trauma centers in Texas, Kentucky, and Massachusetts. We used directed and conventional content analyses to derive information on barriers, facilitators, and implementation strategies within 26 CFIR constructs nested within 3 relevant Proctor outcomes of acceptability, appropriateness, and feasibility.
RESULTS: Stakeholders noted that implementing psychosocial care within their practice can be acceptable, appropriate, and feasible. Many perceived integrated psychosocial care as crucial for preventing persistent pain and reducing provider burden, noting they lack the time and specialized training to address patients\u27 psychosocial needs. Providers suggested strategies for integrating psychosocial care within orthopedic settings, including obtaining buy-in from leadership, providing concise and data-driven education to providers, bypassing stigma, and flexibly adapting to fast-paced clinics.
CONCLUSIONS: Results provide a blueprint for successful implementation of psychosocial care in orthopedic trauma settings, with important implications for prevention of persistent pain and disability
Docosahexaenoic acid lowers cardiac mitochondrial enzyme activity by replacing linoleic acid in the phospholipidome
Cardiac mitochondrial phospholipid acyl chains regulate respiratory enzymatic activity. In several diseases, the rodent cardiac phospholipidome is extensively rearranged; however, whether specific acyl chains impair respiratory enzyme function is unknown. One unique remodeling event in the myocardium of obese and diabetic rodents is an increase in docosahexaenoic acid (DHA) levels. Here, we first confirmed that cardiac DHA levels are elevated in diabetic humans relative to controls. We then used dietary supplementation of a Western diet with DHA as a tool to promote cardiac acyl chain remodeling and to study its influence on respiratory enzyme function. DHA extensively remodeled the acyl chains of cardiolipin (CL), mono-lyso CL, phosphatidylcholine, and phosphatidylethanolamine. Moreover, DHA lowered enzyme activities of respiratory complexes I, IV, V, and I+III. Mechanistically, the reduction in enzymatic activities were not driven by a dramatic reduction in the abundance of supercomplexes. Instead, replacement of tetralinoleoyl-CL with tetradocosahexaenoyl-CL in biomimetic membranes prevented formation of phospholipid domains that regulate enzyme activity. Tetradocosahexaenoyl-CL inhibited domain organization due to favorable Gibbs free energy of phospholipid mixing. Furthermore, in vitro substitution of tetralinoleoyl-CL with tetradocosahexaenoyl-CL blocked complex-IV binding. Finally, reintroduction of linoleic acid, via fusion of phospholipid vesicles to mitochondria isolated from DHA-fed mice, rescued the major losses in the mitochondrial phospholipidome and complexes I, IV, and V activities. Altogether, our results show that replacing linoleic acid with DHA lowers select cardiac enzyme activities by potentially targeting domain organization and phospholipid-protein binding, which has implications for the ongoing debate about polyunsaturated fatty acids and cardiac health
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