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Cellular senescence has emerged as a significant and potentially tractable mechanism of aging and multiple aging‐related conditions. Biomarkers of senescent cell burden, including molecular signals in circulating immune cells and the abundance of circulating senescence‐related proteins, have been associated with chronological age and clinical parameters of biological age in humans. The extent to which senescence biomarkers are affected by interventions that enhance health and function has not yet been examined. Here, we report that a 12‐week structured exercise program drives significant improvements in several performance‐based and self‐reported measures of physical function in older adults. Impressively, the expression of key markers of the senescence program, including p16,p21, cGAS, and TNFα, were significantly lowered in CD3+ T cells in response to the intervention, as were the circulating concentrations of multiple senescence‐related proteins. Moreover, partial least squares discriminant analysis showed levels of senescence‐related proteins at baseline were predictive of changes in physical function in response to the exercise intervention. Our study provides first‐in‐human evidence that biomarkers of senescent cell burden are significantly lowered by a structured exercise program and predictive of the adaptive response to exercise. [ABSTRACT FROM AUTHOR]

Background: Frailty confers risk for surgical morbidity and mortality. Whether patient-reported measures of health, well-being, or quality of life respond differently to surgery in non-frail and frail individuals is unknown.Methods: Older adults with severe aortic stenosis presenting for surgery were assessed for frailty using Cardiovascular Health Study Criteria. Patient-reported measures of functional capacity (Duke Activity Status Index [DASI]), physical and mental health (Medical Outcomes Study Short Form-Physical and Mental Component Scales [SF-12 PCS and SF-12 MCS, respectively]), well-being (linear analogue self-assessment [LASA]), and quality of life (LASA) were administered before and 3 months after surgery.Results: Of 103 participants (mean age of 80.6 years), 54 were frail. Frail participants had lower baseline DASI, SF-12 PCS, SF-12 MCS, physical well-being, and quality of life scores than non-frail participants. At follow-up, frail participants showed significant improvement in physical function, with DASI and SF-12 PCS scores improving by 50% and 14%, respectively. Non-frail subjects did not significantly improve in these measures. SF-12 MCS scores also improved to a greater extent in frail compared to non-frail participants (3.6 vs < 1 point). Furthermore, the frail participants improved to a greater extent than non-frail participants in physical well-being (21.6 vs 7.1 points) and quality of life measures (25.1 vs 8.7 points).Conclusions: Frailty is prevalent in older adults with severe aortic stenosis and is associated with poor physical and mental function, physical well-being, and quality of life. In response to surgery, frail participants exhibited greater improvement in these patient-centered outcomes than non-frail peers. [ABSTRACT FROM AUTHOR]

Background Performance-based measures of physical function predict morbidity following non-transplant surgery. Study objectives were to determine whether physical function predicts outcomes after kidney transplant and assess how physical function changes post-transplant. Methods We conducted a prospective study involving living donor kidney transplants recipients at our center from May 2012 to February 2014. Physical function was measured using the Short Physical Performance Battery (SPPB [balance, chair stands, gait speed]) and grip strength testing. Initial length of stay (LOS), 30- day rehospitalizations, allograft function, and quality of life (QOL) were assessed. Results The majority of the 140 patients in our cohort had excellent pre-transplant physical function. In general, balance scores were more predictive of post-transplant outcomes than the SPPB. Decreased pre-transplant balance was independently associated with longer LOS and increased rehospitalizations but not with post-transplant QOL; 35% of patients experienced a clinically meaningful (≥ 1.0 m/s) improvement in gait speed 4 months post-transplant. Conclusions Decreased physical function may be associated with longer LOS and rehospitalizations following kidney transplant. Further studies are needed to confirm this association. The lack of relationship between pre-transplant gait speed and outcomes in our cohort may represent a ceiling effect. More comprehensive measures, including balance testing, may be required for risk stratification. [ABSTRACT FROM AUTHOR]

Purpose: We devised a testing apparatus for in vivo analysis of ankle stability. The purpose of the study was to test the reliability of this apparatus and to determine the stability pattern of the ankle-hindfoot complex in healthy, asymptomatic volunteers and in patients with ankle instability.Methods: Ten healthy individuals were studied, and testing was repeated on the same day and different days. Three patients with symptomatic, unstable ankles were also tested on both involved and uninvolved sides. Constant inversion torque was applied, then internal rotation torque, while moving the ankle throughout the range of sagittal motion. Three-dimensional kinematics of the ankle-hindfoot complex were measured by an electromagnetic tracking system.Results: Measurements were repeatable, with intraclass correlation coefficients 0.9 or better. Variability was observed among controls, but motion curve patterns were consistent. Motion curve slopes were sensitive in differentiating between unstable and stable ankles.Conclusions: Most previous reports are in vitro studies conducted with the ankle in one position, manual stress applied, or joint positions estimated with planar radiographs. Our study indicated that more accurate diagnosis of severity of ankle ligament injuries may be possible. [ABSTRACT FROM AUTHOR]

This study examined the effect of seat position on handrim biomechanics. Thirteen experienced users propelled a wheelchair over a smooth level floor at a self-selected speed. Kinetic and temporal-distance data were collected with the use of an instrumented rim and a motion analysis system. A custom-designed axle was used to change the seat position. We used repeated measures analysis of variance to evaluate if differences existed in the temporal-distance and kinetic data with change in seat position. Results showed that a shorter distance between the axle and shoulder (low seat height) improved the push time and push angle temporal variables (p < 0.0001). Tangential force output did not change with seat position. Axial and radial forces were highest in the lowest seat position (p < 0.001). Propulsion efficiency as measured by the fraction of effective force did not significantly change with seat position. [ABSTRACT FROM AUTHOR]

Scapular position has been hypothesized to influence rotator cuff function, but no current methods exist to reliably measure shoulder rotation strength in different scapular positions. The purpose of this study was to develop a reliable technique to measure isokinetic (ISOK) and isometric (ISOM) shoulder rotation strength with the scapula protracted. Ten healthy volunteers (5 male, 5 female, ages 20--41) completed two to three ISOM and five ISOK (90 degrees/second) internal rotation (IR) and external rotation (ER) repetitions in a position of scapular protraction with the shoulder abducted 45 degrees in the scapular plane. Subjects returned 24--72 hours later to repeat testing. All torque measurements in the protracted position exhibited excellent intersession reliability (ICCs > 0.97). Shoulder rotational torque can be measured in the protracted scapula position with excellent reliability using the new technique described. Establishing the reliability of the protracted technique is a necessary prerequisite for the completion of future studies examining quantitative differences in rotational torque generation between the neutral and protracted scapula positions in the functional shoulder position of 45 degrees of scapular plane abduction. [ABSTRACT FROM AUTHOR]

Rotationplasty is a surgical procedure designed to achieve a durable reconstruction after the resection of tumors about the knee. However, because of the recent advances with expandable prostheses, rotationplasty has been less popular in the skeletally immature patient, particularly in the United States. We assessed the functional outcome of patients who had rotationplasty to allow better comparison with other operative techniques in this patient population. Seven patients, who were operated on at our institution at an average age of 9.4 years (range, 5-14 years), had a followup of at least 4 years and were evaluated in the Motion Analysis Laboratory. The gait analysis included kinetic, kinematic and temporal-distance parameters to evaluate the patient's functional performance. The data also were compared with measurements of a population of 25 able-bodied subjects and with four subjects with distal above-knee amputation. All patients had the ability to weightbear fully. All patients ambulated without assistive devices. Gait analysis of patients with rotationplasty revealed only slight asymmetry regarding stride duration, stride length, cadence, velocity and stance-swing ratio compared with healthy subjects. Although the gait was similar to subjects with distal above-knee amputation, knee motion was superior in patients who had rotationplasty. Rotationplasty offers a durable reconstruction. Rotationplasty allows the patient to actively control the knee, which results in a coordinated gait pattern, which is similar to the gait of the able-bodied population, and better than in subjects with distal-knee amputation.

Objectives: To study maximal upper-extremity torque values and agonist/antagonist torque ratios in a sample of individuals with paraplegia and to compare these values with a sample of age-, gender-, and weight-matched able-bodied individuals., Design: Cross-sectional, case-control study., Setting: A biomechanics laboratory., Participants: A convenience sample of 15 men with complete (American Spinal Injury Association class A) T5-L2 paraplegia and 15 able-bodied control subjects., Interventions: Not applicable., Main Outcome Measures: Maximal isometric torques of 12 upper-extremity muscle groups (shoulder, elbow, and wrist flexion and extension; shoulder abduction and adduction; shoulder internal and external rotation; elbow pronation and supination) were measured with custom dynamometers., Results: Maximal torque values and agonist/antagonist torque ratios for the shoulder, elbow, and wrist functions did not differ between the control subjects and those with complete paraplegia, with the exception of the supination/pronation torque ratio, which was significantly higher in the able-bodied control group., Conclusion: Wheelchair propulsion and other functional activities, such as transfers, do not significantly affect maximum torque production of the upper extremities in individuals with paraplegia. On the basis of these findings, arguments that upper-extremity muscle imbalances are important contributory factors to upper-extremity pain and dysfunction in this group may be too simplistic., (Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)

Objectives: To examine the effect of scapular protraction (SP) and scapular retraction (SR) on isometric shoulder elevation strength measured in the sagittal plane and to test the hypothesis that strength would be significantly reduced when tested in the SP position relative to the neutral resting scapular position (SN)., Design: Prospective before-after trial., Setting: Multidisciplinary sports medicine center., Participants: Ten healthy volunteers (5 men, 5 women) ages 26 to 43 years recruited from the Mayo Clinic, Rochester, MN., Interventions: Subjects completed 3 maximal isometric shoulder elevation contractions at 90 degrees of sagittal plane elevation in the SN, SP, and SR positions. The order of scapular positions was varied to minimize fatigue effects. Mean isometric strength values were compared by using Student t tests., Main Outcome Measures: Isometric shoulder elevation strength for the 3 scapular positions., Results: Isometric strength was significantly lower for the SP position compared with the SN position (8.5 +/- 3.4 kg vs 11.1 +/- 4.0 kg, P <.0005) and for the SR position relative to the SN position (7.8 +/- 3.3 kg vs 11.1 +/- 4.0 kg, P <.00003). Strength values did not differ between the SP and SR positions (P =.38)., Conclusions: Movement of the scapula into a protracted or retracted position results in a statistically significant reduction in isometric shoulder elevation strength as measured in this study. Further research is warranted to examine the relationship between scapular position and shoulder muscle function., (Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)