This is a retrospective pilot study of 14 individuals (8 men, 6 women) with unilateral spastic cerebral palsy (USCP), aged 3 to 28 years, and with a mean age = 13 ± 7.8. The inclusion criteria included USCP individuals who ambulate without an assistive device. The exclusion criteria included individuals who are nonambulatory, ambulate with a device, or are unable to follow instructions.

Impaired hip muscle function has often been cited as a contributing factor to the development of iliotibial band syndrome (ITBS), yet our full understanding of this relationship is not well established. The objective of this study was to examine the effect of fatigue on hip abductor muscle function in females with ITBS. Female runners, 20 healthy and 12 with a current diagnosis of ITBS, performed a treadmill run to fatigue. Prior-to and following the run to fatigue, gluteus medius strength and median frequency values (an indicator of fatigue resistance) were measured. Additionally, onset activation timing of the gluteus medius and tensor fascia latae was measured during overground running. Both healthy and injured runners demonstrated decreased gluteus medius strength following the run to fatigue (p = 0.01), but there was no interaction between groups (p = 0.78). EMG onset activation timing did not differ between groups for the gluteus medius (P = 0.19) and tensor fascia latae muscles (P = 0.52). Injured runners demonstrated decreased gluteus medius initial median frequency values suggestive of fatigue (P = 0.01). These findings suggest that the gluteus medius muscle of female runners with ITBS does not demonstrate gross strength impairments but does demonstrate less resistance to fatigue. Clinicians should consider implementation of a gluteus medius endurance training regimen into a runner's rehabilitation program.

rehabilitative device to improve early play and learning in atrisk infants.

ABSTRACTThree‐dimensional analysis of wrist motion is a growing focus in orthopedic research, however, our understanding of its validity (accuracy and reliability) remains limited. Nine human cadavers were tested to estimate wrist joint axes alignment in a postural static pose. The objective was to investigate a rater's ability to reliably align three skin‐ tracked wrist joint coordinate system (WJCS) definitions across baseline and reconstructive wrist states (intact, mid‐carpal arthrodesis, and proximal‐row carpectomy). Two WJCSs (legacy, anatomic) were based on palpated bony landmarks and the third (functional) was based on both landmarks and passive flexion‐extension motion. A coordinate frame based on the anatomic definition was tracked with bone pins and served as a reference. Each WJCS was tested in each wrist state and in three forearm position (45° pronation, neutral, 45° supination). The angular offset about each axis of the WJCS frames were calculated with respect to the reference in flexion‐extension, radial‐ulnar deviation, and pronation‐supination for every iteration. Reliability and root mean square deviation values were analyzed across wrist states. Our data suggest that no WJCS is uniformly more reliable than another. The functional WJCS definition was most consistent across intact and post‐operative states for pronation‐supination offset, but this was dependent on rater interpretation. It still however offers the practical benefit of requiring fewer landmarks. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1341–1347, 2015.

The purpose of this study was to develop a three-dimensional (3D) motion analysis based anatomical wrist joint coordinate system for measurement of in-vivo wrist kinematics. The convergent validity and reliability of the 3D motion analysis implementation was quantified and compared with manual and electrogoniometry techniques on 10 cadaveric specimens. Fluoroscopic measurements were used as the reference. The 3D motion analysis measurements (mean absolute difference [MAD] = 3.6°) were significantly less different (P < .005) than manual goniometry (MAD = 5.7°) but not (P = .066, power = 0.45) electrogoniometry (MAD = 5.0°) compared with fluoroscopy. The intraclass correlation coefficient (ICC[2,1]) was highest for 3D motion analysis compared with manual and electrogoniometry, suggesting better reliability for this technique. To demonstrate the utility of this new wrist joint coordinate system, normative data from 10 healthy subjects was obtained while throwing a dart.

Background: Many foot pathologies are associated with specific foot types. If foot structure and function are related, measurement of either could assist with differential diagnosis of pedal pathologies.Hypothesis: Biomechanical measures of foot structure and function are related in asymptomatic healthy individuals.Methods: Sixty-one healthy subjects' left feet were stratified into cavus (n = 12), rectus (n = 27) and planus (n = 22) foot types. Foot structure was assessed by malleolar valgus index, arch height index, and arch height flexibility. Anthropometrics (height and weight), age, and walking speed were measured. Foot function was assessed by center of pressure excursion index, peak plantar pressure, maximum force, and gait pattern parameters. Foot structure and anthropometric variables were entered into stepwise linear regression models to identify predictors of function.Results: Measures of foot structure and anthropometrics explained 10-37% of the model variance (adjusted R-2) for gait pattern parameters. When walking speed was included, the adjusted R-2 increased to 45-77% but foot structure was no longer a factor. Foot structure and anthropometrics predicted 7-47% of the model variance for plantar pressure and 16-64% for maximum force parameters. All multivariate models were significant (p < 0.05), supporting acceptance of the hypothesis.Discussion and conclusion: Foot structure and function are related in asymptomatic healthy individuals. The structural parameters employed are basic measurements that do not require ionizing radiation and could be used in a clinical setting. Further research is needed to identify additional predictive parameters (plantar soft tissue characteristics, skeletal alignment, and neuromuscular control) and to include individuals with pathology. (C) 2012 Published by Elsevier B.V.

Plantar pressure measurement is common practice in many research and clinical protocols. While the accuracy of some plantar pressure measuring devices and methods for ensuring consistency in data collection on plantar pressure measuring devices have been reported, the reliability of different devices when testing the same individuals is not known. This study calculated intra-mat, intra-manufacturer, and inter-manufacturer reliability of plantar pressure parameters as well as the number of plantar pressure trials needed to reach a stable estimate of the mean for an individual. Twenty-two healthy adults completed ten walking trials across each of two Novel emed-x(®) and two Tekscan MatScan(®) plantar pressure measuring devices in a single visit. Intraclass correlation (ICC) was used to describe the agreement between values measured by different devices. All intra-platform reliability correlations were greater than 0.70. All inter-emed-x(®) reliability correlations were greater than 0.70. Inter-MatScan(®) reliability correlations were greater than 0.70 in 31 and 52 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. Inter-manufacturer reliability including all four devices was greater than 0.70 for 52 and 56 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. All parameters reached a value within 90% of an unbiased estimate of the mean within five trials. Overall, reliability results are encouraging for investigators and clinicians who may have plantar pressure data sets that include data collected on different devices.

Traditional finite element (FE) analysis is computationally demanding. The computational time becomes prohibitively long when multiple loading and boundary conditions need to be considered such as in musculoskeletal movement simulations involving multiple joints and muscles. Presented in this study is an innovative approach that takes advantage of the computational efficiency of both the dynamic multibody (MB) method and neural network (NN) analysis. A NN model that captures the behavior of musculoskeletal tissue subjected to known loading situations is built, trained, and validated based on both MB and FE simulation data. It is found that nonlinear, dynamic NNs yield better predictions over their linear, static counterparts. The developed NN model is then capable of predicting stress values at regions of interest within the musculoskeletal system in only a fraction of the time required by FE simulation.

To compare wrist coupling, angular excursion, and functional performance between: healthy subjects, subject's status post midcarpal arthrodesis (MA) and proximal row carpectomy (PRC) during hammering and dart throwing.

Electromyography (EMG) of the shoulder girdle is commonly performed; however, EMG spectral properties of shoulder muscles have not been clearly defined. The purpose of this study was to determine the maximum power frequency, Nyquist rate, and minimum sampling rate for indwelling and surface EMG of the normal shoulder girdle musculature. EMG signals were recorded using indwelling electrodes for the rotator cuff muscles and surface electrodes for ten additional shoulder muscles in ten healthy volunteers. A fast Fourier transform was performed on the raw EMG signal collected during maximal isometric contractions to derive the power spectral density. The 95% power frequency was calculated during the ramp and plateau subphase of each contraction. Data were analyzed with analysis of variance (ANOVA) and paired t tests. Indwelling EMG signals had more than twice the frequency content of surface EMG signals ( p < .001). Mean 95% power frequencies ranged from 495 to 560 Hz for indwelling electrodes and from 152 to 260 Hz for surface electrodes. Significant differences in the mean 95% power frequencies existed among muscles monitored with surface electrodes ( p = .002), but not among muscles monitored with indwelling electrodes ( p = .961). No significant differences in the 95% power frequencies existed among contraction subphases for any of the muscle–electrode combinations. Maximum Nyquist rate was 893 Hz for surface electrodes and 1,764 Hz for indwelling electrodes. Our results suggest that when recording EMG of shoulder muscles, the minimum sampling frequency is 1,340 Hz for surface electrodes and 2,650 Hz for indwelling electrodes. The minimum sampling recommendations are higher than the 1,000 Hz reported in many studies involving EMG of the shoulder.

Altered gluteus medius function has been shown to affect hip and knee kinematics and loading during running, and has been linked to injury susceptibility. The majority of research has examined fresh-state function, however fatigue has significant implications on muscular function. The capacity of a muscle to resist fatigue is likely advantageous in avoiding injury. However, the effect of performing a run to exertion on gluteus medius function is unknown. Understanding these effects in a healthy population is important for future comparison with injured runners. Fatigue has been previously documented as a shift in the median frequency of the electromyographic (EMG) signal. When plotted versus time, the slope of this median frequency shift can be utilized to describe a muscle's "rate of fatigue". PURPOSE: The purpose of this study is to determine the effect of a run to exertion on the gluteus medius "rate of fatigue" in healthy female runners. METHODS: Data from nine healthy female runners (30 ±7.2 years, 1.67±.06m, 57.1±kg) were collected prior to and following a treadmill run to exertion. At both time points, EMG activity of the dominant limb gluteus medius muscle was captured during a 60-second 50% maximal voluntary isometric contraction. EMG data were initially processed in 213 ms time segments (bins) and transformed into the frequency domain using the fast Fourier transform technique. The median power frequencies were then obtained for 1.91sec intervals of data and plotted versus time. The linear slope of this curve was obtained and used to express the gluteus medius "rate of fatigue". Comparisons between pre and post-run rate of fatigue data were made using a paired samples t-test (p<0.05). RESULTS: There were no significant differences in gluteus medius rate of fatigue (P= 0.635) between the pre- and post-exertion conditions. While these results reflect data from a small sample size, they are not surprising given that the runners were healthy at the time of data collection. CONCLUSION: Healthy female runners demonstrate the ability to maintain resistance to fatigue at the gluteus medius muscle following a run to exertion. The ability of this muscle to resist fatigue may play an important role in dynamic stabilization and injury prevention for these runners.

email: HillstromH@HSS.edu, web: www.hss.edu/rehab-motion-analysis.asp INTRODUCTION The long-term goal of the kinematic wrist joint coupling project is to study complex, dynamic motions like throwing without imposing limitations on the motion. As the majority of functional tasks (vocational, recreational, and daily living activities) occur between neutral and full pronation of the forearm; one prerequisite is to establish a wrist joint coordinate system (WJCS) that is robust over a range of forearm pronation-supination positions. Our original WJCS was based upon the ISB recommended standards [1] and was reported at the past ISB meeting [2]. In this system, global wrist motion was based upon a floating axis solution between the 3 metacarpal (MC) and radius.

PURPOSE:Despite the ubiquitous use of manual goniometry in measuring objective outcomes of hand surgery and therapy, there are limited data concerning its accuracy or repeatability for wrist motion. The purpose of this study was to evaluate the accuracy and reliability (both inter- and intra-rater) in measuring wrist flexion and extension using 3 manual goniometric alignment techniques (ulnar, radial, and dorsal-volar) in cadaveric upper extremities, using fluoroscopic verification of posture as a gold standard. In addition, we sought to assess the accuracy and reliability of the dorsal-volar technique for measurement of radioulnar deviation. METHODS:External fixators were applied to 10 cadaveric wrists with intramedullary cannulated rods in the radius and third metacarpal for gold-standard fluoroscopic verification of posture. Manual goniometric measurements with each technique were captured by 2 raters (a hand surgeon and a hand therapist) for reliability measurements and by a single rater for accuracy. Wrists were positioned at angles of maximum flexion, extension, and radial and ulnar deviation for reliability testing and at preselected angles across the range of motion for accuracy testing. At each position, wrist angle was measured with a 1 degrees increment goniometer, and fluoroscopic angles were measured digitally. Intraclass correlation coefficients and root mean square values were calculated for all combinations, and analysis of variance was used to test differences between techniques. RESULTS:No technique was statistically less accurate than any other (6 degrees to 7 degrees ). Each method was found to have high intra-rater reliability. For measurement of wrist flexion and extension, the dorsal-volar technique demonstrated the greatest inter-rater reliability, as compared to ulnar and radial, respectively. CONCLUSIONS:Although each measurement technique demonstrated a similar degree of accuracy and intra-rater reliability, the dorsal-volar technique demonstrates the greatest level of inter-rater reliability for measurement of wrist flexion and extension. This information is important clinically, as measurements are regularly exchanged between hand surgeons and therapists as a basis for decisions regarding patient care.