Elizabeth A. Tully

Video analysis of sagittal spinal posture in healthy young and older adults.

OBJECTIVE Changes in posture are of concern because of their association with pain or impaired physical function. Previous studies that have used computer-aided video motion analysis systems to measure posture have been compromised by the use of problematic models of skin marker placement. This study aimed to quantify and compare sagittal spinal posture in standing and sitting between young and older adults using a two-dimensional PEAK Motus system and a revised skin marker model. METHODS Twenty-four healthy young adults and 22 healthy older adults volunteered for this study. The angles of the upper and lower cervical spine, thoracic spine, lumbar spine as well as the orientations of the head, neck, and pelvic plane with respect to an external reference were measured in the standing and sitting positions. RESULTS Compared to young adults, healthy older adults demonstrated a forward head posture, with increased lower cervical spine flexion and increased upper cervical extension in both positions. Older adults also sat with significantly increased thoracic kyphosis and decreased lumbar spine flexion. CONCLUSION The angular relationship between adjacent spinal regions in the sagittal plane can be objectively quantified using image-based analysis. The concept that the anteroposterior tilt of the pelvis in standing dictates the lumbar and thoracic curves was supported by the correlations between these adjacent regions in both age groups. The model of skin marker placement used in this study can have a broader application as a clinical tool for image-based postural assessment.

A Targeted Home- and Center-Based Exercise Program for People After Total Hip Replacement: A Randomized Clinical Trial

OBJECTIVE To examine the physical function, gait, and quality of life of patients after total hip replacement (THR) randomly assigned to either a targeted home- or center-based exercise program. DESIGN Randomized controlled trial. SETTING Rehabilitation research center in Australia. PARTICIPANTS Twenty-three patients with unilateral THR were randomly assigned to a supervised center-based exercise group (n=11) or an unsupervised home-based exercise group (n=12). INTERVENTION The center-based group completed an 8-week targeted exercise program while under the direct supervision of a physiotherapist. After initial instruction, the home-based group completed the 8-week targeted exercise program at home without further supervision. MAIN OUTCOME MEASURES Quality of life, physical function, and spatiotemporal measures of gait. RESULTS No significant interaction (group by time) or main effects of grouping were found. Within each group, quality of life, and stair climbing improved significantly (P<.05) as did Timed Up & Go test and 6-minute walk test performances (P<.05). Walking speed increased by 16 cm/s (P<.01), cadence by 8 steps/min (P<.05), step length by 4.7 cm (P<.05), and double-support time reduced by a factor of 16%. Step length symmetry showed significant improvement (P<.05) over time. Step length differential between the affected and unaffected limbs reduced from 4.0 to 2.7 cm. CONCLUSIONS The targeted strengthening program was effective for both the home- and center-based groups. No group differences were found in the majority of the outcome measures. This finding is important because it shows that THR patients can achieve significant improvements through a targeted strengthening program delivered at a center or at home.

Computer-aided video analysis of vertebrofemoral motion during toe touching in healthy subjects

OBJECTIVE Despite widespread use of the toe touch test, the relative contribution from vertebral and hip movements has not been clearly established, largely because of unsatisfactory measurement techniques. This study aimed to reinvestigate the kinematics of toe touching by combining computerized videotape analysis with a new model of reference marker placement. METHOD Twenty-two subjects were videotaped during active toe touching from upright standing. Computer software was then used to derive the sagittal thoracic, lumbar, and hip angles at .02-sec intervals throughout the movement. RESULTS Hip flexion was directly proportional to toe touch distance (TTD) (r2 = .71) but not lumbar flexion (r2 = .17) or thoracic (r2 = .20) excursion. On average there was .8 degree of thoracolumbar flexion for every 1 degree of hip flexion; however, there were wide variations between subjects. In 19 of 22 subjects the thoracic spine flexed and extended relatively equal amounts during the test resulting in a small total thoracic excursion of 4.8 degrees flexion in unsuccessful toe touchers and 4.0 degrees extension in successful toe touchers. CONCLUSION The separate contributions of hip, lumbar, and thoracic mobility to toe touching or any other vertebrofemoral motion can only be accurately determined by a measurement strategy that uses the plane of the pelvis to separate vertebral from hip motion and uses tangents at the limits of the thoracic and lumbar regions to separate lumbar from thoracic motion. Using this model the authors found that TTD is not a reliable indicator of either vertebral or hip mobility.

Radiographic measures of thoracic kyphosis in osteoporosis: Cobb and vertebral centroid angles

ObjectiveSeveral measures can quantify thoracic kyphosis from radiographs, yet their suitability for people with osteoporosis remains uncertain. The aim of this study was to examine the validity and reliability of the vertebral centroid and Cobb angles in people with osteoporosis.Design and patientsLateral radiographs of the thoracic spine were captured in 31 elderly women with osteoporosis. Thoracic kyphosis was measured globally (T1–T12) and regionally (T4–T9) using Cobb and vertebral centroid angles. Multisegmental curvature was also measured by fitting polynomial functions to the thoracic curvature profile. Canonical and Pearson correlations were used to examine correspondence; agreement between measures was examined with linear regression.ResultsModerate to high intra- and inter-rater reliability was achieved (SEM = 0.9–4.0°). Concurrent validity of the simple measures was established against multisegmental curvature (r = 0.88–0.98). Strong association was observed between the Cobb and centroid angles globally (r = 0.84) and regionally (r = 0.83). Correspondence between measures was moderate for the Cobb method r = 0.72), yet stronger for the centroid method (r = 0.80). The Cobb angle was 20% greater for regional measures due to the influence of endplate tilt.ConclusionsRegional Cobb and centroid angles are valid and reliable measures of thoracic kyphosis in people with osteoporosis. However, the Cobb angle is biased by endplate tilt, suggesting that the centroid angle is more appropriate for this population.

Does the toe-touch test predict hamstring injury in Australian Rules footballers?

This prospective cohort study evaluated the relationship of hamstring and lumbar spine flexibility to hamstring injury. Sixty-seven senior male Australian Rules footballers were videotaped while performing a toe-touch test from erect standing. The Peak Motion Measurement System was used to obtain measurements of end range hip flexion, lumbar flexion, toe-touch distance (TTD) and the ratio of lumbar spine flexion to hip flexion. Over the following football season, eight subjects (11.9 per cent) sustained a hamstring strain. Results showed no significant difference between the hamstring injured or uninjured players for any of the measured variables with no variable able to predict the likelihood of injury (p > 0.05). In this cohort, the toe-touch test would not appear to be a useful screening tool to identify footballers at risk for hamstring strain.

Sagittal spinal posture after Pilates-based exercise in healthy older adults.

Study Design. Longitudinal, repeated-measures study. Objective. The aim of this study was to determine changes in sagittal spinal posture in older adults during standing and sitting after a Pilates-based exercise program. Summary of Background Data. Pilates exercise is purported to improve posture, however, few peer-reviewed articles are available to provide scientific support. Most previous studies were conducted in young dancers, and the effect of Pilates exercise on spinal posture in older adults remained unclear. Methods. Thirty-four healthy older adults aged over 60 years volunteered for this study. A two-dimensional PEAK Motus motion analysis system was used to measure sagittal spinal angles. Participants were tested on 2 occasions before the exercise program to establish a baseline measure, and undertook a supervised Pilates-based exercise program twice weekly for 10 weeks. Participants were tested on another 2 occasions, immediately after the exercise program, and after a short-term follow-up. Results. Baseline measures in both standing and sitting postures remained unchanged except for the lumbar spine angle in sitting. Immediately after the Pilates-based exercise program, older adults stood with slightly decreased thoracic flexion and sat with slightly increased lumbar extension. No significant differences were found during the follow-up period. Conclusion. The individually designed Pilates-based exercise program was feasible for healthy older adults, and the high attendance rate supports the suitability of the exercise program over a long period. Considering the variability of the baseline measure, small improvement was only observed in the thoracic kyphosis during standing. The long-term effect of Pilates exercise requires further investigation.

Kinematics of Rising From a Chair: Image-Based Analysis of the Sagittal Hip-Spine Movement Pattern in Elderly People Who Are Healthy

Background Rehabilitation of elderly patients with sit-to-stand (STS) dysfunction includes retraining coordinated movement among participating body segments. Although trunk position is considered important, spinal movement has not been measured. Objective The aim of this study was to describe the sagittal thoracolumbar kinematics and hip-lumbar interaction during the STS task in elderly people who were healthy in order to guide physical therapists in developing treatment strategies. Design This was an observational study. Methods Ten retroreflective markers were attached to the midline thoracolumbar spine, pelvis, and right lower limb of 41 elderly people who were healthy. A 2-dimensional video analysis system was used to measure sagittal thoracic, lumbar, hip, and knee joint angles during the STS task. Maximal available flexion-extension angles in these joints and regions also were determined. Results Prior to buttocks lift-off, forward trunk lean comprised concurrent hip and lumbar flexion and thoracic extension. Hip flexion dominated, with a hip/lumbar ratio of 4.7:1 and a thoracic/lumbar ratio of 1.7:1. The hip and lumbar spine contributed 90% and 23% of their maximal available flexion angle, respectively, and the thoracic spine contributed 86% of its maximal extension range of movement. After lift-off, the hips and lumbar spine extended (ratio of 5.2:1), and the thoracic spine flexed (thoracic/lumbar ratio of 0.4:1). At lift-off, the hips and knees were similarly flexed (96°) and then locked together in a linear pattern of extension. Following lift-off, there was a brief transition phase (5% of STS duration) in which, although the hips, knees, and lumbar spine were extending, the trunk continued to flex forward a few degrees. Limitations Results may differ in elderly people who are less active. Conclusions The revised model for image-based analysis demonstrated concurrent hip and thoracolumbar movement during the STS task. Close to full available hip flexion and thoracic extension were needed for optimal STS performance.

Video based measurement of sagittal range of spinal motion in young and older adults

A revised model of skin marker placement with the two-dimensional (2D) PEAK Motus system was used to investigate the effect of aging on sagittal range of spinal motion. Twenty-four healthy young adults and twenty-two healthy older adults were videotaped while performing the movements of flexion and extension in each spinal region--cervical, thoracic and lumbar spine. Alternative movement tests that may allow a greater range of motion (ROM) for thoracic extension and lumbar flexion were also investigated. Older adults demonstrated significantly decreased flexion/extension ranges in the cervical, thoracic and lumbar spine. The movement of cat-stretch in the all-fours position allowed greater thoracic extension, and the movement of toe-touch in standing permitted greater lumbar flexion. This study provides reference data for sagittal ranges of spinal motion in healthy young and older adults as measured by a 2D imaged-based system. The sagittal model of skin marker placement used in this study can have a broader application for ROM measurement in the clinical setting using a digital camera and freely downloadable software.

Kinematics of sagittal spine and lower limb movement in healthy older adults during sit-to-stand from two seat heights

Study Design. A cross-sectional study to examine the sagittal kinematics of spine and lower limb movement during sit-to-stand (STS). Objective. To describe the sagittal kinematics of the spine and lower limb in healthy older adults during STS from 2 seat heights. Summary of Background Data. Older adults with age-related changes in the neuromusculoskeletal system are likely to have difficulty in STS. However, little is known about movement of the spinal regions and their interaction with the lower limb during STS, and the effect of seat height. Methods. Thirty-two healthy older adults aged over 60 years were videotaped performing STS from 2 seat heights. A 2-dimensional video motion analysis system with a revised sagittal model was used to measure angular displacement and velocity for the cervical, thoracic, lumbar spine, and the lower limb joints. Results. Concurrent flexion in the hip joint and lumbar spine was accompanied by extension in the thoracic, lower, and upper cervical spine as the trunk leaned forward. After the buttocks lifted off (LO) the chair, the movement interaction in the spine and hip joint was reversed. Some significant age-related changes during STS included downward head tilt at LO, decreased lumbar range of motion, and a large between-participant variation in the movement ratios. Statistically significant differences in the temporal parameters, angular displacement, and velocity were also found when standing from a lower chair. Conclusion. This study provides a detailed description of STS in healthy older adults, which has implications for rehabilitation of elderly patients who have difficulty with this activity. Clinicians need to be aware of the concurrent contribution of the hip joint and lumbar spine to trunk forward lean, the importance of thoracic extension during the pre-LO phase and the downward gaze at LO in healthy older adults.

Knee Joint Mobility and Position Sense in Healthy Young Adults

Summary Background and purpose It has been suggested that hypermobile joints may have disturbed proprioception which could compound their mechanical predisposition to injury and degeneration. Accordingly, this study investigated position sense in young adults with increased knee mobility. Methods After determining the passive limit of extension in the non-dominant knee of 44 healthy adults (35 women, 9 men, aged 18 to 29 years), five active position sense tests, each followed by an ipsilateral limb matching response, were administered within an average 13.4° of the passive extension limit. Following computer analysis of videotape images of the test and response positions, position sense accuracy was calculated as the average of the five test-response mismatches, and reliability as the standard deviation from this average. Results Although knee extension mobility and position sense were poorly correlated, analysis of variance revealed greater accuracy (1.5° versus 2.4°, p versus 2.2°, p Conclusions Actively tested, position sense accuracy and reliability were normal in young adults with asymptomatic increased knee mobility. Further studies are required to clarify the status of active position sense in subjects with symptomatic hypermobility.