Biomedical subjects

Deborah L Burr

Publications and source records attributed to Deborah L Burr.

4 recordsLinked to original sources

PubMed2005

Differences among outcome measures in occupational low back pain.

The rate of recurrence in low back pain patients has been reported as high as 70%; therefore, it is believed that researchers have a poor understanding of low back pain recovery. To enhance our understanding of recovery, a large cross-sectional study was conducted to compare outcome measures of return to work, impairment of activities of daily living, pain symptoms, and functional performance probability. A total of 208 workers were examined. The percentage of workers recovered based on return to work criteria was 99% compared to 25% for impairment of activities of daily living, 17% for symptoms, and 12.5% for functional performance probability. Single functional performance measures of range of motion, velocity, and acceleration had recovery rates of 59, 13, and 10%, respectively. It appears that all these criteria are measuring very different parameters of low back pain recovery. The residual loss in functional performance may indicate a decreased tolerance to physical demand providing potential insight for why recurrent low back pain rates are high.

Activities of Daily Living↗

PubMed2004

The influence of individual low back health status on workplace trunk kinematics and risk of low back disorder.

A case-control study was conducted to determine whether or not kinematic-based low back disorder risk measurement (Marras et al. 1993) of the job was significantly different for those workers suffering from recent low back injuries compared to asymptomatic controls. Two hundred low back injured workers returning to full duty work and 200 asymptomatic controls were evaluated while performing the same job. There were no statistically significant differences between the two groups on any trunk motion measures or workplace measures. Therefore, job design is dictating the kinematic motions of the torso and not the worker's low back health. In addition, there was not a significant difference in job risk estimates using the lumbar motion monitor risk model. The mean risk (and standard deviation) for the low back injured group and the asymptomatic controls was 0.502 (0.178) and 0.501 (0.193), respectively. This study suggests that trunk kinematics and subsequent risk estimates are dictated primarily by job design and not influenced by the low back health status of the worker.

Adult↗

PubMed2004

Differences in motor recruitment and resulting kinematics between low back pain patients and asymptomatic participants during lifting exertions.

BACKGROUND: Low back disorders are a prevalent problem in society today and may lead to chronic debilitating low back pain. Developing our understanding of temporal muscle and kinematic patterns during manual material handling tasks may provide insight for preventing the cascading series of events leading to chronic low back pain. METHODS: Sixty-two low back pain patients and 61 asymptomatic participants performed a variety of lifting exertions that varied in lift origin horizontal and vertical distance, lift asymmetry, and weight. Electromyographic activity of 10 trunk muscles as well as trunk and pelvic kinematics was recorded during each exertion. Differences in muscle activation and kinematic parameters were compared between low back pain patients and asymptomatic participants as a function of experimental conditions. FINDINGS: Both the left and right erector spinae activated significantly earlier and were on significantly longer in low back pain patients compared to asymptomatic participants. The horizontal and vertical location of the lift influenced the EMG and kinematic differences between the low back pain patients and asymptomatic participants. INTERPRETATION: These finding indicate that low back pain patients would be exposed to increase muscle activity resulting in higher spine loads for a greater length of time compared to asymptomatic participants. The longer exposure time to increased spine load may lead to greater risk of future low back injury and cascading events leading to debilitating low back pain. The longer muscle activation time suggests that low back pain patients have changed their motor program from an open to a closed loop system.

Adult↗

PubMedDate not supplied

Changes in spine loading patterns throughout the workday as a function of experience, lift frequency, and personality.

BACKGROUND CONTEXT: Psychosocial stressors have been associated with low back pain reporting. However, response to psychosocial risk factors may be dependent on the individual's personality type that, in turn, can affect muscle recruitment and spine loading. This study explores how personality might be associated with spine loading during repetitive lifting performed throughout an entire work shift. PURPOSE: Assess spine loading as a function of an individual's personality type during repetitive, long-term exposure to a materials handling tasks. STUDY DESIGN: Laboratory experiment where experienced and inexperienced participants performed repetitive, asymmetric lifts at various load and lift frequency levels throughout a series of 8-hour exposure periods. Spine loads were monitored throughout the work period. PATIENT SAMPLE: Twelve novice and 12 experienced materials handlers who were asymptomatic for back pain. OUTCOME MEASURES: Spine compression, anterior-posterior (A/P) shear, and lateral shear at the L5-S1 level. METHODS: Participants were categorized into personality types based upon the Myers-Briggs personality type indicator. An electromyography-assisted biomechanical model was used to assess spine compression, A/P shear, and lateral shear throughout the exposure period. RESULTS: The results indicate that intuitors had higher shear spinal loading regardless of moment exposure, lift frequency, and time through the work period, compared with the sensor personality type. In addition, higher spine compressive and shear forces occurred in the perceiver personality compared with the judgers' personality trait, regardless of moment and, often, lift frequency. Novice lifters typically experienced greater spine loading. CONCLUSIONS: The results suggest that when there exists a personality-job environment mismatch, spinal loading increases via an increase in antagonistic co-contraction. The trends suggest that inherent personality characteristics may play a role in one's motor control strategies when performing a repetitive lifting task.

Adult↗