Anne G. Hartigan

Incidence of carpal tunnel syndrome among automobile assembly workers and assessment of risk factors.

Objectives: This study defined the incidence rate of carpal tunnel syndrome (CTS) among active assembly workers and evaluated risk factors. Methods: This study followed 189 automobile assembly workers over 1 year. Incident cases were defined as workers who had no current or prior history of CTS and were subsequently diagnosed with CTS by means of active surveillance during the study. Results: The estimated annual incidence rate ranged from 1% to 10%, depending on the case definition. Significant predictors for CTS include a higher baseline median-ulnar peak latency difference, history of wrist/hand/finger tendonitis, history of diabetes, nonneutral wrist and elbow postures, and a lower self-reported social support. Conclusions: This is similar to other prospective studies that demonstrate both ergonomic and medical history are independent risk factors for development of CTS.

Risk Factors for Plantar Fasciitis Among Assembly Plant Workers

The objective of this study was to determine the relative contributions of work activity (time spent standing, walking, or sitting), floor surface characteristics, weight, body mass index, age, foot biomechanics, and other demographic and medical history factors to the prevalence of plantar fasciitis.

Predictors of Persistent Elbow Tendonitis Among Auto Assembly Workers

Introduction: Lateral and medial epicondylitis associated with work activity is a common upper extremity musculoskeletal disorder with a prevalence of 4–30% depending upon the work setting and diagnostic criteria. The influence of treatment, ergonomic factors, medical history, psychosocial variables, and aging on the improvement of symptoms has not been well defined. Methods: This was a prospective cohort study of a cohort of 45 workers with active elbow tendonitis for an average of 13 months. Complete resolution of symptoms was the defined outcome measure. Results: The predictive factors for persistent elbow tendonitis included older age (OR = 1.1, 95% CI: 0.99, 1.33), higher hand repetition level for their job(s) (OR = 2.5, 95% CI: 1.00, 6.25), more deviation from a neutral wrist position during the work activity (OR = 2.0, 95% CI: 0.80, 5.56), and lower perceived decision authority on the job (OR = 0.9, 95% CI: 0.79, 0.98). Other ergonomic, psychosocial, and electrophysiologic measures were not predictive. The models had relatively high sensitivity and specificity. Treatment effects could not be evaluated due to incomplete data available. Conclusions: Older workers with jobs requiring more repetition and awkward wrist postures, and less decision authority were less likely to have resolution of their elbow tendonitis. Implications: Workers at highest risk for persistent elbow tendonitis should be placed at jobs with lower repetition levels and that use more neutral wrist postures. Effective interventions must address both the ergonomic and psychosocial risk factors in a multifaceted approach to this problem.

Risk factors for lower extremity fatigue among assembly plant workers

BACKGROUND Work-related fatigue of the lower extremities is a known cause of lost productivity and significant employer costs. Common workplace solutions to reduce fatigue levels include anti-fatigue matting, shoe orthoses, or sit/stand work stations. However, assessment of these anti-fatigue measures within the workplace has been limited. METHODS This was a cross sectional study in an automotive assembly plant on employees with at least 6 months tenure. Subject data were collected via questionnaires including Likert-scale questions to define fatigue severity. Jobs were evaluated for lower extremity ergonomic exposures via videotaping, pedometers, interviews, and industrial engineering records. RESULTS Lower extremity fatigue at the end of the work day was associated with a higher prevalence of smoking, rheumatoid arthritis, job dissatisfaction, use of shoes with firmer outsoles, and increased time on the job spent standing or walking. Supervisor support and increased time spent on carpet were protective. Lower extremity fatigue that interfered with activities outside of work had additional risk factors including higher BMI, prior diagnosis of osteoarthritis, and increased hours per week spent working. CONCLUSIONS While these results identify carpet as being protective against lower extremity fatigue, no similar relationship was identified for anti-fatigue mats. No adverse relationship was found between hard surfaces such as concrete and lower extremity fatigue. Given the high costs associated with work-related fatigue, future areas for potential intervention include smoking cessation, specific shoe recommendations, and enhancing psychosocial aspects of work such as supervisor support.

Risk factors for foot and ankle disorders among assembly plant workers

BACKGROUND Jobs that necessitate prolonged standing and walking activities are commonly associated with workers complaints of foot and ankle pain. The objective of this study was to determine the relative contributions of work activity (time spent standing, walking, or sitting), floor surface characteristics, weight, BMI, age, foot biomechanics, and other demographic and medical history factors to the prevalence of foot and ankle disorders. METHODS A cross-sectional observational study design was used to evaluate employees of an engine manufacturing plant. The main outcome variable was foot or ankle disorders defined by pain and a positive physical examination. The independent variables included baseline demographics, medical history, ergonomic exposures, psychosocial factors, shoe characteristics and foot biomechanics. RESULTS Twenty-four percent of the cohort met the case definition of foot/ankle disorder with 10% defined as new cases. Fifty-two percent had symptoms of foot/ankle. An increased risk of presenting with foot/ankle disorders was associated with high metatarsal pressure on gait assessment, increased time spent walking, female gender, reported high job dissatisfaction, a history of rheumatoid arthritis, osteoporosis or vascular disorder. For the truck/forklift drivers, an increased number of times getting in and out of the vehicle was associated with a higher prevalence of ankle/foot problems. CONCLUSIONS An increased risk is associated with higher metatarsal pressure and increased time spent walking. These findings suggest several options for primary and secondary prevention strategies. The use of shoe orthoses with a medial longitudinal arch and metatarsal pad as well as including optional sit/stand workstations may be helpful.

Low Back Pain After Nonspinal Surgery: The Characteristics of Presumed Lumbar Paraspinal Compartment Syndrome

or persons who undergo general surgical procedures, there are a number of potential auses of early postoperative back pain. Intra-abdominal causes generally include peritoniis and kidney infection but may also include disorders related to the specific operation such s aneurysm, stone formation, etc. Intraoperative positioning, inactivity, and premorbid ack conditions often make postoperative back pain a complex issue. Compartment syndromes can occur after surgery, but they are almost always found in he limbs, not the spine [1,2]. Although the paraspinal muscles are compartmentalized by ascia, a compartment syndrome of the paraspinal muscles has only been reported in a andful of cases [3-6]. The authors report on 2 cases of postoperative paraspinal muscle carring and sensory nerve damage that may represent a compartment syndrome. This first eport of a possibly pathognomonic physical examination finding (ie, paraspinal sensory oss), electromyogram findings, and progression of abnormal magnetic resonance imaging MRI) findings may help spine practitioners recognize and treat this rare complication of eneral surgery. This report was exempted from review by the university’s Institutional eview Board.

Risk Factors for Hip Problems Among Assembly Plant Workers

Objective The objective of this study was to determine the relative contributions of work activity (time spent standing, walking or sitting), floor surface characteristics, weight, BMI, age, foot biomechanics, and other demographic and medical history factors to the prevalence of hip disorders. Methods A cross-sectional observational study design was used to engine assembly plant workers. The main outcome measure was the finding of a hip disorder. The independent variables included baseline demographics, medical history, ergonomic exposures, psychosocial factors, shoe characteristics and foot biomechanics. Results Logistic regression revealed that increasing age, female gender, pes planus, smoking, history of a knee or hip injury, and a history of rheumatoid arthritis were significant risk factors while time on carpeted surfaces was protective. Conclusions Hip disorders are associated with a history of biomechanical trauma to the hip but also from gait abnormalities such as pes planus.

Poster 153 Inter-Rater Reliability of Physiatrists in Diagnosing Neurogenic Claudication Under an Unconstrained Clinical Situation

tion of the left shoulder and marked atrophy of the left supraspinatus and infraspinatus. Patient was referred for a course of physical therapy in addition to diagnostic work-up. MRI of the left shoulder was significant for unilateral fatty infiltration and atrophy of the supraspinatus muscle without rotator cuff pathology. MRI of the cervical spine showed multilevel spondylitic foraminal narrowing at C3-5 on the left, and C6-7 bilaterally. Multiple nerve conduction studies and EMGs were performed in order to assess course and severity. Findings were consistent with incomplete denervation of the suprascapular. Radiographs, CT arthrogram, MRI and ultrasound of left shoulder failed to show an anatomic lesion as a cause for mononeuropathy. Due to worsening symptoms and loss of function despite physical therapy, patient was taken to the operating room for left open suprascapular nerve decompression with epineurolysis and open release of the transverse ligament. Setting: Sports medicine clinic. Results or Clinical Course: On 4-week postoperative visit, patient’s pain had resolved, left shoulder strength had improved (4/5 on MMT). Discussion: The “bowstring effect” during repetitive overhead activities is a pathophysiologic mechanism proposed for isolated suprascapular nerve injury in the absence of compressive pathology (ie, mass, cyst) as previously described. Conclusions: Prompt surgical release may be a necessary intervention in preventing permanent disability and functional recovery despite lack of findings on imaging.