Effect of prior experience and task stability on the intrinsic muscle activity of the thumb

Prevalence of work-related musculoskeletal hand and wrist disorders in physiotherapists

OBJECTIVES

This study examines the prevalence of hand and wrist symptoms and diagnosed disorders in physiotherapists in Slovakia. The aim was to identify risk factors such as occupational settings type, number of patients treated per day and years of clinical practice, and to determine preferred methods of treatment.

METHOD

The group of 107 physiotherapists (28 men and 79 women) participated in the study. All participants completed a questionnaire created for the purpose. It contained demographic data, years of clinical practice and the questions to determine the presence of various symptoms and injuries to the hand and wrist due to a long-lasting overuse of the hand musculoskeletal system.

RESULTS

Twelve (11.2%) physiotherapists of the observed group did not show any symptoms of functional impairment, and 32 (29.9%) were without any specific hand or wrist disorders. The results confirmed a significant prevalence of symptoms of functional impairment (mean 2.4) and disorders (mean 1.3) with an increased risk in the physiotherapists working in a combined type of occupational settings (outpatient physical therapy and hospital facilities). The most frequently reported symptoms were hand pain (70%) and reduced muscle strength (45.7%). The most frequently reported diagnosed disorder was hand tendonitis (26.2%). The results confirmed the statistically significant correlation (α = 0.05) between the years of clinical practice and the number of identified symptoms and disorders (p < 0.001) as well as between the number of patients treated per day and the number of symptoms (p = 0.007). Hand immobilization (28.6%) and manual therapy (24.4%) were preferred methods of treatment. Surgical intervention was required in 2.2% of hand injuries.

CONCLUSIONS

In physiotherapists, long-term performance of manual techniques indicates the development of musculoskeletal disorders of the hand and wrist.

Kinematic Analyses of the Thumb during Simulated Posteroanterior Glide Mobilization

Objective

Thumb problems are common in some health professionals such as physical therapists. The purpose of this case-control study is to investigate the influence of clinical experience and different mobilization techniques on the kinematics of the thumb.

Methods

Twenty-three participants without exposure to manual techniques (the Novice Group) and fifteen physical therapists with at least 3 years of orthopedic experience (the Experienced Group) participated. The kinematics of the thumb while performing 3 different simulated posteroanterior (PA) glide mobilization techniques on a load cell was monitored. These 3 techniques were: 1) unsupported, 2) with digital support and 3) with thumb interphalangeal joint supported by the index finger. The amount of forces exerted were 25% to 100% of maximum effort at 25% increments. The main effects of experience and technique on thumb kinematics were assessed.

Results

Both experience and technique had main effects on the flexion/extension angles of the thumb joints. Experienced participants assumed a more flexed position at the carpometacarpal (CMC) joint, and the novice participants performed with angles closer to the neutral position (F = 7.593, p = 0.010). Participants’ metacarpophalangeal (MCP) joints were in a more flexed position while performing PA glide with thumb interphalangeal (IP) joint supported by the index as compared to the other two techniques (p < .001).

Conclusions

Negative correlations were generally obtained between the sagittal plane angles of adjacent thumb joints during mobilization/manipulation. Therapists are recommended to treat patient with more stable PA glide mobilization techniques, such as PA glide with thumb interphalangeal joint supported by the index finger, to prevent potential mobilization-related thumb disorders.