To complement the Research Reports in the February 2015 issue of MASSAGE Magazine. Summary: A group of massage therapists experiencing thumb pain showed increased range of motion and decreased strength of the thumb; while those without thumb pain showed increased thumb strength compared to that group.
Thumb range of motion and thumb strength measurements were taken and compared between massage practitioners with thumb pain, massage therapists without thumb pain and a group of control subjects.
The study, “Increased Range of Motion and Decreased Strength of the Thumb in Massage Practitioners with Thumb Pain,” involved massage practitioners with and without thumb pain, and a group of control subjects.
Musculoskeletal pain and loss of function may be caused by repetitive joint and tissue stress. The study’s authors said, “the demand for massage practitioners has risen,” and “because of the repetitive use of the thumb, thumb pain is the most common work-related musculoskeletal pain among massage practitioners.”
This study was conducted to compare the range of motion (ROM) and strength of the metacarpophalangeal (MP) and interphalangeal (IP) joints of massage practitioners with thumb pain, massage practitioners without thumb pain and control subjects.
Participants included 16 female massage practitioners with thumb pain and 16 female practitioners without thumb pain recruited from 16 massage centers, and 16 female control subjects that were students at Yonsei University. Participants had no injury- or inflammation-induced limitation of thumb movement, history of surgery or fracture in the upper extremity or neurologic condition in the upper extremity.
The visual analog scale (VAS) was used to measure severity and perception of thumb pain. Participants marked their pain level using a scale of “no pain” at 0 and “worst pain” at 100.
The authors said all subjects were included in the measurement of “ROM of flexion, extension and abduction in the MP joint; ROM of flexion; and extension in the IP joint of the thumb,” which involved a digital camera and SIMI motion analysis system, and “strength of the flexor pollicis brevis (FPB), extensor pollicis brevis (EPB), abductor pollicis brevis, flexor pollicis longus (FPL), and extensor pollicis longus,” involving a digital dynamometer.
Compared to control subjects, massage practitioners with and without thumb pain had significantly increased ROM of extension and abduction in the MP joint. Massage practitioners with thumb pain had an increased ROM of extension in the IP joint compared with massage practitioners without thumb pain. Massage practitioners with thumb pain were found to have significantly decreased strength of the EPB and FPL muscle compared to the other participants.
Massage practitioners without thumb pain had significantly increased EPB and FPB strength compared with massage practitioners with thumb pain and the control group participants.
Massage practitioners who engaged in repeated thumb use during work have greater thumb MP mobility, and massage practitioners with thumb pain have greater IP extension mobility than massage practitioners without thumb pain. Decreased EPB and FPL muscle strength was observed in massage practitioners with thumb pain.
The authors said, “Future study is needed to investigate whether strengthening of the EPB muscle and FPL muscle can reduce thumb pain through a longitudinal study.”
Authors: Si-hyun Kim, Oh-yun Kwon, Mi-ryung An and Yoon-shin Kim
Sources: Department of Physical Therapy, Graduate School, Yonsei University, Republic of Korea; Department of Physical Therapy, Kinetic Ergocise Based on Movement Analysis Laboratory, College of Health Science, Yonsei University, Republic of Korea; Department of Skin & Health Care, Sahm Yook Health University, Republic of Korea; and Department of Occupational & Environmental Medicine, Hanyang University, Republic of Korea. Originally published in 2014 in Industrial Health.