Article

OBJECTIVES: To investigate (1) the relation between needle diameter and treatment
efficacy of myofascial pain syndrome and (2) the relation between needle diameter
and pain intensity during injection. DESIGN: Randomized controlled trial.
SETTING: University-affiliated tertiary-care hospital. PARTICIPANTS: Volunteers
(N=77) with myofascial pain syndrome affecting upper- and middle-trapezius
muscles with at least 3 months' duration of pain. INTERVENTION: Participants were
randomly assigned to receive trigger point injections on 1 side of the trapezius
with a 21-, 23-, or 25-gauge needle. After a 1-time injection, participants were
followed up for 14 days. Participants and the assessor were blinded for group
assignment. MAIN OUTCOME MEASURES: Treatment efficacy was measured with the
visual analog scale (VAS; at pretreatment, and posttreatment on days 1, 4, 7, 14)
for neck and upper-back pain, the Neck Disability Index (NDI; at pretreatment,
and posttreatment on days 7, 14), and the Medical Outcomes Study 36-Item
Short-Form Health Survey (SF-36, at pretreatment and posttreatment on days 7, 14)
for health-related quality of life. Pain intensity during injection was evaluated
immediately after injection with VAS. RESULTS: VAS scores for posttreatment on
days 4, 7, and 14 decreased significantly compared with pretreatment scores in
all groups; NDI scores on days 7 and 14 decreased significantly compared with
pretreatment scores in all groups; SF-36 scores on days 7 and 14 decreased
significantly compared with pretreatment scores in the 21- and 23-gauge needle
groups; and SF-36 score on day 14 showed significant difference between the 21-
and 25-gauge needle groups. For pain intensity during injection, VAS scores
indicated no significant difference between the 3 groups. CONCLUSIONS: No
difference between the needle types was observed in terms of VAS or NDI, or in
terms of pain intensity felt by patients during injection. In terms of SF-36
scores, injections with 21- or 23-gauge needles were found to be more effective.
However, a well-controlled investigation is needed to explore the effect of
needle thickness on health-related quality of life.

Langue : ANGLAIS