1. Department of Physical Medicine and Rehabilitation, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, No. 325, Sec. 2, Cheng-Kung Road, Neihu District, Taipei, Taiwan, Republic of China.
2. Department of Physical Medicine and Rehabilitation, Taichung Armed Forces General Hospital, No. 348, Sec. 2, Chungshan Road, Taiping District, Taichung City, Taiwan, Republic of China.
3. Integrated Pain Management Center, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, No. 325, Sec. 2, Cheng-Kung Road, Neihu District, Taipei, Taiwan, Republic of China.
4. The Hong Kong Institute of Musculoskeletal Medicine, Hong Kong.
5. Department of Family Medicine, the Chinese University of Hong Kong, Hong Kong.
6. Department of Family Medicine, the University of Hong Kong, Hong Kong.
Background: This study is to compare the efficacy of short-axis hydrodissection with long-axis hydrodissection for patients with mild-to-moderate carpal tunnel syndrome (CTS).
Methods: Forty-seven patients with mild-to-moderate CTS were enrolled in a prospective, randomized, single-blinded, controlled trial (6 months follow-up). With ultrasound guidance, patients in both groups (short-axis or long-axis groups) were injected with normal saline (5 mL per session). Assessments were performed before and 2 weeks after the injection, as well as at 1, 3, and 6 months post-intervention. The primary outcome measure was the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) score and secondary outcomes included the cross-sectional area of the median nerve and electrophysiological studies.
Results: Forty-four patients (21 wrists in the short-axis group and 23 wrists in the long-axis group) completed the study. Compared with the baseline, both groups showed improved BCTQ and cross-sectional area at all follow-up assessments (p<0.05). The short-axis group was not more effective except significant improvements in BCTQ-severity and BCTQ-function 1 month post-injection compared to the long-axis group (p = 0.031 and p = 0.023, respectively).
Conclusions: Both short- and long-axis hydrodissection were effective for patients with mild-to-moderate CTS and the short-axis approach was not more effective than long-axis injection. Further studies with larger sample sizes, multiple injections, and larger injection volume are encouraged in the future.
Keywords: Carpal tunnel syndrome, hydrodissection, short-axis, long-axis