The Effect of Different Molecular Weight of HA for Carpal Tunnel Syndrome

Recently, nerve hydrodissection is utilized to assist ultrasound-guided nerve injection and studies recommend its clinical benefit for peripheral entrapment neuropathy. Hyaluronic acid (HA) can decrease the post-surgery adhesion of soft tissue and nerve but its clinical application in clinical practice is very rare. We just proved that single HA injection have short-term effectiveness in mild-to-moderate carpal tunnel (CTS) cases and this finding may hint the therapeutic effectiveness of nerve hydrodissection for CTS depend on absorption time of solution. In addition, no study compare different weight of HA for nerve injection so far. Hence, the purpose of this study aim to compare different weight of HA for CTS and whether hydrodissection effect depend on the absorption time of solution or not.

Participants established with diagnosis of mild-to-moderate CTS will been randomly assigned to high molecular weight HA (Aragan Plus, 20 mg/2 ml, 3000kDa) or low molecular weight HA (ARTZDispo, 25 mg/2.5 ml, 600-1200kDa) groups. With ultrasound guidance, total two-sessions of high or low molecular weight HA with one week interval will been injected into intra-carpal region. The Boston Carpal Tunnel Syndrome Questionnaire is assigned as primary outcome. The secondary outcomes encompass visual analog scale, electrophysiological studies, cross-sectional area of the median nerve, mobility of median nerve and absorption time of HA. The assessment is performed prior injection and at 2 week, 1, 2, 3 and 6 months post-injection.

Ultrasound-guided hydrodissection with high molecular weight hyaluronic acid between carpal tunnel and median nerve (total 2 times with one-week interval)

Ultrasound-guided hydrodissection with low molecular weight hyaluronic acid between carpal tunnel and median nerve (total 2 times with one-week interval)

Sono-guided injection with hyaluronic acid (Aragan Plus, 20 mg/2 ml, 3000kDa) between carpal tunnel and median nerve

Sono-guided injection with hyaluronic acid (ARTZDispo, 25 mg/2 ml, 600-1200kDa) between carpal tunnel and median nerve

Change from baseline of severity of symptoms and functional status on 2nd week, 1st, 3rd, 6th month after injection

Boston carpal tunnel syndrome questionnaire (BCTQ) is a frequently used patient-based questionnaire for measurement of CTS which encompasses two components. In total, 11 questions and 8 items were evaluated to rate the symptom severity scale (SSS) and functional status scale (FSS), respectively. Both subscales range from 1 to 5 with a higher score indicating a higher degree of disability. The mean of total SSS and FSS divided with each item score were used for further analysis.

Digital pain severity or paresthesia/dysthesia was evaluated using visual analog scale (VAS). Pain score scale ranged from 0 to 10, with 10 indicating the most severe pain.

Change from baseline of cross-sectional area of the median nerve on 2nd week, 1st, 3rd, 6th month after injection

Using the musculoskeletal sonogram to measure the cross-sectional area of the median nerve before treatment and multiple time frame after treatment.

Change from baseline of conduction velocity, amplitude of median nerve on 2nd week, 1st, 3rd, 6th month after injection

electrophysiological study of the median nerve before treatment and multiple time frame after treatment.

Using the musculoskeletal sonogram to measure the mobility of the median nerve before treatment and multiple time frame after treatment.

Inclusion Criteria: Age between 20-80 year-old. Diagnosis was confirmed using an electrophysiological study Exclusion Criteria: Cancer Coagulopathy Pregnancy Inflammation status Cervical radiculopathy Polyneuropathy, brachial plexopathy Thoracic outlet syndrome Previously undergone wrist surgery or steroid injection for CTS

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