This study was a prospective randomized double-blind clinical trial conducted at the Physical Medicine and Rehabilitation Clinic of a local research and training hospital in Turkey from October 2023 and May 2024. Patients diagnosed with CTS were classified into three groups: severe, mild, and moderate CTS, based on the results of electrophysiological tests. An ultrasound-guided 5% Dextrose in Water injection was performed. The primary outcome measurement was the Visual Analog Scale (VAS), while secondary measurements were the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) and the Dolour Neuropathic en 4 Questions (DN4) questionnaire. The measurements were performed before the injection and at the first week, first month and third month follow-up times. The distribution of data within groups was examined using the Shapiro-Wilk test and Q-Q plots. The study also analyzed temporal changes, group differences, and intergroup changes using repeated measures ANOVA models.

Inclusion Criteria:

1. Paresthesia/dysesthesia, painful swelling with clumsy weakness of the hand exacerbated by sleep or repetitive use of the wrist, and relieved by shaking the hand with postural change.
2. Sensory loss with numbness in the median nerve-innervated regions of the hand.
3. Weakness with atrophy of the median nerve-innervated thenar muscles.
4. Positive Phalen's test and/or Tinel's sign.
5. The diagnosis should be confirmed with electrodiagnostic studies.

Exclusion Criteria:

1. History of cervical myelomalacia, polyneuropathy, brachial plexopathy, or thoracic outlet syndrome.
2. History of systematic infection, and rheumatologic disorders.
3. Previous steroid injection for carpal tunnel syndrome.