The purpose of this study was to investigate the effective dose of therapeutic ultrasound in the treatment of carpal tunnel syndrome on pain level, functional ability, motor and sensory nerve conduction parameters and pinch strength.

Carpal tunnel syndrome (CTS) is among the most common peripheral neuropathies causing the median nerve compression as it crosses the carpal tunnel, with an estimated prevalence of about 4 - 5% of the general population. Patients suffering from this syndrome mainly complain about paresthesia (pain, numbness, and tingling) in the innervation area of the median nerve in the hand which could be accompanied by weakness and atrophy of thenar muscles.

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper limb and a significant contributor to hand functional impairment and disability that could be treated through numerous approaches. Effective treatment options include conservative and surgical interventions.

Carpal Tunnel Syndrome (CTS) remains a puzzling and disabling condition present in 3.8% of the general population. CTS is the most well-known and frequent form of median nerve entrapment, and accounts for 90% of all entrapment neuropathies.

Physiotherapy modalities are used to help patients with CTS in many cases. They can both help to improve CTS symptoms as well as resolve the cause of the syndrome. Physiotherapy intervention may include special exercises, mobilizations, ergonomic interventions and advice for as well as electrotherapy modalities, aiming for the treatment and improvement of symptoms.

Ultrasound waves have anti-inflammatory properties, stimulating nerve regeneration and improving nerve conductivity.

The most common uses for US are to decrease soft tissue inflammation, increase tissue extensibility, enhance scar tissue remodeling, increase soft tissue healing, decrease pain, and decrease soft tissue swelling .

The issue of selecting the nature of the ultrasonic wave has not been finally resolved. A continuous wave is more often used to reduce pain and increase the elasticity of the tissue, while a pulsed wave mode is applied to reduce swelling and to eliminate inflammation. The rate of absorption, and thus the thermal effect, is based on the tissue type encountered, the frequency of the ultrasound beam, and the intensity (W/cm2) of the ultrasonic output.

Inclusion Criteria:

1. Subject's age range was 25-55 years .

2. Mild to moderate CTS, that is confirmed by neurologist or orthopedist based on results of physical examination and electrophysiological criteria; i. Mild CTS is characterized by sensory fibers involvement (sensory peak latency > 3.6 milliseconds) with no motor fiber involvement (motor distal latency < 4.1 milliseconds), provided that sensory nerve action potential (SNAP) is not absent.

   ii. Moderate CTS is characterized by involvement of both sensory and motor fibers, provided that neither of these two waves is absent .

3. Pain intensity more than 5 in visual analogue scale (VAS).

Exclusion Criteria:

1. History of any trauma on the hands, neck, and shoulders within 3 months of the study onset

2. Cervical radiculopathy, peripheral polyneuropathy, or other neurological conditions.

3. Patients suffering from severe CTS according to electrophysiological criteria

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