Ultrasound may replace nerve tests for carpal tunnel diagnosis

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

INCLUSION CRITERIA: Participants aged 18-60 years who meet the eligibility criteria as either healthy controls or patients with carpal tunnel syndrome (CTS) are eligible for the study. 1. Healthy Participants: * Absence of any clinical symptoms related to CTS. * Normal evaluation according to electrophysiological criteria for CTS. 2. Participants with CTS: Participants must have a diagnosis of mild or moderate CTS based on clinical findings and electrophysiological evaluation. b.1) Clinical Findings/Symptoms: b.1.1) Symptoms: (A)- Sensory symptoms in the 1st, 2nd, 3rd finger, or lateral half of the 4th finger, or in any combination of these. (B)- Symptom relief with hand-shaking or squeezing movements. (C)- Pain or paresthesia triggered by hand grip or forceful hand use. (D)- Nocturnal paresthesia causing the patient to wake from sleep. b.1.2) Diagnostic Tests/Signs: * Tinel's sign * Phalen test * Reverse Phalen test * Carpal tunnel compression test * Flick sign Clinical CTS Diagnosis: Symptoms must be present for at least three months and at least the presence of sensory symptoms (A) plus at least one of B, C, or D, together with at least one positive diagnostic test/sign, is required for clinical diagnosis. b.2) Electrophysiological Evaluation: * Mild CTS: Median-ulnar sensory peak latency difference ≥ 0.4 ms in the 4th finger, and median sensory distal latency of the 2nd finger ≥ 2.8 ms, with conduction velocity \< 50 m/s. Sensory nerve action potential (SNAP) ≥ 12 μV. * Moderate CTS: Median distal motor latency of the 2nd finger between 4 ms and 5.5 ms, with conduction velocity \< 50 m/s. Compound muscle action potential (CMAP) ≥ 5 mV. E) EXCLUSİON CRİTERİA: 1. For Participants Meeting Patient Criteria: * Participants diagnosed with mild or moderate CTS who meet any of the following criteria will be excluded: * History of physical therapy for carpal tunnel syndrome within the last 6 months. * History of injection into the carpal tunnel. * History of carpal tunnel release surgery. * Presence of thenar atrophy in the hand. * History of cardiac pacemaker implantation. * History of lymphedema in the studied extremity. * History of cervical radiculopathy. * Presence of tenosynovitis in the ipsilateral upper extremity. * Presence of another compressive neuropathy in the ipsilateral upper extremity. * History of peripheral polyneuropathy or comorbidities that may cause peripheral polyneuropathy (e.g., diabetes mellitus). * Presence of metabolic disease. * History of fracture in the hand, wrist, or forearm. * Active pregnancy. * Presence of open wounds on the wrist. * History of uncontrolled systemic disease (endocrinologic, cardiovascular, pulmonary, hematologic, hepatic, renal, active systemic inflammatory disease, and/or malignancy). * History of inflammatory rheumatic or autoimmune disease. * Distal motor latency of the median nerve \> 5.5 ms on electrophysiological evaluation. * Age \< 18 or \> 60 years. * Cognitive or mental incapacity preventing understanding or completion of questionnaires. * Anatomical variations affecting ultrasonographic assessment of the median nerve (e.g., bifid median nerve, persistent median artery). * Anatomical variations affecting electrophysiological measurements (e.g., Martin-Gruber anastomosis). 2. For Healthy İndividual Participants: Participants will be excluded if they meet any of the following criteria: * Age \< 18 or \> 60 years. * Cognitive or mental incapacity preventing understanding or completion of questionnaires. * Presence of any clinical symptoms potentially related to CTS based on established clinical criteria. * Electrophysiological findings consistent with CTS, based on defined diagnostic thresholds.