Electrophysiological and Functional Recovery After Carpal Tunnel Release (ELECTRO-CTS)

Relationship Between Electrophysiological Recovery of the Median Nerve and Clinical and Functional Outcomes After Carpal Tunnel Release: A Prospective Observational Cohort Study

Carpal tunnel syndrome occurs when the median nerve is compressed at the wrist. It can cause pain, numbness, tingling, reduced hand strength, and difficulty performing daily activities. Carpal tunnel release surgery is commonly performed when symptoms do not improve with conservative treatment or when nerve compression is severe. However, recovery after surgery may differ between patients, and improvement in nerve conduction may not occur at the same rate as improvement in symptoms and hand function.

The purpose of this prospective observational study is to examine the relationship between electrophysiological recovery of the median nerve and clinical and functional recovery after carpal tunnel release surgery. Adults who are already scheduled to undergo primary carpal tunnel release as part of their routine clinical care will be invited to participate. The decision to perform surgery will be made by the treating physician independently of study participation.

Participants will undergo clinical and functional assessments before surgery and at postoperative week 8 These assessments will include questionnaires about carpal tunnel symptoms and upper-extremity function, pain severity, grip and pinch strength, sensory testing, and clinical examination. Nerve conduction studies will be evaluated before surgery and at postoperative month 3.

The study will assess whether changes in median nerve conduction are associated with changes in symptoms, upper-extremity function, pain, hand strength, and sensory function. The possible effects of age, sex, body mass index, symptom duration, diabetes, and preoperative electrophysiological severity on recovery will also be examined. No experimental drug, device, surgical technique, or additional treatment will be assigned as part of this study.

Study Overview

• Status: Not yet recruiting
• Conditions: Carpal Tunnel Syndrome (CTS)
• Intervention / Treatment: Procedure: Primary Carpal Tunnel Release Surgery

Detailed Description

Carpal tunnel syndrome is the most common peripheral nerve entrapment neuropathy of the upper extremity and results from compression of the median nerve within the carpal tunnel. Patients may experience numbness, tingling, nocturnal paresthesia, pain, sensory loss, reduced grip strength, and, in advanced cases, thenar muscle weakness or atrophy. These impairments may negatively affect sleep, occupational performance, daily activities, and overall upper-extremity function.

Carpal tunnel release surgery aims to decompress the median nerve and is generally performed in patients who do not obtain adequate benefit from conservative treatment or who have progressive neurological or electrophysiological abnormalities. Although improvements in pain, paresthesia, and hand function are commonly observed after surgery, the rate and extent of recovery may vary between patients. Clinical improvement may also occur at a different rate from electrophysiological recovery of the median nerve.

This is a single-center, prospective observational cohort study involving adults with clinically and electrophysiologically confirmed carpal tunnel syndrome who are scheduled to undergo primary carpal tunnel release surgery as part of routine clinical care. The decision to perform surgery and the selection of the surgical technique will be made by the treating physician independently of participation in the study. Participation will not influence the surgical decision or the participant's routine treatment. No experimental intervention or additional treatment will be assigned by the investigators.

Only the surgically treated hand will be included in the analysis. For participants with bilateral carpal tunnel syndrome who undergo unilateral surgery during the study period, the operated hand will be evaluated. Two hands from the same participant will not be analyzed as independent observations.

Clinical and functional evaluations will be performed at baseline before surgery and at postoperative week 8. The evaluations will include the Boston Carpal Tunnel Questionnaire, Quick Disabilities of the Arm, Shoulder and Hand questionnaire, Numeric Rating Scale for pain, grip strength, pinch strength, Semmes-Weinstein monofilament testing, static two-point discrimination, and Tinel and Phalen tests.

Standard nerve conduction study findings obtained during routine clinical evaluation will be recorded at baseline and postoperative month 3. Electrophysiological variables will include median nerve distal motor latency, compound muscle action potential amplitude, sensory distal latency, sensory nerve action potential amplitude, and sensory nerve conduction velocity. Electrophysiological severity will be classified using the Bland neurophysiological grading scale. Needle electromyography will not be mandatory for study participation and will only be performed when clinically indicated as part of routine care.

The primary objective is to determine whether electrophysiological changes in the median nerve between baseline and postoperative month 6 are associated with changes in carpal tunnel symptoms and upper-extremity function. Particular emphasis will be placed on changes in distal motor latency and sensory nerve conduction velocity and their relationships with changes in the Boston Carpal Tunnel Questionnaire and QuickDASH scores.

Secondary analyses will examine the relationships between electrophysiological recovery and changes in pain severity, grip strength, pinch strength, monofilament sensation, and two-point discrimination. The study will also investigate whether demographic and clinical factors, including age, sex, body mass index, symptom duration, hand dominance, operated side, occupational hand use, diabetes mellitus, and preoperative electrophysiological severity, are associated with postoperative clinical, functional, or electrophysiological recovery.

The planned enrollment is approximately 70 to 100 participants. Findings from this study may help clarify the extent to which objective nerve conduction recovery reflects patient-reported and performance-based recovery after carpal tunnel release surgery.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age between 18 and 75 years.
• Clinical and electrophysiological diagnosis of carpal tunnel syndrome.
• Scheduled to undergo primary carpal tunnel release surgery based on routine clinical evaluation.
• Availability of a preoperative nerve conduction study.
• Ability to understand and complete the study assessments and questionnaires.
• Ability to read and understand Turkish.
• Willingness to participate and provide written informed consent.
• Ability and willingness to attend the planned postoperative follow-up assessments.

For participants with bilateral carpal tunnel syndrome who undergo unilateral surgery during the study period, only the operated hand will be included in the study. Two hands from the same participant will not be analyzed as independent observations.

Exclusion Criteria:

• Previous carpal tunnel release surgery on the study hand.
• Planned revision carpal tunnel surgery.
• Electrophysiological evidence of generalized polyneuropathy.
• Another peripheral neuropathy affecting the median nerve or function of the study hand.
• Active cervical radiculopathy or brachial plexopathy.
• A central or peripheral neurological disorder that substantially affects upper-extremity function.
• History of major trauma or surgery involving the study hand or wrist that may affect outcome assessments.
• Active inflammatory rheumatologic disease.
• Pregnancy.
• Uncontrolled systemic disease that may interfere with surgery, assessment, or follow-up.
• Cognitive or communication impairment that prevents completion of the study assessments.
• Inability to complete the planned postoperative follow-up assessments.

Participants with controlled diabetes mellitus will not be excluded solely because of diabetes. However, participants with electrophysiologically confirmed generalized polyneuropathy will be excluded. Diabetes status will be recorded and considered as a potential confounding variable in the analyses.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: Carpal Tunnel Release Group; Participants with clinically and electrophysiologically confirmed carpal tunnel syndrome who are scheduled to undergo primary carpal tunnel release surgery as part of routine clinical care will be included in this single study arm. The decision to perform surgery and the surgical technique will be determined by the treating physician independently of study participation. Clinical and functional assessments will be performed before surgery and at postoperative week 8. Median nerve conduction findings will be evaluated before surgery and at postoperative month 3. No experimental drug, device, surgical technique, or additional treatment will be administered as part of the study.

Procedure: Primary Carpal Tunnel Release Surgery; Participants will undergo primary carpal tunnel release surgery as part of their routine clinical care. The procedure aims to decompress the median nerve by releasing the transverse carpal ligament. The decision to perform surgery, the timing of surgery, and the surgical technique will be determined by the treating physician independently of study participation. The study will not require an experimental surgical technique or any modification of the participant's standard treatment. Participants will undergo clinical and functional follow-up assessments, and median nerve conduction findings will be evaluated before surgery and at postoperative month 6.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Median Nerve Distal Motor Latency	Median nerve distal motor latency will be measured by a standardized nerve conduction study and recorded in milliseconds (ms). Change will be calculated as the postoperative month 6 value minus the preoperative value. A reduction in distal motor latency indicates electrophysiological improvement.	Baseline and postoperative week 8

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Median Nerve Sensory Nerve Conduction Velocity	Median nerve sensory nerve conduction velocity will be measured by a standardized nerve conduction study and recorded in meters per second (m/s). Change will be calculated as the postoperative month 6 value minus the preoperative value. An increase in sensory nerve conduction velocity indicates electrophysiological improvement.	Baseline and postoperative week 8
The Boston Carpal Tunnel Questionnaire consists of the Symptom Severity Scale and the Functional Status Scale. Each item is scored from 1 to 5, and the mean score is calculated separately for each subscale. Higher scores indicate greater symptom severity	The Boston Carpal Tunnel Questionnaire consists of the Symptom Severity Scale and the Functional Status Scale. Each item is scored from 1 to 5, and the mean score is calculated separately for each subscale. Higher scores indicate greater symptom severity or functional limitation. Change will be calculated relative to the baseline score. A reduction in score indicates clinical and functional improvement.	Baseline, postoperative week 8
Change in Quick Disabilities of the Arm, Shoulder and Hand Score	Upper-extremity disability will be assessed using the Quick Disabilities of the Arm, Shoulder and Hand questionnaire. The total score ranges from 0 to 100, with higher scores indicating greater disability. Change will be calculated relative to the baseline score. A reduction in score indicates improvement in upper-extremity function.	Baseline, postoperative week 8
Change in Median Nerve Sensory Nerve Action Potential Amplitude	Description: Median nerve sensory nerve action potential amplitude will be measured by nerve conduction study and recorded in microvolts (µV). Change will be calculated as the postoperative month 3 value minus the baseline value. A higher amplitude generally indicates better sensory nerve function.	Time Frame: Baseline and postoperative month 3
Change in Median Nerve Compound Muscle Action Potential Amplitude	Description: Median nerve compound muscle action potential amplitude will be measured by nerve conduction study and recorded in millivolts (mV). Change will be calculated as the postoperative month 3 value minus the baseline value. A higher amplitude generally indicates better motor nerve function.	Time Frame: Baseline and postoperative month 3
Change in Numeric Rating Scale Pain Score	Description: Hand and wrist pain intensity will be evaluated using an 11-point Numeric Rating Scale ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. A reduction in score indicates improvement.	Baseline, postoperative week 8, month 3,
Change in Semmes-Weinstein Monofilament Sensory Threshold	Description: Touch-pressure sensation will be evaluated using Semmes-Weinstein monofilaments at the thumb, index finger, and middle finger of the operated hand. The lowest monofilament level perceived at each location will be recorded. A lower sensory threshold indicates better touch-pressure sensitivity.	Baseline, postoperative week 8, month 3,
Change in Static Two-Point Discrimination Distance	Description: Static two-point discrimination will be evaluated at the index and middle fingertips of the operated hand. The shortest distance at which two separate points can be distinguished will be recorded in millimeters (mm). A reduction in distance indicates improved sensory discrimination. Time Frame: Baseline, postoperative week 6, month 3,	Time Frame: Baseline, postoperative week 8, month 3,

Collaborators and Investigators

• Sponsor: Istanbul Medipol University Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: September 1, 2026
• First Submitted That Met QC Criteria: September 1, 2026
• First Posted (Actual): September 4, 2026

Study Record Updates

• Last Update Posted (Actual): September 4, 2026
• Last Update Submitted That Met QC Criteria: September 1, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Hand Function; Carpal Tunnel Release; Median Nerve; QuickDASH; Electrophysiological Recovery
• Additional Relevant MeSH Terms: Nervous System Diseases; Wounds and Injuries; Neuromuscular Diseases; Peripheral Nervous System Diseases; Median Neuropathy; Mononeuropathies; Nerve Compression Syndromes; Cumulative Trauma Disorders; Sprains and Strains; Carpal Tunnel Syndrome
• Other Study ID Numbers: IMU-CTS-2026-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No