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MeDe Study: Comparing Median Nerve Decompression at the Carpal Tunnel Alone Versus Median Nerve Decompression at Both the Carpal Tunnel and Lacertus Fibrosis in Adults With Carpal Tunnel Syndrome

MeDe Study: A Randomized Controlled Trial Comparing Median Nerve Decompression at the Carpal Tunnel Alone Versus Median Nerve Decompression at Both the Carpal Tunnel and Lacertus Fibrosis in Adults With Carpal Tunnel Syndrome

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07594821
Acronym
MeDe
Enrollment
110
Registered
2026-05-19
Start date
2026-05-06
Completion date
2028-02-01
Last updated
2026-06-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Carpal Tunnel Syndrome (CTS), Lacertus Syndrome

Keywords

carpal tunnel syndrome, proximal median nerve compression, lacertus syndrome, double crush, nerve decompression, carpal tunnel release, lacertus release.

Brief summary

Carpal tunnel syndrome (CTS) is a condition that can cause pain, numbness, or tingling in the hand and wrist. The most common surgery for CTS is called carpal tunnel release, which aims to relieve pressure on the main nerve in the wrist. However, after this surgery, some patients (up to 4 out of 10) still have symptoms, and about 1 in 8 may need another surgery. One reason symptoms can continue is that the nerve may also be compressed higher up in the arm, near a ligament called the Lacertus fibrosus. Releasing this area might help, but it is often not checked or treated during the first surgery because current tests (like physical exams, nerve studies, and ultrasounds) cannot reliably detect it. This study is comparing two approaches for people with CTS: 1. Standard surgery - only releasing the carpal tunnel. 2. Extended surgery - releasing both the carpal tunnel and the Lacertus fibrosus. The goal is to see which surgery helps patients feel better and have fewer symptoms in the hand and wrist after treatment.

Detailed description

Carpal tunnel release is the most commonly performed surgical procedure in patients diagnosed with carpal tunnel syndrome (CTS). Nevertheless, up to 43% of patients experience residual symptoms, necessitating secondary surgical interventions in approximately one out of eight carpal tunnel releases. These residual symptoms may be attributable to proximal median nerve compression (PMNC), which can potentially be alleviated by performing a Lacertus release. However, diagnosing PMNC poses a challenge, as standard diagnostic tools like physical examination, electromyography (EMG) and ultrasound lack the specificity to distinguish between CTS and PMNC. Consequently, PMNC often goes undetected and untreated during initial evaluations. This randomised trial compares patient reported outcomes following median nerve decompression at the carpal tunnel alone versus median nerve decompression at both the carpal tunnel and the Lacertus fibrosus in individuals with CTS.

Interventions

Carpal tunnel release is a surgical procedure to treat carpal tunnel syndrome by cutting the ligament (transverse carpal ligament) covering the wrist's carpal tunnel. This action relieves pressure on the median nerve, alleviating pain, numbness, and weakness in the hand. It is usually an outpatient procedure done under local anesthesia.

PROCEDURECombined carpal tunnel and lacertus release

A transverse incision is made on the forearm's volar (anterior) aspect, approximately 3cm distal of the elbow crease. This incision is placed over the palpable brachioradialis and biceps tendon. The subcutaneous tissue is dissected to expose the fascia overlying the flexor pronator muscles. The brachial fascia is identified and incised to reveal the underlying Lacertus fibrosus (also known as the bicipital aponeurosis). The Lacertus fibrosus is a tendinous band extending from the biceps tendon medially across the forearm. Care is taken to avoid injury to the underlying structures, particularly the median nerve, which lies deep and slightly medial to the Lacertus fibrosus. The Lacertus fibrosus is incised transversely. The surgeon ensures that the median nerve is fully decompressed and that there are no remaining constrictive bands. It is usually an outpatient procedure done under local anesthesia.

Sponsors

Maasstad Hospital
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patients being at least 18 years or older * CTS confirmed by EMG or nerve ultrasound * Patient opts for surgical treatment

Exclusion criteria

* Previous surgical decompression of the median nerve at the ipsilateral wrist or forearm * Severe thenar atrophy: Examination of the thenar is based on clinical observation. The presence of thenar muscle atrophy is scored as none, mild, or severe. * Simultaneous nerve decompression in the ipsilateral arm (e.g. cubital tunnel, Guyon and radial nerve release. * Neurological disorders affecting peripheral nerves (e.g. spinal cord compression or injury, muscular dystrophy, dystonia, ALS) * Malunion of the distal radius * Impaired hand function * Pregnancy * Inability to complete study forms due to insufficient comprehension of the Dutch language

Design outcomes

Primary

MeasureTime frameDescription
Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQ SSS)At twelve months follow-upScores range from 1 to 5. A higher score indicates a more severe level of impairment or discomfort.

Secondary

MeasureTime frameDescription
Boston Carpal Tunnel Questionnaire Functional Status Scale (BCTQ FSS)From enrollment until 12 months of follow-upScores range from 1 to 5. A higher score indicates a more severe level of impairment or discomfort.
Anchor questionsAt 12 months follow-upRegarding patient satisfaction to analyse minimal clinically important difference (MCID)
Number of participants with residual, persistent en recurrent CTS symptomsFrom 6 weeks after surgery until 12 months of follow-up
Pillar painFrom 6 weeks after surgery until 12 months of follow-upThe presence of tenderness or pain in the thenar or hypothenar area around the hook of the hamate and the unciform process of the trapezium
Number of participants undergoing secondary surgeryFrom 6 weeks until 12 months of follow-up.This includes, but is not limited to, nerve decompression, internal or external neurolysis, and flap reconstruction in the ipsilateral arm.
Number of participants that experienced complications or adverse eventsFrom enrollment until 12 months of follow-up.Such as infection, seroma, and tendon and neurovascular damage.
(Return to) work using the QuickDASH work module.From enrollment until 6 months of follow-up.
SensibilityFrom enrollment until 12 months of follow-up.Monofilament test on the tuft of the 3rd digit and the proximal thenar. The tuft of the 5th digit and the distal thenar will be measured and used as a reference.
Tip-pinch strengthFrom enrollment until 12 months of follow-upTip-to-tip pinch strength of the first and second digit will be measured with a baseline pinch gauge.
Cost-effectiveness of interventionFrom enrollment until 12 months of follow-upMeasured with health care resource utilisation and costs (iMCQ, iPCQ).
5-level EuroQol (EQ-5D-5L): Quality of lifeWill be assessed at baseline and at 12 months of follow-up.Will be assessed using the 5-level EuroQol (EQ-5D-5L) questionnaire.
Physical examinationFrom enrollment until 12 months of follow-up.OK-sign, FLP and FDP2 strength separately (compared to contralateral hand). Scratch collapse test over the carpal tunnel and Lacertus fibrosis (positive or negative). Phalen and Tinel test (positive or negative).
Exploratory ultrasoundWill be assessed at baseline and 3 months.Changes in median nerve cross-sectional diameter (mm) to evaluate postoperative changes in nerve size over time, measured by nerve ultrasound.

Countries

Netherlands

Contacts

CONTACTSebastian Poggio Voormolen, BSc, PhD candidate
PoggioVoormolenS@maasstadziekenhuis.nl+31 6 46560865

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 27, 2026