It will be a randomized clinical trial with a sample size of about 80 patients. It will have two study groups: the experimental group (in which 40 patients will be included) where a Z-plasty technique will be applied; and the control group (another 40 patients) who will undergo the conventional technique of complete section of the transverse carpal ligament. The main variable will be the presence or absence of post-surgical pillar pain and, as secondary variables, the recovery of grip and pincer strength and the improvement in the BCTQ score will be studied.~The study population will be patients with carpal tunnel syndrome diagnosed clinically (pain and paresthesias in the first three fingers and radial edge of the fourth finger, nocturnal paresthesias, thenar muscle atrophy, loss of thumb opposition), examination (Durkan's signs , Phalen and Tinnel positive) and with a positive electromyogram test classified as moderate or severe. As inclusion criteria, patients >18 years of age with moderate-severe carpal tunnel syndrome whose symptoms hinder the daily activities of the patient and who have failed conservative treatment will be considered. Those who have already undergone a previous surgical intervention for carpal tunnel syndrome in the same hand, who have traumatic or congenital sequelae in the hand or who do not have the capacity to understand the process or the tests to be performed will be excluded.~The total expected duration of each patient in the study will be 6 months and the following visits and procedures will be carried out: clinical study and quality questionnaires prior to surgery and post-surgical follow-up at 3-4 weeks and at 6 months in consultation, with repetition of clinical examination and quality questionnaires.~The incidence of pillar pain (defined as pain/sensation of allodynia in the area of the thenar and/or hypothenar eminence, hyperalgesia in the scar, pain when supporting the heel of the hand, dysesthesia at rest) will be analyzed applying the principle of intention to treat, using the Mann Whitney test to compare the score in the tests used.
The main objective of this study is to compare the complete section of the transverse carpal ligament with another median nerve release technique and to determine if the incidence of post-surgical pillar pain is lower for either of the two surgical techniques. As secondary objectives, we also seek to determine if the postsurgical grip and pincer strength and the Boston Carpal Tunnel Questionnaire (BCTQ) score are better for either of the two surgical techniques.