Prospective Longitudinal Study of CTS

This study used a prospective longitudinal cohort design. Seventy-three patients with clinically and electrodiagnostically confirmed CTS were recruited from the surgical waiting lists at Oxford University Hospitals NHS Foundation Trust. Patients were excluded if electrodiagnostic testing revealed abnormalities other than CTS, if another medical condition affecting the upper limb and neck was present (e.g. hand osteoarthritis, cervical radiculopathy), if there was a history of significant trauma to the upper limb or neck, or if CTS was related to pregnancy or diabetes. Patients undergoing repeat carpal tunnel surgery were excluded. Whereas 60 patients underwent surgery and were included in the main cohort, 13 patients opted out of surgery after being consented, with the study team having no role in these patients’ decisions. While these patients were not the main focus of the study, we continued to follow them over time and report their data as a separate cohort. A cohort of 20 healthy volunteers (proportionally age- and gender-matched to the CTS surgery group) without any systemic medical condition, or a history of hand, arm or neck symptoms, served as healthy control subjects.
The study was approved by the London Riverside national research ethics committee (Ref 10/H0706/35), and all participants gave informed written consent in accordance with the Declaration of Helsinki. Whereas the healthy participants only attended a single session, all patients attended two appointments, one at baseline and a follow-up appointment (∼6 months after surgery/baseline appointment). In patients with CTS, the hand that was operated (surgery group) or the hand that was more affected (no-surgery group) was tested, whereas the non-dominant hand was tested in healthy controls. All clinical measurements were collected by the same experienced examiner to ensure consistency.