A randomised clinical trial comparing outcomes of a single digit volar plate injury — Buddy loops versus dorsal thermoplastic orthosis in a neutral position: study protocol

BACKGROUND: Volar plate injuries are a common hand injury and complications associated with this injury such as a fixed flexion deformity, persistent pain and oedema can have a significant impact on a person’s function. The literature reports these injuries are treated using various splinting materials such as thermoplastic, in varying degrees of proximal interphalangeal joint flexion or buddy loops. Despite volar plate injuries being reported as common, optimal non-surgical treatment of these injuries remains unclear. This study aims to investigate whether a dorsal blocking orthosis in a neutral position (0(0)) is more effective than buddy loops for a volar plate injury to the proximal interphalangeal joint in preventing a fixed flexion deformity, reducing pain, managing oedema, and promoting function. METHODS: This study is a single-centre, prospective parallel-group, single blinded (assessor), randomised clinical trial. Patients between 18–65 years, who have sustained a volar plate injury to a single digit, have adequate cognitive functioning and give written informed consent will be invited to participate in this study. Patients will be randomised to either the control group where they will be fitted with buddy loops and commence early active motion exercises or the experimental group where they will receive a dorsal thermoplastic orthosis in a neutral position and commence early active motion exercises. The primary outcome measure is passive proximal interphalangeal joint extension and secondary outcome measures include passive range of motion, total passive motion, active range of motion, total active motion, grip strength, oedema, pain, function and adherence to treatment. Assessments will be completed until 8 weeks following commencement of treatment. The sample size calculation indicates that 23 patients is required in each group. With an expected dropout rate of 25% a total of 32 patients will be enrolled in each group. DISCUSSION: This study will assist in trying to improve treatment of volar plate injuries and assist in reducing complications associated with volar plate injuries, potentially reducing the need for prolonged hand therapy. TRIAL REGISTRATION: This trial has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622001425785p). Ethical approval has been granted by the South Eastern Sydney Local Health District ethical committee (2022/ETH01697). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-023-06192-5.