Recurrence of Extremity Joint Contracture After Z-Plasty Versus Full-Thickness Skin Graft

Background Deep (full-thickness) burns over joints frequently lead to scar contractures that restrict range of motion (ROM), impair function and independence in daily activities, and reduce quality of life. Approximately one-third of burn patients have at least one contracture at hospital discharge. Despite surgical release, recurrence remains a clinical problem, with a pooled recurrence rate of about 10% reported for hand burn contractures. Z-plasty (local transposition flaps that lengthen the scar axis without donor tissue) and full-thickness skin graft (FTSG; coverage of the post-release defect with full-thickness skin from a donor site) are the two most commonly used techniques for releasing extremity contractures. Comparative evidence on recurrence is inconsistent: some studies report lower recurrence after Z-plasty and others report no significant difference. This variation may reflect differences in anatomical site, contracture morphology (linear band versus broad planar defect), burn severity, operative technique, rehabilitation adherence, and length of follow-up. Evidence specific to extremity joint contractures remains limited.

Objectives The primary objective is to compare the recurrence rate of extremity joint contracture after surgical excision/release with Z-plasty versus FTSG. Secondary objectives are to describe the demographic and clinical characteristics of patients in each group, to determine the recurrence rate within each group, and to identify factors associated with contracture recurrence.

Study Design This is a single-center, observational, analytic, retrospective cohort study based on review of existing medical records. Patients are grouped according to the closure technique documented in the operative report (Z-plasty alone or FTSG alone). Treatment allocation was determined by routine clinical care; no intervention is assigned or administered as part of this study.

Setting and Study Period Department of Plastic, Reconstructive and Aesthetic Surgery, Dr. Moewardi General Hospital / Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia. Medical records from 2016 to 2026 will be reviewed. Data collection and analysis are planned for July to November 2026.

Sampling Total (consecutive) sampling will be used: all patients meeting the eligibility criteria during the study period will be included, given the limited number of cases at a single institution. No formal a priori sample size calculation is performed.

Variables The exposure is the surgical technique (Z-plasty or FTSG). The outcome is contracture recurrence, defined as loss of the corrected ROM or development of a tethering scar band requiring revision, assessed by goniometric evaluation at least 6 to 12 months postoperatively. Potential confounders recorded include age, anatomical joint involved, depth of the initial burn, duration of follow-up, adherence to postoperative rehabilitation (physiotherapy, splinting, pressure garments), and comorbidities such as diabetes mellitus.

Data Collection and Management Data will be abstracted from medical records using a standardized, investigator-designed data collection form covering de-identified patient characteristics, clinical characteristics, operative technique, pre- and postoperative ROM, and recurrence status at the last recorded follow-up. Data will be verified and cleaned for completeness and internal consistency before analysis. Patients with incomplete records or loss to follow-up before the minimum recurrence-assessment period will be excluded, so the primary analysis will be a complete-case analysis.

Statistical Analysis Descriptive (univariate) statistics will summarize participant characteristics. Recurrence proportions between the Z-plasty and FTSG groups will be compared using the chi-square test, or Fisher's exact test when any expected cell count is less than 5. If appropriate, multivariable logistic regression will be performed to adjust for potential confounders. Statistical significance is set at p \< 0.05.

Ethics The study will be submitted for approval to the Health Research Ethics Committee of Dr. Moewardi General Hospital before data collection. Only secondary data from medical records are used, no direct intervention involves participants, and all data will be anonymized to protect patient confidentiality in accordance with Indonesian medical records regulations.