Rehabilitation for Balance and Gait Impairment in an Adolescent With Nudt2 Mutation: A Case Report

Background: Biallelic NUDT2 gene mutations cause a rare autosomal recessive neurodevelopmental disorder characterized by developmental delay, muscle atrophy, and progressive motor deficits. This complex condition often leads to significant central and peripheral nervous system involvement, resulting in highly debilitating gait and balance impairments. Objective: To describe the complex multi-system impairments and objective long-term rehabilitation outcomes of an adolescent presenting with a NUDT2 mutation and crouched gait mechanics. Methods: A 16.5-year-old male with a NUDT2 mutation and a history of lower-limb tendon surgeries completed a 6-week individualized physiotherapy program (2 sessions/week), a 1-month home program hold, and a structured re-admission phase for advanced overground and treadmill gait training. Outcome tools included the Selective Control Assessment of the Lower Extremity (SCALE), Gross Motor Function Measure (GMFM-88), Timed Up and Go (TUG), and Five Times Sit-to-Stand (5xSTS). Results: Baseline GMFM-88 was 72.2%. Post-initial intervention, isolated left knee SCALE scores improved from 1 to 2; hip (1) and distal joints (0) remained unchanged. The patient progressed from requiring upper-limb support during sit-to-stand transitions to independent execution, and weekly falls decreased from 1/week to 1/every 2 weeks. Upon re-admission, functional gains were successfully maintained, yielding a TUG of 13.4 seconds and a 5xSTS of 13.12 seconds. Conclusions: An individualized, task-specific physiotherapy protocol can drive meaningful motor adaptations and maintain functional mobility in patients with rare NUDT2 mutations, emphasizing the role of targeted impairment-based rehabilitation despite persistent genetic and structural distal deficits.