A Rare Case Report: A Thumb Lipoma causing Ape Hand Deformity in a 58-year-Old Woman at Mbale Regional Referral Hospital

Background: Ape hand deformity is an uncommon presentation, typically resulting from median nerve palsy or injury, and is rarely caused by space-occupying lesions such as lipomas. Case Presentation: We report the case of a 58-year-old woman who presented to Mbale Regional Referral Hospital with progressive weakness of thumb muscles, restricted mobility, and difficulty in gripping objects. Examination revealed thenar muscle wasting and inability to oppose, abduct, or circumduction the thumb, consistent with ape hand deformity. Imaging and intraoperative findings confirmed the presence of a Lipoma at the base of the thumb compressing the median nerve. Surgical excision (lipomectomy) with nerve decompression was performed, followed by structured physiotherapy and occupational therapy. The patient experienced significant functional recovery and improvement in quality of life. Conclusion: This case highlights the importance of considering rare etiologies such as lipomas in patients with atypical presentations of median nerve palsy. Early diagnosis and comprehensive management, including surgical intervention and rehabilitation, are essential for optimal functional outcomes.