X-linked hypophosphatemia and spinal cord compression: a systematic review and illustrative case

STUDY DESIGN: Systematic review. OBJECTIVE: X-linked hypophosphatemia (XLH) is a rare genetic disorder characterized by impaired phosphate homeostasis due to renal phosphate wasting. It leads to osteomalacia and skeletal abnormalities and represents the most common inherited cause of vitamin D-resistant rickets. In some patients, heterotopic ossification of the ligamentum flavum and paravertebral ligaments may result in spinal cord compression and myelopathy. Due to its rarity, large case series evaluating patient characteristics and surgical outcomes are lacking. METHODS: We conducted a PRISMA-P based systematic review on spine surgery and X-linked hypophosphatemia from 1960 to 2022. Twenty-five studies were included, comprising 32 clinical cases. An illustrative case is also presented. RESULTS: Thirty-two patients (16 females and 16 males) with spinal cord compression due to XLH were included in this systematic review. Thirty out of 32 patients underwent surgery (one death and one refusal of surgery). The mean age of onset of symptoms was 41 years. 83% (25/30) had reduction of their symptoms after surgery, and 57% (17/30) had full recovery post-operatively. The mean follow-up time was 42 months. The recurrence rate was 13% (4/32). One case of suboccipital decompression was complicated by cranial nerve palsy. CONCLUSION: Patients with XLH requiring surgery appear to have good functional outcomes and low complication rates. However, recurrence is not uncommon, supporting the need for long-term follow-up.