Management of Metabolic Bone Disease in Children

Initial Management at Presentation

• Multidisciplinary team management: Children with metabolic bones disorders should be managed in the context of a multidisciplinary team familiar with the assessment, natural history, treatment, and follow-up of these conditions (26). Such a team includes a metabolic disease physician, a physical therapist, and a geneticist.

Radiological surveillance

Surveillance imaging for children with metabolic bone diseases is indicated for the following reasons:

• Rare and poorly understood: These anomalies are rare, and the natural history of the spinal abnormalities is not completely understood.
• Multiple joint changes: Children with metabolic bone disease frequently have multiple joint involvement, making neurological evaluation difficult.
• Severe cord compression: Particularly in young children, severe spinal cord compression can occur without obvious symptoms.
• MRI is the best surveillance imaging modality: Although there is no class I evidence to indicate the most appropriate frequency of imaging, at least annual whole spine MRI is advised.

Adjunctive Therapies

Depending upon the particular disease, the following adjunctive therapies might need to be considered:

• Bone marrow transplantation: Bone marrow transplantation is currently recommended only for mucopolysaccharidosis type I (Hurler syndrome). Some patients with type II disease (Hunter disease) have been successfully treated with bone marrow transplantation. Bone marrow transplantation has to be performed before 2 years of age.
• Enzyme replacement therapy: Enzyme replacement therapy is available for mucopolysaccharidoses type I (Hurler-Scheie and Scheie phenotypes), type II (Hunter syndrome), and type VI (Maroteaux-Lamy syndrome). Although enzyme replacement therapy may have systemic benefits for the patient, little evidence suggests that it favorably alters the natural history of the spinal disease.
• Bisphosphonate treatment: The bisphosphonates are a group of drugs that can reduce the bone resorptive effect of osteoclasts. They are used to increase bone density and reduce fracture rates in osteogenesis imperfecta. There is little data to suggest that they reduce the rate of progression of basilar invagination.