Upper Limb Pathology in Children with Mucopolysaccharidoses

Background. Despite the success in the treatment of children with mucopolysaccharidoses (MPS) as a result of the widespread of enzyme replacement therapy and hematopoietic stem cells transplantation, orthopedic manifestations continue to be a significant problem, while the pathology of the upper limbs in children with MPS is not sufficiently represented in the literature. The aim of this studywas to analyze orthopedic and neurological manifestations in the upper extremities of children with mucopolysaccharidosis based on a sequential case series. Materials and Methods. We carried out a comprehensive analysis of clinical and radiological involvement of the upper extremities in 49 patients with MPS. Results. The most common complaints reated to the upper extremities were difficulties in the daily activities (dressing, self-care, playing), impairment of the fine motor skills, and muscle weakness. The most frequent clinical manifestations related to the upper extremities were limited active shoulder abduction, impaired hand grip, flexion contractures of the elbow joint, ulnar deviation of the hand. All patients with MPS types I, II, and VI had limited active and passive extension and flexion of the metacarpophalangeal and interphalangeal joints. In patients with MPS IV, hypermobility of the hand joints prevailed. We noticed minimal presence of typical clinical manifestations related to compression of the median nerve secific for carpal tunnel syndrome. The majority of patients showed a decrease in tendon and periosteal reflexes. The most pronounced decrease in muscle strength was observed in to extensors (elbow, fingers) and shoulder abductors, which may contribute to the predominant formation of a flexion pattern of contractures. On radiographs of the hand, the “melting sugar” symptom and shortening of the metacarpal bones were observed in most patients. Conclusion.Clinical and radiological manifestations related to the upper extremities take place in all types of the mPS, and lead to functional disorders that complicate daily life and self-care. Upper limb pathology in children with MPS requires earlier detection and more active treatment after comprehensive risk assessment.