A rare case of pycnodysostosis: Technical difficulties in managing long bone fractures

Pycnodysostosis is a rare inherited disorder of autosomal recessive trait causing cathepsin K deficiency, leading to failure of osteoclastic activity. Brittle and sclerotic bones which are prone for frequent fractures is the characteristic feature of this congenital disorder. Despite good healing potential there are few issues in the management of fractures in pycnodysostosis patients. In this article we report the challenges faced in managing a fracture of the femoral shaft in a 12 year old girl with pycnodysostosis. For early rehabilitation and to avoid deformity and shortening, we opted for surgical fixation over conservative treatment. Narrow medullary canal ruled out the option for titanium elastic nail fixation. 4.5mm dynamic compression plate was used to fix the fracture. Sclerotic bone made drilling extremely difficult. Deformed femoral shaft allowed plating over the anterior surface only, instead of the routine lateral surface plating. Postoperative fracture healing was satisfactory. Implant was removed after 18 months.