Abstract
This study addresses the evolution of the orthopaedic management of patients with hypophosphatemic rickets, with the aim of providing skeletal mature aligned lower limbs, with minimal surgical insult.
Methods
We describe a case series of 8 patients with hypophosphatemic rickets that highlight an evolution in practice over the last 8 years. Our initial treatment involved external fixation with circular frames, addressing both axial deformity and length. Two contralateral long bones were addressed simultaneously and surgery was conducted in early adolescence. Problems encountered were poor quality regenerate, requiring prolonged periods in external fixation, and often recurrence of deformity following frame removal. Minor deformity recurrence made planning for the often inevitable knee replacement difficulty. Our current management is that patients only start surgical correction once skeletal maturity has been reached, two contralateral axial long bone corrections are performed using CHAOS (computer hexapod-assisted orthopaedic surgery) procedures with IM nails and multiple osteotomies (occasionally locking plates are required). Patients are able to fully weight bear immediately post operatively, after a suitable recovery period the remaining bones can be corrected. Then lengthening can be considered once the osteotomies have fully consolidated by exchange nailing of the femur, for an IM lengthening nail. At this stage the patient is able to fully consider the risks and benefits of this final and potentially unnecessary procedure.
Conclusions
Hypophosphotaemic rickets is a rare condition, both the disease and its management can have severe effects on patients both physically and psychologically, at Bristol we have developed an treatment pathway that we feel helps to minimize the physical and psychological effects of treatment, with the end result of aligned lower limbs, that should provide a good basis for arthroplasty surgery if required in adulthood.
