Tibia Malunion with Angular Deformity: Corrective Osteotomy and Intramedullary Fixation with the Chipping Technique

Abstract

Mr NH is a 31-year old man who presented to us with a nine-year history of deformity of his right leg. He was involved in a road traffic accident in 2008 where he sustained an open fracture of his right tibia which was complicated with compartment syndrome. He underwent fasciotomy and external fixation of his right tibia. The fasciotomy wound later was closed by split skin grafting. Later the external fixator was removed and converted to plaster of Paris. However he then didn't turn up for follow up. Other than his bended leg, he claims that he was able to continue his work as a labourer with no limitation in his work and daily activity. He denied any history of fever, pain or sinus discharge from the leg. On examination, there was healed fasciotomy scar of the right leg on the medial and lateral surfaces of the leg with wasting of the calf muscle. There was also equinus deformity of the right ankle and clawed toes. This is evident by the formation of callosity along the metatarsal head at the plantar aspect. There was also a clinically malunited fractures of the midshaft right tibia and fibula with an anterior angulation of the leg measuring 40 degrees on the goniometer. There was a limb length discrepancy of 0.5cm on the right relative to the left. He had no distal neurovascular deficit (Figure 1A & 1B). The range of motion of his right knee was full. However there was limitation of dorsiflexion on his right ankle at 0 degree, while plantar flexion is full. Despite all this, his gait is normal and he is able to fully squat normally. Antero-posterior and lateral radiographs of the leg showed malunited fractures of the midshaft of the right tibia and fibula with anterior angulation (Figure 2A & 2B). Abstract There are few options for correcting severe malunion of tibial shaft. Acute correction by close wedge osteotomy followed by fixation with plate is a standard treatment for this but associated with shortening and non-union. Gradual correction with circular external fixation is able to correct the deformity without producing shortening. However it is uncomfortable and require tedious nursing and rehabilitative care. Chipping the non-union site was associated with a favorable outcome for femur fracture because it biologically enhances fracture healing. However, there is no report on chipping osteotomy for tibia mal-union. We consider chipping osteotomy as a treatment option for this patient who refuses to have external fixation for his treatment. Patient achieved corrected alignment of tibia and fracture union in 5 months. However he develops problem with wound healing of the wound.