OBJECTIVETo explore causes and strategies for postoperative bone nonunion after bone transport of lower limb bone of chronic osteomyelitis with bone defect.

METHODSFrom June 2012 to December 2015, clinical data of 38 patients with lower limb bone of chronic osteomyelitis with bone defect were retrospectively analyzed, including 23 males and 15 females aged from 20 to 56 years old with an average of 36.5 years old; 5 cases occurred on 5 femoral osteomyelitis and 33 cases were tibial;the time from injury to bone transport ranged from 2 to 19 months with an average of 7.4 months; the distance of bone defect ranged from 4 to 12 cm with an average of 7.3 cm. Bone transport were performed at 1 week later after operations, and transport directions were from near-end to far-end for 30 cases, from far-end to near-end for 3 cases and bidirectional transport for another 5 cases. The alignment and transport speed were adjusted and weight-bearing was encouraged. Regular follow-up was performed and X-ray films were taken to observe complications such as poor mineralization in transport gaps, nonunion of docking sites, and recurrent fracture. Paley scoring was used to evaluate clinical effects.

RESULTSAll patients were followed up for 12 to 36 months with an average of 23.1 months. No recurrence of osteomyelitis, but multiple complications associated with poor bony healing occurred. In the process of bone transport, 3 cases occurred poor mineralization in transport gaps, 17 cases occurred ununion of docking sites, 5 cases suffered fracture gap, 1 case occurred fracture without remove of external fixation, and 4 cases occurred facture after remove of external fixation. The time of taken fixation ranged from 9 to 27 months with an average of 16.3 months; index of external fixation ranged from 1.7 to 2.7 months/cm with an average of 2.24 months/cm. According to Paley's scoring, bony results showed 12 cases excellent, 16 good, 3 moderate and 7 poor;and functional results showed 14 cases excellent, 18 good, 3 moderate and 3 poor.

CONCLUSIONSBone transport technique could effectively solve clinical problems of long bone osteomyelitis with bone defect. However, long treatment period influence prognosis. Therefore, indications should be chosen strict, and operations should be precise and accurate, also monitored across whole process and followed up in time. Doctors should be actively guide corresponding prevention strategies.