Does weight-bearing assignment after intramedullary nail placement alter healing of tibial shaft fractures?

Abstract Introduction There is no consensus regarding postoperative weight-bearing (WB) assignment after treatment of tibial shaft fractures with an intramedullary nail. This study aims to determine if the postoperative WB assignment after tibia intramedullary nail placement alters healing. Methods Closed AO type 42A fractures treated with a reamed statically-locked intramedullary nail over a 10-year period were retrospectively reviewed from injury at 2, 3, 6, 9 and 12 month intervals until union or revision. Patients were categorized according to postoperative weight-bearing assignment: weight-bearing-as-tolerated (WBAT) or non-weight-bearing (NWB). Patients with additional diagnoses that confound routine fracture healing were excluded. Postoperative radiographic union scores for tibial fractures (RUST), coronal/sagittal angulations, and length were compared between different weight-bearing groups. Union was defined as a RUST ≥ 10 at a painless fracture site. Results A total of 83 patients achieved union (32 WBAT, 51 NWB). Both WB groups had similar preoperative demographics. Average age was 37 ± 13 years and follow-up averaged 1.3 ± 0.2 years. There were no significant differences in average time to radiographic union between NWB versus WBAT groups (5.5 vs. 6.1 months, respectively; P  = 0.208) nor radiographic healing at 2, 3, and 6-month intervals ( P  = 0.631). There were two nonunions and one fracture shortened in the NWB group. There were no reoperations for symptomatic or broken hardware in either cohort. Conclusion Immediate WBAT after statically-locked intramedullary nail placement in simple tibial shaft fractures does not alter the time until or course of radiographic union. Level of evidence IV.