Hexaxial external fixator versus intramedullary nail in treating segmental tibial fractures: a retrospective study

Background It's difficult to treat segmental tibial fractures (STFs), which are intricate injuries associated with significant soft tissue damage. The aim of this study was to compare the clinical effect of hexaxial external fixator (HEF) and intramedullary nail (IMN) in treatment of STFs. Methods A total of 42 patients with STFs were finally recruited between January 2018 and June 2022. There were 25 males and 17 females with age range of 20 to 60 years. All fractures were classified as type 42C2 using the Arbeitsgemeinschaftf & uuml;r Osteosythese/Orthopaedic Trauma Association (AO/OTA) classification. 22 patients were treated with HEF and 20 patients were treated with IMN. The condition of vascular and neural injuries, time of full weight bearing, bone union time and infection rate were documented and analyzed between the two groups. The mechanical medial proximal tibial angle (mMPTA), mechanical posterior proximal tibial angle (mPPTA), mechanical lateral distal tibial angle (mLDTA), mechanical anterior distal tibial angle (mADTA), hospital for special surgery (HSS) knee joint score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle joint score, range of motion (ROM) of flexion of keen joint and ROM of plantar flexion and dorsal flexion of ankle joint were compared between the two groups at the last clinical visit. Results There were no vascular and neural injuries or other severe complications in both groups. All 22 patients in HEF group underwent closed reduction but 3 patients in IMN group were treated by open reduction. The time of full weight bearing was (11.3 +/- 3.2) days in HEF group and (67.8 +/- 5.8) days in IMN group(P< 0.05), with bone union time for (6.9 +/- 0.8) months and (7.7 +/- 1.4) months, respectively(P< 0.05). There was no deep infection in both groups. In the HEF group and IMN group, mMPTA was (86.9 +/- 1.5)degrees and (89.7 +/- 1.8)degrees(P< 0.05), mPPTA was (80.8 +/- 1.9)degrees and (78.6 +/- 2.0)degrees(P< 0.05), mLDTA was (88.5 +/- 1.7)degrees and (90.3 +/- 1.7)degrees(P< 0.05), while mADTA was (80.8 +/- 1.5)degrees and (78.4 +/- 1.3)degrees(P< 0.05). No significant differences were found between the two groups at the last clinical visit concerning HSS knee joint score and AOFAS ankle joint score, ROM of flexion of keen joint and ROM of plantar flexion of ankle joint (P> 0.05). The ROM of dorsal flexion of ankle joint in IMN group was (30.4 +/- 3.5)degrees, better than (21.6 +/- 2.8)degrees in HEF group (P < 0.05). Conclusion In terms of final clinical outcomes, the use of either HEF or IMN for STFs can achieve good therapeutic effects. While HEF is superior to IMN in terms of completely closed reduction, early full weight bearing, early bone union and alignment. Nevertheless, HEF has a greater impact on the ROM of dorsal flexion of the ankle joint, and much more care and adjustment are needed for the patients than IMN.