[Effectiveness of tunnel osteogenesis technique in treatment of aseptic non-hypertrophic nonunion of femoral shaft].

Objective: To investigate the effectiveness of tunnel osteogenesis technique combined with locking plate in the treatment of aseptic non-hypertrophic nonunion of femoral shaft.

Methods: The clinical data of 23 cases of aseptic non-hypertrophic nonunion of femoral shaft treated with tunnel osteogenesis technique combined with locking plate between January 2017 and December 2020 were retrospectively analysed. There were 17 males and 6 females with an average age of 41.4 years (range, 22-72 years). There were 22 cases of closed fracture and 1 case of open fracture. The types of internal fixation at admission included intramedullary nail in 14 cases and steel plate in 9 cases. The number of nonunion operations received in the past was 0 to 1; the duration of nonunion was 6-60 months, with an average of 20.1 months. Among them, there were 17 cases of aseptic atrophic nonunion of the femoral shaft and 6 cases of dystrophic nonunion. Twenty-two cases were fixed with 90° double plates and 1 case with lateral single plate. The operation time, theoretical blood loss, hospitalization stay, nonunion healing, and postoperative complications were recorded. Harris hip function score, Lysholm knee function score, lower extremity function scale (LEFS), and short-form 36 health survey scale (SF-36) were used at last follow-up to evaluate hip and knee functions. Visual analogue scale (VAS) score was used to evaluate the relief of pain at 1 day after operation and at last follow-up.

Results: The average operation time was 190.4 minutes, the average theoretical blood loss was 1 458.4 mL, and the average hospitalization stay was 8.2 days. All the 23 patients were followed up 9-26 months, with an average of 18.2 months. The healing time of nonunion in 22 patients was 3-12 months, with an average of 5.6 months. There were 8 cases of limb pain, 8 cases of claudication, 6 cases of limitation of knee joint movement, and 2 cases of limitation of hip joint movement. At last follow-up, the imaging of 1 patient showed that the nonunion did not heal, accompanied by pain of the affected limb, lameness, and limitation of knee joint movement. At 1 day after operation, the VAS score of 23 patients was 6.5±1.8, the pain degree was good in 7 cases, moderate in 12 cases, and poor in 4 cases; at last follow-up, the VAS score was 0.9±1.3, the pain degree was excellent in 21 cases and good in 2 cases, which were significantly better than those at 1 day after operation ( =12.234, <0.001; =-5.802, <0.001). At last follow-up, the average Harris hip function score of 22 patients with nonunion healing was 94.8, and the good rate was 100%; Lysholm knee function score averaged 94.0, and the excellent and good rate was 90.9%; LEFS score averaged 74.6; SF-36 physical functioning score averaged 85.0 and the mental health score averaged 83.6.

Conclusion: Tunnel osteogenesis technique combined with locking plate in the treatment of aseptic non-hypertrophic nonunion of femoral shaft has a high healing rate and fewer complications, which can effectively relieve pain and improve lower limb function and quality of patients' life.