[Evaluation of lower limb function and gait characteristics after fibulectomy in adults].

Objective: To explore the effects of fibulectomy on lower limb function and gait of adult patients through gait analysis, in order to provide guidance for clinical treatment.

Methods: A clinical data of 24 patients who underwent fibulectomy and met the selection criteria between January 2017 and December 2022 was retrospectively analyzed. There were 12 males and 12 females with an average age of 25 years (range, 18-68 years). The length of fibulectomy was 10-19 cm, with an average of 15 cm. The patients underwent routine rehabilitation training after operation. The occurrence of postoperative complications was recorded, the pain degree of surgical incision was evaluated by visual analogue scale (VAS) score, and the residual fibular bone was reviewed by imaging. A gait test system was used before operation and at 6 months after operation to collect gait data of healthy and affected sides under slow, medium, and fast velocity conditions, including gait parameters (foot rotation angle, step length, support phase, swing phase, gait line length, single support line, maximum force 1, maximum force 2) and the tripod area parameters (maximum pressure, time maximum force, and contact time of forefoot, midfoot, and hindfoot).

Results: All incisions healed by first intention after operation. All patients were followed up 1-5 years, with an average of 3 years. The great dorso-extension muscle strength decreased in 3 cases, and the sensory defects in the operative area and distal part occurred in 5 cases. The VAS scores of incisions were 0-6 (mean, 4) at 6 months after operation and 0-5 (mean, 2) at last follow-up. During follow-up, imaging review showed that 5 cases had osteoporotic changes of distal residual bone of the fibula, and the residual segment was shorter and more significant; 3 cases had new bone formation. The results of gait test showed that the gait parameters and the tripod area parameters under the three gait speeds were consistent. There was no significant difference in the gait parameters and the tripod area parameters between the healthy side and the affected side before operation ( >0.05). Compared with the healthy side, the foot rotation angle, the single support line, the maximum force 1, the maximum force 2, and the maximum pressures of the forefoot and midfoot of the affected side significantly decreased after operation ( <0.05), and the step length, the time maximum force of midfoot and hindfoot, and the contact time of the forefoot and midfoot significantly increased ( <0.05). Compared with preoperative conditions on the same side, the foot rotation angle, the gait line length of both sides significantly decreased ( <0.05), and the maximum pressures of the forefoot, midfoot, and hindfoot and the time maximum force of the midfoot significantly increased ( <0.05); the step length on healthy side significantly decreased, while the affected side significantly increased ( <0.05); the maximum force 1 and the maximum force 2 on the healthy side significantly increased, while the affected side significantly decreased ( <0.05); the single support line on the affected side significantly decreased ( <0.05).

Conclusion: Different degrees of clinical symptoms occurred, gait pattern changes, compensatory gait appears, gait stability decreases, and the risk of tumble increases in adult patients after partial fibulectomy. Therefore, it is recommended to walk slowly after fibulectomy.