gms | German Medical Science

Objective: Peroneal nerve injuries and their treatment are considered to be associated with bad clinical outcome. This study aims to analyze suspected risk factors which may influence the clinical outcome after surgical treatment of traumatic peroneal nerve lesions.

Methods: We conducted a retrospective analysis of patients with traumatic peroneal nerve injury treated by decompression, split repair or nerve grafting between 2010 and 2020. By using the motor function grading scale of the British Medical Research Council (MRC) pre- and postoperatively, the motor function of the peroneal nerve was evaluated and additionally, sensory deficits and pain within the innervation zone, as well as assumed risk factors favoring bad outcome were assessed. The follow up intervals were set at up to 6-month, 1-year and 2-years after surgery.

Results: In total, 93 patients were included in the present study work, 42 (45,16%) received decompression, 15 (16,13%) were treated by split repair and 36 (38,71%) needed autologous nerve grafting. The median time between trauma and nerve repair at our department were 4 months. The median muscle strength before surgery were M0 at all muscles innervated by the peroneal nerve, focusing on the anterior tibial muscle (ATM). Up to 1 year after surgery weakness of the ATM improved to the median of M3. After nerve decompression an improvement of 2 grades was found in 24 cases (57,14%) and 3 grades in 17 cases (40,48%), after split repair improvement of 1 grade was noted in 5 cases (33,33%) and 2 grades in 3 cases (20%), after nerve grafting we found improvement of 1 grade in 13 cases (36,11%) and 2 grades in 5 cases (13,89%). Patients with sensory disturbances improved in 47,27% 1 year after surgery. Pain relief was achieved in 7 cases (41,18%). We found no significant association between age, BMI, diabetes mellitus, and arterial hypertension and the postoperative outcome. The defect > 6cm was significantly more often associated with worse ATM improvement (p=0.04, OR 5.6).

Conclusion: According to the present data, a high number of patients achieved functional improvement after surgical treatment of traumatic peroneal nerve lesion. Even after peroneal reconstruction surgery more than 36% improved after 12 months, so that this procedure should be considered as an important treatment step in selected cases. Further studies are needed to identify potential risk factors in more details.