[Reconstruction of Lower Extremity Palsy after Pelvic Fractures with the Muscle Transfers]

PURPOSE OF THE STUDY The prevalence of nerve structure injuries accompanying pelvic and acetabular fractures is stated to be 5-25 %, with most frequent injuries to motor nerve structures associated with fractures of the posterior wall of the acetabulum. Prognostically worse outcomes of regeneration are documented mainly in iatrogenic, intraoperative injuries to nerve structures. This study aims to document the functional effect of muscle transfers restoring the movement of lower extremities with irreversible nerve lesion caused by the pelvic and acetabular fracture. MATERIAL AND METHODS A total of 18 patients with irreversible palsy of lower extremities in L4-S1 segments underwent a reconstruction surgery in the period 2006-2016, of whom 13 patients with the mean age of 42 (21-79) years arrived for a follow-up. The group included 10 patients with the loss of function of peroneal portion of the sciatic nerve, one patient sustained femoral nerve lesion and two patients suffered complete sciatic nerve lesion (both the peroneal and tibial portion). The patients were evaluated at the average follow-up of 77 (24-129) months after the reconstruction surgery. The average time interval from pelvic fracture to reconstruction by muscle transfer was 47 (18-151) months. Due to a wide spectrum of functional damage, the patients were evaluated in terms of the overall effect of the reconstruction surgery on the activities of daily living using the LEFS (The Lower Extremity Functional Scale). The surgical techniques used transposition of tensor fascie latae for femoral nerve lesion, transposition of tibialis posteriormuscle for palsy of the peroneal division of the sciatic nerve and tenodesis of tibialis anterior tendon and peroneus longustendon for the palsy of the peroneal and tibial portion of sciatic nerve. RESULTS The effect of movement restoration on daily living evaluated using the LEFS achieved 65 points (53-79) which is 85% of the average value of LEFS in healthy population. The transposition of active muscles tibialis posterior and tensor fasciae latae resulted in all the patients in active movement restoration. A loss of correction of foot position following the performed tenodesis of the paralysed tibialis anterior muscle was observed in one patient, with no significant impact on function. No infection complication was reported in the group. In 78% of patients the intervention was performed as day surgery. DISCUSSION There is a better prognosis for restoration in incomplete nerve lesion than in complete lesions and also in the loss of sensation than in the loss of motor function. The mini-invasive stabilisation of pelvic ring according to literature does not increase the risk of nerve lesions, while on the other hand a higher incidence of femoral nerve damage by INFIX fixator is documented. The type of muscle transfer is selected based on the availability of active muscles suitable for transposition and also with respect to functional requirements of the patient. CONCLUSIONS Irreversible palsy of lower extremity after the pelvic fracture is easily manageable as to the restoration of function. Surgical interventions using the preserved active muscles to restore the lost movement should be a component part of comprehensive surgical care for patients who sustained a pelvic fracture and should be performed centrally at a centre availing of comprehensive expertise. Key words: nerve lesion, tendon transfer, acetabulum, pelvis, fracture.