Epineural Neurorrhaphy of a Large Nerve Defect Due to IatroGenic Sciatic Nerve Injury in a Maltese Dog

Abstract

Epineural neurorrhaphy is a standard nerve repair method, but it is rarely reported in veterinary literature. Epineural neurorrhaphy in canine sciatic nerve injury are described in this report. An 11-month-old, castrated male Maltese dog, presented with an one-month history of non-weight bearing lameness and knuckling of the right pelvic limb. The dog showed absence of superficial and deep pain perception on the dorsal and lateral surfaces below the stifle joint. The dog had undergone femoral head and neck osteotomy in the right pelvic limb one month prior to referral at a local hospital. Based on physical and neurological examinations, peripheral nerve injury of the right pelvic limb was suspected. Radiography showed irregular bony proliferation around the excised femoral neck. Magnetic resonance imaging revealed sciatic nerve injury with inconspicuous continuity at the greater trochanter level. A sciatic nerve neurotmesis was suspected and surgical repair was decided. During surgery, non-viable tissue of the sciatic nerve was debrided, and epineural neurorrhaphy was performed to bridge a large, 20-mm defect. The superficial and deep pain perception was progressively improved and restored at 3 weeks postoperatively, and the dog exhibited a gradual improvement in motor function. At 10 weeks postoperatively, the dog showed no neurological deficit including knuckling but the tarsal joint hyperextension did not improve due to ankylosis. The dog had undergone tarsal arthrodesis and exhibited almost normal limb function without any neurologic sequela until the last follow-up at 2.5 years postoperatively.

Traumatic and iatrogenic sciatic nerve injury in 38 dogs and 10 cats: Clinical and electrodiagnostic findings

“…Surgical intervention for traumatic SNI has been widely described, but decision-making remains to be tailored to the individual patient according to clinical, imaging, and EDX results. [47][48][49][50][51] With or without surgical intervention, physiotherapy and the use of tarsus-foot orthosis might be suggested as soon as possible in veterinary patients regardless of predicted outcome. [52][53][54] Indeed, physiotherapy would help maintain muscle tone and avoid fibrosis, whereas the use of orthosis could stabilize the hock joint and prevent cutaneous lesions arising from dragging the hindlimb.…”

“…Unfortunately, CMAP amplitudes <1.45 mV showed poor ability to predict negative outcome. Surgical intervention for traumatic SNI has been widely described, but decision‐making remains to be tailored to the individual patient according to clinical, imaging, and EDX results 47‐51 . With or without surgical intervention, physiotherapy and the use of tarsus‐foot orthosis might be suggested as soon as possible in veterinary patients regardless of predicted outcome 52‐54 .…”