Microsurgical Repair of severed thoracic spinal cord and clinical outcomeDear Editor,A fit and well 34-year-old man was admitted to the emergency service with multiple stab injuries to posterior thorax and occiput with a retained knife in his interscapular area. He remained haemodynamically stable and neurological examination revealed normal power in upper limbs and a 4/5 power in his right lower limb, 0/5 power in his left lower limb. Sensory examination revealed an intact pin prick and light touch from C2-T4, altered sensation T5, absent sensation to pin prick and light touch from T6-S2 with intact perianal sensation. He had a Motor incomplete- ASIA impairment score (AIS) D score. A CT spine was confirmed trajectory of the knife traversing the superior T2 right lamina into left inferior posterior T2 vertebral body ( Figure:1a,b,c ). There was no associated vascular injury associated.A thoracic T2 and T3 laminectomy and removal of foreign body was performed within 3 hours post presentation. The knife was noted to be retained in the right paraspinal region with a trajectory of the knife tip to the midline. A 10 cms midline incision made and connecting the oblique right paraspinal wound. The paraspinal muscles dissected and laminae of T2/3 expose and T2/3 laminectomy completed with high speed drill.
Under microscopic guidance, the knife was removed with minimal manipulation. The tip of the knife penetrated the right side of the cord causing about 60% of the cord severed and the dura appeared contused and severed (Figure:2a). At this stage, 8 mgs dexamethasone was administered intravenously. The torn right hemi cord was sutured with continuous 7’0 prolene (Figure:1d). Haemostasis secured with Floseal®. Dural margins were trimmed and a watertight duroplasty was performed Duraguard TM with 3’0 prolene. Tisseel glue was used to seal the duroplasty margins. Wound closed in layers. No post-operative surgical complications were encountered.He was treated in the intensive care unit and was noted to have complete loss of power in both legs for 8 days and a power of 1/5 noted in his left extensor hallucis longus that improved to 4/5 over 6 weeks. Sensory examination revealed a Brown-Séquard syndrome pattern with loss of pinprick sensation and temperature below T4 on the right side which recovered on the left side. Post-operative spinal MRI at day 4 revealed high signal at the repair sight at the T2/3 level . At a 3 month follow-up his is mobilising independently with normal lower limb power and needs crutches for maintaining truncal balance.Stab wounds of the spinal cord represent approximately 26% of all spinal cord injuries1-3and remains the most common cause of traumatic Brown-Séquard syndrome 5-7. In this case, the patient had a picture of post traumatic Brown-Séquard syndrome like picture with complete recovery of the motor functions in a 3 month period with persistent sensory on the right side. Approximately 42% of patients with SCI have complete dysfunction without any movement or sensation below the site of injury. Interestingly, only 14.3% of all SCIs are believed to be anatomically complete injuries, while the remainder of SCIs are considered as an incomplete functional deficiency with a few spared connections that could be established under proper interventions 4,8. An MRI performed at 3 months revealed sign of significant spinal cord injury in the and microhaemorrhages in the cord above and below the level of injury with associated post-operative changes ( Figure 1e,f). His ASIA score improved to E from D.To date, SCI is considered extremely difficult to treat. Therapeutic options include surgical decompression, anti-inflammatory drugs, hyperbaric oxygen therapy, and rehabilitation interventions10. Despite the intensive rehabilitation programs carried out in hospitals worldwide, SCI is still associated with a high disability rate 8-10.The clinical outcomes of SCI depend on the severity and location of the lesion and may include partial or complete loss of sensory and/or motor function below the level of injury. SCI typically affects the cervical level of the spinal cord (50%) with the single most common level affected being C5 2,8. Other injuries include the thoracic level (35%) and lumbar region (11%). With recent advancements in medical procedures and patient care, SCI patients often survive these traumatic injuries and live for decades after the initial injury4,10.In this case, the patient had signs and symptoms of Incomplete cord injury/ Brown-Sequard syndrome that was successfully managed with timely surgical intervention, intense post-operative care and physiotherapy. There is a paucity of reports eluding to repair of the spinal cord secondary to stab injury and particularly to the thoracic spine. Spinal cord repair is technically feasible considering several factors into consideration particularly the nature of the foreign body and in this particular case, knife injury had caused a horizontal cordotomy. Microsurgical technique was used in a standard fashion which proved to be beneficial in this case. This is the first documented case of hemi-section of the thoracic cord secondary to stab injury that was successfully repaired and the patient has made a successful functional recovery. Timely surgical intervention and meticulous microsurgical repair of severed spinal cord with intense post-operative care and rehabilitation may prove beneficial for good functional and neurological recovery.
