Surgical management of a lumbar far lateral intervertebral disc extrusion in a cat.

Case summary: A 9-year-old male castrated domestic shorthair cat was presented with a 2-week history of acute, progressive left pelvic limb lameness. Gait evaluation revealed a grade 3/5 left pelvic limb lameness with no apparent orthopedic cause for the lameness based on orthopedic examination or radiographs. The neurological examination was otherwise normal. MRI revealed a left-sided L6-7 far lateral intervertebral disc extrusion with possible secondary neuritis of the L6 spinal nerve. A left-sided L6-7 foraminotomy was performed to remove the extruded disc material and provide additional space for the significantly enlarged nerve root. An L6-7 fenestration was also performed. The patient made an excellent recovery with near-complete resolution of lameness at 26 days postoperatively. Relevance and novel information: This case report contributes to the growing body of literature on lateral intervertebral disc extrusion as an etiological factor in pelvic limb lameness in cats, particularly when neurological deficits are absent. Furthermore, the case report highlights the diagnostic utility of cross-sectional advanced imaging for cats with lameness for which an orthopedic or radiographic cause cannot be identified. Finally, this case underscores the efficacy of surgical intervention as a treatment option for cats with lumbar far lateral intervertebral disc extrusions that do not improve with medical management alone. This finding could have implications for future surgical approaches in cats with similar findings.