Multiple thoracolumbar partial lateral corpectomies in 17 dogs

To report feasibility and outcome of multiple thoracolumbar partial lateral corpectomies (TLPLCs) in dogs with predominantly ventral spinal cord compression caused by intervertebral disc disease (IVDD) in the light of reported decreased spinal stability following single TLPLC. Material und methods: In a retrospective study the records of dogs treated by multiple TLPLCs for ventral spinal cord compression caused by Hansen type I or type II IVDD were reviewed. Presurgical spinal cord compression and postsurgical decompression, as well as slot dimensions were determined based on computed tomography (CT)-myelography images. Neurological outcome was assessed based on repetitive examinations applying a modified Frankel Score as well as on an owner questionnaire.

Seventeen dogs with a mean body weight of 20.3 kg (range 4.0-49.0 kg) were included. Fourteen dogs had two TLPLCs, two dogs had three TLPLCs and one dog had four TLPLCs performed. The mean slot depth was 63% of entire vertebral body width, the mean slot height was 29% of the entire vertebral body height, the mean slot length was 25% of the entire vertebral body length and the mean residual vertebral interslot length between two adjacent TLPLCs was 55% of the vertebral body length. At reevaluation 4 weeks after surgery, 6/17 dogs (35.3%) had the same modified Frankel Score as before surgery, whereas 11/17 dogs (64.7%) showed a neurological improvement. According to the owners 78.5% of dogs were walking normally within 6 months after surgery. The mean survival time of 16 dogs, where follow-up was available, was 951 days.

Multiple spinal cord compressions caused by IVDD can be eliminated by multiple, even consecutive, TLPLCs without the risk of a clinically significant risk of spinal instability.