Practice patterns in the management of acute intervertebral disc herniation in dogs.

OBJECTIVES: Acute intervertebral disc herniation is commonly managed by veterinary neurologists and surgeons. Anecdote suggests that patterns of management vary considerably and there is controversy surrounding many aspects of treatment. The goal of this study was to document patterns in management of acute spinal cord injury caused by acute intervertebral disc herniation among these two groups to aid in future discussions on best practices. METHODS: A survey querying diagnostic, medical and surgical practices for dogs with acute intervertebral disc herniation was distributed to diplomates on the databases of the American College of Veterinary Surgeons and the American College of Veterinary Internal Medicine (Neurology). RESULTS: Responses were received from 314 board-certified veterinary surgeons and neurologists. Both groups handled timing of decompression, surgical approach, and most postoperative recommendations in a similar fashion. Case volume differed between groups, with 77% of neurologists and 18% of surgeons managing ê50 cases of acute intervertebral disc herniation per year. MRI was used most frequently as a diagnostic tool by neurologists (75%), while CT was used most commonly by surgeons (58%). Corticosteroids were routinely administered as a neuroprotective strategy by 34% of surgeons and 11% of neurologists. Disc fenestration was performed "always" or "most of the time" by 69% of neurologists and 36% of surgeons. CLINICAL IMPORTANCE: Understanding the common practices in the management of canine acute intervertebral disc herniation can provide a springboard for future discussions regarding the best practices in diagnosing and treating this disease.

Minimally invasive approach to lumbosacral decompression in a cadaveric canine model.

AIMS: To determine efficacy of a minimally invasive (MI) surgical approach using a human MI lumbar retractor for canine lumbosacral dorsal laminectomy and partial discectomy and to compare this technique to the standard open surgical (OS) approach. METHODS: Lumbosacral dorsal laminectomy and partial discectomy was performed on 16 large-breed canine cadavers using either a standard OS (n=8) or MI (n=8) approach. Skin and fascial incision length, procedure time, and intraoperative complications were recorded. Postoperatively specimens were evaluated for laminectomy and discectomy dimensions, and visible damage to the cauda equina and exiting nerve roots. RESULTS: Median length of skin and fascial incisions in the OS group were longer than in the MI group (p<0.001). Median laminectomy length was similar between both approaches (p=0.234) but width was greater for the MI than OS approach (p=0.002). Both approaches achieved similar partial discectomy width (p=0.279). Overall surgical time was longer for MI approaches compared to OS, with a median of 18.5 (min 15.5, max 21.8) minutes for MI compared to 14.6 (min 13.1, max 16.9) minutes for OS (p=0.001). CONCLUSIONS: The MI approach reduced incision lengths while retaining comparable laminectomy and discectomy dimensions. For this in vitro model the MI approach required more time to complete, but this difference may not be relevant in clinical cases. CLINICAL RELEVANCE: Dogs undergoing lumbosacral dorsal laminectomy are commonly large-breed dogs. The traditional open approach requires a large skin incision and soft tissue dissection, especially in overweight animals. A MI approach accomplishing the same surgical result while minimising soft tissue trauma could reduce post-operative pain and recovery time, and may lower wound-related complications. Clinical studies are needed to confirm postoperative benefit and assess operating times in vivo.

The use of an electronic von Frey device for evaluation of sensory threshold in neurologically normal dogs and those with acute spinal cord injury.

The utility and inter-session repeatability of sensory threshold measurements using an electronic von Frey anesthesiometer (VFA) were assessed in a group of six neurologically normal dogs. Sensory threshold values obtained in neurologically normal dogs were compared to those of dogs with acute spinal cord injury (SCI) caused by intervertebral disc extrusion (n=6) and to a group of neurologically normal dogs with cranial cruciate ligament rupture (CCLR; n=6). Sensory threshold values in neurologically normal dogs were 155.8 ± 37.7 g and 154.7 ± 67.2 g for the left and right pelvic limbs, respectively. The difference in mean sensory threshold values obtained for the group when two distinct testing sessions were compared was not statistically significant (P>0.05). Mean sensory threshold values for the group with SCI were significantly higher than those for neurologically normal dogs at 351.1 ± 116.5 g and 420.3 ± 157.7 g for the left and right pelvic limbs, respectively (P=0.01). A comparison of sensory threshold values for the group with CCLR and neurologically normal dogs was not statistically significant (P>0.05). The modified dorsal technique for VFA described here represents a reliable method to assess sensory threshold in neurologically normal dogs and in those with SCI.