Our Approach to Intervertebral Disc Disease in Dogs: A Review of the Current Literature
Nikola Heblinski and Hugo Schmökel
Journal of Veterinary Science and Medical Diagnosis ( J Vet Sci Med Diagn 2018, 7:1)
This page presents a summary of the key information presented in the above paper which will be of most relevance to Dachshund owners. The references are not included in these notes; refer to the full paper for details.
Common forms of Intervertebral Disc Extrusion
Dachshunds typically suffer from Hansen Type 1 IVDE. There are 6 common sub-types:
DEEH = Disc extrusion with extensive hemorrhage
ANNPE = Acute non-compressive nucleus pulposa extrusion
IIVDE = Intradural/intramedullary vertebral disc extrusion
HNPE = Hydrated nucleus pulposa extrusion
Prognosis of dogs with IVDE
Successful surgical outcomes are seen in 86-96% of non-ambulatory dogs with intact Deep Pain Perception (DPP).
A positive indicator for fast recovery is some motor function after surgery. Reported time to ambulation is around 7-14 days (in up to 96% of cases) although this will be longer in dogs with severe signs prior to surgery. Time to establish bladder control after surgery is typically shorter than time to regain ambulation and is correlated with severity of pre-operative signs.
Disc extrusions with extreme hemorrhage (DEEH) seem to have a lower healing rate.
Loss of Deep Pain Perception (DPP) is considered to be the only clinical sign which negatively affects prognosis with surgical success rates ranging from 0-76% and averaging 50%. Most studies show that surgery is more successful when performed within 24 hours of loss of DPP. However, it is often not possible to identify precisely when DPP was lost. MRI scans and the presence or absence of a hyperintense intramedullary signal in T2 weighted scans have been shown to be strongly correlated with surgery outcomes. MRI is therefore recommended to make a more exact prognosis in dogs with severe symptoms.
The Frankel Scoring system is the reverse of the clinical grading system often quoted in the UK (where Grade 1 is a low grade incident and Grade 5 is a severe case).
Conservative treatment of IVDE
There is a lack of scientific evidence from prospective controlled studies into conservative treatment. However, the published evidence suggests 82-100% of ambulatory dogs (Frankel 4 & 5) were treated successfully with a conservative approach compared with 23-55% of non-ambulatory dogs (Frankel 0-3). Success of conservative treatment in Frankel 0 cases is close to zero.
Relapse rates with conservative treatment of Frankel 3 cases were 30-50%. The high rate of relapse in these cases may be considered an argument for surgery.
Surgical treatment of IVDE
Surgical treatment of IVDE is recommended for spinal pain or paresis unresponsive to conservative treatment, but also for patients with recurrence of clinical signs during or after conservative treatment. Non-ambulatory patients are generally candidates for immediate imaging and decompressive surgery, with the aim of removing all extruded Nucleus Pulposa material.
Robust evidence shows that surgery is recommended in dogs with Frankel scores of 0, 1 or 2.
The sooner a dog can move its affected legs and empty the bladder, the lower the post-surgery complication rate.
Recurrence rate of IVDE after surgery
Reherniation can occur at the same site up to 4 weeks after surgery. Further imaging is recommended if there is unexpected pain or neurological deterioration in the immediate period after surgery. Most cases can be re-operated with a successful outcome. Recurrence rates range from 5-15% with the subsequent herniation occurring at a different site in 83-100% of cases. There is evidence that recurrence rates are higher in cases where prophylactic fenestration had not been done.