The Surgical VS Conservative Debate… Gold Standard Care for Canine IVDD

INTRODUCTION

Canine intervertebral disc disease (IVDD) is the most common spinal disease found in the modern day dog. It is a degenerative condition, but certain breeds of dog are at increased risk. Chondrodysplasic dogs (CDPA) with a short-legged phenotype are most vulnerable, whilst dogs with the mutated chondrodystrophy gene (CDDY) are at even further risk of developing premature degeneration of inter-vertebral discs. Examples of short-legged breeds at risk of developing the CDDY gene include the Basset hound, Corgi, Dachshund, French bulldog and Shih tzu (UC Davis Veterinary Medicine, 2024). It is important to note that not every single dog amongst these breeds will develop canine IVDD, and whilst they are at greater risk of inheriting the genetic mutations required to cause the disease, all dog breeds can be at risk of developing a spinal injury.

To explain this a little further, IVDD affects the space between the bones (vertebra) in the spine. This space can cause herniation (bulging) of the soft, jelly-like inter-vertebral discs, which can result in pressure on the spinal cord itself. If this happens, then canine IVDD can present as limb weakness, incontinence and pain signals (such as shivering, panting, whimpering and hunched posture), all of which can eventually lead to paralysis if extreme neural compression occurs, so it is important to catch the signs and symptoms in their early stages to allow quick intervention. The gold standard diagnostic tool for IVDD is magnetic resonance imaging (MRI), with differentiations of the type of IVDD diagnosed described in the table below (Granger, 2024):

| Table: Types of canine IVDD (Granger, 2024) |

As with most pathologies, there is often a discussion surrounding the best protocol of care, which can be a challenging decision for clinicians to make when each case is so unique. As a veterinary physiotherapist, I am fortunately not required to make these decisions, but it is still important to have an understanding of what to look out for, when to refer and why a clinician may have come to their conclusion for treatment.

Therefore, I will be exploring the gold standard protocol of care for a dog with IVDD within this blog, whilst also asking- what are the different conservative and surgical options, and why and when are each indicated?

SURGICAL MANAGEMENT OF CANINE IVDD

Whether a veterinarian decides to operate on a dog depends entirely on the case at hand. For mild cases, conservative management on its own may be an option. However, Olby et al. (2022) have shown that amongst ambulatory dogs, surgical outcomes were 98.5% effective, whilst purely conservative management has 80% effectiveness. This outcome lowers as the case becomes more severe, with only a 61% surgical success rate for dogs who are paraplegic. This rather drastically drops to 21% when a purely conservative approach is taken, so surgery is more often than not advised for more severe non-ambulatory cases. The majority of the studies presented within this literature review uses a hemi-laminectomy approach to surgery.

Hemi-laminectomy is a surgical procedure which allows clinicians to operate on the spine. Once they can see the ruptured discs by removing the lamina or vertebral bone, the damaged areas can be removed to ease pressure on the spinal cord. Decompressive surgery like hemi-laminectomy is the most commonly performed surgery due to its high recovery rate. Olby et al. (2022) also discuss in depth the efficacy of fenestration surgery, which can either be carried out alongside decompression as a prophylactic procedure, or as a stand-alone operation. Fenestration is the removal of the nuclei polposus (the central portion of the inter-vertebral disc) through a small gap made in the annulus fibrosis. It has been reported amongst a range of studies that fenestration surgery as a prophylactic procedure alongside decompression results in the lowest rate of symptom reoccurrence, so is often recommended as the best course for surgical procedure following diagnosis (Olby et al., 2022).

| Table: Modified Frankel Score (MFS) (Based on the Frankel Score (Frankel, 1969)) |

When we consider the recovery rate of dogs post-surgical intervention for IVDD, there is research to suggest that early surgical intervention had a positive impact on post-operative success. Hermansen et al. (2022) studied the outcome of timing of surgery (unfortunately it is not specified what type of surgery was completed) on patient outcome, using the modified frankel score (MFS) as an outcome measure. They interestingly found that prompt surgical intervention positively affects the MFS, with all dogs having an improvement in their score at the 6 month period. These results would indeed then suggest that early surgical intervention does have a positive effect on neurological symptoms in dogs. A similar study by Necas (1999) looked at clinical outcome of hemi-laminectomy approach on 300 dogs- a much better clinical sample size than the study by Hermansen et al. (2022). They found that the results of surgical intervention within 48 hours of diagnosis in grade II dogs was excellent 80% of the time, a result which backs up the findings of both studies. It is important to note that it is not clear within this study what is defined as excellent, as no outcome measure has been reported within this study.

Moore et al. (2020) argue that the current research to support urgent intervention for IVDD in dogs is weak, and that the only indication for decompression within 24 hours of symptom onset is the increased risk of myelomalacia. Myelomalacia is considered to be a softening of the spinal cause, leading to complications such as loss of deep pain signals. To summarise, it appears that although each case is unique, the severity of the case can guide whether a veterinarian should perform surgery or not. For more severe cases, early intervention- often using a hemi-laminectomy approach- offers the best outcome long term to reduce the chance of developing post-operative complications such as myelomalacia.

CONSERVATIVE MANAGEMENT OF CANINE IVDD

During their study, Hermansen et al. (2022) report the use of massage, passive range of motion exercises and hydrotherapy as tools of conservative management following surgery. Would the surgical results have been so successful without the use of physiotherapy? It is difficult to know, as they did not complete a randomised control trial (RCT) comparing the benefit of surgery with or without post-operative physiotherapy. However, they do report an overall significant post-operative success, using a combination of both surgery and physiotherapy.

Research tends to report a “personalised patient pathway” for conservative management of IVDD in dogs. This is because each case will vary so much with the presentation of signs and symptoms, and rehab goals will vary between each dog and their normal level of function. Moore et al. (2020) discuss the timing of physiotherapy intervention, suggesting that whilst it can greatly improve function, timing must be right to prevent maladaptive neuroplasticity. Jeong et al. (2019) completed a retrospective study assessing the efficacy of surgery with and without physiotherapy, and there was a hugely significant difference between the intervention/no intervention groups, with 86.46% of dogs neurologically improving with physiotherapy, compared to 52.22% neurologically improving without physiotherapy.

Within this study, the types of physiotherapy utilised were electrotherapy, weightbearing and weightshifting training using stable and unstable surfaces, hydrotherapy and spinal reflex stimulation. This reflects a similar programme used by Zidan et al. (2018), who studied dogs with and without intervention over a 14 day period, and found that there was no significant difference between the two groups for return to full ambulation (walking). The rehabilitation programme included supported standing, neuromuscular electrical stimulation (NMES), weightshifting, balance board exercises and underwater treadmill. They have suggested that early rehabilitation is safe to utilise but does not necessarily offer significant benefit for return to ambulation following surgery compared to no rehabilitation intervention, which entirely contradicts the results of the Jeong et al. (2019) study. As argued by Moore et al. (2020), it is difficult to compare many of the IVDD rehabilitation studies despite conflicting results, as there is no standardised physiotherapy programme, and most dogs have huge variation in both breed type, and severity of injury. Amongst humans with spinal cord injury (SCI), the research is very “pro-rehabilitation”, and many veterinarians advocate for physiotherapy following diagnosis of canine IVDD.

Using a mixture of experience and after analysing the studies available, due to the fact that there is no standardised rehabilitation programme for canine IVDD I have outlined a guideline physiotherapy protocol below, which may be utilised either post-operatively or as a conservative only management programme (note this will vary with the severity of the case, hence exercises and timeframes may vary):

Stage 1 (Weeks 1 – 4):

-       Pain management: Discussion with the owner about pain medication pathway as prescribed by the veterinarian. How is the dog managing, and are they displaying any physical or behavioural issues? The physiotherapist may use adjuncts to help with pain relief, such as laser therapy, transcutaneous electrical nerve stimulation (TENS), pulsed electromagnetic fields (PEMF) or massage techniques such as myofascial release.

-       Lifestyle advice: Discussion with the owner about the management programme prescribed by the veterinarian. How long is the dog on crate rest, and how much time are they allowed outside? Discussions about continence, and guiding the owner with any mobility equipment, such as specialist harnesses.

-       Range of movement exercises: Taught in standing, sitting or lying as preferred, the physiotherapist can teach the owner both active and passive range of movement exercises for the limbs and the spine. The physiotherapist can also carry out manual techniques to improve spinal or thorax mobility, such as passive physiological intervertebral movements (PPIVM’s).

-       Early gait re-education and weightshifting exercises: As tolerated, the physiotherapist can begin to complete exercises to help with the dog’s balance and proprioception as they recover. Introduction of techniques such as the Bobath facilitation technique, NMES, use of mobility equipment and dynamic mobilisation exercises.

Stage 2 (Weeks 4 – 8):

-       Ongoing lifestyle advice: How is the dog progressing? Can they begin to build up more time outside of the crate, and progress their time outside? Usually, short walks can be introduced by this point, and guidance on frequency and intensity can be given to the owner.

-       Challenging strength, proprioception and gait: Increasing the difficulty of weightshifting exercises, progressing active control and strengthening of specific muscle groups and further gait re-education, without mobility equipment if possible. Unstable surfaces may be introduced if appropriate, such as wobble cushions.

-       Hydrotherapy: As the spinal wound heals, range of motion improves and the dog becomes stronger and more balanced, hydrotherapy and water treadmill can be added to the rehabilitation programme if indicated and approved by the veterinarian (this may be approved from as early as week 1 for some dogs!).

Stage 3 (Week 8+):

-       Dynamic mobility and advanced proprioceptive exercises: Exercises may include sit to stand/stand to sit (squat), lie to stand/stand to lie (push up), balancing on unstable surfaces, cavaletti poles and standing paw lifts.

-       Hydrotherapy and water treadmill progressions: Dogs may progress with endurance (time) and difficulty (such as changes of direction) with hydrotherapy if this is part of their rehabilitation programme. This can be carried on throughout their lifetime to maintain strength and stability.

-       Return to full function: Owners will be advised on long term lifestyle management, such as timeframes for increasing walking distance and managing day to day activities, such as using a ramp for stairs or car boots. Owners will be provided with an ongoing home exercise programme for the dog, with the knowledge that this will always need to be utilised to maintain strength and prevent re-occurrence of IVDD!

TO CONCLUDE

For dogs with IVDD, it seems that early intervention with a surgical approach has a successful outcome, particularly for dogs who are non-ambulatory when the disease is recognised. Hemi-laminectomy is reported to be the most common approach, often alongside fenestration at the affected disc. Nearly all studies analysed used a conservative approach, either with or without surgery. Physiotherapy interventions are crucial to aid the rehabilitation process, with a particular bias on strength and proprioception to return to full function.

References

Granger, N. (2024) A review of intervertebral disc disease classification in dogs: a fast-changing field! Available at: https://www.veterinary-practice.com/article/intervertebral-disc-disease-classification-dogs [Accessed 12th March 2025].

Hermansen, J., Kuricová, M. and Lipták, T. (2022) Intervertebral disc disease in dogs- the relationship between surgery and the timing of recovery. Folia Veterinaria, 66, (3), 54-59.

Jeong, I., Piao, Z., Rahman, M., Kim, S. and Kim, N. (2019) Canine thoracolumbar intervertebral disk herniation and rehabilitation therapy after surgical decompression: A retrospective study. Journal of Advanced Veterinary and Animal Research, 6, (3), 394-402.

Moore, S., Tipold, A., Olby, N., Stein, V., Granger, N. and Canine Spinal Cord Injury Consortium (2020) Current Approaches to the Management of Acute Thoracolumbar Disc Extrusion in Dogs. Frontiers in Veterinary Science, 7, (610).

Necas, A. (1999) Clinical aspects of surgical treatment of thoracolumbar disc disease in dogs. A retrospective study of 300 cases. Acta Veterinaria Brno, 68, 121-130.

Olby, N., Moore, S., Brisson, B., Fenn, J., Flegel, T., Kortz, G., Lewis, M. and Tipold, A. (2022) ACVIM consensus statement on diagnosis and management of acute canine thoracolumbar intervertebral disc extrusion. Journal of Veterinary Internal Medicine, 25, (36), 1570-1596.

UC Davis Veterinary Medicine (2024) Available at: https://vgl.ucdavis.edu/test/cddy-cdpa [Accessed 5th March 2025].

Zidan, N., Sims, C., Fenn, J., Williams, K., Griffith, E., Early, P., Mariani, C., Munana, K., Guevar, J. and Olby, N. (2018) A randomized, blinded, prospective clinical trial of postoperative rehabilitation in dogs after surgical decompression of acute thoracolumbar intervertebral disc herniation. Journey of Veterinary Internal Medicine, 32, (3), 1133-1144.