MANAGEMENT OF NS
Unfortunately, navicular syndrome is a chronic and degenerative condition, therefore it cannot be cured. However, modern management methods are effective in helping to keep horses sound, pain-free, and can increase competition longevity. In recent years, the prognosis has improved significantly due to the increased use of MRIs as well as the communication between farriers and veterinarians. The severity of clinical signs, the horse’s age, and intended use (including workload), are important considerations when developing a management plan. Younger horses with less severe clinical signs are the most suitable candidates for traditional therapy.
Non-surgical treatments include rest, corrective and therapeutic trimming or shoeing, as well as medical therapies including use of anti-inflammatories and other veterinary prescribed medications.
The biggest focal point in non-surgical treatment of NS is corrective shoeing. Careful evaluation of foot conformation and balance is key. Forces placed on the navicular region, including strain on the deep digital flexor tendon, can be reduced to help ease heel pain and lessen the severity of the condition. X-ray images of hoof angles are especially beneficial for farriers to assist with corrective shoeing.
As NS is a progressive degenerative problem within the navicular bone and its fibro-cartilage border, pain relief through the use of anti-inflammatory drugs should be discussed with your veterinarian. Long-term use of anti-inflammatory drugs is illegal in many equestrian competitions and can also have adverse health effects, especially on the digestive system.
The deposition of long-acting anti-inflammatory synthetic corticosteroid injections, into the two sacs of the navicular bursa within the coffin joint, is helpful to provide temporary relief from the constant pain and lameness of NS. A horse with a positive fetlock flexion test may benefit in the short term from a corticosteroid injection into the navicular bursa to reduce the inflammation. This can provide relief within 5-7 days and, once the horse is sound, it is considered best to put it back into light work to restore hoof circulation and weight-bearing.
There has also been the development of other new therapies for treatment. The use of injectable bisphosphonates, as recommended by veterinarians, has been useful to help improve bone density, increasing the capacity of the navicular bone to withstand mechanical loading in an exercising horse. This may reduce the risk of navicular fracture due to bone decalcification or osteoporosis, for example, in an aged jumping horse as it lands heavily on its front hooves on to a compacted surface.
The use of high-intensity sound waves or extracorporeal shock wave therapy (ECSWT) has been trialled to help relieve pain and shorten healing time of collagen tissue in the ligament attachments to the navicular bone within the coffin joint. It can especially be useful in conjunction with bisphosphonate therapy for bone repair.