Intervertebral disc disease.

This article describes the functional anatomy of intervertebral discs and their relationship to the vertebrae and spinal cord. The pathologic events and clinical complications of intervertebral disc disease are described. A discussion of proper staging of disc disease and appropriate conservative management of degenerative disc disease is included.     

Intervertebral disc extrusion in six cats

Existing reports concerning intervertebral disc disease (IVDD) have focused almost exclusively on dogs, although a small number of individual case reports of IVDD of cats has been published. The medical records of six cats with IVDD were reviewed. Radiographic studies confirmed narrowed intervertebral disc spaces, mineralised intervertebral discs, and one or more extradural compressive lesions of the spinal cord in each cat. All disc extrusions were located in the thoracolumbar region. Surgical decompression of the spinal cord was achieved in all cats by means of hemilaminectomy and removal of compressive extradural material confirmed to be degenerative disc material. Good to excellent neurological recovery was noted in five of the six cats included in this report. Based on this review, it appears that IVDD of cats has many similarities to IVDD of dogs, and that healthy cats with acute intervertebral disc extrusion(s) respond favourably to surgical decompression of the spinal cord.     

Cervical intervertebral disc protrusion in two horses

Two horses with ataxia of all four limbs were found to have cervical intervertebral disc protrusion. Severe pelvic limb ataxia, proprioceptive deficits and spasticity were present in both horses with similar but less severe signs in the thoracic limbs. Cerebrospinal fluid analysis was within normal limits. Metrizamide myelography allowed definitive diagnosis in one case when a compression of the spinal cord was demonstrated at the level of the second intervertebral space. In the second case, an intervertebral disc protrusion between cervical vertebrae 6 and 7 was found at necropsy. Fiber degeneration with poor myelin staining characterized the spinal cords histologically.     

Intervertebral disc disease in Dachshunds radiographically screened for intervertebral disc calcifications

Background

Intervertebral disc disease (IDD) is a very common neurological disease, Dachshunds being the breed most often affected. In this breed, IDD has a hereditary background and is associated with intervertebral disc calcification (IDC), an indicator of severe intervertebral disc degeneration. In Finland, spinal radiography is used, when screening for IDC before breeding Dachshunds. We evaluated the association between IDC and IDD in Finnish Dachshunds radiographically screened for IDC.A questionnaire was sent to owners of 193 radiographically screened Dachshunds aged at least ten years. Clinical signs indicative of IDD were compared with IDC grade (grade 0 = no calcifications, grade 1 = 1 – 2 calcifications, grade 2 = 3 – 4 calcifications and grade 3 = 5 or more calcifications) and with age at the time of the radiographic examination. The diagnosis of IDD was confirmed by a veterinarian.

Results

IDD was common in the study population with 31% of dogs being affected. IDD and IDC were clearly connected (P < 0.001); IDD was rare in dogs with no calcifications (grade 0) and common in dogs with severe IDC (grade 3). The IDC grade was strongly positively associated with frequency of back pain periods (P < 0.001), and dogs with IDC grade 3 had frequent periods of pain. Reluctance to jump onto a sofa had a strong positive association with back pain. No association existed between age of the dog at the time of the radiographic examination and clinical signs indicative of IDD.

Conclusions

Radiographically detected IDC and IDD are common in Finnish Dachshunds and are strongly associated with one another. Spinal radiography is an appropriate screening tool for breeders attempting to diminish IDC and IDD in Dachshunds. A breeding program that screens dogs and selects against IDC can be expected to reduce the occurrence of IDD in future. Twenty-four to 48 months of age is a suitable age for screening.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-014-0089-4) contains supplementary material, which is available to authorized users.     

Asymmetric lumbosacral transitional vertebra and subsequent disc protrusion in a cocker spaniel

A 10-year-old cocker spaniel bitch presented with severe lumbosacral pain and acute onset left pelvic limb lameness. A diagnosis of asymmetric lumbosacral transitional vertebra with disc protrusion at L6-L7 was made by computed tomography. The cauda equina and left L6 nerve root were surgically decompressed with a dorsal laminectomy and lateral foraminotomy, which led to rapid resolution of the clinical signs.     

Results of surgical treatment for thoracolumbar disc protrusion

Ninety-nine dogs were treated by hemilaminectomy for thoracolumbar intervertebral disc protrusion. Most animals were 4–7 years old and chondrodystrophoid. The incidence of protrusion was higher at the thoracolumbar junction. Animals with paresis, pain, or pain and paresis had a greater recovery rate than dogs with paralysis. Résumé. La protrusion du disque intervertébral thoracolombaire a été traitée par hémi-laminectomie chez 99 chiens, la plupart âgés de 4 à 7 ans et atteints de chondrodystrophie. Les protrusions étaient plus fréquentes à la jonction thoraco-lombaire. Les animaux qui manifes-taient de la parésie ou de la douleur, ou de la parésie et de la douleur, se rétablissaient plus vite et mieux que les animaux paralysés. Zusammenfassung. Neunundneunzig Hunde wurden mit Hemilaminektomie bei thoraco-lumbaren Zwischenwirbelscheibenvorfall behandelt. Die meisten Tiere waren 4–7 Jahre alt und chondrodystrophoid. Die Häufigkeit von Diskushernien war höher am thoracolumbarem Über-gangsabschnitt. Tiere mit Parese, Schmerzen oder Schmerzen und Parese wurden häufiger wiederhergestellt als Hunde mit Paralyse.     

Caudal cervical disc protrusion in a Bengal tiger (Panthera tigris tigris).

A young adult male white Bengal tiger (Panthera tigris tigris) presented with hindlimb ataxia. Cervical and lumbar myelography revealed a compressive lesion of the cord at C(6-7). Corticosteroid therapy and confinement failed to provide lasting remission of signs. A modified, inverted cone ventral slot decompression was used to remove the fibrous material causing cord compression at C(6-7). Temporary Horner's syndrome and laryngeal paresis developed postsurgically because of excessive tissue retraction. The animal recovered normal ambulatory function 6 wk after surgery.     

Intervertebral disc extrusion and spinal decompression in a binturong (Arctictis binturong).

A 10-yr-old binturong (Arctictis binturong) developed an acute onset of hind limb paralysis. Neurological examination revealed sensorimotor paraplegia. Myelography and computed tomography demonstrated a ventrolateral extradural compression of the spinal cord centered over the L3-L4 intervertebral disc space. Spinal decompression was performed via hemilaminectomy and excision of degenerate nucleus pulposus, confirmed by histopathologic examination. The binturong regained slight motor function by day 8 postoperatively but succumbed to pancreatitis 19 days postoperatively.     

Decompressive laminectomy in thoraco-lumbar disc protrusion with paraplegia in the dog

Early decompressive laminectomy according to the method previously described (Funkquist, 1962b) has been performed during the period 1963-66 on a large number of cases of thoraco-lumbar disc protrusion with paraplegia at the Department of Surgery of the Royal Veterinary College, Stockholm, Sweden. In the author's own cases, twenty-six of the twenty-seven dogs operated on (96%) regained their ability to walk. Corresponding figures for the total number of cases operated on (including those of the author) by specially trained surgeons are seventy-three of eighty-two or 89%. In control cases treated conservatively twenty-one of forty-one dogs (51%) regained walking ability. In the cases operated on as emergencies by operators with mainly a general surgical training, operation results are conspicuously worse (thirty-one of forty-nine dogs or 63% regained walking ability). Relapse incidence was at least as high after laminectomy as conservative treatment, the former, as a rule, should be followed by a prophylactic disc evacuation in a subsequent operation. Zusammenfassung. Frühzeitige dekompressive Laminektomie nach der früher beschriebenen Methode (Funkquist, 1962) wurde wahrend der Periode 1963–1966 an einer grossen Zahl Fälle von thoracolumbarem Bandscheibenvorfall mit Paraplegie in der Chirurgischen Abteilung der Königlichen Tierärztlichen Akademie in Stockholm, Schweden, durchgeführt. In den Fällen des Autors erlangten 26 der 27 operierten Hunde (96%) ihre Gehfähigkeit wieder. Die entsprechenden Zahlen (einschliesslich der des Autors) für die Gesamtzahl der von Chirurgen mit Spezialausbildung durchgeführten Operationen sind 73 von 82 oder 89%. In den konservativ behandelten Kontrollfällen erhielten 21 von 41 Hunden (51%) ihre Gehfähigkeit zurück. Bei solchen Fällen, die als Notoperationen von Chirurgen hauptsächlich mit allgemeiner chirurgischer Ausbildung behandelt wurden, waren die Operationsergebnisse auffallig schlechter (31 von 49 Hunden oder 63% erhielten die Gehfähigkeit zurück). Da die Rückfallhäufigkeit nach Laminektomie mindestens so hoch ist wie nach konservativer Behandlung, sollte sich an die erstere in der Regel eine prophylaktische Bandscheibenevakuation in einrr späteren Operation anschliessen. Résumé. Une laminectomie précoce de décompression d'après la technique décrite antérieurement (Funkquist, 1962b), a été effectuée au cows de la période de 1963 à 1966 dans un grand nombre de cas de protrusion des disques thoraco-lombaires avec paraplégie au Département de Chirurgie, Veterinary College de Stockholm (Suède). Parmi les cas personnels de l'auteur 26 chiens sur 27 (soit 96%) ont pu remarcher. Le nombre correspondant pour la totalité des cas opérés (y compris ceux de l'auteur) par des chirurgiens entraînés était de 73 sur 82 chiens, soit 89% des cas. Pour les cas témoins la proportion des animaux traités conservativement et ayant pu remarcher, était de 21 sur 41 (51%). Dans les cas opérés en urgence par des opérateurs entraînés surtout en chirurgie générale, les résultats de l'opération étaient nettement moins favorables (31 chiens sur 49 seulement on pu remarcher, soit 63%). La fréquence des rechutes étant au moins aussi forte après laminectomie qu'après le traitement conservateur, on devrait procéder à une ablation du disque à titre prophylactique au cours d'une intervention ultérieure.     

Modified lateral spinal decompression in 61 dogs with thoracolurnbar disc protrusion

A modified lateral spinal decompression technique was performed in 61 dogs with thoracolumbar disc protrusion. Myelography combined with plain radiography and neurological examination determined the side of greatest compression in 93 per cent of the dogs. Disc material was retrieved in 98 per cent of the cases. Of the 35 non-ambulatory dogs, 95 per cent regained the ability to walk. The recovery time was three weeks.     

Acute intervertebral disc extrusion in a cat: clinical and MRI findings

A 5 year old, neutered male, domestic shorthaired cat had acute left hemiparesis and Horner's syndrome. Magnetic resonance imaging (MRI) revealed a loss of the normal signal from the nucleus pulposus of the intervertebral disc at C3/4, narrowing of the ventral subarachnoid space and slight dorsal displacement of the spinal cord and a focal hyperintense lesion affecting the left side of the spinal cord at the same level. The presumptive diagnosis was focal spinal cord oedema associated with intervertebral disc extrusion. A traumatic aetiology was suspected. The cat was treated conservatively and improved gradually over a period of 6 months.     

Diagnosis of lumbosacral intervertebral disc disease and protrusion in a horse using ultrasonographic evaluation and computed tomography

This case report describes the clinical presentation, diagnostic imaging modalities, treatment and post mortem evaluation of lumbosacral intervertebral disc protrusion in a mature Quarter Horse gelding 10 days after initial signs were noted. Grade 3 hindlimb ataxia, conscious proprioceptive deficits, urinary and faecal incontinence were present, which did not improve with anti‐inflammatories, antimicrobial therapy, corticosteroids, antioxidant therapy, cold‐laser therapy or electroacupuncture. Imaging modalities utilised ante mortem were computed radiography, transcutaneous and transrectal ultrasonography. Transrectal ultrasonography yielded findings highly suggestive of lumbosacral intervertebral disc protrusion and due to the lack of improvement and a poor prognosis, the horse was humanely subjected to euthanasia. Post mortem computed tomography, necropsy and histopathological evaluation confirmed lumbosacral intervertebral disc disease and protrusion into the spinal canal with subsequent impingement of the spinal nerve roots. Lumbosacral intervertebral disc protrusion as a clinical disease in the horse has not been previously described and should be included as a differential diagnosis in cases with acute hindlimb ataxia, proprioceptive deficits, and urinary and faecal incontinence.     

Spontaneous lumbar intervertebral disc protrusion in cats: literature review and case presentations

Reports on intervertebral disc disease in cats are rare in the veterinary literature. It has been postulated that intervertebral disc protrusion is a frequent finding during necropsy in cats, without having any clinical relevance (King and Smith 1958, King & Smith 1960a, King & Smith 1960b). However, a total of six cases with disc protrusions and clinically significant neurological deficits have been reported over the past decade. (Heavner 1971, Seim & Nafe 1981, Gilmore 1983, Littlewood et al 1984, Sparkes & Skerry 1990, Bagley et al 1995). As in dogs, there are also two types of intervertebral disc disease in cats: Hansen's type I (extrusion), and type II (herniation). Cervical spinal cord involvement was more commonly recognised in cats than the lumbar or the thoraco lumbar area. Cats over 15 years were mainly affected (King & Smith 1958, King & Smith 1960a, King & Smith 1960b). We describe two cats with lumbar intervertebral disc protrusions. Emphasis is placed on differential diagnoses, treatment and follow-up.     

Acute non-ambulatory tetraparesis attributable to cranial cervical intervertebral disc disease in a cat

A 10-year-old domestic longhair cat was presented for acute non-ambulatory tetraparesis. Clinicopathologic diagnostics revealed no abnormalities. Cervical myelogram revealed an extradural compressive lesion consistent with intervertebral disc disease of the C2-C3 intervertebral disc space. Ventral slot decompression confirmed the presence of extruded intervertebral disc material into the vertebral canal of the C2-C3 intervertebral space. The patient succumbed to cardiorespiratory arrest 3 days postoperatively.