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Case 2: (a) T2-weighted sagittal and (b-d) T2-weighted transverse MRI at the level of T3-T4 showing similar triangular misshaping of the spinal cord and focal intramedullary hyperintensity owing to dorsolateral extradural compression caused by articular process and mild lamina hypertrophy (arrows) at T3-T4 in case 2. Mild associated intervertebral disc protrusion was also present in this case
Source publication
Case summary
A 9-year-old neutered female British Shorthair cat (case 1) and a 13-year-old neutered male domestic shorthair cat (case 2) showed signs of chronic T3–L3 myelopathy, which progressed over 6 and 12 months, respectively. On presentation, case 1 had moderate pelvic limb proprioceptive ataxia and ambulatory paraparesis, and case 2 was non-...
Context in source publication
Citations
... 3 TVCS secondary to articular process hypertrophy in two cats and diffuse idiopathic skeletal hyperostosis (DISH) in one cat have been reported. 4,5 The age of the cats in these studies was ⩾9 years. TVCS in young cats has not been reported. ...
... Previous studies reported TVCS owing to vertebral degeneration or vertebral hypertrophy in cats with DISH (n = 1) and TVCS secondary to articular process hypertrophy (n = 2). 4,5 Generally, DISH accompanies calcification and ossification of the ventrolateral aspect of at least four consecutive vertebral bodies. 9 In one report, new bone formation extended from T5 to S1 in a 9-year-old cat diagnosed with TVCS caused by DISH. 5 In the present study, the imaging features, which consisted of deformed vertebrae that were being restricted to T4, and the age of onset (2 years old) did not support a diagnosis of DISH. ...
... In two cats with TVCS due to articular process hyper trophy, the lesions were at the level of T3-T4 and T11-T12 at 13 years old and 9 years old, respectively. 4 In the present study, a single lesion originated from the vertebral body and pedicle of the T4 vertebra. As the cat had been kept indoors, it was unlikely that the spinal deformity resulted from trauma. ...
Case summary
A 2-year-old neutered female Scottish Fold cat was presented with an 8-week history of progressive back pain, paraparesis and decrease of postural reactions in both pelvic limbs. MRI showed spinal cord compression from both ventral sides, which originated from the T4 vertebral body and pedicle. The lesion compressing the spinal cord had a bone-like density on CT, and endoscopic surgery was performed to excise it. Histopathological examination of the resected tissue showed no evidence of malignancy and the lesion was diagnosed as vertebral hypertrophy. After surgery, the neurological status of the cat gradually improved. The cat was ambulant at the follow-up evaluation 2 weeks after surgery. Six months later, hindlimb paresis had improved considerably, and no recurrence was observed on CT.
Relevance and novel information
This is the first description of thoracic vertebral canal stenosis due to hypertrophy of a single vertebra in a young cat. Excision of the hypertrophic vertebra by endoscopic surgery is less invasive than open surgery and may give a good prognosis.
... The main differential diagnosis for APH in cats include angiomatosis (Schur et al., 2010;Hans et al., 2018), intervertebral disc disease (De Decker et al., 2017;Crawford et al., 2018), spinal arachnoid diverticulum (Adams et al., 2015), hamartoma (Taylor-Brown et al., 2018), vertebral malformation (Havlicek et al., 2009), spinal dural ossification (Antila et al., 2013), myelomeningocele (Ricci et al., 2011), neoplastic processes (Besalti et al., 2016) and inflammatory or infectious diseases (Marioni-Henry et al., 2004). Information about APH affecting cats, typical imaging characteristics, treatment and outcome is sparse, with only one recent case report about two cats showing single bilateral APH (T11-T12 in case 1 and T3-T4 in case 2) (Carletti et al., 2019). Before these two cases, thoracic vertebral canal stenosis due to bilateral APH at the level of T4-T5 has been reported in a nine-year-old female intact domestic Shorthair cat (Bossens et al., 2015), but in that particular case, the articular degenerative process was thought to be secondary to adjacent diffuse idiopathic skeletal hyperostosis (DISH). ...
... In this case series, the clinical presentation and imaging findings of multiple APH are described in one European and two British Shorthair cats. APH is a rarely reported cause of myelopathy in cats, and so far, only reported as a single site lesion (Bossens et al., 2015;Carletti et al., 2019). In the previously reported cases, the lesions were localized in the thoracic vertebral column. ...
... Predilection for APH appears to exist in older cats (middle-aged and senior). Similary to previously reported cases (Bossens et al., 2016;Carletti et al., 2019), the three cats of the present report were older than six years at the time of the diagnosis. Imaging findings of APH are compatible with enlargement of the articular processes, with these projecting into the vertebral canal and causing uni-or bilateral extradural compression of the spinal cord. ...
An eight-year-old British Shorthair (case 1), an eleven-year-old British Shorthair (case 2) and a six-year-old European Shorthair cat (case 3) showed signs of chronic T3–L3 myelopathy. Computed tomography of the thoracolumbar and lumbosacral region was performed in all three cases and magnetic resonance imaging was only performed in case 2. Cross sectional imaging revealed an enlargement of the articular process joints from T2 to T5 in case 1, from T11 to T13 in case 2 and from T10 to T13 in case 3 causing spinal cord compression. Based on the severity of the spinal cord compression, surgical decompression by hemilaminectomy was performed in case 1. In cases 2 and 3, conservative treatment was instituted, although this condition could have been an incidental finding in these two cases. To the authors’ knowledge, this is the first report describing the neurological signs, imaging findings and short-term outcome in cats with multiple thoracolumbar articular process hypertrophy.
... 3 Thoracic vertebral canal stenosis (TVCS) was recently documented to be among the 10 most common causes of spinal disease in the cat, 3 and a recent report described the successful surgical management of two cats with articular process hypertrophy causing TVCS. 4 However, there is little known about the clinical presentation, imaging findings and outcome of cats with this disease. ...
... A recent case report described thoracic vertebral canal stenosis in two cats, secondary to bilateral articular process hypertrophy. 4 It is unclear if this report describes a different disease process to that seen in the current study, given the appreciable articular process hypertrophy on imaging. However, in agreement with the current study, both cats were middle-aged or older at presentation and demonstrated a chronic, progressive T3-L3 myelopathy. ...
... In contrast to the present study, both cats had evidence of ventral spondylosis deformans at the site of vertebral stenosis, suggesting chronic vertebral instability and secondary articular process hypertrophy as the pathophysiology. 4 Overall, 6/9 cats affected by TVCS in the present study were of purebred descent and results suggested a breed-related predisposition in BSHs. Interestingly, this breed was previously reported to be more commonly diagnosed with thoracolumbar intervertebral disc disease. ...
Objectives
The aim of this study was to describe the clinical features, diagnostic imaging findings, treatment and outcome in cats with thoracic vertebral canal stenosis (TVCS).
Methods
Medical records and imaging studies of cats with TVCS were retrospectively reviewed. Outcome was acquired from patient records and from owners or referring veterinary surgeons via a telephone questionnaire. For each case, breed-, age- and sex-matched controls were identified with CT imaging of the thoracic vertebral column. For each cat, vertebral canal height was determined at three levels for each thoracic vertebra. Vertebral canal heights were compared between control cats of different breeds and between affected and control cats of the same breed.
Results
Nine TVCS cases were included. British Shorthairs and male neutered cats were over-represented (P <0.05). Median age at presentation was 9 years. All cats were presented for a chronic, progressive, painful, ambulatory, T3–L3 myelopathy. Five cats were treated conservatively, three surgically and one was euthanased. Two cats treated surgically demonstrated improvement of clinical signs and one demonstrated initial improvement followed by deterioration. Of the conservatively treated cats, three deteriorated and two improved. Compared with controls, affected cats had a lower vertebral canal height at multiple thoracic vertebral levels, being most prominent for British Shorthairs and domestic shorthairs (P <0.05). Unaffected British Shorthairs had a lower thoracic vertebral canal height at multiple levels than control domestic shorthairs (P <0.05).
Conclusions and relevance
TVCS should be considered a differential diagnosis in middle-aged to older cats presenting with a chronic, progressive, painful, T3–L3 myelopathy. The predisposition of British Shorthairs could be explained by a narrower vertebral canal in this breed.
This report describes a unique case of thoracic vertebral canal stenosis and vertebral instability in a 1 yr old Minuet cat. The cat presented with a history of chronic progressive nonambulatory paraparesis. Myelography with neutral and stress positions revealed dynamic compression at T1–4. Computed tomography and MRI revealed multiple sites of vertebral endplate osteolysis, adjacent bone sclerosis, intervertebral disk space narrowing, and spondylotic bridging within the cervical and cranial thoracic vertebral bodies and pedicles, particularly at C6–T4. The cat underwent a right-sided T1–4 hemilaminectomy and C7–T4 vertebral stabilization using positively threaded profile pins and polymethylmethacrylate. The cat fully recovered without any complication. The case highlights the potential for young cats, especially those with a chondrodysplastic condition, to develop vertebral canal stenosis and vertebral instability. The surgical treatment described herein resulted in an excellent outcome.
Objectives
The aim of the study was to describe the patient demographics, clinicopathological features and presumptive or final diagnoses in cats with myelopathies between the T1 and T6 vertebrae.
Methods
This retrospective multicentre case study enrolled cases between 2015 and 2022 that were diagnosed with myelopathies between the T1 and T6 vertebrae as the primary cause for the presenting clinical signs.
Results
A total of 21 cases matched the inclusion criteria, 13 males (11 castrated and 2 entire) and 8 spayed females (median age 93 months; range 5–192). Most of the cases presented with a chronic and progressive history (76% and 86%, respectively), with a median duration of 29 days (range 1–2880). At the time of presentation, 90% of the cases were localised to the T3–L3 spinal cord segments based on neurological examination. The most common underlying pathology was neoplasia (42.9%), followed by inflammatory (24%), anomalous (19%), degenerative (9.5%) and vascular (4.8%) disorders. The most common location was T3–T4 (29%), followed by T2–T3 and T5–T6 (19% each). The cutaneous trunci reflex was normal in 86% of the cases and most of the cases (71%) did not show spinal discomfort upon admission.
Conclusions and relevance
Neoplasia was the most common cause of cranial thoracic myelopathy in this study. The lack of pathognomonic clinical signs for this specific region highlights the importance of assessing the entire thoracolumbar region up to and including at least the T1 vertebra when investigating cases with signs consistent with a T3–L3 myelopathy.
