Magnetic resonance image findings in pug dogs with thoracolumbar myelopathy and concurrent caudal articular process dysplasia.

BACKGROUND: A retrospective case series study was undertaken to describe the magnetic resonance imaging (MRI) findings in Pug dogs with thoracolumbar myelopathy and concurrent caudal articular process (CAP) dysplasia. Electronic clinical records were searched for Pug dogs who underwent MRI for the investigation of a T3-L3 spinal cord segment disease with subsequent confirmation of CAP dysplasia with computed tomography between January 2013 and June 2017. Clinical parameters age, gender, neuter status, body weight, urinary or faecal incontinence, severity and duration of clinical signs were recorded. MRI abnormalities were described. Univariable non-parametric tests investigated the association between the clinical parameters and evidence of extra- or intra-dural spinal cord compression on MRI. RESULTS: 18 Pug dogs were included. The median age was 106 months with median duration of clinical signs 5 months. All presented with variable severity of spastic paraparesis and ataxia; 50% suffered urinary/faecal incontinence. In all cases, MRI revealed a focal increase in T2-weighted signal intensity within the spinal cord at an intervertebral level where bilateral CAP dysplasia was present; this was bilateral aplasia in all but one case, which had one aplastic and one severely hypoplastic CAP. MRI lesions were associated with spinal cord compression in all but one case; intervertebral disc protrusion resulted in extra-dural compression in 10 (56%) cases; intra-dural compression was associated with a suspected arachnoid diverticulum in 4 (22%) cases and suspected pia-arachnoid fibrosis in 3 cases (17%). There was no association between clinical parameters and a diagnosis of intra-dural vs extra-dural compression. CAP dysplasia occurred at multiple levels in the T10-13 region with bilateral aplasia at T11-12 most often associated with corresponding spinal cord lesions on MRI. CONCLUSIONS: All Pugs dogs in this study were presented for chronic progressive ambulatory paraparesis; incontinence was commonly reported. Although intervertebral disc disease was the most common radiologic diagnosis, intra-dural compression associated with arachnoid diverticulae/fibrosis was also common. Bilateral CAP aplasia was present in all but one Pug dog at the level of MRI detectable spinal cord lesions. A causal relationship between CAP dysplasia and causes of thoracolumbar myelopathy is speculated but is not confirmed by this study.

Long Term Outcome of Conservative Management or Surgical Treatment of Bovine Spastic Paresis: 79 Cases.

OBJECTIVE: To report the long term clinical outcome of calves treated surgically or managed conservatively for bovine spastic paresis of the gastrocnemius (BSP-G), quadriceps femoris muscle (BSP-Q), or mixed muscle involvement (BSP-M). STUDY DESIGN: Retrospective case study. ANIMALS: Calves (n = 79) with bovine spastic paresis. METHODS: Medical records of calves treated by partial tibial neurectomy or managed conservatively for bovine spastic paresis were analyzed for sex, breed, lineage history, and the onset, duration, and severity of clinical signs. Cases were classified as unilateral or bilateral BSP-G, BSP-Q, or BSP-M. Long term follow-up information was obtained by telephone questionnaire. RESULTS: The study group included 26 BSP-G (33%), 16 BSP-Q (20%), and 37 BSP-M (47%) calves. BSP-M and BSP-Q calves were significantly more bilaterally affected compared to BSP-G calves. Twenty-five of 26 BSP-G calves were treated surgically; 86% had complete resolution of clinical signs. Twenty-nine of 37 BSP-M calves were treated surgically; 81.5% improved, but none completely recovered. In all of the conservatively managed BSP-M calves, clinical signs gradually worsened. None of the BSP-Q calves were treated surgically; in 66.7%, clinical signs gradually worsened and 33.3% of calves spontaneously improved. CONCLUSION: Partial tibial neurectomy is advocated for the treatment of BSP-G and in selected cases of BSP-M. However, only partial resolution of clinical signs should be expected for BSP-M. No surgical treatment exists for BSP-Q calves, although spontaneous improvement is possible.