Evaluation of the intervertebral disk, vertebral body, and spinal cord for changes secondary to percutaneous laser disk ablation.

OBJECTIVE: To evaluate the intervertebral disk, vertebral endplates, and spinal cord for perioperative changes secondary to percutaneous laser disk ablation (PLDA) and correlate findings to clinical outcomes in dogs receiving thoracolumbar PLDA. STUDY DESIGN: Blinded study. ANIMALS: Thirty dogs. METHODS: Magnetic resonance imaging (MRI) was performed before PLDA (control/Group C), immediately following PLDA (Group I), and 3 months later (perioperative/Group P). Dogs were followed 3 years. Groups and dogs were randomized for evaluation. Two radiologists were blinded to each MRI study and dog. Each radiologist evaluated the disk, vertebral body, and spinal cord at each disk space receiving PLDA. RESULTS: Mean disk degeneration was increased in Group P at L1-2 (p < .0001) and L2-3 (p = .0081). Both radiologists identified mild diskitis (1%-15%) in Group P (radiologist 1, p < .0001; radiologist 2, p = .0012). Cranial endplate lesions were identified in Group P at T11-12 (p = .0353), T13-L1 (p = .0026), and L4-5 (p = .0210). Lesions were identified in the caudal endplates of all eight disk spaces in Group P: T10-11 (p = .0004), T11-12 (p < .0001), T12-13 (p < .0001), T13-L1 (p < .0001), L1-2 (p < .0001), L2-3 (p < .0001), L3-4 (p < .0001), and L4-5 (p < .0001). There was no disk extrusion or spinal cord lesions identified. CONCLUSION: This study evaluated effects that may occur secondary to PLDA, using MRI. Although vertebral body changes were identified, they did not correlate with clinical complications. CLINICAL SIGNIFICANCE: PLDA appears to be a safe, effective procedure performed on thoracolumbar disks to reduce recurrence of intervertebral disk herniation (IVDH) in dogs that previously experienced IVDH, despite the appearance of visible vertebral endplate lesions and mild diskitis on MRI.

Quantitative assessment of intravenous regional limb perfusion of tiludronate as an adjunctive treatment for lameness caused by navicular syndrome in horses.

OBJECTIVE To determine effects for 2 IV regional limb perfusion (IVRLP) protocols involving tiludronate on lameness of horses with navicular syndrome. ANIMALS 15 horses with bilateral forelimb navicular syndrome. PROCEDURES Shoeing and anti-inflammatory injection into the distal interphalangeal joint (DIPJ) of both forelimbs (day 0) were performed on all horses. On day 14, horses received 1 of 3 IVRLPs consisting of 0.1 mg of tiludronate/kg (low-dose tiludronate [LDT]; n = 5), 0.2 mg of tiludronate/kg (high-dose tiludronate [HDT]; 5), or saline (0.9% NaCl) solution (placebo; 5); treatments were repeated at days 24 and 34. Lameness severity of both forelimbs was evaluated via subjective evaluation and force plate analysis before and after shoeing on day 0 and at days 14, 34, 60, and 120. Mean subjective lameness score and peak vertical ground reaction force (PVGRF) for the more severely lame forelimb (LFL) and both (combined) forelimbs (CFL) were compared over time. RESULTS For all horses, mean PVGRF for the LFL and CFL was increased at 14 days. No difference in mean subjective lameness score or mean PVGRF was detected within groups at any time. Mean PVGRF of the CFL was higher for the HDT group than the LDT and placebo groups only at 120 days. CONCLUSIONS AND CLINICAL RELEVANCE Use of the tiludronate IVRLP protocols described here provided no further improvement in lameness over therapeutic shoeing and anti-inflammatory injection of the DIPJ in horses with navicular syndrome. However, HDT-treated horses were objectively less lame than LDT- or placebo-treated horses at 120 days.

Catastrophic complication following injection and extracorporeal shock wave therapy of a medial femoral condyle subchondral cystic lesion in a 14 year old Arabian mare.

This report describes fibrous cyst lining injection and extracorporeal shock wave therapy (ESWT) of a medial femoral condyle (MFC) subchondral cystic lesion (SCL) resulting in catastrophic MFC fracture in an Arabian mare. The mare was presented for evaluation of a severe hind limb lameness of approximately 4 months duration. On presentation, a non-weight bearing lameness of the left hind limb with severe effusion and soft tissue swelling of the stifle region was noted. Radiographic evaluation of the stifle revealed a large SCL of the MFC with associated osteoarthritis. Arthroscopic guided intra-lesional injection of the SCL with corticosteroids and autologous bone marrow concentrate was performed followed by ESWT of the MFC. The mare was discharged walking comfortably 48-hours post-operatively. An acute increase in lameness was noted 14 days post-operatively. Imaging revealed catastrophic fracture of the left MFC. Possible mechanisms leading to failure of the MFC secondary to the described treatment are discussed.

Quantitative assessment of two methods of tiludronate administration for the treatment of lameness caused by navicular syndrome in horses.

OBJECTIVE: To determine effects of 2 tiludronate administration protocols on measures of lameness in horses with navicular syndrome (NS). ANIMALS: 12 horses with bilateral forelimb NS. PROCEDURES: Horses were randomly assigned to receive tiludronate (1 mg/kg), diluted in 5 L of isotonic electrolyte solution and delivered through a jugular vein catheter (systemic treatment group; n = 6), or tiludronate (0.1 mg/kg), diluted with saline (0.9% NaCl) solution to a total volume of 35 mL and delivered into the lateral digital vein of each forelimb with an IV regional limb perfusion (IVRLP) technique (IVRLP group; 6). Mean peak vertical ground reaction force (pVGRF) measured with a stationary force plate and subjective lameness scores (SLSs) were recorded before (day -1) and at predetermined time points after tiludronate administration on day 0. Mean pVGRFs (standardized as percentage body weight of force) and mean SLSs for the most lame forelimb and for both forelimbs of horses in each group were compared with day -1 values to determine treatment effect. RESULTS: Mean pVGRF for both forelimbs and for the most lame forelimbs of systemically treated horses were significantly increased on days 120 and 200, compared with day -1 results. No significant difference in mean pVGRF was observed for IVRLP-treated horses. The SLSs were not improved at any time point following systemic treatment and were improved only on day 120 following IVRLP. CONCLUSIONS AND CLINICAL RELEVANCE: Tiludronate (1 mg/kg, IV) as a single systemic treatment appeared to be beneficial for horses with NS, but no horses were judged as sound during the study period. Additional research on IVRLP with tiludronate is needed before this method can be recommended.

Segmental jejunal entrapment, volvulus, and strangulation secondary to intra-abdominal adhesions in a dog.

A 4 yr old, castrated male dachshund was presented for lethargy, restlessness, a "hunched" posture, and a painful abdomen. A gastric foreign body had been surgically removed 24 mo previously. Exploratory celiotomy revealed a devitalized segment of jejunum with twisted mesentery. Several adhesions and fibrous bands were present within the abdomen, presumptively from the previous gastric foreign body surgery. Histopathology determined that a fibrous tissue band caused entrapment of the segment of intestine and its mesentery resulting in volvulus and ischemic necrosis of the intestine. This case is unique because it involved a focal area of the jejunum that was incarcerated in fibrous adhesions.