Case Description—A 5-year-old neutered male English Bulldog was evaluated for intermittent closed-mouth jaw locking of approximately 1 week's duration.
Clinical Findings—Initial physical examination revealed a nonpainful inability to open the jaw with and without manual assistance; however, manipulation of the jaw after the dog was sedated for diagnostic imaging restored jaw function. Anesthesia was subsequently induced, and computed tomography was performed with the jaw open and closed; contrast agent–enhanced images of the closed jaw were also obtained. No abnormalities of the temporomandibular joints or retrobulbar space were detected. Fluoroscopic examination of movement of the temporomandibular joints revealed a dynamic interference of the rostrodorsal aspect of the coronoid process of the left mandibular ramus with the medial surface of the frontal process of the left zygomatic bone or the left orbital ligament.
Treatment and Outcome—Partial excision of the coronoid process of the left mandibular ramus was performed. The dog recovered without complication and was able to open and close its jaw and eat within 6 hours after surgery. No additional episodes of jaw locking were detected during the 6 months after surgery.
Clinical Relevance—To the authors' knowledge, closed-mouth jaw locking in animals attributable to dynamic interference of the rostrodorsal aspect of the coronoid process of a mandibular ramus with the medial surface of the frontal process of a zygomatic bone or an orbital ligament has not been described. Surgical excision of the coronoid process of the mandibular ramus appeared to provide a successful outcome in the dog of this report.
OBJECTIVE To radiographically evaluate and compare changes in the patellar ligament of dogs following tibial plateau leveling osteotomy (TPLO) and tibial tuberosity advancement (TTA).
DESIGN Retrospective case series.
ANIMALS 106 dogs that underwent TPLO (n = 59) or TTA (n = 47) for unilateral rupture of the cranial cruciate ligament at a private veterinary hospital from August 2009 through September 2012.
PROCEDURES Medical records were reviewed to collect information on dog signalment, surgical procedure, whether arthrotomy had been performed, pre- and postoperative measurements of patellar ligament angle (PLA) and tibial plateau angle (TPA), and preoperative and follow-up measurements of patellar ligament thickness.
RESULTS For dogs that underwent TTA, thickening of the distal portion of the patellar ligament was identified radiographically in 43 (92%) dogs at the first follow-up examination and 36 (77%) at the second follow-up examination. For dogs that underwent TPLO, these numbers were 57 (97%) and 54 (92%), respectively. A significant decrease in patellar ligament thickness was identified between the first and second follow-up examinations for TTA but not TPLO. Mean ± SD PLA following TTA was 89.46 ± 5.54°, representing a mean difference from the preoperative PLA of 11.86 ± 5.3°; following TPLO, mean TPA was 12.61 ± 4.03°, representing a mean difference from the preoperative TPA of 16.74 ± 7.13°.
CONCLUSIONS AND CLINICAL RELEVANCE Patellar ligament thickening occurred following TPLO and TTA in dogs. The clinical relevance of this thickening remains unknown.