Temporomandibular joint injuries and ankylosis in the cat

Abstract

<jats:title>Summary</jats:title><jats:p>Objective: To evaluate cause, location, treatment, and the clinical outcome of traumatic temporomandibular joint (TMJ) lesions and TMJ ankylosis in cats.</jats:p><jats:p>Methods: Cats with TMJ injuries were included in this study. Lesions were classified as luxations, fractures of the condylar process, and intra-articular temporal bone fractures. Signalment, cause and type of injuries, treatment methods, clinical outcome, complications and joint ankylosis were assessed and evaluated statistically.</jats:p><jats:p>Results: Temporomandibular joint lesions were observed in 82 of 161 cats with maxillofacial injuries. One hundred forty-nine TMJ lesions were determined in 112 joints. Falling was the most common cause and fractures of the condylar process were the most common types of injuries. Isolated TMJ injuries and caudal TMJ luxations were mainly caused by falling. Condylectomy was used in ankylosis, chronic luxation, reluxation and in two cases with multiple TMJ lesions. Ankylosis was observed in 10.97% of cases and was generally observed in fracture combinations of condylar process and mandibular fossa (Χ2 = 8.52; p &lt;0.05). No significant relationship between age and development of ankylosis (Χ2 = 3.995; p &gt;0.05) was found.</jats:p><jats:p>Conclusion: In contrast to previous studies, traumatic TMJ lesions were observed in a considerable amount of cats with maxillofacial injuries, and fractures of the condylar process were the most common type. Lesions caused by falling were mostly simple, whereas vehicular trauma caused more complicated lesions. Ankylosis did not appear as a rare condition. Any cat with TMJ injury is susceptible to the development of ankylosis.</jats:p>

Superficial temporal myofascial flap application in temporomandibular joint arthroplasty in a cat

“…1,2 TMJ injuries are most frequently reported secondary to a fall or after vehicular trauma, with ankylosis observed in approximately 10% of cases. 2,3 …”

Maxillofacial Injuries and Diseases That Cause an Open Mouth in Cats

“…Bilateral rostral luxation results in slight rostral protrusion of the mandibles. 2,26 Fractures of the mandibular ramus and coronoid process also frequently result in malocclusions as they are the location of insertion of the muscles of mastication. This often occurs with a fracture of the retroarticular process.…”

“…3,26 One study evaluating the diagnostic yield of radiographs and CT in cats with maxillofacial trauma showed that when an obvious injury such as mandibular symphyseal separation or mandibular fracture is present, up to 35.7 % of cases have at least one other less apparent injury such as a fracture of the retroarticular process. Advanced imaging such as computed tomography (CT) should be considered with maxillofacial trauma in a cat as studies have shown that trauma often results in multiple maxillofacial injuries.…”

“…3,26 One study evaluating the diagnostic yield of radiographs and CT in cats with maxillofacial trauma showed that when an obvious injury such as mandibular symphyseal separation or mandibular fracture is present, up to 35.7 % of cases have at least one other less apparent injury such as a fracture of the retroarticular process. 26 There was no significant relationship between age at the time of trauma and development of ankylosis. Treatment for TMJ luxation or fractures is dependent on the type of injury.…”

“…3 Computed tomography should be considered for any cat with maxillofacial trauma to allow for more accurate diagnosis, treatment planning, and prognosis. 26 A recent retrospective case series examining CT findings in dogs and cats with TMJ disease found that of the 42 cats evaluated, 17 cats had CT findings consistent with a TMJ disorder. Closed reduction following acute injury should be attempted to avoid formation of fibrous tissue within the joint space.…”