Temporomandibular joint injuries and ankylosis in the cat

Summary

Objective: To evaluate cause, location, treatment, and the clinical outcome of traumatic temporomandibular joint (TMJ) lesions and TMJ ankylosis in cats.

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.

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 <0.05). No significant relationship between age and development of ankylosis (Χ² = 3.995; p >0.05) was found.

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.

Keywords

Temporomandibular joint - luxation - fracture - ankylosis - cat

• References

• 1 Scott HW. The Skull and mandible. In: Coughlan A, Miller A. editors. BSAVA Manual of Small Animal Fracture Repair and Management. Hampshire: BSAVA; 1998. pg. 115-132
• 2 Smith MM, Kern DA. Skull trauma and mandibular fractures. Vet Clin North Am Small Anim Pract 1995; 25: 1127-1148.
• 3 Verstraete FJM. Maxillofacial fractures. In: Slatter DH. editor. Textbook of Small Animal Surgery. Philadelphia: Saunders; 2003. pg. 2190-2207
• 4 Egger EL. Skull and mandibular fractures. In: Slatter DH. editor. Textbook of Small Animal Surgery. Philadelphia: Saunders; 1993. pg. 1910-1921
• 5 Piermattei DL, Flo GL, DeCamp CE. Fractures and luxations of the mandible and maxilla. In: Brinker, Piermattei and Flo's Handbook of Small Animal Orthopedics and Fracture Repair. Philadelphia: Saunders-Elsevier Inc.; 2006. pg. 717-736
• 6 Stead C. The temporomandibular joint. In: Houlton JEF, Collinson RW. editors. Manual of Small Animal Arthrology. Iowa State Press, BSAVA; 1994. pg. 325-336
• 7 Wiggs RB, Lobprise HB. Oral surgery. In: Wiggs RB, Lobprise HB. editors. Veterinary Dentistry: Principles and Practice. Philadelphia: Lippincott-Raven Publishers; 1997. pg. 232-258
• 8 Wiggs RB, Lobprise HB. Oral fracture repair. In: Wiggs RB, Lobprise HB. editors. Veterinary Dentistry: Principles and Practice. Philadelphia: Lippincott-Raven Publishers; 1997. pg. 259-279
• 9 Umphlet RJ, Johnson AL. Mandibular fractures in the cat. a retrospective study. Vet Surg 1988; 17: 333-337.
• 10 Legendre L. Maxillofacial fracture repairs. Vet Clin North Am Small Anim Pract 2005; 35: 985-1008.
• 11 Salisbury SK, Cantwell HD. Conservative management of fractures of the mandibular condyloid process in three cats and one dog. J Am Vet Med Assoc 1989; 194: 85-87.
• 12 Eisner ER. Bilateral mandibular condylectomy in a cat. J Vet Dent 1995; 12: 23-26.
• 13 Lantz GC. Temporomandibular joint ankylosis: surgical correction of three cases. J Am Anim Hosp Assoc 1985; 13: 173-177.
• 14 Maas CPHJ, Theyse LFH. Temporomandibular joint ankylosis in cats and dogs: a report of ten cases. Vet Comp Orthop Traumatol 2007; 20: 192-197.
• 15 Meomartino L, Fatone G, Brunetti A. et al. Temporomandibular ankylosis in the cat: a review of seven cases. J Small Anim Pract 1999; 40: 7-10.
• 16 Okumura M, Kadosawa T, Fujinaga T. Surgical correction of temporomandibular joint ankylosis in two cats. Aust Vet J 1999; 77: 24-27.
• 17 Sullivan M. Temporomandibular ankylosis in the cat. J Small Anim Pract 1989; 30: 401-405.
• 18 Van Ee RT, Pechman RD. False ankylosis of the temporomandibular joint in a cat. J Am Vet Med Assoc 1987; 191: 979-980.
• 19 Piermattei DL. The head. In: An Atlas of Surgical Approaches to the Bones and Joints of the Dog and Cat. Philadelphia: Saunders; 1993. pg. 31-43
• 20 Cetinkaya MA, Yardimci C, Kaya U. Lingual arch bar application for treatment of rostral mandibular body fractures in 16 cats. Vet Surg 2011; 40: 457-463.
• 21 Bennett JW, Kapatkin AS, Manfra Manetta S. Dental composite for the fixation of mandibular fractures and luxations in 11 cats and 6 dogs. Vet Surg 1994; 23: 190-194.
• 22 Whitney WO, Mehlhaff CJ. High-rise syndrome in cats [erratum in: J Am Vet Med Assoc 1988; 192: 542]. J Am Vet Med Assoc 1987; 191: 1399-1403
• 23 Vnuk D, Pirki B, Matici D. et al. Feline high-rise syndrome: 119 cases (1998-2001). J Feline Med Surg 2004; 6: 305-312.
• 24 Bar-Am Y, Pollard RE, Kass PH. et al. The diagnostic yield of conventional radiographs and computed tomography in dogs and cats with maxillofacial trauma. Vet Surg 2008; 37: 294-299.