犬颞下颌关节强直的手术治疗

Surgical Treatment of Canine Temporomandibular Joint Ankylosis

4月龄雌性未绝育德国牧羊犬因无法打开口腔前来就诊。该犬1月龄时左侧面部被咬伤,后发现其口腔逐渐无法打开。临床检查见双侧颧弓下方不对称,触诊左侧颧弓下方有骨性突起。头部CT扫描显示左侧冠状突和颧弓畸形愈合,诊断为颞下颌关节强直。采取手术治疗,通过尾侧下颌骨节段性切除术解除颞下颌关节强直,骨切除范围从最后臼齿远中侧至下颌冠状突和角突连线前缘。术后半年复发,CT扫描显示下颌骨切除处骨断端已愈合。第二次手术切除第一臼齿远中侧至下颌冠状突和角突连线前缘的下颌骨,骨切除范围约2 cm,超过第一次手术。术后1年回访,患犬上下颌打开角度约70°,生活质量良好。该病例首次手术后复发的原因可能是因患犬年龄较小、骨切除范围不够和术后复健不积极。在骨骼愈合能力较强的年轻动物,采用部分下颌骨切除术治疗颞下颌关节强直时,应该扩大骨切除范围,防止骨断端接触。

A 4-month-old female intact German shepherd presented to our hospital with an inability to open the mouth.The patient was bitten on the left side of the face at 1 month of age and was found that its mouth failed to open gradually.Clinical examination revealed asymmetry in the ventral region of bilateral zygomatic arch and a rigid prominence on left side on palpation.CT showed malunion of the left coronal and zygomatic arch, and the diagnosis is temporomandibular joint ankylosisa.Surgical treatment was taken to release the temporomandibular joint ankylosis by caudal segmental mandibular osteotomy.The caudal mandible was removed, performed between the distal of the last molar and the rostral aspect of the line connecting the mandibular coronoid process and the angular process.Recurrence occurred six months after surgery and CT showed the bone edges at the mandibular resection healed.In the second operation, the mandible was removed from the distal of the first molar to the rostral aspect of the line connecting the mandibular coronoid process and the angular process.The extent of removal was approximately 2 cm which was beyond the first surgery.At 1-year postoperative follow-up, the patient can open its mouth up to about 70° and had a good quality of life.The recurrence after the first surgery in this case may be due to the young age, insufficient extent of osteotomy and inactive postoperative rehabilitation.Therefore, when treating temporomandibular joint ankylosis with segmental mandibular osteotomy in young animals who have a better bone healing ability, the extent of osteotomy should be expanded to prevent bone edges contact.