Effects of postoperative radiotherapy for temporomandibular joint ankylosis after gap arthroplasty: an animal study using sheep.

PURPOSE: The aim of the present study was to examine the effects of postoperative irradiation on reducing heterotopic bone formation after gap arthroplasty release of temporomandibular joint ankylosis. MATERIALS AND METHODS: Five sheep underwent induction of right temporomandibular joint ankylosis. After 3 months, the ankylosis was released by gap arthroplasty. At 24 hours after the release, they received a single radiation dose of 10 Gy. All sheep were sacrificed at 3 months after gap arthroplasty release. The body weight, jaw opening amount, and radiographs were measured at key intervals, with histologic assessment after death. The findings were compared with those in a control group treated with gap arthroplasty without irradiation. RESULTS: The clinical measurements, radiographs, and histologic findings all revealed less evidence of reankylosis in the irradiated sheep. CONCLUSION: The results of the present study have shown that a single radiation dose at 24 hours after gap arthroplasty for temporomandibular joint ankylosis inhibits heterotopic ossification.

Long-term results of radiation prophylaxis for heterotopic ossification in the temporomandibular joint.

PURPOSE: To assess the long-term efficacy and toxicity of radiation therapy (RT) for postoperative prophylaxis of recurrent heterotopic ossification (HO) in the temporomandibular joint (TMJ). PATIENTS AND METHODS: Twelve patients (18 joints) with bony ankylosis of the TMJ from HO were referred to undergo RT after arthrotomy with osseous recontouring, gap arthroplasty, or costochondral grafting. Treatment consisted of 10 Gy in 5 daily fractions to a field encompassing the TMJ with an adequate margin. RT was initiated 1 to 3 days postoperatively. Response to therapy was assessed by routine x-ray films obtained preoperatively, immediately postoperatively, and at follow-up by use of the Turlington-Durr grading system. Treatment efficacy was defined as freedom from HO re-formation requiring further surgical intervention. Efficacy and toxicity data were obtained from review of the medical records and were augmented by telephone interview of patients when possible (6 patients, all with follow-up >16 years). Efficacy rates by patient were estimated by the Kaplan-Meier method. RESULTS: The median follow-up after RT was 16.4 years (range, 2.5-19.2 years). Symptomatic re-formation of HO requiring further surgery occurred in 5 patients (7 joints). Treatment efficacy rates were 71% (95% confidence interval [CI], 44-99) at 5 years and 48% (95% CI, 15-80) at 10 years. Of the 6 patients contacted regarding late toxicity, 2 had clinical xerostomia (grade 1, CTCAE v3.0) attributable to RT; no other late RT-related toxicities were noted. None of the 12 patients had malignancy attributable to RT. CONCLUSIONS: Postoperative RT prevented re-formation of TMJ HO in 50% of treated patients long term. Late toxicities from RT were mild and infrequent.

Operative release of ankylosis of the elbow due to heterotopic ossification. Surgical technique.

BACKGROUND: Although uncommon, complete ankylosis of the elbow secondary to heterotopic ossification results in severe disability. The results of surgical management remain unclear. METHODS: A single surgeon used a consistent operative technique to treat complete osseous ankylosis of the elbow in eleven limbs in seven patients after severe burns and in nine elbows in eight patients after trauma. The elbows in the burn cohort were more often ankylosed in extension (average, 47 degrees of flexion) compared with those in the trauma cohort (66 degrees of flexion), and they had more skin problems (three elbows required a free microvascular muscle transfer for coverage) and associated problems of the shoulder, wrist, and hand. RESULTS: Four patients in the burn cohort and three patients in the trauma cohort failed to regain at least 80 degrees of ulnohumeral motion. After a repeat release in three burn patients and three trauma patients, and at an average follow-up of forty months, the average arc of ulnohumeral motion was 81 degrees in the burn cohort and 94 degrees in the trauma cohort. Six of the eleven limbs in the burn cohort and five of the nine in the trauma cohort had a good result. The average score according to the American Shoulder and Elbow Surgeons elbow assessment form was 72 points for the burn cohort and 76 points for the trauma cohort. CONCLUSIONS: Osseous ankylosis of the elbow is a severely disabling problem, and attempts to regain mobility are both worthwhile and safe. The results are comparable when the ankylosis is caused by burns or trauma despite the greater complexity of osseous ankylosis in the burned arm. Patients and surgeons should be aware of the small risk of recurrent heterotopic ossification and the moderate risk of pain or recurrent contracture after operative release.

Postoperative ionizing radiation in the management of heterotopic bone formation in the temporomandibular joint.

PURPOSE: The purpose of this study was to evaluate the effectiveness and possible morbidity of postoperative low-dose ionizing radiation in the treatment of recurrent temporomandibular joint ankylosis. PATIENTS AND METHODS: From 1987 to 1996, 14 patients with a history of multiple surgeries and recurrent temporomandibular joint ankylosis were treated postsurgically with radiation therapy. The treatment regimen initially selected was a postoperative dose of 2,000 rads in 10 fractions. Subsequently, 1,000 rads was found to be as effective. The success of therapy was assessed by means of serial radiographic studies and clinical examination, with the longest follow-up being 9 years. RESULTS: Thirteen of 14 patients (93%) showed radiographic evidence of decreased heterotopic bone formation. No patient redeveloped ankylosis. A transient xerostomia appeared to be the only significant complication. CONCLUSION: Low-dose ionizing radiation therapy, consisting of 1,000 rads given in five fractionated doses soon after surgical treatment, reduces recurrent heterotopic bone formation and appears to be a useful adjunct to the surgical management of temporomandibular joint ankylosis.

Radiation treatment of heterotopic bone formation in the temporomandibular joint articulation.

PURPOSE: The efficacy and toxicity of radiation therapy used for preventing re-formation of heterotopic bone involving the temporomandibular joint are assessed. METHODS AND MATERIALS: Ten patients (15 TMJs) with bony ankylosis of the TMJ were referred after reconstruction with costochondral graft, gap arthroplasty, or debridement of heterotopic bone. Treatment consisting of 10 Gy was delivered early postoperatively to a field encompassing the TMJ with adequate margin. Response to therapy was assessed by comparison of routine roentgenograms obtained preoperatively, immediately postoperatively, and at last follow-up; the Turlington-Durr grading system was used. Median duration of postoperative follow-up was 19 months. RESULTS: Radiation therapy prevented ectopic bone re-formation in 10 (69%) of 15 TMJs with prior bony ankylosis. Of the 15 TMJs, 13 (87%) had improvement in their Turlington-Durr scores compared with the preoperative scores. Development of ectopic bone formation was prevented in 9 (90%) of 10 TMJs rendered Turlington-Durr grade 0 postoperatively. Eight of the 10 patients have remained asymptomatic. Treatment was well tolerated. The only complication experienced was parotitis in three patients. CONCLUSION: Radiation therapy is useful for prevention of heterotopic bone redevelopment after TMJ operation. We recommend 10 Gy in 5 fractions beginning early postoperatively for high-risk patients. This strategy appears beneficial in this young patient population, who suffer significant pain and functional impairment in the TMJ articulation.

Cobalt radiation to prevent reankylosis after repeated surgical failures: report of case.

This is the first reported case of the use of cobalt 60 radiation for the prevention of recurrent TMJ ankylosis after repeated surgical treatment had failed. Although radiation therapy is not usually indicated for benign conditions, 2,000 rads can be used safely to treat this crippling condition. Although no conclusions can be drawn from a single case, successful treatment of this patient is indicated by a 3 1/2-year follow-up.