Does Indomethacin Reduce Heterotopic Bone Formation After Operations for Acetabular Fractures?

Abstract

We have studied prospectively the effect of indomethacin on the development of heterotopic ossification (HO) after the internal fixation of acetabular fractures. After operation 107 patients randomly received either a six-week course of indomethacin or no treatment against HO. Plain radiographs of 101 patients at a mean of 7.9 months after surgery showed HO in 47.4% of the 57 patients who received indomethacin and in 56.8% of the 44 who did not. This difference was not statistically significant. Heterotopic ossification of Brooker class II or more was seen in four patients (7%) with prophylaxis and in one without (p = 0.51). Measurements of the volume of HO on 3-D CT reconstructions showed a median value of 1.5 cm 3 in patients with indomethacin and 4.0 cm 3 in those without (p = 0.28). When only the 57 patients in whom the operation was carried out through either a Kocher-Langenbeck or an extended iliofemoral approach were included the indomethacin group showed a median volume of 1.7 cm 3 compared with 3.6 cm 3. On plain radiographs Brooker class II or above was seen in 9.4% of the patients receiving indomethacin and in 4.8% of those who did not. Indomethacin was therefore not effective in preventing ectopic bone formation after surgery for acetabular fractures. There was a significant association of male gender with volume of HO using a non-parametric analysis of variance.

Safety and efficacy of the extended iliofemoral approach in the treatment of complex fractures of the acetabulum

“…Heterotopic ossification was assessed on the plain AP radiograph of the pelvis and classified as grade 0 (none), grade 1 (minimal) or grade 2 (moderate to severe). 1,16 The grade-2 category included classes II to IV of Brooker et al 19 because the differences between these are small and do not necessarily indicate an increase in the severity of heterotopic ossification. This was seen in 63 patients (59%); in 31 (30%) it was graded as mild (grade 1), and 32 (30%) as moderate or severe (grade 2); in nine of these (8.5%) excision of the heterotopic bone was undertaken in order to improve movement (Fig.…”

“…Heterotopic ossification is considered to be clinically significant when it results in loss of 20% or more of movement in the hip. 1,16 While it is commonly seen after dissection of the abductor muscle mass from the external ilium, it is not usually clinically significant. 21 We used no formal prophylaxis and had an incidence of 30.2% for moderate to severe ossification.…”

“…15 No uniform protocol for the prophylaxis of heterotopic ossification was used, but a number of patients received indomethacin post-operatively as part of a separate study. 16 Radiological evaluation. The reduction of the fracture was evaluated by measuring the residual displacement at the level of the joint on the three views of the pelvis on plain films taken before discharge from hospital.…”

Risk Factors for the Development of Heterotopic Ossification After Acetabular Fracture Fixation

“…Complex exposures, double exposures, and concurrent trochanteric osteotomy are associated with increased risk [1,2,10,21,27,29]. In addition to surgical approach, other factors have been previously identified as potential risk factors for the development of ectopic bone, including male sex, concurrent craniocerebral trauma or thoracoabdominal trauma, Ttype acetabular fracture-associated findings such as sciatic nerve injury, femoral head injury, intraarticular debris, and delay to surgery [5,7,19,33]. Ipsilateral femur fracture may also be associated with increased risk [4].…”

Calcitonin Gene-Related Peptide (CGRP) and its Receptor (CGRP-R) in Osteoblasts from Iliac Crest and Heterotopic Bone Formations

“…Paraarticular and intramuscular bone formations cause restricted range of motion, pain and ankylosis [4,5]. Preventive measures are not very effective; mature ossifications can be resected, but the recurrence rate is high [6]. Neurotraumatically induced HO [7,8] may start within 2-3 weeks after the initial trauma [9], but its obvious onset has been described as late as several months following the precipitating event.…”