Heterotopic ossification formation after fractures about the elbow.

INTRODUCTION

Heterotopic ossification (HO) is a well-known sequela after an elbow injury and is widely studied given the associated morbidity. The anatomic location of HO development for specific elbow injuries has not been reported. The purpose of this study was to describe the precise, anatomic location of HO development after different peri-articular elbow injuries.

METHODS

A retrospective chart review was performed for patients with peri-articular elbow fracture and/or dislocation who underwent an elbow contracture release. The injuries were grouped into coronal shear distal humerus/AO 13.B3 (CSDH), distal humerus/AO 13.A, 13.B1, B2 or 13.C (DH), olecranon/AO 21.B1 (OL), radial head/AO 21.B2 (RH), extra-articular proximal radius and ulna/AO 21.A (EAPRU) fractures and elbow dislocations (DL). The HO location was determined by reviewing elbow radiographs and CT scans and were classified as anterior capsule, medial or lateral collateral ligaments, and posterior capsule/triceps insertion.

RESULTS

The study consisted of 49 patients, such as 6 CSDH, 13 DH, 6 OL, 21 RH, 4 EAPRU fractures and 20 elbow DL. All CSDH and RH fractures and 19/20 elbow DL developed HO in the collateral ligaments, while 12/13 DH fractures developed an anterior capsule HO. All 6 OL fractures developed HO posteriorly, and 3/4 EAPRU fractures developed a proximal radioulnar synostosis.

CONCLUSIONS

Our findings suggest that the location of HO development is specific to the injury type and is influenced by the soft tissues involved. This is consistent with the understanding that HO is the abnormal ossification of normal structures.