Risk factors for the development of heterotopic ossification of the elbow in children with untreated chronic Monteggia fractures: a radiographic review of 274 cases

Abstract

Abstract Background The factors predicting the development of heterotopic ossification (HO) of the elbow in children with untreated chronic Monteggia fractures (UCMFs) remained unclear. This multicentre study was designed to evaluate the radiographic data from paediatric patients with UCMFs and to identify the risk factors for HO formation and their radiographic characteristics. Materials and methods We retrospectively reviewed 274 patients (mean age at injury: 5.82 ± 2.62 years) with UCMFs with all types of anterior (group A) and non-anterior (group B) radial head (RH) dislocations. Radiographs were used to assess the presence, size and bone density of HO. The risk factors evaluated included age at injury, sex, laterality, interval from injury to diagnosis, presence of radial or median nerve injury, immobilization of the fractured ulna after injury, direction of RH dislocation and distance of RH dislocation (DD-RH). The results were compared with 76 patient demographics-matched paediatric acute Monteggia fractures (PAMFs) undergoing surgery within 48 h after injury. Results The HO rate (13.1%) in children with UCMFs was significantly higher than that (0%) in children with PAMFs (P = 0.001). The incidence of HO (14.5%) in group A was significantly higher than that (0%) in group B (P = 0.032). Age at injury and DD-RH were confirmed as risk factors for HO in patients with UCMFs by both univariate and logistic regression analyses (P 6.78 years and DD-RH 6.78 years, and DD-RH < 1.59-fold of the narrowest radial neck width were more likely to develop HO. The bone density of HO increases with age at injury and interval from injury to diagnosis. Timely RH reduction after acute injury may prevent HO. Level of evidence: III.

Keywords

• Chronic Monteggia fracture
• Acute Monteggia fracture
• Children
• Heterotopic ossification
• Risk factors