Lower extremity fractures in patients with spinal cord injury characteristics, outcome and risk factors for non-unions

Context: Sublesional osteoporosis is an important sequel after spinal cord injury (SCI) resulting in a high incidence of fractures and impaired osseous healing due to altered bone metabolism. The following study aims to identify demographic characteristics and outcome of patients with SCI with lower extremity fractures.

Design: Retrospective observational study.

Setting: Level-I cross-regional trauma center.

Participants: All patients with SCI suffering from osteoporotic/pathologic fractures during an 11-year-period (01/2003-12/2013) at the Center for Spinal Cord Injuries (Trauma Center Murnau) were analyzed via a chart review.

Outcome measures: Demographics, surgical and radiologic outcome as well as complication rate were assessed with a special emphasis on union rates and independent risk factors for non-unions.

Results: We identified 132 patients (105 males) who fulfilled the inclusion criteria. Most of them were paraplegic (n=101) and showed motor complete syndromes (n=119). Supracondylar femur fractures were the most prevalent in this study (n=47). We observed a non-union rate of 15.9% (n=21). The development of pseudarthrosis was associated with the time interval since the initial SCI (P < 0.010), delayed in-patient submission (P < 0.038), fracture classification (P < 0.002) and the localization of the fracture (P < 0.0001). The overall complication rate was 16.7%. All dislocated subtrochanteric femur fractures (Garden III and IV) (n=10) developed a non-union, regardless of their management (conservative or surgical). The following independent predictors for non-unions were identified: fracture localization (P < 0.0002), fracture classification (P < 0.056), and fracture management (P < 0.036).

Conclusions: Even though modern techniques allow surgical interventions in bones with reduced mineral density, non-unions remain a common complication in patients with SCI. Risk factors for non-unions of lower extremity fractures are identified.