Wu et al identified risk factors for nonunion of a femoral shaft fracture stabilized with an intramedullary nail in a middle-aged adult. These can help to identify a patient who may require more aggressive management. The authors are from Tzu Chi University and Hualien Tzu Chi Hospital in Taiwan.

Patient: femoral shaft/diaphyseal fracture with intramedullary nail fixation. age 40 to 70 years


Outcome: nonunion at 1 year, with need to reoperation


The period of normal union is usually 3 to 6 months but can take longer.


Risk factors for nonunion:

(1) obesity (BMI >= 30 kg per square meter)

(2) hypertension

(3) diabetes mellitus

(4) fracture at the proximal third junction

(5) comminuted fracture


At 6 months patients with fracture union had a RUST score (range from 4 to 12) of 9.2 +/- 1.1. Patients with nonunion had a RUST score of 6.8 +/- 1.6. So a RUST score <= 8 at 6 months is associated with nonunion.

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