Review Question - QID 7913

Radiographs showing broken hardware (screw head) and the clinical history are consistent with fracture nonunion; therefore, a CT scan is not required. Treatment for this nonunion may include various options. However, prior to any treatment, infection must be eliminated as a cause for the nonunion. Evaluation for infection can include laboratory studies such as erythrocyte sedimentation rate and C-reactive protein level.

Humeral nonunions can be aseptic or septic in nature, and preoperative workup will provide the surgeon appropriate information to decide on appropriate technique(s) for the procedure, as well as if a one or two stage procedure is needed. Propionibacterium acnes is known to be associated with upper extremity nonunions, but a septic nonunion can also be due to different bacteria as well.

King et al. report in their review article that various risk factors that may predispose patients to nonunion include obesity, osteoporosis, alcoholism, smoking, poor bone quality, and scar tissue. They also report that the rates of healing of humeral nonunions by traditional means of internal fixation with bone graft range from 70% to 92%, although in cases of infection, poorly vascularized beds, and open, segmental, or severely comminuted fractures, secondary bony healing may still be compromised.

Figures A and B show an atrophic humeral nonunion.

Incorrect Answers:
1: A CT is not needed to diagnose the atrophic nonunion seen here.
2: Application of a functional brace will not increase the healing rate.
4 and 5: Revision surgery without preoperative (or intraoperative) evaluation of infection is not recommended if an appropriate preoperative workup has not yet been completed.