Session XII - Upper Extremity

Sat., 10/7/06 Upper Extremity, Paper #66, 3:06 pm

The Axillary Radiograph in Determining Management of Surgical Neck Fractures

Anthony DeLuise, MD (n); Paul Tornetta, III, MD (n);
Cameron Sadeghi, BA (n);
Boston Medical Center, Boston, Massachusetts, USA

Introduction/Purpose: The axillary radiograph is part of the standard shoulder series after injury and is useful in assessing fracture anatomy and glenohumeral joint dislocations. The treatment of surgical neck fractures is based on angulation at the fracture site, including the axillary view. Our hypothesis is that angulation seen on the initial axillary view may not correlate with angulation at union in the lateral plane as the radiograph is taken with the humerus in a position that is different than the treated position. The purpose of this study was to evaluate the correlation of the angulation on initial and healed radiographs of surgical neck fractures treated nonoperatively.

Methods: Over a 5-year period, 252 patients with proximal humerus fractures were treated at our institution. 36 patients with displaced isolated surgical neck fractures that were treated to union nonoperatively and had appropriate radiographs were identified and form the basis of this report. Fracture angulation was measured on the injury and healed anteroposterior, Y, and axillary views. Comparisons were done to determine the ability of the injury films to predict final angulation after healing.

Results: The interclass correlation between the measurements is shown in the table below. In looking at the two representations of lateral angulation, there was moderate agreement between the injury and healed Y views (ICC 0.5, 95%CI: 16-0.73), but only fair correlation between the injury and healed axillary views (ICC 0.35 95% CI: -0.09-0.7). The poorest correlation was seen between the injury axillary and the healed Y view (ICC 0.08 95% CI: -0.1-0.32). This demonstrates the initial axillary view to be a less predictive measure of the lateral angulation at union than the initial Y view. The initial axillary view appears to overestimate the deformity, with an average angulation of 52° resulting in only 32° at union as opposed to the anteroposterior (14.6° to 12.7°) and Y (24° to 23°) views, which were predictive of the position at union.

ICC Between Measured Angles
   Injury Axillary  Final Y  Final Axillary
 Injury Y  0.28 (-0.09-0.59)  0.5 (0.16-0.73)  
 Injury Axillary     0.08 (-0.1-0.32)  0.35 (-0.09-0.7)

Conclusion: Axillary radiographs of surgical neck fractures taken at the time of injury may overestimate the angulation in the lateral plane that will be present if fractures are treated nonoperatively. Previously, more variation in the axillary view has been noted in cadaveric specimens imaged in different rotations. In the clinical setting, however, it is more likely that the position of the arm as it is held for the radiograph allows for varying amounts of angulation that are not consistent with the true lateral angulation when the arm is immobilized at the side (as seen on the Y view). The initial axillary radiograph should not be used to determine treatment of isolated displaced surgical neck fractures. The Y view is more predictive of angulation at union.

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· The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an "off label" use). · · FDA information not available at time of printing.