ORIF may be better than hemiarthroplasty for some proximal humerus fractures

Of the six patients who developed AVN, all had less than 2 mm metaphyseal bone on the humeral head.

Research indicates a significant clinical benefit with open reduction and internal fixation compared to hemiarthroplasty for patients with three- and four-part proximal humerus fractures with initial valgus fracture patterns, but shows no advantage to the procedure for those with varus fractures or less than 2 mm of metaphyseal hinge.

In a retrospective review of patients treated for three- and four-part proximal humerus fractures, Brian D. Solberg, MD, and colleagues compared the outcomes of 40 patients who underwent open reduction and internal fixation (ORIF) to an a group of 40 patients who had hemiarthroplasty and were matched to the ORIF cohort for age, gender and comorbidity. All of the patients were older than 55 years and had at least 24 months of clinical and radiographic follow-up.

Clinical results

The investigators discovered significantly better Constant scores in patients with three-part proximal humerus fractures who were treated with ORIF compared to those who had hemiarthroplasty. However, they found no significant differences in the Constant scores between the treatment groups regarding patients with four-part fractures.

They also found that patients with an initial malreduction of less than 5° had significantly better Constant scores than those with fair (5° to 15°) or poor (15° to 20°) initial malreductions.

In addition, the investigators discovered patients with initial valgus fracture patterns who underwent ORIF had significantly better Constant scores than those who had a hemiarthroplasty. However, they found no significant differences in the scores between the ORIF- and hemiarthroplasty-treated groups if there was a varus fracture pattern, or the patient developed avascular necrosis (AVN). Six patients developed AVN and all had less than 2 mm of metaphyseal bone attached to the humeral head.

A comparison of patients who met the criteria for having a good result with ORIF to those who met the criteria for having a good result with hemiarthroplasty revealed significantly better Constant scores in the ORIF group.

“These older patients have a significant complication rate, and AVN is likely if the humeral head has less than 2 mm of metaphyseal bone attached to the head,” Solberg said during his presentation at the 24th Annual Meeting of the Orthopaedic Trauma Association. “ORIF with locked plating seems to have a clear benefit over hemi in valgus fracture patterns regardless of the end fracture site, but there does not appear to be a benefit in varus fractures or if there is less than 2 mm of metaphyseal hinge.”

Limitations

The investigators found that four patients in the ORIF group had a loss of fixation, and all had a malreduction greater than 20°. In addition, six patients had head perforation. This occurred early in three cases and late in the remaining three.

“Hemiarthroplasty outcomes were mostly influenced by humeral head height and calcar offset, which were probably related,” Solberg said. “But, tuberosity displacement did not seem to have an impact.” Six patients in the group developed tuberosity nonunion.

Solberg cited the retrospective nature of the study, intra-observer disagreement regarding fracture classification and lack of DEXA scans as limitations. He also noted that the intent-to-treat protocol called for surgeons to attempt ORIF first, unless there were confounding factors. This may have led to selection bias, he said.

For more information:
Brian D. Solberg, MD, can be reached at 444 South San Vicente Blvd, Suite 603, Los Angeles, CA 90048; 310-423-9954; e-mail: brian.solberg@cshs.org. He is a consultant for Stryker and Zimmer.

Reference:
Solberg BD, Moon CN, Franco DP, et al. Clinical outcomes of three-and four-part proximal humerus fractures: Open reduction and internal fixation versus hemiarthroplasty. Paper #35. Presented at the 24th Annual Meeting of the Orthopaedic Trauma Association. Oct. 16-18, 2008. Denver.