Session XII - Upper Extremity

Sat., 10/7/06 Upper Extremity, Paper #67, 3:12 pm

Fracture Displacement and Hardware Migration after Open Reduction and Internal Fixation of Proximal Humerus Fractures

Kevin C. Owsley, MD (n); John T. Gorczyca, MD (n);
University of Rochester-Strong Memorial Hospital, Rochester, New York, USA

Introduction: In this retrospective study we evaluate the incidence of fracture displacement and hardware migration after open reduction and internal fixation (ORIF) of proximal humerus fractures using different methods of stabilization.

Methods: Chart and radiographic reviews were performed for patients with displaced proximal humerus fractures treated with ORIF between 2000 and 2005 at a university-based regional trauma center. The operations were performed by a single surgeon using one of several fixation techniques, according to the fracture type and implant availability. Patients older than 16 years and with radiographic evidence of fracture healing or with 1-year follow-up were included in the study. Medical records were reviewed for patient demographic data, past medical history, mechanism of injury, concomitant injuries, dates of injury and surgery, and perioperative complications. Radiographs were analyzed to determine fracture type (AO/OTA), postoperative fracture alignment and hardware position, healing time, and final fracture alignment and hardware position.

Results: 75 proximal humerus fractures were identified in 75 patients with an average age of 51 years (range, 16-89). There were 21 male (28%) and 54 female (72%) patients with fractures classified (AO/OTA) as 20 (27%) type A, 46 (61%) type B, and 9 (12 %) type C. The fractures were stabilized with either locking proximal humeral plates (n = 52), angled blade plates (n = 17), nonlocking T-plates (n = 4), or tension band sutures (n = 2). All but one of these fractures went on to union (99%). 54 fractures (72%) healed within 4 months, while all but one fracture went on to complete union (99%) within 6 months. "Varus collapse" occurred in 15 (20%) of the cases and was evident on multiple radiographic measurements, including a change in humeral head-neck angles (average 8°), change in greater tuberosity to humeral head height difference (average 6 mm), and migration of hardware within the humeral head (average 1.7 mm). Hardware cut-through and/or loss of reduction was noted in 13 (17%) cases. Revision surgery performed in 6 (8%) cases: 3 (4%) had removal of hardware, 1 (1%) had hardware exchange, and 2 (3%) had hemiarthroplasty. There was one patient with osteonecrosis at 1 year; this was also the only case of nonunion. There were no infections or neurovascular complications.

Discussion/Conclusion: Despite recent advances of locked-plate technology, hardware cut-through and loss of reduction after ORIF of proximal humerus fractures remains a problem. These problems are most evident in the geriatric patients and in the more complex 3- and 4-part fractures. Correlating radiographic findings with clinical results remains a challenge. We found that true AP views of the shoulder provide the best detail for serial postoperative radiographic analysis. We also found that following greater tuberosity to humeral head height difference is a sensitive measurement predictive of fixation failure. Further follow-up will be necessary to determine the impact on clinical outcomes.

If noted, the author indicates something of value received. The codes are identified as a-research or institutional support; b-miscellaneous funding; c-royalties; d-stock options; e-consultant or employee; n-no conflicts disclosed, and *disclosure not available at time of printing.
· 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.