Angular and sliding stable antegrade nailing (Targon PH) for the treatment of proximal humeral fractures

Abstract

Introduction: The optimal surgical treatment for displaced proximal humeral fractures continues to be controversial. Different treatment modalities are available. Mechanical implant-related problems, however, and the preservation of the biological integrity of the humeral head remain unsolved. New implants providing angular stability are expected to maintain the intraoperative result of reduction until definitive healing. The purpose of this study was to evaluate the functional outcome and the complication rate of an angular and sliding stable antegrade interlocking nail for the treatment of displaced proximal humeral fractures.

Materials and methods: In a prospective study, 112 consecutive patients with displaced proximal humeral fractures were treated. Complete 12 months postoperative follow-up was available for 74 patients. Fracture types were classified according to the Neer-classification. Clinical, functional and radiographic follow-up evaluations were performed 3, 6 and 12 months after surgery. The Constant Score (CS) was used to assess shoulder function.

Results: All fractures were united. The CS (MV +/- SD) of the injured side 3, 6 and 12 months after surgery were 42.1 +/- 15.1, 56.1 +/- 20.1 and 70.9 +/- 19.3, respectively. Patients sustaining Neer III and VI/3 fractures revealed better shoulder function (68.8 +/- 14.7, 74.9 +/- 17.6) 12 months postoperatively than those with Neer IV/4 fractures (60.7 +/- 23.2), where most complications occurred. Complications requiring surgical therapy were seen in a total of 24 patients (30%) and included backing out of screws in nails without peak inlay (20%; 2000-2003), protrusion of screws into the gleno-humeral joint (5%), loss of reduction with malunion (9%) and major tubercle displacement (7%).

Conclusion: The treatment of displaced proximal humeral fractures with an angular and sliding stable antegrade nail (Targon-PH) led to good functional results, especially in 2- and 3-part fractures. There exists a substantial risk for postoperative complications and bad motor function in Neer IV/4 fractures. Lateral backing out of screws was abolished by implant modifications (PEEK-inlay) from 2003 onwards. Additional tension wire banding of the major tubercle may further reduce the risk of secondary displacement.