Comparison between minimally invasive, percutaneous osteosynthesis and locking plate osteosynthesis in 3-and 4-part proximal humerus fractures.

Background: The ideal method for the surgical treatment of proximal humeral fractures has not yet been found. We therefore conducted a retrospective matched-pair analysis and compared osteosynthesis with open reduction and internal fixation and that with an angular stable plate with minimally invasive, closed reduction, percutaneous fixation with the Humerusblock.
Methods: During a study period of 3 years, we matched 30 patients treated with angular stable plates (group 1) for age, gender, fracture type and handedness (dominant or nondominant) to 30 patients treated using the Humerusblock (group 2). At a minimal follow-up of 24 months, clinical evaluation included the Constant-Murley score, the UCLA score and the Simple Shoulder Test. Subjective pain was evaluated using the VAS pain scale. Patients were asked to rate their subjective satisfaction of final outcome as excellent, good, satisfied or dissatisfied.
Results: The mean CMS, UCLA score and SST differed significantly between groups 1 and 2 (60.9 vs 71.9, p < 0.01), (25.1 vs 29.5, p < 0.01) and (8.1 vs 9.4, p < 0.05), respectively. The VAS pain score was significantly lower in group 2 than in group 1 (1.2 vs 2.4; p < 0.01). The mean abduction (109.7° vs 133.7°; p < 0.01) and anterior flexion (128.3° vs 145.7°; p < 0.01) were significantly worse in group 1. The mean operation time was significantly shorter in group 2 (117.3 vs 72.1, p < 0.01). Complications occurred in 30 % (group 1) and 23 % (group 2) of patients.
Conclusions: In this study, the functional outcome is superior in the Humerusblock group. However, the general outcome after surgical treatment of 3-and 4-part fractures is moderate, and the complication rate has to be considered, even though it can be lowered with the use of minimally invasive implants.