Lessons learned from treating patients with unstable multifragmentary fractures of the proximal humerus by minimal invasive plate osteosynthesis.

Introduction: The authors present clinical and radiographic results of minimal invasive plate osteosynthesis (MIPO) for three- or four-part fractures of the proximal humerus.

Patients And Methods: Twenty-six patients with three- or four-part proximal humeral fractures treated with the MIPO technique through the deltoid splitting approach were clinically and radiographically evaluated at a minimum of 12 months with an average of 20.1 months. The valgus-impacted type of three-part fracture was excluded to verify the results of the MIPO with unstable multifragmentary fractures of the proximal humerus.

Results: Twenty female patients and six male patients were included (mean age 67 years; range 18-90 years). No cases of nonunion were seen. The mean forward flexion, abduction, and external rotation were 145°, 119°, and 48°, respectively. The mean visual analog scale (VAS) for pain was 1.47 points. The mean Disabilities of the Arm, Shoulder, and Hand (DASH) score was 14.5 points, and the mean UCLA score was 29.6 points. The mean neck-shaft angle was 134°. Twenty-three patients had adequate medial support, and three patients did not have adequate medial support on initial postoperative radiographs. Five shoulders (19 %) developed complicated results. Two cases of proximal malposition of the plate (7.7 %) and two intra-articular screw penetrations (7.7 %) were observed. One case of osteonecrosis of the humeral head was identified at the final follow-up (3.8 %).

Conclusion: The MIPO technique provides reliable radiologic and functional outcomes for three- and four-part proximal humeral fractures. Our results might support the use of MIPO for treating unstable multi fragmentary fractures of proximal humerus such as three- or four-part fractures to decrease osteonecrosis of humeral head.