Material and Method: All PHILOS-plate osteosynthesis operations for two and three part proximal humeral fractures conducted at Chiang Mai University Hospital between January 2010 and December 2011 were evaluated retrospectively. Operative time, blood loss, mean fracture union time, and rate of axillary nerve injury were recorded for each patient.

Results: The records of twenty-eight consecutive osteosynthesis operations were reviewed and the patients were divided into two groups. Group A included 12 patients (4 males, 8 females, mean age 52 years) who were treated by MIPO. Group B included 16 patients (8 males, 8 females, mean age 62 years), who were treated using the conventional approach. The mean operative time in group A was 80 minutes (range 55-185), and in group B 110 minutes (range 90-180) (p = 0.059). The mean blood loss in group A was 87.5±42.0 ml, and in group B was 128.1±65.8 ml (p = 0.073). The mean length of hospital stay in group A was 5.7±1.7 days, and in group B was 8.4±4.3 days (p = 0.091). The mean fracture union time in group A was 12 weeks (range 10-24), and in group B was 20 weeks (range 12-28) (p = 0.002). Axillary nerve injury rates were not different between the two groups.

Conclusion: Compared to conventional techniques, MIPO offers the advantages of significantly shorter time to union, less blood loss, shorter operative time, and a shorter hospital stay.

Keywords: MIPO, Hospital stay, Blood loss, Operative time, Axillary nerve injury