Proximal humeral fractures consist of 4-5% of all the fractures in human body and make up 80% of all humeral fractures.Most of these fractures results from minor trauma in old age and high velocity injury in younger.Different operative treatment modalities are available for this fracture. TheProximal Humeral Internal Locking System plate (PHILOS plate) is an internal fixation system that helps in angular stability, reduce vascular compromise and improve fixation in osteoporotic. This study was performed to evaluate the functional outcome in proximal humerus fractures treatedwithPHILOS plating. METHODS:Aprospective observational study conducted from July2018 to Aug 2019 inNational trauma center, Bir hospital Nepal. 41 patients fulfilling the criteria were enrolled in the study and treated with open reduction and internal fixation with PHILOS plate and the outcome assessed using Constant Murley scoreat 6 weeks, 3 months and 6 monthsfollow up. The collected data were analyzed using Fisher exact test. RESULT:The outcome in this study was good in 58.5%, fair in 24.4%, poor in 9.8% and excellent in 7.3% of the cases with mean Murley Score 80.1±6.1SD. 65.9% patients had good to excellent outcome and 97.6 % patients had achieved clinical and radiological union at 6 month. CONCLUSIONS:Majority of the patients had good to excellent outcome with almost all had radiological union at six month periods. Open reduction and internal fixation with the PHILOS plate provides high degree of angular and axial stability and prevent fixation failure and thus helps in early joint mobilization and returns to functional activity.

Keywords : constant murley score;PHILOS plate;proximal humerus fracture.