Is minimally invasive plating osteosynthesis for humeral shaft fracture advantageous compared with the conventional open technique?

The minimally invasive plate osteosynthesis (MIPO) technique has been described and used effectively in humeral shaft fractures. However, the postoperative deformity resulting from malreduction with the minimally invasive technique has not received adequate attention. The purpose of this study was to evaluate the postoperative malrotation and the functional results of the MIPO technique and conventional plating in open reduction and internal fixation after humeral shaft fracture.A prospective cohort research was performed; 53 cases of humeral shaft fractures in a level I trauma center were included and allocated into group I for open reduction and internal fixation or group II for MIPO. Computed tomography was used to measure the postoperative malrotation. The status of the union, functional scoring, and muscle strength were recorded at 12 months after surgery.Both groups exhibited satisfactory union results and final shoulder function scoring. Shoulder girdle musculature of both groups exhibited considerable strength loss with no obvious intergroup discrepancy, with greater internal rotation strength loss compared with external rotation. A significantly increased incidence of postoperative malrotation >20° was observed in the MIPO group (40.9% vs. 0%; P < .01). A linear correlation between postoperative malrotation and range of rotation loss was observed.The MIPO technique might be advantageous as a cosmetic consideration; however, it did not improve postoperative function and strength restoration results more than the open technique. Moreover, MIPO was associated with greater postoperative malrotation, which was considered to be correlated with subsequent long-term shoulder degeneration.