Comparison between open reduction and internal fixation and minimally invasive plate osteosynthesis for unstable proximal humerus fractures treated with locking plate and intramedullary allograft: a retrospective study

Abstract

Abstract Background The aim of this study was to compare the functional and radiological outcomes between open reduction and internal fixation (ORIF) and minimally invasive plate osteosynthesis (MIPO) with locking plate (LP) and intramedullary graft (IMG) for treatment of unstable proximal humerus fractures (PHFs). Methods Forty-seven patients with PHFs were treated with ORIF and MIPO techniques in 25 and 22 cases, respectively, and evaluated retrospectively with a minimum follow-up of 12 months. Thirty-one fresh-frozen fibulae and 16 lyophilized tibiae allografts were used for augmentation. Radiological evaluation included the change in neck-shaft angle (NSA) and humeral head height (HHH). Functional outcomes were assessed using DASH and absolute Constant-Murley Score (CSabs) with its derivatives: relative (CSrel) and individual relative (CSindiv). Results Mean follow-up period was 27.4 ± 16.2 months for ORIF and 29.6 ± 17.6 for MIPO group. Mean age was 60.5 ± 13.7 and 66.3 ± 11.7 years for ORIF and MIPO group, respectively. Functional outcomes showed insignificant difference between the groups: CSabs of 57.3 ± 21.2 in ORIF and 52.4 ± 18.9 in MIPO group, (p = 0.409); CSrel of 73 ± 24.1 in ORIF and 73.9 ± 23.4 in MIPO, (p = 0.897); CSindiv of 69.6 ± 24.8 in ORIF and 64 ± 25.5 in MIPO, (p = 0.428); DASH of 14.8 ± 12.5 in ORIF and 18.7 ± 14.5 in MIPO, (p = 0.324). There were no significant differences in radiological outcomes between the two groups: decrease of NSA was 7.8° ± 9.4° in ORIF and 8.2° ± 15.6° in MIPO, (p = 0.922). Decrease of HHH was 0.6 mm ± 5.5 mm in ORIF and 1.4 mm ± 2.6 mm in MIPO, (p = 0.380). Surgical time was 165.8 ± 77.6 min for ORIF and 84.7 ± 38.1 min for MIPO, with significant difference between the groups (p < 0.001). Most common complication was AVN, occurring in five (20%) and 8 (36%) patients in ORIF and MIPO groups, respectively. Conclusions The study found that using LP fixation and IMG augmentation to treat unstable PHFs resulted in similar functional and radiological outcomes between the ORIF and MIPO techniques. However, the MIPO technique had a significantly shorter surgical time compared to ORIF. Trial registration The study was conducted in line with the principles of the Declaration of Helsinki as well as national legal and regulatory requirements. The trial was retrospectively registered and approval was granted by the local Ethics Committee of University Multiprofile Hospital for Active Treatment and Emergency Medicine “N. I. Pirogov”, Sofia, Bulgaria: (No. EC – 01/26.01.2023).