Increasing complexity and plateauing outcomes in AO type C distal humerus fractures: a 50-year institutional case...

Distal humerus fractures in adults are rare but complex injuries, particularly AO type C3 fractures, often involving comminution, instability, and osteoporotic bone. Demographic trends indicate rising incidence, especially among elderly patients, with increasing functional demands challenging modern osteosynthesis. Open reduction and internal fixation (ORIF) with bicolumnar plating remains the preferred reconstructive approach, although complications remain substantial. This study aimed to evaluate trends in fracture complexity, patient demographics, and functional outcomes over five decades, focusing on the most recent cohort (2009-2018, series E) and comparing with historical cohorts (series A-D, 1969-2008).

This retrospective analysis included five consecutive 10-year institutional cohorts (series A: n = 43; B: n = 29; C: n = 47; D: n = 58) of 233 patients with 235 supradiacondylar distal humerus fractures (AO type C1-3) treated with ORIF. Functional outcome parameters (Jupiter and Cassebaum Scores) and demographic data were available for all cohorts; additional parameters (range of motion (ROM), QuickDASH Score) were available for series D and E, Mayo Elbow Performance Score (MEPS), Short Form (SF)-36, and strength were assessed specifically in series E (n = 56; follow-up n = 21). Cross-cohort comparisons of categorical variables used chi-square tests; continuous outcomes were summarized descriptively. Historical cohort means served as a basis for comparison, and analysis of variance (ANOVA) with Tukey Honestly Significant Difference (HSD) was applied for within-series analyses.

Mean patient age increased to 62.6 (range 19-89, SD ± 18.1) years in series E. The proportion of AO type C3 fractures rose significantly from 11.6% (series A) to 71.4% (series E) (p ≤ 0.05). In series E (n = 56, follow-up n = 21), ORIF with bicolumnar plating was performed in 94.6% of cases and the overall complication rate was 16.4%, with mean hospitalization time of 11.1 (range 1-40, SD ± 10.1) days, mean extension deficit of 23° (range 0-90°, SD ± 26.4°), strength loss of 25.5 N (range 0-64.7 N, SD ± 19.1 N), QuickDASH Score of 23.3 (range 0-61.4, SD ± 21.2), and mean MEPS of 83.2 (range 45-100, SD ± 17.0). Good-to-excellent results were observed in 52.6% (Jupiter) and 73.7% (Cassebaum). Subjective satisfaction remained high.

Over five decades, distal humerus fractures increasingly involved older patients and more complex AO type C3 patterns. While ORIF continues to provide satisfactory outcomes, persistent deficits in motion and plateauing functional scores indicate that reconstructive limits may be approached in this evolving patient population.

Level IV; Case series, treatment study.