Higher nonunion rates with locking plates compared to dynamic compression plates in forearm diaphyseal fractures: a multicenter study.

Background: Dynamic compression plate (DCP) osteosynthesis is the gold standard for treating forearm diaphyseal fractures, providing stability and promoting healing. Locking plates (LPs) are increasingly used in modern fracture management but may increase the risk of nonunion if applied with excessive rigidity and without proper fracture site compression. The purpose of this study is to compare the nonunion rate between LPs and DCPs.

Materials and methods: We conducted a retrospective study by reviewing the medical records and radiographs of 515 patients diagnosed with radial and/or ulnar shaft fractures at three trauma centers between 2014 and 2019. Inclusion criteria were patients treated with locking plates (LPs), locking compression plates (LCPs), or dynamic compression plates (DCPs) who had at least 9 months of outpatient follow-up and imaging assessments. Exclusion criteria included treatment with other methods, hospitalization for pathological fractures or implant removal, or incomplete surgical records. Data on patient demographics, injury details, and surgical outcomes were collected to compare nonunion rates, as well as early and late complications, between the LP and DCP groups.

Results: A total of 368 patients were included in the analysis. Among them, 132 (35.9%) had isolated radial shaft fractures, 116 (31.5%) had isolated ulnar shaft fractures, and 120 (32.6%) had both-bone fractures. Of these, 124 patients received LP implants, 98 were treated with LCPs, and 146 were treated with DCPs. Early complications were comparable among the groups; however, the nonunion rate was significantly higher in the LP group (18.5% versus 11.2% versus 6.2%, p < 0.007). Logistic regression identified LP use [odds ratio (OR): 3.05, 95% confidence interval (CI) 1.24-7.53] as a significant predictor of nonunion. Notably, LPs lacking dynamic compression functionality were associated with markedly higher odds of nonunion in radial shaft fractures (OR: 26.94, 95% CI 3.52-206.15). These findings collectively indicate that LPs increase the nonunion rate in forearm fractures.

Conclusions: Using LPs without compression functionality to treat forearm diaphyseal fractures increases the nonunion rate, particularly in radial shaft fractures. Therefore, we recommend using LCPs or DCPs for forearm diaphyseal fractures to ensure adequate compression at the fracture site during fixation, thereby promoting optimal bone healing rates.

Level of evidence: Level III: retrospective comparative therapeutic study.