Small-Fragment Plate Fixation of Humeral Shaft Fractures.

Fixation of humeral shaft fractures is frequently performed with large-fragment (4.5 mm) plates to accommodate immediate weight bearing. Use of small-fragment (3.5 mm) plates as an alternative carries theoretical benefits. We examined nonunion rates and postoperative radial nerve palsy (RNP) rates in a retrospective cohort of patients undergoing open reduction and internal fixation of humeral shaft fractures with 3.5-mm or 4.5-mm plates. Two hundred thirty-six patients with 241 humeral shaft fractures were included. Small 3.5-mm plates were used in 83% of the patients, and large 4.5-mm plates were used in 17% of the patients. Fifty-three percent were made weight bearing as tolerated following surgical fixation. There was a 7% incidence of nonunion and a 10% incidence of RNP in the 3.5-mm plate group. There was a 7% incidence of nonunion and a 15% incidence of RNP in the 4.5-mm plate group. No statistically significant relationship was shown between nonunion or RNP and plate size (P=.74 and P=.39). No relationship was shown between nonunion and postoperative weight-bearing status (P=.45). Subgroup analysis according to plate size additionally showed no association of nonunion with postoperative weight bearing in both the 4.5-mm (P=.55) and the 3.5-mm (P=.25) cohorts. Small-fragment and large-fragment plating of humeral shaft fractures resulted in comparable union and RNP rates, regardless of postoperative weight-bearing status. Our findings suggest that 3.5-mm plate fixation of humeral shaft fractures is a safe alternative to 4.5-mm plate fixation. [Orthopedics. 2023;46(4):198-204.].

Digital blinding of radiographs to mask allocation in a randomized control trial.

AIM: To demonstrate the effectiveness of a digital radiographic altering technique in concealing treatment allocation to blind outcome assessment of distal femur fracture fixation. METHODS: Digital postoperative anteroposterior and lateral radiographs from a sample of 33 randomly-selected patients with extra-articular distal femur fractures treated by surgical fixation at a Level 1 trauma center were included. Using commercially available digital altering software, we devised a technique to blind the radiographs by overlaying black boxes over the implant hardware while preserving an exposed fracture site for assessment of fracture healing. Three fellowship-trained surgeons evaluated a set of blinded radiographs twice and a control set of unblinded radiographs once. Each set of radiographs were reviewed independently and in a randomly-assigned order. The degrees of agreement and disagreement among evaluators in identifying implant type while reviewing both blinded and unblinded radiographs were assessed using the Bang Blinding Index and James Blinding Index. The degree of agreement in fracture union was assessed using kappa statistics. RESULTS: The assessment of blinded radiographs with both the Bang Blinding Index (BBI) and James Blinding Index (JBI) demonstrated a low degree of evaluator success at identifying implant type (Mean BBI, far cortical locking: -0.03, SD: 0.04; Mean BBI, standard screw: 0, SD: 0; JBI: 0.98, SD: 0), suggesting near perfect blinding. The assessment of unblinded radiographs with both blinding indices demonstrated a high degree of evaluator success at identifying implant type (Mean BBI, far cortical locking: 0.89, SD: 0.19; Mean BBI, standard screw: 0.87, SD: 0.04; JBI: 0.26, SD: 0.12), as expected. There was moderate agreement with regard to assessment of fracture union among the evaluators in both the blinded (Kappa: 0.38, 95%CI: 0.25-0.52) and unblinded (Kappa: 0.35, 95%CI: 0.25-0.45) arms of the study. There was no statistically significant difference in fracture union agreement between the blinded and unblinded groups. CONCLUSION: The digital blinding technique successfully masked the surgeons to the type of implant used for surgical treatment of distal femur fractures but did not interfere with the surgeons' ability to reliably evaluate radiographic healing at the fracture site.