Comparison of lateral approach versus anterolateral approach with Herbert screw fixation for isolated coronal shear fractures of humeral capitellum

BACKGROUND: For coronal shear fractures of humeral capitellum, the lateral approach is the most commonly used surgical approach. However, exposure range of the anterior aspect of the distal humerus is inadequate. The anterolateral approach has also been adopted to overcome this disadvantage. However, this approach seems anatomically complex due to the risk of iatrogenic injury to the radial nerve. So far, the optimal approach for the treatment of capitellar shear fractures remains inconclusive. The purpose of this study is to prospectively review and compare the early clinical and radiographic outcomes of treated with open reduction and Herbert screw internal fixation through the lateral approach or the anterolateral approach. METHODS: Twenty-six patients with isolated capitellar shear fractures were enrolled from January 2013 to December 2017, and randomly assigned to lateral approach group or anterolateral approach group. All the fractures were treated with open reduction and Herbert screw internal fixation through lateral approach or anterolateral approach. Operation time, wound healing complication, elbow joint function, and radiographic evidence were evaluated and compared between two groups. RESULTS: The operation via the anterolateral approach took significantly shorter time than via lateral approach (p < 0.05). There were no wound healing problems and infection for both groups. One patient from anterolateral approach group sustained incomplete posterior interosseous nerve palsy, which recovered completely in 4 weeks without residual compromise. All fractures healed well in their normal anatomic position as seen on radiographs. At the final follow-up, no significant difference was found between two groups with respect to the ROM in supination-pronation, ROM in pronation-supination, loss of flexion-extension motion, or loss of pronation-supination motion (p > 0.05). There is no significant difference with respect to MEPI score of elbow joint between two groups (p > 0.05). CONCLUSION: Based on our findings, both lateral approach and anterolateral approach with Herbert screw internal fixation are suitable for coronal shear fractures of capitellum with satisfactory early outcomes. Compared with the lateral approach, the anterolateral approach made the surgical procedure easier and time saving in current series. When the medial aspect of the trochlea is involved for capitellar coronal fractures, the anterolateral lateral approach should be preferred.