Operative and Nonoperative Treatment of Humeral Shaft Fractures

Fractures of the humeral diaphysis occur in a bimodal distribution and represent 3-5% of all fractures. Overall the incidence is higher in women and typically presents at a more advanced age in this population, rendering fixation more difficult due to osteoporosis. The majority of fractures of the humeral diaphysis occur in the mid-shaft and proximal third and the majority are simple (or non-comminuted) in pattern.

Presently, the standard treatment of isolated humeral diaphysis fractures is nonoperative care using splints, braces, casts and slings. Most centres in North America and Europe favor functional bracing with a coaptation splint given the positive results reported with this device, despite the prolonged period of pain and discomfort as well as the need for repeated clinic follow-up visits associated with it.

Presently there are no published prospective comparative studies that systematically evaluate patient function following the operative or nonoperative treatment of humeral shaft fractures.

Clinical evaluations following functional bracing using patient-based outcome tools revealed a 20% nonunion rate in patients suffering a simple (non-comminuted) fracture. Invariably, this led to surgical intervention to achieve union. In those whose fracture healed with the splint, only 50% reported a full recovery while none of those requiring surgery for nonunion did so. This low rate of functional recovery may be due in part to the high rate of shoulder stiffness following functional bracing. Significant stiffness in the shoulder following functional bracing has ranged from 14-60% with an average of 40%.

The advantages of open reduction and plate fixation of humeral shaft fractures include a direct approach to the fracture site with direct visualization and protection of the radial nerve (depending on fracture level and approach), the possibility of rigid compressive fixation, and the opportunity for bone grafting and/or radial nerve exploration if needed. Importantly, it permits rapid mobilization of the shoulder and elbow, obviating the need of immobilization, and ensures anatomic or near anatomic alignment. These advantages must be weighed against the small risk of infection (<1-6%) with most occurring after open fractures or severe crush injury, nonunion (4-6%) especially in high energy injuries, and iatrogenic radial nerve injury (1-3%) the vast majority of which are transient.

Operative care: Fixation with regular or broad 3.5mm or 4.5mm dynamic compression plate (DCP) using standard technique will be applied in cases with normal bone density; in the face of osteopenic bone, locked-plate implants will be employed at the discretion of the surgeon. Bone graft will not be used routinely as these are simple fracture patterns. Postoperative splinting (or sling) will be maintained for 10 - 14 days followed by gentle ROM exercises under physiotherapy supervision. Strengthening and proprioception will be begun once fracture healing has occurred, typically at 6-8 weeks.

Conservative care will entail the application of a plaster sugartong splint for 10-14 days followed by transition to a functional (coaptation) brace, to be applied by a qualified orthotist. Gentle ROM exercises of the elbow and shoulder will begin as tolerated under the supervision of a physiotherapist after 2 weeks with strengthening and proprioception added once fracture healing has occurred, typically at 6-8 weeks.

This multicentre prospective randomized trial will involve the Canadian Orthopaedic Trauma Society (COTS), an association of trauma surgeons involved in collaborative outcomes research with a proven track record of research and publication. Patients with a humeral diaphyseal fracture who meet all eligibility criteria and provide consent to participate will be randomly assigned to the operative or splint/brace treatment group. Patients will start physiotherapy at 2 weeks post-randomization (splint/brace group)or 2 weeks post-surgery for gentle ROM exercises. The operative group will progress to strengthening and proprioception at 4-6 weeks. The splint/brace group will only progress at the 6-8 weeks mark once union has occurred. Evaluation at 2 and 6 weeks, 4, 6, and 12 months will include functional, clinical and radiological parameters. Functional evaluation will include the DASH, SMFA questionnaires and the Constant Shoulder Score. Clinical outcome will evaluate range and motion including the shoulder and elbow of both the affected arm and contralateral shoulder and elbow. Standard radiographic parameters will be measured. The primary outcome measure will be functional outcome as measured with the DASH. Appropriate statistical analyses will be performed on the data. Sample size calculation reveals the need for 90 patients per treatment arm. A census of the centers committed to the study predicts a 1-24 month recruitment period. Patient follow-up will end at the 12 month visit.