Complications correlate to the severity of the injury. Based on aggregated data from the past 10 years, the total revision surgery rate is nearly 20%, with the top two causes being the removal of hardware and proximal ulnar nonunions (Table 1).[10,34,40–42] Stiffness and HO can be unpredictable in any elbow surgery, but secondary surgery for contracture release is rare.
Type IID Monteggia fractures, with severe comminution and segmental fragmentation of the proximal ulna, have limited bone-to-bone contact with an inadequate reduction. Inherently, these unstable elbows with deforming forces result in more challenging surgery. Accepting suboptimal reduction and fixation frequently leads to nonunion and persistent instability.
The risk of HO is higher with severe soft-tissue trauma and fracture comminution, with reports as high as 20% to 75%.[10,40] In Monteggia fractures, HO generally develops laterally along the collateral ligaments and near the radial neck, which affects both the flexion-extension arc and forearm rotation. Surgical excision and contracture release are typically performed 6 months after the time of the initial surgery but can be expedited in cases of severe ulnar nerve neuropathy from stiff elbow flexion.
The incidence of radioulnar synostosis is unclear because the literature often cites HO and elbow contractures without clearly defining synostoses. In our experience, radioulnar synostosis is rare and more likely to occur with extensive dissection between the ulna and the radius. The development of a synostosis may be more likely with the need for dual plating. The excision of a synostosis is challenging because of posttraumatic scarring, the requirement for deep dissection, and the potential injury to the PIN. However, the outcome is favorable, with satisfactory rotations achieved in most patients.
In one case series, PIN injuries occurred in 6% of patients with Monteggia fractures. Owing to inconsistent follow-up, the recovery of the PIN palsy was unclear. Neurolysis and tendon transfers are both valid options. Avoiding distal dissection, such as what is needed for plating the radial head and neck, is prudent as this increases the risk of PIN injury.
J Am Acad Orthop Surg. 2020;28(19):e839-e848. © 2020 American Academy of Orthopaedic Surgeons