Monteggia fracture dislocation equivalents--analysis of eighteen cases treated by open reduction and internal fixation.

OBJECTIVE: Monteggia fracture dislocation equivalent, though already described by Bado, is still an unclassified entity. We aimed to retrospectively analyze 18 cases of Monteggia variants and discuss the injury mechanisms, management, and outcome along with a review of the literature.

METHODS: A retrospective record of Monteggia fracture dislocation (2003-2008) was reviewed from medical record department of our institute. Classic Monteggia fracture dislocation, children below 12 years or adults over 50 years, as well as open grade II and III cases were excluded from this study. Monteggia variant inclusion criteria included fracture of the proximal ulna together with a fracture of the radial head or neck and skeletal maturity. Totally 26 patients were identified with Monteggia variants and 18 were available for follow-up, including 11 males and 7 females with the mean age of 35 years. The ulna fracture was treated by compression plating along with tension band wiring. Radial head/neck was reconstructed in 12 patients while excised in 6 patients.

RESULTS: Follow-up ranged from 1-4 years, mean 2.6 years. Patients were assessed clinicoradiologically. Mayo Elbow Performance Score was employed to assess the outcomes. At final follow-up, the results were excellent in 10 patients, good in 4, fair in 2 and poor in 2. Mean range of motion of the elbow was 20 degree 116 degree, 50 degree and 55 degree for extension, flexion, pronation and supination, respectively. Two patients had complications in the form of heterotopic ossification and stiffness of the elbow. One nonunion ulna, primarily treated by tension band wiring, was managed by refixation with locking reconstruction plate and bone grafting. Bone grafting was only required in this patient for nonunion. Another patient had implants removed on his request. The results in our series closely correlated with extent of intraarticular damage, coronoid fracture and comminuted fractures.

CONCLUSIONS: Monteggia fracture dislocation equivalents are rare injuries and pre-surgery recognition by radiographs and 3-D CT helps make optimal plan. The poor results usually relate to intraarticular damage, coronoid fractures and comminution of the ulna and radial head fractures.