Surgical treatment of proximal ulna nonunion.

We reviewed our experience in the surgical treatment of 12 cases of proximal ulna nonunion. The primary injuries were 2 fracture-dislocations of the olecranon, 6 Monteggia lesions and 3 isolated fractures of the proximal ulna. According to the type of primary injury and its anatomical site, the nonunions were classified into 2 groups, considering that the nonunions nearest to the humerus-ulna joint present a more disabling clinical profile and are more difficult to treat: group A (6 patients - nonunion within 5 cm from the olecranon tip of the olecranon) and group B (6 patients - nonunion between 5 and 10 cm from the olecranon tip of the olecranon). In all cases, after fibrous callus debridement and bone surface remodelling, fixation was performed with plate and screws and homoplastic cortical bone graft (orthogonal or parallel to the plate) and an intercalary bone cylinder when the bone defect was severe. In 3 patients (group A), where the defect was smaller than 1 cm, fixation of the ulna was combined with a resection of the radial neck. Clinical-radiographic healing was achieved in all patients followed for a mean of 27 months. Complications included a case of nonunion due to failure of the intercalary graft with plate breakage. The patient healed after a new surgery performed with same technique. The score, according to the Broberg-Morrey scoring system, was 78 in group A patients and 93 in group B patients. The use of homoplastic cortical bone graft represents an effective technique to improve the mechanical properties of the fixation and supports biological union, even when the bone defect is severe.