Abstract
Abstract: Monteggia fracture dislocation in an uncommon injury in children. In the less severe injuries, with minimum angulation of the ulnar fracture, the radial head dislocation is frequently missed. The treatment of these late recognised injuries (more than one month) remains controversial, with frequent complications and high failure rates reported in literature.
We have devised a new operative technique which has proved so far to be very successful and reliable. The procedure can be recommended only for children who have no major intra-articular injury, no epiphyseal damage and only mild adaptive changes of the radial head. It is also contraindicated if there is significant overgrowth of the radius as well as secondary changes in the proximal and distal radioulnar joints. The parents are warned of possible complications and residual loss of some movements.
Under general anaesthesia, a curved longitudinal incision is made centred over the ulnar deformity extending proximally to the lateral epicondyle. The essence of the operation is the oblique ulnar metaphyseal osteotomy. The cut is made starting proximal medial to distal lateral. The osteotomy recreates the instability allowing open reduction of the radial head. It also allows for ulnar lengthening by the sliding of the osteotomised surfaces with graft interposition if necessary. The radial head is approached between the anconeus and wrist extensors, through the same exposure. The annular ligament is dividend and radial head reduced into its anatomical position. The ulna is securely fixed in the angulated position using a one third tubular plate. Finally, after checking the stability of the radial head in all forearm movements, the annular ligament is repaired. An above elbow cast is applied with forearm in supination and elbow in 90 degrees of flexion.
The cast is worn for six weeks, with weekly check radiographs. Active use of the arms is encouraged after this with follow up at increasing intervals. The follow up of our cases has shown that the ulnar angulation completely remodels, with normal development of the radial head. A functional range of forearm rotation and full flexion/extension at the elbow are regained with time. We have not noted any residual subluxation/dislocations in our cases.
The abstracts were prepared by Mr Ray Moran. Correspondence should be addressed to him at Irish Orthopaedic Associaton, Secretariat, c/o Cappagh National Orthopaedic Hospital, Finglas, Dublin 11.
