Type III monteggia injury with ipsilateral type II Salter Harris injury of the distal radius and ulna in a child: a case report

Monteggia fracture patterns are rare in children and merits appropriate treatment to avoid late disability of the elbow and forearm. The injury pattern is easily missed initially or later if not followed up adequately. Both operative and non operative treatment methods are described and are equally successful. The chosen method will be dictated by the injury pattern, associated skeletal injuries and the stability of reduction achieved intra-operatively. We report this rare injury with associated distal radius and ulna injury in the ipsilateral limb, the importance of a full thorough clinical examination and the need for full length radiographs in order not to miss this injury particularly by the junior doctors in the emergency department.

Giovanni Monteggia, based on cadaveric studies, described the pattern of injury in adults but the peak incidence occurs in the age range of 4–10 and represents 0.4% of all forearm fractures[1]. Due to the infrequent exposure of this type of injury it can be easily missed if not specifically looked into.

Bado later classified the injury into 4 subtypes depending on the direction of radial head dislocation[2]. Several variants have been further described particularly in children[3]. Of these injuries, type 1 (59%) and type-III (26%) are the most common[4, 5]. Our patient sustained a type-III injury with an ipsilateral Type II Salter Harris distal radius and ulna fracture.

It has been estimated that, up to 50% senior house officers in accident and emergency departments and 25% of senior radiologists missed a Monteggia injury[6]. Our patient had a painful forearm coupled with restricted elbow and forearm movements, which heightened the suspicion. A good clinical examination of the elbow and forearm is therefore important to rule out this pattern of injury. This may be difficult in an uncooperative child but should be routinely practised. Appropriate full length radiographs are requested when clinical suspicion is high. This we feel goes a long way in identifying the injury and preventing late complications.

Non operative methods of reduction have been reported with successful outcomes[1, 7–11]. These fractures - whether it be plastic deformation or incomplete fractures – tend to be stable and thus maintain the anatomical reduction in a cast achieving good results[1, 5, 7–11].

Operative intervention should be performed for failed closed reduction and in unstable fracture dislocation patterns with excellent results being achieved[6, 11–15]. In our patient, the radial head was unstable after closed reduction and therefore the option of transcapitellar wiring was contemplated. We feel the instability pattern is more pronounced if there is an ipsilateral radius fracture, necessating operative stabilisation.

Percutaneous radial head pinning ensures maintenance of superior radio-ulnar articulation. Though concerns have been raised about the possibility of capitellar damage and subsequent physeal damage, we did not notice this in our limited period of follow up. However this is a possibility and only a prolonged follow up till skeletal maturity will confirm this occurrence. It is therefore important to communicate this to the parents in the consent process. The ulna fracture was aligned well and therefore it was decided to treat the same in a well moulded plaster cast.

Unstable Monteggia fracture dislocation with ipsilateral distal radius fracture although rare is possible in children. The injury being uncommon can be easily missed particularly by junior doctors in the emergency department. The physician should have a low threshold for suspecting these types of injuries when examining children. A good clinical examination and full length radiographs of the forearm are mandatory in all suspected cases.

Written informed consent was obtained from the patient’s legal guardian(s) for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.