Rare Presentation of a Type I Monteggia Fracture V K Peter

CASE REPORT Emerg Med J: first published as 10.1136/emj.19.1.88 on 1 January 2002. Downloaded from Rare presentation of a type I Monteggia fracture V K Peter ......

Emerg Med J 2002;19:88–89

DISCUSSION A rare case is reported of a Monteggia equivalent injury Any dislocation of the radial head with an ulnar fracture con- where a dislocation of the radial head is associated with stitutes a Monteggia lesion. Of the various classifications fracture of the distal third of the radius and ulna. The available, Bado’s is the one that is almost universally in use. mechanism, treatment and outcome are described. Type I: anterior dislocation of the radial head, fracture of the ulnar diaphysis at any level with anterior (volar) angulation. Type II: posterior or posterolateral dislocation of the radial head, fracture of the ulnar diaphysis with posterior (dorsal) CASE REPORT angulation. 12 year old boy fell backwards off a chair onto his Type III: lateral or anterolateral dislocation of the radial outstretched left arm. He described a twisting injury to head with fracture of the ulnar metaphysis or diaphysis. Athe arm at the time. He was seen in the accident and Type IV: anterior dislocation of the radial head, fracture emergency department with an obvious deformity of the dis- proximal third radius and fracture of the ulna at the same tal forearm and tenderness over the ipsilateral elbow. level.1 Movements at the wrist and elbow were painful and Letts classified such fractures in children into five groups. A restricted, and no neurological or vascular deficits were noted. (plastic deformation of the ulna), B (green stick fracture) and Radiographs showed a fracture of the distal third of the radius C (complete fracture) are essentially variations of a Bado I with a plastic deformation of the ulna at a point just distal to lesion. D and E correspond to type II and type III respectively. the site of the radial fracture. Both bones were angulated He considered Bado IV to be a type I variant.2 volar-wards. At the elbow the radial head was dislocated ante- Other type I variants include isolated anterior dislocation of riorly (fig 1). the radial head, fracture of the ulnar diaphysis with fracture of A closed reduction of the fracture was accomplished under a general anaesthetic. On reduction of the forearm fracture and supinating the forearm, the radial head relocated itself without difficulty (fig 2). An above elbow cast was applied and the child followed up with weekly radiography for four weeks, http://emj.bmj.com/ at which stage the plaster was removed. At his last review eight weeks after injury, he had excellent wrist and elbow movement, with full range of pronation and supination. on September 28, 2021 by guest. Protected copyright.

Figure 2 Radiographs after reduction: a good position of the Figure 1 Initial radiographs showing the dislocated radial head forearm bones has been achieved by closed reduction and the radial with distal third bone forearm fractures. head is reduced back in place.

www.emjonline.com Type I Monteggia fracture 89 the neck or proximal radius, associated olecrenon fractures, We would like to emphasise that the mechanism of injury Emerg Med J: first published as 10.1136/emj.19.1.88 on 1 January 2002. Downloaded from distal epiphyseal facture of the radius, etc, all of which occur needs to be taken into consideration at all times. With an after a hyperpronation injury. obviously angulated distal third injury, the features of a dislo- Some variants have also been described for type II, III and cated radial head tend to be masked and very easily missed, IV injuries too.3–5 unless the possibility is considered. The universal principle of In type I Monteggia fractures, the child falls forward on his examining one joint above and below and including both outstretched hand, the forearm is in pronation, and at the when taking radiographs for suspected long bone fractures moment of the fall the hand remains ﬁrm to the ground. A must not be forgotten. moment before the end of the fall, a rotational force is added This patient has gone on to achieve an excellent result. from the trunk; this force causes further external rotation to an arm already in full pronation. As the hand is ﬁxed it causes a fracture of the ulna shaft. At the same time the radius, being ...... forced into extreme pronation crosses the ulna at the junction Authors’ affiliations of the middle and proximal thirds. This contact acts as a V K Peter, Department of Orthopaedics, Royal Liverpool Children’s Hospital, Liverpool, UK fulcrum, forcing the radius to dislocate anteriorly or fracture or both.1 Correspondence to: Type I Monteggia fractures with distal radial and ulnar Mr Peter, 32 Clumber Street, Off Princes Avenue, Hull HU5 3RL, UK; fractures are extremely rare. Blasier et al6 described a similar [email protected] case where the radial head dislocation was initially missed and Accepted for publication 22 June 2001 required a delayed reconstruction of the annular ligament. Most of the other cases of distal radial fractures that have been REFERENCES described in association with a Monteggia lesion are type II 1 Bado JL. The Monteggia lesion. Clin Orthop 1960;60:71–86. 37 injuries. 2 Letts M, Locht R, Wiens J. Monteggia fracture dislocation in children. J In this particular case the radius and ulna were angulated Bone Joint Surg Br 1985;67:724–7. 3 Kristiansen B, Eriksen AF. Simultaneous type II Monteggia lesion and anteriorly with an anterior dislocation of the radial head. The fracture separation of the lower radial epiphysis. Injury 1986;17:51–2. mechanism of injury in this case is most likely to be a hyper- 4 Biyani A. Ipsilateral Monteggia equivalent injury and distal radial and pronation stress to the forearm at the time of the fall. ulnar fractures in a child. J Orthop Trauma 1994;8:431–3. Excellent stable reduction was achieved by conservative 5 Bhandari N, Jindal P. Monteggia lesion in a child: variant of a Bado type IV lesion. A case report. J Bone Joint Surg Am 1996;78:1252–5. means. It is important to restore normal length and achieve an 6 Blasier RD, Trussell A. Ipsilateral radial head dislocation and distal anatomical alignment of the forearm bones, as otherwise the forearm fractures of both forearm bones in a child. Am J Orthop radial head will not reduce back into place. If good reduction 1995;24:498–500. 7 Arazi M, Ogun TC, Kapicioglu MIS. The Monteggia lesion and cannot be obtained closed, the threshold for open reduction ipsilateral supracondylar humerus and distal radial fractures. J Orthop must be very low. Trauma 1999;13:60–3. http://emj.bmj.com/ on September 28, 2021 by guest. Protected copyright.