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Isolated traumatic anterior dislocation of the radial head—a mechanism of injury in children
182 Injury (1986) 17,182-183
Printedin Great Britain
Isolated traumatic anterior dislocation of the radial head-a mechanism of injury in children David Stanley Orthopaedic
Department,
Sheffield
Children’s
Hospital
INTRODUCTION TRAUMATICdislocation of the radial head occurring without a fracture of the ulna is a rare injury. It was first described by Duverney in 1751, and since that time several authors have described both the possible mechanism and management of such an injury (Stelling and Cote, 1956; Vesely, 1967; Lloyd-Roberts and Bucknill, 1977). A girl with such an injury is presented
here and a previously undescribed injury is proposed.
mechanism for the
CASE REPORT A 12-year-old girl had been riding her bicycle when she stopped suddenly and went over the handlebars. She remembered putting her left arm out straight to break her fall. Following the accident she had pain in her elbow preventing movement, and for this reason she came to Casualty. On examination the arm was held flexed at 90” with 10” of flexion and extension from this position. Pain prevented further flexion, extension and rotation. There was very little swelling at the elbow and no neurovascular complication. General physical examination revealed hyperextension of her right elbow, but no other features of abnormal joint laxity. Radiographs showed an anterior dislocation of the radial head without fracture of the ulna (Fig. 1). The dislocation was reduced under general anaesthesia by extension of the elbow followed by flexion with pressure over the radial head (Fig. 2). Reduction was held using a collar and cuff for 3 weeks before a slow resumption of activity was allowed.
DISCUSSION Vesely (1967) suggested that a fall occurring when the entire body weight was caught on the outstretched pronated hand would result in dislocation of the radial
Fig. 2. Lateral radiograph of the same elbow after reduction under general anaesthesia.
head. He thought that this was particularly likely if the force was presented at the annular ligament. Wiley et al. (1974), studying the mechanism of injury using the elbows of corpses, found that anterior dislocation could be produced only with difficulty. To achieve this injury they needed to have the forearm in extreme supination, sever completely the anterior capsule and annular ligament and apply force in an anterior direction to the posterior aspect of the radial head. Even when these conditions were met, anterior dislocation could not be produced without considerable force and without extensive disruption of the annular ligament. In some cases tearing of the upper part of the interosseous membrane occurred before the dislocation could be achieved.
Fig. 1. Lateral radiograph of elbow of 12-year-old girl after injury. The isolated anterior radial head dislocation is shown.
Stanley: Radial head dislocation in children
Fig, 3. Photographs
of the patient’s uninjured
183
arm to show the degree of hyperextension
Although this demonstrates the difficulty of experimental production of an anterior dislocation of the radial head, it does not fit with the clinical presentation of this patient. In part this may be due to differences between living and cadaveric tissue, but age may also be important. Illingworth (1975) showed the ‘pulled elbow’ to be an injury of childhood occurring when the head of the radius was pulled partially through the annular ligament. It is suggested that traumatic, isolated dislocation of the radial head occurring in children may result in part from the forces applied at the elbow, but also from anatomical features of development associated with lax ligaments and allowing hyperextension of the elbow (Fig. 3). In hyperextension of the elbow the radial head may be at risk of displacement either partially through the annular ligament or more anteriorly in a lax annular ligament. If force is now applied down the shaft of the radius as would occur in a fall on the extended outstretched arm, the annular ligament would be disrupted allowing the radial head to be dislocated anteriorly. This is proposed as the mechanism of injury in the case presented, and as a possible mechanism in other children who sustain similar injury.
possible at the elbow joint.
Mr R. H. Baker for allowing me to present his patient. I also thank the Photographic Department at Sheffield Children’s Hospital for preparing the illustrations and Mrs M. E. Leeming for typing the manuscript.
REFERENCES
Duverney J. G. (1751) Traitk des maladies des OS. Paris: De Dure L’Aine. Illingworth Cynthia M. (1975) Pulled elbow: a study of 100 patients. Br. Med. J. 2, 672. Lloyd-Roberts G. C. and Bucknill T. M. (1977) Anterior dislocation of the radial head in children. J. Bone Joint Surg. 59B, 402. Stelling F. H. and Cote R. H. (1956) Traumatic dislocation of head of radius in children. JAMA 160, 732. Vesely D. G. (1967) Isolated traumatic dislocation of the radial head in children. Clin. Orthop. 50, 31. Wiley J. J., Pegington J. and Horwich J. P. (1974) Traumatic dislocation of the radius at the elbow. J. Bone Joint Surg. 56B, 501. Paper accepted 11 September
1985.
Acknowledgements I would like to thank Mr T. W. D. Smith and Mr M. J.
Bell for their help in preparation
of this manuscript and
Reyuem for reyrinfs should he addressed IO: D. Stanley, 7 Stumperlowe Park Road,
Fulwood,
Sheffield
SIO 3QP.
Printedin Great Britain
Isolated traumatic anterior dislocation of the radial head-a mechanism of injury in children David Stanley Orthopaedic
Department,
Sheffield
Children’s
Hospital
INTRODUCTION TRAUMATICdislocation of the radial head occurring without a fracture of the ulna is a rare injury. It was first described by Duverney in 1751, and since that time several authors have described both the possible mechanism and management of such an injury (Stelling and Cote, 1956; Vesely, 1967; Lloyd-Roberts and Bucknill, 1977). A girl with such an injury is presented
here and a previously undescribed injury is proposed.
mechanism for the
CASE REPORT A 12-year-old girl had been riding her bicycle when she stopped suddenly and went over the handlebars. She remembered putting her left arm out straight to break her fall. Following the accident she had pain in her elbow preventing movement, and for this reason she came to Casualty. On examination the arm was held flexed at 90” with 10” of flexion and extension from this position. Pain prevented further flexion, extension and rotation. There was very little swelling at the elbow and no neurovascular complication. General physical examination revealed hyperextension of her right elbow, but no other features of abnormal joint laxity. Radiographs showed an anterior dislocation of the radial head without fracture of the ulna (Fig. 1). The dislocation was reduced under general anaesthesia by extension of the elbow followed by flexion with pressure over the radial head (Fig. 2). Reduction was held using a collar and cuff for 3 weeks before a slow resumption of activity was allowed.
DISCUSSION Vesely (1967) suggested that a fall occurring when the entire body weight was caught on the outstretched pronated hand would result in dislocation of the radial
Fig. 2. Lateral radiograph of the same elbow after reduction under general anaesthesia.
head. He thought that this was particularly likely if the force was presented at the annular ligament. Wiley et al. (1974), studying the mechanism of injury using the elbows of corpses, found that anterior dislocation could be produced only with difficulty. To achieve this injury they needed to have the forearm in extreme supination, sever completely the anterior capsule and annular ligament and apply force in an anterior direction to the posterior aspect of the radial head. Even when these conditions were met, anterior dislocation could not be produced without considerable force and without extensive disruption of the annular ligament. In some cases tearing of the upper part of the interosseous membrane occurred before the dislocation could be achieved.
Fig. 1. Lateral radiograph of elbow of 12-year-old girl after injury. The isolated anterior radial head dislocation is shown.
Stanley: Radial head dislocation in children
Fig, 3. Photographs
of the patient’s uninjured
183
arm to show the degree of hyperextension
Although this demonstrates the difficulty of experimental production of an anterior dislocation of the radial head, it does not fit with the clinical presentation of this patient. In part this may be due to differences between living and cadaveric tissue, but age may also be important. Illingworth (1975) showed the ‘pulled elbow’ to be an injury of childhood occurring when the head of the radius was pulled partially through the annular ligament. It is suggested that traumatic, isolated dislocation of the radial head occurring in children may result in part from the forces applied at the elbow, but also from anatomical features of development associated with lax ligaments and allowing hyperextension of the elbow (Fig. 3). In hyperextension of the elbow the radial head may be at risk of displacement either partially through the annular ligament or more anteriorly in a lax annular ligament. If force is now applied down the shaft of the radius as would occur in a fall on the extended outstretched arm, the annular ligament would be disrupted allowing the radial head to be dislocated anteriorly. This is proposed as the mechanism of injury in the case presented, and as a possible mechanism in other children who sustain similar injury.
possible at the elbow joint.
Mr R. H. Baker for allowing me to present his patient. I also thank the Photographic Department at Sheffield Children’s Hospital for preparing the illustrations and Mrs M. E. Leeming for typing the manuscript.
REFERENCES
Duverney J. G. (1751) Traitk des maladies des OS. Paris: De Dure L’Aine. Illingworth Cynthia M. (1975) Pulled elbow: a study of 100 patients. Br. Med. J. 2, 672. Lloyd-Roberts G. C. and Bucknill T. M. (1977) Anterior dislocation of the radial head in children. J. Bone Joint Surg. 59B, 402. Stelling F. H. and Cote R. H. (1956) Traumatic dislocation of head of radius in children. JAMA 160, 732. Vesely D. G. (1967) Isolated traumatic dislocation of the radial head in children. Clin. Orthop. 50, 31. Wiley J. J., Pegington J. and Horwich J. P. (1974) Traumatic dislocation of the radius at the elbow. J. Bone Joint Surg. 56B, 501. Paper accepted 11 September
1985.
Acknowledgements I would like to thank Mr T. W. D. Smith and Mr M. J.
Bell for their help in preparation
of this manuscript and
Reyuem for reyrinfs should he addressed IO: D. Stanley, 7 Stumperlowe Park Road,
Fulwood,
Sheffield
SIO 3QP.