Clinical historyA 7 month old male Afghan hound was hit by a car and presented with a severe injury to the left forelimb. There appeared to be a deep cut near the radiocarpal joint. No evidence of crepitus was detected on palpation. Soft tissue swelling was prominent limiting physical examination. A radiographic study was made of the forelimb.Radiographic views of the left forelimb made on day 1 following injury Enlargement of the antebrachiocarpal region on day 1 Radiographic diagnosis
- Generalized soft tissue swelling
- Fracture of the styloid process with minimal fragment separation - fracture does not appear to involve the distal ulnar physeal plate
- Radiocarpal joint appears to be normal
- Proximal angulation of the accessory carpal bone suggests injury to the distal ligaments from the accessory carpal bone that attach to MC5 and MC 4.
- Distal radial physeal plate was evaluated as normal
Radiographic studies made 22 days later Radiographic changes
- Marked dorsal angulation of the distal radial epiphysis with epiphyseal modeling is the result of a Salter-Harris Type 1 physeal fracture
- Callus around the distal radial metaphysis is most prominent on the dorsal cortex where it is beginning to bridge the fracture site created by the slipped epiphysis
- Further separation of the ulnar fragments without callus formation suggests fragment motion
- Distal ulnar physeal plate is not easily seen suggesting that early closure is taking place
- Persistent proximal angulation of the accessory carpal bone continues to suggest injury to the distal ligaments
- Early subluxation/malalignment of the radiocarpal joint
- Regression of the soft tissue swelling
- Elbow joint remains within normal limits
Normal studies at 6 and 9 months of age of other dogs - note the normal relationship of the distal radial metaphysis and epiphysis on the medial side (arrows) Comments
- The Salter-Harris Type 1 fracture was not detected on the original studies Comparison studies of the opposite normal limb were not made which could have permitted the detection of the fracture
- Evaluation of the normal studies from other dogs shows that the distal epiphysis had slipped laterally indicative of the physeal injury
- Stress studies could have assisted in making the diagnosis on the first study
- Unfortunately the owner was not advised of the possibility of subsequent growth plate injury at the time of the original injury
