Lame calf The clinical history was of a 6 weeks lameness that was improving. The calf was kept in a small pasture and consequently was not observed regularly. The distal portion of the limb was noted to be swollen with the swelling centered around the metacarpo-phalangeal joint. No evidence of any soft tissue injury such as a drainage tract was noted. The calf was weight-bearing on the limb Radiographs were made of the foot. The case is presented without additional clinical history LAT Radiographic changes
- The distal metacarpal bone is not of normal bone density, size, or shape and the mcp joint is widened laterally. The physeal growth plate in the distal metacarpal bone appears to be closed. A difference in morphology is noted when comparing the medial portion of the mcp joint and the lateral portion of the mcp joint.
- Well-defined lucent areas are present in the distal metacarpal bone laterally.
- A smooth pattern of periosteal new bone is seen to bridge the lateral aspect of the limb at the physis.
- The joint space between the proximal sesamoid bones and the distal metacarpal bone on the lateral view is not clearly identified.
- Is the bone marked with an arrow on the lateral view a sesamoid bone or a fragment from the physis?
- The distal portion of the limb is angled laterally.
- Soft tissue swelling is minimal
Differential diagnosis
- The differential diagnosis of chronic lameness in this calf would include;
- chronic fracture - supported by the malalignment of the bones and the presence of new bone laterally that could be bony callus and the possibility of a bony fragment caudally
- healing osteomyelitis/infectious arthritis - supported by the suggestion of destructive lesions and the mature periosteal response seen in a healing phase
- congenital/developmental anomaly that lead to development of joint injury - less likely because the lesion is focal and appears centered around the distal metacarpal bone laterally
- nutritional problem - not likely because of the focal nature of the change and the normal appearance of bone density in the other portion of the limb
Radiographic diagnosis
- Bone and joint abnormality secondary to healing bone infection/joint infection without presence of any active periosteal response at this time - OR
- Bone and joint abnormality secondary to healing trauma that included fracture of the metacarpal bone and possible joint luxation
- The injury to the joint and malalignment of the digits may be the more important radiographic finding since they suggest a persistent and progressive lameness and possible problem in either breeding the calf later or having it successfully feed out
Radiographs made 3 weeks earlier provide the possibility of a more complete diagnosis Conclusion
- Fracture of the lateral condyle of the metacarpal bone that is an articular, physeal fracture of the distal metacarpal bone laterally with luxation of the lateral digit
- SO, the injury was traumatic, a Salter-Harris type fracture of the physeal plate, extending through the epiphysis into the joint space, with a luxation of the first phalanx of the lateral digit
- Often as a traumatic, inflammatory, or even nutrutional/ metabolic lesion undergoes healing, especially in a juvenile patient, the healing process makes determination of the etiology impossible without clinical information of the earlier status of the animal
- In this calf, determination of the presence of joint injury with a varus deformity of the foot is most important in a determination of a prognosis
