Radiology Packet 26

Fracture Complications

2 yr old FS Mix breed dog

• HX = referred with a history of an acute injury that occurred 3 months ago, at that time the rDVM diagnosed a fracture of the left radius and ulna and placed the limb in a cast, the dog remains non weight bearing

2 yr old FS Mix breed dog• RF

– Large fracture gaps are still evident in the distal diaphysis of both the radius and ulna.– The end of the bones adjacent to the fracture gap appeared widened as a result of callus

formation, however the callus does not bridge the fracture gap.– In addition, the ends of the bones appear mildly sclerotic and there is evidence of mild

sclerosis of bone in the medullary cavity.– The bones of the carpus and phalanges appear more lucent than normal and have a

prominent trabecular pattern which is evidence of loss of bone mineral content.• RD

– Non-union(hypertrophic) of the radius and ulna– Disuse osteopenia

• Next– Surgical correction

7 mo old M Gordon Setter“Hamish”

• HX = fractured R tibia 5 weeks ago and treated via application of a cast

7 mo old M Gordon Setter“Hamish”

• RF– There is a large amount of osseous callus at the level of the

fracture but does not appear to bridge any of the cortices of the bone.

– There is an increased opacity of the medullary cavity of the tibia on either side of the fracture which is evidence of bone formation and “sealing” of the marrow cavity.

• RD– Non-union(hypertrophic) of the right tibia

9 yr old M Bull Terrier“Mojo”

• HX = fractured right tibia repaired in January using an IM pin, a cerclage wire and a hemicerclage wire

9 yr old M Bull Terrier“Mojo”

• RF– A single pin remains centrally in the mid-diaphysis of the tibia.– There is fluffy and irregular periosteal response on all cortices of the tibia.– In the CC view there is a distinct bone fragment in the central diaphysis.– The soft tissues are mildly thickened.– The patient also has capsular distension and osteoarthritis of the right stifle.

• RD– Healing tibial fracture– Resolving osteomyelitis (need prior radiographs to be certain)

7 mo old M Mix breed dog“Duke”

• HX = fractured R radius and ulna two weeks ago which was treated with a cast

7 mo old M Mix breed dog“Duke”

• RF– The fractures are healing by second intention and a callus has formed at the site

of each fracture and is undergoing mineralization.– Bridging of the cortex by the callus is visible only on the lateral margin of the

radial fracture.– The callus is incomplete on the remaining surfaces of the radius.– The callus has bridged the lateral and medial aspects of the ulnar fracture but is

incomplete on the caudal aspect.– The radial fracture has healed in minor mal-alignment and there is cranial

angulation of the distal radius.• RD

– Healing radial and ulnar fractures– Mal-union of the radial fracture

7 yr old M Mix breed dog“Pee Wee”

• HX = the dog fractured its radius 3 weeks ago and it was repaired with an intramedullary pin but he is not using the leg well currently

7 yr old M Mix breed dog“Pee Wee”

• RF– There are short oblique fractures of the radius and ulna in the proximal diaphysis.– An IM pin has been placed retrograde across the radial fracture.– The fracture fragments are mal-aligned and there is almost no evidence of

fracture healing.– The margins of the radius at the level of the fracture are narrow and this is typical

of an atrophic non-union.• RD

– Implant failure– Delayed healing– Developing non-union??

• Next– Surgical removal of the implant– Surgical correction of the fracture

2.5 yr old MC GSD“Rex”

• HX = The patient was hit by a car and suffered radial and ulnar fractures approximately 1 month ago at which time they were plated. It has been licking excessively at the cranial service of the antebrachium.

2.5 yr old MC GSD“Rex”

• RF– The radial and ulnar fractures appear to be healing(ideally the initial post-op films

would be needed to compare).– The implants are stable and there is no evidence of lucency around any of the

implants.– There is an irregular periosteal response on the lateral and medial surfaces of

the radius and the caudal surface of the ulna.– The soft tissues are circumferentially thickened from the mid-radius distally.

• RD– Healing radial and ulnar fractures– Stable implants– Suspected soft tissue infection +/- early osteomyelitis

• Next– Initialization of antibiotic therapy