A brief overview of fracture healing in small animals and the factors that promotes the healing process

1. Fracture Healing, Complications
& factors promotes the fracture
healing
Presented By:
Surgery Group 2
Presented To:
Dr.Asad Manzoor

2.  Fracture healing
 Goals of fracture healing
Encourage Healing
Restore function
Cosmetically acceptable appearance
 Factors influence the fracture healing
Biologic Events
Mechanical Events

3. Blood supply of healing long bones
Blood supply to bone. A, Normal bone.
B, Immature bone. C, Fractured bone
(extraosseous blood
supply). D, Healing bone.

4. Effect of different fixation devices on circulation to fracture
bone

5. Fracture Healing

6. Phases of fracture healing
 Reactive phase
Inflammatory phase
Granulation tissue formation
 Reparative phase
Cartilage callus formation
Lamellar bone deposition
Trabecular bone formation
 Remodelling phase
Trabecular bone  compact bone

7. Time Distribution of different
phases of fracture healing

8. Inflammatory phase
Hematoma formation soon after the fracture

9. Reparative phase

10. Reparative + Remodeling phase

11. Collagen & muco-polyscharides level
during the fracture healing

12. Indirect bone healing
 Hematoma & granulation tissue formation
 Granulation tissue replaced by fibrous tissue & fibrocartilage
 Local resorption of mineralized tissue
 Vascularization of resorption cavity
 Formation of lamellar bone in this cavity
 Remodeling

13. Indirect bone healing

14. Indirect bone healing
Indirect bone healing A-Bone resorption B-Periosteal callus formation C-
Mineralization of fibrocartilage D-Bone remodeling

15. Direct bone healing
 Fracture having small gaps (150-300µm) between fractured
ends
 Gaps filled with the network of fibrous tissue
 Remodeling of bone union within 7-8 weeks + longitudinal
reconstruction of fracture site
 Radiographicaly slowly increasing density of fracture line
without bridging periosteal & endosteal callus

16. Direct Bone Healing
Direct bone healing
Simultaneous union and reconstruction(A, B)
Gap fills with fibrous bone (C)Haversian
remodeling(D).

17. Direct Bone Healing
Fracture healing in a transverse
radial fracture in mature dog treated with bone plate.

18. Intra-membranous Bone Healing
 Direct differentiation of mesenchymal cells in to osteoblasts
 Bone bridging between comminuted bone fragments after
biologic fixation technique
 Periosteal callus is smaller in comminuted fracture
 Resorption of woven bone & formation of lamellar bone
 Remodeling

19. Intra-membranous Bone Healing
A, Comminuted fractures fixed with
biologic techniques of indirect
reduction, major segment alignment,
and optimal stabilization appear to heal
with a combination
of direct differentiation of
mesenchymal cells to osteoblasts
and endochondral ossification. B, The
fracture site fills with endosteal and
bridging callus. C, Resorption of
woven bone and formation of lamellar
bone at the fracture sites result in
remodeling of bony callus to cortical
bone.

20. Intra-membranous Bone Healing
A, Fracture healing in comminuted nonreducible radial fracture treated
with closed reduction and external fixation. B and C,
Radiographically endosteal bone appears first, followed by bone
bridging between fragments with minimal periosteal callus formation.
D, Bone remodeling occurs after the fracture lines are bridged.

21. Trabecular Bone Healing
 Increase osteoblastic activity on either side of fracture
 New bone deposit on existing trabeculae
 Fracture gap filled with woven bone
 Radiographicaly formation of one or two dense band at
fracture site

22. Trabecular Bone Healing
Metaphyseal fracture healing after a tibial
plateau leveling osteotomy, which is well
stabilized showing trabecular bone healing.

23. COMPLICATIONS IN FRACTURE
HEALING
 Delayed union (healing slower than normal)
 Non-union (arrested fracture repair process)
 Osteomyelitis (inflammatory condition of bone & medullary
canal)
 Mal-union (anatomic bone alignment not achieved)

24. Delayed Union
Delayed healing after 6 weeks of
bone marrow injection
COMPLICATIONS IN FRACTURE
HEALING

25. Non-union of Femur
Radiograph of dog with hypertrophic
nonunion of femur. Notice formation of large
periosteal callus that cannot bridge the fracture.
The fracture was inadequately stabilized with
an IM pin and cerclage wires.
COMPLICATIONS IN FRACTURE
HEALING

26. Non-union VS Mal-union
COMPLICATIONS IN FRACTURE
HEALING

27. Osteomyelitis
Infectious periostitis. A subtle, linear periosteal
reaction (arrows) can be seen along the lateral
aspect of the third toe proximal phalanx. Note
the associated soft tissue increase in volume
and density affecting the third and fourth toes
COMPLICATIONS IN FRACTURE
HEALING

28. Factors promotes the fracture healing
The factors that promotes fracture healing are:
 Growth hormones
 Thyroid hormone
 Calcitonin
 Insulin
 Vitamin K
 Vitamin C
 Vitamin D
 Immobilization

29. Factors promotes the fracture healing
 Anabolic steroids
 Young age
 Nutrition status
 Cerament
 Electric current
 Physical exercise
 Minerals
 High protein diet

30. Suggested Reading
 Griffon DJ: Fracture healing. In Johnson AL, Houlton
JEF, Vannini R, editors: AO principles of fracture
management in the dog and cat, Thieme, NY, 2005, AO
Publishing, pp. 73-97.
 Johnson AL, Egger EL, Eurell JC, et al: Biomechanics
and biology of fracture healing with external skeletal
fixation, Compend Cont Educ Pract Vet 20:487, 1998.
 Wilson JW: Blood supply to developing, mature and
healing bone. In Sumner-Smith G, (editor): Bone in
clinical orthopedics, ed 2, Thieme, New York NY, 2002,
AO Publishing, p. 23.

31. Suggested Reading
 Budsberg SC: Osteomyelitis, In Johnson AL, Houlton
JEF, Vannini R, editors: AO principles of fracture
management in the dog and cat, Thieme NY, 2005, AO
Publishing.
 Johnson AL: Corrective osteotomies, In Johnson AL,
Houlton JEF, and Vannini R, editors: AO principles of
fracture management in the dog and cat, Thieme, NY,
2005, AO Publishing.

32. Any question??????

33. Topic for Performance:
Pinning of long bone