Principles of fractures

1. Principles of fractures Mohammad Ararawi

2. Principles of fracturesDefinition • A bone fracture (sometimes abbreviated # or Fx) is a medical condition in which a bone is cracked or broken; it is a break in the continuity of bone. • Fractures occur when a bone can't withstand the physical force exerted on it. • Bone fracture may be caused by traumatic incident, or also can occur as a result of certain medical conditions that weaken the bones, that may be localized or generalized.

3. Principles of fracturesClassification • In orthopedic medicine, fractures are classified as closed or open (compound) and simple or multi-fragmentary (formerly comminuted). • Closed fractures are those in which the skin is intact. • open (compound) fractures involve wounds that communicate with the fracture and may expose bone to contamination, may be from inside or outside.

4. Principles of fracturesClassification • Simple fractures are fractures that only occur along one line, splitting the bone into two pieces. • multi-fragmentary fractures involve the bone splitting into multiple pieces.

5. Principles of fracturesDescription • Complete Fracture- A fracture in which bone fragments separate completely. • Transverse Fracture- A fracture that is at a right angle to the bone's long axis. • Oblique Fracture- A fracture that is diagonal to a bone's long axis. • Spiral Fracture- A fracture where at least one part of the bone has been twisted. • Compacted Fracture- A fracture caused when bone fragments are driven into each other. • Comminuted Fracture. • Double or segmental Fx, occur at two levels with free segment between them.

8. Principles of fracturesDescription • Incomplete Fracture- A fracture in which the bone fragments are still partially joined. • Greenstick fractures in children, the spriny bone in childhood, buckles on the side opposite to the causal force, where periosteum remains intact. • a compression fracture, an example of a compression fracture is when the front portion of a vertebra in the spine collapses due to osteoporosis. • Reduction is notrequired in vertebral body fracture,But it is necessary when the fractures are part of joint.

9. Greenstick fracture of radius and ulna

10. Principles of fractures • A stable fracture is one which is likely to stay in a good (functional) position while it heals. • An unstable Fx is likely to angulate or rotate before healing and lead to poor function in the long term. • a fracture of the bony components of the joint is called fracture-dislocation. • E.g. shoulder fracture dislocation and elbow fracture dislocation. • Burst fracture, occur in vertebra due to severe violence, acting vertically on a straight spine.

11. Principles of fracturesDisplacement of the fracture fragments • The two main fragments of fracture are commonly displaced • The causes of displacement are: • Primary impact • Gravity • Muscle pull • The following Displacements are recognized: • Shift (translation) of the distal fragment. • Angulation (alignment) of the distal fragment in relation to proximal one or the opposite. • Rotation (twist) one fragment may be rotated on its longitudinal axis.

12. Principles of fracturesclassification • The OTA devised an elaborate classification system to describe the injury accurately and guide treatment. There are five parts to the code: 1-Bone: Description of a fracture starts by naming the bone 2-Location: the part of the bone involved. 3-Type: It is important to note whether the fracture is simple or multifragmentary and whether it is closed or open. 4-Group: The geometry of the fracture is also described by terms such as transverse, oblique, spiral, or segmental. 5-Subgroup: Other features of the fracture are described in terms of displacement, angulation and shortening.

13. Principles of fracturesfractures caused by sudden injury in a normal bone. • Majority of the fractures. • Caused by single excessive force. • According to the force: 1-direct force: A-Direct blow that cause a transverse Fx with damage to skin. B-Crushing force that cause comminuted Fx with extensive damage to soft tissue.

14. Principles of fracturesfractures caused by sudden injury in a normal bone. • 2-Indirect force. The bone breaks at a distance from where the force is applied. A-Rotational force, leading to spiral fracture. B-Bending force, leading to transverse fracture. C-Bending with compression, leading to transverse fracture with butterfly third segment. D-Rotation, bending and compression combined, leading to oblique fracture. E-Pulling force, in which a tendon pull, causes avulsion fracture.

16. Principles of fracturesStress fracture-fatigue fracture • Divided into two categories. • fatigue fractures, is caused by the application of abnormal stress or torque on a bone that has normal elastic resistance, The stress placed on bone causes resorption and microfractures. • insufficiency fractures, On the other hand, occurs when normal muscular activity stresses a bone that is deficient in mineral or elastic resistance Can occur any where but most commonly 2nd metatarsal followed by Fibula and Tibia.

17. Principles of fracturesStress fracture-fatigue fracture • Clinically, Pain with gradual onset, examination will show local tenderness after weeks there will be swelling. • X-ray, MRI and Bone scan.

18. Principles of fracturespathological fracture • Occur through a bone that is weakened by a disease. • Fx occur either spontaneously or from trivial violence. • Local or Generalized disorder of skeleton.

19. Principles of fracturespathological fracture Local causes • Bone infection (osteomyelitis). • Benign tumors (enchondroma, giant cell tumor). • Malignant tumor (osteosarcoma , Ewing sarcoma and metastatic carcinoma).

20. Principles of fractures Generalized causes • Congenital (osteogenesis imperfecta). • Diffuse affection of bone (osteoporosis, rickets, uremic osteodystrophy) • Other causes (Polyostotic fibrous dysplasia, Paget’s disease, Gaucher’s disease).

21. Principles of fracturesGrowth plate injury • Three types of injuries. • Simple separation. • Fractures that cross the growth plate. • Crush injury. Over 10 % of fractures in children involve the growth plate.

22. Principles of fracturesSalter-Harris classification Type I: • The whole growth plate is separated. • No growth disturbances Type II: • The growth plate is separated carrying with it a triangular metaphyseal fragment. • No growth disturbances. • The most common injury.

23. Principles of fracturesSalter-Harris classification Type III: • Part of the growth plate is separated. • May lead to growth disturbances. Type IV: • Separation of part of the growth plate with a metaphyseal fragment. • May lead to growth disturbances.

24. Principles of fracturesSalter-Harris classification Type V: • Crushing of part or all of the growth plate. • Growth disturbances and growth arrest are very common. • The most dangerous injury.

25. Principles of fracturesFracture repair • Fracture repair is a tissue regeneration process rather than a healing process the injured bone is replaced by bone. • The process of repair varies according to: -The type of bone involved. -The amount of movement at the fracture. -The closeness of the fracture surfaces. In tubular bone the pattern of repair shows striking difference than cancellous one. • Two types of tubular bone repair: • Healing by callus • Healing without callus

26. Principles of fracturesHealing by callus 1- Tissue destruction and hematoma formation. • Disruption of blood vessels • A hematoma forms around and within fracture • Few millimeters of the fracture surfaces dies.

27. Principles of fracturesHealing by callus 2- Inflammation and subperiosteal and endosteal cellular proliferation. • Need 8 hours. • Proliferation of fibroblasts, mesechymal cells, and osteoproginetor cells. • New vessels formation.

28. Principles of fracturesHealing by callus 3- Callus formation. • Chondrogenic and osteogenic activity. • Cartilage in the periphery, woven bone near the bone ends. • Marked increase in vascularity. • Osteoclast activity. • At the end the pain disappears and the fragments are rigid w/o movement.

29. Principles of fracturesHealing by callus 4- Consolidation. • The primitive woven bone is transformed into lamellar bone by osteoclastic and osteoblastic activity. • Need several months before the bone is strong enough to carry normal loads.

30. Principles of fracturesHealing by callus 5- Remodeling. Callus is reshaped: the bone along the lines of stresses are strengthened while bone outside these lines removed. • The medullary canal is reformed. • The remodeling depends on age that Fx remodeling in children is so perfect.

31. Principles of fracturesHealing without callus • Callus is formed as a response to movement at the fracture side, to stabilize the fragments rigidly. • Primary bone healing occurs directly between the 2 fragments without callus formation, when the fracture site is absolutely immobile. • Primary bone healing can occur in 2 instances: • Naturally in impacted fractures of the cancellous bone. • In cortical fractures where the 2 fragments are in complete contact and rigidly fixed by metal device(plates, screws or intramedullary nails).

32. Principles of fractures • Cutting cones consist of: - Capillary bud (2) - Osteoclasts (1) - Osteoblasts (3) - Osteoblasts lay down new osteons (4)

33. Principles of fracturesrepair of cancellous bone • Cancelous bone has spongy texture with open meshwork of trabeculae, allowing easier penetration by vessels and bone forming cells. • The broader area of contact between the fragments with good blood supply allow healing in shorter period of time w/o need for callus formation.

34. Principles of fracturesRate of union • Favorable factors. • The age.union occur in 3-5 weeks in children while it needs 3-5 months an adult. • Type of bone.cancellous is better healer. • Good blood supply. • Immobilization. • adequate nutrition (including calcium intake)

35. Principles of fracturesRate of union • Unfavorable factors. • Impairment of blood supply. • Infection • Excessive movement. • Presence of tumor. • Synovial fluid in intraarticular Fx. • Interposition of soft tissue. • Any form of Nicotine.

36. Principles of fracturesApproach • History. • Hx of trauma, deformity, pain, inability to use the limb. Remember: Fx is not always at the site of impact. Some Fx do not need severe violence. Certain fracture will not affect the function of the limb, like greenstick fracture or scaphoid fracture.

37. Principles of fracturesapproach • Examination. General medical condition should be evaluated to exclude shock and brain injury. The vital signs should be observed and followed up. Inspection. expose the area inspect for any swelling, bruising, colour or deformity. special attention is to be paid to the wound in skin-if present. Is it superficial or deep.

38. Principles of fracturesapproach • Palpation, for tenderness, distal pulses, temperature and crepitus on movement. • Vascular injuries are surgical emegency. • Sensation should be examined distally. • Compartment syndrom. • Movement, of the joint distal to the affected area; crepitus and abnormal movement indicates a fracture.

39. Principles of fracturesapproach • Examination of the viscera. Liver and spleen in case of rib fracture. Bladder and urethra in case of pelvic fracture. Neurological examination for head and spinal injury.

40. Principles of fracturesapproach • Investigation Imaging. 1-X-ray criteria in fracture. Two views, AP and lateral. Two joints. Two limbs. Two injuries, like calcaneal fracture you have to suspect vertebral fracture. Two occasions, like stress and scaphoid fractures.

41. Principles of fracturesapproach • Special views, • Calcaneal view, shoulder dislocation needs axial view and acetabular fractures need 45 degree tilt view. 2-CT scan and MR. spinal, pelvic and calcaneal fractures. 3-Radioisotope scan. scaphoid and stress fractures.

42. Principles of fracturesTest of union • Clinical and radiological tests are used to ensure that the fracture is UNITED. • Clinical. • Absence of mobility. • Absence of tenderness. • Absence of pain. Radiological-X-ray criteria. 1-visible callus bridging both fragment. 2-contiuity of bone trabeculae across the fracture.

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