Fracture callus

Antonopoulos, C. A., Engfeldt, B., Gardell, S., Hjertquist, S. Q., Solheim, K. Isolation and identification of the glycosaminoglycans from fractured callus. Biochim. Biophys, Acta 101, 150 (1965)... 

At the microscopic level, bone consists of two structures woven and lamellar (Fig. la). Woven bone (with an average mineral grain size of 10 to 50 nm) is the immature, or primitive, form of bone and is normally found in the metaphyseal region of growing bone as well as in fracture callus (Kaplan et al., 1994 Park and Lakes, 1992). Woven bone is coarse-fibered and... 

Urist, M.R., Wallace, T.H., Adams, T., 1965. The function of fibrocartilaginous fracture callus observations on transplants labelled with tritiated thymidine. J. Bone JL Surg Br. 47,304—318. 

Hertz studied the effect of vitamin A deficiency on the healing of experimental fractures in the rat. He found a delay in the absorption of the fracture hematoma. There was no effect on the inflammatory reactions on the part of the cambial layer of the periostemn, the endosteum, and the marrow, all of which appeared to pass normally through their various phases. The only direct effect of the deficiency appeared to be a poor development of cartilage in the fracture callus. 

Fig. 5.13a,b. Early callus formation following fracture of the distal tibia, a Color Doppler 12-5 MHz US image obtained 12 days after treatment shows a bone defect (arrowheads) related to the fracture site and multiple blood flow signals (arrow) in the periosseous soft tissues superficial to the fracture, b Spectral analysis reveals low-resistance (RI <0.50) arterial flow in the vessels surrounding the fracture. These features indicate initial normal development of fracture callus... 

Caruso G, Lagalla R, Derchi L et al (2000) Monitoring of fracture calluses with color Doppler sonography. J Clin Ultrasound 28 20-27... 

Osteoid Etidronate suppresses bone turnover and may retard mineralization of osteoid laid down during the bone accretion process. In patients with fractures, especially of long bones, it may be advisable to delay or interrupt treatment until callus is evident. 

OI type V is now widely recognized as a distinct OI phenotype with characteristic clinical and radiological features, such as predisposition to formation of hypertrophic callus at sites of fractures or surgical interventions, early calcification of the interosseous membrane of the forearm, and appearance of dense metaphyseal bands in radiographs. Patients have moderate... 

Bone resorption A type of bone loss due to the greater osteoclastic activity than the osteogenic activity. Callus Unorganized meshwork of woven bone which is formed following fracture of bone to achieve early stability of the fracture. 

Open reduction of the fracture will remove the haematoma and may delay the healing response. Radiologically, secondary healing is characterised by abundant periosteal callus. This form of healing is typical in displaced fractures that are treated non-operatively and when non-rigid implants such as intramedullary nails are utilised. 

Fig. 8.11. Oblique fracture of the femur in a child with cerebral palsy stabilized with plate and screws. Medullary canal is too narrow for intramedullary implant. Fracture has united by primary healing. Note the lack of periosteal callus...

Fig. 8.12. Oblique fracture of the humerus 3 weeks post-injury. Extensive callus is visible and outlining the stripped periosteum...

Fig. 9.3. Transverse fracture of femur stabilized with Nancy nails. Note periosteal callus. This is not rigid internal fixation. The nails cross proximal and distal to fracture but are separated at the fracture site giving optimal stability...

Fig. 9.5a,b. Femoral fracture in neonate. Callus visible within 3 weeks. Fracture almost completely remodeled at 3 months... 

Midshaft diaphyseal fractures of the forearm unite more slowly than diaphyseal injuries. Nevertheless, most fractures will be solid by 6 weeks. Whilst the presence of periosteal callus around metaphyseal fractures usually indicates that the bone will be stable, this is not the case with midshaft injuries. Here, the bones may still move within the cast... 

Fig. 11.4a,b. Healing of a metaphyseal fracture without the typical changes of a healing fracture, a Acute metaphyseal fracture. b Follow-up film with no evidence of callus or subperiosteal new hone formation... 

Loss of fracture line definition and appearance of soft callus 10-14 days 14-21 days ... 

With the production of osteoid and its subsequent calcification and ultimate transformation into bone there is an increase in density along the fracture line. With impacted fractures and other fractures where the periosteum remains intact or little disturbed this may be the only evidence of inj ury and it is, therefore, a less valuable sign than subperiosteal new bone and fracture line clarity. Again, movement may inhibit or destroy endosteal callus and a fracture line may remain clearly visible after a bone has united by periosteal new bone. Endosteal soft callus... 

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