The biological and biomechanical effects of irradiation on anterior spinal bone grafts in a canine model.

We evaluated the effects of irradiation on the healing of anterior vertebral strut grafts with use of a canine model. Through a left thoracotomy, a partial corpectomy of the seventh thoracic vertebra and autogenous iliac strut-grafting from the sixth to the eighth thoracic levels were performed in twenty-two adult beagles. Four groups were established: Group I (control) received no irradiation, Group II received preoperative irradiation, Group III received postoperative irradiation that began on the third postoperative day, and Group IV received postoperative irradiation that began on the twenty-first postoperative day. The irradiation protocol was five treatments of 500 centigray three times a week for a total of 2500 centigray. Fluorochromes were administered at regular intervals postoperatively. The beagles were killed three months postoperatively, and non-destructive biomechanical testing was done to evaluate the stiffness of the construct. The quality of healing at the junctions of the graft with the sixth and eighth thoracic vertebrae, the degree of revascularization of the graft, and the amount of new-bone formation were evaluated histologically. Statistical evaluation of the biomechanical data revealed no significant difference in the stiffness of the construct between Groups I, II, and IV. The specimens from Group III were significantly less stiff than those from Group I (the control group) in torsion (p = 0.03) and left lateral bending (p = 0.04) and than those from Group II in flexion (p = 0.02) and left lateral bending (p = 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

[1]  Y. Shibamoto,et al.  Changes in bone after high-dose irradiation. Biomechanics and histomorphology. , 1991, The Journal of bone and joint surgery. British volume.

[2]  M. Panjabi,et al.  The effect of radiation on the fracture repair process. A biomechanical evaluation of a closed fracture in a rat model , 1989, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[3]  S. Emery,et al.  Treatment of hematogenous pyogenic vertebral osteomyelitis with anterior debridement and primary bone grafting. , 1989, Spine.

[4]  D. Davy,et al.  The Superiority of Vascularized Compared to Nonvascularized Rib Grafts in Spine Surgery Shown by Biological and Physical Methods , 1988, Spine.

[5]  T. Albrektsson,et al.  Dynamics of irradiation injury to bone tissue , 1985 .

[6]  R. Marx Osteoradionecrosis: a new concept of its pathophysiology. , 1983, Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons.

[7]  R. Datta,et al.  Quantitative determination of tolerance doses for preoperative and postoperative radiotherapy of bones. , 1983, Medical physics.

[8]  Z. Fuks,et al.  Anterior decompression of the spine for metastatic epidural cord compression: A promising avenue of therapy? , 1982, Annals of neurology.

[9]  C. Orton,et al.  A simplification in the use of the NSD concept in practical radiotherapy. , 1973, The British journal of radiology.

[10]  H. Suit,et al.  Effect of fractionation of radiation dose on callus formation at site of fracture. , 1971, Radiology.

[11]  A. Fingerhut,et al.  Radiation-induced delayed union of fractures. , 1969, Radiology.

[12]  P. Rubin,et al.  Nonunion of pathologic fracture after radiation therapy. , 1967, Radiology.

[13]  T. Albrektsson,et al.  Dynamics of irradiation injury to bone tissue. A vital microscopic investigation. , 1985, Acta radiologica. Oncology.

[14]  R. Pelker,et al.  Radiation‐induced alterations of fracture healing biomechanics , 1984, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[15]  T. Albrektsson,et al.  Irradiation injury of bone tissue. A vital microscopic method. , 1980, Acta radiologica. Oncology.

[16]  R. D. Marciani,et al.  Cancellous bone marrow grafts in irradiated dog and monkey mandibles. , 1979, Oral surgery, oral medicine, and oral pathology.

[17]  H. Woodard The influence of x-rays on the healing of fractures. , 1970, Health physics.