MEASUREMENT OF PRESSURE PROFILES ACROSS SCOLIOTIC DISCS

Objective: To measure intradiscal pressures in scoliotic spines to further understand the role of mechanical forces in the development of scoliosis. Design: Pressure readings were obtained in consented patients with ethical approval. A needle mounted pressure transducer was introduced into the disc during routine anterior scoliosis surgery. Subjects: Ten human scoliotic discs from three patients. Outcome measures: Intradiscal pressure profiles. Results: Nuclear hydrostatic pressures varied from 0.2 to 0.6 MPa. The mean nuclear pressures for the three spines were 0.27+0.12, 0.35+0.06 and 0.47+0.12 MPa. High stress, non- hydrostatic regions were consistently recorded in the concave annulus. Conclusions: Nuclear pressures in these scoliotic patients were significantly higher than the 0.12 and 0.15 MPa recorded previously in non-scoliotic recumbent individuals 1; 2 suggesting that spinal loading is abnormal in scoliosis.