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.