Discriminatory power of tests applied in back pain during pregnancy

A longitudinal, prospective, observational cohort study.

To assess the relationship between clinical back status and reported pain locations during and after pregnancy.

Back pain during pregnancy is a frequent clinical occurrence, even during the early stages of pregnancy. The cause is unclear. There are few data describing the results of a general physical examination of the back during pregnancy and there are no data on serial examinations. Such data could provide information about what structures cause the pain, which might have implications for the choice of treatment.

A cohort of 200 consecutive women attending an antenatal clinic was observed throughout the pregnancy terms, and repeated measurements of back pain and its possible determinants were taken using questionnaires and physical examinations in a standardized way, including a series of tests of configuration, mobility, and pain provocation.

Pain provocation tests were better at discriminating among women who reported back pain from women who reported no back pain from tests of configuration or mobility. The discriminatory power of the tests was better in the lower part of the spine than in the upper part. The best discrimination was achieved by combining some of the tests.

The results indicate that not one but several pain-releasing structures may be involved. These are probably the various pelvic ligaments, which may form a functional unit. These findings may have therapeutic implications.