Following the recovery period of bilateral total hip replacement, what concerns or complications should be considered during pregancy and delivery?

-- Will A. (wanderson@oea.umaryland.edu), May 17, 1999

Answers

Will -

The "unconstrained" total hip replacement prostheses in use today rely on the muscles and other soft tissues around the hip as well as on proper placement of the comonents, for stability. Three basic things happen in pregnancy to challenge the implant's stability: 1) weight increases - this increases the moments applied to the components; 2) hormones cicrulating in the bloodstream act to produce lengthening of ligaments and other connective tissues, reducing joint stability in general; 3) the weight distribution shifts further forward, creating larger moments about the hips. Under normal circumstances, these factors remain within the design limits of the prosthetic components. However, sudden or unexpected movements, or vigorous or extreme movements, including standing on one foot for extended periods (reaching up to a top shelf) should be avoided. If the weight gain is especially significant and the prostheses are less than one year old, it might be wise to ask about using some kind of assistive device (canes or crutches) to avoid over-stressing the joints. These kinds of decisions are best made in consultation with the surgeon and/or therapist originally involved. Also, keep in mind that levels of circulating hormones remain high for several months after delivery, and that period is extended if the mother breastfeeds her newborn.

Hope this helps !

- Roy

-- Roy Bechtel (rbechtel@umaryland.edu), May 18, 1999.