Pressure reducing wedge The Invacare Softform Odstock Wedge was developed in partnership with clinicians to assist in the reduction of interface pressures on the sacrum and heels without significantly increasing pressure on the thighs or calves. It is designed to improve and maintain patient posture in the recumbent position, and to reduce the tendency for the user to slip down the bed, thereby reducing shearing forces on the sacrum. The Odstock Wedge is ideal for improving posture in those with back discomfort.