A medical assistant is preparing a patient for a flexible sigmoidoscopy examination. In which of the following positions should the assistant place the patient?

For a flexible sigmoidoscopy examination, placing the patient in the left lateral position is ideal. This position, often referred to as the Sims position, allows for optimal access to the rectum and sigmoid colon. It facilitates the insertion of the sigmoidoscope by providing a clear pathway, as gravity helps to displace the bowel gas and fecal matter, making the procedure safer and more effective.

The left lateral position also promotes relaxation of the abdominal muscles, contributing to the ease of introducing instruments. This positioning is a common practice in many diagnostic and therapeutic procedures involving the lower gastrointestinal tract. It helps clinicians gain the best visualization and access needed to perform the examination accurately.