This paper presents a method for complexity reduction in medical image encoding that exploits the structure of medical images. The amount of texture detail and structure in medical images depends on the modality used to capture the image and the body part captured by that image. The proposed approach was evaluated using Computed Radiography (CR) modality, commonly known as x-ray imaging, and three body parts. The proposed method essentially reduces the number of CU partitions evaluated as well as the number of intra prediction modes for each evaluated partition. Evaluation using the HEVC reference software (HM) 16.4 and lossless intra coding shows an average reduction of 52.47% in encoding time with a negligible penalty of up to 0.22%, increase in compressed file size.