Case Reports
Anatomic Variations of the Palmaris Longus Muscle
Am J Orthop. 2010 February;39(2):89-94
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Min Jung Park, MD, MMSc, Surenda Namdari, MD, MMSc, and Jeffrey Yao, MD
Dr. Park is Resident, and Dr. Namdari is Resident, Department of Orthopedic Surgery, University of Pennsylvania, Philadelphia, Pennsylvania.
Dr. Yao is Assistant Professor, Robert A. Chase Hand and Upper Limb Center, Stanford University Hospitals and Clinics, Palo Alto, California.
The palmaris longus muscle exhibits significant anatomical variance compared with other muscles of the upper extremity. The most frequent variation is complete absence of the muscle, but a number of other variations exist. These variations include reversed, duplicated, bifid, or hypertrophied palmaris longus muscles. Many authors have reported the variations in case reports and described them using their own terms. In this case report and review of literature, we aim to consolidate the current knowledge regarding the anatomic variations of the palmaris longus muscle and its clinical relevance.