Clinical Orthopaedics and Related Research

Donal M. McCarthy, Dean G. Sotereanos, Jeffrey D. Towers, Cynthia A. Britton, and James H. Herndon.


The diagnosis of compartment syndrome is essentially a clinical one. In recent years much interest and research has focused on the development of intracompartmental pressure monitoring devices to help in the diagnosis of this condition. Proper placement of the catheter is essential for accurate monitoring, as an incorrect result is potentially more dangerous than no reading at all. In the forearm, measurement in the flexor digitorum produndus is thought to be a more sensitive way of assessing rising pressure. One of the risks of catheter placement is inadvertent damage to a neurovascular structure, particularly when monitoring pressures in deeper muscle bellies. Standard anatomical texts and outpatient MRI scans of the forearm were studied to define a safe pathway for the introduction of a catheter into the volar forearm. An approach from the midline to the ulna, between the tendons of flexor carpi radialis and palmaris longus, seemed the safest. Ten cadaveric forearms had 100 cc. of gastrograffin injected into the deep forearm through a dorsal approach. The median and ulnar nerves were cannulated with a fine wire from the elbow to the wrist. Two cannulae were passed, utilizing the suggested approach, at two locations between the wrist and the mid forearm. All limbs were then CT scanned and the images reviewed. In all forearms the cannulae passed between the median and ulnar nerves into the belly of the FDP and posed no risk to the neurovascular structures.