2021 ISAKOS Biennial Congress Paper
The Risk of Iatrogenic Radial Nerve and/or Profunda Brachii Artery Injury in Humeral Plating using a 4.5 mm Narrow DCP: A Cadaveric Study
Chaiwat Chuaychoosakoon, MD, Hat Yai, Songkhla THAILAND
Supatat Chirattikalwong, MD, Hatyai, Songkla THAILAND
Watit Wuttimanop, MD, Hatyai, Songkhla THAILAND
Tanarat Boonriong, Principal, Hat Yai, Songkla THAILAND
Wachiraphan Parinyakhup, MD, Hadyai, Songkhla THAILAND
Sitthiphong Suwannaphisit, MD, Hatyai, Songkhla THAILAND
Prince of Songkla University hospital, Hatyai, Songkhla, THAILAND
FDA Status Not Applicable
Summary
the 4th screw hole carries the highest risk of iatrogenic radial nerve and/or profunda brachii artery injury.
Abstract
Background
Fixation of humeral shaft fractures with a plate and screws can endanger the radial nerve and/or profunda brachii artery if proper care is not taken. Although prior studies have looked at the risk of radial nerve injury using a 4.5 mm narrow locking compression plate (narrow LCP), no studies to our knowledge have studied this fixation with a 4.5 mm narrow dynamic compression plate (narrow DCP). The objectives is to evaluate the risk of iatrogenic radial nerve and/or profunda brachii artery in anterolateral humeral plating with the 4.5 mm narrow DCP.
Methods
18 humeri of 9 fresh-frozen cadavers were dissected with the anterolateral approach in the supine position with 45 degrees of arm abduction. A hypothetical fracture line was marked at the midpoint of each humerus. A precontoured ten-hole 4.5mm narrow DCP was applied to the anterolateral surface of the humerus using the fracture line to position the center of the plate. Bicortical screws were inserted into all of the screw holes. After the fixation, the distance from each screw hole to the acromion process was measured for calculating the relative ratios with the entire humeral length. The cadaver was then turned over to the prone position with 45 degrees of arm abduction, and a triceps-splitting approach was done to expose the RNPBA. Screw holes that were in contact with or had penetrated the RNPBA were identified as dangerous screw holes.
Results
The most dangerous screw hole was the 4th, for which all 18 screws had contacted or penetrated the nerve, followed by the 5th(12/18), the 3rd(8/18) and the 2nd(2/18). The relative distance ratios compared with the entire humeral length for the distances from the lateral epicondyle to the 2nd, 3rd, 4th and 5th screw holes were 0.64, 0.60, 0.56 and 0.52, respectively.
Conclusion
In humeral shaft plating with the 4.5mm narrow DCP using the anterolateral approach, the 4th screw hole carries the highest risk of iatrogenic radial nerve and/or profunda brachii artery injury. We recommend that only unicortical screw should be used for this hole.
Level of evidence: IV; Cadaveric study