How is Forearm Compliance Affected by Various Circumferential Dressings?

Abstract

Background The forearm is the second most common location for extremity compartment syndrome. Compliance is a physical property that describes a material's ability to expand with an increasing internal volume. The effect of circumferential dressings on extremity pressures has been investigated in various animal models and in some nonphysiologic mechanical models, but the importance of this effect has not been fully investigated in the human upper extremity. In addition, the physical property of compliance has not been reported in the analysis of compartment volume-pressure relationships.Questions/purposes We created a physiologic cadaver model for acute compartment syndrome in the human forearm to determine (1) how much volume is required to reach the pressure threshold of 50 mm Hg in forearms, undressed and dressed with various circumferential dressings, (2) differences in forearm compliances that result from dressings, and (3) whether univalving or bivalving of those dressings adequately reduces compartment pressures. Methods A sealed inflatable bladder was placed deep in the volar compartment of seven fresh-frozen cadaveric forearms and overlying fascia and skin were closed. Compartment pressures were measured as saline was infused in the bladder, and compliance was calculated from pressure versus volume curves. This was repeated for each specimen using five external wraps, splints, and casts. At a baseline of 50 mm Hg, each dressing then was univalved (and bivalved, when appropriate for the material) and the decrease in compartment pressure was measured. For each of the seven cadaver forearms, one test was performed without dressings and then for each of five dressing conditions. Results Forearms in fiberglass casts accommodated only a mean of 19 mL (SD, 11 mL; 95% CI, 9-28 mL) before reaching the 50 mm Hg pressure threshold, which was much less than in undressed forearms (mean, 77 mL; SD, 25 mL; 95% CI, 55-98 mL; p \ 0.001). Mean compliances were as follows: ACE TM wrap (1.75 mL/mm Hg; Each author certifies that he or she, or a member of his or her immediate family, has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research 1 editors and board members are on file with the publication and can be viewed on request. Each author certifies that his or her institution approved or waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.

Extremity Pressure in Splints Wrapped With an Elastic Bandage Versus Bias Cut Stockinette: An Experimental Model

“…Many studies have evaluated the below-dressing pressure changes that occur when a cast and/or its underlying padding is split, with uniform demonstration of significant reduction in pressures with increased layers being released. [2][3][4][5][6][7][8][9] These authors have also demonstrated that overwrapping a cast with an elastic bandage after splitting the cast results in a decreased overall pressure reduction and therefore the wrap should be applied gently or not at all.…”

“…Splitting a cast, splint, or the underlying padding can significantly decrease pressure on the extremity. [2][3][4][5][6][7][8][9] The tension with which an elastic bandage is applied over a splint can significantly affect the pressure on the underlying forearm. 2 Many surgeons have advocated for the use of a bias cut stockinette instead of an elastic bandage (commonly referred by the brand name "ACE" wrap) to reduce the risk of pressure-related complications.…”

Impact of Casting and Splinting Manipulations on Below-Dressing Pressures: An Experimental Model

“…Previous reports have identified that fiberglass casts are the least compliant dressing, followed by sugar tong splints and elastic wraps. 9 However, no study to date has studied the compliance of split dressings. Our study reaffirms the notion that swelling can dramatically increase below-dressing pressure, particularly under a cast.…”

Radius- und Ulnaschaftfrakturen

“…Die Verwendung einer intrakompartimentellen Druckmessung hierfür ist umstritten, sollte aber bei Patienten Anwendung finden, die zum Beispiel nach einem Polytrauma nicht adäquat klinisch untersucht werden können (Mcqueen et al 2013). Zirkuläre Verbände sollten bei einem klinischen Verdacht umgehend eröffnet werden (Capo et al 2014). Besteht nach einer Fraktur im Rahmen der operativen Versorgung der Verdacht auf ein Kompartmentsyndrom, sollte bereits primär eine Dermotraktion angelegt und die Wunde erst sekundär verschlossen werden.…”