OTA 2005 Posters

Scientific Poster #16 Polytrauma/Injury Prevention

Does the Application of Bridging External Fixation Across the Knee Raise Compartment Pressures of the Leg?

Jamal Bazzi, MD; Nirmal Tejwani, MD; Toni McLaurin, MD;

Kenneth A. Egol, MD (n-all authors);

NYU Hospital for Joint Diseases, New York, New York, USA

Purpose: External fixation is frequently used for provisional and/or definitive stabilization of severe closed fractures and dislocations about the lower extremity. There is some concern, however, that application of external fixators and reducing fractures with distraction may precipitate the development of compartment syndrome. The objectives of this study were to examine the effects of the application of spanning external fixation across the knee on compartmental pressures of the leg.

Methods: Between October 2003 and November 2004, 15 consecutive patients who underwent immediate knee-spanning external fixation were admitted to one of two level 1 trauma centers in our department. All four compartments of the injured leg were measured using the compartment pressure monitor (Stryker Instruments, Warsaw, IN) during the temporizing procedure. In addition, at the time each pressure reading was taken, the patient's diastolic pressure was recorded off the anesthesia monitor. Each of the compartments was measured four times: (1) after the patient had been draped but before any fixation or reduction of the fracture, (2) immediately after the insertion of the fixator pins, (3) immediately after reduction of the fracture, and (4) 5 minutes after the reduction. An absolute threshold of >50 mmHg or <30 mmHg differential from diastolic pressure was set as an indication for four-compartment fasciotomy.

Results: 15 patients with a mean age of 52 years (range, 21 to 69)were enrolled in the study. Injuries were tibial plateau fractures (OTA types 41C) in 13 patients and knee dislocation in 2 patients. One plateau fracture was open; all other injuries were closed.

Table 1. Mean Pressure in mmHg (with range) in Different Leg

Compartments at Various Stages of the Procedure

	Anterior	Lateral	Superficial Posterior	Deep Posterior
Before pins	23.3 (6-43)	17.4 (4-44)	15.7 (3-34)	22.1 (2-40)
After pins	20.5 (7-44)	14.6 (1-34)	12.7 (3-41)	18.9 (2-36)
After reduction	17.7 (3-34)	18.5 (0-37)	13.1 (2-29)	19.6 (4-40)
End of procedure	20.8 (3-42)	21.1 (0-36)	16.1 (3-35)	18.3 (5-36)

There were no significant trends toward increased compartment pressures as a result of this procedure. Fasciotomy was not required in any case and compartment syndrome did not develop subsequently in any patient.

Conclusion: Application of knee-spanning external fixation as a temporary measure for tibial plateau fractures does not precipitate any significant increase in leg compartments' pressure and does not appear to lead to compartment syndrome.