Compartment syndrome occurs most commonly after trauma to the lower leg. It causes excruciating pain and may result in muscle death and in some sever cases even death. Detecting these is therefore of uttermost importance and McQueen et al’s recent study on the subject is very welcome. They show that continuous intracompartmental pressure measurement in a clinical setting is feasible and has a high sensitivity and specificity.
They retrospectively identified patients that had lower leg injuries at risk for compartment syndrome at a level I trauma center. All patients that had received a intramuscular measuring device for continuous pressure surveillance were included. The device was positioned in the anterior compartment and a pressure difference of less than 30 mmHg for two hours was considered a strong indicator for compartment syndrome and fasciotomy.
Patients with compartment syndrome were defined in two ways:
- Per-operative findings in combination with inability to close the wound within 48 hours (correct surgical indication).
- Sequelae at follow-up that would indicate a non-treated compartment syndrome (missed patients).
About 15 % underwent fasciotomy and their sensitivity was estimated to 94 % while the specificity was 98 %. From the total number of monitored patients (n=979), 850 were analyzed, out of these 150 had true compartment syndrome where only 9 were missed.
A few study issues
While it is an interesting study one should remember that:
- The definition of compartment syndrome was fairly subjective among those operated. The surgeon may be biased towards describing the situation a compartment, performing unnecessary surgery is less desirable and perhaps even more difficult to explain to the patient. One possible way to remove this bias is to always take standardized per-operative photos and then let an independent observer classify these.
- There was a high percentage of surgery and it is interesting to see how much a fasciotomy impacts function, even if the classification of compartment was accurate, according to the previous bullet, we still risk of increasing the number of surgeries and most of these are probably neither limb- or life-threatening.
- There was no standardized follow-up protocol, a large group lacked any follow-up (> 10 %). It is easy to argue that they may avoid the hospital due to a high degree of dissatisfaction correlated to a missed compartment syndrome, thus a source of selection bias. The probably easiest remedy for this is to try and contact them at study time with a form, or look for visits at other clinics.
Overall I like these kind of hands-on follow-ups of treatment protocols. It is a little pity that the follow-up was so poor, but for hospitals without a high frequency of compartment syndrome this protocol may be very helpful in avoiding missing compartment syndromes.
M. M. McQueen, A. D. Duckworth, S. A. Aitken, and C. M. Court-Brown, “The Estimated Sensitivity and Specificity of Compartment Pressure Monitoring for Acute Compartment Syndrome,” J Bone Joint Surg Am, vol. 95, no. 8, pp. 673–677, Apr. 2013.