Anterior compartment syndrome or chronic exertional compartment syndrome (CECS) is a condition that I never usually like seeing as it is difficult to manage and most would be better off having surgery. This is a problem that occurs to the expanding muscle in the tight fascial compartment of the leg. A recent study on forefoot striking and this condition has raised some interesting questions about how much evidence is needed to change clinical practice.
Forefoot Running Improves Pain and Disability Associated With Chronic Exertional Compartment Syndrome
Angela R. Diebal, Robert Gregory, Curtis Alitz, and J. Parry Gerber
Am J Sports Med published 16 March 2012
Background: Anterior compartment pressures of the leg as well as kinematic and kinetic measures are significantly influenced by running technique. It is unknown whether adopting a forefoot strike technique will decrease the pain and disability associated with chronic exertional compartment syndrome (CECS) in hindfoot strike runners.
Hypothesis: For people who have CECS, adopting a forefoot strike running technique will lead to decreased pain and disability associated with this condition.
Study Design: Case series; Level of evidence, 4.
Methods: Ten patients with CECS indicated for surgical release were prospectively enrolled. Resting and postrunning compartment pressures, kinematic and kinetic measurements, and self-report questionnaires were taken for all patients at baseline and after 6 weeks of a forefoot strike running intervention. Run distance and reported pain levels were recorded. A 15-point global rating of change (GROC) scale was used to measure perceived change after the intervention.
Results: After 6 weeks of forefoot run training, mean postrun anterior compartment pressures significantly decreased from 78.4 ± 32.0 mm Hg to 38.4 ± 11.5 mm Hg. Vertical ground-reaction force and impulse values were significantly reduced. Running distance significantly increased from 1.4 ± 0.6 km before intervention to 4.8 ± 0.5 km 6 weeks after intervention, while reported pain while running significantly decreased. The Single Assessment Numeric Evaluation (SANE) significantly increased from 49.9 ± 21.4 to 90.4 ± 10.3, and the Lower Leg Outcome Survey (LLOS) significantly increased from 67.3 ± 13.7 to 91.5 ± 8.5. The GROC scores at 6 weeks after intervention were between 5 and 7 for all patients. One year after the intervention, the SANE and LLOS scores were greater than reported during the 6-week follow-up. Two-mile run times were also significantly faster than preintervention values. No patient required surgery.
Conclusion: In 10 consecutive patients with CECS, a 6-week forefoot strike running intervention led to decreased postrunning lower leg intracompartmental pressures. Pain and disability typically associated with CECS were greatly reduced for up to 1 year after intervention. Surgical intervention was avoided for all patients.
This was quite a dramatic study. All 10 subjects were spared surgery after the transition to forefoot striking. Is this enough evidence to transition all those with CECS to forefoot striking to manage it?
At one end of the spectrum, you have people who change clinical practice on a whim based on a n=1 experience (ie it worked for me, so it must work for everyone else) and at the other end of the spectrum there are those that argue we should wait until there is enough randomized controlled trials to inform the clinical decision making process (for eg, see Bø & Herbert). If you had a medical condition and was on a powerful drug for that, which end of that spectrum would you like your doctor to sit before changing the drug? Where does the above study sit on that spectrum? Unfortunately it sits way down the end of not much evidence at all (which the authors admit: ‘Level of evidence, 4′ – there are only 5 levels).
The big problem with this study is that despite the very significant reduction in pressures in the anterior compartment and all 10 subjects avoiding surgery, there was no control group. Without a control group we know from experience that effects are often overestimated and all the effects could have been due to placebo. (And obviously all those who thought 36 was too small a sample size in the bone stress injury and minimalism study should immediately dismiss the above study with 10 only subjects!).
What should a clinician do, especially in the context of evidence based practice, when confronted with a patient with CECS in the anterior compartment? Obviously those who promote the minimalism agenda will of course say yes, transition them to forefoot striking. Obviously those who who promote evidence based practice agenda will, of course say no, do not transition them to forefoot striking as we do not have enough evidence. Clinicians need to make reasoned clinical decisions and not be taken in by propaganda and rhetoric of agendas¹. This is why we need to rely on the strength of the scientific data to avoid that trap.
In the absence of evidence, what should we do? What I like to apply are 3 criteria: is the intervention biologically plausible, is it theoretically coherent and is it consistent with the available evidence? In this context we know that in forefoot striking that the anterior tibial muscle is not used to lower the forefoot to the ground like it does in heel striking, so it is biologically plausible and theoretically coherent that forefoot striking will not work the anterior tibial as much as heel striking. This is also consistent with the evidence of Giandolini et al that showed a significant decrease in tibialis anterior EMG activity in forefoot vs heel striking, so yes it looks as though the anterior tibial muscle is used less in forefoot striking and this could potentially explain the mechanism by which forefoot striking could have helped CECS (ironically, this also makes a mockery of all those claims that barefoot running and minimalism strengthen the muscles of the foot and leg – the anterior tibial muscle will theoretically become relatively weaker with this as its less active!).
So what do we have: some weak evidence from a small uncontrolled study but with dramatic results (all subjects spared surgery) and a theoretically coherent and biologically plausible mechanism that is consistent with the evidence (and there is not a hint of contradictory evidence or any evidence the putative mechanism is inconsistent with). Is that enough to change clinical practice? I think it probably is².
As always, I go where the evidence takes me until convinced otherwise.
¹See the Tweet mentioned down in the discussion on this topic here, that claimed there were 12 studies that support this. No there is not!
²And for other injuries, it would be a bad option. See: Which injuries are probably more common in which foot strike pattern? (Also, see the comments on the article on PTTD in runners!)
Diebal, A., Gregory, R., Alitz, C., & Gerber, J. (2012). Forefoot Running Improves Pain and Disability Associated With Chronic Exertional Compartment Syndrome The American Journal of Sports Medicine, 40 (5), 1060-1067 DOI: 10.1177/0363546512439182