The above illustration is a cross section of the leg about midway between the knee and ankle. All the “stuff” (muscles, vessels, nerves, etc) have been left out so you can see the distinct compartments. Each compartment houses sets of muscles and, although in reality the muscles work together to provide movement and stability, each set of muscles has their own orientation. The lateral compartment is a sack that holds muscles that generally provide lateral stabilization, the anterior compartment is a sack that hold muscles that generally provide dorsi flexion and the posterior compartment is a sack that holds muscles that provide plantar flexion. These compartments are walled by the septa, the deep fascia of the leg and the interosseous membrane. If all the structures within the compartments fit just right, there is enough pressure to push the blood back up through the vein when the muscles of that compartment contact. Too tight a fit, fluid has trouble getting out; too loose a fit, the muscle have to work harder to push blood up the vessels and may need help. The most common and most dangerous scenario is too tight a fit. Check out the illustration below. It shows the compartments with all their contents. It doesn’t take much imagination to see how conditions in the legs can be tight and uncomfortable, even in normal health legs. No wonder it feels good (and is a good practice!) to put our legs up after a long day!
Anterior Compartment
TA - tibialis anterior
EDL - extensor digitorum longus
EHL - extensor hallucis longus
Lateral Compartment
fibularis longus
fibularis brevis
Deep Posterior Compartment
TP - tibialis posterior
FDL - flexor digitorum longus
FHL - flexor hallucis longus
Superficial Posterior Compartment
soleus
gastrocnemius
Special mention has to be made here of the name of the condition we are addressing. You’ll usually hear people refer to it as just “compartment syndrome” rather than give the full name of chronic exertional compartment syndrome (CECS). This understandable, because CECS is a mouthful, but it is somewhat a misnomer. Compartment syndrome can be either chronic or acute. Acute compartment syndrome (ACS) is brought on by trauma to the leg and is an emergency situation that needs to be addressed immediately. Requisites for determining if the pain in the legs is CECS include anatomical location (as discussed above, in one of the compartment), results from tests that there is increased pressure in the compartments, decreased circulation in the legs, and neuromuscular dysfunction in the structures within the compartments. The “gold standard” for determining pressure in the compartments is to actually insert at probe into the compartment to measure the pressure, although less invasive neurogical tests have recently shown some promise in determining if CECS is the cause of the patient’s pain and dysfunction.
If a diagnosis of CECS is returned, then a decompressive fasciotomy may be an option to relieve the pain and dysfunction. This procedure cuts open the walls of the compartments relieving the pressure on the structures inside. There are several different approaches to the procedure, but the basic procedure is the same. The illustrations below presents one approach where two incisions are made on the lateral aspect of the leg (yes, that illustration is supposed to be a leg!) and the epidermis and subcutaneous adipose is retracted to expose the deep fascia of the leg. Figure 1 clearly illustrates the anterior compartment and the lateral compartments. The darker line that separates them is the anterior intermuscular septum (see the first illustration above for clarity). Note the superficial peroneal nerve where it emerges from the deep fascia of the leg – it is important for both the surgeons performing the procedure and the therapists working with the patient/client to identify it. In figure 2, I have removed the hooks to make it easier to see where incisions have been made in the anterior and lateral compartments.
A similar procedure is execute on the medial side of the leg for the deep posterior compartment, but is complicated by the orientation of the soleus muscle where it attaches to the tibia and must be detached and retracted to expose the deep posterior compartment (see the second illustration for a better visual of why this is necessary). On the medial side, it is the saphenous nerve and vein that must be carefully worked around.
Therapeutic Considerations
Although most decompressive fasciotomies are successful in relieving the pain and dysfunction, allowing the athlete to return to their sport, they will likely need to maintain a regiment of self care in which circulatory massage and cross-fiber friction can play an important role. As with any surgery, massage therapy can help decrease adhesion around scar tissue. With the septa cut and the resistance to muscle contraction reduced, regular circulatory massage can also help maintain the health of the tissues by influencing venous flow. Care must be taken in the areas of scar tissue near nerves, particularly the superficial peroneal nerve.
References:
Williams, E.H, Detmer, D.E., Guyton, G.P., Dellon, A. L. (2009) Non-invasive neurosensory testing used to diagnose and confirm successful surgical management of lower extremity deep distal posterior compartment syndrome. Journal of Brachial Plexus and Peripheral Nerve Injury,4(4)
Rorabeck, C.H., Bourne, R.B., Fowler, P.J., (1983) The surgical treatment of exertional compartment syndrome in athletes. The Journal of Bone and Joint Surgery, 65: 1245-1251
www.mayoclinic.com/health/chronic-exertional-compartment-syndrome/DS00789/DSECTION=treatments-and-drugs
Houglum, Peggy. “Therapeutic Exercise for Musculoskeletal Injuries, 2nd Edition.” Primary and Secondary Healing. Ed. David H. Perrin. Champaign, IL, Human Kinetics, 2005.
Netter, Frank. “The Atlas of Human Anatomy”
Phiadelphia, PA, Saunders-Elsevier, 2003
