Compartment Syndrome

So we all get pumped when we are out climbing, in our forearms. This is natural, but we expect this pump to ease after the route, or at the very most the next day. 
So what happens when it doesn't go the next day, our even gets worse? Then it's quite possible that you're suffering from functional compartment syndrome of the flexor muscles, otherwise known as chronic exertional comparment syndrome (CECS).

Chronic exertional / functional compartment syndrome is much more common in the tibialis anterior muscle compartment in runners and walkers, but has recently been reported in the forearms of those requiring strong grip, such as climbers, motocross riders and rowers.

Physiology and Anatomy 


Within the forearm, all the muscles are surrounded by a thin sheet of fibrous tissue called fascia, which holds all the muscle fibres together in their bundle.

CECS occurs when there is an increase in muscle mass but not in fascia that envelops the muscle tissue, which happens with high intensity training resulting in hypertrophy of the muscles) i.e. muscles grow quicker than the surrounding fascia).
The only space left is veins and arteries and so the vessels become constricted by the muscle mass and creates a back flow of blood and an "instant pump" The muscle still creates lactic acid, but the blood supply cannot remove it, resulting in the pump/burn, that can take days to recover. 

This process can also occur after infectious disease compromises an athletes immune system, but much less common.

Acute compartment syndrome normally occurs post fracture or crush injury, and requires urgent medical attention. This is not the focus of this post.

Symptoms

Pain in forearms during and after stress
Pumped sensation that does not decrease in the usual time frame 
Pump reached way lower than your normal peak levels

Diagnosis

Diagnosis of CECS is using inter-compartmental pressure measurement during the sport specific stress (i.e. climbing) using the devices similar to below.

Schoffl et al (2004) set an algorithm as below for diagnostic of CECS dependant on the pressure found within the muscle compartments.

Differential diagnosis for the symptoms of CECS could be ulnar stress fracture or nerve entrapment

Treatment

• stress reduction i.e. cease to perform the activity, but I know climbers, and they won't stop climbing!
• stretching
• massage
• ice
• anti-inflammatories
• activity modification - analyse your climbing, change your climbing style, crimp less etc.
• surgical procedure - fasciotomy

Fasciotomy

A fasciotomy is one of the surgical options to reduce CECS. It consists of two incisions into each of the different forearm compartments to reduce the pressure within the compartments. They may require a skin graft if the muscle bulk is still too large to close the skin around it.

Outcomes

Painful sensations in the forearm were reduced from 53 to 7 VAS, and more than 95% (23/24) of the motocross patients were satisfied with the postoperative result of a fasciotomy after 5  follow-up. (Winkes et al 2011)

Post fasciotomy of 12 patients reported percentage improvement after surgery was 88%. Median time to return to full activity was 9 weeks. 
(Brown et al 2011)

In 8 post fasciectomy patients, all had resumed their sport in the 6 weeks after the surgery, and 3 returned to their previous level, 5 improved their level. No complications and no recurrences were reported during an average 2-year follow-up. (Croutzet et al 2009)

Physiotherapy post operatively would be to follow the post op guidelines to regain range of movement and strength.

Although surgery is highly effective for most people, it's not without risk. Complications of the surgery can include infection, permanent nerve damage, numbness and scarring. 

Pre and post fasciotomy

Prevention

Unfortunately, there is no real prevention for CECS except to remember that it is really important to build up training and intensity slowly and steadily to ensure all structures within your body adapt to the changes at the same rate, as muscle bulk grows quicker than tendon strength, fascia; and this can lead to problems, imbalances and injuries.

This doesn't mean that all the usual advice doesn't apply, such as warming up and cooling down properly, keeping well fed and hydrated, and "no pain, no gain" is a myth, if your in pain, stop! 

References

Am J Sports Med. 2012 Feb;40(2):452-8. doi: 10.1177/0363546511425647. Epub 2011 Oct 26.
Long-term results of surgical decompression of chronic exertional compartment syndrome of the forearm in motocross racers.
Winkes MB, Luiten EJ, van Zoest WJ, Sala HA, Hoogeveen AR, Scheltinga MR.