Login | June 16, 2025
Compartment syndrome
PETE GLADDEN
Pete’s World
Published: June 16, 2025
In the past I talked about shin splints, clinically called MTSS (medial tibial stress syndrome), which has to be one of the most prevalent lower limb overuse injuries.
This week I want to revisit the topic of lower limb overuse injuries by examining the shin splint’s distant and insidious cousin, Anterior Compartment Syndrome (ACS).
If you haven’t heard of it then you likely never had it, so consider yourself lucky because this malady can be extremely painful even when well managed - and it’s downright dangerous when left unchecked.
What is ACS?
Well, to answer this let’s first discard the anterior part of ACS and just begin by defining a compartment syndrome.
The Cleveland Clinic defines a compartment syndrome as, “a painful condition that occurs when too much pressure is built up within and between muscles. It can damage muscles and nerves and lead to decreased blood flow. There are two types of compartment syndrome: acute and chronic.”
Now to the compartment, which is a kind of containment vessel where each compartment is surrounded by a fibrous sheath of connective tissue called fascia.
Compartments house muscles, nerves and blood vessels, thereby keeping them wrapped such that they can work together.
Problems arise when this elastic fascia is not able to expand properly - because of overuse or trauma - thus compromising the muscles’ ability to go through proper ranges of motion.
That’s when compartment syndrome symptoms begin to kick in.
Now let’s talk about the compartments of the lower leg, of which there are four/leg.
And the compartment that makes up the shin is the anterior compartment, containing the tibialis anterior, extensor digitorum longus, extensor hallucis longus and the peroneus tertius muscles.
So one of the biggest problems concerning anterior compartment syndrome is that it can trick you initially feeling like plain old shin splints.
Thus, you really want to pay attention to the symptoms you’re experiencing. I’ve had ACS twice, and both times I initially thought I was dealing with shin splints.
The worst case scenario for an ACS is a necrosis of the muscle tissue.
This can occur when swelling starts in the compartment, causing the fascia to push up against the muscles.
When this lower leg fascia becomes inelastic - confining the compartment - fluid can build up within the compartment, pressure in the compartment can increase, and blood supply can be shut off, all of which could possibly lead to permanent muscle tissue damage.
Yup, sometimes that swelling can become so intense that blood flow is blocked and not able to reach muscles, nerves and the blood vessels within the compartment.
That’s when this malady becomes a serious medical emergency and requires a trip to the ER…Pronto.
So how can you tell the difference between shin splints and an anterior compartment syndrome?
An acute anterior compartment syndrome typically involves some form of trauma to the lower limb.
There’s usually a persistent pain that gets progressively worse and the symptoms don’t subside with rest.
What’s more the pain is often disproportionate from the injury that caused it.
Most important to note is a visible swelling, tense, stiff muscles, spotty bruising/discolored skin, tenderness at and below the anterior compartment, pain when stretching the involved muscles, and numbness, tingling, anesthesia (foot feels numb, tingly, and lifeless).
If you have these symptoms then you’ll need to get to the ER asap.
A chronic compartment syndrome is typically caused by locomotive movement involving repetitious activities like running, jumping, etc, and it’s often difficult to distinguish from shin splints in its initial stages.
However once it worsens, chance are good you’ll sense it’s more severe than simple shin splints.
Symptoms include pain on the outside of the shin - specifically along the tibialis anterior muscle - muscle weakness (attempting to pull the foot upwards could be difficult), tenderness and swelling over the tibialis anterior muscle, excessive swelling that causes the skin to be hot, glossy and stretched and pain when the toes and foot are pulled downwards (termed foot drop).
A chronic ACS usually gets better with physiotherapy -. soft tissue stretches and massage.
But you need a doc to make the initial diagnosis and subsequently a physiotherapist to ferret out what factors contributed to the condition and then proceed with the appropriate therapy.
Bad cases of anterior compartment syndrome can sometimes require a surgical intervention to relieve the pressure.
So be vigilant when it comes to severe shin pain…it just might be way worse than shin splints.