When it comes to knee problems, a PCL injury is a bit like the fabled city of Timbuktu.* Many of us have probably heard of it. But could we pinpoint it on a wall chart? Hmm. Maybe not.
One reason for this is that PCL problems aren’t super-common. Around a fifth of knee ligament tears affect this particular tissue. Yet the PCL is also one of the thickest and toughest ligaments in our bodies. And if you do happen to injure one, well, rarity is neither here nor there. You just want to know what you’ve done and what will happen next.
So… where exactly is my PCL?
PCL stands for Posterior Cruciate Ligament. It’s a companion to the Anterior Cruciate Ligament, or ACL, which you probably have heard of: you can read more about ACLs in this myth-busting blog or in our case studies with former patients Beth and Robb. Both cruciate ligaments run through the knees, connecting the thighbones to the shinbones. They pass each other in a cross (hence ‘cruciate’) but the PCL is further back (hence posterior). It’s also stronger than the ACL.
How would I injure it?
Because the PCL is tougher, it takes considerable force to rupture it. This is why PCL damage usually happens in an acute situation. One common cause is a car accident, where the knee thumps against the dashboard and pushes the shinbone sharply downwards. Another is an activity like football, rugby or even skiing, where you might fall awkwardly onto the upper part of your shinbone.
What does the damage feel like?
Given the above, you’d imagine a PCL injury would be excruciating. But in fact they often aren’t. In fact they can sometimes go undetected. Typical PCL damage leads to swelling around the knee, and sometimes instability or trouble walking and bearing weight. But severe pain is less common, even with a full rupture.
Does a PCL tear mean immediate surgery?
Not at all. In fact surgery is rare. If we suspect you’ve torn your PCL, the protocol usually goes like this: first, we’ll order an MRI scan. If the scan indicates an isolated PCL tear, we’ll get you to rest it, sometimes with the help of a hinged knee brace for extra support. Then we’ll get it moving, because we don’t want your muscles to start stiffening up and weakening.
What do you mean by ‘moving’ it?
Basically it involves some early rehab with a physio. They will help you strengthen surrounding muscles like the quads and hamstrings. Nerve damage around the PCL can also affect your joint positional sense, so the physio will work on your proprioception (your ability to maintain fine balance and motion). This might involve walking along wobbly lines, say, or work with a rope ladder.
What if I’ve suffered a total rupture?
Even if you’ve completely torn your PCL we’ll likely deploy conservative (ie non-surgical) treatment, at least to begin with. With the right rehab, torn ligaments can achieve a certain amount of healing on their own; some of the damaged tissue fibres will ‘stick’ back against surrounding bone and tissue. The ligament can’t rebuild itself completely, but the self-healing process should confer significant stability back to the area, giving you a good range of normal movement.
Do you ever operate on PCLs?
In some cases, yes. This usually happens when additional damage is present in the knee – perhaps a tibia or femur fracture, a chondral injury or a meniscal tear. We’d tend to fix those first before moving on to the PCL, by which time we should have a better sense of how the PCL is faring. It is possible to reconstruct a PCL with surgery (usually keyhole surgery). This works by taking a graft from another tendon, usually your hamstring, and fixing it onto the bone in place of the damaged ligament. The key point, though, is that there’s no need to rush into an operation like this. And in many ways that’s good news. It means we can treat you gently, wait for the natural healing to take place and see how things develop before plunging in.
For more information and advice about ACL and PCL injuries, hop over to the Conditions and Treatments section of our website. If you’d like an opinion on knee pain or a knee-related injury, please get in touch with our friendly team. You can call on 01962 826107 or book an appointment immediately here.
* In case you were wondering it’s in Mali, West Africa.