8 May 2013

Injury case study: Knee ligament tear from drop knee

Watch the video below with Dave Graham (which is entertaining anyway) and check out the knee ligament injury he suffered while doing a deep drop knee move.

This injury does happen from time to time in climbers without much warning, so all climbers should read this for prevention’s sake.

One month ago I suffered a very similar injury in an almost identical scenario while training on my climbing wall at home. The striking thing about the injury was that there seemed to be very little I could have done to foresee the injury. I’d just performed the same move several times (falling higher up the problem). The only difference was that my foot didn’t hit the foothold at the perfect angle. But this didn’t feel dangerous or painful until the moment of injury. So was it actually preventable? Well, thats debatable.

Prevention of sports injuries has two main strands. Firstly, by preparing the body for the demands of the sport, usually by strengthening the relevant areas and making sure they are the correct length (stretching muscles to make them longer is not always good). Secondly, by learning about the scenarios that cause the tissue to fail. In some injuries, like the one I’m describing, that’s acute tearing of otherwise symptom-free tissue. In others, it’s degeneration that builds up over years and gradually shows progressive symptoms. 

Taking these strands in turn, is there anything that climbers can do to strengthen the knee to protect it from injuries in drop knees? I’d say it’s pretty difficult. The muscles most forcefully activated during a drop knee depend largely on the exact positioning of the foothold and leg. Moreover, much of the force on the foothold is generated by passively ‘sitting’ on the medial collateral ligament (MCL) that runs down the inner side of the knee. Ligaments are strengthened by general use of the joint. Thus, the best way to strengthen them against the stress they are placed under during drop knees would be to do a lot of drop knees. Albeit less aggressive ones.

The simple maxim when it comes to prevention of tendon and ligament injuries is “tendons don’t like rest or change”. When they are rested, they become weaker. When you increase the demands placed on them, they take a long time to adapt. So perhaps the best protection would be to keep the leg musculature and knee ligaments strong with regular climbing involving this type of move for as much of the year as possible. Supplementation with basic leg exercises with weights or body weight may be a good idea if a specific weakness has been identified that is relevant. But at least some of the time, these exercises are so much of a shot in the dark that they may have little real effect in such specific movement patterns as demanded by climbing. Only a really good physiotherapist or an expert in stability and functional exercises is realistically going to be able to identify these weaknesses through manual testing of an individual. Are you about to go and track down an expert and book a session based on this blog post? Thought not.

So that leaves mitigation of the injury scenario itself. It’s probably fair to say I use drop knees more than most. I’m weak and it allows me to climb things that I otherwise couldn’t touch. I previously irritated my right MCL by trying the crux drop knee on Ring of Steall (8c+) too many times in a row. You can see it in the video in BD's new catalogue here (page 9) Bizarrely, the altered movement I was forced to do because of the pain led me to find the beta tweak I needed and it tipped the balance for success on the route. Most injuries have an upside, somewhere.

I think I’ve got away with only two fairly minor knee injuries in 20 years despite all those drop knees because I learned to take them seriously as a dangerous move. I always take great care to concentrate and ‘feel’ the feedback from the knee to see if I’m properly and safely set before making the hand movement. Also, as I make the hand movement, I remember to keep thinking about the knee so I’m ready to react and let go if the ligament starts to strain or tear. Finally, if it’s a really deep drop knee and and on a redpoint project, I’ll make sure and have a couple of non-committal tries at the move to get a feel for it before fully committing.

Fast movements in such a dangerous position as a deep drop knee are probably more dangerous. Ligaments are ‘viscoelastic’. If they are stretched quickly, they are stiffer. When ligaments are injured at slow speeds, they tend to pull off a chunk of bone (avulse) at their end. When the movement is fast, it’s the body of the ligament itself that tears. So movements where you drop the knee and then move the hand all in one rapid motion are of particular concern.

Another issue pertinent to climbing is the cold. Especially in bouldering, hard ascents are often done in cold conditions with the core body temperature and especially lower limb temperature rather low. Probably dangerously low. In my board I train in just a pair of shorts and my favoured training temperature once warmed up is about -1, with the window wide open to let the highland winter winds in for maximum friction. Ligaments and tendons are stiffer when cold as opposed to being more elastic or compliant when warm. Moreover, joint proprioception (movement and position awareness) is poorer if the joint is cold. Keeping your knees warmer might be a good idea. If you’ve been getting colder for a while, put your shoes back on and run up and down the hill with your duvet jacket for a while. You’ll probably get on better on the boulder too!

Taking all this together, perhaps I injured my MCL because I was cold, I’d just taken a break from rock climbing to do some winter climbing for a month, I was having a good session and may have got a little overconfident. Lastly, it was late in the evening. That is usually my preferred time to train as I’m a night owl. But that particular day I’d done some manual labour moving rocks and mixing cement, followed by a 13 mile run at a good pace, followed by 3 hours of bouldering at my limit. I was probably getting tired and might have been better to stop the session 10 minutes earlier (it was pretty much my last problem before I was going to stop and go to bed). 

On the other hand, the tries immediately preceding the injury went without incident. This goes to show that we always tread a fine balance between training hard enough and injury. The right path is only impossible to see without hindsight.

I got away lightly, I had a partial tear of the MCL and a partial tear of the semimebranosus tendon (hamstrings) which I’ve already largely recovered from in just one month. A bigger concern in drop knees is that they often tear the knee menisci and or the ACL ligament with much more serious complications for the long term recovery and health of the knee. That little nightmare is too long for a blog post, but I’ve just finished writing about them for my injuries book Rock ‘til you drop. There will also be a little more on drop knee injuries in the book, since the MCL isn’t the only ligament hereabouts which can be injured by this move and some of the other ligaments are not so straightforward to rehabilitate.

In summary: Do drop knees, they are a killer climbing technique. But be careful. Concentrate, keep warm and do them year round to keep your knees strong.


Stewart Watson said...

Very good.

Stewart Watson said...

It is so important to stress the body in a safe training environment before the redpoint or competition etc.

Courtney boulders said...
This comment has been removed by the author.
Courtney boulders said...

It's very awesome that you know about and understand what happened. I also injured my knee during a drop-knee (in Feb). Mine was static move and wasn't as much of a drop-knee. I wasn't thinking about weighting my foot because I was trying to reach a hold, so I was twisting my knee more instead of my hip (bad!). It was at the end of a bouldering session at the gym.

My conclusion is that I subluxed my patella, and sprained my MCL. I had some meniscal clicking about a month after, but that's gone away now. And my knee felt sloshy when I was regaining normal gait (tiny bit of ACL). But for the most part, my quad tendon and MCL suffered the most.

The lessons I've learned, which echo what you've posted are to stop when I'm tired and before fatigue sets in (stop when you're ahead), and to pay attention to complex movements like drop-knees. I would argue that mobility exercises (to maintain high quality range of motion)would aid in some prevention of injuries. I agree about keeping warm, general strengthening, and attempting dynamic, yet submaximal moves will also help.

Thanks for the article! Sucks it has to happen at all, but I'm glad I'm not the only one.

Consensus of One said...

It is key for the kinesiology of the knee that when you do drop knees to twist at the hips rather than your knee. That way you keep your knee as a hinge joint and the twisting motion of your leg that gives you strength is from the muscles in your butt(internal rotators of the femur) rather than the ligaments of the knee. If you can't for some reason (hips have to stay parallel to the wall for your other foot placement), don't do a drop knee.

Dave MacLeod said...

The mechanics of where the force comes from and how exactly to twist depends on the move. The bottom line is you've got to be careful because the knee is vulnerable in this position. Split second awareness might save an injury, at least some of the time.