James had injured his knee on a rambling trip in France. After consulting his family doctor he was advised to work out on an exercise bike. This just made the knee worse so he consulted a second doctor who sent him for physiotherapy. The physiotherapist referred him to a gym, where the fitness manager put him through a rigorous programme of exercise with a rowing machine, treadmill and cross-trainer. Imagine his misery when instead of the knee getting better it swelled up, became much more painful and he found himself wondering if he should buy a walking cane and move to a downstairs apartment. What was going on?
Well, knee rehabilitation after injury or surgery is not just a case of going to the gym and pushing through the pain. In this case, none of the medical people had made a proper diagnosis, but even without a diagnosis the knee itself was making it clear that the exercise regime was inappropriate.
You see, the body follows a natural progression of healing. Each step of the rehabilitation programme needs to be in sympathy with this healing process. If not, one can do a lot of harm.
After any insult to the knee the inflamed joint lining produces increased fluid and a cascade of chemicals that appear one after the other in a specific sequence. The early part of this cascade encourages blood vessels to dilate and become leaky. Blood plasma containing immune cells leak out of the blood to enter the damaged area and try to clean it up and prevent infection. This whole process contributes to the knee feeling swollen, hot, red and painful. This is called inflammation. Different chemicals emerge later in the cascade to promote closing up of the injury and enhance healing through formation of scar tissue to replace damaged or missing tissues caused by the original injury.
If the knee keeps getting stressed, then the choreography breaks down and the inflammation cascade occurs at the same time as the scarring cascade. This can sometimes prove disastrous, with a hot swollen painful knee stiffening up with sticky adhesions within the knee cavity and the lubricating pouches around the knee, tying previously mobile tissues together and reducing movement within the joint. Without the right attention these adhesions can turn into scar tissue.
To give your knee the best chance of benefiting from a rehabilitation programme you must clearly identify what phase of rehabilitation your knee is in. You need to know what the phases are and the dos and don'ts of each phase. You need to be able to recognise when you have pushed things too far for that phase and what to do about it if you do.
In the early stages of rehabilitation after injury or surgery be sensitive to the fact that the knee lining is likely to be inflamed. The swelling and pain that are normal in this phase may cause the muscles, especially the quads muscles, to become inhibited and unable to contract properly. Gentle sustained stretches ensure that the tendons of the inhibited muscles do not shorten and limit movement in the future. Gentle progressive movement is necessary and really important to lubricate the joint properly and to break down any adhesions. Simple 'balance' exercises improve balance and position sense in the knee, both of which can easily be lost at this stage leading to re-injury. Rest, ice, compression dressings and elevation are needed after each session to try and minimise swelling. While the inflammation settles you may have to limit some activities and then build these activities up again gradually during the later healing stage.
Only when you have close to full range of movement should you start to concentrate on rebuilding strength. Keep in mind when starting strength training that muscles act in complementary sets. For example, you need to exercise the muscles that bend the knee as well as those that straighten it. Too much emphasis on one set of mucles may lead the complementary set to weaken which destabilises the knee. The quality and timing of the muscle contraction is also important in re-building muscle strength efficiently.
Under ideal conditions, rehabilitation would progress smoothly from strength training to endurance training and then back to full activities. But moving to endurance training too early can again trigger an inflammatory response and set rehabilitation right back with more swelling, pain, muscle inhibition and loss of the range of motion you may already have regained. This is what happened in James's case. He had already lost time off work, and had now wasted all his efforts in going to the gym.
In this scenario, pushing through the pain is not going to fix the knee. It will only make things worse. With knees, repeating cycles of healing and then renewed inflammation signify that you are pushing too hard and are not being careful enough in your rehabilitation programme. Back off right down again to the first stage of rehabilitation. Return your focus to dealing with the inflammation not the strengthening or endurance. While that might seem like a step backwards, it is really a step forwards towards your ultimate goal of getting better.
Start again with rest, ice, elevation, compression, and possibly anti-inflammatory medication. Stretches and gentle flexibility exercises should be continued, but only when the inflammation settles should you return to strength and endurance training. If you cannot manage this on your own, a good physiotherapist with experience in knee rehabilitation should be able to resolve the problem before things deteriorate too far.