A lot of guidelines exist for management of acute injury. Most people will have heard of RICE, PRICE or, more recently POLICE. But what do you do when the acute phase ends? Continue with the ice? Stick your running shoes on and hit the road? This blog is to help you manage the next part, the sub-acute stage.
This advice is most useful for actual injury management, rather than a tight hamstring or a flare up of an old problem. As ever with this blog, it is not designed to replace medical advice – if in doubt get it checked out!
When does the sub-acute stage start?
There is no definitive timescale for healing as different things heal at different speeds but the sub-acute stage starts when the initial stage of swelling and pain has started to settle. There is usually a lot of bleeding in the first 6-8 hours post injury and a lot of inflammation for 2-3 days so the sub-acute stage usually starts between 3 and 7 days post injury and lasts until around 3-4 weeks.
What healing is taking place at this stage?
After the initial bleeding and inflammation your body starts the repair work. It does this by laying down new tissue usually in the form of collagen. This collagen starts off disorganised and “immature” and is not very good at managing load. If you place too much stress on this healing tissue it will breakdown and cause more swelling and pain. At around 3 weeks post injury the collagen has usually matured to a level where it is more efficient at dealing with some load but it takes 6-8 weeks to fully mature. Even beyond this stage tissue is being “remodelled” and strengthened further. Some structures will continue to heal in this way over a year after the initial injury. That said, we often consider things to be healed when they have reached a level where they can manage normal load and are without pain. Bone and muscle injuries take around 6-8 weeks to reach this level, ligament and tendon takes around 12 weeks. Areas with poor blood supply can be significantly longer.
What affect will the injury have on surrounding tissues?
Some injuries have immediately obvious effects. Injure a muscle and you would expect that muscle to be weak, but what if you injure a ligament or a bone? The resulting swelling and pain from an injury usually affect muscle strength, tissue flexibility, joint range of movement, balance and control of movement. An ankle ligament sprain, for example, usually causes a lot of swelling. The ankle joint stiffens as a result, the calf muscle may tighten, the muscles around the ankle become weak and it becomes very difficult to balance.
It is these issues that need to be addressed post injury to allow a problem free return to running. It often boils down to The Big Three movement control, range of movement and strength.
In the sub-acute stage you need to be guided by your pain, don’t push through pain and if you have specific instructions from your consultant or Physio stick to those.
Rehab of movement control
Part of movement control is something called “proprioception”, it’s how our bodies know the position of joints, muscles etc in space. It tends to be reduced after injury as described above. Movement control and proprioception work can be started as soon as comfortable after an injury, as it can be done very gently. Start with non-weightbearing exercises, this could be sitting with a ball under your foot, rolling it side to side, back and forwards, in circles etc or keeping a wobble board level (again in sitting). Some people do “alphabets” with their feet – drawing each letter of the alphabet in the air. A pool is a great place for balance exercise, bare in mind that if you are chest deep in water you reduce your weightbearing by about 80%. If it’s comfortable you could try single leg balance in the water, walking on your tip toes or heels and sideways walking. To gradually increase the amount of weight you take through an injured limb go progressively shallower in the pool. This is a great way to prepare for weightbearing work.
When comfortable you can progress to exercises in standing (out of the pool). You could start with 2 leg activities like gentle squats or wobble board balance and progress to single leg work balance work (detailed here). Use as much or as little support as you can manage, your aim is restore balance without causing pain or placing too much stress on healing tissue.
Restore range of movement
It’s important not to be overly aggressive in this area, find which movements are stiff and gently work into them. Common problem areas are ankle dorsiflexion (the upward movement), ankle inversion and eversion (turning the foot in and out) and knee flexion. Again, start in non weightbearing e.g. simply moving the foot up and down and in and out or bending and straightening the knee. You can try a static stretch as long as it’s comfortable, gradually build up towards a 30 second hold. When you feel ready progress to assisted stretching e.g. Using a towel or resistance band to add to the stretch, then add weight bearing stretches when able. Restoring range of movement isn’t just about stretching muscles, it’s about moving the joint. For example, simple squats and lunges can be very effective to loosen an ankle that’s stiff into dorsiflexion (I.e. won’t bend up) even though there may be little stretch on the calf muscles.
Common muscles to be weak post injury are calf, quads, hamstring and glutes.
Try to gently work the muscles around the injured area as soon as it’s comfortable to do so. Start with isometric exercise. This means contracting the muscle without change in joint angle or muscle length. It’s a fairly static exercise so there is little stress on healing tissue, with the exception of the muscle you are working. One way to do this is to push against an immovable object, like a wall or the floor. You can even resist it with your good leg/arm. An isometric contraction can also be at the joint’s end of range where the joint itself prevents movement, for example static quads (sit on the bed with the leg straight and tighten the quads muscle). Muscle contraction also has the added benefit of improving swelling as it has a pumping action that helps move fluid from within the tissues. For other isometric exercises see the table below.
When comfortable you can progress from isometric strength work to working through range. Often it’s best to allow 7-10 days post injury to make this transition, after all, we need to allow the area to heal and there is little to gain in pushing things too quickly. Just the weight of the limb can offer enough resistance, e.g. with a straight leg raise exercise for quads. Body weight can also be used e.g. with squats or calf raises. Additional weights or resistance bands can be used if needed. It should remain pain free. Just work in whatever range is comfortable. Strength can also be gained by using equipment, like a static bike. Start with a low resistance and gradually increase. Keep movement comfortable and controlled.
How many, how often?
While the healing continues the priority is protecting that process, so if in doubt do less rather than more. Think of it as gently keeping things ticking over to prevent deconditioning (muscle weakness, joint stiffness etc.) rather than working hard to build strength. These exercises are best done little and often rather than all at once. I usually suggest that patients pick 3 or 4 exercises and do those about 3 times per day (morning, noon and evening) just doing as much as comfortable of each exercise. This might be as little as 4 or 5 reps. Which exercise you choose depends on what problems you are having following your injury. If you have no range of movement problems but feel very weak you would focus on strength work. If the muscles feel strong but the joints are stiff you would focus on improving range of movement. If strength and range are good but you struggle to balance you’d focus on that. Usually with injuries you’d also have guidance from a Physio or health professional on what exercises to do.
What else might help?
Ice remains useful as long as the area is continuing to swell. After 2-3 weeks if swelling remains you may want to replace ice with heat or contrast bathing. Both will improve the blood supply to the area to help clear swelling. Contrast bathing is using heat for 1 minute, then ice for 1 minute and continuing for 10-15 minutes finishing with heat. In theory this helps to cause blood and lymph vessels to dilate and then contract to pump fluid from the area.
Massage may help by reducing inflammation and pain, avoid aggressive painful massage around healing tissues. A compression bandage or supportive taping can also be used to manage swelling and support the area. Ultrasound may also help the healing process in soft tissues.
Gentle exercise can be used in the sub-acute stage following an injury but it should be done in a pain free manner with a gradual progression and respect to the healing structures. Loading tissues in this way can reduce deconditioning following an injury and help stimulate the healing process and development of collagen.
Injuries that create pain and swelling need to be assessed by your GP, Physio or health professional. Their guidance always supersedes that of general advice on this and other blogs.