What are muscle injuries ?
Muscle injuries are the most common winter sport injuries. They lead to significant time off sport and can also impact on the rest of your daily life or job.
In this post we will talk about the different types of muscle injuries and in the next we will go into how they are treated and can best be prevented.
Muscle injuries can be divided into 2 main categories depending on how the injury was sustained.
Indirect muscle injuries
Indirect muscle injuries are commonly termed muscle strain or muscle tears. They are called indirect injuries because they usually occur in a non contact situation – that is without impact with another player. They are common in athletics and contact sports that require sprinting, stopping and starting (pretty much all contact sports!). They are caused by a sudden forced lengthening of a muscle while it is powerfully trying to contract. This can occur while sprinting, changing direction or suddenly slowing down. You will feel a sudden pain and then tightness of the involved muscle – you may or may not feel a tearing or giving-way sensation.
The muscles most often injured in this way are the ones that pass over 2 joints, are used to slow down the player and contain fast twitch fibres – that is the power muscles. In football the hamstrings (at the back of the thigh), the adductors (inner thigh), quadriceps (front of thigh) and calf muscles are the most commonly injured in this order.
Indirect muscle injuries can be divided into 3 grades. These grades are based on the severity of the injury and can give an indication of how the injury should be managed and how long healing is likely to take.
Grade 1 Indirect Muscle Injury
With a grade 1 injury less than 5% of the muscle fibres are torn and the muscle fascia that surrounds the muscle is intact. There is likely to be some tenderness in a specific spot on the muscle but your physiotherapist shouldn’t be able to feel a gap and the muscle should be almost as strong as the other side. The muscle may feel tight when stretching and there may be a little amount of pain when it is at a fully stretched position.
Grade 2 Indirect Muscle Injury
A grade 2 indirect muscle injury is where there is an appreciable tear in the muscle. A moderate number of fibres will be involved – up to 50% and the muscle will be much weaker than the other side. Bruising, swelling and a palpable gap in the muscle may be noticeable but this can depend on how deep the tear is. A deep but large tear may not look bruised or swollen initially – you may notice swelling or bruising remote from the injury up to weeks later if it has stayed deep till gravity brings it to the surface so you shouldn’t go on whether you see bruising or swelling to determine how sever your injury is. The fascia remains intact.
Grade 3 Indirect Muscle Injury
A grade 3 indirect muscle injury is a complete tear of the muscle or more commonly the muscular tendon unit with or without retraction of the muscle. The muscle will not be able to provide any tension. In some areas of the body these are harder to identify than you would imagine because other muscles in the area can take over some of the work so it is always best to consult your physio no matter what grade of indirect muscle injury you suspect you have.
Direct Muscle Injury
A direct muscle injury is caused by direct muscle trauma caused by a blunt external force – such as another player or a piece of sports equipment – think hockey ball to the thigh. The force causes a diffuse haematoma/ contusion resulting in pain and loss of motion. A “corked thigh” is an example of this type of injury. A lump and or bruise may be present and the area will likely feel hard and tender. Care should be taken to rest, ice and gently compress and visit your physio as though it can be tempting to play on contusions can lead to more serious conditions such as acute compartment syndrome.
Delayed Onset Muscle Soreness
Delayed Onset Muscle Soreness or DOMS should not be confused with Indirect or direct muscle injuries. DOMS occurs several hours after unaccustomed muscle activity. It is usually at its worst 48hrs after exercise and will resolve within a week. It is caused by acute inflammation but is a diffuse muscle response. Muscles will feel tight and sore especially after periods of rest. The soreness often eases a little with gentle activity but may come back again after a short rest when you first get up. The old suddenly can’t get up off the couch scenario.
So this is the low down on types of muscle injuries. Next up we will look at how we treat these common injuries, what to look out for before starting back up with your exercise and how to try and prevent getting a muscle injury in the first place.
Reference: Mueller-Wohlfart et al 2012 BJSM 10.1136/bjsports-2012-091448