Hi Guys, welcome to this week’s blog topic - hamstring injuries or specifically hamstring strains or tears.
Let’s get some terminology out of the way first. It’s important to note that a strain and a tear are the same, the terms are used interchangeably to indicate damage to a muscle. The degree of damage is then based on the grade of the tear (read on below). Light, grade 1 tears are commonly referred to as strains, however even light strains cause tearing to some of the muscle fibres and so the term ‘muscle tear’ is the most accurate way to describe the injury.
It’s also important to distinguish between a strain and a sprain. A strain is an injury that happens to a muscle where as a sprain is an injury that happens to a joint. So we can have a hamstring tear or an ankle sprain but we can’t have an ankle strain and a hamstring sprain.
So why do we want to talk about hamstring injuries? Simply put they are one of the most common soft tissue injuries and depending on which research you follow, many articles suggest that they are THE most common soft tissue and sporting injury.
Hamstring tears commonly occur in activities that require sprinting and/or kicking, this includes track athletics, football, netball, soccer, hockey, basketball etc.
What are the Hamstrings? They are a group of 3 muscles (biceps femoris on the outside, semi-membranosus and semi-tendinosus on the inside) that arise from under the glutes, along the back of the thigh and insert just below the knee.
The action of the hamstring muscles is twofold, firstly they act to bend the knee and secondly, they work to straighten the hip. It’s this dual role over the hip and the knee that makes it susceptible to injury.
The majority of hamstring injuries tend to occur in the musculotendinous junction (where the muscle becomes a tendon) of the biceps femoris muscle. They are usually a non-contact injury and generally occur when sprinting.
In order to understand how the muscle tears, we need to have a brief understanding of how a muscle operates. Essentially there are 3 main types of contraction a muscle can perform:
1. Isometric – tension in a muscle but no movement occurs (i.e. flex your bicep)
2. Concentric – a muscle contracts into a shortened state to create a joint movement (i.e. biceps shorten to bring your hand to your shoulder)
3. Eccentric – a muscle contracts as it lengthens to control movement (think of the downward motion of a chin-up, where the bicep lengthens to control your descent)
During a maximal sprint the hamstrings become highly active toward the end of the swing phase, as they contract eccentrically to slow the swinging of the lower leg and control how far we straighten the knee. They then remain active and begin to work concentrically to extend at the hip and help propel the body forward.
It’s at this point that most hamstring tears occur: at the change from an eccentric to a concentric contraction, when the muscles reach their longest point, are maximally activated and must begin shortening again. In this position the demand placed on the muscle is more than it can withstand, and it creates a rupturing to the muscle fibers.
There are three grades which measure the severity of the tearing itself:
Grade 1 (mild) – over stretching of the muscle with minimal tearing actually involved, commonly goes unnoticed until activity is finished, or may be felt at the time but can generally finish the game. Pain may be present during activities such as sitting or walking up stairs. 10 -14 days recovery
Grade II (moderate) – significant tear of the hamstring muscle fibers. Pain and discomfort are more immediate and strength and fatigue is present, unable to finish the activity due to pain. Contraction and stretching are painful and is usually sore when touched locally. 6-8 weeks recovery
Grade 3 (severe) – complete rupture of the hamstring. Can often be seen by the naked eye, due to a lump of muscle followed by a depression where the muscle is torn. A sharp pain is felt locally immediately, followed by immediate dysfunction and weakness with swelling and bruising (usually extensive) over the next 48 hours. Surgery may be recommended to repair the hamstring, particularly if it has been torn off the bone. 12+ week’s recovery
Predisposing factors to hamstring tears include: age, previous injury, poor flexibility, poor strength or fatigued muscles, lumbopelvic dysfunction such as an anterior pelvic tilt, stiffness through the lumbar spine, inadequate warm up and trying to do too much too soon.
A well-rounded assessment and treatment program needs to first assess the grade of the tear. Initial management should include pain reduction (using the Rest Ice Compression Elevation regime), we can argue the benefits of ice on another day, but let’s agree that sending it numb will give some pain relief.
Followed by light pain free stretching, as tolerated to achieve pain free ROM as soon as possible. Manual therapy including dry needling, soft tissue release and myofascial release is also beneficial as is freeing up the lower back.
Stretching sounds like a strange activity to do early on, given that the injury occurred by overstretching the muscle. The reason we want to stretch early on is, that as scar tissue is formed to mend the torn muscle, it is initially quite pliable. We want to put a mild stress through this so that it realigns with the rest of the muscle (rather than becoming a hard lump) and minimising the risk of reinjuring the area.
Once full range of movement has been regained we want to strengthen the muscle as much as possible by engaging in a targeted strength program, (P.S. the latest advice is that if you’re not doing Nordic curls as part of your hamstring rehab you are wasting your time), this is followed by a return to run program and then a return to sport.
As always we believe prevention is better than cure, so here are 3 tips to prevent hamstring injuries in the first place:
1. Make sure you maintain good mobility through your lower back – excessive low back stiffness place increased strain through the hamstrings, predisposing them to injury.
2. Engage in a good warm-up and include stretching, before and, more importantly, after exercise
3. Maintain good strength in your hamstrings, this will help with your back mobility as well.
If you do experience any of the symptoms mentioned above or have a lot of back stiffness and are thinking about getting back into running sports, then consult your healthcare practitioner sooner rather than later to assess your risk of hamstring injuries.
So that’s a brief overview of how hamstring injuries can occur, If you have questions or comments feel free to e-mail us at firstname.lastname@example.org and we will happily answer them for you.
If you think you may already be suffering from hamstring or low back pain and want relief now, then call us on (08) 9486 8653 and we will arrange an appointment for you.