If only I knew… Anatomy 101
By Marie-Catherine Bruno, BScPT, Cped(C).
First of all, the lingo
In this first chronicle, we will concentrate on the basics: the medical terms, aka the lingo. We will review some anatomy, and then look at some generic terms used to describe common musculoskeletal injuries. This should give you just enough confidence to read medical columns without feeling lost.
Basic terms of anatomy:
Here we will describe the main parts of the body that are involved in the musculoskeletal system.
- Tendon: the strongest part of the muscle that attaches the muscle belly to the bone. Usually of a whitish colour, you can see them in your T-bone steak! Not to be confused with a nerve as they may look fairly similar to a neophyte.
- Nerve: very delicate and fragile tissue that conducts electricity in your whole body. The nervous tissue runs all in ONE PIECE from your brain to the tip of your toes and fingers. It allows for sensation and reflexes and also brings the electric power to the muscles. The most famous (or infamous should I say) nerve amongst the orienteering and running population is most certainly the sciatic nerve.
- Bursa: little cushion designed to protect bone in areas of high friction (like underneath a tendon) or at high risk of impact due to exposure (like on the knee cap).
- Cartilage: soft and white, you find it where a strong but flexible structure is needed (where bone is too hard and not resilient enough). Example: the tip of your nose, your external ear, the end of your ribs… It basically allows your bony structure some movement. Be aware though, it is not bone! It contains hardly any blood, and therefore does not heal very well.
- Disc and/or meniscus: cushion made of cartilage and/or fibrous tissue to help absorb shocks between bones and also to improve the stability of the joint (their particular shape allows them to fit bones like pieces of a puzzle). Such discs are found in your spine, knees (called meniscus at the knee joint), wrists, jaw, sternoclavicular joint (a joint in the chest where the collarbone, or clavicle, attaches to the breastbone, or sternum) and sometimes (only 30% of the population) in your acromioclavicular joint (a joint in the shoulder where the clavicle joins the acromion, a part of the shoulder blade, or scapula).
- Ligament: very strong band of tissue designed to hold bones together in joints. Ligaments contain a myriad of movement receptors that allow you to know the position of a joint in space (for example, if your eyes were closed and somebody bent your elbow, you would know that your elbow is bent. Also, when you spot a rock on the ground, you don’t have to actually watch your foot to make sure you clear the rock – it all happens automatically). Ligaments are also responsible (along with the joint capsule) for proprioception, the capacity to stabilize and balance a joint (for example: when you are running, every time your foot lands on the ground you must contract the right muscles so you don’t roll over your ankle and collapse the knee).
- Capsule: strong tissue that wraps around your joint to hold the bones together. Ligaments usually lie on top of the capsule to reinforce it. The capsule also provides a sealed environment to keep the joint lubricated by holding fluid in there (called synovial fluid).
Is it a sprain or a strain?
When those tissues get damaged, you are faced with an injury. Depending on what tissue was affected, the injury will carry a different name. If you come to master the lingo of that section, you will certainly impress not only your friends, but also your medical doctor!
- Sprain: a tear (partial or complete) of a ligament. Not to be confused with a strain.
- Strain: a tear (partial or complete), but of a muscle belly or a tendon. Not to be confused with a sprain. (in other words, sprain refers to ligaments and strain to muscles)
- Rupture: a tear (partial or complete), of a tendon or a capsule.
- Tendonitis: inflammation of a tendon. Often due to overuse (repetitive movements), it can sometimes be caused by a direct trauma (example: smashing your elbow on a tree in a hot orienteering pursuit).
- Bursitis: inflammation of a bursa. It can be infectious (bacteria), it can be due to overuse (common at the shoulder with swimmers) or due to a trauma (example: a blow to your ankle bone – who hasn’t spiked themselves at least once?!).
- Neuritis: inflammation of a nerve. Usually due to an irritation (overuse) or due to a compression (tight muscle, decreased joint space, old scar tissue…), it can sometimes be the result of some infection or serious disease.
- Capsulitis: inflammation of the capsule. Usually seen at the shoulder, the cause is still debateable.
- Fracture: break of a bone.
- Dislocation: loss of integrity of a joint – the 2 bones forming a joint are no longer in contact.
- Subluxation: a much more less aggressive form of dislocation where the joint is still together but the 2 bones forming that have partially lost their integrity.
This concludes this short Anatomy 101 presentation. Keep this column handy as we will refer to those terms regularly in upcoming columns.
With that in hands, you should be able to differentiate a sprain from a strain. But nevertheless, both are still very painful and should be avoided at all cost!