Medical Terminology

While I understand that most people here aren't interested in taking a medical degree I've had to strike a balance between using jargon which is sometimes difficult to learn but always clear and accurate and using more common language which most are already familiar but tends to be more vague. I've drawn a line that will have gone too far for some and not far enough for others but one that I feel strikes the balance I'm after.

As TuneUp is a project that you won't be taking on lightly I'm going to expect a minimum level of commitment and as part of that ask you to learn a few terms. Initially you'll find yourself coming back to these pages regularly but you'll pick it up eventually, it's not rocket science.

Anatomical references

Throughout the program you'll find terminology that accurately describes certain positions. The common front/back, top/bottom, side/middle descriptions work well enough for someone standing in an anatomically neutral position, but we need terms that are still clear when we change shape.

3D


We reference particular locations on the body in a three dimensional space. At school you learned to do this using a graph with three axes labelled x, y and z. We won't be measuring distances but we will be moving around in the three planes: xy, yz and xz

The Transverse Plane (xy)

The Transverse PlaneThe Transverse Plane
By dividing the body along the transverse or xy plane we can refer to points closer to the head as superior and those closer to the feet as inferior. When you're standing on your feet like this superior is the same as higher and inferior as lower but if I was standing on my head, or lying on my side, these common terms would not be clear enough.

So in this photo my guitar is superior to my knees and my sandals are inferior to my belt, simple.

The Coronal Plane (yz)

Coronal PlaneCoronal Plane

Standing in the usual position The Coronal, or Frontal Plane, distinguishes between the front and the back of the body. We refer to the region at the front as anterior and behind as posterior.

My guitar here is anterior to my spine which is posterior to my hands

The Sagittal Plane (xz)

The Sagittal PlaneThe Sagittal Plane
So the only one left divides the body in half straight down the middle when you're looking front on. This plane enables us to refer to points as being closer or further from the midline. If something is away from the midline we refer to it as bing lateral and if it is closer to the midline we say that it is medial.

In this picture then my right hand is medial to my right elbow while my left shoulder is lateral to my head. Notice too that in this photo I've positioned this smaller auditorium guitar so that my left hand is way too low, this is drawing my shoulder down and my head to the left.

To summarise

  • Superior is toward the head and posterior is toward the feet.
  • Anterior is toward the ventral side (the front when we're standing) and posterior is toward the dorsal side (the back).
  • Lateral is away from the midline and medial is toward the midline.
  • Two more that haven't been addressed yet are proximal, which means closer to the torso and distal which means further along the extremeties. They are more useful when referring to the limbs.

Movements


Once we know how to accurately refer to the points within the body in a three dimensional space we need to be able to talk about how they get into these positions, how the joints move to change our shape. Again it is important to remove any ambiguity so we refer to these movements as occurring at joints, not limbs. Shoulder flexion is more precise than arm flexion or even upper arm flexion, it tells us where the movement is happening. Rotation is an exception, often referred to as a limb rotating at a particular joint.

Definitions

  • Flexion is the movement of the limb in the sagittal plane away from the neutral position. Standing with your arm by your side and raising your entire arm directly in front of you is shoulder flexion. With your shoulder still and your elbow bent it would be elbow flxion. Bringing your knee up behind you is knee flexion. Bending your whole body forward is flexion of the spine. I'm sure you can think of a few more, the defining aspect of flexion is that it happens in the sagittal plane, the one that splits the body left/right.
  • Extension is the movement back toward neutral from a flexed position. So bringing the arm back down is extension, straightening the spine again is extension. Hyperextension is the continuation of this movement past the neutral position so if you arch your back it is being hyperextended.
  • Abduction happens in the frontal plane and refers to a movement away from the midline. Keeping your arm straight and taking it out to your side is abduction. Spreading both arms and legs into a star shape is abduction of the shoulder and the hip joints respectively.
  • Adduction (note the 'add') is bringing the limb back in toward the midline. Moving across the midline is also referred to as adduction.
  • Rotation refers to movement around a central axis. The spine rotates around it's own axis when we turn to one side or rotate the neck. The arm rotates around an axis roughly in line with the shaft of the humerus during rotation at the shoulder joint.
  • Medial rotation refers to the rotation of a limb toward the midline. Your right humerus (upper arm) has to medially rotate at the shoulder to bring your hand into your guitar
  • Lateral rotation refers to rotation away from the midline. Your left humerus rotates laterally at the shoulder when you need to fret high up on the neck.

Of course these movements rarely happen in isolation and throughout the program I refer to them in combinations. For example:

To reach your right hand around to your guitar the shoulder has to do a few things. Firstly you can see that it is abducted away from the midline. It is also slightly flexed, in front of the body to reach over the width of the guitar. The elbow is also flexed and the upper arm has had to rotate medially at the shoulder to bring the hand down on to the guitar.