Criteria of Normalcy
A set of criteria which dictate the physical features of a 'normal' foot (e.g arch height, alignment etc)
CT Scan
Computerised Tomography - essentially several beams of X-Ray from many different angles. Being far more detailed than X-Rays, 3D images can be produced - particularly useful for more complex skeletal investigations.
Force
Forces are what make the human body (or any object for that matter) start moving, change direction or stop moving. Forces the muscles and tendons of the body have to generate, or are subjected to, can vary in nature (compressive, tensile, torsional/rotational etc). If these are at pathological levels then the force must be altered/reduced to bring about any change in pain levels or symptoms.
Impulse
An impulse occurs when a force acts over an interval of time.
Insidious
Having a gradual/cumulative effect. Usually developing so gradually it is likely to be well established before becoming apparent.
Kinematics
This describes the motion or movement of objects. With respect to the human body, in particular the lower limb, it is essentially the visual alignment. Often best assessed with video gait or motion analysis.
Kinetics
This is the area which describes or investigates the forces which drive motion (or kinematics). More and more research is suggesting this is far more important than kinematics with respect to pain and symptom resolution.
Moment
This term is preferred now to torque although they are sometimes still used interchangeably. Essentially it is the measure of tendency to produce a motion about a point or axis. For example a pronation moment across the sub talar joint axis.
MRI
Magnetic Resonance Imaging - a medical imaging technique used to visualise internal structures of the body. Generally a very detailed image with very obvious differences between normal and abnormal tissue being evident. No potentially damaging x-ray or ionising radiation is employed as it is in X-Ray and CT imaging.
Newtons First Law
'A body stays in a state of rest or uniform motion unless acted upon by an external force'. Also sometimes referred to as the law of inertia. Put simply - force starts things moving, changes their direction once they are moving and ultimately stops them moving.
Newtons Second Law
'The net force on an object is equal to its mass multiplied by its acceleration'.
Newtons Third Law
'For every action there is an equal and opposite reaction'. This basically suggests that all forces are interactions - for example ground reaction force in a runner (how hard you hit the ground and how hard it hits you back at the same time).
Paradigm
A theoretical framework. A generally accepted perspective of a particular discipline at a given time.
Pathological
Damaging or symptom causing.
Plantar Pressures
Assessment of particular areas of the sole of the foot which may be under significant load at various times during the gait cycle. Often a cursory prediction of this can be made when considering shoe wear marks or areas of callosity on the foot. In-shoe pressure measurement offers a more quantitative analysis of how pressure is distributed.
Pronation
A complex triplanar movement consisting of foot abduction, eversion and doriflexion (when weightbearing). Put simply the inward rolling of the foot.
Sub-clinical
Undetected.
Subject-specific
An individual response to an intervention. Different people react differently to the same things.
Sub Talar Joint
The articulation between the talus bone and the calcaneus (heel bone). It is across this joint that triplanar motions such as pronation and supination moments occurs, and not the ankle joint as occassionally and mistakenly thought.
Supination
A complex triplanar movement consisting of foot adduction, inversion and plantarflexion (when weightbearing). Put simply the outward rolling of the foot.
Tendinopathy
Usually occurs following repetitive loading, it is generally described as a soreness or discomfort, often quite stiff and at its worst following activity. Most chronic (long term) tendon issues tend to be more of a focal degeneration (tendonosis) rather than the previously thought inflammatory involvement ('tendinitis')
Viscoelasticity
A tissue which is viscoelastic exhibits both plastic (viscous) and elastic properties. Therefore it will deform or change shape under load and return to its original shape (elastic), but it may also deform permanently if loaded beyond this range (plastic). Imagine a rubber band as an example.
X-Ray
A simple diagnostic image taken in one plane usually used to identify any potential bony issues such as fractures, stress fractures (not always visible on x-ray) or to investigate the status of a joint or confirm the presence of arthritic changes.