Passive movements indicate what can be achieved when the examiner moves the fingers. Loss of movement is expressed as a "deficit" and indicates joint stiffness. The presence of normal movement does not necessarily mean that the finger functions normally as there may be loss of muscle action due to denervation, tendon division or tendon adhesion.

Active movements are what the patients can achieve themselves. Any difference between active and passive movement is expressed as a "lag" and usually indicates loss of tendon glide or function.

There are a number of ways of assessing loss of movement in the fingers.

• Individual Joint Motion(degrees)
• Movement Deficits (Flexion and Extension Deficits)(centimetres)
• Total Active Motion (TAM)(degrees)

Each can be used to calculate the percentage functional loss in a finger. For example, a TAM of 175º represents a 35% loss of total digital motion ((270-175)/270º).

More detailed charts are available which also take into account the range as well as the amount of motion. The chart below is for PIPJ movement. It can be seen that 32% of the finger dysfunction in the example above is due to the PIPJ stiffness (5+27% due to the losses of extension and flexion respectively).

The impact of total loss of movement (ankylosis) varies according to the position. A stiff joint in the "position of function" can still be of some functional use. The chart above indicates that a finger with an immobile PIPJ at 40º is equivalent to 50% loss of finger function.

The same types of calculations are made for thumb and wrist motion to enable full assessment of stiffness in the hand

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