What is a painful arc syndrome?

A "painful arc", is it a "syndrome"?

You could define a painful arc as a painful passage during a movement, active or passive, inbetween two painfree passages.

This is found very often in the shoulder and is considered being a “localizing sign”:

in combination with other tests from the basic examination it gives accessory information about the presumeable localisation of the lesion.

Painful arc in the shoulder

In the shoulder we can find a painful on active elevation or on medial rotation.  Very often that also points in the direction of a chronic "light" subdeltoid bursitis.

>>> 6 reasons for a painful arc

1.  supraspinatus tendinosis, tenoperiosteal
2. infraspinatus tendinosis, tenoperiosteal
3. subscapularis tendinosis, tenoperiosteal, cranial part
4. subdeltoid bursitis "light"
5. acromio-clavicular joint sprain, deep part
6.  biceps caput longum lesion

Of course, in each one of those cases we have to interpret the cluster of positive and negative tests that point in a certain direction.

Painful arc on shoulder elevation

In exceptional cases the painful arc cannot be detected in an active way (e.g. because the elevation movement is too painful), but only in a passive way.  

In that case a severe symptomatic calcification of the supraspinatus might be suspected (that’s an empirical finding).

Painful arc related to spine problems

This can also be found during the straight leg raise test and is a typical finding pointing in the direction of a symptomatic small lumbar internal derangement.

Painful arc on straight leg raise test