subluxation
Pronunciation: sub-luk-SAY-shun
A partial or incomplete dislocation of a joint, in rehabilitation most commonly referring to inferior displacement of the glenohumeral (shoulder) joint following stroke-related hemiplegia.
Full Definition
Subluxation differs from a full dislocation (luxation) in that some articular contact is maintained between the joint surfaces. In stroke rehabilitation, glenohumeral subluxation develops when flaccid or weak shoulder musculature fails to maintain the humeral head in the glenoid fossa, causing it to slide downward under gravity. It is assessed clinically by palpating the gap below the acromion and may be measured radiographically in finger-widths. Editors should not confuse subluxation with 'shoulder subluxation' in the chiropractic sense, which carries different clinical connotations; the term should be used precisely in clinical rehabilitation copy to indicate a partially displaced joint rather than any looseness or instability.
Usage
Usage note: Distinguish clearly from 'dislocation' (complete loss of joint contact). In stroke rehabilitation, 'shoulder subluxation' almost always refers to the glenohumeral joint unless otherwise specified.
In Context
- "A two-finger-width glenohumeral subluxation was identified on the hemiplegic side during the initial shoulder assessment." — Stroke rehabilitation physiotherapy report
- "The editor queried whether 'subluxation' or 'dislocation' was intended, as the radiology report described full loss of joint congruence." — Manuscript copyediting query