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Subchondral
The word 'subchondral' is an adjective referring to the layer of bone immediately under the articular cartilage.
Subchondral drilling
Subchondral drilling is a surgical procedure where small holes are drilled through damaged joint cartilage into the bone marrow of the underlying bone.
Subluxation
Subluxation is when the bones of a joint nearly dislocate, but not quite, and then return to a normal position, eg patellar subluxation.
Sudek's atrophy
Sudeck's atrophy is an old term to describe tissue wasting secondary to complex regional pain syndrome.
Sulcus angle
The sulcus angle is a measurement of the steepness of the walls of the groove in which the kneecap rides (the trochlear groove). Page updated March 2024 by Dr Sheila Strover (Clinical Editor)
Superficial peroneal nerve
The superficial peroneal nerve is the superficial branch of the common peroneal nerve.
Superior
Superior is a positional word, meaning 'above'.
Suprapatellar
Suprapatellar is a positional adjective describing something to be 'above the patella' (kneecap). Page updated November 2023 by Dr Sheila Strover (Clinical Editor)
Suprapatellar bursa
The suprapatellar bursa is an extension of the joint cavity above the kneecap.
Suprapatellar plica
A suprapatellar plica is a fold of joint lining - possibly an embryonic remnant - that stretches across the joint cavity in the pouch above the kneecap. Page updated June 2024 by Dr Sheila Strover (Clinical Editor)