When the radiological signs are minimal in patients with a painful carpal syndrome involving the trapeziometacarpal joint (TMCJ), selective articular denervation can be proposed as an alternative after failure of conservative treatment. Results have been variable, sometimes disappointing, suggesting the anatomic basis of denervation should be revisited. The purpose of this work was to study the nerve supply to the TMCJ in order to acquire the indispensable elements necessary for performing effective selective articular denervation.

This anatomical study was performed by dissection under magnification (4.5-x350) of 15 upper limb cadaver specimens. The median nerve, its thenar and volar cutaneous branches and the terminal sensitive branches of the radial nerve were dissected. Articular branches to the TMCJ were carefully identified. Histological samples were taken to verify the neurological nature of the elements dissected.

All TMCJs dissected exhibited radial and median nerve supply. Branches of the median nerve predominated in number and caliber. The volar cutaneous branch gave rise to articular branches in eleven dissections and the thenar branch gave rise to articular branches via a retrograde arciform trajectory between the short abductor and the opponens digiti pollicis in thirteen. For five dissections, the TMCJ branches arose directly from the median nerve within the carpal tunnel. At histological analysis the dissected elements were identified as nerves.

There have been few anatomic studies concerning the nerve supply of the TMCJ. Unlike the findings reported by Cozzi in 1960, we did not find the dorsal sensitive branch of the radial nerve to play an exclusive or preponderant role in the innervation of the TMCJ. The median nerve supply to the TMCJ appeared to be more significant, particularly for the volar cutaneous and especially thenar branches.

Total and definitive selective denervation of the TMCJ appears to be a most difficult procedure which would require a very wide access and extensive dissection, including the thenar branch which would raise the risk of significant complications.