Fascial spaces in the handFascial spaces in the hand

In the olden days, the palm is said to be containing a mid palmar space and a thenar space where pus

can be accumulated.

This view is discarded now.

Mid palmar spaceMid palmar spaceThenar spaceThenar spacePulp spaces of fingersPulp spaces of fingersWeb spacesWeb spacesSub cutaneous space and Sub cutaneous space and Sub aponeurotic space on the Sub aponeurotic space on the

dorsumdorsum

Palmar aponeurosisPalmar aponeurosis

Palmar aponeurosis and septaPalmar aponeurosis and septa

M L

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TS of left hand

Thenar space

•The subcutaneous fat that constitutes the tips of the fingers is loculated by fibrous septa and occupies a closed pulp space which is liable to infection (whitlow) from a penetrating wound.

whitlow

This may be followed by the damageto the distal phalanx

owing to the interruption of its blood supply.

Fibrous flexor sheathsFibrous flexor sheaths

Thick fibrous arches with Thick fibrous arches with cruciform ligaments cruciform ligaments convert the concavity of convert the concavity of metacarpals and metacarpals and phalanges into tunnels phalanges into tunnels and protect the flexor and protect the flexor tendons from slipping.tendons from slipping.

Inside these tunnels the Inside these tunnels the tendons are enclosed in tendons are enclosed in synovial sheaths calledsynovial sheaths called

““digital synovial sheaths” digital synovial sheaths”

Digital synovial sheaths Digital synovial sheaths

As the digital flexor tendons As the digital flexor tendons pass throughpass through

the carpal tunnel they are all the carpal tunnel they are all enclosed in a single (common) enclosed in a single (common) synovial sheath.(synovial sheath.(ulnar bursaulnar bursa))

The FPL has its own synovial The FPL has its own synovial sheath.(sheath.(radial bursaradial bursa))

Note the continuity between th little finger’s digital sheath with the common sheath

“Dupuytren's contracture” of one or more fingers, especially the little and ring fingers, is commonly attributed to thickening and shortening of the palmar aponeurosis.Its causation is not really understood.

Space of paronaSpace of parona

The common synovial sheath The common synovial sheath extends in to the lower extends in to the lower forearm into a space called forearm into a space called “space of parona”(limited “space of parona”(limited proximally by the radial proximally by the radial attachment of FDS)attachment of FDS)

Untreated infection of the synovial sheaths can impair hand function

infection of the synovial sheaths of the thumb or little finger may spread readily into the palm and even into the forearm(space of parona)

Spaces on the dorsumSpaces on the dorsum

Subcutaneous space lies just under the Subcutaneous space lies just under the skin.skin.

Sub aponeurotic space lies deep to the Sub aponeurotic space lies deep to the extensor tendons.extensor tendons.

Infections from fingers and palm can Infections from fingers and palm can spread to these through lymphatics.spread to these through lymphatics.

The Z-position of the hand, produced by the interossei and lumbricals

Claw hand, due to paralysis of the interossei and lumbricals (following lesions of the ulnar nerve). The unopposed extensor and flexors produce the opposite of the Z-position.(extension at M-P joint and flexion atI-P joints)

(Flexion at M-P joints and extension at I-P joints)

Other clinical aspectsOther clinical aspects

Abd.pol.longus and Abd.pol.longus and ext.pol.brevis run in ext.pol.brevis run in the same synovial the same synovial sheath which rubs sheath which rubs against radial styloid against radial styloid process and this process and this could lead to could lead to tenosynovitis and tenosynovitis and may impair may impair movements.movements.

Hand at rest (for immobilization)