ABSTRACT
SKIN n Volar skin is thicker, less mobile, and has papillary ridges for grasping. n Dorsal skin is thinner and more mobile, and the subcutaneous tissue contains veins and
lymphatics.
RETINACULAR SYSTEM n Volar fascia
• Anchors volar skin to bone for grasping, in contrast to loose skin on dorsum • Superficial volar fascia: Triangular-shaped fascia attached proximally to PL tendon;
composed of longitudinal fibers, vertical fibers, transverse fibers, and natatory ligaments n Retaining ligaments of fingers
• Stabilize skin and extensor mechanism of digits and support neurovascular bundles Grayson’s ligament: Passes transversely from volar aspect of flexor tendon sheath to
skin1 (Fig. 59-1) Prevents bowstringing of neurovascular bundle during finger flexion
Cleland’s ligament: Passes from juncture of periosteum and flexor tendon sheath to skin laterally (see Fig. 59-1) Lies dorsal to neurovascular bundle
Transverse retinacular ligament: Lateral side of PIP joint, superficial to collateral ligament Prevents dorsomedial
displacement of lateral bands Oblique retinacular ligament
(ligament of Landsmeer): Originates on volar aspect of middle phalanx and inserts on dorsal aspect of distal phalanx Helps coordinate PIP joint and
DIP joint motion
DeeP Fascial sPaces n Potential spaces that can be sites of
infection • Midvolar space Boundaries
Dorsal: Volar interossei and metacarpals
Volar: Volar aponeurosis and flexor tendons of ring, long, and small fingers
Ulnar: Hypothenar septum Radial: Midvolar (oblique) septum
• Thenar space Boundaries
Dorsal: AdP Volar: Index flexor tendon Ulnar: Midvolar (oblique) septum Radial: Adductor insertion and thenar muscle fascia
• Hypothenar space Boundaries
Dorsal: Hypothenar muscles Volar: Small-finger flexor tendon Ulnar: Hypothenar muscles Radial: Hypothenar septum
• Interdigital web space Location of collar button abscess Boundaries
Dorsal: Dorsal fascia and skin Volar: Volar fascia Ulnar: Extensor mechanism and MP joint capsule Radial: Extensor mechanism and MP joint capsule
• Parona’s space Infections can spread to this space from radial or ulnar bursa, or midvolar space. Boundaries
Dorsal: Pronator quadratus Volar: Digital flexors Ulnar: FCU Radial: Radial bursa (containing FPL)
Fig. 59-1 Distal volar and digital fascia.