Cruciform part of fibrous sheath of digit of hand

Looks like

Thin crossing fibres in the fibrous sheath over the finger-bending tendons, between the stronger ring-shaped pulleys.

What it does

Hold the tendons against the bone while letting the finger bend.

Keeping it well

Tendon sheath infection causes a swollen, bent, painful finger: urgent care.

Related conditions

• Carpal tunnel syndrome
• De Quervain's tenosynovitis
• Dupuytren's contracture & trigger finger
• Ganglion cyst
• Juvenile idiopathic arthritis
• Pseudogout (calcium pyrophosphate disease)
• Raynaud's phenomenon
• Repetitive strain & overuse injury
• Rheumatoid arthritis