- Anatomy:
- flexor sheath of thumb usually extends from distal phalanx to a point
2-4 cm proximal to volar wrist crease;
- proximal half of tendon sheath is commonly referred to as the radial bursa;
- occasionally proximal half of
FPL sheath is separate from distal sheath,
making them entirely separate sheaths;
- in 80% of patients, the ulnar bursae communicates w/ the
radial bursae;
- this accounts for the horse shoe tenosynovitis;
- Tenosynovitis:
- pus may extend from thumb sheath to proximal end of radial bursae;
- pus in thumb flexor tendon sheath can also lead to infection in carpal tunnel;
- incision:
- extends on ular side of
FPL sheath & distal part of thenar eminence;
- do not to extend incision along ulnar border of thenar eminence proximally
beyond the mid point of first metacarpal;
- this avoids
motor branches of
median nerve;
