PYOGENIC FLEXOR TENOSYNOVITIS

Question 1

Pyogenic flexor tenosynovitis definition

Answer 1

Infection of the flexor tendon sheath

Question 2

Extent of flexor sheaths in the hand

Answer 2

1. Flexor sheaths of IF, MF and RF = DIPJ to just proximal to A1 pulley
2. Flexor sheath of LF = DIPJ to as proximal as ulnar bursa
3. Flexor sheath of thumb = IPJ to as proximal as radial bursa
   Radial and ulnar bursae communicate at space of Parona

Question 3

Horseshoe abscess

Answer 3

Abscess involving the flexor sheaths of thumb and LF due to their communication via the radial and ulnar bursae at the space of Parona

Question 4

Aetiology of pyogenic flexor tenosynovitis

Answer 4

1. Penetrating injury to flexor sheath
2. Direct spread from
   - felon
   - paronychia
   - septic joint
   - deep space infection

Question 5

Common microorganisms causing pyogenic flexor tenosynovitis

Answer 5

Staph aureus = most common (75-80%)
Strep pyogenes = more aggressive than Staph, presents within 24-48h
IVDU = MRSA
Immunocompromised incl. diabetics = Gram negative organisms and mixed flora
Human bites = Eikenella
Animal bites = Pasturella multocida
Chronic cases = Mycobacteria

Question 6

Kanavel’s 4 cardinal signs of pyogenic flexor tenosynovitis

Answer 6

Look
1. Diffuse fusiform swelling of digit = sausage digit
2. Flexed posture of digit
Feel
3. Tenderness along flexor tendon sheath
Move
4. Severe pain along flexor sheath with passive extension of digit

Question 7

4 principles of surgical management of hand infections

Answer 7

1. Debridement and irrigation
   - tourniquet without exsanguination
   - use extensile incisions
   - cross flexor creases at 45deg
2. Splinting
   - position of safety = MPs at 90deg, IPs in extension
   - puts collateral ligaments on stretch
3. Antibiotics
   - initially empirical, then directed
4. Early ROM
   - to prevent tendon adhesions

Question 8

4 main complications with pyogenic flexor tenosynovitis

Answer 8

1. Proximal spread of infection
2. Osteomyelitis
3. Pulley or tendon rupture
4. Adhesions and stiffness

Question 9

2 factors to consider in management of pyogenic flexor tenosynovitis

Answer 9

1. Severity of infection
2. Timing of presentation = early vs. established
   Only indication of nonoperative management (splinting and IV Abs) is a mild early infection

Question 10

3 risk factors for pyogenic flexor tenosynovitis

Answer 10

1. Immunosuppressed states
2. Diabetes
3. IVDU