Pyogenic flexor tenosynovitis - epidemiology, causes, Kanavel signs, imaging, treatment
Pyogenic flexor tenosynovitis is a bacterial infection of the flexor tendon sheaths in the hand. It is a serious condition that requires prompt medical attention. Here are the key aspects of the condition:
Causes
**Bacterial Infection**: Commonly caused by Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (MRSA), but can also be caused by other bacteria like Streptococcus species.
**Injury**: Often results from a penetrating injury to the finger, such as a cut, puncture wound, or bite.
Symptoms
**Kanavel's Four Cardinal Signs**: These are the hallmark signs of pyogenic flexor tenosynovitis:
1. **Finger held in slight flexion**: Due to swelling and pain.
2. **Fusiform (uniform) swelling of the finger**: Swelling that is uniform along the length of the finger.
3. **Tenderness along the flexor tendon sheath**: Pain along the course of the tendon.
4. **Pain with passive extension**: Significant pain when attempting to straighten the finger passively.
Diagnosis
**Clinical Examination**: Based on the characteristic signs and symptoms.
**Imaging**: Ultrasound or MRI can help confirm the diagnosis but is not always necessary.
**Laboratory Tests**: Blood tests, including complete blood count (CBC) and inflammatory markers like CRP and ESR, may be elevated. A sample of fluid from the tendon sheath can be cultured to identify the causative organism.
Treatment
**Antibiotics**: Empiric broad-spectrum antibiotics are started immediately and later tailored based on culture results.
**Surgical Intervention**: Often required to drain the infected sheath. This can be done through open or percutaneous techniques.
**Hand Therapy**: Post-surgical rehabilitation to regain function and mobility of the affected finger.
Prognosis
**Early Treatment**: If treated promptly, the prognosis is generally good, and most patients recover full function.
**Delayed Treatment**: Delays in treatment can lead to complications such as tendon rupture, spread of infection, or chronic pain and stiffness.
Prevention
**Prompt Treatment of Hand Injuries**: Any penetrating injury to the hand should be cleaned and assessed by a healthcare professional.
**Hand Hygiene and Care**: Proper wound care and hygiene can help prevent infections.
If you suspect you have pyogenic flexor tenosynovitis, it's crucial to seek medical attention immediately to prevent complications and ensure proper treatment.