Review Question - QID 217417

This patient has flexor tenosynovitis of the right index finger. Early IV antibiotic administration has been shown to correlate most closely with good outcomes.

Flexor tenosynovitis accounts for a significant (2.5-9.4%) portion of all hand infections and is more common with patients who are diabetic, immunocompromised, or have a history of IV drug use. It typically occurs as a result of penetrating trauma to the tendon sheath. If the infection involves the thumb or small fingers, a horseshoe abscess can form as there is a connection between the thumb and small finger tendon sheaths at the level of the wrist. The most common bacteria cultured include MSSA, MRSA, and skin flora like staphylococcus epidermidis, group-A streptococcus and pseudomonas. MRI can be used to assist in diagnosis if the clinical exam is equivocal but flexor tenosynovitis is a clinical diagnosis based on the 4 Kanavel signs. With early presentation IV antibiotic therapy alone may be sufficient, while with more advanced disease formal I&D with either a Brunner open or two-incision technique should be employed.

Hyatt et al. reviewed the diagnosis and treatment of flexor tenosynovitis. They note that thorough history and physical examination by use of the Kanavel signs represent the primary method for diagnosis. They also point out that early administration of antibiotics correlates closely with good outcomes so, in combination with incision and drainage, this remains an important intervention.

Draeger et al. published a review of hand flexor tenosynovitis, which reviewed anatomy, management and outcomes. They note that management consists of early IV antibiotics and surgical drainage. Despite early appropriate management, they find that most patients can expect to have stiffness after infection, with those presenting late having a high risk for other morbidities including amputation.

Figure A demonstrates a right-hand image that shows swelling and erythema as well as slightly flexed posturing of the right index finger indicative of flexor tenosynovitis. Illustration A depicts the four Kanavel signs used in the diagnosis of flexor tenosynovitis.

Incorrect Answers:
Answer 1: Gram-positive cocci including staphylococcus aureus (MSSA & MRSA) are the most common bacteria cultured.
Answer 2: MRI is not necessary for diagnosis as the diagnosis should be clinical.
Answer 4: The index finger tendon sheath does not communicate with the others, therefore, does not contributed to a horseshoe abscess which would be caused by infection in the thumb or small finger.
Answer 5: Either the two-incision angiocatheter technique or a full open Bruner incision may be effectively utilized for incision and drainage these cases.