Infection of the finger is common, and it can vary in
severity. Serious infection of the fingers will require urgent surgical care.
Felon is a deep infection of the soft pad, or pulp, of the
fingertips. It is usually the result of a puncture wound. Swelling or pus is trapped
in the small compartments of the pulp or the tip of the finger. Symptoms
include unusual redness or swelling, firm swelling, throbbing pain at the tip
of the finger, or visible yellowish area of puss. If the infection goes
untreated, it may lead to severe symptoms such as skin necrosis, flexor
tenosynovitis, osteomyelitis, and arthritis of the distal interphalangeal
joint. Surgery is the usual treatment in the form of incision and drainage of
the felon. If there is no foreign body in the finger, you will do the midaxial
incision or the “J shaped” incision, and you will leave the wound open. If
there is a foreign body present, such as a splinter or a thorn, you will do the
volar longitudinal incision. Try to avoid doing the “fish mouth” incision; it will
lead to unstable finger pulp.
Symptoms of paronychia include swelling, redness, puss
formation, and pain in the soft tissue around the nail plate. Treatment is
antibiotics if the infection is caught early. Surgery is the usual treatment.
Incision and drainage with or without partial nail removal for subungual
abscess.
Herpetic Whitlow is a painful infection caused by the herpes
simplex virus that usually affects the fingers or the thumb. It is seen in
dentists, respiratory therapists, anesthesiologists, and toddlers (children who
suck their thumb). Symptoms include swelling, tenderness, redness, fever,
swollen lymph nodes, burning pain, and vesicle formation on the finger. It can
be grouped together with inflammation and redness at the base of the finger.
The fluid in the vesicle is usually clear (not purulent). The infection is
self-limiting. Conservative treatments include antiviral treatments applied to
the skin (acyclovir). Antibiotics are not used unless secondary infection is
present. Do not do surgery, surgery can make the situation worse.
Flexor tenosynovitis is a relatively common infection of the
hand usually caused by Staphylococcus aureus. It usually occurs due to prior
penetrating trauma and infection. The index, middle, and ring fingers are most
commonly affected. Symptoms include painful swelling of the finger that hurts
worse with motion. Flexor tenosynovitis has Kanavel’s four cardinal signs:
uniform swelling of the entire finger (fusiform swelling, finger looks like a
sausage), the finger is flexed, intense pain when attempting to straighten the
finger (occurs early), tenderness along the course of the tendon sheath (most
important sign). If the infection is caught early, treat with IV antibiotics.
If the infection is severe, do early open drainage of the infection to avoid
skin loss, tendon necrosis, and osteomyelitis. Surgical incisions used to drain
the flexor sheath infection. Use a midaxial or Bruner incision. Use two small
incisions, one proximally at A1 pulley and one distally at A5 pulley. Use an
angiocath for irrigation. Give culture specific IV antibiotics. Infection may
spread from the tendon into the deep palmar space or into the Parona’s space in
the forearm. The little finger communicates with the ulnar bursa. The thumb
communicates with the radial bursa. The radial and ulnar bursa communicate
proximal to the carpal tunnel. Infection may travel from the little finger into
the ulnar bursa to the Parona’s space. Infection can also travel from the thumb
into the radial bursa to the Parona’s space. Infection may cause “horse shoe”
tenosynovitis. Infection travels from the thumb through the radial bursa to the
ulnar bursa infecting the little finger. May need combination of incisions for
drainage.
