CASE                               26                               

A 32-year-old, male patient reports 4 days ago he was fishing in the wilderness when he punctured his long finger with a fishing hook. Over the past 3 days during his trek back, he reports long finger pain with passive extension, fusiform swelling, and pain along the flexor sheath. Flexor tenosynovitis is suspected. He also reports worsening pain in the hand.

Rupture of the flexor sheath and progression of the infection into what space is most concerning?

1. Thenar space

2. Midpalmar space

3. Parona’s space

4. Intermetacarpal space

5. Hypothenar space

Discussion

The correct answer is (B). See below for further discussion.

Which of the following is not one of the borders of the midpalmar space?

1. Oblique palmar septum

2. Volar interossei and 3,4,5 metacarpals

3. Hypothenar septum

4. Flexor tendons to the long, ring, and small fingers

5. The adductor pollicis

Discussion

The correct answer is (E). The midpalmar space is a potential space lying between the thenar and hypothenar spaces. It is bordered by the oblique midpalmar septum radially, the flexor tendons to the fingers volarly, the hypothenar septum ulnarly, and the volar interossei and long, ring, and small metacarpals dorsally. The vertical septae of the palmar fascia provides the distal border, and a thin septum at the distal end of the carpal tunnel is the proximal border. This potential space is essentially a bursa to prevent friction between the overlying flexor tendons, the volar interossei, and metacarpals below. The thenar space is bordered by the adductor pollicis (deep), the thenar skin (superficial), and the oblique midpalmar septum (ulnarly). Rupture of the flexor tendon sheath of the ring and long fingers can extend proximally into the midpalmar space.

Parona’s space is a potential space of the distal forearm overlying the pronator quadratus and lying deep to the FPL and FDP tendons. The thenar space lies ulnar to the midpalmar fascia and is not usually involved with ring finger flexor tenosynovitis rupture. A collar button abscess extends on both the volar and dorsal side of a web space infection.

Which of the following is consistent with midpalmar space infection?

1. Painless with motion of the ring and long fingers.

2. Maintenance of the palmar concavity

3. Dorsal hand swelling

4. Painless palpation of the mid palm

5. Thumb held in abduction

Discussion

The correct answer is (C). Dorsal hand swelling is often present with deep space hand infections, although it is usually painless and without erythema. Abduction of the thumb is typical of a thenar space infection. The palm will be tender with a midpalmar space infection, and the palmar concavity is lost. Pain with the ring and long fingers is expected because they pass over the midpalmar space.

What is the appropriate next step in this patient’s treatment?

1. Elevation, splinting, antibiotics, and observation

2. Dorsal and volar incisions of the hand for drainage

3. Irrigation and debridement through a midaxial incision on the digit and transverse incision at the midpalmar crease

4. Irrigation and debridement through a longitudinal incision overlying the volar finger extending to the palm

5. Irrigation and debridement through FCR approach to the volar forearm

Discussion

The correct answer is (C). Observation and antibiotics are inadequate to treat this progressive infection. A dorsal incision over the hand is unnecessary to adequately drain the abscess. A midaxial incision and transverse incision will adequately drain the flexor sheath as well as the midpalmar abscess. Longitudinal incisions are avoided across flexion creases of the digits and hand to prevent scar contracture and loss of motion postoperatively. An FCR approach is useful to drain an abscess in Parona’s space.

Objectives: Did you learn...?

Describe the anatomy of the midpalmar space?

Pinpoint the physical examination findings consistent with midpalmar space infection?

Describe the correct management of midpalmar abscesses?

CASE                               27                               

A 23-year-old man presents to your office with pain of his fingertip over the past day. He does admit to biting his nails and cuticles, particularly because he is stressed over his upcoming dentistry examinations. He has slight swelling and redness over the ulnar eponychial fold of his index finger. He has tenderness to palpation, but no fluctuance is noted.

What is the diagnosis?

1. Paronychial infection

2. Finger felon

3. Distal interphalyngeal septic arthritis

4. Psoriatic arthritis

5. Herpetic Whitlow

Discussion

The correct answer is (A). This is an infection of the tissues around the fingernail. A history of biting of the nails is typical as it results in a break of the skin barrier, a source of bacteria, and a moist environment with tissue maceration. A finger felon is an infection of the fingertip pulp tissue—the pain, swelling, and redness would be volar in that situation. DIP joint septic arthritis would present with generalized swelling of the distal digit. Psoriatic arthritis often presents with pitting of the nails and nails that separate from the underlying nail bed (onycholysis). A herpetic whitlow would present with vesicle formation.

What is the most appropriate next step in management for this patient?

1. Warm soapy water soaks and oral antibiotics

2. Drainage by elevating the paronychial fold away from the nail

3. Drainage by incising over the point of maximal tenderness with the knife directed toward the nail bed and matrix

4. Removal of the ulnar half of the nail

5. Complete removal of the nail

Discussion

The correct answer is (A). Without clear fluctuance and after a short time course, oral antibiotics and soaks in warm soapy water to promote drainage are often adequate. If fluctuance is appreciated, drainage is accomplished by elevating the fold away from the nail after adequate regional block. Alternately, an incision can be

made over the point of maximal tenderness but should be directed away from the nail fold to prevent nail deformity. Partial or complete nail removal is utilized with more extensive infections often involving the eponychia and opposite paronychia, respectively.

The patient is treated with antibiotics and has a full recovery. He reports that he passed his examinations and has started his clinical rotations for dental school. However, 3 months later he represents with painful small vesicular lesions with a red base affecting his ulnar paronychia surrounding a confluent, large vesicular lesion extending to the proximal phalanx of his thumb.

What is the most appropriate next step in management?

1. Observation

2. Oral antibiotics and warm soapy soaks

3. Drainage of the infection by elevating the paronychial fold away from the nail.

4. Removal of one half of the nail

5. Removal of the complete nail

Discussion

The correct answer is (A). The vesicular lesions are consistent with a Herpetic Whitlow, or cutaneous Herpes Simplex Virus Infection. Dental workers are at a higher risk because of contact with oral herpetic infections. Young children who suck on their fingers and have an oral infection are also at risk. The condition is usually self-limited, but antivirals are used when the condition is not improving, worsening, or very painful. Surgeons will often receive pressure to drain these infections, but surgical drainage is contraindicated as it does not affect the course of the viral infection and can cause significant wound healing problems, or encephalitis via hematogenous spreading.

Objectives: Did you learn...?

Describe the presentation of paronychial infection? Understand its management?

Describe the management of herpetic whitlow?