Plate 233

Although definitive indications for incision and drainage of infections of the hand vary with the location, duration, extent, and severity of the infection, most localized infections warrant incision and drainage or operative debridement. Particular attention must be paid to patients with immunocompromised conditions that might mask an adequate inflammatory response and delay diagnosis and treatment. Most infections arising on the volar surface of the hand produce maximal swelling on the dorsum; however, dorsal drainage is used only when suppuration presents on the dorsum. If necrotizing fasciitis is suspected, either streptococcal or polymicrobial, immediate and aggressive operative debridement is warranted.

If surgery cannot be performed immediately or the diagnosis of deep infection is uncertain, immobilization, rest, and elevation of the extremity in combination with aggressive broad-spectrum antibiotic therapy are initial treatments. Once the diagnosis of abscess is made, incision and drainage are performed. Patients with comorbidities must be evaluated and treated appropriately, particularly glucose control in diabetic patients.

Various anesthetic blocks can be used depending on the level and extent of anesthesia required. Axillary, brachial plexus, and Bier blocks may be used for complete anesthesia of the forearm and hand. Regional blocks of the median, ulnar, or radial nerve at the wrist can be performed with a high level of reliability. Digital blocks can be performed either through a volar or dorsal approach, taking care to prevent excessive infiltration around the base of the digit, which can cause digital compartment syndrome and threaten circulation. Most surgeons would avoid epinephrine use because of arterial vasospasm that may result in ischemia to the digit. General anesthesia is used for more extensive infections or in cases where regional anesthesia cannot be performed safely.

The patient is placed in a supine position with the involved hand on an arm table.

Routine skin preparation of the hand is performed. Except for minor procedures, a tourniquet set to 250 mmHg is placed on the upper arm. In infectious cases, gravity exsanguination is preferred over active (elastic bandage) exsanguination to prevent the hematologic spread of infection.

Details of Procedure

Immediate drainage is imperative to relieve increased tension and prevent development of osteomyelitis of the distal phalanx. For a deeply situated abscess, the incision can be made longitudinally along the ulnar side of the digit 3-mm volar to the nail edge. Incisions along the radial side of the digit should be avoided to prevent painful scar with pinch maneuvers. Alternatively, a longitudinal incision centered on the volar pad can be performed. Regardless of the approach, blunt dissection volar to the distal phalanx through the septae of the pulp should be thorough, releasing all compartments where infection could reside (Figures 1, 2, and 3). Care must be taken not to enter the tendon sheath. The wound should be copiously irrigated and packed with light gauze and the wound left to heal secondarily.

Details of Procedure

Acute paronychia is the most common infection of the hand. Acute unilateral paronychia requires elevation of the cuticle from the nail at the site of infection (Figure 3). If the infection is advanced or proximal abscess is present, removal of the proximal portion of the nail plate is performed (Figures 4 and 5) and light gauze packing placed to prevent closure of the fold (Figure 6). The entire nail plate may need to be removed in more extensive infection. If necessary to ensure adequate drainage, an incision may be made in the skin below the corner of the nail, placed laterally to avoid damage to the germinal matrix (Figure 3). Recurrent or chronic paronychia should be evaluated for fungal infection and may need marsupialization of the nail plate (Figure 7).

Details of Procedure

The flexor sheaths originate just distal to the distal interphalangeal joint and extend to the palmar flexion crease. The sheath of the flexor pollicis longus continues to the radial bursa and the flexor sheath of the little finger is confluent with the ulnar bursa (Figure 8). For early infections (less than 24 hours) without evidence of abscess, conservative treatment with broad-spectrum intravenous antibiotics, splinting, elevation, and frequent physical examination can be performed. If moderate infection is present, drainage can be performed with a limited incision approach proximally and distally in the sheath to allow for an indwelling irrigation catheter. The proximal incision is transversely oriented at the distal palmar flexion crease and the distal incision is obliquely oriented over the middle phalanx or along with midlateral line to expose the flexor tendon sheaths (Figure 9). Care is taken to prevent injury to the neurovascular bundles. Extensive infection should be approached through lateral midaxial incisions placed ulnar on digits 2, 3, and 4 and radial on the thumb and small finger (Figure 10). For all infections, cultures and sensitivities should be performed with directed antibiotic coverage performed.

Postoperative Care

Dry dressings and early return of motion, usually on the following day, with gradual increase in range of motion, are indicated in uncomplicated felon and paronychia. In tendon sheath infections, antibiotics are continued for a week. Gentle movements are encouraged and increased as tolerated. Elevation of the extremity to heart level will lessen discomfort during the period of immobilization until swelling has cleared. The rehabilitation of the infected hand requires careful supervision.

Details of Procedure

Most abscesses of the interdigital spaces may be drained through incisions placed longitudinally over the dorsal webspace, preventing a painful scar on the volar surface (Figure 11). If the infection is near the volar surface, a second volar incision may be indicated. Midpalmar space infections should be approached volarly in a curved longitudinal incision (Figure 10). Isolated deep infections of the thenar and hypothenar spaces are rare and can be approached through a longitudinal dorsal approach (Figure 11). Parona's space connects the thenar and midpalmar spaces in the distal forearm, just superficial to the pronator quadratus. It can be approached through a longitudinal incision just ulnar to the palmaris tendon (Figure 11). Care should be taken to prevent injury to the median nerve. As in the case for most infections, cultures should be obtained and broad-spectrum antibiotics administered until culture-directed treatment can be implemented.

Postoperative Care

For felons and paronynchia, dressing changes and early return of motion are indicated, usually on the following day with gradual increase in rage of motion. For tendon sheath and deep space infections, antibiotics are continued in a culture-directed manner. Dressing changes are performed several times a day. Irrigation catheters can usually be removed 2 to 3 days after placement. Once overt infection has improved, gentle movements are encouraged and increased as tolerated. Elevation of the extremity to heart level will lessen discomfort during the period of immobilization until swelling has cleared. Frequently, these patients need to be evaluated and treated by dedicated hand therapy specialists to maximize recovery.