{'fraction_non_alphanumeric': 0.02119460500963391, 'fraction_numerical': 0.007156619873382879, 'mean_word_length': 4.651632970451011, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A reverse dorsoradial pedicled flap from the thumb for a soft tissue defect in the finger

Several options are available to cover a skin deficit in a digit. The choice largely depends on the size and location of the defect, as well as the experience and personal preference of the surgeon (Tang et al., 2014). When multiple fingers are affected by severe injury, the treatment options become more limited. Pedicled and free flaps are the main alternatives. However, free flaps cannot be recommended for treatment in patients with a history of smoking, or in old or diabetic patients. We describe a reverse dorsoradial pedicled flap from the thumb that is useful in the above-mentioned situations. The reverse dorsoradial pedicled flap has been modified from the reverse dorsoradial flap of the thumb. Figure 1 is a schematic diagram of the operation. The entire dissection procedure is carried out under axillary block with pneumatic tourniquet control. The incision is made on the radial aspect over the first metacarpal, following the route of the dorsal radial digital artery, originating from the snuffbox to the middle third of the radial aspect of the proximal phalanx (i.e. the pivot point) (Moschella and Cordova, 2006). The skin island lies over the course of the dorsoradial artery and its outline is made slightly larger than the defect size (Hrabowski et al., 2010). The flap is dissected from proximal to distal, and one branch of the superficial radial nerve is dissected in the flap. A lazy-Z incision is made across the metacarpophalangeal joint from the distal end of the flap to the pivot point. The dorsoradial digital artery, a few dorsal veins and a branch of the superficial radial nerve are included in the pedicle. After the whole flap has been elevated and rotated, the tourniquet is released to confirm the circulation of the flap. The pedicle is reversed, and the flap inserted into the defect area with several loose stitches. The nerve in the flap is sutured to the nerve in the defect area if possible. Most donor sites can be sutured directly or covered with a full-thickness skin graft. The pedicle is divided 3 weeks later. Active and passive range-ofmotion exercises are encouraged thereafter. There are some useful additional tips. First, the position of thumb and the injured finger should comply with two basic principles: the distance between the pivot point and the recipient area should be as small as possible and patients should feel relatively comfortable with the position. External fixation is recommended to keep the two digits in the right positions. Second, the pedicle can be dissected to be as wide as possible to increase the blood supply and ensure venous return, because the pedicle does not need to be inserted into the recipient area. Third, the pedicle should be covered with a thin skin graft. Remote pedicled flaps usually restrict the mobility of the large joints. The reverse dorsoradial pedicled flap from the thumb not only provides a large stable area of sensate skin coverage, but also reduces donor site deformity and does not affect the motion of large joints. Although the thumb and injured finger must be immobilized for 3 weeks, the range of motion can return to normal through exercises. Figure 2 shows the final outcome in one case who obtained 4.56 g with the Semmes–Weinstein monofilament test and 5 mm in the static 2-point discrimination test (3.84 g and 5 mm, respectively, on the contralateral side), which is a satisfactory outcome. We believe the reverse dorsoradial pedicled flap is a reliable option in specific conditions. Figure 1. Operative diagram.