Penile reconstruction: combined use of an innervated forearm osteocutaneous flap and big toe pulp

The use of a radial forearm flap has become the most popular method to reconstruct a phallus in recent years. This method of reconstruction, however, is plagued with problems such as urethral fistula and loss of phallic girth as a result of tissue atrophy, rendering a phallic contour that is cosmetically unsatisfactory. We had the opportunity of modifying the technique of penile reconstruction using a forearm osteocutaneous flap to minimize these problems. Specifically, a segment of the big toe pulp is used to reconstruct a glans penis. Sensory restoration in the "glans" and "penile shaft" is restored by coapting the digital and the antebrachial nerves to the penile nerve remnants. A segment of flexor carpi radialis muscle is included in the design of a forearm flap to reinforce the coaptation site of the urethral tract. An arteriovenous shunt is incorporated in the shaft as a mechanism to elicit erection of the penis by compressing the root of the neophallus. We had used these technical modifications in a 51-year-old man who had undergone penile amputation because of cancer. The cosmetic appearance and erotic and tactile sensation in the shaft and glans were proper and satisfactory at the end of fourth year after the surgery. The coital function was also satisfactory.     

Sixty-four cases of thumb and finger reconstruction using transplantation of the big toe skin-nail flap combined with the second toe or the second and third toes

The purpose of this article is to introduce the results of thumb and finger reconstruction using transplantation of the big toe wraparound flap combined with the second toe or the second and third toes. Between August of 1981 and December of 1998, in a series of 64 cases involving 58 patients with digitless hands, either (1) the thumb and index fingers were reconstructed by transplantation of a big toe wraparound flap combined with the adjacent second toe harvested from the ipsilateral foot; or (2) the thumb, index, and long fingers were reconstructed by transplantation of an ipsilateral big toe wraparound flap combined with the adjacent second and third toes. The phalanx of the new thumb was usually an iliac block. The success rate of this series was 92.2 percent. At long-term follow-up, the average static 2-point discrimination was less than 10 mm. The distance between the tip of the new thumb and the new index finger ranged from 6 to 10 cm (average, 8 cm). Opposition action was nimble and forceful. The patients could lift a 6- to 12-kg weight with their reconstructed digits. All patients were satisfied with their new hands and were able to use them in their daily activities. The transplants for reconstructing the thumb and fingers are harvested from the same foot in a procedure known as one-foot donation. Function of the bilateral digitless hand can be recovered with this procedure.     

Small toe muscles for defect coverage

Defects on the sole of the foot are always a major problem. Frequently, these patients suffer from other diseases, such as diabetes mellitus, chronic vascular diseases, or skeletal deformities. Usually, these are full-thickness defects and the bone is exposed. Beside other possibilities, the short muscles of the fifth toe provide a viable muscle flap for coverage of small defects, especially on the lateral side of the foot.     

Combined second and third toe transfer

Historically, restoration of hand function following multiple digital amputation has been unsatisfactory. The evolution of digital reconstruction with toe transfer has enabled surgeons to reestablish prehension in these severely injured hands. A 4-year experience with 26 consecutive combined second and third toe transfers to replace missing adjacent fingers was reviewed in order to delineate the indications and technical considerations and to emphasize prevention of donor-site complications. Combined second and third toe transfer is reserved for adjacent finger amputations proximal to the digital web space with remaining fingers no longer than the small finger. Radial amputations are replaced with contralateral combined toe units, while ipsilateral toes are more ideal for ulnar amputations. Limited dorsal and plantar skin flaps extending only to the midpoint of the first and third digital web spaces allow for direct donor-site closure and uncomplicated healing. Maintenance of the plantar metatarsal arch by avoiding metatarsal shaft osteotomies or bone grafting-shortened metatarsals eliminates potential gait disturbances. When properly applied in selected patients, this single-stage microsurgical procedure can restore prehensile function, improve the appearance of the hand with multiple digital amputations, and preserve near-normal donor-foot function.     

Convergent evolution of lizard toe fringes

Lizard toe fringes are composed of laterally projecting elongated scales and have arisen independently at least 26 times in seven families of lizards. Four different fringe types are identified: triangular, projectional, conical and rectangular. To determine if variation in fringe morphology can be attributed to environmental differences, each independent evolution of a fringe type is identified; correlation of substrate types with evolutionary independent fringe morphologies are then studied. Variation in fringe morphology shows a strong association with substrate type: triangular, projectional and conical fringes with windblown sand; and rectangular fringes with water. Some aspects of fringe morphology may result from differences in functional requirements, and others may have no adaptive significance. This example of convergent evolution points out difficulties inherent to comparative studies of adaptation and underscores the value of broad comparative surveys which provide an alternative to ad hoc adaptive explanations of similarity.