Tumors of the nail and nail bed

This article reviews the tumors that most frequently affect the nail and nail bed. Clinical appearance, histopathology, differential diagnosis, and treatment are discussed.     

Half-and-half nail

Clinical and Experimental Nephrology -     

Vascularized nail flap vs. free nail graft

Summary With recent improvements in microvascular surgery, the vascularized nail flap procedure has had considerable success. On the other hand, free nail graft without microvascular anastomoses is still used but little has been published to make a comparison between these two procedures. Thus, it is not known which is the better procedure. In the past, hand nail defects in 12 patients have been reconstructed by the free nail graft procedure and in four patients by vascularized nail flap procedure. In this article, the free nail graft is compared with the vascularized nail flap and the merits and demerits of both techniques are presented. Requests for reprints: T. Endo, M.D.     

Similarities between a conjoined nail and the palmar nail syndrome

The congenital palmar nail syndrome consists of a triad of palmar nail, absent finger flexion and abnormalities of the distal phalanx. There are two main theories about the pathogenesis of this syndrome: the ancestral reversion theory and the duplication theory. In this paper, similarities between a conjoined nail in conjoined twins and the palmar nail syndrome are described to support the duplication theory.     

Common nail disorders

The toenails and the rest of the human foot are constantly sandwiched in shoes, traumatized, and poorly supplied with blood that is necessary for normal morphology and function, resulting in more abnormal changes of the toenails (onychopathies). This article discusses briefly the following: (1) the conditions that are commonly seen in feet by podiatric practitioners; (2) clinical signs, symptoms, and etiology; and (3) differential diagnosis and care of the conditions.     

Microvascular nail transfer

A composite of nail and its skin appendages can be transferred for the foot to the hand by microvascular anastomosis. For technical reasons, the most suitable donor nail is from the big toe, and this most closely approximates the thumb nail. A finite portion of hemipulp must be included with the transfer to ensure adequate vascularization. Nail size can be reduced by resection of the edges of the germinal matrix so as to match the donor defects. For finger nail reconstruction, it is usually more practical to transfer the whole of the tip of the second or third toe to replace the whole of the tip of the finger. The indications of nail reconstruction by this technique are relatively rare and are predominantly cosmetic.     

Surgical nail procedures

As the so-called "non-surgical" nail procedures grow more and more aggressive and invasive in nature, the cold steel matrixectomy becomes an increasingly viable alternative. Many chemical and thermal matrixectomies are performed under poor aseptic conditions, increasing the risk of wound infection. With chemical matrixectomy, regulation of the level of tissue destruction is uncontrolled and often results in bone injury. The combination of these two elements can result in delayed diagnosis and recognition of osteomyelitis. When a practitioner is faced with a challenging ingrown, dystrophic, or mycotic nail, surgical nail removal should be considered the preferred technique. Etiologic variants of nail deformity, such as hypertrophied ungual labia, subungual exostosis, traumatized nail, and prominent underlying bony condyles, are well managed by the two procedure modifications presented. Advantages in asepsis, quicker wound healing, low reoccurrence rates, and good postoperative cosmesis make surgical nail removal a good choice. The difficulty of the technique and the danger of bone infection have frightened many practitioners away from the cold steel nail procedure. The preferred phenol technique or "p and a" may be simpler to perform, but it yields an unpredictable result. The constant draining and erythema of a phenolized nail may mask an underlying infection. This is one reason why cold steel nails are the preferred technique for nail removal in a diabetic patient. Complications makes cold steel a necessary addition to the surgeons armamentarium. We have presented a brief clarification and historical overview of the four most important contributors to surgical nail removal. These four techniques (Winograd, Frost, Zadik, and Kaplan) have been interwined into the two modifications commonly used today. By following the step-by-step surgical method presented and adding the reader's own successful techniques, a good surgical result can be easily achieved.     

Pediatric nail disorders

This article lists common pediatric nail disorders seen in infancy and adolescence. The diagnosis of pediatric nail disorders can be a sign of systemic disorders and diseases. The surgical treatment of young children and the treatment of pediatric patients are presented for those who do not frequently treat pediatric patients. The analysis of pediatric onychomycosis is presented, and the incidence and prevalence in the population is discussed.     

Advanced nail surgery

Six techniques not yet widely known or used in the dermatologic surgery of the nails are briefly described. Small-to-medium-sized tumours of the proximal nail fold (PNF) can be excised and the defect repaired with advancement or rotation flaps. A superficial biopsy technique of the matrix for the diagnosis of longitudinal brown streaks in the nail, which allows rapid histological diagnosis of the melanocyte focus to be performed, is described here. Because the excision is very shallow and leaves the morphogenetic connective tissue of the matrix intact, the defect heals without scarring. Laterally positioned nail tumours can be excised in the manner of a wide lateral longitudinal nail biopsy. The defect repair is performed with a bipedicled flap from the lateral aspect of the distal phalanx. Malignant tumours of the nail organ often require its complete ablation. These defects can be covered by a full-thickness skin graft, reversed dermal graft, or cross-finger flap. The surgical correction of a split nail is often difficult. The cicatricial tissue of the matrix and PNF have to be excised and the re-attachment of these wounds prevented. The matrix defect has to be excised and sutured or covered with a free matrix graft taken either from the neighbouring area or from the big toe nail.     

Heritable nail diseases

Heritable nail diseases are associated with a great variety of inherited diseases and syndromes. Well over 60 HEDs and numerous other inherited nail abnormalities are known to exist. A classification system of these disorders, as well as the specific nail change found in each, has been presented. Table 1 has been included to correlate many of the nail disorders with their corresponding inherited disease or syndrome. Clinically, inherited nail diseases may appear to be of questionable importance. In cases of primary presentation or poor historical background, however, these subtle nail changes may prove useful in arriving at or substantiating a diagnosis.     

The microvasculature of the nail bed, nail matrix, and nail fold of a normal human fingertip

The organization of the microvasculature of the dorsal human fingertip based on a vascular corrosion cast was examined using a stereoscopic microscope. The variations of the superficial capillary network of the 3 specialized areas of skin of the dorsal fingertip (the nail bed, the nail matrix, and the nail fold) are described. In the nail bed numerous capillary loops were observed arising from a deeper regular arrangement of sagittally aligned, parallel rows of vessels. The size and direction of inclination of the capillary loops varied, getting longer and more inclined to the nail bed distally, with the longest capillary loops seen at the hyponychium. There were no capillary loops at the nail matrix region, but there was a single, layered, rectangular plexus of capillaries in the plane of the nail matrix. This extended distally to sagittally stretched coils of vessels that straightened out as the nail matrix enters the nail bed region. At the edge of the proximal nail fold the capillary loops looked like fine bristles and were approximately 3 times shorter than those found on the nail bed and hyponychium. This study provides a baseline for future work in understanding the changes in the microvasculature of the dorsal fingertip due to injury or pathology.     

Distal replantation,nail bed,and nail problems in musicians

Nails enhance pulp sensibility, increase pulp stability and are necessary for fine prehension. A finger without a nail will compromise a musician's career if the finger involved is necessary to play a note (strings, keyboards) or hold a position (winds). Salvage of the nail is then a very important part of any surgical procedure in musicians with distal finger trauma. Surgical techniques will depend on the level and type of nail injury. Replantation is by far the best technique in distal finger amputation but, when not feasible, reposition-flap repair may be used. In isolated nail lesions, sutures, split-thickness nail bed graft, or nail matrix flaps are used according to the level and severity of the lesion.