The fingertip is the interface between humans and the world, including the various thorns, dirty needles, and other hazards to be found there. It is unsurprising that this is the site where hand infections most frequently occur. Although commonly encountered by hand surgeons and other physicians, fingertip infections have several mimics, and diagnosis and management is not always straightforward. Early diagnosis and treatment are key to success. As with all infections, they are more common and are more aggressive in immunosuppressed patients. This article reviews fingertip anatomy, common and uncommon fingertip infections and their mimics, and recommendations for management.

The nail unit is the most commonly affected area in hand infections, which can be primary infection or superinfection complicating other nail or skin disorders. Trauma, mechanical or chemical, is usually the trigger enabling infiltration of infectious organisms. Artificial nails and nail polish are also a possible cause of bacterial infection, harboring microorganisms. In severe acute bacterial infection, surgical intervention is often needed to prevent morbidity and disability. Abscess should always be drained, but viral infection such as herpetic whitlow, may mimic an abscess and, in contrast, requires non-operative treatment; to prevent sequelae. A more conservative approach is also generally advisable in less severe bacterial infection, other viral infections and in subacute or chronic nail infection. The present review deals with acute, subacute and chronic bacterial and viral infections of the nail unit, with a focus on diagnostic and treatment options. LEVEL OF EVIDENCE: III, systematic review of level III studies.

Also known as intravascular papillary endothelial hyperplasia, Masson\'s tumor is a relatively rare soft-tissue vascular tumor that usually arises in the hand. Felon is an abscess formation in the distal phalanx that usually occurs following a penetrating microtrauma. We present a 30-year-old patient who was referred to our clinic with a palpable mass in the distal phalanx of the index finger after a needle stick injury. At first, the lesion was treated as a felon but finally and after treatment failure, a complete reevaluation revealed the lesion to be a Masson\'s tumor of the distal phalanx.

Infections of the hand and forearm are a frequently seen surgical emergency of the hand. Patients of all age groups are affected and underlying systemic diseases are risk factors. Posttraumatic causes are the leading cause of infections. This includes cuts and stab wounds, animal and human bites but often also minor injuries. Due to the anatomical peculiarities of the hand, rapid progression of initially inconspicuous infections can occur resulting in functional limitations. If an infection is suspected, a symptom-oriented evaluation by a hand surgeon should be performed. This includes a detailed patient history, clinical examination, laboratory analyses and imaging. This is followed by the development of an individualized and interdisciplinary treatment concept with the aim of achieving the shortest possible rehabilitation period. The treatment includes surgical cleansing of the infection, accompanied by antibiotic treatment taking the expected possible spectrum of pathogens into account. Cephalosporins and aminopenicillins in combination with beta-lactamase inhibitors are the antibiotics of first choice. Follow-up treatment includes early functional exercise under the guidance of a hand therapist to minimize postinfectious restrictions in the range of motion and to enable occupational rehabilitation. In rare cases, fulminant necrotizing infections with resulting skin and soft tissue defects can occur. In these cases, secondary plastic reconstruction is usually required after cleansing of the infection.
UNASSIGNED: Infektionen der Hand und des Unterarms sind häufig gesehene handchirurgische Notfälle. Betroffen sind Patient*innen aller Altersgruppen, wobei systemische Grunderkrankungen als Risikofaktoren für die Entstehung zählen. Posttraumatische Ursachen stellen den führenden Grund für Infektion dar. Dies schließt Schnitt- und Stichwunden, Tier- und Menschenbiss-, aber häufig auch Bagatellverletzungen ein. Aufgrund anatomischer Besonderheiten der Hand kann es zu einer raschen Progression von zunächst unscheinbaren Infektionen kommen, mit daraus resultierenden funktionellen Einschränkungen. Bei Verdacht auf eine Infektion sollte eine symptomorientierte Abklärung durch einen handchirurgischen Facharzt erfolgen. Diese umfasst eine ausführliche Anamnese, klinische Untersuchung, Labordiagnostik und bildgebende Untersuchung. Anschließend erfolgt die Erarbeitung eines individualisierten und interdisziplinären Behandlungskonzepts mit dem Ziel einer möglichst kurzen Rehabilitationszeit. Die Therapie umfasst die chirurgische Infektsanierung, begleitend sollte eine antibiotische Therapie unter Beachtung des zu erwartenden Erregerspektrum eingeleitet werden. Cephalosporine und Aminopenicilline in Kombination mit β‑Lactamase-Hemmern stellen die Antibiotika der ersten Wahl dar. Die Nachbehandlung umfasst die frühfunktionelle Beübung unter handtherapeutischer Anleitung, um postinfektiöse Einschränkungen auf ein Minimum zu reduzieren und eine zeitnahe berufliche Rehabilitation zu ermöglichen. In seltenen Fällen werden fulminante nekrotisierende Infektionen mit daraus resultierenden Hautweichteildefekten beschrieben; hier bedarf es nach Sanierung des Infekts meist einer sekundären plastischen Rekonstruktion.

The hand is an extremely versatile organ adapted for fine tasks with various clinicoanatomical compartments. This article reviews the types of common hand infections that present to the emergency department and/or hand surgeon, with relevant investigations and strategies for diagnosis and treatment, with the emphasis on distinguishing between superficial and more serious infections.

The fingertip is the most common site of infections in the hand, which frequently are encountered by surgeons, dermatologists, and emergency and primary providers. Their mismanagement may have serious consequences. This review discusses the unique anatomy of the volar fingertip pulp and perionychium and reviews pathophysiology and treatment of acute and chronic paronychia, including the decision for surgical versus medical management, choice of antibiotics, incisional techniques, and postincisional care. Felons and the evidence regarding their management are reviewed. Several infectious, rheumatologic, and oncologic conditions that may mimic common fingertip infections and about which the managing provider must be aware are presented.

Mycobacterium abscessus is an environmental organism that has been implicated in pulmonary and extrapulmonary infections. Cases of furunculosis have been described in patients who underwent footbaths in nail salons; however, no cases of severe soft tissue infections or osteomyelitis have been reported following manicures. Here, we present the case of a 50-year-old woman who developed a felon in right index finger one week after having a manicure. She underwent incision and drainage of affected area. Cultures from purulence grew Mycobacterium abscessus. Imaging revealed osteomyelitis of distal phalanx. She was successfully treated with a prolonged course of antibiotics that included imipenem, linezolid, tigecycline, and clarithromycin. We highlight the importance of recognizing this uncommon complication and advocate the use of combined antibiotic regimens for an adequate treatment of this infection.

Infections of the hand are common entities that are frequently encountered by orthopaedic surgeons and primary care physicians.A high clinical suspicion and a thorough medical history with information about the social and working history of the patients, correct identification of the type and cause of the infection, and prompt initiation of appropriate treatment by the infectious diseases physicians and orthopaedic surgeons are required.Late diagnosis and inappropriate treatment may be a significant cause of morbidity for the hand and mortality for the patients. This article reviews the clinical spectrum and microbiology of the most common infections of the hand, and discusses the current concepts for their treatment. The aim is to increase the awareness of the treating physicians of the diagnosis and management of infections in the hand. Cite this article: EFORT Open Rev 2019;4:183-193. DOI: 10.1302/2058-5241.4.180082.

Infections are common in hand surgery and proper management is important to achieve optimal outcomes. Although most cases are not urgent, less common, severe infections such as flexor tenosynovitis and necrotizing fasciitis require urgent identification with both medical and surgical management. It is common for diagnoses to be missed or delayed because clinical and laboratory indicators are often variably present. Delayed identification and management can result in poor outcomes with permanent deficits. This article will provide a review of hand infections with a focus on identifying serious hand infections requiring urgent or emergent treatment, and distinguishing these from less urgent scenarios.

BACKGROUND: Cellulitis is a common clinical condition with low rates of morbidity and mortality if treated appropriately. Mimics of cellulitis presenting with erythema, edema, warmth, and pain can be associated with grave morbidity and mortality if misdiagnosed.
OBJECTIVE: This review investigates the signs and symptoms of cellulitis, mimics of cellulitis, and an approach to the management of both cellulitis and its mimics.
CONCLUSIONS: The current emergency medicine definition of cellulitis includes erythema, induration, warmth, and swelling. Given the common pathophysiologic pathways, cellulitis mimics often present in an analogous manner. These conditions include septic bursitis, septic joint, deep vein thrombosis, phlegmasia cerulea dolens, necrotizing fasciitis, flexor tenosynovitis, fight bite (closed fist injury), orbital cellulitis, toxic shock syndrome, erysipelas, abscess, felon, paronychia, and gouty arthritis. Many of these diseases have high morbidity and mortality if missed by the emergency physician. Differentiating these mimics from cellulitis can be difficult in the fast-paced emergency setting. A combination of history, physical examination, and focused diagnostic assessment may assist in correctly identifying the underlying etiology. For many of the high mortality cellulitis mimics, surgical intervention is necessary.
CONCLUSIONS: Cellulitis and its mimics present similarly due to the same physiologic responses to skin and soft tissue infections. A combination of history, physical examination, and diagnostic assessment will help the emergency physician differentiate cellulitis from mimics. Surgical intervention is frequently needed for high morbidity and mortality mimics.