Kristine Hoffman, DPM, FACFAS, and Jamie Mieras, DPM, FACFAS
Paronychias, subungual hematomas and nail bed lacerations are all toenail injuries that can bedevil runners after a race. These authors provide a practical guide to treating these injuries and their possible complications.
Running communities are full of stories of bloodied, lost toenails on marathon day, avulsed nails following rugged trail ultramarathons and runners performing nail avulsions on themselves to continue on multiday endurance events.
The literature supports the common occurrence of these injuries. In a review of post-marathon injuries, Mailler and Adams found dermatologic injuries to be the most common.1 The authors found blisters occurring in up to 39 percent of marathon runners, skin abrasions and chafing occurring in 0.4 to 16 percent of runners, and subungual hematoma occurring in 2.5 percent of marathon runners. In a study examining injury and illness rates in multiday ultramarathon runners, Krabak and colleagues found 95 percent of injuries to be minor in nature with 74.3 percent being dermatologic disorders, including subungual hematoma, nail avulsion and paronychia.2
The following are some of the common toenail injuries that runners sustain.
Key Insights On Acute Toenail Injuries In Runners
Toenail injuries in runners are common with both acute and chronic pathologies resulting from running-related injuries. Acute injuries can result from repetitive microtrauma, such as the nail plate repetitively contacting the end of the shoe during a long-distance running race, or due to single traumatic event such as a contusion from hitting a rock while trail running.
Acute nail injuries can cause significant pain and temporary limitation of activities. Long-term complications of these nail injuries include secondary fungal infections and nail plate deformities.
When Runners Sustain Subungual Hematomas
Repetitive trauma, as well as isolated blunt or sharp traumatic injury, to the nail plate can result in a collection of blood below the nail plate. These injuries can be extremely painful due to the pressure that develops below the nail. Pain can last for several hours to several days, depending on the extent of fluid accumulation and the integrity of the nail folds.3 Subungual hematomas are common running injuries and can result from many factors including poor shoe fit, steep and irregular terrain, and lower extremity edema.
Subungual hematoma presentation can vary from acute accumulation of hemorrhagic fluid below the nail plate to black discoloration of the nail plate secondary to dried subungual blood. Subungual hematoma is frequently accompanied by periungual ecchymosis, edema and erythema.4,5
Small, non-painful subungual hematomas that involve less than 25 percent of the nail do not require any treatment. In these small lesions, fluid will accumulate in the surrounding soft tissues and discoloration will gradually grow out to the free end of the nail plate. In painful lesions that involve more than 25 percent of the nail, authors have recommended trephination or avulsion with evacuation of the subungual hematoma.3 Numerous modalities for trephination exist and include handheld cautery, 18-gauge needle, nail drill, trephine, dental bur, heated paper clip, small rotary burr, #11 blade or carbon dioxide laser.
Nail plate avulsion is another modality for the evacuation and treatment of subungual hematoma. Avulsion allows for inspection and repair of concomitant nail bed lacerations. Recommendations vary as to the extent of nail plate involvement that warrants nail avulsion over trephination.
Malay recommends trephination for structurally stable nail folds and involvement of less than 25 percent of the nail pate.3 Simon and Wolgin report that there was a 60 percent incidence of nail bed laceration requiring nail plate avulsion and repair in subungual hematomas involving more than 50 percent of the nail.6 Additionally, the authors reported a 94 percent incidence of nail bed laceration requiring nail plate avulsion and repair, regardless of hematoma size, when distal phalangeal fracture was present. Van Beek and coworkers recommend avulsion in cases involving 25 to 50 percent of the nail plate due to a 50 percent incidence of associated nail bed laceration.7 A more recent study has shown that trephination is a viable treatment option regardless of hematoma size or the presence of a distal phalanx fracture.8
Possible complications resulting from subungual hematoma include nail plate deformity and secondary infection. Traumatic injury to the germinal nail matrix can result in permanent nail deformity. Both significant force and a large fluid accumulation can result in separation of the nail plate from the nail bed, resulting in traumatic onycholysis. Separation of the seal of the nail cuticle exposes the nail bed to both bacterial and fungus, potentially leading to secondary infection.
What You Should Know About Nail Bed Lacerations
Significant sharp or blunt trauma to the digit can result in laceration of the nail bed. While nail bed laceration is less common in road and track running, the increasing popularity of trail running, in which athletes often encounter unstable rocky terrain, has led to increasing numbers of these injuries. Nail bed lacerations are present in 60 percent of hematomas involving 50 percent or more of the nail and in 94 percent of distal phalanx fractures.6,7
The recommended treatment for nail bed laceration involves nail plate avulsion, irrigation, debridement and primary repair.3,9 Following a local anesthetic digital block, avulse the affected nail plate. Then prepare the digit with iodine or another antiseptic solution, apply sterile draping, exsanguinate the digit, and apply a digital tourniquet. Irrigate the nail bed and remove debris and the remaining hematoma. Take care to avoid aggressive debridement as the nail bed tissue is friable and easily disrupted, which can lead to scar tissue formation.
Repair nail bed lacerations using 4-0 to 5-0 absorbable suture on a tapered needle. Soft tissue adhesives, such as Dermabond (Ethicon), are an alternative to suture closure.10 Insert either the nail plate or non-adherent gauze between the proximal nail bed and proximal nail fold to preserve the proximal nail groove.3,9 Then apply standard sterile dressings.
Possible complications of nail bed lacerations include hypertrophic scar formation that inhibits proper adhesion of the nail plate to the nail bed, damage to the germinal matrix resulting in absent or irregular nail growth, and infection.3 Nail plate laceration with a digital fracture constitutes an open fracture and necessitates appropriate antibiotic management. Fox reports a case of osteomyelitis following an open nail bed injury and recommends irrigation, debridement and parental antibiotics in these injuries to decrease the risk of secondary osteomyelitis.11
Pertinent Pointers On Treating Acute Paronychia
Paronychia is an inflammatory condition of the epidermis bordering the nail. Paronychia most commonly results from infection but may also have a non-infectious etiology, such as ingrown nail, contact irritants, foreign bodies and prolonged exposure to moisture. Paronychia is a common injury in runners due to tight fitting shoe gear, trauma and prolonged exposure to moist environments within running shoes. Acute paronychia typically presents with redness, swelling, pain and possible fluctuance or purulent drainage from the paronychium. The most common infecting organisms are Staphylococcus aureus, followed by streptococci and Pseudomonas.12
Several treatment modalities for paronychia exist and the treatment choice depends on severity of the disorder. Warm water soaks three to four times per day, topical antibiotics and topical antibiotics in combination with topical corticosteroids are reportedly effective treatments for mild paronychia.12,13 More severe paronychia and treatment-resistant lesions frequently require oral antibiotic therapy. If drainage is present, obtain cultures prior to initiating antibiotic therapy. Clinicians frequently use the anti-staphylococcal agents clindamycin and cephalexin for the initial empirical antibiotics. When runners have paronychias, in which water and dirt contamination is frequent, consider broad-spectrum oral antibiotics such as amoxicillin/clavulanate, clindamycin and trimethoprim/sulfamethoxazole.14
Surgical treatment of paronychia is recommended for severe lesions and when an abscess is present. Surgical management begins with a local anesthetic block of the digit and preparation with topical antiseptic. Remove a 2 to 3 mm linear portion of the nail margin. This relieves the pressure of the adjacent edematous nail fold and allows sustained drainage.15 In runners, due to the potential side effects of systemic antibiotics as well as the desire for rapid return to activity, surgical treatment is frequently the optimal treatment modality.
Several complications reportedly result from paronychias, largely from progressive infection or chronic inflammation. Subungual abscess with elevation and disruption of the nail plate is reportedly a complication in cases of severe paronychia.13 In rare cases, paronychia can progress to osteomyelitis of the underlying distal phalanx.16 Abdul and colleagues report a case of Marjolin’s squamous cell carcinoma occurring in a toe with a history of multiple ingrown toenails and secondary osteomyelitis.17 These cases highlight the need to maintain a high index of suspicion and consider magnetic resonance imaging and/or biopsy of irregular lesions and ulcerations in the setting of chronic paronychia.
Treatment Pearls For Pyogenic Granuloma
Pyogenic granulomas are relatively common benign vascular skin growths. Several factors contribute to the formation of pyogenic granulomas including repetitive irritation, trauma and hormonal factors. In the foot, repetitive trauma to an ingrown nail may also result in the formation of a pyogenic granuloma.
Repetitive shoe gear irritation as well as trauma to an adjacent ingrown nail can lead to the formation of these lesions in runners. These vascular lesions are characterized by red, easily bleeding tissue with a thin layer of overlying epithelium. Several benign and malignant skin tumors have an appearance similar to pyogenic granuloma, making biopsy and histological diagnosis very important, especially when a lesion is atypical.
Treatment options for pyogenic granuloma include sharp excision with desiccation of the base with phenol or silver nitrate.18,19
When Digital Mucoid Cysts Arise In Runners
Other benign tumors that can occur around the toenails of athletes include digital mucoid cysts. Digital mucoid cysts are benign nodular lesions that contain clear gel and theoretically originate from mucoid degeneration. Commonly, these lesions communicate with the interphalangeal joint, which often exhibits degenerative changes.
The high impact nature of running increases the risk of degenerative changes to the interphalangeal joints as well as formation of these lesions. While many are asymptomatic, trauma to lesions can cause pain and the lesions themselves can cause adjacent nail deformity. In runners, these lesions are more likely to be symptomatic due to shoe gear irritation.
Karte and coworkers describe a case involving a soccer player’s mucoid cyst, which resulted in a painful convex deformity of the athlete’s nail.20 While little research has focused on these lesions, authors suspect that their anatomical location on the digits and adjacent toenail would make these lesions susceptible to trauma and irritation in runners. Treatment options for digital mucoid cysts include aspiration, local corticosteroid injection and surgical excision.
How To Treat Chronic Toenail Injuries In Runners
Both acute and chronic toenail injuries are common pathologies among athletes. While the symptoms of acute injuries, such as subungual hematoma and paronychia, often lead patients to seek prompt treatment, chronic nail injuries can go untreated for years.
The most common chronic toenail injuries in athletes are traumatic onychodystrophy and onychomycosis. Chronic nail changes can occur with microtrauma from tight shoes as well as biomechanical and structural abnormalities that place pressure on nail areas. Repetitive trauma to the nail borders, nail plate or nail matrix can lead to onychodystrophy, which can be characterized by repeated nail loss, thickening of the nail plate, or nail plate deformity. Secondary fungal nail infection can also result from nail trauma, allowing fungal hyphae entrance to the nail bed. Environmental factors such as shared wet areas and occlusive, sweaty footwear further increase the risk of fungal nail infection in runners.
Expert Insights On Onychodystrophy In Runners
The repetitive nature of running predisposes athletes to traumatic onychodystrophy. Persistent microtrauma to the nail apparatus can lead to several chronic pathologic changes of the nail bed. These changes include:
• subungual orthokeratotic keratinization (formation of an anulcear keratin layer below the nail plate);
• lichen simplex chronicus of the nail unit (or thickening of the skin of the nail unit with variable scaling that results secondary to repetitive scratching or rubbing);
• onychauxis (pathologic keratinization of nail bed/thickening of nail complex);
• onycholysis (pathologic detachment of the nail plate from the nail bed):
• onychoclavus (hyperkeratosis under the distal nail margin);
• onychophosis (local or diffuse hyperkeratosis to the nail folds resulting from repetitive microtrauma); and/or
• onychogryphosis (enlargement and thickening of the nail plate).21-24
Treatment as well as prevention of these onychodystrophic nail changes should include shoe gear modification, including changes to longer and/or wider shoes. Many running shoe manufacturers make running shoes with wide toe boxes or incorporate flexible uppers to decrease pressure to the digits and nail apparatus. Brands including Altra and Topo have a wide toe box that can accommodate structural deformities and help to protect the nail plates.
Other treatment modalities for onychodystrophy include manual nail plate debridement and chemical nail plate debridement (47% urea nail gel).21,25 Researchers have shown that applying topical glucocorticoids to the proximal nail fold is a successful treatment for lichen simplex chronicus of the nail unit.26 Topical keratolytics, including 40% urea, lactic acid 12% and salicylic acid 6 to 20%, are reportedly effective treatments for hyperkeratosis of the nail folds.27 Surgical or chemical matrixectomies are treatment options for nail changes that fail to respond to more conservative treatment modalities or cause significant dysfunction.28
Addressing Onychomycosis In Runners
Runners encounter numerous risk factors for the development of fungal nail infections. These risk factors include heavy perspiration, moist environments, going barefoot in public places such as gyms and swimming pools, tinea pedis infection, minor skin and nail injury, and traumatic damage to the nail. Both traumatic nail injuries and traumatic onychodystrophy can serve as precursors to the development of onychomycosis.
Given the similar appearance of onychomycosis and traumatic onychodystrophy, authors recommend nail biopsy with KOH preparation, periodic acid Schiff (PAS) staining or fungal culture for accurate diagnosis and appropriate treatment.29 Treating onychomycosis in runners should include preventative foot care with instructions for patients to wear shower shoes in shared areas, changing footwear after activities and regular nail care to prevent trauma.
The majority of fungal nail infections are due to the dermatophytes Trichophyton rubrum, Trichophyton mentagrophytes and Epidermophyton floccosum. The gold standard treatment for onychomycosis is systemic antifungal medication. This includes the oral medications terbinafine (Lamisil, Novartis), itraconazole (Sporanox, Bristol-Myers Squibb), fluconazole and griseofulvin.30 Frequently, runners choose to avoid oral medication due to concern that it may negatively affect their performance.
Historically, topical ciclopirox nail lacquer was the only prescription topical medication available for the treatment of onychomycosis. Success of this medication for the treatment of onychomycosis was very limited with less than a 9% complete clearance rate.31
Recently, efinaconazole 10% solution (Jublia, Valeant Pharmaceuticals) and tavaborole 5% solution (Kerydin, PharmaDerm) have been introduced as new topical treatment options for the treatment of onychomycosis. Researchers have shown that the efficacy of efinaconazole and tavaborole solutions is comparable to oral itraconazole, and more than three times as effective as ciclopirox.32,33 These newer topical treatment options are frequently attractive treatment modalities for athletes who wish to avoid systemic medication.
Acute and chronic toenail injuries are common among runners. These injuries have the potential to limit participation in sport and can lead to permanent nail deformities. Prompt diagnosis and management can lead to improved outcomes with the prevention of complications and a more rapid return to sport.