Candidates for foot care certification preparing for examination must be educated on safe and effective nail debridement. Foot problems will occur in at least 75% of Americans; toenail disorders are the most common foot problem in the elderly due to a constellation of issues including impaired vision, inability to reach their feet, thinning of the epidermis/dermis, vascular-related trophic and edema conditions, and deformed hardened toenails.1 When disease processes occur in the toenail, the function of the nail plate to protect the soft tissue to the distal end of the phalanges may be compromised. Appropriate nail debridement assists in the maintenance of this critical function.

Knowledge of nail anatomy is important to any safe debridement procedure including the ability to identify the free nail border. Routine nail anatomy includes the appearance of a healthy nail plate. A healthy nail plate, which is translucent, appears in hues of pink with proper vascularization. The nail matrix originates in the nail root, a tapered anatomic structure extending 7 to 8 mm further beneath the eponychium's seal between the nail and the digit. The lunula is the term for the moon-shaped distal aspect of the matrix that will have a different color or tone from the remaining distal aspect of the nail plate. Soft tissue surrounding the nail plate is known as the paronychium, and is the origin of the disease process paronychia, where a painful pustule can occur.

Commonly encountered altered anatomical and disease states, known as onychopathology, include onychomycosis, onychocryptosis, paronychia, and onychogryphosis. Onychomycosis is a fungal infection of the nail. Infection is typically caused by dermatophytes, as opposed to candida, and thus can also be referred to as tinea unguium.2 Mycotic nails may present with yellow, tan, or brown discoloration. The nail plate may be thickened, brittle, and easily break off into small pieces. Medical terminology for an ingrown toenail is onychocryptosis, the “crypt” being the small pit or recess where the nail plate has extended beyond normal anatomical position. Onychogryphosis presents as large, deformed, hypertrophic nails.3 The etymology of the Latin “gryph” is short for gryphon denoting nail plates appearance as that of a griffin, as a talon or claw. Nails displaying onychogryphosis are sometimes known as “rams horn” nails due to the proclivity of untrimmed, thickened nail plates to curl like the horn of a ram. The loss of normal nail translucency during these disease states can increase difficulty in identification of the free nail border, increasing the risk of soft tissue damage from the unskilled or inattentive foot care specialist during debridement.

Nail debridement is used to trim nails when the nail is abnormal in thickness or appearance. Selection of appropriate nail care debridement tools and equipment may include tissue nippers, rasps, irises, mechanical rotary tools, ingrown nail shavers, curettes, and scalpels. Personal protective equipment needed depends upon tools selected. In addition to universal precautions, the consideration of potential loose nail fragments, body fluids, and fine skin or nail particulates guides the selection of personal protective equipment, which may include eye protection and masking. Tool selection is based on multiple factors including clinician preference, sterilization ability, cost, and patient presentation.

The nail debridement procedure includes avoidance of potential soft tissue injury and promotion of ingrown toenails by trimming the nail straight across and no more than 1/16″ to 1/8″ from the end of the toe.1 After trimming, the nail should be smoothed as needed with a file. Hyperkeratosis, also known as keratoma or callus tissue, should also be removed and addressed in the treatment plan. When using sharp instruments, several principles are crucial in the clinician's procedural plan. This includes a method to anchor oneself to the patient. A point of contact between the clinician and the patient must be maintained to prevent injury to either party in the event of movement. The digit undergoing debridement may also need to be secured to prevent movement during the procedure. As tissues vary in their depth and ease of debridement, another key consideration is to aim sharp instruments away from the clinician. Always cutting away from oneself prevents the sudden encounter of soft tissue beneath a callus leading to injury. The adage “start low and go slow” is commonly taught to acknowledge the premise that more tissue can be removed, but once tissue is debrided, it cannot be replaced.

Instrument disinfection is an important final component in the delivery of nail care to ensure the safety of future patients who will receive care utilizing the equipment. Sterilization guidelines should be followed and may include disinfectant solutions, cold sterilization, and autoclaves.

The Certified Foot Care Nurse (CFCN) must be aware of the role nail debridement plays in optimal foot care management as well as interventions that can treat or prevent complications seen from nail debridement. Candidates preparing for WOCNCB foot care certification should also be aware of patient considerations that would preclude the performance of nail debridement and what assessment findings might spur referral for safe patient management.

Question 1

1. A patient with a medical history including type 2 diabetes presents for routine nail debridement with a tunneling foot wound having exposed bone beneath the nail plate. The CWOCN-AP suspects osteomyelitis. What rationale would drive the safe use of negative pressure wound therapy (NPWT) in this situation?

NPWT is contraindicated when there is exposed bone or tunneling. NPWT is contraindicated for chronic wounds. NPWT is contraindicated when there is untreated osteomyelitis. NPWT is contraindicated for patients with diabetes mellitus. ANSWER: C

Rationale: NPWT is contraindicated when there is untreated osteomyelitis but can be used after treatment has begun. NPWT is efficacious and safe for treatment of acute or chronic wounds, wounds with exposed bone or tunneling, and in patients who have diabetes mellitus.

Domain 2 Task 3: 020307

Question 2

2. The CWCN assesses the patient during routine foot care and notes new-onset green and black discoloration of the hallux nail plate with malodor. The nail plates on the remaining digits are intact. The foot is warm, and the capillary refill is less than 3 seconds. What is likely the cause of a nail plate green or black nail discoloration with malodor?

Fungal nail disease Bacterial nail disease Ischemic tissue with peripheral vascular disease Onychocryptosis ANSWER: B

Rationale: Bacterial infection such as Pseudomonas aeruginosa can present as black or green nail discoloration with malodor. Answer A is incorrect as a fungal infection enters the distal or lateral nail margin, invading the nail bed causing discoloration and dystrophy. The nail plate may then become thin and brittle or thick and lytic. Answer C is incorrect as green discoloration is less likely, and the foot has a reassuring vascular examination. Onychocryptosis is the onychopathology of an ingrown toenail.

Domain 2 Task 4: 020402

Question 3: Certified Foot Care Nurse (CFCN)

3. A 72-year-old patient is receiving skilled nursing care in the home for the management of diabetes. The home care nurse is aware that an ankle-brachial index (ABI) has been ordered to be performed prior to nail debridement for this patient. Which statement indicates the patient requires more education?

“I will be referred for further testing and evaluation if the ABI is less than 1.0.” “I will avoid stimulants or heavy exercise for an hour prior to the test.” “I will be placed in a flat, supine position.” “The cuff will inflate the 20 to 30 mmHg above the point where the pulse is no longer audible.” ANSWER: A

Rationale: Referral for further testing and evaluation occurs if the ABI is less than 0.90 or greater than 1.30. Patients should be placed in a comfortable position and should avoid stimulants, as these can create false results. Inflation of the cuff should be 20 to 30 mmHg where the pulse can no longer be heard.

Content outline: Domain 2 Task 4: 020202

Question 4: Certified Foot Care Nurse (CFCN)

4. A point of contact between the clinician and the patient must be maintained during nail debridement to:

Prevent injury to either party in the event of movement. Allow the clinician to continuously assess the patient. Provide the proper angle to prevent injury. All of the above. ANSWER: D

Rationale: Anchoring oneself to the patient when using sharp instruments is safe practice to prevent injury to both the patient and the nurse allowing the clinician to continually assess the patient's extremity movements and allow for the correct angle to prevent injury.

Domain 2 Task 4: 020405

REFERENCES 1. Lipsky BA, Berendt AR, Cornia PB, et al. 2012 Infectious Diseases Society of American Clinical Practice Guideline for the Diagnosis and Treatment of Diabetic Foot Infections. Clin Infect Dis. 2012;54(12):e132–e173. 2. Woody J. Overview of diabetic foot care for the nurse practitioner. J Nurse Pract. 2020;16(1) 28–33. doi:10/1016/j.nurpura.2019.08.11.