This is a question that is being asked by healthcare professionals in the hospital setting, by those in clinics (medical and physical and occupational therapy), and by individuals, primarily diabetics, looking to purchase monofilaments for home use
Monofilament testing is an inexpensive, non-invasive, easy-to-use, portable, and first line-of-detection test for assessing the loss of protective sensation in individuals with Peripheral Neuropathy. Peripheral Neuropathy is a condition that results of damage to peripheral nerves and is characterized by symptoms of pain, numbness, tingling and weakness, and a loss of ability to detect pressures or lesions of the feet and hands.
A monofilament is a single-fiber nylon strand that is designed to bend at a certain perpendicular force of application and is used to test for loss of protective sensation in individuals with peripheral neuropathy. In this condition, the individual may be unable to detect even the smallest of lesion or compromise to the skin and can lead to an increased risk of developing an infection and ulceration of the foot, and the potential for lower extremity amputation.
Because the test requires that these monofilaments are pressed against the skin on the plantar surface of the bare foot, they may be exposed to pathogens and lead to contamination of the monofilament thread. The growing prevalence of resistant organisms like methicillin-resistant Staphylococcus aureus (MRSA) has caused medical facilities/hospitals to implement preventive measures against the spread of this organism. For the diabetic patient, this is of particular interest and concern because an infected foot ulcer is one of the most common reasons for hospital admission. While there is still more to learn about the mechanism(s) that these pathogens are spread between patients, the diabetic is at risk for infection.
Ensuring that the monofilament is clean of bacterial load with each new test is essential. Further, the monofilament thread must have maintained the strength of its original calibration so that the buckle point reflects that correct force, for example at 10 grams of force, when used. Both of these are important elements of test safety and efficacy that must be considered when evaluating the pros and cons of the multi-use verses single-use monofilament products.
The Pros & Cons of Single Use Monofilaments
- No risk of the spread of pathogens if protocols are adhered to with the monofilament being discarded after each use, thus never contacting another patient’s skin
- No need to clean the monofilament thread which reduces the time required for use
- The calibrated force in grams of applied linear force before buckle should be accurate as the monofilament has not been repeatedly used which could lead to mechanical weakening overtime and a loss of initial calibration strength
- The cost of the consumable product may be more expensive if multiple monofilament tests are performed in a given facility, as compared to the one-time cost of a multi-use monofilament device
- A single use monofilament test consists of the monofilament thread attached to a rectangular paper component that may not present the same professional appearance as the uniquely designed medical looking multi-use devices
For more information see The Pros & Cons of Single Use Monofilaments
The Pros & Cons of Multi Use Monofilaments
- A single purchase can last for a significant length of time before requiring purchase of a new product and may represent cost savings
- Professional look portrays professionalism whereas a single-use product may not
- After each use, the monofilament must be wiped clean using an alcohol wipe to reduce the bacterial load, and then properly stored according to manufacturer’s guidelines. This takes additional time as compared to simply discarding the device after use
- The initial up-front cost is significantly more expensive than the single-use product
- The calibration of linear force at which thread buckle occurs may weaken overtime and this may not be detectable by the user. Further, literature suggests that these multi use reusable monofilaments not be used on more than 10 patients without a 24-hour rest before using again
Note: Regardless of the monofilament used, they should not be used on areas of the foot with ulcers or open sores of any kind. Its use is intended for places where the skin is intact.
For more information see The Pros & Cons of Multi Use Monofilaments
From the aforementioned pros and cons you can see that the best choice of which monofilament to use will certainly be affected by the setting in which the monofilament is used – busy hospital or clinic conducting several tests each day, a setting where monofilament tests are only conducted sporadically and, in few numbers, at home use, etc. – and the individual preference of the persons conducting the testing.
Lynn Perkes is a full-time faculty member at Brigham Young University-Idaho teaching courses in Kinesiology and Biomechanics, Applied Kinesiology and Assessment, Therapeutic Exercise, and other Physical Therapist Assistant classes. He writes part-time for ProHealthcareProducts.com, who sells healthcare, medical, therapy, fitness, and personal protective equipment and supplies.