Jared K. Wilson and Dr. Kenneth L. Knight, Exercise Sciences
Paraffin wax baths are used by athletic trainers and physical therapists to apply superficial heat to the extremities of patients. The National Athletic Trainers Association (NATA) includes the use of paraffin wax as a required competency for students who are working toward certification. While the general consensus of many athletic trainers and textbooks1,2,3 is that paraffin wax application is an effective superficial heating modality, data is not available to back up such opinions. Not enough research has been done to quantify its heating effects or to compare it to other superficial heating modalities.
Very few studies have looked at the use of paraffin wax as a therapeutic modality, and those that have are vague and imprecise.4,5 For example, Borrell et al4 mentioned the importance of the size of an area treated with thermal modalities, but failed to state how much area they treated during their experiments. Abramson et al5 also attempted to quantify temperature changes resulting from paraffin wax application; however, they treated a larger area (the hand and forearm up to the elbow) than a normal clinical application (the majority of paraffin heating units are just big enough to accommodate a hand, wrist, foot, or an isolated elbow).1,3 Since tissue heating is a function of the area to be treated, Abramson et al’s results may differ from normal clinical application.4,6 Abramson et al were the only researchers found to compare paraffin wax with moist heat packs.
The lack of accurate studies has only led to speculative comparisons of paraffin’s effectiveness against that of other superficial heating modalities (i.e. moist heat packs) that are commonly available in most athletic training and physical therapy facilities. Authors commonly group paraffin wax and moist heat packs as superficial heating modalities, only distinguishing the two by referring to the usefulness of paraffin wax in treating distal extremities.1,3 In addition, some claim that paraffin wax provides more heat to the treated area than water-based modalities.2,6 At the same time, there are anecdotal references from clinicians supporting the use of moist heat packs to warm the hand. Appropriate studies of the temperature changes induced by paraffin wax and comparisons with other therapeutic agents such as moist heat packs are needed to validate alternatives for treating patients with superficial heat modalities. Our objective was to meet this need by measuring surface and intramuscular temperature changes of the hand prior to, during, and following an application of dip-wrap paraffin wax and a moist heat pack.
To complete my study, I recruited 36 students from various courses at BYU. Each subject was scheduled for 3 visits to the modalities lab. During each visit I placed 2 surface thermocouples on the left hand of the subject: one on the thenar eminence and another in the web space between the index and middle finger. An intramuscular thermocouple was inserted 1 cm deep into the muscle belly of the thenar eminence. Following thermocouple placement the subject was given 5 minutes to achieve a baseline temperature, after which a treatment (paraffin wax, moist heat pack, or control) was applied for 20 minutes. Temperatures were monitored for approximately 13 minutes following the treatment.
One of the arguments that people have in favor of paraffin wax is that it conforms to the contours of the hand and fingers, supposedly delivering more heat between the fingers than a moist heat pack could provide. However, by placing a thermocouple in the web space between the fingers I was able to measure the temperature of that location and found the moist heat pack applications reaching slightly higher temperatures than the paraffin wax applications (37.41 ± 2.2°C and 37.24 ± 1.4°C, respectively). Intramuscular temperatures during moist heat pack applications were substantially greater than paraffin wax applications (37.40 ± 1.5°C and 36.23 ± 1.2°C, respectively) as were thenar surface temperatures (41.56 ± 1.6°C and 37.62 ± 2.1°C, respectively). After analyzing the results of the study, it is my conclusion that a moist heat pack application will heat the hand just as well as—and possibly better than—a paraffin wax application.
For the sake of practicality, there is no dispute about the convenience of using a hot pack rather than paraffin wax. The wax is messy, can stain clothing, and is difficult to clean up. Heat packs are just the opposite and do not leave an oily residue on the skin; they can be especially useful for athletes who need good grip in whatever sport they may be involved with. Some of the subjects mentioned discomfort with the amount of heat during the moist heat pack application while others had no problem; unfortunately due to replication issues, we could not adjust our heat pack application to the comfort of each subject—in an actual therapy setting this is an issue that can easily be dealt with on a case by case basis by the clinician.
Despite its cumbersome nature, there is something to be said of paraffin wax’s non-heating properties: after a treatment the hands are left soft (probably because of the mineral oil)—a fact that should be respected especially if the patient is to receive a post-application massage. However, taking evidence from the data into consideration along with ease of use, for most situations I would recommend using moist heat packs to heat the hand. My findings will be reported to a regional or national professional conference, and a manuscript will be submitted to a peer-reviewed medical journal.
Sources
- Prentice, WE: Therapeutic Modalities: For Sports Medicine and Athletic Training, ed 5.
McGraw Hill, Boston, 2003, pp 79–80. - Starkey, C: Therapeutic Modalities, ed 3. FA Davis Co, Philadelphia, 2004, pp 142–143.
- Denegar, CR: Therapeutic Modalities for Athletic Injuries. Human Kinetics, Champaign, 2000,
p 114. - Borrell, RM et al: Comparison of In Vivo Temperatures Produced by Hydrotherapy, Paraffin Wax Treatment, and Fluidotherapy. Physical Therapy, 1980, 60:1273–1276.
- Abramson, DL et al: Effects of paraffin baths and hot fomentations on local tissue temperature. Arch Phys Med Rehabil, 1964, 45:87–94.
- Michlovitz, SL: Thermal Agents in Rehabilitation, ed 3. FA Davis, Philadelphia, 1996, pp 116–121.