This study is being done to test if paraffin wax can be used to improve the range of motion and function for scars across joints when used in combination with scar rehabilitation therapy sessions. For those randomized to receive it, the paraffin wax will be used alongside the participants' exercise therapy treatments. Currently, treatments that are used in addition to rehabilitation therapy for increasing range of motion across joints in the burn population are limited. By getting more information about how paraffin wax may or may not work, patients in the future that have scars may be able to be helped.

If the participants agree to take part in this study, the participants scars will be looked at and the investigators will select one site that will be involved in the research. The scar will be "randomized" to the paraffin wax or no paraffin wax groups. The treatment the participants get will be chosen by chance, like flipping a coin. Neither the participants nor the study doctor will choose what treatment you get. The participants will have a 50% chance of being given either paraffin wax or not.

The study will take place in an outpatient setting. The participants will not be admitted to the hospital overnight. All patients who enter the study will be required to follow-up for regular appointments with their burn department.

Before the participants begin treatment, the participants will come in for a pre-treatment visit where the investigators will collection information about the participants scars such as pictures, range of motion measurements, non-invasive probes, non-invasive imaging (Laser doppler imaging) and questionnaires. These questionnaires will be related to the symptoms, range of motion, function, and appearance of the participants' burn scars. At the pre-treatment visit, there is an also an optional blood draw where less than 2 tablespoons of blood are collected. It is estimated this visit will take less than 1 hour. The investigators will also collect information from the medical record about prior surgical and medical history.

Exercise treatments (which the participants have previously chosen to undergo in talking with the participants doctor) will occur approximately in 1-2-week intervals depending on what the Burn Center scheduling department allows. For completion of this study, the participants will undergo 4 exercise therapy sessions which may take about 8 weeks.

At each visit, the following measurements will be captured before and after each exercise session. Those assigned to the paraffin wax group will have an additional assessment collected before their exercise therapy session and after the paraffin wax has been removed. Measurements at each visit include active and passive range of motion measurements of the affected joint, non-invasive probe measurements to measure water loss and hardness of your scar and the adjacent area of normal skin, digital photography, non-invasive laser doppler imaging (LDI), surface-level skin temperature measurements using either an infrared thermometer or skin temperature strip as well as pain and itch rating scales.

When applicable, the paraffin wax will be applied to the top of the scar for 15 minutes and repeat measurements previously listed above will be collected before your standard of care rehabilitation session. These sessions conducted by the burn rehab therapist may include scar massage, exercises, and functional activity. Specific treatments will be documented.

At each study visit, photographs will be taken of the study designated scar. All photographs taken for the purpose of this study will be taken by a high-resolution study camera. Photographs will be labeled with your study ID number. All efforts will be made to minimize the amount of identifiable information such as the participants' face or tattoos in these photos.

The procedures/treatments in this study that are considered experimental/investigation are: the use of the study product (paraffin wax) to assess the effect on burn scar that crosses an extremity joint during rehabilitation exercises.

The following procedures are part of the research study and would not normally be done as part of routine care: study provided paraffin wax and control application to the scar, scar assessments, digital photography, LDI, non-invasive imaging and measurements. These procedures are part of the study and will not be charged to insurance.

Inclusion Criteria:

• Age ≥ 18 years
• Patients with burn scar that crosses an upper or lower extremity joint (shoulder, elbow, wrist, hand, hip, knee, ankle)
• Patients that have been prescribed a rehabilitation program where paraffin wax could be used as an adjunct to rehab exercise therapy

Exclusion Criteria:

• Adults unable to provide informed consent
• Injury etiology other than burn (ex: cutaneous trauma, cold injury, etc.)
• Pregnant women
• Prisoners