Iontophoresis With Dexamethasone and Physical Therapy to Treat Apophysitis of the Knee in Pediatrics

The goal of this clinical research study is to determine if there is a difference in time to meet return to sport criteria for Pediatric patients with apophysitis of the knee who receive iontophoresis with Dexamethasone Sodium Phosphate (DSP) and Physical Therapy (PT) as those who receive iontophoresis with placebo and PT or PT alone.

Approximately 147 patients will be enrolled in this study.

Iontophoresis is a treatment that allows medication to be delivered across your skin to the painful area without having to have an injection into your muscle or soft tissue, through a vein in your arm, or taking a pill. Instead, liquid medication is placed on a patch (like a large Band-Aid) and then placed on your knee over the location where it hurts. A plastic device, like a battery, is then attached to the patch for three minutes. During this time, this device begins to deliver the medication through your skin and into the area that hurts, and also charges the patch so it can continue to deliver the medication for two hours once the device is removed. The medication is delivered by a mild electrical current. The most common drug used with iontophoresis for pain caused by such things as apophysitis of the knee is dexamethasone sodium phosphate (dexamethasone).

This is an investigational study. Dexamethasone is a steroid medication that has been approved by the U.S Food and Drug Administration (FDA) to treat many types of problems (such as joint problems, skin and allergy problems, eye, stomach, and lung problems), but has not been approved to treat apophysitis of the knee using iontophoresis. In this study, it is an experimental drug.

Participants will be randomized to one of three treatment groups:

* Physical therapy with iontophoresis using Dexamethasone
* Physical therapy with iontophoresis using an inactive drug called a placebo
* Physical therapy alone

Participants will be asked to attend study visits twice/week for up to 8 weeks or until they are able to pass the Return To Sport Checklist, whichever is sooner. Participants will the receive a 30-Day Follow Up phone call and complete a survey at the 90-Day mark, making each participant's study duration approximately five (5) months.

Eligibility Criteria:
Inclusion Criteria:

1. Written approval from the referring physician for potential subject to be considered for enrollment into this study
2. Provision of signed and dated informed consent form
3. Stated willingness to comply with all study procedures and availability for the duration of the study
4. In good general health as evidenced by written approval from referring physician for potential inclusion in study.
5. Has the ability to effectively identify pain/burns and communicate with the investigators or their parents that they are experiencing pain or burning during treatment
6. Referred to CHKD Sports Medicine PT by CHKD Primary Care Sports Medicine physicians or CHKD Orthopedics physicians with a diagnosis of apophysitis of the knee and with a prescription for standard PT treatment with iontophoresis
7. Able and willing to complete iontophoresis treatments within eight (8) weeks of first treatment
8. Must be ambulatory
9. Males 7 to 14 years of age who have not reached skeletal maturity (skeletal maturity based on referring physician's clinical judgement or as demonstrated via radiograph images taken within 90 days of enrollment)
10. Females 7 to 14 years of age who have not reached skeletal maturity (skeletal maturity based on referring physician's clinical judgement or as demonstrated via radiograph images taken within 90 days of enrollment) and who meet one of the following criteria:

    1. Pre-menarcheal
    2. Within two (2) year post onset of menses
11. Males or females over the age of 14 only with radiographic evidence of skeletal immaturity, with images taken within 90 days of enrollment
12. Index knee symptomatic for pain with activities of daily living or while playing sports.

Exclusion Criteria:

1. Index knee symptomatic for pain only with palpation and not with activities of daily living or while playing sport
2. Diagnosis of bilateral apophysitis of the knee where both knees meet all of the inclusion criteria
3. Systemic fungal infections
4. Has an implanted electronic device
5. Has a known sensitivity to DSP
6. Presence of damaged skin, denuded skin, or other recent scar tissue on index knee
7. Presence of active dermatologic conditions in the affected area (e.g., eczema, psoriasis)
8. Presence of an abnormal neurological exam that indicates the subject would have a reduced ability to perceive pain (e.g. peripheral neuropathy)
9. Has a known sensitivity to electrical current
10. Is currently taking systemic steroids
11. Has had iontophoresis with DSP treatment within the past 30 days
12. Previously enrolled in this study
13. Currently enrolled in another treatment research study