The purpose of this research is to treat patients with knee osteoarthritis (OA) with periosteal electric dry needling (PEDN). It is also to determine the optimal "maintenance" regiment (i.e. maintenance treatments, one maintenance treatment every other month, or one maintenance treatment per month) required to maintain improvements in pain and function following PEDN. Physical therapists commonly use PEDN to treat knee OA, and previous studies suggest that this treatment is useful for reducing pain and improving function in patients with osteoarthritis. However, an appropriate maintenance treatment strategy to maintain these outcomes is presently unknown.

Patients with knee osteoarthritis will be randomized to receive periosteal electrical dry needling 1-2 treatments per week for 6 weeks (up to 10 sessions total) followed by either: 1. no maintenance treatments, 2. one maintenance treatment every other month or 3. one maintenance treatment per month.

Inclusion Criteria:

1. Adult over the age of 18 years old:

2. Report of knee pain of at least 2/10 per NPRS (0---10 scale) for >3 months

3. Report of at least 3 of the following per Altman et al. (1986) (sensitivity = 95% / specificity = 69%)

   1. Over 50 Years of age
   2. Less than 30 minutes of morning stiffness
   3. Crepitus on active motion
   4. Bony tenderness
   5. Bony enlargement
   6. No palpable warmth of Synovium

Exclusion Criteria:

1. Report of red flags to manual physical therapy to include: hypertension, infection, diabetes, peripheral neuropathy, heart disease, stroke, chronic ischemia, edema, severe varicosities, tumor, metabolic disease, prolonged steroid use, fracture, RA, osteoporosis, severe vascular disease, malignancy, etc.

2. History of physical therapy, massage therapy, chiropractic treatment, or injections for knee pain in last 4 weeks.

3. History of a partial or total knee replacement on the painful lower extremity.

4. History of a surgical procedure on either lower extremity in last 12 months.

5. Two or more positive neurologic signs consistent with nerve root compression, including any two of the following:

   1. Weakness involving a major muscle group of the lower extremity.
   2. Diminished patella or achilles tendon reflex
   3. Diminished or absent sensation to pinprick in lower extremity dermatome.

6. Involvement in litigation or worker's compensation regarding knee pain.

7. Any condition that might contraindicate the use of periosteal electric dry needling

8. The patient is pregnant.