Evaluation of Subchondroplasty™ for Defects Associated With Bone Marrow Lesions

Inclusion Criteria: * Subject is 40-70 of age and skeletally mature * Subject BMI is \< 40 * Subject has experienced pain in knee for at least 3 months * BML is confirmed on T2 weighted MR Imaging by presence of white signal * Subject has single BML of tibia, single BML of femur, or adjoining BML's of tibia \& femur * Baseline KOOS pain subscore is ≤65 * Subject's involved knee alignment is defined radiographically as one of the following: Neutral, ≤ to 7 degrees mechanical varus or \< 7.5 degrees mechanical valgus * Subject's ACL and PCL ligaments are intact * Subject has failed no more than one operative treatment on treatment knee, and none within 6 months prior to enrollment * Subject is willing and able to sign a written consent form * The subject has the mental capacity and the willingness to comply with the specified follow-up evaluations, and can be contacted by telephone by the site personnel. Exclusion Criteria: * Surgeon deems subject's pain to be primarily related to an alternate condition such as a baker cyst, synovitis, meniscal pathology, or other * BML caused by acute trauma * Subject is not neurologically intact (sensory, motor, and reflex deficit) * Subject is insulin dependent * Subject has a history of any invasive malignancy (except non-melanoma skin cancer), unless treated with curative intent and with no clinical signs or symptoms of the malignancy for 5 years * Subject with primary bone tumor in the knee area * Subject anticipates having a lower extremity surgery other than the investigational surgery during the course of the study * Subject has a history of substance abuse * Subject is currently involved in another study or have received investigational product or treatment within the last 30 days * Subject is pregnant or planning on becoming pregnant during the study period * Subject is accepting workers' compensation