The correlation coefficient at the interim analysis with results for all three groups pooled, did not reach the level of statistical significance of (p<0.05).

The aim of this study is to describe changes at the site of the study patient's articular cartilage lesion on the femoral condyle with multiple magnetic resonance imaging (MRI) outcomes 6 months after treatment using one of three standard surgical treatment methods: 1) lavage debridement; 2) mechanical debridement; 3) mechanical and radiofrequency-based debridement.

Fibrillated articular cartilage are commonly detected during arthroscopy when treating knee pathologies such as a torn meniscus or a damaged anterior cruciate ligament (ACL). The severity of these lesions is graded using a scheme such as the International Cartilage Research Society (ICRS) classification system. Grade I lesions are often left untreated, while Grade IV lesions require dedicated surgical intervention. Grade II and III lesions are frequently treated when they are encountered arthroscopically.

Currently, it is not known whether treatment of fibrillated articular cartilage is beneficial or whether one procedure is superior to another. Magnetic resonance imaging is the best technique currently available for non-invasive assessment of chondral lesions. The primary aim of the proposed study is to compare post-procedure MR imaging characteristics of fibrillated articular cartilage treated using one of the three standard of care measures: 1) Washing of the knee joint with saline solution to clear blood, fluid or loose tissue (also known as lavage); 2) Lavage in addition to mechanical shaver (a manual surgical tool used by the study doctor); and 3)Lavage in addition to the Paragon device (RF-based microdebridement), which may also be used with a mechanical (or manual) surgical tool. The secondary aim is to determine the association between imaging features and clinical outcomes.

Inclusion Criteria:Screening

• Age between 18 and 60 years
• BMI <35
• Meniscal tear (medial or lateral) diagnosed by H+P exam and/or imaging in the index knee
• No severe joint space narrowing (IKDC Classification) seen on weight-bearing AP X-ray in the index knee
• No avascular necrosis in the index knee as evidenced by preop MRI obtained within 6 months prior to randomization
• No Varus (>10 degrees) or Valgus (>15 degrees)knee deformities as seen by AP X-ray in the index knee
• Minimal or no abnormality of contralateral knee as shown by clinical exam and/or imaging
• Candidate for unilateral arthroscopic treatment of the knee
• Visual Analog Scale (VAS) pain score of 30 mm or greater in the index knee at the time of screening
• Must be able to undergo MRI at required time points per appendix D
• Physically and mentally willing and able to comply with study requirements
• Must be willing and able to follow the standardized rehabilitation protocol (Appendix C)
• Subject must sign IRB approved informed consent form

Arthroscopy Inclusion Criteria:

• Arthroscopic confirmation of ICRS Grade II or III chondral lesion on the medial or lateral femoral condyle

Exclusion Criteria: Screening

• Knee instability, malalignment, or patellar tracking dysfunction in the index knee
• Inflammatory rheumatoid arthritis or other systemic inflammatory arthritis in the index knee or contralateral knee
• Previous total meniscectomy in the index knee
• Previous surgical treatment of the index knee by arthroscopy less than 2 years prior to treatment by this study
• Previous total meniscectomy
• Previous knee tendon and/or ligament repair or patellar surgery of index knee
• Previous microfracture or bone marrow stimulation of the index knee
• Previous unsuccessful osteotomy in the index knee
• Presence of fractures, osteocysts or osteolysis in the index knee
• Presence of osteoarthritis in the index knee
• Pre-existent osteoarthritis of weight-bearing joints (e.g. hips or contralateral knee) that adversely affects gait
• Participation in another clinical study
• Terminally ill
• Drug therapy for the index knee with systemic steroid therapy, steroid intra-articular therapy or intra-articular hyaluronic acid therapy within 2 months of enrollment into this study
• Receiving narcotic pain medication by prescription for other conditions unrelated to knee injury
• Contralateral knee involvement causing abnormal ambulation and non-compliance with rehabilitation
• Pregnant or suspected pregnant
• Coagulation disorder or patient is receiving anti-coagulants, which cannot be safely stopped for 14 days (7 days prior to surgery and 7 days post-surgery)

Arthroscopy Exclusion Criteria:

• Presence of Grade IV chondromalacia anywhere in the index knee
• ACL, PCL or MCL tear of the index knee
• Osteochondritis dissecans (OCD)of the index knee
• Meniscal tear requiring total meniscectomy
• Evidence of osteoarthritis in the index knee