A Comparison of JointRep® and Microfracture in Repair of Cartilage Lesions on the Femoral Condyle or Trochlea,

Inclusion Criteria:

• Be between 18-65 years old
• Have one or two focal articular cartilage lesion(s) (ICRS Grade 3 or 4A) on thefemoral condyles or trochlea of the index knee; patellar tracking must be normal ifthe index lesion(s) is on the trochlea. Individually, a lesion can be between 1-7cm2.If more than one lesion is present, the sum of the two lesions should not exceed 10cm2.
• Within 6 months prior to treatment, have a Magnetic Resonance Imaging (MRI) orarthroscopic confirmation of lesion(s) in the index knee.
• For patients older than 40 y.o, to have a radiological Kellgren and Lawrence (K&L)grading from a standing knee radiograph taken less than 6 months previously, Grade 1or
• If not, an actual test will be performed as part of the visit 1 procedures.
• Have a clinically stable knee, with no ligament deficiencies (<5mm side-to-sidedifference on Lachman and varus/valgus stress testing & Grade 0 or 1 on Pivot shifttest) and the meniscal rims are intact (a maximum of 50% resection is allowed)
• Be able to give voluntary, written informed consent to participate and have signed anInformed Consent Form specific to this study
• VAS pain great than or equal to 4 in the last week.
• Be willing and able to comply with all study procedures including all preoperative,post-operative and rehabilitation requirements
• If female and of child-bearing potential, must report double-barrier, contraceptiveuse (e.g. use of birth-control pill and condom) for at least 2 months prior totreatment and in the 12 months following treatment.
• If female and of child-bearing potential, have a negative pregnancy test prior to thesurgical procedure and no intention of becoming pregnant in the 12 months followingtreatment.

Exclusion Criteria:

• Have a Body Mass Index (BMI) >35kg/m2
• Have more than two lesions (ICRS grade 3 or 4A) on any surface in the index knee
• Have "kissing" or opposing lesion(s) (ICRS grade 3 or 4A) of the condyle, tibia orpatella in the index knee; additional linear lesions which bear Grade 3 or 4characteristics may be acceptable if they are determined by the Investigator to beincidental, not clinically relevant, and consistent with the subject demographic
• Have malalignment of >5 degrees varus or valgus in the index knee based on standard APx-rays requiring an osteotomy
• Have had any surgical treatment for cartilage repair in the index knee within 1 yearprior to treatment
• Have had intra-articular injections within 3 months in the index knee
• Have a diagnosis of a concomitant knee injury which may confound assessment of theindex knee (e.g., important meniscal injury)
• Have significant pain emanating from other lower body joints in the ipsilateral (hip,ankle) or contralateral (hip, knee, ankle) limb.
• Have known allergies to shellfish
• Have a known history of crystalloid or inflammatory arthropathy
• Have any condition that is unrelated to the index knee and significantly impairswalking ability (e.g., spinal stenosis, sciatica)
• Have advanced musculoskeletal disease
• Have active coagulation disorders
• Are currently using antibiotics
• Are participating concurrently in another clinical investigation, or have participatedin a clinical investigation within the last 90 days, or intend to participate inanother clinical investigation during the course of the study
• Are currently abusing drugs or alcohol or have a history of the same within the last 12 months
• Have any mental or psychological disorder that would impair their ability to completethe study questionnaires
• Are currently breastfeeding or planning to breastfeed any time during the course ofthe study
• Are currently a prisoner
• Have significant comorbidities or conditions associated with high-risk for surgical oranesthetic survival (e.g., renal failure, peripheral vascular disease, unstablecardiac disease, poorly controlled diabetes, immunosuppression, etc.)
• Have any medical condition or other circumstances, in the judgment of theinvestigator, that might interfere with the ability to return for follow-up visits,including any systemic illness, neuromuscular, neurosensory, or musculoskeletaldeficiency that would render the subject unable to perform appropriate post-operativerehabilitation
• Have any condition which, in the judgment of the Investigator, would preclude adequateevaluation of the device's safety and performance Intra-operative Exclusion Criteria: Subjects who meet any of the following intra-operative screening criteria will be excludedfrom participation in this study:
• Have lesion(s) in the index knee that are not contained (intact shoulders) and/orexceed 7 cm² in total size after debridement for a single lesion and 10cm2 for morethan one lesion, if within the same condyle or the trochlea. If only a single lesionsuitable to be included is identified, it might be between 1-7cm2.
• Minor concomitant procedures are allowed such as, but not limited to:

1. Removal of loose bodies
2. Plica excision
3. Minor synovial removing
4. Minor chondroplasty (debridement)
5. Lysis of adhesions
6. Meniscal trimming/suturing which respects the exclusion criteria.