Please select the eligibility criteria that correspond to the clinical trial below.
Title: Arthroscopic Surgery Versus Non-surgical Treatment of Osteoarthritis of the Knee
Brief Summary: The purpose of this trial is to evaluate the effectiveness of arthroscopy (lavage and debridement) in conjunction with the best available non-surgical treatment versus the best available non-surgical treatment alone (medication, health education and physical therapy) in patients with osteoarthritis of the knee.


Options:
A: Inclusion Criteria:

* Adults aged 18 to 40 years with knee pain
* Clinical history and symptoms consistent with meniscal tear and meniscal tear verified on magnetic resonance imaging (MRI)
* Deemed eligible for meniscal surgery (i.e. repair or resection) by the examining orthopedic surgeon
* Willing to participate in 12 weeks of supervised exercise twice a week or undergo surgery for the meniscal tear as soon as possible

Exclusion Criteria:

* Previous knee surgery on the affected knee
* Clinical suspicion (acute locking of knee AND/OR extension deficit) of displaced bucket-handle tear confirmed by MRI
* Fracture of the affected extremity within the previous 12 months
* Complete rupture of one or more knee ligaments.
* Participation in supervised systematic exercise for knee problems within the last 3 months prior to recruitment
* Other reasons for exclusion (Unable to understand Danish, mentally unable to participate, etc.)
B: Inclusion Criteria:

1. Age: 35 to 65 years of age.
2. A pain located on the medial joint line of the knee that has persistent at least for 3 months.
3. Pain that can be provoked by palpation or compression of the joint line or a positive McMurray sign.
4. Tear of the medial meniscus on MRI.
5. Degenerative rupture of the medial meniscus confirmed at arthroscopy.

Exclusion Criteria:

1. Acute, trauma-induced onset of symptoms.
2. Locking or painful snapping of the knee joint.
3. A surgical operation performed on the affected knee.
4. Osteoarthritis of the medial compartment of the knee (determined by clinical criteria of the ACR).
5. Osteoarthritis on knee radiographs (Kellgren-Lawrence \> 1).
6. Acute (within the previous year) fractures of the knee.
7. Decreased range of motion of the knee.
8. Instability of the knee.
9. MRI assessment showing a tumor or any other complaint requiring surgical or other means of treatment.
10. Arthroscopic assessment showing anything other than a degenerative tear of the medial meniscus requiring surgical intervention.
C: Inclusion Criteria:

* Age 35-60 years
* Knee pain for more than 2 months without a significant trauma
* Medial meniscal tear on MRI
* Eligible for arthroscopic partial meniscectomy
* Grade 0-2 radiographic severity (specification after Kellgren Lawrence)

Exclusion Criteria:

* Those requiring acute trauma surgeries, including those treated as acute cases in the ER
* Ligament injuries
* Tumours (MRI)
* Pain or other musculoskeletal comorbidities severely affecting lower extremity muscle function overriding the symptoms from the knee
* Grade 3 or 4 radiographic severity (specification after Kellgren Lawrence)
* Comorbidities excluding physical activities and exercise.
* Previous knee surgery within two years
* Not able to speak or read Norwegian, drug abuse or mental problems
D: Inclusion Criteria:

1. Idiopathic or secondary osteoarthritis of the knee as diagnosed by Altman et al 2 classification tree -83 percent sensitivity, 93percent specificity
2. Grades 2 to 4 severity of OA by radiographic evaluation- modified Kellgren and Lawrence grading system
3. Age greater than 18.

Exclusion Criteria:

1. Inflammatory or post-infection arthritis of the knee
2. Previous arthroscopy for treatment of knee OA
3. Isolated medial compartment OA Grade 3-4 with greater than 5 degrees mechanical varus -ideal candidate for high tibial osteotomy
4. Isolated lateral compartment OA Grade III-IV with greater than 5 degrees mechanical valgus -ideal candidate for high tibial osteotomy or distal femoral osteotomy
5. Grade 4 OA in at least 2 compartments and over 60 years of age -ideal candidate for total knee arthroplasty
6. Cortico-steroid injection within the last three months.
7. Major neurological deficit
8. Major medical illness -life expectancy less than 2 years or with unacceptably high operative risk.
9. Pregnant
10. Unable to speak or read English
11. Psychiatric illness that limits informed consent
12. Unwilling to be followed for 2 years

Answer: D