Tricompartmental OA
Osteoarthritis affecting all three compartments of the knee: medial (inner), lateral (outer), and patellofemoral (kneecap). Often indicates more advanced disease.
Extended Definition
The knee has three compartments where bones meet and cartilage can wear:
- Medial compartment - Inner knee (femur meets tibia)
- Lateral compartment - Outer knee (femur meets tibia)
- Patellofemoral compartment - Front knee (kneecap meets femur)
Tricompartmental OA means all three are affected—typically indicating more widespread, advanced disease.
Clinical Significance
- More severe symptoms than single-compartment OA
- Greater functional limitation
- Affects treatment options - Partial knee replacement not suitable
- May respond to HA injections - Lubricates entire joint
Imaging
X-rays typically show:
- Narrowed joint space in all compartments
- Bone spurs around entire joint
- Possible varus or valgus deformity
Treatment Approach
Even with tricompartmental OA, conservative treatments including HA injections may provide relief. When surgery becomes necessary, total knee replacement (not partial) is typically indicated.
Related Terms
More Conditions Terms
View allBilateral Arthritis
Arthritis affecting the same joint on both sides of the body, such as both knees or both hips. Common in osteoarthritis due to similar wear patterns.
Bone Spur
A smooth, bony growth that develops along the edges of bones, especially in joints affected by osteoarthritis. Also called an osteophyte.
Bone-on-Bone
A colloquial term describing advanced osteoarthritis where cartilage has worn away completely, allowing direct contact between bone surfaces. Often painful and may require surgery.
Chondromalacia
Softening and deterioration of cartilage, most commonly affecting the underside of the kneecap. Often considered an early stage of patellofemoral arthritis.
Crepitus
A crackling, popping, or grinding sensation or sound that occurs during joint movement, often felt or heard when bones with damaged cartilage rub together.