 The menisci are C-shaped discs of fibrocartilage that are interposed between the condyles of the femur and tibia.  Primary function is load transmission or weight bearing.  Secondary function is shock absorption during gait.  Contribute to joint stability and lubrication.

 Nerve endings provide proprioceptive feedback for joint position.  A tear or loss of the menisci, either partial or complete, hinders their ability to perform.  A twisting injury to the knee with the foot in weight bearing can injure the menisci.  The outer 20% is vascular – peripheral injuries may heal.

 Clinical Signs and Symptoms  Local medial or lateral joint pain  Limited knee range of motion  Crepitus upon movement  Joint effusion  Knee buckling  Pain on walking up and down stairs  Pain on squatting

 Procedure: Patient prone. Flex leg to 90 degrees. Grasp the patient’s ankle and apply downward pressure while you internally and externally rotate the leg.  Positive Test: Flexing the knee distorts the meniscus. Downward pressure further stresses the meniscus. Pain or crepitus on either side indicates a meniscus injury on that side.

 Procedure: Patient supine. Flex leg. Externally rotate the leg as you extend. Internally rotate the leg as you extend.  Positive Test: Flexion and extension distort the meniscus. Adding external and internal rotation further distorts the meniscus. A palpable or audible click indicates injury of the meniscus.

 The major ligaments of the knee are the anterior and posterior cruciate and the medial and lateral collateral ligaments.  Ligament injuries are among the most serious knee disorders.  Usually due to traumatic stress to the knee while bearing weight.

 Valgus stress may sprain or tear the medial collateral ligament.  Varus stress may sprain or tear the lateral collateral ligament.  Both of these stresses with a rotational force may sprain or tear the anterior and/or posterior cruciate ligaments.

 Clinical Signs and Symptoms  Knee pain  Limited range of motion  Difficulty in weight bearing  Joint effusion  Knee giving out; chronic unstable knee

 Procedure: Patient supine. Flex the leg and place the foot on the table. Grasp behind the knee and pull and push on the leg. Hamstring tendons must be relaxed.  Positive Test:

 More than 5 mm of tibial movement on the femur when leg is pulled - injury or tear to one or more of the following structures is indicated:  Anterior cruciate ligament  Posterolateral capsule  Posteromedial capsule  Medial collateral ligament (more than 1cm movement)  Iliotibial band  Posterior oblique ligament  Arcuate-popliteus complex

 If excessive movement occurs when the leg is pushed, an injury to one or more of the following structures in indicated:  Posterior cruciate ligament  Arcuate-popliteus complex  Posterior oblique ligament  Anterior cruciate ligament

 Procedure: Patient supine. Knee 30° flexion. Grasp thigh with one hand to stabilize. Grasp tibia with opposite hand and pull forward.  Positive Test: Softened feel or anterior translation of the tibia suggests a possible tear of:  Anterior cruciate ligament  Posterior oblique ligament

 Procedure: Patient prone. Flex leg to 30°. Stabilize posterior thigh with one hand. Push tibia posterior with the other hand.  Positive Test: Posterior pressure on the tibia stresses the posterior cruciate ligament. A soft end feel and posterior translation of the tibia are positive findings.

 Procedure: Patient prone. Flex leg to 90°. Stabilize patient’s thigh with your knee. Pull on the ankle while internally and externally rotating the leg.  Positive Test: Distraction of the knee takes pressure off the meniscus and puts strain on the medial and lateral collateral ligaments (non-specific).

 Procedure: Patient supine. Stabilize medial thigh. Grasp lower leg and push medially.  Positive Test: Excessive movement of the tibia away from the femur indicates a possible tear of:  Tibial collateral ligament  Posterior meniscofemoral ligament  Posterior medial capsule  Anterior cruciate ligament  Posterior cruciate ligament

 Procedure: Patient supine. Stabilize lateral thigh. Grasp lower leg and pull it laterally.  Positive Test: Excessive movement of the tibia away from the femur indicates a possible tear of:  Fibular collateral logaments  Posterolateral capsule  Posterior cruciate ligament  Anterior cruciate ligament

 Grade 0No joint Opening  Grade 1+Less than 0.5 cm joint opening  Grade to 1.0 cm joint opening  Grade 3+More than 1cm joint opening

 The patella protects the anterior aspect of the knee.  It acts as a fulcrum that increases the mechanical advantage of the quadriceps.  The patella lies in the trochlear groove. With normal flexion and extension it tracks smoothly in the groove.

 Many causes of anterior knee pain involve abnormal tracking of the patella or direct trauma to the patella.  Patellofemoral injuries include fractures, dislocations, malalignment syndrome, chondromalacia patellae, and patellofemoral arthritis.

 Clinical Signs and Symptoms  Anterior knee joint pain  Knee joint effusion  Popping sensation  Joint crepitus  Discomfort with stair climbing  Knee buckling

 Procedure: Patient supine. Move patella medially and laterally while pressing down.  Positive Test:  Pain under the patella - chondromalacia patellae, retropatellar arthritis, or a chondral fracture.  Pain on the patella – osteochondritis.  Pain over the patella – prepatellar bursitis.

 Procedure: Patient supine. Manually displace the patella laterally.  Positive Test: A look of apprehension on the patient’s face and a contraction of the quadriceps muscle indicates a chronic tendency to lateral patella dislocation. Pain is also present with this test.

 Effusion in and around the knee may be caused by trauma, infection, degenerative joint disease, rheumatoid arthritis, gout, or pseudogout.  The fluid may contain blood, fat, lymphocytes, and crystals such as urate, pyrophosphate, and oxalate.

 Clinical Signs and Symptoms  Knee pain on walking  Anterior knee inflammation  Knee joint warmth to touch

 Procedure: With one hand, encircle and press down on the superior aspect of the patella. With the other hand, push the patella against the femur with your finger.  Positive Test: If fluid is present in the knee, the patella will elevate when pressure is applied. When the patella is pushed down, it will strike the femur with a tap.