Inspection Skin Discoloration, wounds, gross deformity, or previous scars Soft Tissues Swelling, muscle atrophy, symmetry Bony Length - compare to contralateral side Position - genu varum or valgus; flexion contractures Gross deformity or malalignment Gait Varus thrust can indicate LCL or PLC insufficiency or injury Antalgic (painful) shortened stance phase on affected side Patella tracking Flexed knee gait from tight achilles tendon or hamstrings Palpation Bony joint line tenderness to palpation medially or laterally patella translation facet pain to palpation tibial tubercle Soft tissue structures pes anserine bursea patellar tendon quadriceps tendon iliotibial band collateral ligaments popliteal fossa pain with Baker's cyst or popliteal aneurysm Swelling pre-patellar bursitis intra-articular effusion patella balloting milking traumatic hemarthrosis intra-articular fracture or ligament rupture Neurovascular Motor knee flexion - sciatic nerve knee extension - femoral nerve foot plantarflexion - tibial nerve foot dorsiflexion - deep peroneal nerve Sensory medial thigh - obturator nerve anterior thigh - femoral nerve posterolateral leg - sciatic nerve dorsal foot - peroneal nerve plantar foot - tibial nerve Pulses popliteal dorsal pedis posterior tibial Reflexes patellar (L4) hypoactive / absent is concerning for L4 radiculopathy hyperactive may indicate UMN injury ROM Flexion 125-135 deg Extension 0-10 deg hyperexension Rotation (stabilize femur) 10-15 deg internal and external tibial rotation Special Tests Anterior Cruciate Ligament Lachman's test most sensitive test for ACL rupture flex knee to 20-30 deg, translate tibia with anteriorly directed force grading login to view 4 more bullets anterior drawer flex knee to 90 deg, translate tibia with anteriorly directed force laxity in anterior translation indicates ACL injury pivot shift patient is supine with the knee fully extended place an internal rotation and valgus force on the proximal tibia while flexing the knee clunk with flexion indicates ACL injury login to view 1 more bullet ITB login to view 2 more bullets Posterior Cruciate Ligament posterior drawer flex knee to 90 deg, posteriorly directed force on tibia posterior sag place the patient supine, hip at 45 deg, and knee at 90 deg view the knee from the lateral position posterior translation of the tibia in relation to the femur, indicates a PCL injury quadriceps active with the patient supine, flex the knee to 90 deg and have the patient fire their quadriceps posterior subluxed tibia will translate anteriorly if PCL is deficient reverse pivot shift with the patient supine, flex the knee to 45 deg, ER and apply a valgus force to the proximal tibia and extend the knee a clunk with knee extension indicates a PCL injury Collateral Ligaments valgus stress lateral force to knee at 0 and 30 deg login to view 2 more bullets varus stress medial force to knee at 0 and 30 deg login to view 2 more bullets Meniscus joint line tenderness most sensitive test for meniscal tear when pain is present palpate medial and lateral joint lines McMurray's test place knee into flexion, and internal rotation, then extend the knee login to view 1 more bullet place knee into flexion, and external rotation, then extend the knee login to view 1 more bullet Apley's compression test with the patient prone, place the knee at 90 deg, then compress and rotate the leg login to view 1 more bullet Patellofemoral Joint patella displacement translate patella medially or laterally divide patella into 4 quadrants login to view 1 more bullet patella apprehension relax the quads and place laterally directed force on patella pain or apprehension would indicate MPFL or medial retinacular injury J-sign extend the patient's knee from a flexed position maltracking noted if patella is laterally displacing in full extension patella grind test have the patient activate their quadriceps while placing a compression force on the patella when the knee is in full extension pain would indicate patellar/trochlear OCD, chondromalacia, or arthritis Extensor Mechanism straight leg raise patient supine, have them raise the foot off the bed and hold it in position light resistance can test strength inability to perform suggests quadriceps or patellar tendon injuries