L3 Knee PDF - Knee Anatomy Lecture Notes

Knee Joint Popliteal Region Moore pp. 752-756, 803-812 John Gassler DPT DOSYS 702 Lecture 3 January 8, 2025 2 2  Learning Objectives At the end of this lecture the student will be able to: Name...

Knee Joint Popliteal Region Moore pp. 752-756, 803-812 John Gassler DPT DOSYS 702 Lecture 3 January 8, 2025 2 2  Learning Objectives At the end of this lecture the student will be able to: Name and identify the important bony landmarks of the knee region. Name and identify the structure of the knee joint capsule, named ligaments, menisci and bursae. Describe the location of muscles that attach at the knee region. Name the boundaries of the popliteal fossa, the contents, and their relationships in it. 3 3  Knee Joints Anterior Articulations: Patellofemoral Tibiofemoral Medial Lateral The superior tibiofibular articulation is not a part of the knee joint complex 4 Gilroy Fig 32.2A, p. 428 4  Knee Joints Lateral Tibiofemoral Patellofemoral The superior tibiofibular articulation is not a part of the knee joint complex Gilroy Fig 32.2C, p. 429 5 5  Distal Femur Anterior Medial and lateral condyles Medial and lateral epicondyles Adductor tubercle Patellar articular surface Gilroy Fig 31.4A, p. 406 6 6  Distal Femur Posterior Medial and lateral condyles Medial and lateral epicondyles Intercondylar notch Adductor tubercle 7 Gilroy Fig 31.4B, p. 406 7  Distal Femur Patellar and tibial surfaces are separate Femoral condyles articulate with tibial condyles Gilroy Fig 31.4D, p. 407 8 8  Patella Posterior Posterior surface of patella articulates with anterior surface of femur (trochlea) Gilroy Fig 32.3B, p. 429 9 9  Proximal Tibia Superior Gilroy Fig 32.1C, p. 427 10 10  Knee Radiology Sunrise view 11 Find: Medial and lateral femoral condyles Medial and lateral femoral epicondyles Intercondylar groove on femur Patella Medial and lateral tibial condyles Tibial tuberosity Tibial plateau Intercondylar eminences Head of fibula 11 Knee Joint Capsule Anterior Medial Retinaculum Lateral Retinaculum Retinacula reinforce the joint capsule medial and lateral to the patellar ligament 12 Gilroy Fig 32.5, p. 430 12  Suprapatellar pouch Knee Joint Capsule Anterior - Removed Synovial membrane lines the inside of the fibrous capsule not covered by articular cartilage Note suprapatellar pouch which extends superiorly deep to the quadriceps tendon Gilroy Fig 32.14, p. 436 13 13 Knee Joint Capsule Posterior The posterior capsule is strengthened by two ligaments: The oblique popliteal ligament is formed by part of the semimembranosus tendon The arcuate popliteal ligament arches over the popliteus muscle/tendon Gilroy Fig 32.6, p. 431 14 14 Knee Joint Capsule Lateral Iliotibial Tract (Band) Attaches to distal femur, patella, and lateral tibial tubercle Blends with knee joint capsule at the lateral retinaculum * Gerdy’s tubercle * Gerdy’s tubercle – also known as the lateral tibial tubercle 15 Gilroy Fig 31.16, p. 419 15  Knee Joint Synovial Cavity Suprapatellar pouch (bursa) Proximal extension of synovial cavity Lies deep to quadriceps tendon Normal – 0.5 – 4.0 cc of synovial fluid Gilroy Fig 32.13, p.436 16 16 Synovial Membrane Tibial Attachment Cruciate ligaments attach to the intercondylar region Menisci attach to intercondylar region Gilroy Fig 32.8B, p. 433 17 17  Menisci Medial meniscus oval larger narrow Lateral meniscus round smaller wide Weight-bearing – The menisci bear some of the weight of the body that is transferred from the femoral condyles to them. If a meniscus is removed, the body weight is borne on a smaller area of articular cartilage. This predisposes that cartilage to premature destruction. 18 18  Menisci Synovial membrane Blood supply – only outer edge of menisci are supplied with blood. Inner portion has no blood supply. If the inner portion is Common meniscus tears torn, there is poor chance of healing. 19 19  Infrapatellar Fat Pad Cushion between patellar ligament and anterior surface of tibia 20 Gray’s Fig 6.69, p. 606 20 Collateral Ligaments Cruciate Ligaments Anterior Medial (tibial) Collateral Lateral (fibular) Collateral Anterior Cruciate Posterior cruciate 21 Gilroy Fig 32.10A, p. 434 21  Collateral Ligaments Cruciate Ligaments Posterior Medial (tibial) Collateral Lateral (fibular) Collateral Anterior Cruciate Posterior cruciate Gilroy Fig 32.10B, p. 434 22 22  Medial Collateral Ligament Medial epicondyle of femur to medial tibia deep fibers attach to medial meniscus Tear in medial collateral ligament may also damage the medial meniscus Gilroy Fig 32.7A, p. 432 23 23 Lateral Collateral Ligament Lateral epicondyle of femur to head of fibula Does not attach to lateral meniscus 24 Gilroy Fig 32.7B, p. 432 24  Valgus and Varus Stress Tests These stress tests examine the integrity of the collateral ligaments of the knee Valgus stress test – tests integrity of the medial collateral ligament Varus stress test – tests the integrity of the lateral collateral ligament 25 25  Collateral and Cruciate Ligaments Outer aspect of medial meniscus is attached to the inner surface of the medial collateral ligament Gilroy Fig 32.8A, 26 p. 433 26 Cruciate Ligaments -Anterior Anterior intercondylar area of tibia to lateral condyle of femur 27 Gilroy Fig 32.11, p. 435 27  Cruciate Ligaments Posterior Posterior intercondylar area of tibia to medial condyle of femur Gilroy Fig 32.10B, p. 434 28 28  Cruciate Ligament Function F ACL PCL T ACL prevents hyperextension of knee or posterior or anterior Both ligaments provide stability at the movement movement knee joint throughout the ROM of femur of femur 29 29  Cruciate Ligament Tears ACL Tear PCL Tear Sag sign 30 Anterior/Posterior Drawer Test 30  Other Knee Joint Structures Prepatellar bursitis Gray’s Fig 6.72, p. 609 31 31  Patellofemoral Joint Forces Knee Flexion < 90⁰ Knee Flexion > 90⁰ 32 32  Knee Joint Rotation When the knee is non-weight bearing and flexed to 90°, the tibia can rotate medially and laterally on the femur Medial hamstrings medially rotate, biceps femoris laterally rotates 33 33 Q Angle Angle between vertical line through patella and line parallel to shaft of femur (use ASIS as proximal landmark) Excessive Q angle contributes to lateral dislocation of the patella 34 34  Tibiofemoral Joint Genu valgum Genu varum 35 35  Degenerative Arthritis of the Knee Total Knee Arthroplasty (TKA) Normal Knee OA 36 36  Popliteal Fossa Covered by popliteal fascia Small (lesser) saphenous v. pierces crural fascia in leg and travels up to popliteal fossa Usually drains into popliteal v. May travel up into posterior thigh to drain into perforating veins 37 37  Popliteal Fossa Borders: Superomedial – semitendinosus, semimembranosus Superolateral – biceps femoris Inferomedial – medial head, gastrocnemius Inferolateral – lateral head, gastrocnemius, plantaris Floor – distal femur Roof – popliteal fascia 38 Gilroy Fig 32.20A, p. 440 38 Popliteal Fossa Contents Superficial to deep: Sciatic nerve branches Popliteal vein Popliteal artery Additionally: popliteal lymph nodes, fat 39 39  Popliteal Fossa Sciatic Nerve Splits into tibial and common fibular nerves Tibial n. – midline Common fibular n. – lateral – runs along biceps femoris tendon 40 Gilroy Fig 29.36B, p. 466 40  Popliteal Fossa Femoral Artery Femoral a. is anterior to femoral v. in adductor canal, and is more superficial -Same relationship exists as vessels pass through adductor hiatus -in popliteal fossa, popliteal a. is still anterior to popliteal v., but artery is now deep to vein -Tibial n. is superficial to vessels Gray’s Fig 6.79B, p. 616 41 41 Genicular Anastomosis Knee Supplies knee joint and surrounding tissues Superior medial genicular a. Superior lateral genicular a. Inferior medial genicular a. Inferior lateral genicular a. Middle genicular a. 42 Gilroy Fig 34.1B, p. 466 42  Popliteal Region Pathology Popliteal (Baker’s) Cyst: Outpouching of synovial membrane through the posterior knee joint capsule Deep vein thrombosis (DVT) Popliteal vein is a common place for DVTs (blood clots) to develop in the lower limbs 43 43