The Knee Tibiofemoral Joint Jeremy, Brittany, Spirit, Kelsey Medial Lateral head head Popliteal fossa Surface Anatomy Medial head Lateral head Surface Anatomy Patella Surface Anatomy: Tendons ● Biceps Femoris ● Semimembranosus ● Semitendinosus Anterior View Posterior View Femur ● Lateral Condyle ● Medial Condyle ● Lateral Epicondyle Intercondylar Medial Fossa ● Medial Epicondyle Lateral Epicondyle ● Intercondylar Fossa Epicondyle Lateral Condyle Medial Condyle Medial Lateral Condyle Condyle Intercondylar Eminence Tibia Tibial Tuberosity ● Lateral Condyle ● Medial Condyle ● Tibial Tuberosity ● Intercondylar Eminence Fibula Head ● Head ● Lateral Malleolus Lateral Malleolus Patella Base Anterior ● Base ● Apex Apex ● Articular Surface Posterior Articular Surface Meniscus ● Act as cushions ● Stabilize the knee joint during flexion, extension, and lateral movements Meniscus ● Medial meniscus is more “c” shaped and larger; ● Lateral meniscus is more circular and smaller Meniscus ● Medial meniscus is more “c” shaped and larger; ● Lateral meniscus is more circular and smaller. Fibular Collateral Ligament Posterior Cruciate Ligaments Ligament Collateral ligaments ● Resist lateral forces to knee ● Also known as Lateral Collateral Ligament (LCL) and Medial Collateral Ligament (MCL) Transverse ligament ● Holds meniscus in place during knee extension Cruciate (“cross”) ligaments Transverse Ligament ● Anterior Cruciate Ligament (ACL) - resists anterior translation and medial rotation of the tibia on the femur Tibial Collateral Ligament ● Posterior Cruciate Ligament (PCL) - resists posterior translation of tibia on femur Ligaments (part 2) Clinical Concerns: Torn ACL ● Occurs in extension + lateral rotation of tibia on femur. ● Common injury in sports that involve planting and changing directions or contact to knee when extended. ● Women more prone to ACL tears due to wider Q-angle. ● Terrible triad - ACL, MCL, and meniscus are torn Ligaments (part 3) Popliteal Ligaments ● Tightens the posterior capsule of the knee Oblique Arcuate Bursae ● Suprapatellar: ○ Between the femur and quadriceps tendon ● Prepatellar: ○ Between patella and skin ● Deep Infrapatellar: ○ Between Tibia and patellar ligament ● Subcutaneous Infrapatellar: ○ Between tibial tuberosity and skin Suprapatellar bursa ● Located between the femur and quadriceps tendon Prepatellar bursa ● Located between patella ● and skin Deep Infrapatellar bursa ● Located between tibia and patellar ligament Subcutaneous Infrapatellar bursa ● Located between tibial tuberosity and skin Sciatic Nerve ● Largest single nerve in the human body ● Originates from the lumbar & sacral plexuses ○ Roots: L4 &L5, S1-S3 ● Branches into tibial nerve & Sciatic Common common fibular (peroneal) Nerve Fibular nerve Nerve ● Together with its terminal Tibial branches, innervates muscles of Nerve the posterior thigh, entire leg and entire foot Posterior View Superficial Fibular Common Peroneal (Peroneal) Nerve Nerve ● Terminal branch of the Superficial Fibular common peroneal nerve (Peroneal) ● Innervates lateral lower leg Nerve and the dorsum of the foot and ankle ● Roots ○ L4-S1 Anterior View Deep Fibular Common Deep Fibular Peroneal (Peroneal) Nerve (Peroneal) Nerve Nerve ● Branches from Common Superficial Fibular Peroneal Nerve (Peroneal) ● Innervates the muscles of the Nerve anterior compartment of the leg and webbed space of skin between the first and second toes ● Roots ○ L4-L5 Anterior View Superficial & Deep Fibular (Peroneal) Nerves Tibial Nerve ● Branches from sciatic nerve and follows the midline of the lower leg to the heel Femoral Nerve ● Roots: L2-L4 ● Largest nerve in the lumbar plexus ● Innervates: Muscles that extend the knee (Rectus Femoris, Vastus Lateralis, Vastus Intermedius, Vastus Medialis); also muscles that flex the hip (Iliacus, Psoas Major, Pectineus, Sartorius) Tendons: Quadriceps Femoris Composed of 4 quadriceps muscles: ● Rectus Femoris ● Vastus Lateralis, ● Vastus Intermedius ● Vastus Medialis Rectus Femoris Nerve: Femoral Nerve Roots: L2 & L4 Action: Knee extension; Hip flexion Origin: Anterior inferior iliac spine Insertion: Patella via quadriceps tendon & tibial tuberosity via patellar ligament Rectus Femoris Synergists: Hip Flexion: Iliopsoas, Pectineus, TFL, Sartorius, Adductor (Longus & Brevis) Knee Extension: Vastus (all) Antagonists: Hip Extension: Glute Max, Semimembranosus, Semitendinosus, Biceps Femoris Knee Flexion: Semimembranosus, Semitendinosus, Biceps Femoris, Gracilis, Gastrocnemius, Popliteus, Sartorius Vastus Intermedius Nerve: Femoral Nerve Roots: L2 & L4 Action: Knee extension Origin: Anterior ⅔ and lateral shaft of femur Insertion: Patella via quadriceps tendon & tibial tuberosity via patellar ligament Vastus Intermedius Synergists: Knee Extension: Rectus Femoris, Vastus (Lateralis & Medialis) Antagonists: Knee Flexion: Biceps Femoris, Semimembranosus, Semitendinosus, Gracilis, Gastrocnemius, Popliteus, Sartorius Vastus Medialis O: Linea aspera of femur I: Patella via quadriceps tendon, tibial tuberosity via patellar ligament N: Femoral nerve R: L2-L4 A: Extends the knee Vastus Medialis S: Extension: Rectus Femoris, Vastus Lateralis, Vastus Intermedius A: Extension: Semimembranosus, Semitendinosus, Biceps Femoris, Gracilis, Gastrocnemius, Popliteus, Sartorius Vastus Lateralis O: Intertrochanteric line and linea aspera of femur I: Patella via quadriceps tendon, tibial tuberosity via patellar ligament N: Femoral nerve R: L2-L4 A: Extends the knee Vastus Lateralis S: Extension: Rectus Femoris, Vastus Medialis, Vastus Intermedius A: Extension: Semimembranosus, Semitendinosus, Biceps Femoris, Gracilis, Gastrocnemius, Popliteus, Sartorius Biceps Femoris O: Long Head: Ischial Tuberosity Short Head: Linea Aspera of Femur I: Head of the fibula & lateral condyle of tibia A: Long Head: Extends hip & flexes knee Short Head: Flexes knee & laterally rotates hip Laterally rotates flexed knee N: Tibial Nerve (LH) & Fibular Nerve (SH) R: L5, S1 & S2 Biceps Femoris S: Hip Extension: gluteus maximus, semitendinosus, semimembranosus, adductor Lateral Rotation: gluteus maximus, piriformis, iliopsoas, sartorius Knee Flexion: semitendinosus, semimembranosus, gracilis, sartorius, gastrocnemius A: Hip Flexion: Rectus femoris, iliopsoas, pectineus, TFL, Sartorius Medial Rotation: gluteus (medius & minimus), TFL, adductor (magnus, longus, brevis), pectineus, gracilis Knee Extension: Vastus (medialis, lateralis, intermedius), rectus femoris Semitendinosus O: Ischial Tuberosity I: Proximal medial shaft of tibia at Pes Anserinus tendon A: Flexes knee, medially rotates flexed knee & extends hip N: Tibial Nerve R: L5, S1 & S2 Semitendinosus S: Knee Flexion: Biceps femoris, semimembranosus, gracilis, sartorius, gastrocnemius, popliteus Hip Extension: Gluteus maximus, biceps femoris, semimembranosus Medial Rotation: Semimembranosus, gracilis, sartorius, popliteus A: Knee Extension: Rectus femoris, Vastus (medialis, lateralis, intermedius) Hip Flexion: Rectus femoris, iliopsoas, pectineus, sartorius Lateral Rotation: Biceps Femoris Semimembranosus O: Ischial Tuberosity I: Posterior medial condyle of tibia A: Flexes knee, medially rotates flexed knee & extends hip N: Tibial Nerve R: L5, S1 & S2 Semimembranosus S: Knee Flexion: Biceps femoris, semimembranosus, gracilis, sartorius, gastrocnemius, popliteus Hip Extension: Gluteus maximus, biceps femoris, semimembranosus Medial Rotation: Semimembranosus, gracilis, sartorius, popliteus A: Knee Extension: Rectus femoris, Vastus (medialis, lateralis, intermedius) Hip Flexion: Rectus femoris, iliopsoas, pectineus, sartorius Lateral Rotation: Biceps Femoris Popliteus ● Deep knee flexor muscle ● Action: unlocks the knee (flexion) when in full extension (hyperextension) ● Innervation: Tibial Nerve (roots L4-S1) ● Origin: Lateral condyle of femur and lateral meniscus ● Insertion: posterior tibia ● Synergists: Gracilis, Sartorius, Semitendinosus, Semimembranosus, Biceps Femoris, Gastrocnemius ● Antagonists: Rectus Femoris, Vastus Lateralis, V. Intermedialis, V. Medialis Gastrocnemius ● Superficial muscle which names means “leg belly.” It gives the calf its shape ● Action: Knee flexion and ankle plantarflexion ● Innervation: Tibial Nerve (roots S1-S2) ● Origin: Medial head - Superior to medial condyle of femur Lateral head - lateral condyle of femur ● Insertion: calcaneus via calcaneal (Achilles) tendon Gastrocnemius ● Synergists: Knee flexion: Biceps Femoris, Sartorius, Gracilis, Semitendinosus, Semimembranosus, Popliteus Plantarflexion: Soleus, Plantaris, Tibialis Posterior, Fibularis longus, Fibularis Brevis ● Antagonists: Knee extension: Rectus Femoris, Vastus Lateralis, Vastus Intermedialis, Vastus Medialis Dorsiflexion: Extensor Digitorum Longus, Tibialis Anterior, Extensor Hallucis Longus, Fibularis Tertius Arteries of the knee Femoral: supplies lower limbs Popliteal: supplies capsule and ligaments of knee joint Anterior Tibial: supplies anterior compartment of the leg; dorsal surface of the foot Posterior Tibial: supplies posterior compartment of the leg; plantar surface of the foot Fibular (Peroneal): supplies blood to lateral compartment of leg Dorsalis Pedis: supplies dorsal surface of foot Arteries of the knee Femoral Popliteal Anterior Tibial Posterior Tibial Dorsalis Pedis Fibular/Peroneal Veins of the knee Small Saphenous: superficial vein; passes through Gastrocnemius Great Saphenous: superficial vein; longest vein in the body Anterior Tibial: follows artery Posterior Tibial: follows artery Fibular (Peroneal): follows artery Popliteal: follows artery Femoral: follows artery Veins of the knee Fibular/Peroneal Anterior Tibial Posterior Tibial Popliteal Small Saphenous Femoral Great Saphenous External Iliac Questions?.