Clarification of Terms

Transcription

1 The Knee

2 Clarification of Terms The knee consists of: The tibiofemoral joint Patellofemoral joint Mansfield, p273

3 Osteology of the Knee Distal Femur Proximal tibia and fibula Patella

4 Osteology of the Knee Distal femur (ADDuctor tubercle) Right Femur

5 Osteology of the Knee The proximal tibia & fibula The medial and lateral condyles of the tibia form the shallow articulations with the distal femur Fibular Head Tibial Tuberosity The intercondylar/intercondyloid eminence the attachment point for the cruciate ligaments Interosseous Membrane

6 Osteology of the Knee Patella

7 Joint Structure Tibiofemoral Joint Articulation between the large condyles of the distal femur and the relatively flat proximal tibia Patellofemoral Joint Articulation between the patella and distal femur Mansfield, p273

8 Joint Structure: Alignment Genu valgum refers to a frontal deviation of the position of the knee. Commonly referred to as knock-knee due to the distal segments being positioned more laterally than normal Genu varum refers to a frontal deviation of the position of the knee. Commonly referred to as bow-leg is the opposite. Lippert, p294 & Mansfield, p278

9 Joint Structure: Alignment Genurecurvatum: Hyperextension of the tibiofemoral joint placing excessive stress on the structures in the popliteal space Tibial nerve Popliteal Vein Popliteal Artery Common Peroneal Nerve

10 Joint Structure: Alignment Q Angle * angle between the quadriceps muscle and the patellar tendon * draw a line from the ASIS to the midpoint of the patella and from the tibial tuberosity to the midpoint of the patella * tends to be greater in females due to wider pelvis Lippert, p285

11 Joint Movement Tibiofemoral Joint: Osteokinematics: flexion, extension Internal and external rotation Arthrokinematics: Open chain = Closed chain = (hint: convex distal femoral condyles and concave proximal tibial plateau) Lippert, p284 & Mansfield, p284

12 Joint Movement Patellofemoral Joint Osteokinematics n/a Arthrokinematics The smooth posterior surface of the patella glides over the femur It glides and tilts in all 4 directions Lippert, p285

13 Supporting Structures ACL & PCL (Sagittal plane stability) MCL & LCL (Frontal Plane stability) Posterior capsule Medial and lateral menisci

14 Supporting Structures Anterior Cruciate Ligament (ACL) Keeps femur from moving posteriorly on tibia and from tibia from moving anteriorly on femur Tightens during extension, preventing hyperextension Posterior Cruciate Ligament (PCL) Keeps femur from moving anteriorly on tibia and from tibia from moving posteriorly on femur Tightens during flexion Lippert, p288

15 Supporting Structures: ACL & PCL

16 Supporting Structures Medial Collateral Ligament (MCL) Lateral Collateral Ligament (LCL) Flat broad ligament attaching the medial condyles of femur and tibia It protects the joint from stresses to the side of the knee. Round, cordlike ligament attaching from lateral femoral condyle to fibular head It protects the joint from stresses to side of the knee. Lippert, p288

17 Supporting Structures: MCL & LCL

18 Supporting Structures Posterior Capsule: Prevents hyperextension of the knee Mansfield, p282

19 Lippert, p288 Supporting Structures Medial and lateral menisci Two half-moon, wedge-shaped fibrocartilage disks Located on the superior surface of the tibia Designed to absorb shock Thicker laterally than medially Proximal surfaces are concave, deepening the relatively flat joint surface of the tibia

20 Knee Structure Popliteal Space Area behind the knee containing important nerves (tibial and common peroneal) and blood vessels (popliteal artery and vein) Diamond shaped fossa Bound superiorly by semitendinosus and semimembranosus on the medial side and biceps femoris on lateral side. Bound inferiorly by the medial and lateral heads of the gastrocnemius Lippert, p288

21 Area Muscles of the Knee Mono-articular Muscle Myology Bi-articular Buslce Anterior Vastus Lateralis Rectus Femoris Posterior Medial Vastus Medialis Vastus Intermedialis Biceps femoris (short) Popliteus Biceps femoris (long) Semimembranosus Semitendinosus Gastrocnemius Sartorius Gracilis Lateral Tensor Fascia Latae Lippert, p290

22 Myology of the Knee Your subtopic goes here Rectus Femoris Origin Insertion Innervation Femoral n. Action Anterior-inferior iliac spine Tibial tuberosity via the quadriceps tendon Hip flexion, knee extension tidbit One of the heads of the quads Lippert, p291

23 Myology of the Knee Vastus Medialis Origin Insertion Innervation Femoral n. Action tidbit Medial lip of the linea aspera and the intertrochanterid line of the femur Tibial tuberosity via the patellar tendon Knee extension One of the heads of the quad VMO one of the first muscles of the knee to atrophy post-operatively, responsible for last o of knee extension Vastus Medialis Obliquus Lippert, p291

24 Myology of the Knee Vastus Lateralis Origin Insertion Innervation Femoral n. Action tidbit Lateral lip of the linea aspera, intertrochanteric line, lateral region of the gluteal tuberosity Tibial tuberosity via the patellar tendon Knee extension Part of the quads Lippert, p291

25 Myology of the Knee Vastus Intermedialus Origin Insertion Upper 2/3 of the anterior femoral shaft Tibial tuberosity via the patellar tendon Innervation Femoral n. Action Knee extension Lippert, p291

26 Myology of the Knee Your subtopic goes here Biceps Femoris Origin Insertion Ischial tuberosity Head of the fibula Innervation Tibial portion of the sciatic n. Action tidbit Hip extension, knee flexion One of the hamstrings Lippert, 292 A B C D Bicep F Bicep F Semimem Semiten A

27 Myology of the Knee Your subtopic goes here Semimembranosus Origin Insertion Ischial tuberosity Medial condyle of the tibia, posterior aspect Innervation Tibial portion of the sciatic n. Action tidbit Hip extension, knee flexion One of the hamstrings Lippert, p291

28 Myology of the Knee Your subtopic goes here Semitendinosus Origin Insertion Ischial tuberosity Proximal-medial surface of the tibia (pes anserinus) Innervation Tibial portion of the sciatic n. Action tidbit Hip extension, knee flexion, One of the hamstrings Lippert, 292

29 Myology of the Knee Popliteus Origin Insertion Innervation Tibial n. Action Posterior aspect of the lateral femoral condyle Posterior surface of the proximal tibia Initiates knee flexion Lippert, 292

30 Myology of the Knee Gastrocnemius Origin Insertion Innervation Tibial n. Action Medial head: posterior aspect of the medial femoral condyle Lateral head: posterior aspect of the lateral femoral condyle Calcaneal tuberosity via the Achilles tendon Flexion of the knee, plantar flexion, Lippert, 293

31 Myology of the Knee Your subtopic goes here Sartorius Origin Insertion ASIS Innervation Femoral n. Action tidbit Proximal-medial surface of the tibia (via the pes anserinus) Hip flexion, hip ABD, Hip ER, knee flexion Longest muscle in the body Biel, p326

32 Myology of the Knee Your subtopic goes here Gracillis Origin Insertion Innervation Obturator n. Body and inferior ramus of the pubis Proximal-medial aspect of the tibia (pes anserinus) Action Hip ADD, hip flexion, knee flexion Biel, p321

33 Myology of the Knee Tensor Fascia Latae Origin Iliac crest, posterior to ASIS Insertion Innervation Action Iliotibial tract Superior Gluteal Nerve Hip flexion, ABD, internal rotation Biel, p324

34 Myology Prime Movers of the Knee: Extension: Quadriceps group Flexion: Hamstring group Popliteus gastrocnemius Lippert, p294

35 Myology Summary of Muscle Innervation: Muscle Rectus femoris Vastus lateralis Vastus intermedialis Vastus medialis Semimembranosus Semitendinosus Biceps femoris long head Biceps femoris short head Popliteus gastrocnemius Nerve Femoral Femoral Femoral Femoral Sciatic Sciatic Sciatic Common Peroneal Tibial Tibial Lippert, p295

36 Common Knee Pathology Genu Valgum Genu Varum Genu Recurvatum Patellar Tendonitis Osgood-Schlatter Disease Patellofemoral Pain Syndrome Chondromalacia Patella Unhappy Triad

37 Genu Valgum and Varum Lippert, p294

38 Genu Recurvatum Lippert, p294

39 Osgood-Schlatter Lippert, p294

40 Chondromalacia Patella Lippert, p294

41 Unhappy Triad Lippert, p294

42 References Biel, A., (2010). Trail Guide to the Body, 4 th ed. Boulder, CO: Books of Discovery. Lippert, L.S. (2011). Clinical Kinesiology and Anatomy, 5 th ed. Philadelphia, PA: F.A. Davis. Mansfield, P.J., & Neumann, D.A. (2009). Essentials of Kinesiology for the Physical Therapist Assistant. St. Louis, MO: Mosby Elsevier.