BONES JOINTS MUSCLES OF THE LOWER LIMB

Transcription

1 BONES JOINTS MUSCLES OF THE LOWER LIMB

2 LOWER LIMB: BONES LOWER LIMB GLUTEAL REGION consists of 6 major segments: FEMORAL REGION (THIGH) KNEE REGION LEG REGION TALOCRURAL REGION (ANKLE) FOOT REGION

3 LOWER LIMB: BONES THE POSTERIOR FEMORAL REGION (THIGH) is between the gluteal fold and the knee joint. THE KNEE REGION includes: the prominences (condyles) of the distal femur and proximal tibia the head of the fibula the patella (knee cap) THE LEG REGION is between the knee and ankle joint. IN ANATOMY: THE LEG THE LOWER LIMB THE TALOCRURAL REGION (THE ANKLE) includes: the medial prominence the lateral prominence that flank the ankle. THE FOOT REGION the distal part containing: the tarsus the metatarsus the phalanges

4 LOWER LIMB: BONES THE SKELETON OF THE LOWER LIMB HIP BONE ILIUM ISCHIUM PUBIS FEMUR TIBIA AND FIBULA FOOT BONES TARSUS METATARSUS PHALANGES

5 LOWER LIMB: BONES THE PELVIC GIRDLE: attaches the free lower limb to the axial skeleton bony ring composed of the sacrum and right and left hip bones, jointed anteriorly at the pubic symphysis THE HIP BONE is formed by fusion of the: ILIUM ISCHIUM PUBIS THE HIP BONE At birth, the three bones are joined by hyaline cartilage. The bones begin to fuse between years of age.

6 LOWER LIMB: BONES RELATIONSHIP TO OTHER REGIONS there are 4 major entry and exit points between the lower limb and the abdomen, pelvis, and perineum These are: the gap between the inguinal ligament and pelvic bone, the greater sciatic foramen, the obturator canal (at the top of the obturator foramen), and the lesser sciatic foramen. THE HIP BONE: THE ILIUM Body fused to ischium and pubis, all meeting in the acetabulum (socket for articulation with femoral head) Ala of ilium (wing): weak spot of ilium! ASIS and PSIS

7 LOWER LIMB: BONES THE HIP BONE: THE ILIUM Neurovascular structures from within the pelvic girdle pass through the greater and lesser sciatic foramen to the gluteal region THE HIP BONE: THE PUBIS Body fused with other two bones Ramus fused with ischium Medially, the symphysial surface articulates with contralateral pubis by means of the pubic symphysis THE HIP BONE: THE ISCHIUM Body fused with other two bones Ramus fused with pubis The body s weight rests on the large ischial tuberosity when sitting ( sitting bone ) it provides attachment of posterior thigh muscles

8 LOWER LIMB: BONES THE OBTURATOR FORAMEN large opening in the hip bone it s bounded by: rami of the pubis and ischium is inferior to the acetabulum most of it is closed by a membrane of flat connective tissue, the obturator membrane THE ACETABULUM a cup-shaped depression where the head of the femur articulates with the pelvic girdle all three primary bones contribute to the formation of the acetabulum

9 LOWER LIMB: BONES THE FEMUR the longest and heaviest bone in the body consists of: shaft (body) and two ends THE FEMUR the proximal (superior) consists of the head, neck and two trochanters: lesser and greater THE FEMUR the head the fovea for the ligament of the head in the early life, the ligament gives passage to an artery supplying the epiphysis of the head THE FEMUR The angle of inclination is greatest at the birth and becomes more acute the adult angle is (averaging ) is less in females

10 LOWER LIMB: BONES THE FEMUR The neck common fracture site! THE FEMUR The body is slightly convex anteriorly smooth on anterior side posteriorly rough line the linea apsera, attachment for adductors of the thigh the greater trochanter - point of the hip; attachment site for several gluteal muscles THE FEMUR The distal end its major weight-bearing articulation is with the tibia, but it also articulates anteriorly with the patella (knee cap) the patella is the largest sesamoid bone in the body the medial and lateral femoral condyles articulate with menisci and tibial condyles to form the knee joint

11 LOWER LIMB: BONES THE TIBIA MEDIAL SIDE The weight-bearing bone of the leg and is therefore much larger than the fibula It takes part in the formation of the knee joint and below it forms the medial malleolus and most of the bony surface for articulation of the leg with the foot at the ankle joint THE FIBULA LATERAL SIDE Smaller than the tibia and is on the lateral side of the leg. It articulates superiorly with the inferior aspect of the lateral condyle of the proximal tibia. THE FIBULA LATERAL SIDE Does not take part in formation of the knee joint. The distal end forms the lateral malleolus of the ankle joint. THE TIBIA AND THE FIBULA tibial tuberosity - anterior soleal line - posterior head of fibula - proximal lateral malleolus - distal

12 LOWER LIMB: BONES THE BONES OF THE FOOT Tarsal bones: talus, calcaneus, cuboid, navicular and three cuneiforms Metatarsals I-V Phalanges I-V digits THE BONES OF THE FOOT THE TARSUS consists of 7 bones: talus calcaneus, cuboid navicular three cuneiforms

13 LOWER LIMB: BONES THE BONES OF THE FOOT THE TALUS the most superior bone of the foot sits on top of and is supported by the calcaneus it articulates above with the tibia and fibula to form the ankle joint projects forward to articulate with the intermediate tarsal bone (navicular) on the medial side of the foot THE BONES OF THE FOOT THE TALUS the most superior bone of the foot sits on top of and is supported by the calcaneus it articulates above with the tibia and fibula to form the ankle joint projects forward to articulate with the intermediate tarsal bone (navicular) on the medial side of the foot

14 LOWER LIMB: BONES THE BONES OF THE FOOT - THE CALCANEUS sits under and supports the talus box-shaped bone with its long axis generally oriented along the midline of the foot the calcaneal tendon (Achilles tendon) attaches to the calcaneal tuberosity THE BONES OF THE FOOT - THE NAVICULAR the intermediate tarsal bone on the medial side of the foot articulates behind with the talus and articulates in front and on the lateral side with the distal group of tarsal The navicular bone is located between head of the talus posteriorly and the three cuneiforms anteriorly

15 LOWER LIMB: BONES THE BONES OF THE FOOT THE CUBOID articulates posteriorly with the calcaneus medially with the lateral cuneiform anteriorly with the bases of the lateral two metatarsals THE BONES OF THE FOOT - THE 3 CUNEIFORMS the lateral, intermediate and medial cuneiform bones articulate posteriorly with the navicular bone anteriorly with the bases of the medial three metatarsals articulating with each others THE BONES OF THE FOOT Tarsal bones: talus, calcaneus, cuboid, navicular and three cuneiforms Metatarsals I-V Phalanges I-V digits (the 1-st digit has only two phalanges)

16 THE JOINTS LOWER LIMB: JOINTS OF THE LOWER LIMB HIP JOINT KNEE JOINT TIBIOFIBULAR JOINTS ANKLE JOINT (talocrural articulation) FOOT JOINTS

17 LOWER LIMB: JOINTS THE HIP JOINT multiaxial ball and socket type of synovial joint articulation between the head of the femur and the acetabulum of the pelvic bone THE HIP JOINT The articular surfaces of the hip joint are: the spherical head of the femur and the lunate surface of the acetabulum of the pelvic bone THE HIP JOINT Movements at the joint include: flexion, extension abduction, adduction (and abduction of pelvis) internal and external rotation and circumduction THE HIP JOINT The acetabulum: almost encompasses the head of the femur contributes substantially to joint stability The lunate surface is covered by hyaline cartilage The lunate surface of the acetabulum is created by the acetabular notch and fossa

18 LOWER LIMB: JOINTS THE HIP JOINT Except for the fovea, the head of the femur is also covered by hyaline cartilage. THE HIP JOINT The labrum bridges across the acetabular notch as the transverse acetabular ligament and converts the notch into a foramen. THE HIP JOINT The ligament of the head of the femur is a flat band of connective tissue that attaches: at one end to the fovea on the head of the femur and at the other end to: the acetabular fossa, transverse acetabular ligament, and margins of the acetabular notch

19 LOWER LIMB: JOINTS THE HIP JOINT The ligament of the head of the femur carries a small branch of the obturator artery (the acetabular branch), which contributes to the blood supply of the head of the femur (the artery to the head of the femur). THE HIP JOINT Three ligaments reinforce the external surface of the fibrous membrane and stabilize the joint: the iliofemoral, the pubofemoral, the ischiofemoral ligaments THE HIP JOINT CLINICAL NOTE Fractures (through the neck of the femur) are more common than hip dislocations. THE HIP JOINT CLINICAL NOTE Because the branches are often compromised in a fractured hip (common in elderly women due to osteoporosis), the femoral head commonly undergoes avascular necrosis. In cases of avascular necrosis, the femoral head is removed and a prosthetic hip joint is surgically implanted.

20 LOWER LIMB: JOINTS The hip joint is supported by the following ligaments: The largest ligament, which reinforces the hip joint anteriorly is the iliofemoral ligament (Y-shaped) The ligament which reinforces the hip joint inferiorly is the pubofemoral ligament. The thinnest ligament, which reinforces the hip joint posteriorly is the Ischiofemoral ligament. The ligament which plays only a minor role in stability but carries the artery to the head of the femur the ligamentum (teres) of the head of the femur.

21 LOWER LIMB: JOINTS THE KNEE JOINT the knee joint is the largest and most superficial joint in the body. it is a hinge type od synovial joint. The knee joint consists of: the articulation between the femur and tibia, and the articulation between the patella and the femur Two fibrocartilaginous menisci, one on each side, between the femoral condyles and tibia accommodate changes in the shape of the articular surfaces during joint movements. The medial meniscus is attached around its margin to the capsule of the joint and to the tibial collateral ligament, whereas the lateral meniscus is unattached to the capsule. Therefore, the lateral meniscus is more mobile than the medial meniscus.

22 LOWER LIMB: JOINTS THE KNEE JOINT THE SYNOVIAL MEMBRANE The synovial membrane of the knee joint attaches to: the margins of the articular surfaces and to the superior and inferior outer margins of the menisci The major ligaments associated with the knee joint are: the patellar ligament the tibial (medial) TCL and fibular (lateral) FCL collateral ligaments the anterolateral ligament ALL the anterior and posterior cruciate ligaments The patellar ligament is basically the continuation of the quadriceps femoris tendon inferior to the patella. It is attached above to the margins and apex of the patella and below to the tibial tuberosity.

23 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS The fibular collateral ligament (FCL) (lateral collateral ligament) is attached superiorly to the lateral femoral epicondyle. Inferiorly, it is attached to a depression on the lateral surface of the fibular head. The anterolateral ligament (ALL) is a ligament on the lateral aspect of the knee, anterior to the fibular collateral ligament NEW KNEE LIGAMENT! The tibial collateral ligament (TCL) (medial collateral ligament) is attached superiorly to the medial femoral epicondyle and descends anteriorly to attach to the medial margin and medial surface of the tibia.

24 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS The two cruciate ligaments: (ACL) anterior cruciate ligament and (PCL) posterior cruciate ligament The cruciate ligaments lie inside the knee joint, but outside the articular cavity.

25 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS ACL - the anterior cruciate ligament the weaker of the two cruciate ligaments arises from the anterior intercondylar area of the tibia ACL extends: superiorly, posteriorly and laterally to posterior part of the medial side of the lateral condyle of the femur ACL - the anterior cruciate ligament ACL limits posterior rolling of the femoral condyles during flexion ACL prevents posterior displacement of the femur on the tibia ACL prevents hyperextension of the knee joint ACL - the anterior cruciate ligament ACL taut during extension ACL is lax during flexion ACL MAY BE TORN WHEN THE KNEE IS HYPEREXTENDED

26 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS PCL - the posterior cruciate ligament the stronger of the two cruciate ligaments arises from the posterior intercondylar area of the tibia PCL extends: superiorly, anteriorly on the medial side of ACL to attach to the anterior part of the lateral side of the medial condyle of the femur PCL - the posterior cruciate ligament PCL taut during flexion PCL is lax during extension PCL - the posterior cruciate ligament PCL prevents backward sliding of the tibia on the femur PCL limits hyperflexion of the knee joint

27 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS THE EXTRACAPSULAR LIGAMENTS OF KNEE JOINT: The joint capsule is strengthened by five extracapsular or capsular (intrinsic) ligaments: patellar ligament fibular collateral ligament tibial collateral ligament oblique popliteal ligament, and arcuate popliteal ligament THE INTRA-ARTICULAR LIGAMENTS OF KNEE JOINT: The intra-articular ligaments within the knee joint consist of the cruciate ligaments and menisci: anterior cruciate ligament (ACL) posterior cruciate ligament (PCL) coronary ligaments transverse ligament of the knee posterior meniscofemoral ligament

28 LOWER LIMB: JOINTS THE KNEE JOINT THE LIGAMENTS PCL - the posterior cruciate ligament PCL is taut during flexion PCL lax during extension 50% of the classical cause of isolated PCL injury is the DASHBOARD INJURY PCL MAY BE TORN WHEN THE KNEE IS HYPERFLEXTED

29 LOWER LIMB: JOINTS THE TIBIOFIBULAR JOINT The small proximal tibiofibular joint is synovial in type and allows very little movement. The interosseous membrane of leg is a tough fibrous sheet of connective tissue that spans the distance between facing interosseous borders of the tibial and fibular shafts. The membrane provides an increased surface area for muscle attachment. The inferior tibiofibular syndesmosis is a compound fibrous joint type and allows very slight movement.

30 LOWER LIMB: JOINTS THE ANKLE JOINT The ankle joint (talocrural articulation) is synovial in type and involves the talus of the foot and the tibia and fibula of the leg The fibula and tibia create a socket for the upper expanded part of the body of the talus: the roof of the socket is formed by the inferior surface of the distal end of the tibia the medial side of the socket is formed by the medial malleolus of the tibia the longer lateral side of the socket is formed by the lateral malleolus of the fibula The articular surfaces are covered by hyaline cartilage The ankle joint is stabilized by: the medial (deltoid) ligaments and the lateral ligaments

31 LOWER LIMB: JOINTS THE ANKLE JOINT THE MEDIAL LIGAMENT THE DELTOID LIGAMENT MEDIAL LIGAMENT (DELTOID LIGAMENT) The medial (deltoid) ligament is large, strong and triangular shape. The medial ligament is subdivided into four parts based on the inferior points of attachment: tibionavicular part tibiocalcaneal part posterior tibiotalar part anterior tibiotalar part THE ANKLE JOINT THE LATERAL LIGAMENT The lateral ligament of the ankle is composed of three separate ligaments: the anterior talofibular ligament the posterior talofibular ligament, and the calcaneofibular ligament

32 LOWER LIMB: JOINTS THE FOOT JOINTS THE INTERTARSAL JOINTS The numerous synovial joints between the individual tarsal bones mainly invert, evert, supinate, and pronate the foot. The major joints include: the subtalar, the talocalcaneonavicular, the calcaneocuboid joints THE SUBTALAR JOINT The subtalar joint is between: the large posterior calcaneal facet on the inferior surface of the talus, and the corresponding posterior talar facet on the superior surface of the calcaneus. THE SUBTALAR JOINT The anatomical subtalar joint is a single synovial joint between the slightly concave posterior calcaneal articular surface of the talus and the convex posterior articular facet of the calcaneus. Orthopaedic surgeons use the term subtalar joint for the compound functional joint consisting of the anatomical subtalar joint plus the talocalcaneal part of the talocalcaneonavicular joint.

33 LOWER LIMB: JOINTS THE FOOT JOINTS The transverse tarsal joint is a compound joint formed by two separate joints aligned transversely: the talonavicular part of the talocalcaneonavicular joint and the calcaneocuboid joint. THE TALOCALCANEONAVICULAR JOINT It is a complex joint in which the head of the talus articulates with: the calcaneus plantar calcaneonavicular ligament below, and the navicular in front THE CALCANEOCUBOID JOINT It is a synovial joint between: the facet on the anterior surface of the calcaneus, and the corresponding facet on the posterior surface of the cuboid. THE TARSOMETATARSAL JOINTS are between the metatarsal bones and tarsal bones. There are plane joints and allow limited sliding movements.

34 LOWER LIMB: JOINTS THE FOOT JOINTS THE METATARSOPHALANGEAL JOINTS are ellipsoid synovial joints between the sphere-shaped heads of the metatarsals and the corresponding bases of the proximal phalanges of the digits. THE INTERPHALANGEAL JOINTS The interphalangeal joints are hinge joints that allow mainly flexion and extension. They are reinforced by medial and lateral collateral ligaments and by plantar ligaments

35 LOWER LIMB: TIGH MUSCLES THE TIGH MUSCLES THE ANTERIOR TIGH MUSCLES pectineus iliopsoas sartorius quadriceps femoris THE ADDUCTOR (MEDIAL) THIGH MUSCLES the adductor longus adductor brevis adductor magnus gracilis obturator externus THE POSTERIOR THIGH MUSCLES The hamstring muscles are: semitendinosus semimembranosus biceps femoris (long head)

36 LOWER LIMB: TIGH MUSCLES THE PECTINEUS MUSCLE The pectineus is a flat quadrangular muscle located in the anterior part of the superomedial aspect of the thigh. The pectineus is innervated by two different nerves: femoral nerve (L2, L3); may receive a branch from obturator nerve. THE ILIOPSOAS MUSCLE The iliopsoas is the chief flexor of the thigh, the most powerful of the hip flexors with the longest range. Its mass located in the posterior wall of the abdomen and greater pelvis. Its broad lateral part, the iliacus, and its long medial part, the psoas major. FLEXOR OF THE HIP JOINT

37 LOWER LIMB: TIGH MUSCLES THE SARTORIUS MUSCLE the tailor s muscle is long and ribbon-like the longest muscle in the body It descends inferiorly as far as the medial side of the knee None of the actions of the sartorius is strong THE QUADRICEPS FEMORIS MUSCLE It covers almost all the anterior aspect and sides of the femur Consists of 4 parts: rectus femoris vastus lateralis vastus intermedius vastus medialis The quadriceps is the great extensor of the leg FLEXOR OF THE HIP JOINT

38 LOWER LIMB: TIGH MUSCLES THE QUADRICEPS FEMORIS MUSCLE The quadriceps is the great extensor of the leg Extends the knee against gravity The tendons of the four parts of the quadriceps unite in the distal portion of the thigh to form a single, strong, broad quadriceps tendon. The patellar ligament, attached to the tibial tuberosity, is the continuation of the quadriceps tendon EXTENSOR OF KNEE THE PECTINEUS: Femoral nerve (L2, L3); may receive a branch from obturator nerve THE PSOAS MAJOR: anterior rami of lumbar nerves (L1, L2, L3) THE ILIACUS: femoral nerve (L2, L3) THE SARTORIUS: femoral nerve (L2, L3) THE QUADRICEPS FEMORIS: femoral nerve (L2, L3, L4)

39 LOWER LIMB: TIGH MUSCLES THE MUSCLES OF THE MEDIAL COMPARTMENT THE ADDUCTOR GROUP OF MUSCLES consisting of the adductor longus adductor brevis adductor magnus gracilis obturator externus All five muscles cross the hip joint, but only gracilis reaches beyond the knee. They attach proximally to the anteroinferior external surface of the pelvis and adjacent obturator membrane, and distally to the linea aspera of the femur. Most of the adductor muscles are supplied by the obturator nerve

40 LOWER LIMB: TIGH MUSCLES THE ADDUCTOR LONGUS The adductor longus is a large, fan-shaped muscle and is the most anteriorly placed of the adductor group THE ADDUCTOR BREVIS The adductor brevis, the short adductor, lies deep to the pectineus and adductor longus THE ADDUCTOR MAGNUS The adductor magnus is the largest, most powerful, and most posterior muscle in the adductor group THE ADDUCTOR HIATUS

41 LOWER LIMB: TIGH MUSCLES THE GRACILIS It is the only one of the group to cross the knee joint as well as the hip joint. Gracilis is sometimes transplanted to replace damaged muscles elsewhere in the body. THE OBTURATOR EXTERNUS The obturator externus is a flat, relatively small muscle that is deeply placed in the superomedial part of the thigh. All adductor muscles, except the hamstring part of the adductor magnus and part of the pectineus are supplied by the obturator nerve (L2 L4). The hamstring part of the adductor magnus is supplied by the tibial part of the sciatic nerve (L4). The gracilis, sartorius and semitendinosus muscles have a common tendinous insertion, the pes anserinus, into the superior part of the medial surface of the tibia. THE ADDUCTOR MAGNUS: Adductor part: obturator nerve (L2, L3, L4), branches of posterior division. Hamstring part: tibial part of sciatic nerve (L4). THE ADDUCTOR LONGUS THE ADDUCTOR BREVIS OBTURATOR NERVE THE GRACILIS THE OBTURATOR EXTERNUS

42 LOWER LIMB: TIGH MUSCLES THE POSTERIOR TIGH MUSCLES The hamstring muscles are: semitendinosus semimembranosus biceps femoris (long head)

43 LOWER LIMB: TIGH MUSCLES THE POSTERIOR TIGH MUSCLES The hamstring muscles ( hamstrings for short) share common features: Proximal attachment to the ischial tuberosity deep to the gluteus maximus Distal attachment to the bones of the leg Thus they span and act on two joints, producing extension at the hip joint and flexion at the knee joint Innervation by the tibial division of the sciatic nerve. THE SEMITENDINOSUS AND SEMIMEMBRANOSUS: Tibial division of sciatic nerve part of tibia THE BICEPS FEMORIS Long head: tibial division of sciatic nerve Short head: common fibular division of sciatic nerve Distally, the tendon attaches to the medial surface of the superior part of the tibia as part of the pes anserinus formation in conjunction with the tendinous insertions of the sartorius and gracilis.