Lower Limb Anatomy 2024 PDF

BMS10103: ANATOMY FOR HEALTH PROFESSIONAL MSK: LOWER LIMB Dr. Norhazilah Muhamad Department of Anatomy & Physiology Faculty of Medicine Strictly for educational purposes only LEARNING OUTCOMES Name the pelvis and bones of lower limb. State the mus...

BMS10103: ANATOMY FOR HEALTH PROFESSIONAL MSK: LOWER LIMB Dr. Norhazilah Muhamad Department of Anatomy & Physiology Faculty of Medicine Strictly for educational purposes only LEARNING OUTCOMES Name the pelvis and bones of lower limb. State the muscles, blood supply and innervation of the gluteal region and lower limbs. Describe the hip and knee joints of lower limb. 2  GLUTEAL REGION Posterolateral region between the iliac crest and the gluteal fold. Made up of gluteal muscles and a thick layer of superficial fascia. BOUNDARIES:  SUP  iliac crest (L4)  MED  intergluteal cleft  LAT  greater trochanter of femur  INF  gluteal fold  PELVIS A basin-shaped complex of bones that connects the trunk and the legs. It supports and balances the trunk. It contains and supports the intestines, urinary bladder and the internal sex organs. Consists of sacrum, coccyx and hip bones. 4 PELVIS: Bones 5  HIP BONE Iliac crest Iliac tuberosity ASIS Iliac fossa PSIS AIIS PIIS Greater Greater sciatic Pubic sciatic notch notch tubercle Lesser ischial sciatic spine notch ischial Obturator tuberosity foramen 6 SACRUM & COCCYX 7  MUSCLES OF GLUTEAL REGION Gluteus minimus Gluteus medius Gluteus maximus  Superficial group  Deep group large muscles small muscles abductors and extenders lateral rotators  SUPERFICIAL GLUTEAL MUSCLES Act to abduct and extend the lower limb at the hip joint.  Gluteus Gluteus Gluteus maximus medius minimus Largest gluteal Fan-shaped lie Deepest & muscle between the smallest gluteus maximus Fan-shaped Quadrangular- shape and minimus. NS: INF gluteal nerve NS: SUP gluteal nerve Extends the hip joint Adduct the hip joint  Tensor fascia lata The most anterior of superficial group. Attachments: Origin: Ilium Insertion: iliotibial tract Innervation: Superior gluteal nerve Action: Abducts hip joint Stabilizes knee in extension (assists gluteus maximus) *supportive role in the gait cycle  DEEP GLUTEAL MUSCLES Smaller muscles, located underneath the gluteus minimus. Mainly lateral rotators of the thigh at hip joint. (all inserted at greater trochanter of femur) Also abduct thigh (except quadratus femoris). They also stabilize the hip joint by fixed the femoral head in the acetabulum.  PIRIFORMIS Important landmark because it divides the greater sciatic foramen into suprapiriform & infrapiriform foramina. Structures that pass through superior to piriformis:  Superior gluteal artery & nerve Structures that pass through the greater sciatic foramen inferior to piriformis: PIN & PINS  Posterior cutaneous nerve of thigh  Inferior gluteal vessels & nerve  Nerve to quadratus femoris  Pudendal nerve  Internal pudendal vessels  Nerve to obturator internus  Sciatic nerve 13 MAIN ACTION OF DEEP GLUTEAL MUSCLES EXTERNAL HIP ROTATORS Greater trochanter  MUSCLES OF GLUTEAL REGION Muscle Nerve Action Superficial Gluteus maximus Inferior gluteal Extensor hip joint Gluteus medius Gluteus minimus Superior gluteal Abductor hip Tensor fascia lata joint Deep Piriformis Nerve to piriformis Obturator internus Nerve to obturator Lateral Superior gemellus internus rotators of Inferior gemellus Nerve to quadratus femur Quadratus femoris femoris GLUTEAL REGION- Arteries & Nerve 16  ARTERIES OF GLUTEAL REGION GLUTEAL ARTERIES – SUPERIOR & INFERIOR Origin: Internal iliac artery Enter the gluteal region from the pelvic cavity through the greater sciatic foramen. Include:  Superior gluteal  Inferior gluteal  ARTERIES OF GLUTEAL REGION SUPERIOR GLUTEAL ARTERY  Origin: Anterior trunk of internal iliac artery  Supplies muscles of the posterior pelvic region. INFERIOR GLUTEAL ARTERY Origin: Posterior trunk of internal iliac artery Supplies gluteal region and posterior of thigh. Have important collateral anastomoses with branches of the femoral artery  TROCHANTERIC ANASTOMOSIS  A network between the superior gluteal artery and medial/lateral circumflex femoral arteries  Function: Provides the collateral blood flow to support the femoral head.  NERVES OF GLUTEAL REGION Nerves enter gluteal region: Superior gluteal nerve Inferior gluteal nerve Nerve to obturator internus Nerve to quadratus femoris Nerve to piriformis Pudendal nerve Sciatic nerve Posterior cutaneous *All nerves are branches of the sacral nerve of thigh plexus & enter the gluteal through the greater sciatic foramen  SACRAL PLEXUS Formed by L4 to S3 nerves (root values / nerve roots). Branches: Gluteal region Superior gluteal nerves Inferior gluteal nerves Nerve to obturator internus Nerve to quadratus femoris Nerve to piriformis  Perineum  Pudendal nerve  Thigh  Sciatic nerve  Posterior cutaneous nerve of thigh LOWER LIMB  THIGH REGION BOUNDARIES: Posteriorly: between gluteal fold and the knee Anteriorly: between the inguinal ligament and the knee joint Knee joint  BONE OF THIGH: FEMUR Longest & strongest bone. Important for weight-bearing, movement & muscle attachment.  Compartments of the thigh  Divided into 3 compartments:  Anterior  Medial  Posterior  Organised by:  Fascia lata (deep fascia that invests the thigh)  Fascial intermuscular septae  ANTERIOR THIGH MUSCLES  Include: Illiopsoas  Sartorius Pectineus  Quadriceps femoris Vastus lateralis Rectus femoris Sartorius Vastus medialis Rectus femoris Vastus Vastus medialis intermedius Vastus lateralis  Illiopsoas  Pectineus iliacus psoas major  ANTERIOR THIGH MUSCLES Blood supply: Femoral vessels Nerve: Femoral nerve (L2 – L4) Action: extensor of knee joint 27  SARTORIUS  The longest muscle in the body.  Long and thin muscle, running across the thigh in a inferomedial direction.  Innervation: Femoral nerve  Action: Flexes, abducts and laterally rotate thigh at hip joint Flexes leg at the knee joint Cross legged sitting  QUADRICEPS FEMORIS  Composed of 4 heads of muscles which fuse together forming quadriceps femoris tendon.  Attachments: Origin: linea aspera of femur (VL & VM) shaft of femur (VI) AIIS (Rectus femoris) Insertion: into tibial tuberosity via patellar tendon  QUADRICEPS FEMORIS  All muscles cross knee joint but only rectus femoris crosses both hip & knee joints.  Innervation: Femoral nerve  Action: Flexes the thigh at the hip joint (Rectus femoris only) Chief extensor of knee joint 30  ILLIOPSOAS  Include: *Psoas minor is absent in almost 40% of subjects  Psoas major and minor  Iliacus  Innervation:  Femoral nerve - iliacus  Lumbar plexus (L1-L3) - psoas  Action: Chief flexor of the thigh  PECTINEUS  Flat muscle that forms the base of the femoral triangle.  Attachments: Origin – pectineal line Insertion – medial lip of linea aspera  Innervation: Femoral nerve * branch from the obturator nerve.  Action: Flexes and adducts* thigh at hip joint * transitional muscle of anterior & medial compartment  Anterior Compartment of the Thigh Muscle Nerve Action Psoas major Lumbar plexus Flexor of femur Iliacus Sartorius * Cross legged sitting Pectineus Quadriceps femoris: Vastus lateralis Femoral nerve Extensor of knee joint Vastus intermedius (L2, 3, 4) Vastus medialis Rectus femoris *  MEDIAL THIGH MUSCLES  Main action is to adduct the thigh at the hip joint.  Comprise of 5 muscles:  Gracilis  Adductor longus  Adductor brevis  Adductor magnus  Obturator externus  All muscles: cross the hip joint Origin – pubis (except hamstring part of adductor magnus & obturator externus) *only gracilis reaches beyond the knee  MEDIAL THIGH MUSCLES  Blood supply: Obturator artery  Nerve: Obturator nerve (L2 –L4)  Main action: Hip adductors  GRACILIS  The most superficial medial thigh muscles.  Descends vertically in medial side of thigh.  Innervation: Obturator nerve  Actions:  Adducts thigh at hip joint  Flexes leg at knee joint  ADDUCTOR LONGUS ADDUCTOR BREVIS  Short muscle, lying  A large and flat underneath the adductor muscle. longus.  Forms the medial  Lies in between the border of the femoral anterior and posterior triangle. divisions of the obturator nerve.  ADDUCTOR MAGNUS The largest & deepest medial thigh muscles Triangular in shape Consists of 2 parts: Adductor part Hamstring part * the 2 parts differ in their attachments, nerve supplies & main actions  ADDUCTOR MAGNUS Adductor part Origin: ischiopubic ramus Insertion: linea aspera of femur Nerve: Obturator nerve Action: adduction & flexes thigh Hamstring part Origin : ischial tuberosity Insertion: adductor tubercle of femur Nerve: tibial part of sciatic nerve Action: adduction & extends thigh  OBTURATOR EXTERNUS Flat, fan-shaped. Deeply placed in superior part of thigh. Attachments: Origin: obturator membrane Insertion: trochanteric fossa of femur  Action: laterally rotates thigh at hip joint *collectively adducts thigh with other medial thigh muscles  POSTERIOR THIGH MUSCLES Consist of: Biceps femoris (BF)*  Semitendinosus (ST)  Semimembranosus (SM) Collectively known as hamstrings (BF long head, ST & SM).  As group, these muscles act to extend at the hip, and flex at the knee.  HAMSTRINGS  The word ham originally referred to the fat and muscle behind the knee.  String refers to tendons  Thus, the hamstrings are the string-like tendons felt on either side of the back of the knee.  HAMSTRINGS Shares common features (tie): Innervation: tibial division of sciatic nerve Origin: ischial tuberosity Action as a group: extend thigh & flex leg (2 joints involved) BF short head: common fibular division of sciatic nerve  BONES OF THE LEG: TIBIA & FIBULA Tibial tuberosity *palpable approximately 5 cm inferior to the apex of the patella lateral malleolus  FASCIAL COMPARTMENTS OF THE LEG Divided into anterior, posterior and lateral compartments by:  Interosseous membrane  Bones  Anterior & posterior intermuscular septa Muscles in each compartment share common functions & innervations. LEG: COMPARTMENTS & MUSCLES  LEG: MAIN ACTIONS Compartment On the foot On the toes Anterior Dorsiflex Extend Posterior Plantarflex Flex Anterior & Invert posterior Lateral Evert  LEG: ANTERIOR COMPARTMENT  Located: anterior to interosseous membrane. Bounded anteriorly by deep fascia. Most susceptible to compartment syndrome.  ANTERIOR LEG MUSCLES  Dorsiflexor (extensor) compartment  Consists of: Tibialis anterior (TA) Extensor hallucis longus (EHL) Extensor digitorum longus (EDL) Fibularis tertius (FT)  Rule of thumb: All muscles pass & insert anterior to the ankle joint – dorsiflexors of ankle joint The long extensors also attach to the dorsal aspect of digits – extensors of toes ANTERIOR LEG MUSCLES  RETINACULA OF ANKLE  Are thickenings of the deep fascia on the medial side of the ankle  Keep the long tendons around the ankle joint in position  Act as pulley. Include: SUP extensor retinaculum  INF extensor retinaculum  Flexor retinaculum SUP peroneal retinaculum  INF peroneal retinaculum  EXTENSOR RETINACULA OF ANKLE SUPERIOR  strong, broad band of deep fascia  attached to the distal ends of the ANT borders of fibula & tibia. INFERIOR  a Y-shaped band attaches laterally to the anterosuperior surface of the calcaneus.  bind the tendons of the anterior compartment muscles  EXTENSOR RETINACULA OF ANKLE  Structures that pass ANT to the extensor retinacula (MED to LAT): Saphenous nerve Great saphenous vein Superficial peroneal nerves  Structures that pass deep to the extensor retinacula (MED to LAT): Tendon of tibialis anterior EHL ANT tibial vessels ANT tibial nerve EDL PT  ANTERIOR LEG MUSCLES Muscle Description & attachment Tibialis anterior Lies lateral to tibia (TA) Inserted to medial part of foot TA Extensor Inserted to distal phalanx hallucis longus of great toe (EHL) EDL Extensor Inserted to lateral 4 toes EHL digitorum phalanges longus (EDL) FT Fibularis tertius Separated part of EDL (FT) Inserted to base of 5 th (not always metatarsal present)  ANTERIOR LEG MUSCLES Action other than Nerve & Muscle dorsiflexion artery TA Inversion of foot (strongest Deep Support medial arch dorsiflexors) fibular of foot nerve EHL Extension of great toe EDL Anterior Extension of lateral 4 tibial toes artery FT Aids in eversion of (weakest foot dorsiflexors) Clinical aspect: Lesion of Deep fibular nerve results in footdrop (inability to dorsiflex)  LATERAL LEG MUSCLES Common features: Evertors of the foot Innervation: Superficial peroneal nerve Comprises of:  Fibularis (peroneus) longus (FL)  Fibularis (peroneus) brevis (FB) Help maintain the stability of ankle joint.  PERONEAL RETINACULA OF ANKLE SUPERIOR  connects the lateral malleolus to the LAT surface of calcaneum.  binds the tendons of PL & PB to the back of the LAT malleolus. INFERIOR  binds the tendons of PL & PB to the LAT side of the calcaneum.  LATERAL LEG MUSCLES Muscle Description Nerve supply Action Fibularis Attachment: Eversion of longus head of foot (FL) fibula to 1 st Longer & metatarsal & Plantarflexion more cuneiform of foot superficial bone Supports FL Superficial arches of (tendon can be palpated at foot lateral fibular malleolus) n. FB Fibularis Fusiform Eversion of brevis muscle foot (FB) lies deep to FL Inserted to 5th metatarsal  POSTERIOR LEG MUSCLES SUPERFICIAL DEEP *separated by transverse intermuscular septum  POSTERIOR LEG MUSCLES Common features:  Strong plantar flexors of the foot at the ankle joint  Supplied by tibial nerve  Associated with erect posture & bipedal locomotion  Play important role in circulation *contractions of these muscles help in the venous return from the lower limb * Soleus is called as the “peripheral heart” presence of large valveless veins in its substance. when the muscle contracts, the blood from these veins are pump out.  POSTERIOR LEG MUSCLES: SUPERFICIAL GROUP PLANTARIS GASTROCNEMIUS SOLEUS  POSTERIOR LEG MUSCLES: SUPERFICIAL GROUP Muscle Innervation Action Gastrocnemius (Also flexes the knee) Strong Tibial plantarflexors Plantaris nerve Soleus Soleus Plantaris Weak plantarflexors Achilles (calcaneal) tendon  All 3 muscles in superficial group of posterior compartment inserted into the calcaneal bone (via achilles tendon).  *the most superficial muscle in POST leg *Thickest & strongest tendon of the body  PLANTARIS SOLEUS  A small fusiform muscle with a long slender tendon.  Lies between the gastrocnemius & soleus.  A vestigial muscle in man.  Sometimes it is  Sole-shaped, absent. shaped like a fish “soleus”.  Lies deep to the gastrocnemius. TRICEPS SURAE  DEF: 3-headed muscles in POST compartment of leg. 2 heads of gastrocnemius + soleus  Main action: Plantarflexo rs  POSTERIOR LEG MUSCLES: DEEP GROUP  Popliteus  Flexor digitorum longus  Flexor hallucis longus  Tibialis posterior  FLEXOR RETINACULA OF ANKLE  Extends from the MED malleolus downward & backward to be attached to the MED surface of the calcaneum.  Binds the tendons of the deep muscles of the back of the leg to the back of the MED malleolus as they pass forward to enter the sole of the foot.  FLEXOR RETINACULA OF ANKLE Structures passing deep to the retinaculum (MED to LAT): 1. Tibialis posterior tendon 2. Flexor digitorum longus tendon 3. Posterior tibial artery (with venae commitantes) 4. Tibial nerve 5. Flexor hallucis longus Tom did a very nice hat  POSTERIOR LEG MUSCLES: DEEP GROUP Muscle Innervation Actions Popliteus Unlocks knee joint Popliteus Tibialis Inversion of foot posterior Plantarflexion of (TP) foot TP Tibial Support medial nerve arch of foot FHL Flexor hallucis Flexes great toe FDL longus (FHL) Flexor digitorum Flexes lateral 4 toes longus (FDL)  RIGHT LEG Extensor ANTERIOR dig. longus Peroneus tertius Extensor hall. longus DORSI FLEXORS Peroneus longus Deep Peroneal N Tibialis Ant Anterior Tibial Artery Superficial Peroneal N INVERTORS FDL Peroneal Artery FHL LATERAL TP EVERTORS PO Gastrocnemius P Peroneus PLANTAR FLEXORS brevis Soleus Posterior Tibial Artery Tibial N Plantaris POSTERIOR  FOOT Sole (plantar) of the foot  Region contacting the ground.  Skin thick & hairless numerous sweat glands sensory nerve supply: o Medial branch of tibial nerve  medial side of heel o Medial plantar nerve  MED 2/3 of the sole o Lateral plantar nerve  LAT 1/3 of the sole  FOOT Dorsum of the foot  Skin thin, hairy & freely mobile on the underlying tendons & bones. Sensory nerve supply: o Superficial peroneal nerve, deep peroneal, saphenous & sural nerves.  BONES OF THE FOOT TARSALS METATARSALS PHALANGES  MUSCLES OF THE FOOT  Functions: support phase of stance maintaining arches of foot *basically resist force that tend to reduce the longitudinal arch as weight is received at the heel & transferred to the ball of foot Intrinsic muscles: originate and insert in the foot  MUSCLES OF THE FOOT  There is only 1 intrinsic muscle on dorsal aspect of the foot: extensor digitorum brevis (EDB)  All other intrinsic muscles are on the plantar side of the foot.  Plantar (sole) muscles: Arranged in 4 layers (in 4 compartments)  PLANTAR APONEUROSIS  Triangular thickening of deep fascia in the sole of the foot.  Attachments: POST  Medial tubercle of calcaneus. ANT  divided into 5 slips which pass to the 5 toes. LAT  attached to metatarsals by medial & lateral intermuscular septa.  Functions: Protects the underlying neurovascular structures. Maintain longitudinal arches of the foot. MUSCLES OF THE SOLE: 1st layer Muscle Innervation Action Abductor Abduct Hallucis great (AbH) Medial toe Flexor plantar n. Flexes digitorum lateral brevis 4 toes (FDB) Abductor Lateral Abducts digiti plantar n. little minimi toe (AbD)  MUSCLES OF THE SOLE: 2nd layer (flexors) Muscle Innervation Action Lumbricals 1 st lumbrical: - Flexion medial plantar of MPJ n. -Extension of IPJ 2 nd , 3 rd , 4 th lumbricals: lateral plantar n. Quadratus Flexes plantae Lateral plantar toes (by (QP) n. assisting FDL) MPJ = Metatarsophalangeal joint IPJ = interphalangeal joint FDL = flexor digitorum longus  MUSCLES OF THE SOLE: 3rd layer Muscle Innervation Action Flexor Medial Flexion of hallucis plantar n. great toe brevis (FHB) Adductor Adducts hallucis great toe (AdH) Lateral Flexor plantar n. Flexe digiti s little minimi toe brevis (FDB)  All actions occur at MPJ  MUSCLES OF THE SOLE: 4th layer Muscle Innervation Action Plantar Adduction interossei of toes (PAD) Lateral plantar n. Dorsal Abduction interossei of toes (DAB)  All actions occur at MPJ  MUSCLES OF SOLE THE FOOT  Arranged in four layers from the inferior layer superiorly Layer 1 Abd H * Abd DM FDB * Layer 2 Quadratus Lumbricals * Tendon Tendon plantae FHL FDL Layer 3 FHB * FDM ADH Layer 4 Dorsal Plantar Tibialis Peroneus interossei interossei posterior longus * Supplied by Medial plantar nerve  INTRINSIC MUSCLES OF DORSUM OF THE FOOT Extensor digitorum brevis  Nerve supply  Pseudoganglion of the lateral branch of deep peroneal nerve.  Action Dorsiflexes the medial 4 toes.  BLOOD SUPPLY OF THE LOWER LIMB External Femoral artery iliac artery Course: Femoral artery Continuation of external iliac artery Passes under inguinal ligament Adductor hiatus Change its name to popliteal artery once passed through adductor hiatus Clinical importance: Femoral artery is palpable just inferior to the midpoint of inguinal ligament  Anterior view of Popliteal artery thigh Popliteal artery begins at Femoral the opening of adductor artery hiatus Adductor hiatus Terminates by dividing into anterior & posterior tibial Popliteal artery artery Posterior view of leg (deep dissection)  Arteries of the leg Posterior tibial artery Terminal branch of popliteal artery Passes through posterior compartment of leg Accompanied by tibial nerve & veins Enters the foot through the tarsal tunnel on the medial side of the ankle and posterior to the medial Anterior tibial artery malleolus Originates from popliteal Terminates by diving into artery. medial & lateral plantar Supplies anterior arteries in the foot. compartment of leg.  Posterior view of Fibular artery leg Popliteal artery Branches from posterior Anterior tibial artery tibial artery Fibular artery Posterior It descends along the medial tibial artery side of fibula Supplies the lateral compartment muscles  COLLATERAL ANASTOMOSIS Include: Inferior gluteal artery/obturator artery - Internal iliac artery Medial circumflex artery Lateral circumflex Femoral artery artery Perforating artery  When external iliac artery or femoral artery are obstructed, this anastomosis supplies blood to lower limb.  Arteries of foot  Arteries of foot are the terminal branches of anterior & posterior tibial arteries. Anterior tibial a. Dorsalis pedis artery Dorsalis pedis a. Is direct continuation of the anterior tibial artery Deep plantar a. Dorsal Begins as it crosses the ankle Metatarsal a. joint Runanteromedially between the dorsal digital a. EHL & the EDL tendons  Lower limb Innervation (motor) Main action Arterial supply Gluteal Superficial Superior gluteal Abductors Superior (except Gluteal maximus) (except Gluteal gluteal a. maximus – Inferior extend) gluteal a. Deep Nerve to Lateral rotators piriformis, obturator internus & quadratus femoris Thigh Anterior Femoral Flexors Femoral a. Medial Obturator Adductors Obturator Posterior Tibial part of sciatic Extensors a. Inferior gluteal a. Leg Anterior Deep fibular Dorsiflexors Anterior tibial a. Extend the toes Posterior tibial a. Lateral Superficial fibular Evertors Fibular a. Posterior Tibial Plantarflexors Flex the toes Foot Medial or lateral plantar Dorsalis pedis nerves a. Medial plantar a. Lateral plantar a.  VENOUS DRAINAGE OF LOWER LIMB Has superficial and deep veins: superficial veins are in the subcutaneous tissue. deep veins are deep to fascia lata and accompany the arteries (similar names). Both veins are interconnected. Valves are more numerous in deep veins.  SUPERFICIAL VEINS Superficial veins of lower limb:  Great saphenous vein (largest)  Small saphenous vein   a gap in fascia lata, 4 cm inferolateral to pubic tubercle It formed by venous arch on dorsal foot. It arises on the lateral side of It ascends along medial side of the foot. lower limb to the proximal thigh. It empties into the femoral vein It empties into popliteal vein. through the saphenous opening.  NERVES OF THE LOWER LIMB FEMORAL NERVE COURSE:  Originates from lumbar plexus (L2 – L4)  Enters the femoral triangle by passing under the inguinal Femoral nerve ligament.  Supplies iliacus & pectineus.  Divides into branches:  Numerous motor nerves (ANT thigh muscles)  Anterior cutaneous branches (skin on ANT thigh & knee) Saphenous  Saphenous nerve nerve (skin on medial knee, leg & foot)  OBTURATOR NERVE COURSE:  Originates from lumbar plexus (L2-L4)  Descends in the middle part of psoas muscle and then enter the pelvis. Obturator nerve  Passing through the obturator canal to enter the medial compartment of thigh.  Supplies medial thigh muscles & medial thigh skin  SCIATIC NERVE  It is the thickest nerve in the body  COURSE: Originates from lumbosacral plexus (L4 - S3) It leaves the pelvis via the greater sciatic foramen below piriformis muscle (but did not supplies the gluteal). Then enters & supplies the posterior thigh muscles.  Divides at superior border of popliteal fossa into Tibial nerve and Common fibular nerve.  TIBIAL NERVE The larger terminal branch of sciatic nerve Begins in the lower 1/3 of the POST thigh above the apex of the popliteal fossa Sciatic nerve Root values: L4 – S3 Tibial nerve Terminal branches:  Medial plantar nerve Posterior view  Lateral plantar nerve TIBIAL NERVE COMMON FIBULAR NERVE The smaller terminal branch of sciatic nerve Sciatic It winds round the neck of fibula, pierces the CF nerve Fibularis longus, and divides into superficial and deep fibular nerves Deep fibular Posterior view n. SUPERFICIAL FIBULAR NERVE Arises from common fibular nerve at the lateral side of neck of fibula (smaller terminal branch) Descends in the lateral compartment of the leg (innervates the muscles)  DEEP FIBULAR NERVE Superficial Another terminal branch of the fibular n. common fibular nerve Pierces anterior intermuscular septum & enters the anterior Deep compartment of leg fibular n. Innervates all muscles of the anterior compartments of leg & dorsum of foot  Nerves of foot Plantar view of foot tibial nerve Posterior to medial malleolus, the FDB LP tibial nerve divides into: MP  Medial plantar nerve AH QP  Lateral plantar nerve Plantar nerves supply the intrinsic muscles of the foot proper plantar digital nerve  JOINTS OF THE LOWER LIMB Hip joint HILTON’S LAW: Knee joint A nerve supplying a joint also supplies Ankle joint the muscles moving the joint and the skin over the distal attachments of these muscles.  Hip Joint Type: synovial ball and socket type Strongest joint in the body Articulating bones: head of femur – all covered by hyaline cartilage except at fovea capitis (pit for ligament of femoral head) acetabulum of hip bone Capsule of the joint:  Formed by fibrous layer (external) & synovial membrane (internal)  Hip Joint: Ligaments Anterior part of capsule: Iliofemoral - strongest ligament in the body - prevent trunk from falling backward (hyperextension of hip joint) when standing Pubofemoral - prevent over-abduction of hip joint Posterior part of capsule: Ischiofemoral - weak compared to others  Hip Joint: Ligaments  Ligament of femoral head (Ligamentum teres) - Laterally attached to fovea capitis - Medially attached at transverse acetabular ligament & acetabular notch - Little importance in strengthening the hip joint *Transmits acetabular branch of obturator artery to the head of femur  Transverse acetabular ligament - Extend across acetabular notch - Converts acetabular notch into foramen: *Transmit acetabular vessels & nerves to the joint  Hip Joint Blood supply: medial and lateral circumflex femoral arteries ** Cruciate anastomosis Nerve supply: Femoral nerve Obturator nerve –same nerves that supply knee joint – “referred pain to the knee” Sciatic nerve Movements of Hip Joint (Diarthrosis) Flexion – Iliopsoas muscle – Sartorius – Rectus femoris – Pectineus Extension – Gluteus maximus – Gracilis Adduction – Adductors muscles – Gracilis Abduction – Gluteus medius – Gluteus minimus  Movements of Hip Joint Rotation  Lateral / External Gluteus maximus Quadratus femoris, Piriformis Obturator internus and externus Gemelli  Medial / Internal anterior part of Gluteus minimus Gluteus medius Tensor fasciae latae  Knee Joint Largest joint, synovial hinge type Articulating bones: consist of 2 joints Tibiofemoral joints Patellofemoral joint *fibula is not involved in knee joint Capsule of the joint Loose and thin  Consist of typical external fibrous layer & internal synovial membrane  Anteriorly replaced by: 1. Quadriceps femoris tendon 2. Patella 3. Patellar ligament Its synovial membrane communicates superiorly with suprapatellar bursa. Knee Joint: External ligaments Quadriceps muscle tendons - contribute significantly to the stability of knee joint Ligamentum patellae – anterior Oblique ligament – posterior Medial & lateral collateral ligaments – each side Medial & lateral patellar retinacula – each side of patella  Knee Joint: Internal ligaments Cruciate ligaments Intracapsular but extrasynovial Anterior cruciate ligament Origin: anterior intercondylar area of tibia Insertion: lateral condyle of Menisci femur Fibrocartilaginous C-shaped disc Prevents hyperextension As shock absorber & help lubricating the joint cavity Posterior cruciate ligament  Medial meniscus Origin: posterior - larger, less curved than lateral intercondylar area of tibia - attached to medial collateral ligament Insertion: medial condyle  Lateral meniscus of femur - smaller, more freely mobile Prevents hyperflexion - separated from lateral collateral ligament by popliteus tendon Knee Joint - Ligaments  Movements of Knee Joint Flexion Hamstring muscles Sartorius, gracilis Gastrocnemius Extension Quadriceps femoris Locks knee into full extension Gluteus maximus - by way of the iliotibial tract Unlocks full extension and start flexion Popliteus muscle  this muscle pulls on the lateral condyle of the femur causing it to rotate laterally  FOOT JOINTS ANKLE JOINT Type: Synovial hinge joint Articulating bones: tibia and fibula of the leg & talus of the foot  REFERENCES Snell, Richard S.. Clinical Anatomy By Regions, 8th edition (2008), Lippincott Williams & Wilkins, Philadelphia. Moore, K.L., Dalley, Arthur F., Agur, Anne M.R. Clinically Oriented Anatomy, 6th edition (2009), Lippincott Williams & Wilkins, Philadelphia. Richard L. Drake, Wayne Vogl & Adam W.M. Mitchell. Gray’s Anatomy for Students.  teachmeanatomy.info  kenhub.com  Tabulate the differences between male and female pelvis.  State the prime movers of each of the lower limb movements. 118