Lower Limb Anatomy 2021 PDF

Joint Medical Program Mr Ryan Harris [email protected]  COMMONWEALTH OF AUSTRALIA Copyright Act 1968 notice required for paragraph 135ZXA(a) of the Copyright Act 1968 WARNING This material has been reproduced and comm...

Joint Medical Program Mr Ryan Harris [email protected]  COMMONWEALTH OF AUSTRALIA Copyright Act 1968 notice required for paragraph 135ZXA(a) of the Copyright Act 1968 WARNING This material has been reproduced and communicated to you by or on behalf of the Joint medical program under Part VB of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Do not remove this notice.  Revise the anatomy of the lower limb skeleton Bones – Pelvis & hip Fractured neck of femur Intracapsular – more likely to result in avascular necrosis of femoral head Extracapsular – beyond joint capsule, ~ intertrochanteric line/ crest  Cannulated hip screws Dynamic hip screws (CHS) (DHS) Fractured neck of femur Hip arthroplasty (THR) Ligaments – Hip & pelvis  Common in two demographics Hip dislocation Congenital dislocation (DDH) Elderly – traumatic dislocation Bones – Femur and knee ACL tears PCL ACL tear ACL PCL tears PCL ACL Meniscal tears Medial Lateral Terrible triad MCL ACL Medial meniscus Knee – arthroplasty (TKR) Bones – Tibia, fibula & ankle  Shin splints ◼ Excessive & repetitive loads ◼ Inflammation of periosteum Baker’s cyst Ankle Sprains & High ankle fracture Bones – Foot Arches & flat feet Bunions & hammertoe  Revise the anatomy of the lower limb skeleton Describe the nerves which are clinically important in lower limb injuries Lumbo-sacral plexus Obturator nerve Anterior branches of L2 – L4 Travels through obturator canal Innervates the adductor muscle group (and obturator externus) in medial compartment of thigh Femoral Nerve Posterior branches of L2 – L4 Travels under inguinal ligament into femoral triangle Innervates the quadriceps & iliopsoas (and pectineus & sartorius) in anterior compartment of thigh Sciatic Nerve L4 – S3 Travels through greater sciatic foramen and under piriformis Innervates entire leg except anterior & medial thigh compartments Divides into Tibial & Common Fibular nerves Sciatica Tibial nerve Innervates: ◼ Hamstrings (except short head of biceps femoris) ◼ All posterior compartment of leg muscles ◼ All foot muscles (except short extensor muscles) Common fibular nerve ◼ Divides into superficial and deep branches ◼ Deep branch innervates the anterior muscles of the leg ◼ Superficial branch innervates the lateral compartment  Foot drop ◼ Common fibular nerve ◼ Deficient dorsiflexion ◼ Common reasons? ◼ Gait change ❑ Slapping / high stepping Cutaneous innervation Cutaneous innervation Other nerves Superior gluteal n. – glute med, glute min, TFL Nerve to piriformis Nerve to obturator internus Inferior gluteal n. – glute max Nerve to quadratus femoris  Revise the anatomy of the lower limb skeleton Briefly describe the blood supply of the lower limb Describe the anatomical basis of DVT and varicose veins  Weak or damaged valves Veins pool, stretch and twist DVT  Revise the anatomy of the lower limb skeleton Briefly describe lower limb compartments and major muscles Describe the anatomical adaptation to stabilise the knee and ankle joints Actions: Hip: Flexion (and lateral rotation) Origins: Iliacus – iliac fossa Psoas major – lumbar vertebrae (T12 – L5) Insertions: lesser trochanter Gluteus maximus Actions: Hip: Extension, lateral rotation, abduction and adduction Knee: stabilises lateral side through ITB Origins: - Insertions: gluteal tuberosity & ITB Tensor fasciae latae Actions: Hip: abduction & medial rotation Origin: - Insertion: ITB Gluteus medius & minimus Actions: Hip abduction + hip medial rotation Origins: gluteal surface Insertions: greater trochanter Gluteus medius & minimus chronic injuries Trendelenburg gait Trochanteric bursitis Lateral Rotators of the Hip Joint Piriformis Gemellus superior Obturator internus Gemellus inferior Obturator externus Quadratus femoris Can also support abduction and adduction, depending on the actual position of the femur axis of ab-/adduction All insert on to greater trochanter (except quadratus femoris) Piriformis syndrome -divides the greater sciatic foramen in a supra- and infrapiriform foramen -can cause compression of sciatic nerve = piriformis syndrome Compartments Anterior compartment Lateral Posterior compartment compartment Thigh Leg Compartment syndrome Quadriceps femoris Actions: Rectus femoris - extends knee, flexes hip joint Vastus medialis Vastus lateralis extends knee Vastus intermedius Most stabilising factor at knee Origins: - Insertion: Patella; and tibial tuberosity via patellar ligament Patellar maltracking Patellofemoral syndrome Overuse (and excessive forces), weak muscles, improper set-up Osgood-Schlatter’s Disease Overuse (and excessive forces) resulting in either tibial tuberosity avulsions or pressure on epiphyseal plate Sartorius The “Tailor’s Muscle”: - brings lower limbs into the cross-legged sitting position Origin – ASIS Insertion – Pes anserinus Pectineus Functionally, it can be grouped together with the adductor muscles Forms part of floor of femoral triangle Adductors Adductor longus Adductor brevis Adductor magnus Gracilis Obturator externus Action: Adduct the hip joint (all muscles can support flexion or extension of the hip joint depending on the joint position) Origin: pubis Insertion: linea aspera Adductor Magnus ◼ Largest & most powerful adductor muscle ◼ Adductor part: adducts hip ◼ Hamstring part: extends hip and provides a tunnel for the femoral artery and vein Innervated by obturator nerve Innervated by sciatic nerve Common muscle strains “Groin injury” Pes anserinus Common attachment site of the: Sartorius Gracilis Semitendinosus “SGT” Common attachment site of: ◼ Semimembranosus ◼ Semitendinosus ◼ Biceps femoris (long head); and ◼ Adductor magnus Semimembranosus Medial Semitendinosus Flex and medially rotate knee joint (also: extension of hip joint) Biceps femoris Lateral Flexes and laterally rotates knee joint Long head also: Extension of hip joint Plantarflexors Gastrocnemius Soleus Plantaris Tibialis posterior Flexor digitorum longus Flexor hallucis longus “Unlocks the knee” Popliteus Evertors Fibularis longus Fibularis brevis References Drake, R. L., Vogl, W., Mitchell, A. W. M., & Gray, H. (2005). Gray's anatomy for students. Philadelphia: Elsevier/Churchill Livingstone. Gilroy, A. M., MacPherson, B. R., & Ross, L. M. (2008). Atlas of anatomy. Stuttgart: Thieme. Marieb, E. N., & Hoehn, K. (2016). Human anatomy & physiology (10th ed.). Boston: Pearson. Moore, K. L., Dalley, A. F., & Agur, A. M. R. (2010). Clinically Oriented Anatomy (6th ed.). Philadelphia: Lippincott Williams & Wilkins www.radiopedia.com