L02 – Lower Limb Bones & Joints Flashcards
What are the 6 regions of the free lower limb?
1) Gluteal region
2) Thigh/ Femoral region
3) Knee region
4) Leg region
5) Ankle/ Talocrural region
6) Foot region
Name all the bones in the lower limb.
Hip bone Femur Patella Fibula & Tibia Larger and smaller tarsal bones Metatarsals Phalanges
What is the carrying angle of the lower limb?
14-17 degrees
more obvious in woman
What are the three parts that make up the hip bone?
Ilium
Ischium
Pubis
What are the bony prominence on each of the 3 parts of the hip bone?
Ilium = Anterior superior iliac spine (ASIS), Posterior superior iliac spine (PSIS), Greater sciatic notch, Iliac crest
Ilium: Ischial tuberosity, Lesser sciatic notch, Ischial spine
Pubis: Pubic tubercule
Ischium and pubis make up the Obturator foramen
What are the bony features on the anterior of the femur?
Head
Neck
Greater and Lesser trochanter separated in the middle by Intertrochanteric line
Shaft @ anterior is smooth
From lateral to medial at the distal end:
Lateral epicondyle > Lateral condyle > Medial condyle > Medial epicondyle
What are the bony features on the posterior of the femur?
Head
Neck
Intertrochanteric crest is superior to Quadrate tubercle
Gluteal tuberosity
Linea aspera on the shaft
Lateral condyle and Medial condyle separated by Intercondylar fossa
What are the angles of inclination and anteversion of femur?
Angle of inclination ~125°
Angle of anteversion or femoral torsion (~12°)
Which bones in the lower limb are weight- bearing?
femur
tibia
talus
calcaneus and the heads of metatarsals
How is patella bone localized at the knee?
Attached to Quadriceps tendon superiorly
Attached to Ligamentum patellae inferior
What is the function of the patella?
Seasamoid bone that protects the Quad. tendon from daily wear
Describe the bony features of the tibia anteriorly and posteriorly?
Anteriorly and Posteriorly: medal condyle @ proximal end; medial malleolus @ distal end
Anterior: Tibial tuberosity (to attach Ligamentum patallae)
Posterior: Soleal line (to attach Soleus muscle)
List the name and number of bones of the foot?
2 Large tarsal bones: Talus, Calcaneus
5 Small tarsal bones: Cuboid, Navicular, Cuneiform (lateral, intermediate, medial)
5 Metatarsals
Phalanges (2 in big toe, 3 in the other digits)
Describe the structure of the sacroiliac joint?
Synovial plane joint (auricular surface on ilium articulates with corresponding
surface on sacrum)
Stabilized by ligaments:
- Sacrospinous ligament
- Sacrotuberous ligament
- Posterior Sacroiliac ligaments
- Interosseous sacroiliac ligaments
What type of joint is hip joint?
(synovial ball-and-socket joint)
Describe the structure of the hip joint?
Synovial sheath reflected onto neck of femur
Ligament of the head of femur (ligamentum teres) connects Fovea capitis on the femur head and fibrous capsule
How is the hip joint stabilized?
The fibres of the capsule are arranged spirally and are thickened to form 3
ligaments (iliofemoral, pubofemoral, ischiofemoral).
Iliofemoral ligament is
the strongest.
Ligamentum teres is the weak, prone to break
What are the most stable and unstable positions of the hip joint?
1) Most stable position - slightly hyperextended (ligaments wind/ spiral and force the articular surfaces closer together)
2) Most unstable position - flexed and adducted
(ligaments slack and long)
Location of common hip joint dislocations?
Most dislocations are posterior
What are some consequences of hip joint fracture?
endangers sciatic nerve
may tear ligamentum teres and its artery»_space; avascular necrosis of the femoral head
What are the 3 types of common femur fracture?
Intertrochanteric Subtrochanteric Intracapsular (risk of avascular necrosis)
Blood supply to femoral head?
Artery of ligamentum teres
Nutrient artery
Deep femoral artery»_space; Medial and lateral circumflex femoral artery»_space; Capsular/ Retinacular arteries (main)
What gives rise to capsular or retinacular arteries? What is the course of these arteries?
Branches of medial and lateral circumflex
femoral arteries from Deep femoral artery
pierce the joint capsule and run beneath the synovial membrane along the femoral neck
> > enter the femoral head through small holes
What gives rise to artery of ligamentum teres?
branch of the obturator artery
What type of joint is the knee joint?
synovial condyloid or modified hinge joint between femur and tibia
synovial plane joint between femur and patella
What is the ROM of the knee joint?
Mainly flexion and extension but some rotation is possible when the joint is flexed.
Medial rotation of femur (relative to tibia) occurs during the last phase of extension
Explain how the femur rotates medially during the last phase of extension?
Medial condyle is larger than lateral condyle
2 condyles ‘roll’ until lateral condyle reaches limit of rotation, then medial condyle rotates for additional range.
Describe the synovial cavity of the knee joint?
Extensive synovial cavity with a number of bursae communicating with it:
Suprapatellar bursa
Prepatellar bursa
Deep infrapatellar bursa
Subcutaneous infrapatellar bursa
What muscle contracts to laterally rotate the femur relative to tibia and ‘unlock the knee’?
Popliteus muscle
Which bursa of the knee is prone to bursitis?
prepatallar, infrapatellar bursa
List the ligaments of the knee joint?
Anterior & Posterior cruciate ligaments
Tibial collateral ligament
Fibular collateral ligament
What are the roles of the ligaments of the knee?
Anterior and posterior cruciate ligaments = help maintain anteroposterior stability, prevent excessive anterior femoral shift or posterior tibial shift
Tibial and Fibular collateral ligaments = maintain transverse stability
Both = maintain rotational stability
What is injured in the knee after landing obliquely on a hyperextended leg?
Injury to anterior cruciate ligament due to twisting of hyper-extended knee
Medial side most prone to injuries*
What is injured in the knee after being hit by a car side-on?
Medial collateral ligament tear
What is the most important stabilizing factor of the knee joint?
Muscle tone of Quadriceps Femoris is the most
important stabilizing factor
What is the most stable position of the knee joint?
full extension. The femur rotates medially on the tibia during full extension
> > all ligaments taut, knee in
“screwing-home” position
What is injured when the leg is laterally rotated very quickly?
Injury to medial meniscus at the proximal end of tibia
Rapid rotation beyond ROM causes the meniscus to be crushed
What type of joint is the inferior tibiofibular joint?
syndesmosis/fibrous joint
What is the inferior tibiofibular joint stabilized by?
Anterior tibiofibular ligament
Posterior tibiofibular ligament
Interosseous ligament
Compare the Superior and Inferior tibiofibular joint?
Superior/proximal tibiofibular joint: Synovial plane joint.
Inferior/distal tibiofibular joint: Syndesmosis.
How does the tibia and the foot fit togehter?
Medial malleolus of the tibia and the talus of the foot fit in Mortise and Tenon way
What are the collateral ligaments of the ankle joint?
Medial side: Deltoid ligament
Lateral: Anterior & Posterior talofibular ligament + Calcaneofibular ligament
What type of joint is the ankle joint?
synovial hinge joint
What position of the ankle joint is stable and unstable?
Stable = Dorsiflexed
Unstable = Plantar flexed
What structure of the ankle joint is injured by excessive inversion?
Increase tension on the lateral side:
Sprain of calcaneofibular ligament
> Avulsion of lateral malleolus of fibula (bone fracture by being pulled apart)
> > “Push fracture” of the medial malleolus of tibia
What structure of the ankle joint is injured by excessive eversion?
Excessive tension on the medial side:
Avulsion of medial malleolus of tibia
> > Push fracture of lateral malleolus of fibula
What are the joints of the foot?
Calcaneocuboid joint (plane joint) Talonavicular joint (plane joint)
Subtalar and Transverse tarsal joint form the STTN complex
Tarsometatarsal joints (plane joint)
Metatarsophalangeal joints (condylar/ellipsoid joints)
Interphalangeal joints (hinge)
What are the plantar ligaments of the foot?
Long plantar lig.
Spring lig.
Short plantar lig.
What is the ligament between the Talus and the Calcanues?
Talocalcaneal intersseous ligament
How is the foot arch maintained by ligaments? Mechanisms of foot support?
Tie in concavity e.g. plantar ligaments, short muscles
Tie near concavity e.g. interosseous ligaments
Tie between bases e.g. plantar aponeurosis
Sling e.g. Peroneus longus
Tie e.g. Tibialis anterior
