Clinical Anatomy Of The Lower Limb 1 Flashcards
What are the major bones of the lower limb?
Hip joint: pelvic bone and femur
-ball and socket joint
Knee joint: femur, tibia, patella
- hinge joint
- tibia and fibula linked by interosseous membrane
Ankle joint:
- hinge joint
- tibia, fibula and tarsal bone
.what is the center of gravity?
- Anterior to the edge of the SV2 vertebra in the pelvis
- Anterior to the knee and ankle joints
- Directly over the support base formed by the feet on the ground
What are the stages of gait?
Gait cycle- heel strike to heel strike
Phases:
-stance: 60%
-swing: 40%
What is the structure of the hip joint?
- ball and socket joint
- head of the femur is covered with Articular cartilage
- acetabulum
- partially covered with cartilage
- deepened by fibrocartilage
Surrounded by a capsule:
- proximally attaching to the acetabulum
- distally attaching to the femoral neck
Describe the joint capsule
Three main ligaments of the capsule:
- ilio-femoral ligament:
- AIIS to intertrochanteric line
- prevents hyper-extension
- pubo-femoral ligament
- pubo bone to femur
- ischiopubic-femoral ligament
- ischium to femur
-ligament of the head of femur
What is the gluteal region?
The gluteal region lies to posterolateral to the bony pelvis and proximal end of the femur
What are the lateral rotations of the gluteal region?
Lateral rotators:
- piriformis
- gemelius superior
- obturator internus
- gemelius inferior
- quadratus femoris
What are the extensors of the gluteal region?
-gluteal Maximus
What are the functions of the abductors and medial rotators?
- gluteal medius
- gluteus minimus
What is the motor & Sensory innervation of the gluteal Region?
Branches of sacral plexus
What is the opening(hiatus/foramen) of the gluteal region?
Greater and lesser sciatic foramen
What is the blood supply for the gluteal region?
Branches of internal iliac
What is the innervation and function of tensor fascia Lata?
Superior gluteal nerve
- abducts thigh/hip joint
- stabilizes the knee in extension
What is the function and innervation of gluteus Maximus?
Inferior gluteal nerve
-extends the flexed thigh/hip joint
- lateral stabilizer of the hip and knee
- abducts and assists in lateral rotation of thigh/hip joint
What is the gluteal medius innervation and function?
Superior gluteal nerve
-abducts and medially rotates the thigh/hip joint
Describe normal gait
Contraction of the gluteus medius and minimus on the stance leg (weight bearing limb) prevents excessive downward tilt of the opposite, unsupported pelvis during its swing phase
What are the changes in gait?
-normally, the gluteus medius and minimus contract as soon as contralateral foot leaves the ground, preventing tipping to the unsupported side
- positive Trendelenburg sign:if the superior gluteal nerve is injured, the pelvis on the unsupported side drops when the patient is asked to stand on the affected limb
- waddling gait
What is the function of the piriformis ?
Nerve to piriformis (S1 & S2)
-lateral rotator of the thigh/hip joint & abducts flexed thigh/hip joint
What is the function and innervation of gemellius superior?
Nerve to obturator internus
-lateral rotator of the thigh/hip joint & abducts flexed thigh/hip joints
What is the function and innervation of obturator internus?
Nerve to obturator internus
-lateral rotator of the thigh/hip joint & abducts flexed thigh/hip joint
What is the function and innervation of gemellius inferior?
Nerve to quadratus femoris
-lateral rotator of the thigh/hip joint & abducts flexed thigh/hip joint
What is the innervation and function of quadratus femoris?
Nerve to quadratus femoris
-lateral rotator of the thigh/hip joint
Summarize cutaneous innervation of the gluteal region
- Superior clinical nerve(dorsal rami L1-L3)
- Medial clunial nerve (dorsal rami S1-S3)
- Inferior clunial nerve (ventral rami S1-3 - ascending branches from the posterior femoral cutaneous nerve)
- Iliohypogastric nerve
What is the blood supply to the gluteal region and hip joint ?
Branches of the femoral, inferior gluteal, superior gluteal, and obturator arteries, together with branches from the internal pudendal and femoral arteries interconnect to form an anastomotic network giving blood supply to the hip joint, upper thigh and gluteal region
The presence of these anastomotic channels may provide colateral circulation when one of the vessels is interrupted
Describe trochanteric anastomosis to the hip joint
- branches of medial and lateral circumflex arteries
- inferior gluteal artery
- branch of the superior gluteal
Describe the cruciate anastomosis to hip joint
- branches medial and lateral circumflex femoral arteries
- branch of 1st perforating branch of profunda femoris artery
- branch of inferior gluteal artery
What is the anastomic arteries to the hip joint?
- Superior gluteal- to trochanteric anastomosis only
2,3. Lateral & medial circumflex femoral-off profunda femoris supplying both anastomosis
- Ascending branch of 1st proforator to Cruciate anastomosis only
Summarize blood supply of the head of the femur
Medial and lateral circumflex femoral arteries
-Retinacular branches
Acetabular branch of obturator artery
- Arises as a branch from the obturator artery
- Located in the ligament of head of femur
- decreased or absent as you get older
Describe the fracture of neck and inter-trochanteric area of femur
Common in individuals >60 years old
Classified as:
Intra-capsular fracture of the femoral neck eg subcapital
-Damages the retinacular arteries
-compromises blood supply to the head of femur
-risk of avascular necrosis
Extra-capsular- intertrochanteric fracture
-does not affect blood supply to the joint
Both intra and extracapsular fractures result in external rotation of the leg with some shortening
The fracture caused a decrease in the angle, thus creating a shorter right limb. Thus decrease in Angle between neck and shaft is called ACQUIRED COXA VARA
What is the subcutaneous tissue and deep fascia?
Contains:
- loose connective tissue
- fat
- cutaneous nerves
- superficial veins
- lymphatic vessels and lymph nodes
Describe the deep fascia of the leg
Outer layer stocking like membrane which covers the lower limb, completely surrounding the muscles in the compartments of the thigh and leg
- fascia lata- thickened deep fascia in thigh and gluteal region, attached along a line that defines the upper margin of the lower limb and is continuous with the fascia of the leg inferiorly
- iliotibial tract- longitudinal band along the lateral margin of the limb from Anterolateral tubercle of the iliac crest to the lateral Condyle of the tibia
Fascia cruris- fascia in the leg
The thigh compartments are divided by:
- inter muscular septa at the posterior aspect of the femur (attaches to deep fascia)
- fascia lata(deep fascia)
What are the thigh compartments?
- Posterior compartment
Sciatic nerve
-extend the thigh
-flex the knee - Anterior compartment
Femoral nerve
-flexors of thigh
-extensors of the knee
3. Medial compartment
Obturator nerve
-Adductors of thigh
-Except hamstring part of adductor magnus
-part of pectineus
What are the muscles of the posterior compartment?
- semitendinous
- semimembranous
- biceps femoris(dual innervation)
What is the innervation of the posterior compartment of the thigh?
Sciatic nerve, posterior femoral cutaneous nerve
What is the opening (hiatus) of the posterior compartment of the thigh?
Adductor hiatus
What is the blood supply of the posterior compartment of the thigh?
Perforating branches of deep femoral artery
What are the posterior compartment of the general functions ?
Extension of the hip joint and flexion of the knee joint
Hamstring muscle groups…
Same origin
Same function
Same nerve
What is the function and origin of the semimembranous?
Origin: ischial tuberosity
Function:
- flexes the leg/knee joint
- extends the thigh/hip joint
What is the innervation of the semimembranous muscle?
Sciatic nerve(tibial part)
What is the origin of the bicep femoris?
Origin: long head (LH): ischial tuberosity
Origin: shirt head(SH): femur
What is the innervation of the bicep femoris?
Sciatic nerve: long head(tibial part)
Common fibula part: short head
What is the function of the biceps femoris ?
Long head- fkexes the leg/knee joint. Extends the thigh/hip joint
Short head- flexes the leg/knee joint
Describe the sciatic nerve
Combination of two nerves
- common fibula - tibial
Typically exits the pelvis below the piriformis
Separates proximal to the popliteal fossa
-variations in about 13%
What are the spinal nerve origins of the sciatic nerve?
Tibial nerve- L4-S3
Common fibular-L4-S2
What are the spinal nerve levels of the posterior femoral cutaneous nerve?
S1-S3
What are the muscles for the anterior compartment?
Iliopsoas
Sartorious
Quadriceps femoris
What is the motor and sensory innervation of the anterior compartment?
Femoral nerve
What are the openings(canal ) of the anterior compartment of the thigh?
Femoral canal, subsartorial (adductor/hunter’s) canal
What is the blood supply of the anterior compartment of the thigh?
Femoral artery and it’s branches
What is the general function of the anterior compartment of the thigh?
Flexion at the hip joint. Quadriceps femoris also extends the knee
What are the functions and innervation of the rectus femoris?
Quadriceps femoris tendon, patella ligament
- femoral nerve
- flexes the thigh/hip joint, extends the leg/knee joint
What are the functions and innervation of the castes medialis?
Quadriceps femoris tendon, patella ligament
- femoral nerve
- extends the leg/ knee joint
What are the functions and innervation of the ilio-psoas?
- anterior rami L1-3/femoral nerve
- flexes the thigh/hip joint
What are the innervation and functions of the sartorius muscle?
Femoral nerve
- flexes the thigh/hip joint
- flexes the leg/knee joint
What are the muscles of the medial compartment of the thigh?
- Pectineus(dual innervation)
- gracilis
- adductors
- obturator externus
What are the motor and sensory innervation of the medial compartment of the thigh?
Obturator & tibial nerves
What is the opening(canal) of the medial compartment of the thigh?
Subsartorial (adductor/hunters) canal
What is the blood supply of the medial compartment of the thigh?
Obturator artery
What is the general function of a medial compartment of the thigh?
Adduction of the hip, except obturator externus
What is the innervation and function of the adductor longus?
Obturator nerve
Adducts and medially rotates the thigh/hip joint
What is the function and innervation of adductor brevis?
- obturator nerve
- adducts and medially/hip joint
What are the functions and innervation 9f the adductor magnus?
Adductor part: obturator nerve
Hamstring part: sciatic (tibial) nerve
-adductor and medially/hip joint
What are the functions and innervation of the pectineus muscle?
- femoral and obturator nerve
- adducts and flexes thigh/hip joint
What are the functions and innervation of gracilis?
Obturator nerve
Adducts thigh and flexes leg/knee joint
What is the function and innervation of the obturator externus?
- obturator nerve
- lateral rotation of the thigh/hip joint
Summarize blood supply the thigh
Femoral artery is palpable at the femoral triangle inferior to the inguinal ligament midway between the anterior superior iliac spine and the pubic symphysis
Describe the lateral circumflex artery of the profundus artery
Lateral circumflex femoral artery:
- passes deep to sartorius and rectus femoris
- ascending branch
- descending branch
- transverse branch
Describe the medial circumflex femoral artery of the profunda femoris
- one branch ascends to the trochanter fossa
- one passes laterally to participate in the Cruciate anastomosis
Describe the perforating arteries of the profunda femoris
- penetrate adductor magnus and supply posterior compartment
- ascending and descending branches that interconnect forming a longitudinal channel
What is femoral sheath?
Inferior extension of the transversalis fascia and the iliopsoas fascia from the abdomen
What are the 3 compartments of the femoral sheath?
Divided internally into three smaller compartments by connective tissue:
- the lateral compartment- the femoral artery
- the intermediate compartment-the femoral vein
- the most medial compartment- the femoral canal-contains lymph nodes
- Femoral ring: opening of this canal superiorly is potentially a weak point in the lower abdomen and is the site of femoral hernias
The femoral nerve is lateral to but NOT contained within the femoral sheath
What is the femoral triangle?
A wedge shaped depression formed by muscles in the upper thigh
-contains strictures coming from the abdomen
What are the bo4ders of the femoral triangle?
- superior: inguinal ligament(forms the base)
- medial: medial border of the adductor longus
- lateral: medial border of the sartorious
- Roof: fascia lata
- floor: pectineus, iliopsoas and the adductor longus
What is the adductor canal?
Fascail tunnel in the middle third of the thigh, extending from the apex of the femoral triangle to the opening in the adductor magnus
What are the contents of the adductor canal?
Femoral artery, vein and the saphenous nerve
Describe the blood vessels of the adductor canal
Femoral artery enters the adductor hiatus, and exits as the popliteal artery, popliteal vein enters the adductor hiatus and becomes femoral vein
Saphenous nerve although in the adductor canal, does not enter the adductor hiatus. It leaves the canal and continues its course to the medial side of the lower extremity
