Thigh and knee Flashcards
What is the anteversion of the femoral neck?
15-20 degrees
What is the articularis genu?
Small muscle on the anterior aspect of the distal femur deep to vastus intermedius
O: anterior surface of distal femur, deep to vastus intermedius
I: synovial membrane of knee
I: femoral nerve
A: pulls the suprapatellar bursa superiorly during knee extension, preventing impingement of the bursa between patellar and femur
What innervates adductor Magnus?
Obturator (posterior branch) & sciatic (tibial portion)
What are the origins and insertions of biceps femoris?
O:
Long head: ischial tubeosity (with semitendinosus)
Short head: lateral linea aspera, lateral supracondylar ridge
I: fibular head, LCL, lateral tibial condyle
What comprises the conjoint tendon of the thigh?
Long head of biceps femoris & semitendinosus
Name the insertion sites of semimimbranosus:
Posterior medial tibial condyle
posterior capsule and posterior horn of medial meniscus
oblique popiteal ligament
posterior oblique ligament
popliteus aponeurosis
What are the borders of the adductor canal? Its contents?
Lateral: vastus medialis
Medial: sartorius
Floor: adductor longus/Magnus
Contents:
Femoral artery and vein
saphenous nerve
nerve to vastus medialis
***Note that the picture below has the vessels passing through the adductor hiatus of adductor magnus with a large portion of the muscle medially and a smaller portion laterally
What are the borders of the adductor canal? Its contents?
Lateral: vastus medialis
Medial: sartorius
Floor: adductor longus/Magnus
Contents:
Femoral artery and vein
saphenous nerve
nerve to vastus medialis
***Note that the picture below has the vessels passing through the adductor hiatus of adductor magnus with a large portion of the muscle medially and a smaller portion laterally
What vessels are included in the Cruciate anastamosis? Where is it located?
1st perforating branch of the profunda femoris (main)
Medial femoral circumflex artery
Lateral femoral circumflex artery
Inferior gluteal artery
Located at the inferior margin of quadratus femoris
What degree is the tibial slope?
8-10 degrees posterior
What is the average thickness of the largest sesamoid bone in the body?
23-25mm Note: in TKA, it should not be cut to a thickness of less than 12-15mm as this increases the risk of patellar fracture
Describe the anatomic axis of the femur and tibia?
A line that runs down the intramedullary canal of the femur and tibia, respectively
How do you measure Q-angle? What are normal values in men and women?
What are 4 ways to increase Q-angles in TKA? (this is bad and should be avoided!)
Angle between a line from ASIS to the patellar centre and another extending proximally from tibial tubercle through patellar centre Normal: Men: 14 degrees Women: 17 degrees
In TKA you must ensure you dont:
- internally rotate the femoral component
- internally rotate the tibial component
- medialize the femoral component
- lateralize the patellar component
Name the 12 ligaments of the knee:
there are more than 12:
ACL
PCL
LCL
MCL
MPFL
Arcuate ligament
Oblique popliteal ligament
Retinacular ligament
Coronary ligament
Wrisberg ligament
Humphrey ligament
Transverse ligament
posterior oblique ligament
popliteofibular ligament
(ligamentum mucosum is not a ligament - misnomer - it is a plica)
Which ligaments of the knee contribute to the fibrous capsule of the knee posteriorly?
Medially:
- Oblique popliteal ligament: semimimbranosus to posterior wall of capsule
Laterally:
- Arcuate ligament: Y-shaped fibres from fibular head
- popliteal muscle to the posterior capsule
- LCL contributes to joint capsule
Which ligaments of the knee have attachments to the menisci (5)?
- MCL
- Coronary ligament: peripheral menisci to capsule/tibia
- Transverse: aka anterior intermeniscal ligament
- Wrisberg: behind PCL from posterior lateral meniscus to medial femoral condyle
- Humphrey: in front of PCL from posterior lateral meniscus to medial femoral condyle
Which parts of the ACL and PCL are tight in flexion? Extension?
- PCL
- AL
- PM
- **Remeber PAL (PCL has AL bundle)
- ACL
- AM
- PL
Tight in flexion: PCL: anterolateral ACL: anteromedial
Tight in extension: PCL: posteromedial ACL: posterolateral
When is the ACL tightest?
In extension
Name the layers of the medial aspect of the knee and each layer’s contents:
What are the medial layers of the knee:
Layer 1
- Sartorius
- fascia
- patellar retinaculum
**gracilis, semitendinosis, and saphenous nerve run between layer 1 and 2
Layer 2
- superficial MCL
- posterior oblique ligament
- semimembranosis
- MPFL
Layer 3
- deep MCL
- capsule
- coronary ligament
What are the layers of the lateral aspect of the knee and their contents?
What are the lateral layers of the knee (according to Orthobullets)
Layer 1:
- - IT tract
- - biceps femoris
Common Peroneal nerve lies between layers 1 and 2
Layer 2:
- - Patellar retinaculum
Layer 3:
Superficial:
- LCL
- fabellofibular ligament
- ALL
****Lateral geniculate artery runs between deep and superficial layers
Deep:
- popliteus tendon
- Arcuate ligament
- popliteofibular ligament
- coronary ligament
- capsule
What part of the tibial plateau is concave and convex?
Medial is concave
Lateral is convex
What is the insertion of the IT band?
Gerdys tubercle
What is the insertion of the patellar tendon
tibial tubercle
What is the usual deformity of a proximal one third tibia fracture
valgus and procurvatum
(from Pes and extensor mechanism)
What attaches at the fibular head?
LCL
Biceps femoris tendon
What structure wraps around the neck of the fibula
Common peroneal nerve
What surface of the distal fibula is flat and accommodates plating
Posterolateral surface
What type of joint is the proximal tibiofibular joint and what ligaments strengthen it
(Arthrodial) Plane gliding joint
Stabilized by:
Anterior Superior Tib-fib ligament
Posterior Superior Tib-fib ligament
Name the four compartments of the leg
Anterior
Lateral
Superficial posterior
Deep posterior
Name the Contents of the anterior compartment of the leg
Anterior tibial artery and vein
Deep peroneal nerve
Muscles:
Tibialis anterior
EHL
EDL
Sometimes peroneus tertius (not in lateral compartment)
What is the innervation and blood supply to the anterior compartment of the leg?
Deep peroneal nerve
Anterior tibial artery
Where does the NV bundle run in the anterior compartment of the leg
Runs along the interosseous membrane, deep to the muscles - Its always surrounded by fat
With respect to the neurovascular bundle of the anterior compartment of the leg, describe its course at and below the ankle:
Above: between tibialis anterior and EHL (medial to EHL)
At the ankle: Crosses UNDER EHL
Below: Runs lateral to EHL
What are the contents of the lateral compartment of the leg
Peroneus longus - Superficial and very tendinous Peroneus brevis -superficial peroneal nerve
*SPN runs in anterior compartment ~25% of the time
What is the innervation of the lateral compartment of the leg
Superficial Peroneal Nerve
What is the orientation of the peroneal tendons above the ankle and once they dive behind the fibula
Above the distal fibula: - Longus is superficial to brevis Behind the fibula: - Longus is posterior to brevis in the groove
Longus then passes under the brevis and dives deep to insertions in the midfoot
Describe the tendon sheath of the peroneal tendons
They run in a common sheath until they are past the distal fibula, then they divide into individual tendon sheaths
Name the retinaculae that covers the peroneal tendons
Superior peroneal retinaculum
Inferior peroneal retinaculum
Name the contents of the deep posterior compartment of the leg
Posterior tibial artery
Peroneal artery
Tibial nerve
Muscles: - Tibialis posterior - FHL - FDL
Remember the orientation in the mid tibia is not the same at the ankle.
At ankle - Tom, Dick Harry
At the mid tibia - Dick, tom, harry
The FDL crosses over TP to lie lateral.
Remember that FDL also crosses UNDER the FHL at the knot of henry.
What is the arrangement of the muscles on the posterior compartment of the leg proximal to the ankle and at the ankle
Proximal to the ankle: - Medial to lateral: (opposite of what you’d think) - FDL - tibialis posterior - FHL
At the level of the ankle: - All structures pass posterior to the medial malleolus - Tom Dick And a Very Nervous Harry - This is A to P, M to L
NOTE: FHL is fleshy all the way down so its the fleshy one when you cut there
What is the innervation of the posterior compartment of the leg
Tibial nerve
Name the contents of the Superfical posterior compartment of the leg
Gastrocnemius
Soleus
Plantaris
Strictly speaking, no nerves or vessels run in this compartment - they are either superficial or deep
What is the innervation of peroneus tertius?
Deep peroneal nerve (NOT superficial) - It runs in the anterior compartment, not the lateral
What compartment does perneus tertius run in?
Anterior compartment
What is the action of peroneus longus?
Everts, plantarflexes
(Brevis is an everter and WEAK plantarflexor)
What are the muscles (2) of the lower leg that cross 2 joints?
What are the muscles (7) of the upper leg that cross 2 joints?
Lower leg:
- Gastrocnemius - Medial and lateral femoral condyle to Achilles
- Plantaris - Lateral femoral condyle to calcaneus (NOT via Achilles) - Runs medial to Achilles tendon
Upper leg:
- Sartorius
- TFL
- Rectus femoris
- (Gracilis)
- SemiT, SemiMem, Biceps femoris
On which side of the Achilles tendon does plantaris run?
Medially, see image
What portion of the popliteus muscle is tendinous. What is its action?
What is it’s origin and insertion?
- Proximal part is tendinous
- its origin is distal to its insertion
- Action is to unlock the knee from extension, initiating flexion - Remember, last few degrees of extension, the tibia ERs the leg to lock it into extension
Origin: Posterior surface of tibia - above soleal line
Insertion: Lateral condyle of femur just inferior to LCL origin, Also gives slips to fibular head and the posterior horn of lateral meniscus
Innervation: Tibial Nerve
Describe the course of the tibial nerve
Larger terminal branch of the sciatic nerve
- Popliteal fossa
- Medial sural cutaneous nerve branches here
- Crosses on top of plantaris, popliteus
- Dives deep to soleus through soleal arch and enters deep compartment
- Travels down deep posterior compartment of the leg
- Just deep to transverse intermuscular septum
- Runs with posterior tibial artery and vein, between FDL & FHL
- Supplies all muscles in superficial and deep posterior compartments
- Passes posterior to medial malleolus, through tarsal tunnel
- Divides into: medial and lateral plantar nerves
What nerve does the medial sural cutaneous nerve branch from?
tibial nerve, comes off in the popliteal fossa
Describe the course of the common peroneal nerve.
Small terminal branch of the sciatic nerve
terminal branch of the sciatic nerve
bifurcates in the popliteal fossa
runs medial and just anterior to biceps femoris
runs over the lateral head of gastric
- comes from out behind the biceps once it is passed the knee joint and curves anterolaterally to come around the head of the fibula 3-4 cm distal to the tip. It then pierces the POSTERIOR intermuscular septum to come into the lateral compartment where it BIFURCATES. The deep peroneal nerve then continues through the anterior intramuscular septum to the anterior compartment where innervates TA, EDL, EHL, and PT
Describe the course of the deep peroneal nerve
- Branch of the common peroneal nerve
- Makes a sharp turn and enters the anterior compartment through anterior septum
- Travels along anterior surface of IoM with anterior tibial artery
- Supplies all the muscles in the anterior compartment
- Passes deep to the extensor retinaculum - Supplies EDB
Describe the course of the superficial peroneal nerve:
- Branch of the common peroneal nerve
- Runs in the lateral compartment
- Proximal one third runs on the lateral surface of the fibula
- Then runs under peroneus longus and on top of brevis (between them)
- It then heads anterior and runs between brevis and EDL between the lateral and anterior compartments
- Pierces fascia 10-12cm above the lateral malleolus to run subcutaneously
- Runs in fat, above fascia, down to the ankle
- Runs just anterior to fibula
- Bifurcates into the medial dorsal cutaneous nerve and intermediate dorsal cutaneous nerve
The saphenous nerve is a branch of which nerve?
Saphenous nerve (L3, 4) • Branches off femoral nerve at apex of femoral triangle and travels under the sartorius muscle • Becomes subcutaneous on medial aspect of knee between the sartorius and gracilis; travels with greater saphenous vein • At risk with medial meniscus repair, hamstring harvest • Supplies sensation to the medial aspect of the leg and foot • Infrapatellar branch supplies skin of the medial side of the front of the knee and patellar ligament and can be damaged during total knee replacement surgery or patella tendon harvest. • Terminal branch supplies sensation to medial ankle and foot.
Terminal branch of the femoral nerve
Describe the course of the popliteal artery
Popliteal artery travels posterior to the knee and is the primary blood supply to the leg
• Enters the popliteal fossa between the biceps and semimembranosus and descends underneath the tibial nerve, terminating between the medial and lateral heads of the gastrocnemius and dividing into the anterior and posterior tibial arteries
• Vein usually posterior to artery
• At risk with knee dislocation and trauma about the knee
• Several genicular branches are given off in the popliteal fossa, including the medial and lateral geniculate arteries (which supply the menisci) and the middle geniculate artery (which supplies the cruciate ligaments).
• Superior lateral geniculate artery can be injured during lateral-release procedures.
• Descending geniculate artery (branch of femoral artery proximal to Hunter canal) supplies the vastus medialis at the anterior border of the intermuscular septum. • Inferior geniculate artery passes between the popliteal tendon and the fibular collateral ligament in the posterolateral corner of the knee.
Continuation of the superficial femoral artery
- Enters the popliteal fossa between biceps femoris and semimembranosus
- Runs with (lateral to medial)
- tibial n
- popliteal vein
- popliteal artery
- Artery is always medial
- Artery lies behind the posterior horn of the lateral meniscus, 9mm posterior to the posterior aspect of the tibial plateau in 90 deg of flexion
- Passes superficial to popliteus
- Deep to gastrocsésoleus and tibial nerve under a fibrous arch
- Bifurcates at the distal aspect of the popliteus muscle - Anterior tibial artery and tibioperoneal trunk
- Tibioperoneal trunk runs superficial to tib post
- Divides into posterior tibial artery and peroneal artery, 2.5cm distal to popliteal fossa
Name the structures
Answers:
What are the borders and contents of the femoral triangle?
Boundaries:
Superior: Inguinal ligament
Lateral: Sartorius
Medial: Adductor longus
Floor: iliopsoas, pectineus, adductor longus
Contents:
NAVEL towards the navel
nerve, artery (Deep profunda branch), vein (great saphenous vein), empty, lymphatics
Name the bursa around the knee (4):
- Suprapatellar: extension of synovium under tendon of quadriceps femoris
- Prepatellar (housemaids knee)
- Infrapatellar: x2
- Superficial: clergyman’s knee
- Deep (to patellar ligament)
Name the borders and contents of the popliteal fossa:
Borders: Diamond shaped region behind the knee:
Semimembranosus
Biceps femoris
Medial heads of gastrocs
Lateral heads of gastrocs/plantaris
Contents:
Popliteal vessels
Tibial and common peroneal nerves (from sciatic)
Superficial to it: short/small saphenous veins draining into popliteal vein
In a lateral approach to the knee, the most endangered structure is:
Lateral superior geniculate artery
Lateral inferior geniculate vein
Lateral inferior genicular artery
Lateral superior geniculate vein
Lateral collateral artery
Lateral Superior geniculate artery
Where does the MPFL insert on the patella?
What about the femur?
- Patella - Superior medial aspect
- Femur -Schottle’s Point – isometric point for insertion of MPFL
- A reproducible anatomical and radiographic point:
- 1 mm anterior to the posterior cortex extension line
- 2.5 mm distal to the posterior origin of the medial femoral condyle, and proximal to the level of the posterior point of the Blumensaat line
- on a lateral radiograph with both posterior condyles projected in the same plane, shows the mean femoral medial patellofemoral ligament center.
OINA of biceps femoris
O:
Long head: ischial tuberosity: common/conjoint tendon with semitendinosus
Short head: Lateral lip of linea aspera, lateral supracondylar ridge of femur, lateral intermuscular septum of thigh
I:
Fibular head & LCL and lateral tibial condyle
N:
Long head: tibial nerve
Short head: common peroneal nerve (Short head is the only innervation of the peroneal nerve proximal to the knee)
A: flexes knee
Rotates tibia laterally
Long head helps extend the hip
OINA Semitendinosus
O: Common/conjoint tendon with long head of biceps femoris from superior medial quadrant of posterior portion of ischial tuberosity
I: Pes anserinus
N: Tibial branch of sciatic nerve
A: extends thigh and flexes the knee
Also rotates tibia, especially when knee is flexed
OINA of Semimembranosus
O: Superior lateral quadrant of the ischial tuberosity
I: Posterior surfae of the medial tibial condyle (5 insertion sites)
N: Tibial portion of sciatic nerve
A: Extends thigh, flexes knee, rotates tibia medially especially when knee is flexed
OINA of Gluteus medius
O: Dorsal ilium inferior to iliac crest
I: Lateral and superior surfaces of GT
N: Superior gluteal nerve
A: Major abductor ot thigh
Superior fibers help rotate thigh medially
Posterior fibers help rotate thigh laterally
OINA of Tensor fascia lata
O:
ASIS
Outer lip of anterior iliac crest and fascia lata
I: IT Band
N: Superior gluteal nerve
A: Stabilizes hip and knee joints by putting tension on the IT band of fascia
Name the plane and dangers to the anteromedial approach to the distal femur:
Plane:
V. medialis (femoral) & rectus femoris (femoral), both innervated proxially
Dangers:
Medial superior geniculate artery
Detachment of vastus medialis needs to be reattached to patella
Notch sign: medial or lateral femoral condyle?
Lateral
The (deep) lateral femoral notch sign describes a depression on the lateral femoral condyle at the terminal sulcus, a junction between the weight bearing tibial articular surface and the patellar articular surface of the femoral condyle.
An abnormally large notch or an asymmetrical/irregular notch can be an indirect sign of an ACL injury as evidence of a pivot shift mechanism and rotatory subluxation.
What are the branches of the femoral artery?
- superficial circumflex iliac artery
- superficial epigastric artery
- superficial external pudendal artery
- deep external pudendal artery
- profunda femoris artery
- Lateral circumflex femoral artery
Medial circumflex femoral artery
Perforating arteries - perforate the adductor magnus muscle to the posterior and medial compartments of the thigh.
- descending genicular artery
Details:
- The superficial circumflex iliac artery is a small branch that runs up to the region of the anterior superior iliac spine.
- The superficial epigastric artery is a small branch that crosses the inguinal ligament and runs to the region of the umbilicus.
- The superficial external pudendal artery is a small branch that runs medially to supply the skin of the scrotum (or labium majus).
- The deep external pudendal artery runs medially and supplies the skin of the scrotum (or labium majus).
- The profunda femoris artery is a large and important branch that arises from the lateral side of the femoral artery about 1.5 in. (4 cm) below the inguinal ligament. It passes medially behind the femoral vessels and enters the medial fascial compartment of the thigh. It ends by becoming the fourth perforating artery. At its origin, it gives off the medial and lateral femoral circumflex arteries, and during its course it gives off three perforating arteries.
- The descending genicular artery is a small branch that arises from the femoral artery near its termination within the adductor canal. It assists in supplying the knee joint.
