MSK sessions 5-7 AND 10 Flashcards
What type of a joint is the articulation between the ilium and the sacrum?
Plane synovial joint -
Allows for little movement (gliding movements may occur)
This stability is important for standing, walking and running on 2 legs.
The 2 pubic bones articulate with one another at the pubic symphysis. What type of a joint is this?
Cartilaginous joint
Type 2 - hyaline and fibrocartilage
The hip bone is made up of 3 bones that are originally separated by cartilage but fuse together by adulthood. These are…
Ilium
Ischium
Pubis
Where does the femur articulate with the hip bone?
Head of the femur articulates with hip bone at the acetabulum.
The greater trochanter is the point of the hip and the attachment site for…
Several gluteal muscles (abductors of the thigh at the hip joint)
The lesser trochanter is an attachment site for…
The ilipsoas tendon - a strong flexor of the thigh at the hip
Which bone is the weight-bearing bone of the leg?
Tibia
Which tarsal bone articulates with bones of the leg?
Talus
What does talus articulate with?
Trochlea of talus —> Tibia and fibula
Head of talus —> navicular
Inferiorly —> calcaneus
Which tarsal bone is the ankle bone?
Talus
Which tarsal bone is the heel bone?
Calcaneus
Where is the mid-inguinal point?
Where is the mid-point of the inguinal ligament?
Mid-inguinal point
Halfway between ASIS and pubic symphysis
Mid-point of the inguinal ligament
Halfway between ASIS and pubic tubercle
Where is true leg length measured from?
ASIS to the medial malleolus at the ankle joint
Is the linea aspera on the anterior or posterior surface of the femur?
Posterior
What does the fibula articulate with?
Articulates proximally and distally with the tibia
Articulates distally with the talus at the talocrural (ankle) joint
What bones make up the pelvic girdle?
Hip bones - ilium ischium pubis
Sacrum
Coccyx
Which muscles secure the pelvis prevent pelvic drop of the contralateral limb during locomotion?
Gluteal medius and gluteal minimus
As the pirformis travels through the greater sciatic foramen, it divides the gluteal region into an inferior and superior part. Which nerve supplies the muscles in the gluteal region above the pirformis and which nerve supplies the muscles below the pirformis?
Which nerve enters the gluteal region directly inferior to the piriformis?
Above - superior gluteal nerve
Below - inferior gluteal nerve
The sciatic nerve enters the gluteal region directly inferior to the piriformis. Therefore, hypertrophy of this muscle can cause sciatic nerve compression.
Which is on the anterior surface of the femur and which is on the posterior surface?
Intertrochanteric line
Intertrochanteric crest
Intertrochanteric line = anterior
Intertrochanteric crest = posterior
What is the common action of all of the superior gluteal muscles except gluteus maximus?
Medial rotation of hip
Abduction of hip
What is the action of all of the deep gluteal muscles?
Lateral rotation of hip
Abduction of hip (except quadratic femoris)
Which muscle is the main extensor and lateral rotator of the hip?
Gluteus maximus
Where do the quadriceps femoris insert?
Patella and tibial tuberosity via patellar ligament
Where does iliopsoas insert?
Lesser trochanter
All of the quadriceps come from the femur except…
Rectus femoris (2 heads) from:
Anterior inferior iliac spine
Ilium just superior to acetabulum
Which anterior muscles of the thigh flex at the hip joint?
Rectus femoris
Pectineus
Sartorius
Iliopsoas
All of the adductor of the thigh originate at the…
Pubis
Adductor magnus adductor part originates at inferior rami of pubis and rami of ischium
All of the adductors of the medial thigh insert at…
Linea aspera
The hamstring part of adductor magnus and the hamstrings in the posterior thigh originate at…
Ischial tuberosity
Obturator internus and obturator externus insert in roughly the same places.
True or false.
True - but obturator internus is on the lateral side of the hip bone and obturator externus is on the medial side of the hip bone
both laterally rotate hip
The only muscle in the medial thigh that flexes at the knee is…
Gracilis
All muscles in the anterior thigh are innervated by…
Femoral nerve (pectineus is also innervated by obturator nerve)
All muscles in medial thigh are innervated by…
Obturator nerve
Which muscles of the thigh insert at the medial tibia?
Gracilis
Sartorius
Semitendinosus
Whhat is the action of all of the muscles in the posterior thigh?
Flex at knee and extend at hip
Which muscle of the posterior thigh inserts at the head of the fibula?
Biceps femoris
Muscles in the posterior compartment of the thigh are innervated by…
Branches of the sciatic nerve
Which artery provides most of the blood supply to the head and neck of the femur?
Medial femoral circumflex
The femoral artery becomes the popliteal artery after passing through the adductor hiatus. The adductor hiatus is a space in which of the muscles of the thigh?
Adductor magnus
What are the name of the arteries that supply the knee joint?
Genicular branches
The fibular artery arises from which artery in the leg?
Posterior tibial artery
A pulmonary embolism can develop as a result of deep vein thrombosis in the lower limb. What type of shock would this lead to?
Mechanical shock
Varicose veins arise due to…
Incompetent valves within a vein. The valves normally prevent backflow within the lumen, if incompetent blood leaks back into superficial veins leading to dilated and tortuous veins.
Where does the femoral artery originate and from which artery?
External iliac artery (terminal branch of abdominal aorta) when it crosses under the inguinal ligament and enters the femoral triangle.
What are the main branches that arise from the femoral artery within the femoral triangle?
Perforating branches - perforate adductor magnus contributing to the supply of muscles in the medial and posterior thigh
Lateral femoral circumflex artery - wraps around the anterior lateral side of the femur supplying lateral thigh muscles
Medial femoral circumflex artery - wraps around the posterior side of the femur supplying the head and neck of the femur
In a fracture of the femoral neck, which artery is easily damaged and what can this lead to?
Medial femoral circumflex artery
Avascular necrosis of the femur head
After exiting the femoral triangle, the femoral artery continues down the anterior surface of the thigh via the adductor canal. During its descent the artery supplies the anterior thigh muscles. On entering the adductor hiatus, the femoral artery is now known as…
The popliteal artery
Where can the femoral artery be easily accessed?
Femoral artery is located superficially within the femoral triangle so is easy to access here.
There are three main pulse points in the lower limb:
Femoral
Popliteal
Dorsalis pedis
Where can they be found?
Femoral pulse - at the mid-inguinal point (midway between ASIS and pubis synthesis) as it enters the femoral triangle
Popliteal - difficult to find as it is found deep in the popliteal fossa, flex leg to relax fascia and make it easier to find
Dorsalis pedis - dorsum of foot lateral to extensor hallucinating longus tendon
An aneurysm of the popliteal artery within the popliteal fossa is most likely to compress which nerve?
How would this present?
Tibial nerve - this nerve is found centrally in the popliteal fossa
Weakened or absent plantarflexion
Parasthesia of foot and posterolateral leg
Once the popliteal vein has entered the thigh via the adductor canal, it becomes the…
Femoral vein
When does the femoral vein become the external iliac vein?
When it leaves the thigh passing under the inguinal ligament
Describe the distribution of the great saphenous vein
Origin:
Dorsal venous arch of the foot, dorsal vein of great toe
Distribution:
Ascends up the medial side of the leg, passing anteriorly to the medial malleolus at the ankle and posteriorly to the medial condolences at the knee.
Drains into the femoral vein, immediately inferior to the inguinal ligament.
Which superficial vein ascends up the medial side of the leg?
Great saphenous vein
An obvious palpable pulsation in the popliteal fossa indicates what…
Popliteal aneurysm
What does the presence of a femoral pulse indicate?
Where is it palpated?
Blood is reaching the lower extremity
Mid-inguinal point - halfway between ASIS and pubis synthesis
Why might access to the femoral artery be required?
Where is it accessed?
Procedure such as a coronary angiography - femoral artery can be catheterised with a long, thin tube. Tube navigated to external iliac artery, common iliac artery, aorta and to the coronary vessels. Dye can be injected into the coronary vessels and any wall thickening or blockages can be viewed on an x-ray.
Femoral artery is located superficially within femoral triangle so is easy to access here.
What is a hernia?
A condition in which part of an organ is displaced and protrudes trough the wall of the cavity containing it.
What is a femoral hernia?
Part of the bowel pushes into the femoral canal, underneath the inguinal ligament.
This manifests as a lump in the area of the femoral triangle - usually requires surgical intervention to treat.
What is the main function of the empty space in the femoral triangle?
Allow the femoral vein to distend when venous return is high
What can be found at the mid-point of the inguinal ligament?
Femoral nerve
Which vein enters the femoral triangle to drain into the femoral vein?
Great saphenous vein
What are the borders of the femoral triangle?
BORDERS
• Superior border
Inguinal ligament - ligament that runs from ASIS to pubis tubercle
• Lateral border
Medial border of sartorius
• Medial border
Medial border of adductor longus
FLOOR
Pectineus, iliopsoas, adductor longus
ROOF
Fascia lata
What are the contents of the femoral triangle, lateral to medial?
CONTENTS - lateral to medial
• N - Femoral nerve
motor: anterior compartment of thigh
Sensory: leg and foot
• A - Femoral artery (in femoral sheath)
majority of arterial supply to lower limb
• V - Femoral vein (in femoral sheath)
great saphenous vein drains into the femoral vein within the triangle
• E- empty space - important as it allows the veins and lymph vessels to distend so they can cope with different levels of flow
• L - (lymph) Femoral canal (in femoral sheath)
structure which contains deep lymph nodes and vessels
A lump is found inferolateral to the pubic tubercle in a femal patient. What could be the cause and why should this be treated immediately?
Femoral hernia- part of the small intestine protrudes through the femoral ring. This type of herniation is more common in women due to their wider bony pelvis.
The borders of the femoral canal are tough, and not extendible. This can compress the hernia, interfering with its blood supply. A hernia with a compromised blood supply is known as a strangulated hernia.
What are the boundaries of the popliteal fossa?
BORDERS
• Superomedial border
Semimembranosus
• Superolateral border
Biceps femoris
• Inferomedial border
Medial head of gastrocnemius
• Inferolateral border
Lateral head of gastrocnemius and plantaris
FLOOR
Posterior surface of the knee joint capsule
Posterior surface of femur
ROOF
Popliteal fascia (continuous with fascia lata of leg)
Skin
What are the contents of the popliteal fossa?
Medial to lateral:
Most deep:
• Popliteal artery
Popliteal vein - deep saphenous vein enters and drains here
Most superficially:
• Tibial nerve
• Common fibular nerve - follows biceps femoris tendon along lateral margin
These are both branches of the sciatic nerve
What is a baker’s cyst?
Inflammation and swelling of the semimembranosus bursa.
Usually arises in conjunction with arthritis of the knee.
Rupture can produce symptoms similar to deep vein thrombosis.
What type of a joint is the knee joint?
Hinge type synovial joint
What are the articulating surfaces in the knee joint?
-tibiofemoral
Medial and lateral condyles of the femur with medial and lateral condyles of the tibia
-patellofemoral
Anterior and distal part of the femur with patella
Both joints are enclosed within a single joint cavity
The patella is a sesamoid bone. Which tendon is it formed inside of?
Tendon of quadriceps femoris
What stabilises the knee joint?
• Strength and actions of surrounding muscles and tendons
◦ Most important
◦ Quadriceps femoris
• Ligaments connecting femur and tibia
What are the menisci?
Structure:
• Fibrocartilage structures
• C shaped
• Attached at both ends to the intercondylar area of the tibia
Function:
• Deepen the articular surface of the tibia to increase stability of the joint
• Shock absorber
Any damage to the tibial collateral ligament results in damage of which structure?
Tearing of medial meniscus
Where is the prepatellar bursa located?
Between apex of the patella and skin
Which bursa lies between quadriceps femoris and the femur?
Suprapatella bursa
Which bursa is located posteriorly in the knee joint between semimembranosus and the medial head of gastrocnemius?
Semimembranosus bursa
Where are the deep and superficial infrapatellar bursae found?
deep bursa - between tibia and patella ligament
Superficial - between patella ligament and the skin
The patellar ligament is a continuation of which tendon?
Quadriceps femoris tendon
What is the function of the collateral ligaments in the knee?
Prevents medial or lateral rotation
Force applied to the lateral aspect of a fixed knee is likely to damage which ligament?
Medial collateral ligament
What is the function of the anterior cruciate ligament?
Prevents anterior dislocation of the tibia onto the femur
Which ligament prevents posterior dislocation of the tibia onto the femur?
Posterior cruciate ligament
How can the anterior cruciate ligament be torn?
Hyperextension of the knee joint
Application of a large force to the back of the knee with the join partially flexed
A dashboard injury is likely to cause damage to which ligament?
Dashboard injury - large force applied to the shins when the knee is flexed pushing the tibia posteriorly.
Likely to damage posterior cruciate ligament
What is housemaid’s knee?
Inflammation of the prepatella bursa (located between the apex of the patella and the skin)
Cause: kneeling on knees
What is clergyman’s knee?
Inflammation of the infrapatella bursa
(Deep bursa- between tibia and patellar ligament
Superficial bursa-between patella ligament and skin)
Cause: kneeling on hard surfaces for a long time
What is the unhappy triad?
A lateral force to an extended knee ruptures the medial collateral ligament
Damage to the medial collateral ligament tears the medial meniscus
The anterior cruciate ligament is also damaged
What type of a joint is the hip joint?
Ball and socket synovial joint
What are the articulating surfaces of the hip joint?
Pelvic acetabulum
Head of femur
The ligaments of the hip joints can be classified as intracapsular and extracapsular. What are they?
Intracapsular:
-ligament of head of femur
Extracapsular:
- iliofemoral ligament
- pubofemoral ligament
- ischiofemoral ligament
Describe the location and function of the iliofemoral ligament.
Y shaped appearance
AIIS to intertrochanteric line of femur
Function: prevents hyperextension of the hip joint
Describe the location and function of the pubofemoral ligament.
Triangular shape
Superior pubic rami to intertrochanteric line of femur
Function: prevents excessive abduction and extension
Describe the location and function of the ischiofemoral ligament.
Spiral orientation
Body of ischium to greater trochanter of femur
Function: prevents excessive extension
Which arteries supply the hip joint?
- lateral and medial circumflex humeral arteries (mainly medial)
- artery to head of femur
- superior/inferior gluteal arteries
What stabilises the hip joint?
- acetabulum - deep and encompasses nearly all of femoral head
- acetabular labrum - fibrocartilaginous collar increases depth of acetabulum
- extracapsular ligaments and thickened fibrous joint - ligaments have a unique spiral orientation so are tighter when joint extends
- muscles and ligaments work in a reciprocal fashion
How do the ligaments and muscles of the hip joint work in a reciprocal fashion to stabilise it?
- Anteriorly, where the ligaments are strongest, the medial flexors are fewer and weaker (iliopsoas, rectus femoris, pectineus, sartorius)
- Posteriorly, where the ligaments are weakest, the medial rotators are greater in number and stronger - the effectively pull the head of the femur into the acetabulum (gluteus medius, gluteus minimus, semitendinosus, semimembranosus)
Where is the joint capsule of the hip weakest and hence what kind of acquired dislocation is most common/
Inferior and posterior part of the joint capsule
Posterior dislocation most common - affected limb is shortened and medially rotated.
In a posterior dislocation of the hip, which nerve is at greatest risk of injury?
Sciatic nerve as it runs posteriorly to the hip joint
What type of a joint is the ankle joint?
Synovial hinge joint
What are the articulating surfaces of the talocrural joint?
• Bracket shaped socket - mortise
◦ Tibia and fibula are bound together by strong tibiofibular ligaments
◦ Produces a bracket shaped socket
◦ Covered in articular hyaline cartilage
• Wedge-shaped talus
◦ Body of talus fits into into the mortise
◦ Talus is wider anteriorly and thinner posteriorly
How many separate ligaments is the medial ligament of the ankle composed of?
Four
What is the function of the medial ligament of the ankle?
Resists over eversion of the foot
How many seperate ligaments is the lateral ligament of the ankle made up of?
Three
What is the function of the lateral ligament of the ankle?
Resists over inversion of the foot
Arterial supply to the ankle is via…
malleolar branches of the:
• Anterior tibial artery
• Posterior tibial artery
• Fibular artery
Innervation of the ankle is via…
- Tibial nerve
* Deep fibular nerves
What is an ankle sprain?
When does it usually occur?
Partial or complete tears in the ligaments of the ankle joint.
Usually occurs in a plantarflexed weight-bearing foot which is excessively inverted.
Why is the lateral ligament of the ankle more likely to be damaged than the medial ligament in an ankle sprain in a plantarflexed, weight-bearing foot which is excessively inverted?
Lateral ligament is weaker than medial ligament
Lateral ligament resists inversion
What is a Pott’s fracture?
bimalleolar fracture (medial and lateral malleoli)
OR
Trimalleolar fracture (medial and lateral malleoli, distal tibia)
What should be considered in a fracture of the ankle joint?
Ligament damage which would not show up on an x-ray as the ankle joint and associated ligaments function as a ‘ring’ so usually breaks in 2 places.
What type of joint is the subtalar joint?
Plane synovial joint
What are the articulating surfaces of the subtalar joint?
- Posterior talar articular surface - Inferior surface of the body of the talus
- Posterior calcaneal articular facet - superior surface of the calcaneus
Which ligament is the most important in providing stability to the subtalar joint?
Interosseous talocalcaneal ligament
Falling onto the heel from a height is likely to fracture which bone and disrupt which joint?
Calcaneus
Subtalar joint - likely to become arthritic
Which 2 nerves of the lumbar plexus have the same nerve roots?
Femoral nerve
Obturator nerve
L2 L3 L4
What are the roots of the ilioinguinal nerve?
What are its motor and sensory functions?
Roots: L1
Mixed nerve
Motor functions:
• Internal oblique abdominis
• Transversus abdominis
Sensory functions:
• Skin on upper middle thigh
• In males, skin over root of penis and anterior scrotum
• In females, skin over mons pubis and labia majora
What are the roots of the genitofemoral nerve?
What its sensory and motor functions?
Roots: L1 L2
Mixed nerve
Motor functions:
• Genital branch innervates the cremasteric muscle
Sensory functions:
• In males, genital branch innervates skin of anterior scrotum
• In females, genital branch innervates skin over mons pubis and labia majora
• Femoral branch innervates the skin on upper anterior thigh
What are the roots of the lateral cutaneous nerve of the thigh?
What is its functions?
Roots:
L2 L3
Sensory nerve
Sensory functions:
• Innervates the anterior and lateral thigh down to the level of the knee
What are the roots of the obturator nerve?
What are its functions?
Mixed nerve
Motor functions: Medial thigh muscles that adduct the hip joint (except obturator externus) • Obturator externus - laterally rotates • Pectineus • Adductor longus • Adductor brevis • Adductor magnus • Gracilis
Sensory function:
• Skin over medial thigh
The obturator nerve can be damaged during surgery involving the pelvis or abdomen. What would symptoms of this be?
Numbness and parasthesia on the medial aspect of the thigh
Weakness in adduction of the thigh
Posture and gait problems due to the loss of adduction
Where can anaesthetic be injected in an obturator nerve block?
Inferior to the pubic tubercle and lateral to the tendon of the adductor longus muscle
What are the roots of the femoral nerve?
What are its functions?
Roots:
L2 L3 L4
Mixed nerve
Motor functions: Anterior muscles of thigh that flex the hip joint and extend the knee joint • Pectineus • Sartorius • Illiacus • Quadriceps femoris
Sensory functions:
• Skin on anterior thigh
• Skin on medial leg
The saphenous vein is often stripped in individuals with varicose veins. What important structure could this damage and what would this present as?
Saphenous nerve
Parasthesia or complete loss of sensation on the medial side of the lower leg
What are the roots of the sacral plexus?
Anterior rami of S1 S2 S3 S4
Roots are joined by L4 and L5 to form lumbosacral trunk
What are the roots of the superior gluteal nerve?
What are its functions?
L4 L5 S1
Motor nerve
Motor functions:
• Gluteus medius
• Gluteus minimus
• Tensor fascia lata
What are the roots of the inferior gluteal nerve and what are its functions?
Roots:
L5 S1 S2
Motor nerve
Motor functions:
• Gluteus maximus
What are the roots of the sciatic nerve and what are its functions?
Roots:
L4 L5 S1 S2 S3
Mixed nerve
Motor functions: Tibial portion: • Posterior compartment of the thigh (hamstrings + hamstring part of adductor magnus - short head of biceps femoris) • Posterior compartment of leg • Sole of foot Fibular portion: • Short head of biceps femoris • Anterior compartment of leg • Lateral compartment of leg
Sensory functions: Tibial portion: • Skin on posterolateral foot • Medial surfaces of foot • Sole of foot Common fibular portion: • Skin on anterolateral surface of leg • Dorsal foot
What are the roots of the posterior femoral cutaneous nerve and what are its functions?
Roots:
S1 S2 S3
Sensory nerve
Sensory functions:
• Posterior surface of thigh and leg
• Skin on the perineum
Anatomical course:
• Leaves the pelvis via the greater sciatic foramen
• Enters gluteal region inferiorly to the piriformis muscle
• Descends deep to the gluteus maximus and runs down the back of the thigh to the knee
What are the roots of the pudendal nerve and what are its functions?
Roots:
S2 S3 S4
Keeps the poo of the floor
Mixed nerve
Motor functions: • Skeletal muscles in perineum • External urethral sphincter • Anal sphincter • Levator ani
Sensory functions:
• Penis
• Clitoris
• Most of the skin on the perineum
What are the nerves of the lumbar plexus?
Ilioinguinal Genitofemoral Lateral cutaneous nerve of the thigh Femoral nerve Obturator nerve
What are the nerves of the sacral plexus?
Superior gluteal nerve Inferior gluteal nerve Sciatic nerve and its divisions Posterior femoral cutaneous nerve Pudendal nerve (not taught in MSK: to be covered in the reproduction unit later in the course
What are the contents of the adductor canal?
Femoral artery
Femoral vein
Saphenous nerve (largest cutaneous branch of the femoral nerve)
What are the borders of the adductor canal?
Anterior
Sartorius
Lateral
Vastus medialis
Posterior
Adductor longus and adductor magnus
Which muscle unscrews the femur to begin flexion?
Popliteus
Origin: posterior surface of proximal tibia
Insertion: lateral condyle of femur and menisci of knee
Innervation: tibial nerve
What is the extensor mechanism?
Quadriceps Quadriceps tendon Patella Patellar ligament Tibial tuberosity
If there is a problem with extension, consider damage to any of these structures.
The collateral ligaments provide a secondary restraint during internal or external rotation?
External rotation
The cruciate ligaments provide a secondary restraint during internal or external rotation?
Internal rotation
What is the function of the menisci of the knee?
- deepen the articular surface of the tibia to increase stability of the joint
- shock absorber
- load transmission
- nutrition for articular cartilage
When the hip is extended, the femur tends to externally rotate. Which muscles are required to neutralise this effect?
Medial rotators
Gluteus medius and gluteus minimus
Is lateral or medial rotation of the hip a stronger movement?
Lateral rotation
All of the deep gluteal muscles act to laterally rotate
Which side of the body do you use a stick when your hip is hurt?
Contralateral
Where are the most common sites for osteoarthritis?
Hips
Knees
Small joints of the hand
What are the risk factors for osteoarthritis?
Obesity Past injury in a joint Occupational factors Genetics - females Old age
What are the signs and symptoms of arthritis?
Joint pain Crepitis Joint deformity Osteophytes Joint stiffness
How do patients often present with osteoarthritis of the hip joint?
Joint stiffness Pain of hip, gluteal and groin areas radiating to the knee Mechanical pain Limited walking function Limited and painful internal rotation Leg length discrepancy
Which movement of the hip joint is usually the first to be impaired in osteoarthritis?
First internal rotation
State some differences between rheumatoid arthritis and osteoarthritis under the following headings: Speed of onset Distribution Joints affected Stiffness Systemic symptoms
Age of onset
RA- any age , OA- usually elderly
Speed of onset
RA- rapid, OA- slow over years
Distribution
RA- symmetrical polyarthritis, OA- initially symmetrical monoarthritis which develops into polyarthritis
Joints affected
RA- small joints of hands and feet, OA- weight bearing joints
Stiffness
RA- worse in mornings>1 hour, OA- end of day <1 hour
Systemic symptoms
RA- fatigue, fever, night sweats, OA- none
What is the difference between primary and secondary osteoarthritis?
Primary - aetiology is multifactorial, involving both genetic and environmental factors. Prevalence increases with age
Secondary - aetiology is known
Eg.
Trauma - involving the joint surfaces or causing a deformity which puts greater pressure on part of the joint
Developmental dysplasia of the hip
Infection: septic arthritis, brucella, TB
Metabolic: gout
Haematologic: haemophilia
Is joint ankylosis seen in osteoarthritis?
No
How does osteoarthritis change the structure of articular cartilage?
Increased tissue swelling
Change in colour
Cartilage fibrillation - local surface disorganisation involving a splitting of the superficial layers of cartilage
Cartilage erosion down to the subchondral bone
What happens to the chondrocytes in articular cartilage affected by osteoarthritis?
The cartilage damage causes chondrocytes cloning in an attempt to restore the articular surface. (Normal adult chondocytes are fully differentiated and do not proliferate).
Which bones make the medial arch of the foot?
The medial arch is made up by the calcaneus, the talus, the navicular, the three cuneiformss and the first, second and third metatarsals
How is weight transmitted through the foot?
Tibia—>
Talus—>
Calcaneus and other bones of foot
Describe the structures involved in propulsion.
Progression:
Heel - lateral border- metatarsal heads - toes
Power: Gastrocnemius/soleus complex (achilles tendon) Toe flexors (flexor digitorum longus, flexor hallucis longus)
Which nerve arteries and tendons are found in the posterior part of the ankle?
Medial to lateral
Tibialis posterior Flexor digitorum longus Artery - posterior tibial artery Vein - posterior tibial vein Nerve - tibial nerve Flexor hallucis longus
Which artery enters the foot dorsally?
Anterior tibial artery
Which nerve provides sensory innervation to most of the sole of the foot?
Tibial nerve
Which 5 nerves enter the foot?
Tibial nerve
Superficial fibular nerve
Deep fibular nerve
Sural nerve (formed by the union of branches from both tibial and common fibular nerve)
Saphenous nerve (branch of femoral nerve)
Which nerve provides sensory innervation to most of the dorsum of the foot?
Superior fibular nerve
What is the difference between true locking of the knee and pseudolocking?
• true locking caused by a mechanical block where something gets stuck inside the joint, preventing movement – meniscal tear or loose body
• Pseudo locking – pain + muscle spasm
Where are the safe sites for intramuscular injection in the gluteal region?
The anatomical course of the sciatic nerve must be considered when administering intramuscular injections into the gluteal region. The region can be divided into quadrants using 2 lines, marked by bony landmarks.
One line descends vertically from the highest point of the iliac crest.
The horizontal line passes half way between the highest point of the iliac crest and the ischial tuberosity
The sciatic nerve passes through the lower medial quadrant. To avoid damaging the sciatic nerve, intramuscular injections are given only in the upper lateral quadrant of the gluteal region.
What is Tredelenburg Gait?
Tilted pelvis is compensated by shifts in the upper body over the affected hip during the period of a single leg stance. The combination of tilted pelvis and upper body shifts results in this classic gait where the leg is swung.
Caused by loss of function of gluteal medius and minimus
Patient presents with difficulty walking. While observing his gait, you see that he leans towards the left side while he walks. When the patient lifts his foot off the ground, his left hip dips downwards.
Diagnosis?
Trendelenburg gait
Superior gluteal nerve injury
Or
Gluteus medius and gluteus minimus injury
What does valgus and varus mean?
Valgus: deviation of the distal limb away from the midline
Varus: deviation of the distal limb towards the midline
If someone has ruptured their Achilles tendon, why might they still be able to plantarflex?
Plantaris attachment has not been damaged
Where do the posterior tibial artery and tibial nerve run in the posterior leg in relation to the muscles in the posterior compartment of the leg?
The muscles in the calf (i.e. posterior compartment of the leg) are organised into superficial and deep groups. The neurovascular structures (posterior tibial artery and tibial nerve) run between the two muscle groups. These muscles plantar flex the ankle and cause inversion of the foot.
What is the order of tendons and neurovascular structures that pass from the posterior compartment of the leg into the foot in relation to the medial malleolus?
Tom - Tibialis posterior Dick - Flexor digitorum longus And - posterior tibial artery Very - posterior tibial vein Nervous - tibial nerve Harry - flexor hallucis longus
Are the saphenous veins superficial or deep veins?
Superficial veins
What type of gait would damage to the common fibular nerve lead to?
Footdrop
The common fibular nerve wraps around the head of fibula, so blunt trauma or fracture here can lead to foot drop.
The deep fibular nerve innervates the muscles in the anterior compartment of the leg. These muscles dorsiflex the foot, which is required during the swing phase to clear the toes away from the ground.
If the deep fibular nerve is damaged, then the foot cannot be dorsiflexed, and drags along the ground during the swing phase. To try and dorsiflex the foot during the swing phase, the patient may evert the foot in a sudden motion, called an ‘eversion flick’.
High steppage gait is where the hip is excessively flexed to prevent themselves from falling over their feet.
What are the phases of walking?
Stance phase - 60% of gait cycle
Swing phase - 40% of gait cycle
Which muscles are active in the heel strike stage of the stance phase?
Gluteus maximus - decelerates lower limb
Quadriceps femoris - keeps the leg extended at the knee and hip
Anterior compartment of leg - maintains dorsiflexion, positions the heel for the strike
Which muscles are active in the support stage of the stance phase?
Quadriceps femoris - keeps the leg extended, accepting the weight of the body
Foot inverters and everters - contract in a balanced manner to stabilise the foot
Gluteus minimus, medius and tensor fascia lata- abducts the contralateral lower limb keeping the pelvis level by counteracting the imbalance created from having most of the body weight on one leg
Which muscles are involved in the toe off stage of the stance phase?
Hamstring muscles - extends leg at the hip
Quadriceps femoris - maintains the extended position of the knee
Posterior compartment of the leg - plantar flexes the ankle
Which muscles are involved in the leg lift stage of the swing phase?
Iliopsoas and rectus femoris - flex the lower limb at the hip, driving the knee forwards
Hamstring muscles - flex the lower limb at the knee
Anterior compartment of the leg - dorsiflexes the ankle
Which muscles are involved in the swing stage of the swing phase where the leg is propelled forward?
Iliopsoas and rectus femoris - flex the hip resisting gravity as it tries to pull the leg down
Quadriceps femoris - extends the knee positioning the foot for landing
Anterior compartment of the leg - maintains ankle dorsiflexion so that the heel is in place for landing
What are the differences in the gait cycle when running and walking?
Instead of there being a double support phase, which happens when walking, there is a period of double float where both feet are off the ground.
Describe what happens in Trendelenburg gait.
In normal gait, when the left leg is lifted, the right leg takes the entire weight. The gluteus medius and minimus contract on the contralateral side to prevent the pelvis from dropping on the affected side.
• In Trendelenburg gait, when the unaffected side is in swing phase, the pelvis drops on the unaffected side as the contralateral abductors cannot stabilise the hip. The supporting leg is on the affected side.
• To compensate for this the upper trunk leans over the side of the lesion so that the centre of gravity is restored.
When do you see antalgic gait and what are its features?
Cause: Painful leg (knee, ankle, hip)
What happens? • One of the legs is painful when it is in the stance phase • Therefore, the affected leg has ◦ A short stance phase ◦ Lack of body weight shifted to it ◦ Longer swing phase • The other leg has ◦ A short swing phase • This produces an uneven gait
Which patients present with hemiplegic gait?
Hemi-brain injury:
Stroke
Trauma
Cerebral palsy
Features of a patients gait: On one leg: • Flexed upper limb • Extended lower limb • Plantarflexion of the ankle • Circumduction of the affected to accommodate for the increased length (swinging it round to clear toes off the floor to put affected leg in the midline)
What type of gait is this?
Hemiplegic gait
Patients gait is described as: Scissoring On both legs: • Tight muscle groups ◦ Psoas, adductors, hamstrings, calf • Ankle is plantarflexed • Forefoot initial contact (calf muscles tight)
What type of gait is this and what is the likely cause?
Diplegic gait
Neuromuscular disorders eg. Cerebral palsy
Patient presents with footdrop and a high stoppage gait. What nerve is likely to be damaged?
Deep fibular nerve or common fibular nerve
What can cause the femoral shaft to be fractured and what type of fracture is this?
How does the patient present?
What are the complications of this fracture?
Require a lot of force (car accident, crushing)
Spiral fracture
Leg shortening due to overriding of the bony fragments as they are pulled by their attached muscles.
- surrounding soft tissues may be damaged
- risk of femoral artery and nerve damage
In a road traffic accident, a pedestrians knee hit the bumper of a car. What bone is likely to be fractured?
Bumper of car is just about the right height to break the proximal end (particularly the tibial condyles) during a road traffic accident
Can lead to issues of the knee joint as the cruciate and tibial collateral ligaments attach to the bone near this point/the articular surface is damaged
Fractures of the tibial shaft are the most common site for open fractures.
True or false?
True.
The anterior surface of the tibia is subcutaneous so the skin is likely to be perforated and blood vessels are likely to be torn causing external bleeding.
What fracture can overeversion lead to?
- Overeversion of the ankle forces the talus against the medial malleolus, leading to a fracture of the medial malleolus
- This is accompanied with a fracture of the lateral malleolus normally, constituting a bimalleolar fracture
- Disrupts walking due to their roles in ankle stability
In which direction are patellas likely to be dislocated?
Laterally
Dislocations are uncommon.
Which menisci of the knee is most commonly torn and how?
Medial secondary/tertiary to the unhappy triad but can be caused by rapid rotation of the knee while the foot is planted on the ground.
Which collateral ligament is most likely to be torn in the knee?
Medial collateral ligament
A blow to the lateral side of the knee is likely to damage which collateral ligament?
Blow to the lateral side of the knee stretches the medial collateral as it tries to resist the opening of the knee on the medial side, so medial collateral ligament.
What is likely to cause anterior cruciate ligament damage?
Hyperextension of the knee
Force applied to a partly flexed knee
What is the unhappy triad?
Tearing of the anterior cruciate ligament leads to medial movement of the femur.
Medial movement of the femur tears the medial collateral ligament.
The medial collateral ligament is attached to the medial meniscus so this tears.
If the posterior cruciate ligament is torn, which way can the tibia be moved?
Posteriorly
What is housemaid’s knee?
Prepatella bursititis
As with all bursitis, it’s a result of excessive repetitive friction between the patella and skin where the prepatella bursa lies, from too much kneeling at one position. Treat with avoidance of that activity.
What is Clergyman’s knee?
As with all bursitis, it’s a result of excessive repetitive friction between the tibial tuberosity and the skin where the superficial infrapatellar bursa lies, from too much kneeling at one position (but a different position to prepatellar bursitis). Treat with avoidance of that activity!
What is tendinosis?
Non-inflammatory degenerative condition with collagen degeneration in the tendon due to repetitive overloading.
Can lead to tendonitis (inflammation of a tendon)
Patient presents with a hot swollen knee.
What could be the cause?
- Septic arthritis
Bactaraemia can lead to septic arthritis of the knee. Often due to Staphylococcus aureus or Group B streptococcus.
This breaks down the cartilage
Patient may present with a hot swollen knee
- Gout/pseudogout
Uric acid (gout) or calcium pyrophosphate (pseudogout) deposition in knee joint.
Patient may present with a hot swollen knee.
- Could be something else…
Patient has a stab wound their buttock. What important structure is likely to be damaged?
Sciatic nerve, inferior gluteal nerve, artery and vein
Deep to gluteus maximus and superficial to the deep gluteal muscles, below piriformis
Superior gluteal nerve, artery and vein
Deep to gluteus maximus and superficial to the deep muscles, above piriformis
A posterior dislocation of the hip is likely to damage which nerve?
Femoral head compresses sciatic nerve
When looking at an x-ray how can you tell if a fracture of the hip joint is intracapsular or extracapsular?
Intracapsular —> The entire femoral neck is enclosed in the capsule. If you can see the neck fractured, it is intracapsular
Extracapsular—> Head and neck intact. This is basically a proximal femoral fracture
Describe the complications of an intracapsular fracture of the femur.
- Medial femoral circumflex artery damaged by an intracapsular fracture, only blood supply remaining is a branch of the obturator artery heading to the head of femur – not sufficient to perfuse the bone
- Leads to avascular necrosis of the femoral head
What is the common clinical appearance of the limb after an intracapsular fracture?
Shortened leg
Laterally rotated leg
(Distal fragment pulled upwards and laterally)
Are intracapsular or extracapsular fractures typically seen in older patients and women?
Intracapsular fracture:
• Typically seen in older patients (reduced bone density) and women (primary osteoporosis)
Extracapsular fracture:
• Typically seen in younger, more active patients
Is the femoral head at risk of avascular necrosis in an extracapsular fracture?
No, the medial femoral circumflex artery is not damaged
How does the limb present clinically in an extracapsular fracture of the femur?
Shorted
Laterally rotated
(Distal fragment pulled upwards and rotated laterally)
Same clinical presentation in intracapsular and extracapsular fractures.
How would gait change in avulsion of the greater trochanter?
Avulsion of the greater trochanter:
• Not very common, requires a huge amount of force ie car accident
• As it is the attachment of gluteus medius and minimus, it leads to these being unable to perform their function effectively
• This leads to a positive Trendelenberg’s test
In which direction is acquired dislocation of the hip joint most common?
Almost always posteriorly as this is where the joint is weakest (only the ischiofemoral ligament and a few muscles compared to the stronger protection anteriorly)
How would the limb present clinically in a posterior dislocation of the hip joint?
Shortened
Medially rotated
What is congenital dislocation of the hip?
The hip joint does not develop properly in utero
Some abnormality of either the acetabulum )not behind deep enough) or the neck of the femur (incorrect angle) means the neonate is born with a dislocated hip or a hip that dislocates very easily.
What are the clinical features of congenital dislocation of the hip joint?
- limited abduction of the hip joint
- limb length discrepancy (affected limb is shorter)
- medially rotated limb
- positive trendelenburg test
30-50 year old patient
Playing football
Felt as if he was kicked on the back of the heel
Pain in posterior ankle.
What could be the cause?
Achilles tendon rupture
Examination:
- see if you can see a gap between two tendon edges (would show if patient presents early)
- Thompson test - tell patient to kneel on chair. Squeeze cal and the tendon should move showing there is continuity between gastrocnemius, soleus and the tendon. (Cannot see gap in patients who present late as area fills with blood)
What is the difference between claw toe and hammer toe?
Claw toe
Presentation:
-hyperextension of the metatarsophalangeal joint
-flexion of the proximal interphalangeal joint
-flexion of distal interphalangeal joint
-affects the lateral four toes at the same time
Hammer toe
Presentation:
-extension of the metacarpophalangeal joint
-flexion of the proximal interphalangeal joint
-extension of the distal interphalangeal joint
-can affect any toe on your feet
What is flat foot?
Loss of medial longitudinal arch in foot. Medial arch and lateral arch at the same level.
If the intrinsic ligaments supporting the medial arch are loose or degenerated (eg. Deltoid ligament), then the talus will move inferomedially slightly, which collapses the arch, causing flat feet. This leads to some lateral deviation when the foot bears weight. Causes of ligament degeneration include old age, rapid weight gain, rapid undertaking of exercise etc.
Children up until at least the age of 3 have a large subcutaneous fat pad that hides the arch so don’t diagnose flat feet in them!
What is a sprained ankle?
An ankle sprain refers to partial or complete tears in the ligaments of the ankle joint.
The lateral ligaments are more likely to be damaged as they are weaker and resists inversion.
The anterior talofibular ligament is the lateral ligament most at risk of irreversible damaged as it is flatter and thinner than others.
Excessive eversion causes a metatarsal fracture. Which metatarsal is this likely to be?
5th metatarsal
Fibularis brevis avulses its attachment
What is Pott’s fracture-dislocation?
Bimalleolar (medial and lateral malleoli)
Trimalleolar (medial, lateral and distal malleoli)
Results from excessive eversion.
- excessive eversion pulls on the medial ligaments, producing an avulsion fracture of the medial malleolus
- talus moves laterally, breaking off the lateral malleolus
- tibia is then forced anteriorly, shearing off the distal and posterior part against the talus
What are bunions?
Hallux valgus
Bony lumpy deformity at the base of the big toe.
The big toe is deviated laterally
Sesamoids may no longer be sitting under the first metatarsal head
Which joints are commonly affected by osteoarthritis in the foot?
1st metatarsalphalangeal joint and ankle
What advice should you give diabetics about their feet and why?
They must inspect their feet daily as diabetes causes loss of protective sensation in the foot which leads to severe infections. They are vasculocompromised and immunosuppressed so are more susceptible to infection.
What is charcot arthropathy?
Loss of pain sensation in diabetics leads to destruction of joints - massive deformity and bone loss
Describe what happens in neuropraxia (Class I of seddon classification).
CLASS I = Neurapraxia - conduction block
When? Pressure on a nerve for a sustained period of time
What happens?
This is the mildest type of nerve injury and is a temporary physiological block of conduction in the affected axons without loss of axonal continuity. The endoneurium, perineurium and epineurium are also intact and there is no Wallerian degeneration. Conduction is intact in the distal segment and proximal segment of the nerve but no conduction occurs across the area of injury.
Recovery?
Hence, there is sensory and motor dysfunction distal to the site of injury. Full recovery of the nerve conduction will occur over a period of days to weeks.
Describe what happens in axonotmesis (class II of seddon classification).
CLASS II = Axonotmesis - axons divided
What happens?
This involves loss of continuity of the axons and their myelin sheath, but the endoneurium, perineurium and epineurium are preserved. Wallerian degeneration occurs within 3-4 days distal to the site of injury.
Regeneration?
However, axonal regeneration then occurs and recovery is usually possible without surgical intervention. Axonal regeneration proceeds at a rate of 1-4 mm/day; hence the time to recovery depends on the distance from the site of injury to the target organ.
Describe what happens in neurotmesis (Class III of Seddon classification).
CLASS III = Neurotmesis - nerve divided
What happens?
This is either a partial or complete division of the axons, endoneurium, perineurium and epineurium of a nerve fibre. Wallerian degeneration occurs distal to the site of injury within 3-4 days and the sensory, motor and autonomic defects are severe.
Regeneration?
Surgical intervention is always necessary as, even in an incomplete division, the deposition of scar tissue between the divided fascicles precludes regeneration.
What causes neuropathies?
• Injury ◦ stretch of a nerve ◦ complete division • Extrinsic pressures ◦ Tumour ◦ Abcess • Medical conditions ◦ Diabetes ◦ Alcohol excess ◦ Drugs • Other rare causes ◦ Nerve tumours
What is a neuroma?
Swelling of a nerve where it has been injured if the nerve cannot regenerate - painful
Patient has a paracentral prolapsed disc at L4/L5. How would they present?
• L5 Sciatica
SENSATION: Lateral Thigh, lateral calf, dorsum of foot
MOTOR: Great toe extension, ankle inversion, hip abduction
Patient has a paracentral prolapsed disc at L5/S1. How would they present?
• S1 Sciatica
SENSATION: Posterior Thigh, Posterior Calf, Heel, Sole of Foot
MOTOR: Ankle plantarflexion, ankle eversion, hip extension
Patient has a far lateral disc prolapse at L4/L5. How would the patient present?
• L4 Sciatica
SENSATION: Anterior thigh, Anterior knee, medial shin
MOTOR: Ankle dorsiflexion
Patient has a far lateral disc prolapse at L5/S1. How would they present?
• L5 Sciatica
SENSATION: Lateral Thigh, lateral calf, dorsum of foot
MOTOR: Great toe extension, ankle inversion, hip abduction
The most common cause of sciatica is a prolapsed vertebral disc.
Name another cause of sciatica.
Piriformis syndrome - compression of the sciatic nerve by hypertrophied piriformis muscle
Sciatica symptoms not originating from spinal roots/ spinal disc compression but due to the pirformis muscle which is posterior to the sciatic nerve
What is meralgia paraesthetica?
Entrapment of the lateral cutaneous nerve of the thigh
What can cause meralgia parasthesia?
Anterior superior iliac spine is easily palpated. The lateral cutaneous nerve of the thigh passes immediately medial to this so is easily compressed as it passes through the inguinal ligament or as it pierces the fascia lata by things such as
• Tight clothing
• Tool belt
• Obesity - compression by abdominal fat
• Pregnancy
How would femoral nerve injury in the femoral triangle present?
SENSORY:
Loss of saphenous nerve - medial leg
Medial cutaneous nerve of thigh - anterior thigh
MOTOR:
Rectus femoris, iliacus - hip flexion
Quadriceps - knee extension
How would tibial nerve injury in the popliteal fossa present?
MOTOR:
Flexor hallucis longus and flexor digitorum ongus - flexion of toes and plantarflexion
Tibiais posterior - plantarflexion and inversion —> CALCONEOVALGUS FOOT
SENSATION:
Tibial nerve - sole of foot, inferior aspect of toes and nail beds
Is the common fibular nerve prone to injury and why?
Common fibular nerve hooks around the head of the fibular- therefore any injury to the fibular head can result in damage to this nerve
When might the superficial fibular nerve be injured?
- Ankle surgery via a a lateral approach (ankle fracture-fractured lateral malleolus)
- Ankle arthroscopy portal placement
How would a patient present with a superficial fibular nerve injury?
MOTOR:
Fibularis longus and brevis - ankle eversion
SENSORY:
Dorsum of foot
Anterolateral calf
How would a patient present with a deep fibular nerve injury?
MOTOR:
Anterior leg muscles: tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius - dorsiflexion and toe extension—> FOOT DROP
SENSORY:
1st web space
What are the common causes of saphenous nerve injury?
- Stripping of long saphenous vein varicosities
* Removal of vein for vein graft
How would a saphenous nerve injury present?
SENSATION:
Medial leg
When might the sural nerve be damaged?
Surgery to lesser saphenous vein
How would a patient present with a sural nerve injury?
SENSATION:
Lateral side of leg and posterior leg
Lateral foot
