Session 5 Flashcards
(225 cards)
Describe the structures that form the knee joint, including the bones, ligaments, menisci, joint capsule & bursae
- The knee joint is a ? type synovial joint, which mainly allows for ?. It is formed by articulations between the ?
- The knee joint consists of two articulations:
- The ? joint is the weight-bearing joint of the knee.
- The patellofemoral joint allows the tendon of the ? to be inserted directly over the knee, increasing the efficiency of the muscle. Both joint surfaces are lined with hyaline cartilage, & enclosed within a single joint cavity.
- The patella is formed inside the tendon of the quadriceps femoris; its presence minimises ?
- Neurovascular supply to knee joint
- The medial & lateral menisci are fibrocartilage structures in the knee that serve two functions:
- They are C shaped, and attached at both ends to the ?
- The medial meniscus is fixed to the ? Any damage to the tibial collateral ligament results in ?
- How if the lateral meniscus different, why is this important?

- bicondylar, flexion and extension (& a small degree of medial & lateral rotation), patella, femur & tibia.
- Tibiofemoral – The medial & lateral condyles of the femur articulating with the tibia.
Patellofemoral – The anterior & distal part of the femur articulating with the patella.
- tibiofemoral
- quadriceps femoris (the main extensor of the knee)
- wear & tear on the tendon
- genicular anastomoses around the knee, which are supplied by the genicular branches of the femoral & popliteal arteries.
The nerve supply, according to Hilton’s law, is by the nerves which supply the muscles which cross the joint. These are the femoral, tibial & common fibular nerves.
- To deepen the articular surface of the tibia, thus increasing stability of the joint.
To act as shock absorbers.
- intercondylar area of the tibia
- Tibial collateral ligament & the joint capsule, tearing of the medial meniscus
- smaller & does not have any extra attachments, rendering it fairly mobile







- A bursa is
- There are 5 bursae found in the knee joint:
- synovial fluid filled sac, found between moving structures in a joint – with the aim of reducing wear and tear on those structures.
- Suprapatella bursa – This is an extension of the synovial cavity of the knee, located between the quadriceps femoris and the femur.
Subcutaneous Prepatella bursa – Found between the apex of the patella and the skin.
Infrapatella bursa – Split into deep and superficial. The deep bursa lies between the tibia and the patella ligament. The superficial lies between the patella ligament and the skin.
Semimembranosus bursa – Located posteriorly in the knee joint, between the semimembranosus muscle and the medial head of the gastrocnemius.

Give a detailed description of the ligaments associated with the knee joint and understand the role of each ligament in maintaining stability
The major ligaments in the knee joint are: (5) state origins & insertions
- Patellar ligament – A continuation of the quadriceps femoris tendon distal to the patella. It attaches to the tibial tuberosity.
- Collateral ligaments – These are two strap-like ligaments. They act to stabilise the hinge motion of the knee, preventing any medial or lateral movement
Tibial (medial) collateral ligament – A wide and flat ligament, found on the medial side of the joint. Proximally, it attaches to the medial epicondyle of the femur, distally it attaches to the medial surface of the tibia.
Fibular (lateral) collateral ligament – Thinner & rounder than the tibial collateral, this attaches proximally to the lateral epicondyle of the femur, distally it attaches to a depression on the lateral surface of the fibular head.
- Cruciate Ligaments – These two ligament connect the femur and the tibia. In doing so, they cross each other, hence the term ‘cruciate’ (Latin for like a cross)
Anterior cruciate ligament – attaches at the anterior intercondylar region of the tibia and ascends posteriorly to attach to the femur, in the intercondylar fossa. It prevents anterior dislocation of the tibia onto the femur.
Posterior cruciate ligament – attaches at the posterior intercondylar region of the tibia, and ascends anteriorly to attach to the femur in the intercondylar fossa. It prevents posterior dislocation of the tibia onto the femur.

Describe the movements of the knee joint & the muscles involved.
There are four main movements that the knee joint permits:
Extension: Produced by the quadriceps femoris, which inserts into the tibial tuberosity.
Flexion: Produced by the hamstrings, gracilis, sartorius & popliteus.
Lateral rotation: Produced by the biceps femoris.
Medial rotation: Produced by five muscles; semimembranosus, semitendinosus, gracilis, sartorius & popliteus.
NB: Lateral & medial rotation can only occur when the knee is flexed (if the knee is not flexed, the medial/lateral rotation occurs at the hip joint).
Fractures of the distal femur & proximal tibia (recognise on X-rays & MRI scans) LO
- Epidemiology
- Mechanism young patients
- Classification
- traditionally young patients but increasing in geriatric population
bimodal distribution: young, healthy males, elderly osteopenic females
periprosthetic fractures becoming more common
- high energy with significant displacement
older patients
low energy, often fall from standing, in osteoporotic bone, usually with less displacement
- Descriptive
supracondylar
intercondylar
OTA: 33
A: extraarticular
B: partial articular
portion of articular surface remains in continuity with shaft
33B3 is in coronal plane (Hoffa fragment)
C: complete articular
articular fragment separated from shaft
Patellar fractures
- In a patellar dislocation, the patella bone is displaced out of the ?
- It accounts for around 3% of knee injuries. Most dislocations occur ?, and are caused by ?
- These mechanisms of injury make patellar dislocation more common in individuals participating in sports such as: ?
Dislocations
- Patellar fractures usually result from ?
- They are more common in ?
- If the patella fractures into fragments, they will usually separate; the proximal fragment displaced ? by the ? & the distal fragment pulled ? by the ?
- patellofemoral groove
- laterally, high force impact on the patella or forceful sudden twisting of the knee
- football, rugby & ice hockey.
- direct trauma to the bone
- sudden contraction of the quadriceps muscle
- direct trauma to the bone
- males, & in the 20-50 age range
- superiorly, quadriceps tendon, inferiorly, patellar ligament

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Patella tendon rupture
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Patella tendon rupture
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Quadriceps rupture
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Patella fracture

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Patella dislocation
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PATELLAR DISLOCATION OSTEOCHONDRAL
APD can lead to osteochrodral injury osteochondral injury is an injury to the smooth surface on the end of bones, called articular cartilage (chondro), and the bone (osteo) underneath it
Meniscal injuries

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Meniscal injury
Collateral ligament injuries
- Injury to the collateral ligaments is the most common pathology affecting the knee joint. It is caused by ?
- Damage to the collateral ligaments can be assessed by asking the patient to ?
- If the tibial collateral ligament is damaged, it is more than likely that the ?
- What is the unhappy triad
- Force being applied to the side of the knee when the foot is placed on the ground
- medially rotate & laterally rotate the leg. Pain on medial rotation indicates damage to the medial ligament, pain on lateral rotation indicates damage to the lateral ligament.
Lateral collateral ligament (LCL)
Below are instructions to examine the right knee – change your hands for the left knee
- Extend the patient’s knee fully.
- Hold the patient’s ankle between your elbow and side.
- Place your right hand along the medial aspect of the knee.
- Place your left hand on the lower limb (e.g. calf or ankle).
- Push steadily outward with your right hand whilst applying an opposite force with the left.
- If the LCL is damaged your hand should detect the lateral aspect of the joint opening up.
Medial collateral ligament (MCL)
Below are instructions to examine the right knee – change your hands for the left knee
- Extend the patient’s knee fully.
- Hold the patient’s ankle between your elbow and side.
- Place your right hand along the lateral aspect of the knee.
- Place your left hand on the lower limb (e.g. calf or ankle).
- Push steadily inward with your right hand whilst applying an opposite force with the left.
- If the MCL is damaged your hand should detect the medial aspect of the joint opening up.
If after this assessment the knee appears stable you can further assess the collateral ligaments by repeating this test with the knee flexed at 30°. At this position, the cruciate ligament is not taught so minor collateral ligament laxity can be more easily detected.
With healthy collateral ligaments, there should be no abduction or adduction possible. If abduction/adduction is possible, it suggests laxity/rupture of the corresponding collateral ligament.
- medial meniscus is torn, due to their attachment.
- Due to the attachment of the medial collateral ligament to the medial meniscus, damage to the medial collateral can affect this important cartilaginous structure. A lateral force to an extended knee, such as a rugby tackle, can rupture the medial collateral ligament, damaging the medial meniscus in the process. The ACL is also affected, which completes the ‘unhappy triad’.
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Medial collateral ligament rupture
Anterior & posterior cruciate ligament injuries
- The anterior cruciate ligament (ACL) can be torn by ?
- To test for this, you can perform an ?
- The most common mechanism of posterior cruciate ligament (PCL) damage is the ?
- To test for PCL damage, perform the:
5.
- hyperextension of the knee joint
- large force to the back of the knee with the joint partly flexed
- hyperextension of the knee joint
- Anterior/Posterior drawer test
- Flex the patient’s knee to 90º
- Inspect for evidence of posterior sag as this can give a false positive anterior drawer sign
- Wrap your hands around the proximal tibia with your fingers around the back of the knee
- Sit on the patient’s lower leg to fix its position
- Position your thumbs over the tibial tuberosity
- Ask the patient to keep their legs as relaxed as possible (tense hamstrings can mask pathology).
- Pull the tibia anteriorly and feel for any anterior movement of the tibia on the femur – significant movement maysuggest anterior cruciate laxity/rupture
- Push the tibia posteriorly – significant movement may suggest posterior cruciate laxity/rupture
Lachman’s Test (most sensitive test for ACL rupture)
- Flex the patient’s leg to 30°
- Hold the lower leg with one hand with the thumb on the tibial tuberosity and the fingers on the calf
- With the other hand hold the thigh just above the patella
- Use the hand holding the lower leg to pull the tibia forward on the femur while the other hand stabilises the femur
Significant anterior movement of the tibia on the femur signifies anterior cruciate ligament laxity/rupture.
- ‘dashboard injury’ knee is flexed, & a large force is applied to the shins, pushing the tibia posteriorly. (This is often seen in car accidents, where the knee hits the dashboard.)
- hyperextension of the knee joint, or by damage to the upper part of the tibial tuberosity.
- ‘dashboard injury’ knee is flexed, & a large force is applied to the shins, pushing the tibia posteriorly. (This is often seen in car accidents, where the knee hits the dashboard.)
- Posterior draw test:
This is where the clinician holds the knee in flexed position, & pushes the shin posteriorly. If there is movement, the ligament has been torn.
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ACL rupture
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Tibial spine #
ACL attaches here
Treatment
• Autograft – Hamstrings
Patellar tendon
- Allograft
- Synthetic – poor results
- We can’t replicate the original ACL
More common
Semitendinosus & membranous
Housemaids knee
- What is it ?
- There are a number of different things that can cause housemaid’s knee:
- prepatellar bursitis (inflammation of a small fluid-filled sac (the bursa) in front of the patella)
- A sudden, one-off, injury to the knee
This might be, for example, a fall or direct blow on to the knee.
- Recurrent minor injury to the knee
Friction between patella and skin/ pressure when kneeling down
- Infection
Common in children, usually follows a cut, scratch or injury to the skin on the surface of the knee.
- Another inflammatory disease
E.g. RA increased risk of developing a bursitis. Rheumatoid arthritis is a form of arthritis that causes inflammation, pain and swelling of joints.



























































































































