Knee- Cartilage Injuries, Arthritis, Patello-Femoral Dysfunction Flashcards
The knee joint consists of what compartments?
Medial and lateral compartments of the tibiofemoral and patellofemoral joints
The surfaces of the knee joint are all covered with what?
Hyaline cartilage
Within which sub-joint of the knee are the menisci found?
Tibiofemoral joint
The menisci of the knee ensure congruence between where?
The concave femoral condyles and the flat tibial plateaus
What are the roles of the menisci?
Shock absorbers, and act to distribute load evenly
What is the role of the ACL?
Prevent abnormal internal rotation of the tibia
How is the ACL tested?
By assessing anterior translation of the tibia
What are the roles of the PCL?
Prevents hyperextension and anterior translation of the femur
How is the PCL tested?
By assessing posterior translation of the tibia
What is the role of the MCL?
Resist valgus stress
What are the roles of the LCL?
Resist varus stress and abnormal external rotation of the tibia
Most injuries of the knee joint can predispose to OA. What are some common predisposing injuries?
Joint instability, malalignment, ACL deficiency, meniscal tears
If you have gene varum, what type of knee OA will you have?
Medial compartment OA
If you have gene valgum, what type of knee OA will you have?
Lateral compartment OA
Knee joint instability will predispose to what type of knee OA?
Patellofemoral
What are some non-operative management options for knee joint OA?
Weight loss, stick, exercise, analgesics, activity modification
When are steroid injections used for knee OA?
Only for acute flare ups
When can an osteotomy of the proximal tibia be used as a treatment for knee OA?
Varus knees with isolated medial compartment OA (usually younger patients)
What is the aim of an osteotomy of the proximal tibia as a treatment for isolated medial compartment OA?
Shift the load to the lateral compartment. Useful for manual workers where a knee replacement would fail.
What are the disadvantages of an osteotomy for the treatment of isolated medial compartment OA?
There can sometimes be neuropathic pain after. Will only last 7-10 years and after this procedure a knee replacement would not be as successful
When should knee replacements be offered to those with knee arthritis?
In older patients with severe disability and conservative management is no longer effective
What is the difference between a total and partial knee replacement?
A total replacement resurfaces all 3 compartments while a partial replacement only resurfaces 1
If a knee replacement is successful, how long will it last?
15-20 years
What are some risks of knee replacement surgery?
Unexplained pain, stiffness, DVT/PE
Why should knee replacements not be used in younger patients?
Higher chance of requiring revision surgery later which then has a higher rate of failure
Who has unicompartmental knee replacement been proposed as a treatment for?
Patients with isolated medial or lateral compartment OA and also for younger patients
If failure occurs following a UKR, can a TKR be used?
Yes
Which ligament of the knee is usually excised in TKRs and which is also often sacrificed?
Usually always excised = ACL, often sacrificed = PCL
Ongoing pain and effusion after a knee injury warrants further investigation to look for what?
Cartilage defects
What investigations can be used to assess for cartilage damage?
X-ray, MRI, arthroscopy
Articular cartilage injuries can occur in response to trauma, or they can be atraumatic. Give some examples of atraumatic causes?
Osteochondritis dissicans, osteoarthritis, inflammatory arthritis
What type of cartilage injuries can heal and why?
Only full thickness injuries can heal and they are the only ones to receive a blood supply
During healing of cartilage injuries, what takes the role of articular cartilage?
Fibrocartilage (not as good as hyaline but does the job)
What is osteochondritis dissicans?
Part of the joint temporarily loses blood supply, which causes dead bone and cartilage to fragment off
Who does osteochondritis dissicans typically occur in?
Adolescents
How is osteochondritis dissicans treated?
Can heal or resolve spontaneously in kids, or it can be fixed/removed
How should acute injuries involving large osteochondral fractures with a substantial portion of bone be treated?
Fixed with pins
How should cartilage injuries from a non-weight bearing area or those with little bone attached be treated?
Arthroscopic removal
Cartilage repair surgeries will not work if what is already present?
Osteoarthritis showing radiographic changes, inflammatory arthritis or joint instability
If a child presents with knee pain, what should you always check for?
The hips for SUFE
What knee condition commonly occurs in people who are on their knees a lot?
Bursitis
What is Osgood-Schlatter’s disease?
Anterior knee pain in adolescents, will go away with time
What is an autograft?
Tissue from the patient
What is an allograft?
Tissue from a donor
How many bundles does the ACL have? How many are reconstructed?
2 bundles, 1 reconstructed
What is patello-femoral dysfunction?
Any disorder of the patellofemoral articulation, resulting in anterior knee pain
What conditions does patella-femoral dysfunction include?
Chondromalacia patellae, adolescent anterior knee pain, lateral patellar compression syndrome
What is chondromalacia patellae?
Softening of the hyaline cartilage
The quadriceps muscle pulls the patella in what direction?
Lateral
Patello-femoral dysfunction is commoner in who? Why?
Females (wider hips meaning more lateral pull of quadriceps) and adolescents (ligamentous laxity)
Apart from being female and adolescent, what are some other risk factors for patello-femoral dysfunction?
Joint hyper mobility, genu valgum, femoral neck anteversion
Patients with patello-femoral dysfunction tend to complain of what?
Anterior knee pain, worse going downhill, a grinding or clicking sensation, stiffness after prolonged sitting (pseudo locking)
What are the treatment options for patello-femoral dysfunction?
> 90% of cases resolve with physiotherapy, aimed at rebalancing the quadriceps muscles. Taping can alleviate symptoms. Surgery is a last resort.
