Common Musculoskeletal Problems: Knee Flashcards
List the causes of pain in the knee
- Trauma and overuse
- Periarticular problems
a. Anterior and medial knee pain
b. Meniscal tears
c. Cruciate ligament tears - Acute monoarthritis
a. Gout
b. Pseudogout
c. Reiter’s disease
d. Septic arthritis - Oligoarthritis - spondyloarthritis
- Polyarticular - RA
- Popliteal cyst / ruptures cyst
- Osteochondritis dessicans
- Hypermobility syndrome
- Referred from hip
Which collateral ligament of the knee is most commonly affected and how does it present?
Medial collateral ligament
- Pain at insertion into upper medial tibia
- Worse on standing or stressing
What is anserine bursitis and who does it most commonly affect?
Inflammation of anserine bursa just below the pes anserinus.
- Pain and localised tenderness
- 2-3 cm below posteromedial joint line in upper tibia
Affects:
- Obese women, often with valgus deformities
- Breast-stroke swimmers
How is medial knee pain treated?
- Physiotherapy
2. Local steroid injection
What age group are most commonly affected by anterior knee pain?
Adolescents
What is ‘anterior knee pain syndrome’ and how is it treated?
- No specific cause found
- Pain settle with time
Advise:
- Isometric quadriceps exercise
- Avoid heels
- Reassurance
What are the causes of anterior knee pain?
- Pre- and infrapatellar bursitis
- Osgood-Schlatter disease
- Patellar tendinopathy
- Abnormal patellar tracking
- Hypermobility of joints
- Idiopathic (‘anterior knee pain syndrome’)
What is ‘housemaid’s knee’ and what is the main complication?
Pre- or infrapatellar bursitis caused by unaccustomed kneeling 1. Local pain 2. Tenderness 3. Fluctuant swelling Rx: avoidance and steroid injection Complcation: septic bursitis
A 14 year old patient presents with pain and swelling over the tibial tubercle. He is an enthusiastic sportsman. What is the most likely diagnosis?
Osgood-Schlatter disease - a traction apophysitis of the patellar tendon, uncommon over age 16
What is ‘jumper’s knee’?
Patellar tendonitis - an enthesitis at the patellar end of the tendon due to overuse of extensor mechanism; typically basketball or volleyball players.
Rx: RICE
How is chondromalacia patellae diagnosed?
Arthroscopically - retropatellar cartilage is fibrillated
When is surgery indicated for chondromalacia patellae?
- Patellar misalignment
2. Recurrent patellar dislocation in adolescent girls
A patient presents with medial knee pain, joint-line tenderness and a locked flexed knee. The patient reports swelling within a few hours. What is the most likely diagnosis?
Meniscal tear
How would you manage a suspected meniscal tear?
- Immediately apply ice
- MRI demonstrates tear
- Operative Rx:
- Early arthroscopic repair or trimming of torn meniscus - Physiotherapy - quads
A patient presents with knee pain and immediate swelling following an injury in dance class. The anterior draw test is positive. What is the most likely diagnosis?
Anterior cruciate ligament tear
How would you manage a suspected cruciate ligament tear?
- MRI
2. Reconstructive surgery in young active adults
What is a common complication of cruciate ligament tear?
Secondary OA of the knee
What is osteochondritis dissecans and what are the risk factors?
Detachment of a fragment of bone and its detached cartilage by shearing - most commonly from lateral aspect of medial femoral condyle.
- Age - adolescents/young adults
- Male gender
- Trauma
- Heredity
What symptoms might a patient with osteochondritis dissecans present with?
- Aching pain after activity
2. Locking or giving way - if fragment becomes loose
How would you manage a patient with suspected osteochondritis dissecans?
Ix: MRI (most sensitive) or tunnel-view X-ray
Undisplaced Rx:
- Rest and physic (quads)
Displaced Rx:
- Arthroscopy repair or removal of loose fragments
What is tunnel-view X-ray and when is it used?
Patient is prone with the knee flexed at 40 deg (PA)
- View of intercondylar notch, articular condylar surfaces and origin of popliteus
- Osteochondritis Dissecans
Which part of the knee does osteochondritis dissecans most commonly affect?
Lateral aspect of medial femoral condyle
- Similar lesion affecting lateral condyle occurs in older people
What does SONK stand for and how does it present?
Spontaneous osteonecrosis of the knee
- Local pain +/- effusion, popliteal cyst
- Bone marrow changes on MRI or SPECT-CT
How would you manage spontaneous osteonecrosis of the knee?
- Avoid weight-bearing
- Pamidronate IV
- Knee replacement - if bone infarction
What is a complication of SONK?
Bone infarction - requires surgical replacement
What 3 symptoms are caused by an effusion of the knee?
- Swelling
- Stiffness
- Pain
+/- warmth (inflammatory)
What are the common causes of an acute inflammatory monoarthritis?
- Inflammatory arthritides (RA, spondyloarthropathies)
- Septic arthritis
- Gout (middle-aged males)
- Pseudogout (elderly)
An elderly patient complains of severe knee pain without obvious inflammation. You aspirate a clear, viscous effusion. What is the most likely diagnosis?
Osteoarthritis of the knee
A patient presents with a suspected knee effusion. What sign would you expect to find on examination?
- Pain
- Stiffness
- Swelling on both sides of patellar and supra patellar pouch
- Patellar tap sign
- Bulge sign
A patient presents with a swollen, stiff and painful knee. What investigations are indicated?
- Blood tests
- Aspiration
- Examination of effusion
How is joint aspiration performed?
- Inject local anaesthetic
- Attempt to aspirate it as you advance the needle - If fluid is obtained, change syringe and aspirate fully
- Examine fluid
- Clear or slightly cloudy: steroid injection
- Yellow: send to microbiology
What are the 2 main causes of haemarthrosis of the knee?
- Trauma
- Meniscal, cruciate or synovial lining tear - Clotting/bleeding disorder
- Haemophilia
- Sickle cell
- Von Willebrand’s disease
What complication occurs in approx. 5% of patients with a knee effusion?
Popliteal (Baker’s) cyst
What is a Baker’s cyst and how is it best seen?
A swelling in the popliteal fossa caused by fluid from the knee joint protruding to the back of the knee via connection to the semimembranosus bursa. Best seen and felt in popliteal fossa with patient standing.
Is a popliteal cyst a true cyst?
No - there is one-way communication with the synovial sac; allows effusions of the knee to flow into bursa but not back.
What is a complication of a popliteal cyst?
Rupture
- Sudden and severe pain, swelling and tenderness of the upper calf
- Ankle oedema
- Reduced size of knee effusion
A patient presents with a history of knee problems and sudden onset of pain and tenderness high in the calf. What is the most likely diagnosis and how is it treated? What is the differential?
Ruptured popliteal cyst Rx: - Analgesics or NSAIDs - Rest with leg elevated - Aspiration and injection with steroids into knee joint
DVT - excluded with US
