RCGP_update_1

Question 1

What are common causes of acute painful knee? (+/- swelling)

Answer 1

Traumatic haemarthrosis.Gout.ACL rupture.PCL rupture.Torn meniscus.Suspected fracture.Traumatic synovitis or exacerbation of osteoarthritis.

Question 2

Is ACL or PCL rupture more common? By what mechanism would they occur?

Answer 2

ACL is more common.ACL usually occurs after non-contact deceleration. There may be a hyperextension and an audible “pop”.PCL may occur following a blow to the anterior proximal tibia with the knee flexed.

Question 3

What might a gradual accumulation of fluid in the knee suggest?

Answer 3

Could be an effusion caused by a traumatic synovitis (e.g., a cartilage injury) or to an exacerbation of osteoarthritis. Also could be a meniscal tear.

Question 4

What are the causes of torn meniscus in the knee? How are these tears different?

Answer 4

Trauma or degeneration. Degeneration can account for a torn meniscus with minimal trauma in someone middle aged or older.A traumatic tear in a normal meniscus usually results form a twisting strain applied to a flexed, weight bearing knee. Usually results in a longitudinal or radial tear.A normal force on a degenerative meniscus usually causes a horizontal tear on the posterior half of the meniscus.

Question 5

What is locking of the knee? What is it caused by?

Answer 5

A blocking of extension, usually caused by a displaced torn off portion of meniscus that gets lodged between the femur and the tibia in the centre of the joint. AKA a bucket handle tear.

Question 6

What are the clinical features of a meniscal tear of the knee?

Answer 6

Often a sports related injury with a twisting of the knee.Immediate pain and loss of ability to play further sports.Swelling may follow hours or days later.Eases with rest but then recurs with trivial twisting/injury.Medial meniscal tear well localised to anterio-medial joint line. (More frequent).Lateral meniscal tear is more diffuse and poorly localised.Knee may lock out.Knee may be held in slight flexion.An effusion may be present.Extension is often limited, while flexion is not reduced.Can test using McMurry’s test or Apley’s

Question 7

What may cause locking of the knee?

Answer 7

Meniscal tear.Osteochondritis dessicans.Loose bodies within the joint - fracture of the patella, fracture of an osteophyte.Medial shelf syndrome.

Question 8

What Ix for suspected meniscal tear?

Answer 8

First line is usually MRI - gold standard and good for diagnosing meniscal tear and ACL rupture.Arthroscopy gives the definitive diagnosis.Plain XR is useful in differentials, e.g., excluding bony pathologies.Does NOT seem to be a role for USS!

Question 9

What are the Rx options for meniscal tear?

Answer 9

Conservative.Partial meniscectomy.Complete meniscectomy.Meniscal repair.Meniscal transplant.Locked knees need emergency Rx - MRI and arthroscopy.

Question 10

What are the features of conservative management for meniscal tear, and for whom should it be considered?

Answer 10

Should be considered for ALL patients, regardless whether other options are also being considered.RICE. NSAIDS, paracetamol.Activity modification, PT.Restrict deep flexion and twisting for 6/52.If not better after 6/52 –> refer for arthroscopy

Question 11

Is partial or complete meniscal repair more common? Why? When indicated?

Answer 11

Complete is not common - it often results in accelerated cartilage loss & OA.Partial is indicated when repair not possible e.g., in unstable tears (repair not possible).

Question 12

Where are meniscal repairs usually carried out? What is the recovery like after surgery?

Answer 12

Usually in the outer third of the meniscus - because this is the most vascularised. The inner, avascular zone is repaired rarely.Patients are kept partially or non-weight bearing for several weeks. The healing takes about 4 weeks after which the patients are usually asymptomatic. Postoperative PT useful!

Question 13

What factors have a more favourable outcome for meniscal tear repair?

Answer 13

Repair within 8 weeks of injury.Concurrent ACL repair.Lateral meniscal tear.A peripheral tearLength of tear <30 yrs.

Question 14

Other than the common causes of a painful knee +/- swelling, what are important causes of swollen knee not to miss?

Answer 14

-Septic arthritis - systemic symptoms, often in high risk patient (e.g., IVDU) or prosthetic joints.-Reactive arthritis - low grade fever, conjunctivitis, urethritis. Risk factors for STI’s-Malignancy - may be weight loss, night sweats.-Connective tissue disease - may be other features e.g., rashes, iritis.

Question 15

What are different causes of medial knee pain by age group?

Answer 15

9-15yrs: medial meniscal tear; medial collateral ligament injury; osteochondritis dessecans.15-30: as for 9-15; osteochondral injury or defect; per anserinus bursitis.30-60: as for 15-30; spontaneous osteonecrosis of the knee; medial OA.60+: medial OA; spontaneous osteonecrosis of the knee.

Question 16

What is osteochondritis dessecans? Where does it most frequently occur? What is the cause?

Answer 16

It is dissecting of a small portion of articular cartilage and the subjacent bone, resulting in an avascular segment. Lateral aspect of medial femoral condyle is most frequent site.Cause is usually idiopathic, but may be caused by one large trauma or repeated micro trauma, or vascular insufficiency.Osteochondritis dissecans predisposes the individual to osteoarthritis.

Question 17

What are characteristic features of osteochondritis dissecans? How to Ix?

Answer 17

Vague intermittent pain, morning stiffness, swelling/effusion, sometime locking (also giving way). May be quadriceps wasting and focal bony tenderness.Ix by XR (both knees) - may demonstrate osteochondral lesion or a loose body in the knee joint. Specific views (e.g., weight bearing, tunnel views, lateral etc) may be required.

Question 18

What is Rx for osteochondritis dissecans?

Answer 18

If the fragment is in position (stable lesions) then the treatment consists of conservative methods (e.g.- weight-relief and restriction of activity) . In a child there may be complete healing, although this may take up to 2 years. if the fragment becomes detached and symptomatic then it should be pinned or removed.

Question 19

What are the causes of anterior knee pain in different age groups?

Answer 19

9-15: Chondromalacia; Osgood-Shlatter disease.15-30: Chondromalacia, patellar maltracking (and dislocation); jumper’s knee; fat pad inflammation; saphenous nerve irritation; bursitis.30-60: As for 15-30; osteochondral defect.60+: Patellofemoral joint arthritis

Question 20

What is chondromalacia? What are the clinical features?

Answer 20

Softening of the articular cartilage of the patella usually as the result of indirect trauma, eg, unaccustomed sporting activity.It is a significant cause of anterior knee pain in teenage girls.The presentation is with retropatellar pain that is worse on rising from prolonged sitting or when using stairs (especially walking down a flight of stairs).On examination there may be fluid detectable behind the knee. The posterior surface of the patella can be felt if the patella is pushed sideways, and this is often tender. If the patella is pressed against the femur and then moved then this causes pain. This condition may be accompanied by crepitus.

Question 21

What is the treatment of chondromalacia? And the prognosis?

Answer 21

The treatment of chondromalacia patellae usually involves avoidance of repetitive knee bending and physical recreation. On occasion there is patellar misalignment that requires surgical intervention. If there is severe softening and degeneration of the articular surface, patellectomy is an option: this reduces the risk of future osteoarthritis. Alternatives include immobilisation in plaster and scraping the articular surface at arthroscopy. Generally the condition resolves by 30.

Question 22

What is Osgood-Shlatter’s disease?

Answer 22

An overuse syndrome associated with physical exertion before skeletal maturity. It is a traction apophysitis caused by multiple avulsion fractures. Occurs around the pubertal growth spurt when the quadriceps have enlarged but the apophysis has not yet fused to tibia. Especially seen in young athletes who take part in sports with repetitive knee flexion and forced extension. More common in males, but affects females earlier.

Question 23

What is the presentation of Osgood-Shlatter’s disease?

Answer 23

Often patients complain of pain, tenderness and a lump over the tibial tubercle. The pain may wax and wane, follow activities such as squatting, jumping, walking up or down stairs, or forceful contractions of the quadriceps muscle. Bilateral in 20-30%.

Question 24

How is Osgood-Shlatter’s diagnosed? Is there a role for XR?

Answer 24

The disease is diagnosed clinically and routine radiographs are not required unless the patient presents with unilateral and/or severe and persistent pain or there is marked swelling (to exclude bony tumors or infections).

Question 25

In children, if Osgood-Shlatter’s is suspected, what else should be examined and why?

Answer 25

The hip should also be examined, as the pain may be referred, e.g., from a SUFE.

Question 26

What is the Rx and prognosis of Osgood-Shlatter’s disease?

Answer 26

This is usually a self limiting condition and resolves with skeletal maturity.Conservative therapy is successful in most patients which usually include rest from painful activities, applying ice packs and analgesic medications; local muscle stretching and strengthening (quadriceps); corticosteroid injections are NOT recommended. A total embargo on sport for up to 6 months with gradual return afterwards may be needed in some patients.Majority of the patients return to full activity in two to three weeks. An infrapatellar strap can be used for symptomatic relief during activity (about six to eight weeks).

Question 27

What are the causes of posterior knee pain by age group?

Answer 27

9-15: tumour; popliteus pathology; sciatic or tibial nerve irritation; medial or lateral meniscal tear.30-60: Baker’s cyst; popliteal aneurism; sciatic referred pain.

Question 28

What are the causes of lateral knee pain by age group?

Answer 28

9-15: Osteochondral defect; discoid lateral meniscus15-30: As for 9-15; lateral meniscal tear; lateral collateral ligament injury; popliteus syndrome; iliotibial band syndrome.30-60: As for 15-30; lateral OA; lateral patellofemoral joint arthritis.60+: Patellofemoral joint arthritis, lateral OA.

Question 29

What is medial shelf syndrome? How to diagnose? How to Rx?

Answer 29

This is a syndrome characterised by superomedial knee pain and a history of brief locking of the joint. It is caused by inflammation of the synovial fold above the medial meniscus.Diagnosis requires arthroscopy, and it is treated with rest, NSAIDS, steroid injection or arthroscopic division of the synovial fold.

Question 30

What is runner’s knee also know as? What part of the knee hurts? What is it? What other sportspeople get it?

Answer 30

Iliotibial band syndrome. The lateral knee is affected, proximal to the joint line, worse during exercise.. It is an overuse syndrome, cyclists, skiers, football players, and weight lifters also get it.

Question 31

What predisposes to iliotibial band syndrome?

Answer 31

Excessive mileage. running on crowned roads, sudden increase in mileage, caws feet, genu varum, tibia varum, rearfoot and/or forefoot varus, and leg length discrepancy.

Question 32

How to diagnose and manage iliotibial band syndrome?

Answer 32

Diagnosis of ITB friction syndrome is based on clinical examinationPatients typically present with tenderness over the lateral femoral epicondyle and report a sharp, burning pain when the practitioner presses on the lateral epicondyle during knee flexion and extension.Pain is particularly acute when the knee is at 30 degrees of flexion.Non-operative surgical treatment consists of reduction and/or changing of activity, correction of structural abnormalities. cooling of the inflamed area, administration of anti-inflammatory medication, steroid injections and physical therapy including stretching. Surgery can be considered after unsuccessful non-surgical treatment.

Question 33

In an acute swollen knee, when might particular blood tests be useful?

Answer 33

ESR/CRP – if infection or inflammation suspected.Vitamin D – those at high risk of deficiency.Alkaline phosphatase – if underlying malignancy suspected.Calcium – if hypo/hyperparathyroidism suspected.Auto-antibodies (e.g. Rheumatoid factor).Uric acid – normal levels do not exclude gout; serum urate levels are normal in about 50% of flares.

Question 34

When should a joint aspiration not be performed?

Answer 34

If tumour is suspected.

Question 35

What are indications for a joint aspiration?

Answer 35

If suspected of having a crystal, inflammatory, or septic arthritis; also for symptomatic relief in haemarthrosis.

Question 36

What should aspirated fluid from a joint be examined for?

Answer 36

Macroscopically; and microscopically for bacteria (gram stain, culture), crystals, leukocytes.

Question 37

What are the criteria for diagnosing OA without an XR?

Answer 37

-Over 45.-Chronic (more than 3 months).-Morning stiffness lasts no more than 30 minutes.-An alternative diagnosis is unlikely.However patients with suspected OA who have a worsening or persisting effusion are likely to need further Ix.

Question 38

What is the purpose of a skyline view when XR of knee?

Answer 38

It is view of the patella to assess patelo-femoral joint.

Question 39

If degree of degeneration in knee joint is questioned, what view is needed?

Answer 39

Weight bearing, A-P, lateral, and skyline.

Question 40

Is XR more helpful in gout or pseudogout?

Answer 40

Pseudogout - features of chondrocalcinosis.In gout, XR not that helpful - might show joint erosions and cysts.

Question 41

When is an MRI knee helpful?

Answer 41

Advisable in patients 60 year olds with normal X-rays or if a specific pathology is considered.May be misleading in over 65 years as pathology demonstrated may not be cause of pain.Often requested in secondary care.

Question 42

Within what time-frames should patient’s with knee problems be referred to secondary care?

Answer 42

Suspected septic arthritis - same day.Hx of trauma or onset of swelling within 12 hours (if e.g., fracture or haemarthrosis suspected) - same day.Suspected inflammatory arthritis - 2 weeks.Suspected bone neoplasm - urgent / 2ww.

Question 43

What are indications for referral in knee pain/swelling?

Answer 43

Any RED FLAGS (Night pain. Weight loss. Previous malignancy. Fevers. Suspected haemarthrosis).Persistent pain.Previous surgery (joint replacement/ligament reconstruction).Multiple pathology involving spine/hip/knee (might be inflammatory arthropathy).

Question 44

For whom is surgical management of ACL tear usually considered?

Answer 44

Under 20.BMI <30.Those per suing contact sports and twisting sports.Autograft reconstruction is usually more favoured, especially in young athletes.