Osteochondritidies

Question 1

Define Perthe’s disease

Answer 1

• Idiopathic avascular necrosis of the capital femoral epiphysis of the developing femoral head
• This is followed by revascularisation and reossification over 18-36 months
• Mainly affects boys between 4-9 years

Catterall Staging

• Stage 1: clinical and histological features only
• Stage 2: sclerosis +/- cystic changes and preservation of the articular surface
• Stage 3: loss of structural integrity of the femoral head
• Stage 4: loss of acetabular integrity
• Don’t need to remember staging - just get that the more spherical, the better and the more mush, the worse

Question 2

Presentation of Perthe’s disease

Answer 2

1. Acute/ insidious onset limp
2. Hip pain, can be referred to groin, thigh or knee
3. Can have reduced ROM
4. May initially be mistaken for transient synovitis
5. It is bilateral in 10-20% of cases
6. Roll test – pt. supine, roll affected hip internally and externally -> guarding or spasm (esp. on internal)

RISK FACTORS: hyperactivity, short stature

DDx: osteomyelitis, transient synovitis, septic arthritis, hypercoag state (clotting. SCD, polycythaemia, malignancy)

Question 3

Investigations of Perthe’s disease

Answer 3

XR of both hips should be done (including frog views)

• Early signs include increased density in the femoral head
• Subsequently becomes fragmented and irregular

May see residual deformity

MRI- shows marrow changes

Bone scan- shows reduced perfusion to femoral head

Question 4

Management of Perthes

Answer 4

Principles of management: containing the femoral head within the acetabulum through the use of splints, braces or casts(surgery occasionally)

• < 6 years- observation and splints
• Older- surgical management with moderate results
• Operate on severe deformities

Individuals should be made non-weight bearing and referred to experienced paediatric orthopaedist

Acute Pain- supportive care with simple analgesia

Physical therapy- stretching the quadriceps and hamstrings, strengthening the quadriceps

Education about exacerbations and management

Question 5

Complication of Perthes

Answer 5

• Chronic pain
• Osteoarthritis

Prognosis

Most children have good outcome, most resolve with conservative management

Older children have a poorer prognosis

Question 6

Define Osgood-Schlatter Disease

Answer 6

This is osteochondritis of the tibial tubercle

• inflammation of cartilage or bone of the patellar tendon insertion at the knee

THINK SPORTY TEEN

Question 7

Causes of Osgood-Schlatter Disease

Answer 7

Caused by multiple small fractures within the apophysis of the tibial tuberosity at the inferior attachment of the patellar ligament

It is an overuse injury caused by repetitive strain and chronic avulsion of the apophysis of the tibial tubercle, which results in elevation

IMPORTANT: when assessing a painful knee, the hip should ALWAYS be examined because hip pain is often referred to the knee

Often affects adolescents who are physically active (particularly football and basketball)

Occurs in children 9-14 years who have undergone a rapid growth spurt

More commonly affects boys

Question 8

Presentation of Osgood-Schlatter Disease

Answer 8

Anterior knee pain after exercise, exacerbated by direct trauma, kneeling, running etc.

Pain is relieved by rest

Pain increases gradually over time from low-grade ache to pain causing limp/ impairs activity

Localised tenderness and swelling over the tibial tuberosity

Involvement is usually asymmetrical

Often hamstring tightness

Can be bilateral in 25-50% of cases

Question 9

Investigations for Osgood-Schlatter Disease

Answer 9

Diagnosis made by clinical examination

Examination

Basic observations

XR to exclude differentials in those with atypical features (e.g. erythema or warmth, pain at night)

Elevation of tubercle away from shaft

Irregularity, fragmentation, or increased density of tubercle

Calcification within or thickening of patellar tendon

Superficial ossicle in patellar tendon

Question 10

Management for Osgood-Schlatter Disease

Answer 10

NOTE: Conservative management is mainstay of treatment

**Pain Control **

1. Analgesia- paracetamol or NSAIDs
2. Intermittent application of ice packs over the tibial tuberosity (10-15 minutes up to 3 times per day, including after exercise)
3. Protective knee pads (may relieve pain when kneeling)
4. Reassure the patient and parents that this will resolve over time but may persist until the end of a growth spurt

**Continuation of activity **

1. Advise reducing sporting activity – intensity, frequency or duration
2. They could change the type of exercise to limit the amount of running and jumping requiring powerful quadriceps contraction
3. Playing with pain is permitted
4. As symptoms decrease, they can gradually increase their exercise levels

Physical therapy
1. Introduce low-impact quadricep exercises e.g. isometric quadriceps contractions, straight leg raises, cycling or swimming

ADVICE
* Victorian Paediatric Orthopaedic Network fact sheet on Osgood-Schlatter disease – has an explanation of the condition as well as instructions on some useful stretches
* Proper stretching before and after exercise may reduce symptoms

NOTE: most resolve with reduced activity and physiotherapy for quadriceps muscle strengthening, hamstring stretches and occasionally orthotics.

Question 11

Complications of Osgood-Schlatter Disease

Answer 11

Complications

• Persistent prominence of the tibial tubercle
• Persistent pain
• Rarely, genu recurvatum (back knee, hypertension of the knee)
• If not resolved after closure of growth plate, then may need corrective surgery

Prognosis
Benign, self-limiting disease

Symptoms resolve once growth plate ossified