Definition: Idiopathic avascular necrosis of the capital femoral epiphysis in children.
Etiology: Still not sure.
Recent work suggests that the femoral head changes may be due to venous infarction in children with abnormal thrombolysis due to deficiency in thrombolysin.
Pathology of PERTHES’ DISEASE:
3 stages taking about 2 years.
1. Stage of necrosis.
2. Stage of fragmentation:
- Dead bony trabeculae may fracture by body weight.
- Epiphysis may become collapsed and fragmented.
3. Stage of regeneration:
New blood vessels enter the epiphysis and new bone is laid down on the dead trabeculae.
- The femoral head may retain its normal rounded shape until the stage of regeneration and the patient will remain asymptomatic
- The femoral head may become deformed and the patient will develop O.A. in middle age.
2- Effect of age at onset on outcome:
The older the child at onset, the worse the outcome.
- Onset < 6 years: do well with little treatment.
- Onset 6-8 years: do well with treatment.
- Onset > 9 years: may or may not respond to treatment.
This is due to the ability of the mostly cartilaginous femoral head of a young child to remodel, compared with the limited remodeling of the bony femoral head of an older child.
Clinical Diagnosis of PERTHES’ DISEASE
- Age : Most common age are 5-10 years.
- Sex : More common in boys (ratio 4:1).
- Side : 90% unilateral.
- History: Insidious onset of limping and slight intermittent pain in the hip or knee.
Examination of PERTHES’ DISEASE:
a) Early Case (Irritable hip):
All hip movements are diminished and painful (muscle spasm).
b) Established Case:
– Limitation of abduction and internal rotation.
– Mild shortening due to collapse of femoral head.
Radiographic Diagnosis: (AP & Lat views of hip)
A) Radiographic Sequences:
1) Early Case:
Initially may appear normal and then will show increased density of capital femoral epiphysis.
2) Late Case:
– Epiphysis : Flattening, fragmentation, and epiphyseal extrusion.
– Metaphysis: Cystic changes and broadening.
B) Radiographic Classification:
There are many classifications, but the current favorite classifications are:
1. Catterall Classification:
- Group I : Anterior part of epiphysis involved with no sequestrum formation.
- Group II : Anterior part of epiphysis involved with sequestrum formation.
- Group III: Almost whole epiphysis involved with sequestrum formation.
- Group IV: Whole epiphysis involved.
TREATMENT of PERTHES’ DISEASE:
A- Early Case (Irritable hip):
Rest in bed with skin traction and NSAID.
B- Established Case: Containment
the diseased femoral head is contained within the depth of acetabulum to equalize pressure on head and prevent deformity.
Containable non-deformed femoral head (arthrography).
Methods of Containment:
1- Conservative (age under 6 years):
Abduction brace for about one year until head is regenerated.
2- Operative (age greater than 6 years):
a- Femoral varus osteotomy: Deep seating of head within acetabulum.
b- Salter osteotomy: Acetabulum redirected downward forward & laterally to provide better coverage of the head.
Nursing care plan and intervention in PERTHES’ DISEASE
- Encourage the participation of family members to their child care to become more familiar to their management
- Encourage the child to participate in more activities as possible as he can
- Bed rest to allow more conservation of body energy
- encourage active range of motion exercises
- Provide home program for the child on discharge
- Emotional support to the child and his family