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Juho-AnttiAhola

Hip Pain in Children

The most common causes of non-traumatic hip or inguinal pain in growing children are transient synovitis of the hip, Perthes disease, slipped upper femoral epiphysis and overuse injuries of pelvic ossification centres.
Rare, but serious aetiologies of hip pain requiring emergency treatment are leukaemia, tumours and septic arthritis/osteomyelitis.

The most common cause of a sudden limp and refusal to walk in children between 3 and 10 years of age.
This is an aseptic inflammation of the joint capsule of the hip.
The child refuses to bear weight on the limb, complains of pain in the hip, thigh or knee, and holds the thigh in a flexed position and externally rotated with the knee bent. Hip rotation and extension are limited.
ESR may be slightly elevated.
An ultrasound examination of the hip will reveal possible effusion in the hip joint.
X-ray findings will be normal. X-rays are not necessarily indicated in early disease but should always be taken if symptoms persist for more than 2 weeks and when the patient is older than 10 years.

Another diagnosis is likely and further investigations are warranted if
- the symptoms have persisted for longer than two weeks
- the patient is under 2 or over 10 years of age
- the patient has fever or general symptoms
- CRP is higher than 20 mg/l or ESR higher than 35 mm/h.
Differential diagnoses include, in particular, Perthes disease, slipped upper femoral epiphysis, septic arthritis, osteomyelitis, juvenile idiopathic arthritis, osteoid osteoma and neoplasms.
Children with general symptoms and/or fever should be examined as emergency cases in specialized care.

The treatment of transient synovitis is symptomatic.
- Rest; the child should be allowed to keep the hip in the most comfortable position.
- Pain should be treated with NSAIDs.
The symptoms will subside in 2 weeks.
- If symptoms persist for a longer time, further examinations should be done in specialized care.

Circulatory disturbance of unknown aetiology involving the femoral head and causing bone fragility and hip pain.
Patients are typically boys between 5 and 9 years of age (the disease is 4 times more common in boys than in girls).

Symptoms usually develop gradually and fluctuate.
Limping gait
Pain in the groin, thigh or knee
ESR, CRP and blood leukocyte count are normal.
Diagnosis is based on X-raying: irregularity and consolidation of the subchondral bone structure is noted initially, followed by a decrease in the size of the femoral head in comparison with the unaffected side.

Perthes disease should be treated and followed up in specialized care, in a paediatric orthopaedic unit. Urgent (not emergency) referral is indicated.
The circulatory disturbance makes the femoral head more fragile. To prevent this, the load acting on the bone should be reduced.
Lighter exercise (such as swimming, cycling) should be used to maintain the range of hip motion and muscle strength.
The need for surgical treatment is assessed case by case.
The prognosis depends on the child's age at diagnosis and the extent of the circulatory disturbance.
The prognosis for functional recovery is usually good in children below 6 years of age.

The femoral head, or epiphysis, slides into a displaced position in relation to the femoral neck.
Onset may be acute or gradual.

The typical patient is an overweight child of 11 to 16 years of age with delayed puberty.
The disease is about twice as common in boys as in girls.
The patient has a limp and holds the limb in external rotation.
The clinical picture may be acute, with the pain starting suddenly, and the patient may not be able to place any weight on the limb.
The patient may describe the pain as being located in the groin, thigh or knee.
The diagnosis is based on X-raying. The shift can best be seen in the Lauenstein projection that should always be taken.

The situation is equivalent to femoral neck fracture: the patient should be referred as an emergency case to a paediatric orthopaedic unit.
Operative treatment is required, primarily closed reduction and screw fixation.
Patients run an about 10-20% risk of subsequent contralateral SUFE. Therefore, prophylactic fixation of the contralateral asymptomatic hip should be considered.
If the diagnosis is delayed, the femoral head may become ossified in a malposition, and open surgery will be needed to fix this. Such procedures involve a significant risk of circulatory disturbance in the femoral head and should be concentrated to specialized paediatric orthopaedic units (e.g. at university hospitals).

These conditions typically occur during the pubertal growth spurt, sometimes earlier.
They occur at the attachment sites of large muscle tendons, which are cartilaginous structures in children.
- Ischial tuberosity (hamstring muscles)
- Lower anterior pelvic tuberosity (rectus femoris muscle)
Analogous with Sever's disease in the heel and Osgood-Schlatter disease in the knee.
The symptom will be alleviated by pausing activities aggravating the pain.
The diagnosis is based on clinical findings (typical clinical picture, tenderness on palpation of typical site).
X-raying and laboratory tests can be done as necessary to exclude other causes of pain.
Symptoms will typically continue for a few weeks, but there is variation in both directions.
The condition will be finally alleviated with the ossification of the ossification centres.

Millis MB. SCFE: clinical aspects, diagnosis, and classification. J Child Orthop 2017;11(2):93-98 [PubMed]
Nouri A, Walmsley D, Pruszczynski B, et al. Transient synovitis of the hip: a comprehensive review. J Pediatr Orthop B 2014;23(1):32-6 [PubMed]
Cook PC. Transient synovitis, septic hip, and Legg-Calvé-Perthes disease: an approach to the correct diagnosis. Pediatr Clin North Am 2014;61(6):1109-18 [PubMed]