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What is Paediatric Orthopaedics?
Paediatric Orthopaedics is the study and treatment of growing bones, joints and muscles. A Paediatric Orthopaedic Surgeon is dedicated to the care of musculoskeletal problems in children and adolescents and is a super-specialist in his/her field.
What are common Paediatric Orthopaedic conditions ?
Paediatric Orthopaedic conditions are relatively common. In most cases the observed abnormalities are simply variations of normal development and with growth these deformities undergo spontaneous correction. No treatment is therefore required for these cases. On the other hand, in a minority of cases the deformities are due to sinister conditions and treatment may be necessary.
- Developmental Dysplasia of the Hip (DDH)
- Intoe Gait
- Knock Knees & Bow Legs
- Flat Foot
- Calcaneovalgus Foot
- Irritable Hip
- Perthes' disease
- Growing Pains
- Club Foot
DEVELOPMENTAL HIP DYSPLASIA (DDH)
 This paediatric hip condition was previously known as congenital dislocation of the hip (CDH). In most cases the hip shows various degrees of dysplasia or subluxation (partial dislocation). In a small number of cases the hip may actually be normal at birth, but become abnormal later in life.
The incidence of this condition is about 2-4 cases per 1000 live births. Females are more frequently affected than males by 4:1. It may be bilateral in 25% of cases.
If this condition is detected early within the first few months of life, it could easily be treated with a short period of bracing with successful outcome in over 95% of cases.
Late presentation for example in a walking child is associated with a much worse prognosis. Treatment in the walking age group is generally more complex and prolonged, often requiring open surgical procedures. Early detection and treatment is therefore paramount to ensure a successful outcome and to avoid the need for major surgery.
Clinical Features of DDH are :
- Limitation of abduction in flexion (all age groups).
- Hip or thigh asymmetry (all age groups).
- Extra deep crease around the back of the thigh.
- Positive Barlow or Ortolani Tests (<2 months of age).
- Short leg or limping (walking age group).
- Treatment. The basic principles for treatment are:
- Reduce the dislocation or subluxation.
- Hold the reduction until hip stabilises.
- Careful follow-up until skeletal maturity.
In a child less than 6 months of age the reduction can easily be achieved by flexing and abducting the hips (frog position). The reduction is usually maintained using a brace such as a Pavlik harness for a period of 2-3 months.
In a child in the age group of 6-18 months this condition is associated with major soft tissue contractures. To achieve reduction a period of traction for 1 week is usually necessary. This is then followed by an attempt of closed reduction under general anaesthesia. The reduction would require confirmation using an arthrogram (injection of dye into the hip joint under X-ray control). In the cases that there is resistance to reduction, additional surgical procedures such as tenotomy (muscle release) or limited open reduction of the hip may be necessary. Following this procedure the reduction is maintained using a frog plaster for a period of at least 4 months.
In a walking age child (>18 months) major surgery is often required to reduce and stabilise the hip. this could be in the form of an open reduction of the hip +/- pelvic or femoral osteotomy. Postoperatively a period of casting in a hip spica is necessary for 10 weeks.
Prognosis for this condition is directly related to the age of the child at the time of presentation and the severity of the hip dysplasia.
In children less than 6 months of age 98% success rate is generally expected. This is reduced to 95% if the child is within the age group of 6-24 months and 85-90% if the child is over the age of 2 years at the time of treatment.
Careful follow-up until skeletal maturity (age 16 years) is needed to confirm satisfactory progress and to identify complications such as recurrent dysplasia or avascular necrosis (loss of blood supply to femoral head) at an early stage.
INTOE GAIT
 Intoe gait (pigeon toed) is a common childhood problem. It is estimated to occur in 10% of children between ages of 2-5 years. In most cases this is an entirely benign condition and is a feature of normal variation of growth pattern.
Lack of any symptoms such as pain, symmetrical deformities, absence of any stiffness in the affected joints and no associated systemic disorders or syndromes indicates a benign condition with excellent long-term outcome.
Most children with this deformity spontaneously stop intoeing before the age of 9 years. No treatment is therefore required in the majority of cases.
There are 3 main causes of intoe gait:
- Persistent femoral anteversion- usually requires no treatment
- Internal tibial torsion- this condition is unlikely to persist into adult life and rarely creates problems severe enough to require treatment or correction.
- Forefoot adductus- this condition has a tendency for spontaneous correction with age. Long-term prognosis is usually very good and treatment is not required in most cases.
For severe cases, especially when it is unilateral, application of serial corrective casts could be very effective. Surgical correction is rarely needed .
BOW LEGS & KNOCK KNEES
 Angular deformities of the lower limbs are common during childhood. In most cases this is an entirely benign condition and represents a variation in the normal growth pattern.
Presence of symmetrical deformities and absence of symptoms, joint stiffness, systemic disorders or syndromes indicates a benign condition with excellent long-term outcome. In contrast deformities which are asymmetrical and associated with pain, joint stiffness, systemic disorders or syndromes may indicate a serious underlying cause and require treatment.
Treatment is not required for physiological deformities. i.e. deformities within 2 standard deviation or deformities that are not associated with sinister features such as pain, asymmetry, stiffness, systemic disorders or syndromes.
Treatment for pathological deformities depends on the underlying disorder and the severity of the deformity.
Metabolic deformities such as rickets could simply be corrected with medical treatment i.e. calcium and vitamin D supplements.
For other deformities, depending on the age surgery in form of corrective osteotomy or partial growth plate arrest (hemiepiphysiodesis) may be needed.
FLAT FOOT
 Flat foot is a common finding in childhood. This is broadly divided into 2 groups i.e. flexible or rigid flat foot.
Flexible Flat Foot is the more common variety (95%). It is generally observed in the younger child and is frequently associated with generalised joint laxity. This condition is rarely symptomatic or limits the level of activity.
A classical finding in flexible flat foot is that the foot arch develops normally when the child stands on tip toes. whilst standing normally the flat foot deformity recurs.
In vast majority of cases flexible flat foot is an entirely benign condition and requires no treatment. Recent long-term studies have shown that old methods of treatment such as insoles or surgical shoes have no beneficial effect on the ultimate outcome.
Rigid Flat Foot on the other hand this is a sinister finding and often associated with serious conditions such as tarsal coalition or congenital vertical talus.
Unlike flexible flat foot, rigid flat foot is frequently a painful disorder. In this condition when the child stands on tip toes, the medial foot arch does not develop normally. On examination the foot is found to be stiff, lacking normal range of movement in the subtalar joint.
Congenital vertical talus (CVT) is a rare but serious foot deformity. It generally presents at birth and rarely responds to conservative treatment. 50% of cases are associated with underlying neuromuscular conditions or syndromes. Surgical intervention is frequently required as this is a painful condition as an adult. surgical correction is generally carried out at age 1 year.
CALCANEOVALGUS FOOT
This is the most common paediatric foot deformity. As the name implies, in this condition the hindfoot is in excessive calcaneus (dorsiflexed) and valgus position. In a walking child, on weight-bearing the foot has an excessively everted and pronated appearance.
This is an entirely benign condition in majority of cases. It is usually secondary to joint laxity and immature muscle pattern as seen in the newborn or a young child.
Other than gentle stretching exercises no other treatment is generally required and long-term prognosis is excellent.
CLUB FOOT (Congenital Talipes Equinovarus/CTEV)
 Club foot is the second most frequent paediatric foot condition. It affects 2 per 1000 live births and could be bilateral in 25% of cases. Males are more frequently affected than females by 2:1.
The deformities in club foot are complex and involves the whole foot, ankle and leg. In the hind foot the ankle joint is flexed (equinus deformity) and the heel is turned in (varus deformity). In the forefoot there is a high medial arch (cavus deformity) and the foot has a bean shaped and curled outer border (forefoot adductus deformity). The whole leg, foot including calf muscles are smaller on the affected side.
In 30% of cases this deformity is flexible and rapidly resolves after birth. In the remaining 70% the deformity is stiff and if left untreated it would lead to severe painful deformities in the long-term and the affected child could end up walking on the outer aspect of the foot.
Most cases of club foot are idiopathic (unknown cause) in nature and the child is otherwise entirely normal. In minority of cases (<5%) this deformity is secondary to other conditions such as neuromuscular disease or syndromes. There is also an increased risk of developmental dysplasia of the hip (DDH) in children with club foot and screening for this condition is therefore mandatory.
Treatment for flexible club foot is stretching exercises under the supervision of a physiotherapist. Rapid resolution of the deformity is generally expected within weeks and it is unlikely other methods of treatment would be necessary.
For rigid or inflexible deformities my preference is to use Ponseti's method of treatment. This is currently gathering increasing popularity and recent comparative studies have shown results equivalent or even superior to traditional methods of treatment such as surgical soft tissue releases.
Ponseti Treatment in my experience this is best suited for infants and young babies (< 6 months age).
Stretching and application of serial corrective casts
Treatment starts initially by stretching the deformity to its maximal position of correction and applying an above knee cast using plaster of Paris. This is repeated on a weekly basis for 6 weeks and a new cast is applied on each occasion.
In 20% of the cases complete correction of the deformities is observed within this 6 week period of stretching and casting. However, in 80% of cases the hind foot equinus deformity may persist. In these cases the complete correction of the deformity is achieved at week 7 by performing a small operation to release the tendo-Achilles (percutaneous tendo-Achilles release).
When complete correction of the deformities has been achieved an above knee cast is applied for another 6 weeks. At 12 weeks following start of treatment, all casting is discontinued.
The success rate of Ponseti treatment is about 85-90%. For failed cases or children with severe recurrent deformity, surgery may be required at a later date. Most cases with recurrent deformity after Ponseti treatment need a simple tendon transfer at the age 3-4 years (tibialis anterior tendon transfer).
Prognosis With appropriate treatment we expect most children (>95%) with clubfoot deformity to lead a normal life into adult hood.
In a small number of cases club foot deformity may not respond to stretching or Ponseti's treatment. These cases would require classical surgical soft tissue release at around age 1 year.
IRRITABLE HIP
This is the commonest cause of hip pain or limping in a young child. The peak age group is 3-8 years. Although this is a hip condition, in about 30% of cases the pain may initially be felt in the knee or the thigh.
The underlying pathology in this condition is formation of fluid under tension (effusion) within the hip joint. The exact cause of this effusion is unknown, but viral infections, minor trauma or allergy have been implicated.
Diagnosis is usually made on clinical grounds. The affected hip is generally irritable on movement but relatively comfortable when the hip is kept in the position of flexion and abduction. Signs of sepsis such as high temperature, rapid pulse, flushing, limb swelling or erythaema are notably absent.
Best method of investigation is ultrasound of the hip to confirmed the presence of the effusion and blood tests to rule out rise in inflammatory markers. Plain radiographs of the hips is also taken to exclude rare associations such as Perthes' disease. Radiographs may occasionally confirm presence of an effusion by showing a subtle medial joint space widening.
Treatment. Irritable hip is a benign and self-limiting condition. In most cases it spontaneously resolves within 48-72 hours. During the painful episode rest is advisable and this could be done at home. Other than anti-inflammatory drugs no other treatment is usually required.
If symptoms fail to resolve within the 48-72 hours or there is deterioration of general condition, urgent specialist review is necessary.
PERTHES' DISEASE
Perthes' disease is avascular necrosis of the femoral head of unknown aetiology. The interruption of the blood supply to the femoral head results in collapse, fragmentation and progressive deformity of the hip joint. It affects the age groups 4-10 years. Males are more frequently affected than females by 4:1 and it is bilateral in 25% of cases.
A child suffering from this condition usually presents with hip pain or a limp. However, in 30% of cases the pain may initially be referred to the thigh or the knee. This could on occasions result in missed or delayed diagnosis, especially if the hips are not radiographed routinely in a child with knee or thigh pain.
Perthes' disease is recognised to undergo a number of well defined radiological stages i.e. necrosis, fragmentation, healing and remodelling stages.
The Natural History of untreated Perthes' disease is eventual healing and revascularisation of the necrotic femoral head within 2-3 years. In 75% of the cases the healing process results in a round congruent hip joint with good to excellent outcome in the long-term. In these cases no treatment other than careful follow-up is necessary.
In contrast in 25% of untreated cases this condition results in severe deformity of the hip joint. In these cases operative intervention may be required to improve the outcome.
Progression of Perthes’ Disease
It is important to note that from onset of Perthes’ disease i.e. necrosis stage until the lesion heals (healing stage) it may take up to 2-3 years. Regardless of the prognosis, the affected child is expected to experience intermittent pain and limping during this period until healing stage is reached.
Treatment is not required for children with good prognosis.
In poor prognosis group operative intervention could improve the outcome. In general there are 2 class of operations available to treat Perthes's disease: i) Containment, ii) Corrective Osteotomy.
GROWING PAINS
This is a common condition, especially in the age group of 3-10 years. Classically symptoms are worse at nights. Usually the child wakes up in the middle of the night complaining of pain in both legs or knees. After a short period of massage and rubbing the painful area, symptoms resolve and the child goes back to sleep. In the day time symptoms are uncommon.
The exact cause of growing pains is unknown. It has been postulated that skeletal growth which mainly takes part at night, increases the limb length and this increases the stress on the soft tissues which tend to lag behind in growth.
Growing pains is a diagnosis of exclusion. Mode of presentation, age of the child and bilateral nature of the symptoms are strongly suggestive. However, thorough clinical examination and plain radiographs are needed to exclude rare but serious conditions such as tumours or infection which could mimic growing pains.
Treatment for this condition is symptomatic. Regular stretching exercises and a short course of mild painkillers at night could be helpful. In the long-term this condition spontaneously resolves.
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