Understanding Various Pediatric Lower Limb Abnormalities

Introduction

Pediatric lower limb abnormalities are a group of conditions in which a child may be born with lower limb deformations. Most of these conditions are congenital in nature. These abnormalities can be of various natures, such as shape, angulation, and length discrepancies. The deformities can develop as a child grows. These include bowlegs and knock knees.

Many cases of limb deformities may be transient in nature and may rectify as the child grows. malalignment may be rectified as the child grows in age. However, if the condition persists, it is advisable to obtain a medical opinion.

The treatment of these conditions depends on the severity of the condition. The treatment can be as simple as the usage of corrective footwear. If the deformity is of a serious nature, it may even require corrective surgeries. Bone lengthening surgery is one of the major surgical procedures that is undertaken.

What Are the Types of Pediatric Lower Limb Abnormalities?

The various types of pediatric lower limb abnormalities include-

• Bowleg deformity.

• Knock knees.

• Limb length discrepancy.

• Growth plate injury.

What Is Bowleg Deformity?

Bowleg deformity is a misalignment of the knees. This condition is also known as bandy legs. In this condition, the legs of the child may appear bowed or bent outwards. The knees may be bowed even when the ankles are placed together. It is normal for an infant to have a bowed leg. However, bowed legs should be a cause of concern if it is present even after the age of three years.

• Symptoms:

1. The most common finding of bowed legs is that the knees do not touch each other even when the ankles are placed together.

2. The child complains of pain in the hips or the knees.

3. There is limited motion of the hips.

4. The child faces an imbalance of the knees.

5. It can develop into arthritis as and when the child grows.

• Causes: The various causes of bowlegs can include-

1. Abnormal bone development.

2. Any damage occurs to the growth plate during pregnancy.

3. Other conditions, such as Paget's disease (a metabolic disease that affects bone rebuilding) and Blount’s disease (growth disorder of the growth plates)

4. External conditions such as fluoride and lead poisoning.

5. Vitamin D deficiency.

• Treatment - The treatment of this condition depends on the severity of the condition. Mild cases are treated with the help of the bracing technique. Serious cases may require surgery for the correction of the condition.

What Are Knock Knees?

Knock knees is a lower limb abnormality in which the knees are malaligned. There is an incorrect alignment of the knees. In this condition, the knees are bent inwards. They give the appearance of knocking against each other. The knees tend to touch each other even when the feet are placed away from each other. It can affect only one or both knees. Knock knees can put excessive pressure on the inner surface of the knees, leading to wear and tear.

• Causes - The following may be the causes of knock knees.

1. Abnormal bone development.

2. Any damage occurs to the growth plate during pregnancy.

3. Other conditions, such as Paget's disease (a metabolic disease that affects bone rebuilding) and Blount’s disease (growth disorder of the growth plates)

4. External conditions such as fluoride and lead poisoning.

5. Vitamin D deficiency.

6. Injury to the knees.

• Symptoms - The following are the symptoms of knock knees.

1. Knees positioned together.

2. Knee and hip pain.

3. Painful joints.

4. A change in walking pattern.

5. The child faces an imbalance of the knees.

6. It can develop into arthritis as and when the child grows.

• Treatment - Mild cases of knock knee can be treated with bracing or mild adjustment of the knees. If knock knee is caused due to any underlying infection or disease, it is important to address that first. Some cases of a knock knee may require surgery to rectify the condition.

What Are Growth Plate Deformities?

Growth plates are growing centers of any bony that are located at the end of it. If any fracture or injury occurs to it, it may cause abnormally formed bones or malaligned bones. There can also be fractures of the growth plates. When a fracture occurs at these sites, it can cause the bones to be weak and fragile. Injury can also cause the bone plate to close prematurely, leading to skeletal deformity. Fracture is the most common cause of growth plate deformity or injury.

• Symptoms: The symptoms of growth plate deformity include:

1. Abnormally formed or malaligned bones.

2. One leg is shorter than the other.

3. Injury or fracture to the growth plate when it occurs.

• Treatment: Any injury to the growth plate can be treated like a normal fracture. But this treatment requires proper splinting. The doctor may re-align the bone manually with the help of X-rays and other diagnostics. Sometimes, bone growth can be arrested, causing a deficiency. In such cases, external bars may be placed by means of surgery. These bars are placed depending on the amount of deficiency. If the deficiency of growth cannot be adjusted by the bar, a limb-lengthening procedure can be done.

What Is Limb Length Discrepancy?

Limb length discrepancy is when one leg is shorter than the other. The difference in the length can be present since birth or acquired during the child's growth phase. Some children can congenitally have one leg shorter than the other. This could be due to a genetic basis predisposition. A child can develop discrepancies during the growth phase due to an infection, such as cerebral palsy (overall muscle weakness), rheumatoid arthritis (an autoimmune condition affecting the joints), or osteomyelitis (inflammation due to an infection of the bone).

• Symptoms: The symptoms of limb length discrepancy can include-

1. One leg is shorter than the other.

2. Difficulty in walking.

3. Abnormal gait.

• Causes: The following may be the causes of limb length discrepancy.

1. Infections such as - osteomyelitis.

2. Rheumatoid arthritis.

3. Congenital issues.

• Treatment: The treatment for limb length discrepancy includes:

1. Limb lengthening process.

2. Usage of special shoes.

3. Usage of surgical blocks to manage the height.

Conclusion:

Lower limb abnormalities in children can be of various types. These can be congenitally present or can occur due to any infections or injury. Some types of abnormalities are acceptable until three years of age. However, if these persist, then one should obtain the opinion of a pediatric orthopedic surgeon.