Knock Knee - Types and Treatment

Introduction

Knock Knee is a commonly occurring condition that can be caused for various reasons. The bending of the bones leads to problems in performing daily activities like walking and running. The condition's underlying cause is detected, and the appropriate treatment is carried out. This article describes various types and treatments that treat knock knees.

What Is a Knock Knee?

Knock knee is also called genu valgum. It is a condition in which the ankles are spaced apart, and the knees are tilted inward. It can develop in any gender but most commonly occurs in females. The condition can be seen generally in growing children as a part of growth and development. In a few cases, the condition is well-demarcated, while in some, it is not. It can also detect the presence of underlying bone disorders.

What Are the Causes of Knock Knee?

Knock knees are developed during early childhood. As the child tends to walk, the knee tilts and helps the child balance.

Knock knees can be caused by the following reasons.

• Skeletal Dysplasias: It is a genetic condition leading to the abnormal formation of bones.

• Obesity: Obesity can also lead to knock knees. Gait abnormalities due to obesity, which resemble knock knees, can also occur.

• Injury: Injuries to certain areas in bones at the growth areas can lead to tilting the knee inward.

• Rickets: It is a metabolic bone disease due to a deficiency of vitamin D.

• Osteomyelitis: A condition occurring due to an infection in the bone.

• Arthritis: A condition in which the bones and joints are affected, causing pain and tenderness is called arthritis.

What Are the Types of Knock Knee?

Following are the types of knock knees:

Physiologic Variant: It is the most commonly occurring type of knock knee that gets corrected independently.

Pathologic Variant:

• Rickets (deficiency of vitamin D).

• Metaphyseal fracture (also called Cozens phenomenon is the fracture of the proximal portion of knee bones).

• Multiple epiphyseal dysplasias (the disorder of bone and cartilage that affects the ends of bones).

How Is Knock-Knee Associated With a Child’s Development?

• Knock Knee in Infants: Knock knees are usually not for infants. Many children have bow legs, where the legs are curved until they are 24 months old.

• Knock Knee in Toddlers: This condition becomes very obvious when the child is two to three years old. The knees tend to tilt inward until the age of four to five years.

• Knock Knees in Young Children: The legs of the child get aligned when they are about seven years old. Few will have knock-knees till they reach adolescence.

What Are the Symptoms of Knock Knee?

Following are the symptoms of knock knee:

• Inward angulation of the knees.

• Spacing of the ankles, touching the knees.

• Abnormal walking pattern.

• Feet rotated outward.

What Is the Diagnosis for Knock Knee?

The child's legs, knees, and ankles are examined to analyze the severity of the condition. Distance between two ankle bones is also measured. As the distance between the ankles increases, the severity can also be determined as high.

Diagnosis in children less than seven years of age is based on the following factors:

• Body mass index.

• Height of the child.

• Knee position when the child rotates or extends their legs.

• The symmetry of the legs.

• The pattern of walking.

In children aged above seven years, an X-ray can be advised based on the clinical condition and signs or symptoms.

X-rays are not usually recommended in children unless the child is facing problems in walking, playing, or running to avoid extra radiation.

What Are the Treatment Options for Knock Knee?

Children with knock knees showing no major difficulties need no treatment intervention. The child usually shows knock knees between two to five years of age. The commonly advocated treatment is close observation and follow-up. Almost all children pass this condition by the time they turn seven years of age.

Nonsurgical Options:

In cases where major symptoms and knock knees persist even after seven years, any underlying condition related to bones is checked for and eliminated. If there is a presence of an underlying condition, treatment is dependent on curing the cause. The case of rickets can explain this. Rickets is a condition occurring due to the deficiency of vitamin D. Hence, to treat this condition, calcium and vitamin D supplements are administered.

Surgical Options:

Surgery is recommended in rare cases when the condition does not relieve itself.

• Guided Growth Surgery: It is a surgery that treats knock knees by decreasing the rate of growth on the affected site or bent site of the bone so that the growth on either side can be brought to the same rate. As the outer side of the bone grows, the legs become straighter. This surgery is carried out when the child is attaining puberty at the age of 12 for boys and 11 for girls.

Osteotomy Surgery:

Major deformities that do not get corrected as the child grows are corrected by osteotomy surgery. The angle of the bones is changed to straighten the legs. This procedure is done by cutting the bone and realigning it above or below the knee portion.

After osteotomy surgery, the child is admitted to the hospital for a few days. Precautions to be followed at home after discharge are strictly advised to the patient.

The following are the precautions:

• Limit activities that require weight bearing.

• Walker or crutches are used for support while walking for nearly ten weeks.

• Physiotherapy to strengthen muscle strength is advised.

• The child is restricted to activities until six months, and then after, the child can return to his daily activities.

What Is the Prognosis of Knock Knees?

No treatment is required for knock knees when it develops before seven years of age, and a long-term positive outlook is obtained. Surgical and nonsurgical procedures both show the safest outcomes. Children with severe bone deformities find it difficult to improve and take a longer time to recover.

Conclusion

Knock knees are a generally occurring condition in one's growth and development during early childhood. Care must be taken to observe the changes that can occur keenly. The symptoms should be found to be reduced or should be corrected on their own until seven years of age. Once the condition does not rectify on its own, treatment intervention should be done either surgically or non surgically. Knock knees have a good prognosis when treated. The child must be taken to the physician on the development of any major symptoms to treat the condition as well as the cause behind the condition.