Knock knees, medically known as genu valgum, describe a condition where the knees angle inward, causing them to touch or nearly touch, even when the ankles remain separated. While often a normal part of development in children, knock knees can sometimes persist or develop due to other underlying factors.
Understanding Knock Knees
Knock knees can manifest in two primary forms: physiological and pathological genu valgum. Physiological genu valgum is a common developmental stage observed in young children, typically appearing around two to three years of age and often becoming most prominent between ages three and four. In most cases, the condition naturally corrects itself, with the legs usually straightening by the age of seven or eight years.
Pathological genu valgum, in contrast, involves persistent or severe inward angulation of the knees. This form can stem from various causes. Conditions like rickets, a bone disease caused by a lack of vitamin D and calcium, are a known cause. Obesity can also contribute to or worsen knock knees by placing increased stress on the knee joints. Additionally, genetic conditions such as skeletal dysplasias, or injuries to the growth plates around the knee, can lead to pathological cases, sometimes affecting only one leg.
Non-Surgical Approaches for Correction
For many individuals, particularly children with physiological genu valgum, non-surgical approaches are the initial course of action. Physical therapy plays a role in managing symptoms and improving musculoskeletal balance. Exercises often focus on strengthening key muscle groups that contribute to lower limb alignment and stability.
Stretches aimed at improving flexibility in tight muscles can also be beneficial in promoting better joint mechanics. Consistency in performing these exercises and stretches is important for achieving potential improvements. While braces and specialized footwear were historically used, they are generally not considered effective for correcting the underlying alignment in most cases of physiological knock knees.
Medical and Surgical Interventions
When non-surgical methods prove insufficient or for severe cases of knock knees, medical and surgical interventions may be considered. If a vitamin D deficiency, such as rickets, is identified as the cause, medical treatment often involves supplementation with vitamin D and calcium to address the underlying bone mineralization issue. This can help improve the condition, especially in children where the bones are still developing.
Surgical options are typically reserved for more pronounced deformities, cases that cause pain or functional limitations, or those that persist beyond the age when spontaneous correction is expected. In growing children, guided growth surgery, also known as hemiepiphysiodesis, is a common procedure. This involves placing a small plate or screws on one side of the growth plate near the knee, which temporarily slows growth on that side, allowing the other side to catch up and gradually straighten the leg over time. For adults or severe pediatric cases where growth plates have closed, an osteotomy may be performed. This procedure involves surgically cutting and reshaping the bone to realign the limb and improve joint mechanics.
When to Seek Professional Guidance
It is advisable to seek professional medical guidance when knock knees exhibit certain characteristics that suggest a need for intervention. Parents should consult a doctor if their child’s knock knees persist beyond five to seven years of age, appear before age two, or worsen over time. Noticeable asymmetry where only one leg is affected, or if the condition is accompanied by pain, a limp, or difficulty walking or running, warrants medical evaluation.
If knock knees develop in adolescence or adulthood, or if there is a significant gap between the ankles when standing with knees together (typically greater than 8 centimeters or 3 inches), a medical consultation is recommended. Early diagnosis and appropriate management can contribute to better long-term outcomes and help prevent potential complications such as knee pain, joint instability, or the premature development of arthritis.