What Is Femoral Retroversion And What Causes It?

Femoral retroversion is a condition where the thigh bone (femur) is rotated backward relative to the hip socket. This means the knee and foot point outward more than usual, though in practice the gait often appears toed-in because the lower leg compensates. The condition is typically present from birth and often improves on its own as a child grows. The exact cause is not fully understood, but genetics and the position of the fetus in the womb are thought to play a role.

What Is Femoral Retroversion And What Causes It

Femoral retroversion describes the angle of the femoral neck relative to the shaft of the femur. In a normally developed adult, the femoral neck angles forward about 12 to 15 degrees. This is called anteversion. In retroversion, that angle is reduced or reversed — the neck points backward instead of forward. This alters how the leg rotates at the hip.

The cause is developmental. During fetal growth, the femur normally rotates from an initial retroverted position to a more anteverted position. If that rotation does not happen fully, the femur remains retroverted. Genetic factors influence this process. Some cases are linked to other conditions such as developmental dysplasia of the hip or neuromuscular disorders like cerebral palsy. But most cases of isolated femoral retroversion have no identified cause — they are idiopathic.

How Does Femoral Retroversion Affect Movement

The backward twist of the femoral neck changes the orientation of the hip joint. The leg tends to rotate outward when the hip is extended, but people often compensate by turning the lower leg inward. This can make the feet point straight or even inward during walking, creating an intoeing gait.

In children, this gait is usually painless and often improves without treatment. In adults who still have significant retroversion, common complaints include hip pain, groin pain, and difficulty with activities that require hip rotation, such as sitting cross-legged or squatting. Some studies suggest that persistent femoral retroversion may increase the risk of hip osteoarthritis over time, but the evidence for this is not strong.

How Is Femoral Retroversion Diagnosed

Doctors typically start with a physical exam. The most common test is the Craig test, also called the trochanteric prominence angle test. The patient lies face down with the knee bent 90 degrees. The examiner rotates the hip until the greater trochanter is most prominent on the side. The angle of the lower leg relative to vertical gives an estimate of femoral version.

If the exam suggests retroversion, imaging can confirm it. CT scan is the most accurate method. MRI can also measure the version angle without radiation. X-rays are less precise but can give a rough measurement. In children, doctors often rely on physical exam alone and do not image unless symptoms are severe or the condition does not improve with age.

Treatment Options for Femoral Retroversion

For most children, treatment is not needed. The version angle often corrects naturally as the skeleton matures. Regular observation by a pediatrician or orthopedist is usually enough. Physical therapy cannot change the bone angle, but it can address muscle imbalances or gait issues that may develop.

Surgery is considered only when retroversion is severe and causes persistent pain, significant gait problems, or functional limitations that do not improve. The procedure is called a femoral derotational osteotomy. The surgeon cuts the femur, rotates it to a more normal angle, and fixes it with plates or screws. This is a major surgery with a recovery period of several months. It is not done lightly and only after careful discussion of risks and benefits.

For adults with mild retroversion and no symptoms, no treatment is needed. For adults with symptoms, the first approach is usually conservative: activity modification, stretching, and strengthening exercises. Surgery is reserved for cases where nonoperative measures fail and symptoms severely affect quality of life.

Can Femoral Retroversion Be Prevented

There is no known way to prevent femoral retroversion because it develops before birth. The condition is not caused by anything a parent does or does not do during pregnancy. Carrying positions, swaddling, or baby gear do not cause or correct femoral retroversion. If you are concerned about your child’s gait, talk to a pediatrician. Early diagnosis is helpful but prevention is not possible with current knowledge.