Femoral Anteversion – Normal, Abnormal, Causes, Symptoms, and Treatment

Last Updated on August 7, 2025

Femoral anteversion refers to the natural forward rotation of the femoral neck relative to the femoral shaft. It is a normal anatomical feature present in all individuals and typically falls within a defined physiological range.

However, in some people, the degree of rotation exceeds this range, a condition known as increased or excessive femoral anteversion. When this occurs, it may contribute to gait abnormalities, in-toeing, or other functional concerns, as discussed below.

Many articles refer to both as ‘femoral anteversion’ only but to avoid confusion, it is best to have clarity of the issue.

Femoral Anteversion and Use of the Term

The terms anteversion and retroversion describe the direction of rotation of an anatomical structure relative to a standard reference plane.

• Anteversion means the structure is rotated forward, toward the anterior.
• Retroversion means it is rotated backward, toward the posterior.

Thus, the version is compared to a reference position. For example, the normal uterus is typically slightly anteverted.

These terms are also commonly used in musculoskeletal anatomy, particularly for joints like the hip and shoulder. For example:

• The normal femoral neck exhibits anteversion. It projects forward about the femoral shaft.
• The humeral head typically shows retroversion relative to the distal humerus, oriented about 30° posteriorly.

In the context of the hip, femoral anteversion refers specifically to the forward angle of the femoral neck with respect to the femoral condyles. A decrease in this angle (or reversal) is known as femoral retroversion.

Definition:

Femoral anteversion is defined as the angle between an imaginary transverse line that runs medially to laterally through the knee joint and an imaginary transverse line passing through the center of the femoral head and neck. (see the diagram below)

The term medial femoral torsion is also used to describe femoral neck anteversion and is thought to result from medial or internal rotation of the limb bud in early intrauterine life.

It’s important to note that some degree of femoral anteversion is normal, and only deviations from the expected range are considered abnormal. Misuse of the term, referring to both normal and excessive angles simply as “femoral anteversion”, can confuse, especially in clinical discussions.

The femoral head has 12 to 15º of anteversion to the line connecting the posterior aspect of both femoral condyles. An increase in femoral anteversion beyond the typical value range can cause problems with alignment and gait, indicating an abnormality.

Thus, femoral anteversion is normal within a certain range. But an exaggerated level is an abnormality.

Special Note: Thus, technically speaking, there is normal anteversion of the femur and there is abnormal anteversion of the femur [when the normally present anteversion is exaggerated.]

However, in literature and in communication, both are addressed as femoral anteversion. In fact, I have come across various articles that relate the term femoral anteversion as an abnormality only.

Normally, the acetabulum is also slightly anteverted. Knowing the right version is important in designing arthroplasty implants and placement during surgery.

Note: When we say that the femoral neck is anteverted, we are taking it to the rest of the femur for comparison. The neck of the femur is anteriorly lifted or rotated when compared to that plane.

Normal Developmental Changes with Age

Femoral anteversion is not constant throughout life. It undergoes significant changes during skeletal growth and development, particularly in early childhood. [1]

• At birth, the femoral anteversion angle is relatively high, typically around 30° to 40°.
• With normal growth and muscular development, this angle gradually decreases.
• By adolescence (around age 16), the anteversion angle usually reaches the adult range of 10° to 15°.

This natural remodeling is influenced by mechanical forces, muscle activity, and weight-bearing during early childhood [2]. In most children, even if mild in-toeing is present due to increased anteversion, it improves spontaneously with age.

Developmental values by age:

Failure of this normal derotation process can result in persistent excessive anteversion, which may require clinical attention if symptomatic.

Abnormal or Excessive Femoral Anteversion

Excessive femoral anteversion refers to a condition where the femoral neck is rotated forward to a degree significantly greater than the typical adult range, often exceeding 30° in older children or adolescents. It is sometimes referred to as “increased femoral torsion” or “medial femoral torsion.”

An excessive femoral anteversion is a clinical problem. Some people refer to it simply as femoral anteversion.

It is often bilateral and more common in girls than boys. It becomes clinically apparent between the ages of 3 to 6, especially when intoeing persists beyond early childhood

While it is often a benign developmental variation, excessive anteversion may lead to functional limitations in select cases.

Definition:

It is defined as an anteversion angle that remains abnormally elevated beyond the age when physiological remodeling should have occurred. Clinically, it is considered significant when:

• Internal rotation of the hip exceeds 70°
• External rotation is limited (often less than 20°)
• Anteversion on imaging exceeds 30°

The condition is congenital and primarily related to developmental factors. The most common cause is intrauterine positioning, which affects how the femoral head and shaft are aligned during skeletal formation. In some cases, excessive anteversion may also be associated with:

• Neuromuscular disorders (e.g., cerebral palsy)
• Generalized ligamentous laxity
• Familial or genetic predisposition

Clinical Presentation and Diagnosis

Excessive femoral anteversion often presents in early childhood, typically around ages 3 to 6, when the normal remodeling of femoral torsion is expected to occur. The condition is most commonly identified by caregivers due to concerns about the child’s gait.

Common Clinical Features

• In-toeing gait (pigeon-toed appearance): The most classic and visible sign. Children may trip frequently or have awkward movement patterns.
• W-sitting posture: A distinctive sitting posture where the legs are bent inward at the hips and knees (also called reverse tailor sitting). It is commonly seen in children with increased internal hip rotation.
• Patellar medially facing during gait: Unlike tibial torsion or foot deformities, femoral anteversion causes the kneecaps to point inward as well.
  • Differentiates from other causes of in-toeing, like metatarsus adductus and tibial torsion.
• Occasional knee pain: Especially if there is concurrent tibial torsion or abnormal loading mechanics.
  • In extreme cases, sports activities and activities of daily life may be affected in older children.
  • There may be complaints of frequent tripping while walking.
• Altered Rotation of the hip: On examination, internal rotation is increased and may exceed 70°–80°. External rotation is decreased and may be less than 20°.
• Craig’s Test (Trochanteric Prominence Angle Test): It is a clinical test used to estimate femoral anteversion.

Imaging

Imaging is not commonly required. However, CT can be used for the exact measurement of anteversion in selected cases.

CT Scan (Gold Standard)

• This involves 3 axial images or scans—2 proximal and 1 distal.
  • One image defines the location of the center of the femoral head
  • Second image defines the base of the femoral neck
  • Third image defines the distal femoral condylar axis

The angle in the transverse plane between the intersection of the plane of the neck and the condylar plane defines the angle of anteversion.3 axial cuts are taken:

MRI and Ultrasound
Used in select pediatric or radiation-sensitive cases.

X-ray
Limited value for assessing anteversion, but may help rule out other hip pathologies.

Treatment

The management of excessive femoral anteversion depends on the age of the patient, severity of symptoms, and impact on function.

In most cases, the condition is benign and resolves naturally with growth. Therefore, only observation is needed. However, in a subset of cases, surgical intervention may be necessary.

Observation and Reassurance

• First-line approach for most children under 8–10 years of age.
• Parents should be reassured that:
  • The condition often improves spontaneously as the child grows.
  • Intoeing does not affect athletic performance or joint health in the majority of cases.
• Shoe inserts, braces, and physical therapy are generally ineffective and not recommended unless there is a coexisting issue.
• Activity Guidance:
  • Encourage normal activity and physical play.
  • Avoid prolonged W-sitting, which reinforces internal rotation posture.
  • In older children, sports that involve balance and coordination (e.g., swimming, cycling) may improve neuromuscular control.

Surgical Intervention: Femoral Derotational Osteotomy

Few children would require surgical correction.

Indications:

• Age >10 years
• Persistent functional impairment or cosmetic concern
• Internal rotation >85° with external rotation <10°
• Severe gait disturbance or frequent tripping

Procedure:

• Typically performed as an intertrochanteric or subtrochanteric derotational osteotomy [3]
• The femur is cut and rotated externally to normalize the anteversion angle.
• Fixation is achieved with plates, nails, or external devices.

Postoperative rehabilitation is important for optimal results. Generally favorable when well indicated.

Femoral Retroversion or Retroversion of Hip

Femoral retroversion refers to a femoral neck angle that is significantly less than the normal 10°–15° anteversion or even angled posteriorly in severe cases. Therefore, the retroversion means less anteverted than the normal range.

Just to reemphasize, the neck is less anteverted than normal and not angled backward necessarily compared to the femoral plane. Most of the patients have angles more than zero, few have zero angles.

However, very few patients may have a negative angle, which makes the femur actually angled backward. The whole spectrum falls under the term retroversion of the femur.

Clinical Features

• Out-toeing gait is the most prominent presentation.
• May be associated with limited internal rotation and excessive external rotation of the hip.
• Athletes or adults with retroversion may experience:
  • Hip impingement-like symptoms
  • Limited hip flexion or internal rotation during squats or running
  • Pain with prolonged sitting or physical activity

Radiological Diagnosis

• Best evaluated with CT imaging using axial slices at the head/neck and distal femur to determine the true version angle.
• X-rays are generally insufficient for angle estimation.

Clinical Relevance

• Retroversion can contribute to femoroacetabular impingement (FAI) and early hip osteoarthritis, especially if combined with other anatomical abnormalities.
• It may influence decisions in hip arthroplasty, osteotomies, or impingement surgeries.

Comparison Table: Femoral Anteversion vs Retroversion

References

1. Fabry G, Cheng LX, Molenaers G. Normal and abnormal torsional development in children. Clin Orthop Relat Res. 1994 May;(302):22-6. [PubMed]
2. Scorcelletti M, Reeves ND, Rittweger J, Ireland A. Femoral anteversion: significance and measurement. J Anat. 2020 Nov;237(5):811-826. [PubMed]
3. Naqvi G, Stohr K, Rehm A. Proximal femoral derotation osteotomy for idiopathic excessive femoral anteversion and intoeing gait. SICOT J. 2017;3:49.[PubMed]