Basics
Description
- Intoeing, as a presumptive diagnosis, results in numerous orthopedic consultations.
- Causes of intoeing are most frequently one or more of the following: metatarsus adductus, internal tibial torsion, and femoral anteversion.
- Definitions:
- Version: normal variation in axial alignment
- Torsion: any variation beyond two standard deviations of normal
- Clear explanation of the difference between physiologic variations and pathologic anatomy will allow the treating physician to effectively manage expectations.
Epidemiology
Very common; one the most common reasons for a "well child"� to visit an orthopedist �
Risk Factors
Genetics
No strong evidence of familial links �
Pathophysiology
- Most are self-limiting issues but when paired together, can cause significant issues.
- Excessive femoral anteversion and external tibial torsion can result in the so-called "miserable malalignment,"� known to cause significant patellofemoral issues.
Etiology
- In utero, fetuses are subjected to forces that mold feet and tibiae into adductus and internal torsion, respectively.
- Most children are born with a relatively increased femoral anteversion (approximately 45 degrees).
- Tends to resolve and "unwind"� as the child develops
- Usually resolves by age 8-10 years to the normal adult anteversion of 10-20 degrees
Associated Conditions
May be more common in first-born children (especially metatarsus adductus) as part of the "packaging disorders"� such as developmental dysplasia of the hip and torticollis �
Diagnosis
History
- Varies based on age of presentation
- The most common reasons for malalignment visits in the preambulatory infant are either intoeing due to metatarsus adductus, or due to an external hip rotation contracture that all children have, which results in an obligatory and physiologic outtoeing.
- The ambulatory toddler will commonly come in with either intoeing or "bowleggedness"� as a complaint.
- The bowleggedness is almost always physiologic or related to the illusion of genu varum due to the child externally rotating their hips to prevent tripping over their internally rotated feet.
- Intoeing in an older child is most often due to femoral anteversion, which is slightly slow to "unwind."�
- The most common complaints are as follows:
- Frequent tripping
- Motor delay that is slower than peers or other relatives
- Family member observation (e.g., an older relative who insists "something is wrong"�)
- There may be also be an adult family member with similar issues who did not "grow out of it,"� prompting an early evaluation.
Alert
Functional limitations (such as tripping and falling frequently) may suggest other diagnoses, such as mild cerebral palsy, especially if abnormal birth history, abnormal developmental milestones, and physical findings consistent with cerebral palsy. �
Physical Exam
- Goal to rule out significant pathologies that could cause the relatively benign complaints
- For example, any male child with a history of clumsiness must get a Gower test and deep tendon reflexes to rule out muscular dystrophy.
- If possible, observe the child exploring the room before starting the physical exam. The examiner may gain more information here than at any other point in your exam.
- Watch the child walk and run in the hallway.
- Ask the child to toe walk, heel walk, and use tandem gait (walk in a straight line touching the heel of one foot to the toes of the other foot) to further explore levels of coordination and function.
- Look at the foot progression angle (angle formed between axis of foot and axis of forward progression of gait); normally 6-10 degrees of external rotation. An abnormal angle should be explainable by looking at rotation of other parts of leg during gait (hip rotation, thigh-foot angle, and/or foot abnormalities). If something does not add up, ask the child to walk again.
- Gait can be too complex to observe all at once. If necessary, focus on one level (hips, knees, feet) at a time and have the child walk back and forth numerous times.
- A "quick hint"� is to watch the patella when evaluating the knees; they should always be roughly collinear with the feet.
- All children should have a thorough hip exam to rule out hip dysplasia as a cause.
- All children have their hip abduction checked; any asymmetry is further evaluated with pelvis x-rays.
- Children younger than 2 years: Get a Barlow/Ortolani to check for hip instability.
- Barlow: Adduct hip (thigh toward midline) applying light pressure on knee and direct force posteriorly. Positive sign if femoral head dislocates.
- Orltoani: Flex hip to 90 degrees, use index fingers to place anterior pressure on greater trochanters, and abduct the legs using thumbs. Positive sign is "clunk"� as femoral head relocates in acetabulum.
- The usefulness of a prone hip rotation exam far outweighs that of the supine exam.
- When examining for tibial torsion, there are a few different methods to evaluate the angle.
- Thigh-foot axis
- With the patient prone and the knee flexed 90 degrees, measure the difference between the axis of the foot and the axis of the femur.
- The angle of the foot should be approximately 15 degrees externally rotated.
- Transmalleolar axis
- With the patella facing the ceiling, the axis between the floor and a line drawn through the malleoli is measured.
- Twenty degrees external is normal.
- 2nd toe test
- With the patient prone, the second toe is rotated until it is perpendicular to the floor.
- The femur is then held in place and the knee is flexed 90 degrees.
- The angle of the tibia to the vertical should be roughly 20 degrees.
- Metatarsus adductus is assessed by looking at the sole of the foot and drawing a bisecting line from the center of the heel distal. The line should travel through the 2nd and 3rd webspace. The further lateral the bisector line exits the foot, the more severe the adductus.
- Spontaneous correction of the adducted forefoot is a positive sign and is assessed by gently stroking the lateral border of the foot.
- Assess for limb length differences.
- Asses deep tendon reflexes.
Diagnostic Tests & Interpretation
Lab
Never useful for simple torsion �
Imaging
- Almost never ordered for run-of-the-mill torsional exams
- Order AP and frog pelvis films if there is a high suspicion of hip dysplasia.
- A standing (or supine) AP limb alignment x-ray can be a useful tool to examine for frontal plane abnormalities; taken from pelvis to ankles
- Should be standardized at each institution with patellae facing the beam
- In the event of significant torsion, advanced imaging (e.g., CT or MRI) can be ordered to discover the true anatomic axes. This is almost always obtained exclusively as a preoperative tool.
Differential Diagnosis
- Almost always the diagnosis is that of physiologic alignment.
- The examiner must rule out cerebral palsy, muscular dystrophy, hip dysplasia, etc.
Treatment
- The younger child (younger than 8 years) should spontaneously resolve minor internal torsion of the tibia and femur.
- Corrective shoes, Denis-Brown bars, twister cables, stretching, and formal physical therapy no more effective than observation. In addition, there has been some correlation of poor self-esteem in those patients prescribed with braces.
- Observation is the rule.
- There are no restrictions to activity, in fact the children should be encouraged to be active.
- Recalcitrant torsion in the older patient may be an indication for osteotomy to derotate the limbs, only very rarely recommended.
- Managing family expectations is crucial.
- It may be helpful to have a handout to give to families, to both explain the issues and to show the frequency with which the diagnosis shows up in the office.
- Get comfortable with a standard explanation of the normal physiology; use terms that are easy to understand.
- Families may be reassured by data suggesting positive correlation with intoeing and elite-level sprinting.
Ongoing Care
Prognosis
- Most patients are discharged with follow-up "as needed"� with instructions to return if the problem hasn't improved over a period of 2 years or if the problem acutely worsens.
- Patience is strongly encouraged, as the "unwinding"� of the limbs takes years to occur.
- The overall prognosis is excellent.
- This is a very common reason for an orthopedic visit and a very rare reason to go the operating room.
Complications
Many patients will come in already having seen practitioners (podiatry, physical therapy, chiropractic, orthotists) who will associate torsion with degenerative arthritis and as a cause of more proximal issues (hips, spine). The evidence for this is anecdotal at best. �
Additional Reading
- Craig �CL, Goldberg �MJ. Foot and leg problems. Pediatr Rev. 1993;14(10):395-400. �[View Abstract]
- Fuchs �R, Staheli �LT. Sprinting and intoeing. J Pediatr Orthop. 1996:16(4):489-491. �[View Abstract]
- Schoenecker �PL, Rich �MM. The lower extremity. In: Morrissy �RT, Weinstein �SL, eds. Lovell and Winter's Pediatric Orthopaedics. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005:1157-1212.
- Staheli �LT. Lower positional deformity in infants and children: a review. J Pediatr Orthop. 1990;10(4):559-563. �[View Abstract]
Codes
ICD09
- 754.43 Congenital bowing of tibia and fibula
ICD10
- Q68.4 Congenital bowing of tibia and fibula
SNOMED
- 108761000119101 Congenital internal tibial torsion (finding)
- 275864001 On examination - intoeing (finding)
FAQ
- Q: Are special shoes or braces ever indicated for tibial torsion?
- A: Almost never. There is no convincing evidence that any of these treatments truly alter the natural history of the condition. The situation will improve without treatment in most children.
- Q: Why do patients with torsional pathology occasionally have knee pain?
- A: Children may have increased femoral anteversion with associated external tibial torsion (i.e., an external rotation of the tibia that matches and, in effect, balances the internal rotation of the femur). This can be diagnosed by observing the rotational profile and by noting an increased Q-angle of the knee. This situation is sometimes a "setup"� for patellofemoral pain.