Access Keys:
Skip to content (Access Key - 0)

Posteromedial bowing of the tibia

Introduction

Posteromedial bowing of the tibia is a unilateral lower extremity deformity present at birth. It is characterized by varying degrees of apex medial and apex posterior deformity of the tibia and fibula. The exact etiology remains unknown

Clinical Presentation

  • This deformity, present at birth, is usually unilateral (left > right).
  • Boys and girls are affected equally.
  • By definition, apex posterior and apex medial bowing exists in the tibia and fibula, with the posterior bow > medial bow.
  • A dimple at the apex of the angulation may also be present.
  • A calcaneovalgus alignment of the ipsilateral foot is often noted at initial presentation.
  • Ankle range of motion may show increased dorsiflexion and reduced plantarflexion.
  • The patient may have a smaller calf circumference and smaller size foot (width and length) on the involved limb.

Natural History

  • Posteromedial bowing of the tibia is considered a benign condition because the bowing tends to correct spontaneously, although there is usually a residual leg length discrepancy.
  • The reduction in angulation of the bowing in both planes occurs most rapidly in the first year of life and then slows.
  • The posterior bow tends to correct faster than the medial bow.
  • The tibial shortening ranges from 15% to 40% at initial presentation and progresses to an average leg length discrepancy from 3 to 7 cm.
  • Children with increasing severity of bowing at presentation develop larger limb length discrepancies than those with less severe initial bowing.
  • Ankle valgus is common for the following reasons: Under age 2, eccentric ossification of the distal tibial epiphysis is common, and over age 2, wedging of the distal tibial epiphysis is common. The lateral malleolus may also be proximally located.

Differential Diagnosis

  • Anterolateral bowing – congenital pseudarthrosis of the tibia
  • Anteromedial bowing – fibular hemimelia

Treatment

  • At birth, no treatment is necessary for bowing, only observation over the first 2 years. Significant deformity should correct spontaneously (Figures 1-4).


Figure 1. Infant with posteromedial bowing of the tibia


Figures 2-3. AP (left) and lateral views of the same child's leg 7 years later. The deformity has spontaneously corrected itself.


Figure 4. Residual leg length discrepancy

  • Gentle stretching exercises may be utilized to correct dorsiflexion contracture of the calcaneovalgus foot deformity.
  • A shoe lift may be necessary to equalize leg lengths in the young child.
  • The role of surgical intervention is to correct residual bowing of the tibia, limb length inequality, and ankle valgus.
    • Bowing and limb length discrepancy can be corrected simultaneously with an external fixator.
    • Hemi-epiphysiodesis is effective at correcting ankle valgus in skeletally immature patient.

References

Hofmann A, Wenger DR. Posteromedial bowing of the tibia. J Bone Joint Surg 1981;63-A:384-388.

De Maio F, Corsi A, Roggini M, et al. Congenital unilateral posteromedial bowing of the tibia and fibula: Insights regarding pathogenesis from prenatal pathology. J Bone Joint Surg 2005;87-A:1601-1605.

Shah H, Doddabasappa S, Joseph B. Congenital posteromedial bowing of the tibia: a retrospective analysis of growth abnormalities in the leg. J Ped Orthop B 2009;18:120-128.

Peer Review

OrthopaedicsOne Peer Review Workflow is an innovative platform that allows the process of peer review to occur right within an OrthopaedicsOne article in an open, transparent and flexible manner. Learn more

Instructions for Authors

Read our Instructions for Authors to learn about contributing or editing articles on OrthopaedicsOne.

Content Partner

Learn about becoming an OrthopaedicsOne Content Partner.

Academic Resources

Resources on Posteromedial bowing of the tibia from Pubget.

Error rendering macro 'rss' : The RSS macro is retrieving an HTML page.
Orthopaedic Web Links

Internet resources validated by OrthopaedicWebLinks.com

Related Content

Resources on Posteromedial bowing of the tibia and related topics in OrthopaedicsOne spaces.

Page: Posteromedial bowing of the tibia (OrthopaedicsOne Articles)
Page: Congenital muscular dystrophy (OrthopaedicsOne Articles)
Page: Congenital myopathies (OrthopaedicsOne Articles)
Page: Congenital vertical talus (OrthopaedicsOne Articles)
Page: Coxa vara (OrthopaedicsOne Articles)
Page: Curly toes (OrthopaedicsOne Articles)
Page: Developmental milestones (OrthopaedicsOne Articles)
Page: Down's syndrome (OrthopaedicsOne Articles)
Page: Ehlers-Danlos syndrome (OrthopaedicsOne Articles)
Page: Enchondral ossification (OrthopaedicsOne Articles)
Showing first 10 of 252 results