Malunion - What Is a Malunion

A malunion occurs when the fractured ends of a bone heal in an abnormal position. It can result in bending, rotation or shortening of the bone with loss of function.

Immobilization of the fractured bone is a critical step in proper bone healing. Malunions may be caused by inadequate immobilization of the fracture areas, improper positioning during immobilization or bone loss during the injury. 

A malunion may be associated with pain, tenderness, swelling, deformity or difficulty bearing weight. If a malunion involves a joint, it can result in an irregularity of the smooth cartilage which interferes with movement producing pain, swelling and degeneration (arthritis).

When you present with symptoms of a malunion, your doctor will review your history and perform a physical examination. Imaging studies such as X-rays, CT scan, MRI scan or bone scan may be obtained for a more detailed view.

Your doctor may suggest not treating a malunion that does not affect function or have any other adverse effects. If treatment is necessary, it usually involves surgery to cut the bone (osteotomy), reunite the fragments in the correct position and secure it with pins attached to an external frame, wires, rods, plates and/or screws.

  • The American Board of  Orthopaedic Surgery
  • Allegheny General Hospital
  • University of Pittsburgh  Medical Center
  • University of Cincinnati College of Medicine
  • American Society for Surgery of the Hand
  • American Association for Hand Surgery: AAHS
  • Alpha Omega Alpha