When broken bones are treated, new bone tissue begins to form and as it heals, the bone fragments connect and reform. While most bones heal without problems, when fractured or broken bones do not heal, they are referred to as non-union or malunion. Those with these non-healing breaks will experience constant pain at the site of the break long after the break should have healed. Non-union is when the bone does not heal properly, whereas malunion is when the bone heals but in the incorrect position.
Bone healing requires adequate stability, blood supply and good nutrition to heal properly. In some cases, when bone fractures and breaks are caused by high-energy trauma such as car accidents, malunion or non-union is more likely.
Management of malunion and non-union bone breaks may involve non-surgical or surgical methods or a combination of both.
Malunion occurs when a fractured bone heals in an abnormal position, but treatment is only sought if the malunion causes pain or functioning issues. A surgery called an osteotomy might be considered to realign, shorten or lengthen the bones that may have a malunion.
A non-union occurs when a fractured or broken bone fails to heal after extensive time. Non-surgical treatment options may include external electric stimulator or bracing. When necessary, surgery may be done to repair a non-union by restoring the bone and tissue surrounding the break or filling in the gaps with bone grafts to stabilise the bone. A bone graft is taken from another part of the body to provide the fracture site with a ‘scaffold' with fresh bone cells onto which it can grow.
A bone graft may not provide stability to the bone instantly and thus an internal or external fixation may be needed. Internal fixation is a metal plate which is attached to the outside of the bone with nails. An external fixation, however, is a rigid frame which is attached to the outside of the fracture site through wires or pins that are connected internally to the bone.