Nonunion/Malunion

“Nonunion” is a condition where fractured bone ends fail to heal. The period of time that elapses from the day you break your bone and when that break has been determined to be a nonunion is variable dependent on what bone is broken, certain characteristics of the break, and how it is treated. Many fractures treated with an operation will heal within 2-3 months from the time of surgery, and when not healed by that time might be referred to as a “delayed union”. In a delayed union, some bone forming reaction may have occurred but bone has not yet fully healed.  A delayed union may still heal without any further surgical intervention. If no healing reaction at all is present by 3 months a nonunion may have developed. Unfortunately, nonunions can occur even when you and your surgeon have done everything possible to get the fracture to heal. When a nonunion has developed, it may necessitate external bone stimulation, medications/supplementation, and/or additional surgical procedures including hardware revision, bone grafting, or a combination of the two. When a nonunion has developed, a consultation should be made with an orthopaedic fracture specialist who is proficient in the treatment of nonunions.
Humerus nonunion (left), healed after compression plating (center and right)

If you have been diagnosed with a nonunion, your physician may order laboratory tests in conjunction with other recommendations.

Some laboratory tests that your doctor may or may not order depending on your individual clinical situation include the following:

Vitamin D 25(OH)2

Vitamin D 1,25(OH)2

24 hour urine calcium

TSH

Free T3

Free T4

Testosterone/estrogen

FSH

LH

Alkaline phosphatase

 Parathyroid hormone

Growth hormone

Hgb A1C

ESR

CRP

WBC with differential

Aspiration/biopsy

Nicotine

Albumin

Pre-albumin

“Malunion” refers to a condition where a fracture heals in an abnormal position. This may mean that bone heals at an angle rather than straight, or with a rotational deformity. In a fracture involving a joint surface (such as the knee joint), it may also mean that the bone heals with a large step off along the surface of the joint rather than healing back to a smooth joint surface. Malunion can contribute to long term pain, limp, and abnormal wear of adjacent joints. Repair of a malunion may require “osteotomies” (cutting the bone) and re-aligning the involved bone.

Distal radius malunion (left) treated with osteotomies, plating, and grafting (right)

For further information on nonunions, see Dr. Riehl’s review publication on this topic:

Orthopaedic Tips: Nonunion

Riehl J, Fisher M. JBJS Journal of Orthopaedics for Physician Assistants: January-March 2018 – Volume 6 – Issue 1 – p e3

Abstract