Can a nonunion fracture eventually achieve bone union after one year?

From the Guidelines

A nonunion can eventually heal and grow bone even after a year, though the likelihood decreases with time, and treatment options such as surgical intervention or non-surgical methods like low intensity pulsed ultrasound (LIPUS) can still lead to successful bone union. Nonunions are fractures that have failed to heal within the expected timeframe, typically 6-9 months, and it is estimated that 5-10% of fractures experience delayed healing or non-union 1. Treatment options for long-standing nonunions include surgical intervention with internal fixation (plates, screws, rods) combined with bone grafting to provide stability and biological stimulation. Autologous bone graft (taken from the patient's iliac crest) remains the gold standard, though synthetic bone substitutes or bone morphogenetic proteins (BMPs) may be used. Non-surgical options include external bone stimulators (electrical, ultrasound) which may help in select cases, as supported by a clinical practice guideline on low intensity pulsed ultrasound (LIPUS) for bone healing published in the BMJ in 2017 1.

The healing potential depends on several factors including:

• the location of the nonunion
• blood supply to the area
• patient factors (smoking status, diabetes, nutritional status)
• and whether the nonunion is atrophic (poor biological activity) or hypertrophic (good biological potential but inadequate stability). Optimizing vitamin D levels, calcium intake, protein nutrition, and avoiding tobacco use can support bone healing, as these factors can influence the bone's ability to heal and grow. While spontaneous healing after one year is uncommon, appropriate intervention can still lead to successful bone union even in long-standing cases, highlighting the importance of timely and effective treatment.

From the Research

Nonunion and Bone Growth

• A nonunion is a fracture that will not consolidate without any further intervention, and it is estimated that approximately 10% of fractures result in nonunion 2.
• The current definition of nonunion states that it is a fracture that will not consolidate without any further intervention, independent of the treatment time 2.
• Nonunion can be treated with various methods, including surgical and non-surgical options, such as bone growth stimulators 3, 4.

Treatment Options for Nonunion

• Surgical treatment options for nonunion include reosteosynthesis, vascularization, and the application of osteoconductive carriers and osteoinductive substances 2.
• Non-surgical treatment options for nonunion include the use of pulsed ultrasound, electrical or magnetic bone stimulators, and combined magnetic field bone growth stimulation 3, 4.
• The use of combined magnetic field bone growth stimulators has been shown to be a viable treatment option for established fracture nonunion, with an overall success rate of 84% and a mean time to union of 6.62 months 3.

Potential for Bone Growth after a Year

• While there is no direct evidence to suggest that a nonunion can eventually grow bone after a year without treatment, studies have shown that treatment with bone growth stimulators can promote bone healing and union in patients with nonunion 3, 4.
• The success of treatment for nonunion depends on various factors, including the type of fracture, the presence of infection or large defect gaps, and the individual patient's risk profile 2.