Bone Stimulator Duration of Treatment for Nonunion Fractures
Direct Answer
For nonunion fractures, bone stimulators should be used for 20 minutes daily for a duration of 14 to 140 days (approximately 2 weeks to 5 months), or until radiographic healing is achieved, though the evidence supporting their efficacy is weak and most high-quality guidelines recommend against their routine use. 1
Evidence-Based Treatment Duration
Standard Treatment Protocol
Low-intensity pulsed ultrasound (LIPUS) devices are typically prescribed for 15-20 minutes each day for 14 to 140 days, though moderate to high-certainty evidence shows LIPUS has little or no impact on time to return to work, time to full weight bearing, pain, number of subsequent operations, or time to radiographic healing. 1
Electrical stimulation and electromagnetic bone stimulators follow similar duration protocols, typically used until clinical and radiographic union is achieved, with mean time to union ranging from 6.62 to 12.6 months depending on the fracture type and patient risk factors. 2, 3
Critical Guideline Recommendation
The BMJ clinical practice guideline (2017) strongly recommends AGAINST the use of LIPUS for bone healing, stating that all or nearly all informed patients would elect not to apply LIPUS, as it represents a costly device that does not represent wise use of health resources. 1
The guideline panel unanimously agreed that LIPUS is burdensome to use, with many patients reporting limited compliance in clinical trials. 1
Factors Affecting Treatment Duration
Smoking Impact
Tobacco smoking significantly increases time to healing with bone stimulators and is a significant factor in the need for revision nonunion surgery or salvage procedures after bone stimulator placement. 4
Smoking should be addressed as a modifiable risk factor before initiating bone stimulator therapy, as it directly impacts treatment efficacy. 4
Diabetes Considerations
Use of bone stimulators in patients with diabetes may be problematic, with studies showing union rates of only 65% in high-risk patients including those with diabetic Charcot neuroarthropathy. 5
Deep soft tissue infection or osteomyelitis in diabetic patients is a significant factor predicting prolonged time to healing, subsequent infection following bone stimulator placement, and need for revision or salvage surgery. 4, 5
Duration of Nonunion Prior to Treatment
The duration of nonunion before bone stimulator placement significantly affects outcomes, with patients started on treatment between 4 and 27 months from initial fracture (mean: 11.56 months) showing variable success rates. 3
Earlier intervention may improve outcomes, though the optimal timing remains unclear from available evidence. 3
Alternative Evidence on Electrical Stimulation
Moderate Quality Evidence for Pain Relief
Electrical stimulation produces a statistically significant improvement in pain (mean difference of -7.7 mm on 100-millimeter visual analogue scale) and reduces radiographic nonunion rates by 35% (number needed to treat = 7). 2
However, electrical stimulation shows no difference in functional outcomes between treatment and sham groups. 2
Combined Magnetic Field Stimulators
Combined magnetic field (CMF) bone growth stimulators show an 84% overall success rate with mean time to union of 6.62 months in patients with established fracture nonunion. 3
Treatment was initiated between 4 and 27 months from initial fracture, suggesting these devices may be considered after conventional treatment failure. 3
Clinical Algorithm for Decision-Making
Step 1: Initial Assessment
- Confirm nonunion diagnosis with radiographic evidence (typically after 6-9 months of failed healing)
- Assess modifiable risk factors: smoking status, diabetes control, infection presence
- Evaluate fracture stability and adequacy of fixation
Step 2: Risk Stratification
- High-risk patients (smokers, diabetics, infection history): Consider surgical intervention with stable fixation and autogenous bone grafting as primary treatment rather than bone stimulator alone 4
- Standard-risk patients: Bone stimulators may be considered as adjuvant therapy only after optimizing fixation and addressing risk factors
Step 3: Treatment Selection
- First-line: Optimize surgical fixation and bone grafting rather than relying on bone stimulators 1
- Adjuvant consideration: If bone stimulator is used despite weak evidence, prescribe for 20 minutes daily for 14-140 days or until radiographic union 1
- Monitor closely: Assess for complications including infection (15% deep infection rate in high-risk patients) 5
Critical Pitfalls to Avoid
Do not use bone stimulators as primary treatment for nonunion without addressing underlying mechanical instability, inadequate fixation, or infection. 1, 4
Do not prescribe bone stimulators in patients with active deep soft tissue infection or osteomyelitis without first treating the infection, as this significantly increases postoperative infection rates. 4
Do not expect high compliance rates with bone stimulator devices, as they are cumbersome to travel with and many patients report limited adherence in clinical trials. 1
Do not assume insurance coverage, as health insurance may not cover the cost of these devices, which represent significant expense without proven clinical benefit. 1
Special Population Considerations
Diabetic Patients with Charcot Neuroarthropathy
Bone stimulators in diabetic Charcot patients show only 65% union rates with 40% complication rates and 15% deep infection rates. 5
Two amputations (5%) were required in cases of intractable neuritis and deep infection in this population. 5