Research
Recherche
From *the Oncidium Health
Group Inc., Burlington, 
Ont.; the Departments of
†Clinical Epidemiology and
Biostatistics, ‡Orthopaedics
and §Psychiatry, McMaster
University, Hamilton, Ont.;
¶the Department of Surgery,
Hospital for Sick Children,
University of Toronto,
Toronto, Ont.; and 
**the Chedoke Rehabilitation
Centre, Chedoke–McMaster
Hospital, Hamilton, Ont.
This article has been peer reviewed.
CMAJ
2002;166(4):437-41
Abstract
Background:
The effect of low-intensity ultrasonography on fracture healing is con-
troversial, and current management of fractures does not generally involve the
use of ultrasound therapy. We describe a systematic review and meta-analysis
of randomized controlled trials of low-intensity pulsed ultrasound therapy for
healing of fractures.
Methods:
We searched 5 electronic databases (MEDLINE, EMBASE, Cochrane
Database of Randomised Clinical Trials, HealthSTAR and CINAHL) for trials of
ultrasonography and fracture healing, in any language, published from 1966 to
December 2000. In addition, selected journals published from 1996 to Decem-
ber 2000 were searched by hand for relevant articles, and attempts were made
to contact content experts in the area of ultrasound therapy and fracture healing
as well as primary authors of reviewed trials. Trials selected for review met the
following criteria: random allocation of treatments; inclusion of skeletally ma-
ture patients of either sex with 1 or more fractures; blinding of both the patient
and the assessor(s) as to fracture healing; administration of low-intensity pulsed
ultrasound treatments to at least 1 of the treatment groups; and assessment of
time to fracture healing, as determined radiographically by bridging of 3 or 4
cortices. Two reviewers independently applied selection criteria to blinded arti-
cles, and selected articles were scored for methodologic quality. The internal
validity of each trial was assessed with the use of a 5-point scale that evaluates
the quality of trial method on the basis of description and appropriateness of
randomization and double-blinding, and assessment of study withdrawals and
likelihood of bias.
Results:
We identified 138 potentially eligible studies, of which 6 met our inclusion
criteria. Agreement beyond chance of quality assessments of the 6 trials was
good (intraclass correlation coefficient 0.77, 
p
= 0.03). One trial was a repeat
analysis of previously reported data, and 2 trials appeared to report on a shared
group of subjects. Three trials, representing 158 fractures, were of sufficient ho-
mogeneity for pooling. The pooled results showed that time to fracture healing
was significantly shorter in the groups receiving low-intensity ultrasound therapy
than in the control groups. The weighted average effect size was 6.41 (95%
confidence interval 1.01–11.81), which converts to a mean difference in healing
time of 64 days between the treatment and control groups.
Interpretation:
There is evidence from randomized trials that low-intensity pulsed
ultrasound treatment may significantly reduce the time to fracture healing for
fractures treated nonoperatively. There does not appear to be any additional
benefit to ultrasound treatment following intramedullary nailing with prior ream-
ing. Larger trials are needed to resolve this issue.
O
f the estimated 5.6 million fractures that occur annually in the United
States, 5% to 10% demonstrate delayed healing or nonunion.
1
In an effort
to reduce the substantial associated disability and socioeconomic costs,
2
a
variety of interventions have been proposed, including the use of low-intensity
pulsed ultrasonography.
1,3,4
The effect of low-intensity pulsed
ultrasound therapy on time to fracture
healing: a meta-analysis
Jason W. Busse,
*†
Mohit Bhandari,
†‡
Abhaya V. Kulkarni,
†¶
Eldon Tunks
§**
CMAJ • FEB. 19, 2002; 166 (4)
437
© 2002  Canadian Medical Association or its licensors