What is the evidence for the use of ultrasound in the treatment of osteoarthritis of the knee?
AMSTAR Rating
Summary
Patient Population:
All trials included patients with knee OA only. For the majority, the severity required simple, non-surgical intervention only.
Intervention:
Continuous or pulsed therapeutic ultrasound. All trials provided concurrent standard treatment in addition to the ultrasound intervention in both the ultrasound and control conditions. The authors note that details of treatment were not well described. Median number of treatment sessions per week was 3 (range = 2-5). Median length of treatment period = 8 weeks (range = 2-8).
Comparison:
Control conditions: sham treatment (3 trials). There were 5 RCTs identified for inclusion in the present review. Two trials examined the use of pulsed US, 2 examined continuous US and the remaining study evaluated the use of both as the active treatment components of the trials. The quality of trials was relatively poor. No trials reported adequate randomization sequence generation or concealment of allocation. No trials performed an adequate ITT analysis or included a sample size large enough to provide sufficient power to detect a small to moderate SMD. Overall, the quality of the evidence was classified as low given the risk of bias in the small trials of poor quality. There was no significant publication bias demonstrated.
Outcome:
- Pain: ultrasound vs. sham/no treatment (4 studies) – significant difference in favour of ultrasound at 2-6 weeks (SMD=-0.49; 95% CI -0.76 to -0.23; NNT = 6; GRADE = low).
- Function: ultrasound vs. sham/no treatment (4 studies) – non-significant difference in favour of ultrasound at 2-8 weeks (SMD=-0.64; 95% CI -1.42 to 0.14; GRADE = low).
- Adverse Events: Data was abstracted from only one study. No adverse events were reported in the therapeutic ultrasound condition.
