2. US Therapy Versus NSAIDs Treatment
To date, there are a small number of studies that compare US therapy with NSAIDs, and they are focused only on the topical administration of NSAIDs.
Ibuprofen phonophoresis with US at 1 MHz frequency, 1 watt/cm
2 intensity, and ibuprofen cream containing 5% ibuprofen were found not significantly different in pain and function improvement rates compared to US therapy at the same parameters, administrated alone, in knee OA
[7], but one study communicated that the ibuprofen gel phonophoresis improved pain and Western Ontario and McMaster Universities (WOMAC) physical function score better than the ibuprofen cream phonophoresis
[8].
US therapy, at 1 MHz frequency and 1.5 watt/cm
2 intensity, had similar effectiveness as phonophoresis with topical gel containing 1.16% diclofenac diethylamonium on pain and physical activities improvement in knee OA patients, immediately after treatment and at 3-month follow-up period, except walking duration, when phonophoresis was more successful
[9].
In a previous study, diclofenac gel phonophoresis had similar efficacy on pain and functional status improvement in patients with knee OA for both continuous and pulsed mode (20% duty cycle) of US therapy (at 1 MHz frequency and 1.5 watt/cm
2 intensity), and both modalities of US therapy were more effective on pain and functional status than topical application of diclofenac gel
[10]. Instead, Diclofenac sodium phonophoresis that used US at 1 MHz frequency and 1 watt/cm
2 intensity was found to be more effective compared to isolated US therapy on pain, stiffness, physical function, and walking time improvement in patients with knee OA
[11].
US in continuous mode, 1 W/cm
2 power, and 1 MHz frequency had comparable efficacy to piroxicam gel phonophoresis (20 mg of piroxicam drug) on pain and total WOMAC score improving in knee OA, without significant differences
[12].
The association between US and TENS did not provide additional benefits, this mode of treatment having no significantly different results, compared to piroxicam gel, on pain and total WOMAC score improving in knee OA patients
[13].
Compared to US therapy (1 MHz frequency and 1.5 W/cm
2 intensity), ketoprofen phonophoresis (US at a frequency of 1 MHz, and intensity of 1.5 W/cm
2 + 100 mg of ketoprofen as 2.5% ketoprofen gel) had no significantly different efficacy on pain relief, WOMAC score, and 15 min walking test improvement
[14].
Unfortunately, all studies published to date compared the association of US and topical NSAIDs, namely phonophoresis, with US therapy and none of the studies compared the isolated administration of NSAIDs with US therapy.