Pulsed Short Wave in Females With Knee Osteoarthritis (PSW)

Irmandade da Santa Casa de Misericordia de Sao Paulo

Status: Completed

Conditions: Chronic Diseases; Knee Osteoarthritis

Treatments: Device: Pulsed short wave

Study type: Interventional

Funder types: Other

Identifiers

NCT01331174

403/06

Details and patient eligibility

About

Study design: Randomized clinical trial. Objective: To evaluate the effect of PSW treatment in different doses and to compare to the control and placebo group.

Background: Several forms of conservative treatment have been the focus of many recent studies in knee osteoarthritis (OA). Among these techniques, the application of pulsed short wave has been widely used, but the optimal dose and application time still have not been well established.

Full description

Methods: One hundred and twenty-one females (average ± sd age, 60 ± 9 years), with a diagnosis of knee OA were distributed randomly into 4 groups: 35 patients who did not receive any treatment (control), 23 patients in the placebo group, 32 patients in the low dose PSW group (14.5W, 19 minutes and 17KJ), and 31 patients in the high dose PSW group (14.5W, 38 minutes and 33KJ). An 11-point numerical pain rating scale (NPRS) and "Knee Osteoarthritis Outcome Score" (KOOS) were used to assess pain and function in 3 stages: initial evaluation (pre-treatment), immediately after post-treatment, and a 12-month follow up.

Results: The 4 groups were homogeneous prior to treatment with respect to demographics, pain, and functional scales data. We demonstrated the short-term effectiveness of the PSW at low or high doses in patients with knee OA. Both treatment groups showed significant improvement in pain and function when compared to the control and placebo groups (P<0.05). There were no differences between PSW doses, despite the fact that a low dose of PSW seems to be more effective in the long term.

Conclusion: The PSW is an effective method for pain relief, functionality, and quality of life improvement in females with knee osteoarthritis in the short-term. On the basis of our results, we recommend PSW application in the female population with knee OA. However, conclusions regarding the 12-month follow up should be analyzed carefully due to the high dropout rate.

Enrollment: 121 patients

Sex: Female

Ages: 40+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• The female subjects were included if they were over 40 with knee primary grade II or III OA, based on Gupta et al radiographic criteria2, and joint or anterior knee pain for at least 3 months.

Exclusion criteria

• We excluded patients with a history of surgery or any invasive procedure of the affected knee, physical therapy for knee injuries or any medication that had changed in the last 3 months, other diseases changing function, and patients who presented any contraindication for PSW application, especially metallic implants, pacemakers, lack of sensitivity, or tumor.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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121 participants in 3 patient groups, including a placebo group

High dose PSW groups

Experimental group

Description:

The treatment was performed with 2 devices named Diatermed II (Carci, São Paulo, SP, Brazil), previously calibrated, carrying frequency of 27.12MHz, peak power of 250W, and pulse duration of 400µs. All these parameters are predetermined in the device according to the manufacturer. We used the maximum power provided by the machine in a pulsed form with a pulse frequency of 145Hz, resulting in a mean power of 14.5W. These settings were based on the fact that applications with mean power below 20W minimize the thermal effects

Treatment:

Device: Pulsed short wave

Placebo

Placebo Comparator group

Description:

A placebo group was also established, in which the PSW device was turned on but kept in stand-by mode during 19 minutes without any electrical current being applied in the patients

Treatment:

Device: Pulsed short wave

Control

No Intervention group

Description:

The control group was composed of patients that were not submitted to any form of treatment and all patients were instructed to maintain their daily activities