At which frequencies is therapeutic ultrasound almost always applied?

Therapeutic ultrasound is primarily applied at frequencies that range from 1 MHz to 3 MHz, with 1 MHz being more commonly used for deeper tissues and 3 MHz for more superficial tissues. The choice of frequency depends on the depth of penetration needed for effective treatment.

At 1 MHz, the ultrasound penetrates tissues to a depth of approximately 5 cm, making it suitable for conditions affecting deeper structures, such as muscles and joints. On the other hand, the 3 MHz frequency targets more superficial layers, such as the dermis and subcutaneous fat, typically penetrating to around 1-2 cm. This ability to customize treatment based on the condition and tissue depth is essential for therapeutic effectiveness.

Other frequencies like 500 kHz or 4 MHz are less common in therapeutic settings. Frequencies like 500 kHz might be used for specific applications but are not standard in therapeutic ultrasound practice. Similarly, while 4 MHz could theoretically offer benefits for very shallow tissues, it is not typically utilized in standard therapeutic protocols. The focus remains on 1 MHz and 3 MHz due to their established efficacy and specific applicability in chiropractic care.