Therapeutic Ultrasound

Therapeutic ultrasound is a trusted treatment method in physiotherapy that uses high-frequency sound waves to heal injured tissues, relieve pain, and restore movement. With decades of clinical use, it remains a core modality for treating soft tissue injuries and chronic musculoskeletal conditions.

What is Therapeutic Ultrasound?

Therapeutic ultrasound delivers sound waves at frequencies between 0.7 and 3.3 MHz. These waves pass through the skin and penetrate soft tissues, causing vibrations at the cellular level. Depending on the settings used, ultrasound therapy can create both heat and mechanical stimulation — both of which accelerate tissue repair and reduce inflammation.

How Therapeutic Ultrasound Works

1. Thermal Effects

When used in continuous mode, ultrasound causes deep heating, which leads to:

• Increased blood circulation
• Relaxation of muscles
• Reduction in joint stiffness
• Enhanced flexibility in soft tissues
• Pain relief due to decreased nerve sensitivity

2. Non-Thermal (Mechanical) Effects

When used in pulsed mode, ultrasound has non-heating effects that support healing:

• Cavitation – Small gas bubbles form and oscillate, encouraging tissue repair
• Acoustic Streaming – Fluid movement at the cellular level increases cell permeability and nutrient exchange
• Stimulates fibroblast activity and protein synthesis
• Reduces swelling and inflammation in the early phase of injury

Indications: What Conditions Can Be Treated?

Ultrasound therapy is used to treat a variety of conditions:

Modes of Application

1. Continuous Ultrasound

• Delivers a constant stream of sound waves
• Produces thermal effects
• Suitable for chronic injuries, joint stiffness, scar tissue

2. Pulsed Ultrasound

• Intermittent wave transmission
• Non-thermal, mechanical effects dominate
• Suitable for acute injuries or inflammation 

3. Phonophoresis

• Ultrasound is used to drive topical medications (like anti-inflammatories) deep into tissues
• Enhances drug absorption and reduces systemic side effects

Key Parameters Used in Therapy

• Frequency:
  • 1 MHz: For deeper tissues (up to 5 cm)
  • 3 MHz: For superficial tissues (up to 2 cm)
     
• Intensity:
  • Usually between 0.1 and 2.0 W/cm²
  • Higher intensity = more heat
     
• Duty Cycle:
  • Continuous mode: 100% duty cycle for heat
  • Pulsed mode: 20% or 50% for non-thermal healing
     
• Treatment Time:
  • Generally 5–10 minutes per target area
     
• Application Method:
  • Transducer head moved in circular or linear motions
  • Ultrasound gel applied to eliminate air between the probe and skin 

Safety Guidelines and Contraindications

 Safe When:

• Administered by certified physiotherapists
• Parameters are adjusted based on the injury type and location
• Applied with correct technique and duration

 Avoid Ultrasound Over:

• Eyes
• Abdomen during pregnancy
• Reproductive organs
• Infected or cancerous areas
• Epiphyseal (growth) plates in children
• Over metal implants (with caution)

Clinical Expectations: What Happens in a Session?

• The therapist applies gel over the target area.
• The ultrasound transducer (head) is moved slowly in a circular motion.
• You might feel mild warmth or nothing at all — both are normal.
• Sessions typically last 5–10 minutes.
• Improvement is often observed after a few sessions, especially when combined with other therapies. 

Ultrasound vs Other Modalities

Advantages of Ultrasound Therapy

• Non-invasive and safe
• Speeds up natural healing
• Enhances the effectiveness of other treatments
• Useful for both acute and chronic injuries
• Customizable for each patient
  
   

Summary

Therapeutic ultrasound is a trusted, safe, and evidence-supported modality in physiotherapy that helps heal soft tissues, reduce pain, and improve function. When used correctly, it complements manual therapy, exercises, and other treatment techniques to accelerate patient recovery.

Book Your Session with TheTruePal Physiotherapists

If you're dealing with an injury, chronic pain, or reduced mobility, Therapeutic Ultrasound could be a game-changer in your recovery.Book Physiotherapy with Truepal

FAQs

1. What is therapeutic ultrasound used for in physiotherapy?

Therapeutic ultrasound is used to treat soft tissue injuries, reduce inflammation, promote tissue healing, and improve mobility. It's commonly applied for conditions like tendonitis, ligament sprains, muscle strains, joint stiffness, and scar tissue management.

2. Is ultrasound therapy safe?

Yes, when applied by a trained physiotherapist, ultrasound therapy is considered very safe. The machine settings are customized to your condition, and the therapy is non-invasive. However, it is avoided over certain areas like the abdomen during pregnancy, near tumors, or over infected tissue.

3. How many sessions of ultrasound therapy will I need?

The number of sessions depends on the severity of your condition. Most patients start to notice improvement after 4–6 sessions. For acute injuries, fewer sessions may be needed, while chronic conditions may require a longer treatment plan alongside exercises and manual therapy.

4. Does ultrasound therapy hurt?

No, ultrasound therapy is typically painless. You may feel a mild warmth or no sensation at all. If there’s any discomfort, the therapist will adjust the intensity or technique to ensure your comfort during the session.

5. Can ultrasound therapy be combined with other treatments?

Absolutely. Ultrasound is often used in combination with physiotherapy exercises, manual therapy, dry needling, or TENS therapy to speed up recovery. It enhances blood flow and reduces inflammation, making other treatments more effective.

6. How soon will I see results from ultrasound physiotherapy?

Some patients feel relief after the first few sessions, while others may notice gradual improvement over time. Consistency and a tailored treatment plan—especially when combined with strengthening or mobility exercises—typically yield the best results.