Modalities

Heat therapy (thermotherapy)

Thermotherapy involves the application of heat to body tissues to increase circulation, metabolic rate, and tissue extensibility. It is commonly used to manage pain, muscle spasm, and joint stiffness in subacute and chronic conditions.

Types of thermotherapy

• Hot packs: Moist heat applied with Hydrocollator packs wrapped in towels
• Paraffin wax baths: Commonly used for distal extremities (e.g., hands, feet)
• Fluidotherapy: Dry heat through suspended cellulose particles
• Shortwave diathermy: Deep heating through electromagnetic energy

Clinical indications

• Muscle spasm and guarding
• Joint stiffness and decreased ROM
• Chronic musculoskeletal pain
• Increased blood flow for tissue healing

Application parameters

• Hot packs: 15-20 minutes, use 6-8 towel layers to avoid burns
• Paraffin: 10-15 minutes using the dip-wrap method (5-10 dips)
• Diathermy: Typically 20 minutes for deep heating effects

Contraindications

• Acute inflammation or bleeding
• Malignancy in treatment area
• Deep vein thrombosis (DVT)
• Open wounds or infections

Precautions

• Impaired sensation or mentation: check the skin frequently and monitor closely for signs of overheating, since heat can still be applied cautiously when the patient retains some sensory feedback.

Contraindication vs. precaution: a contraindication means you don’t apply the modality at all. A precaution means you can proceed, but only with extra monitoring or modified parameters - impaired sensation is a precaution rather than an outright stop for most thermal and electrical modalities. If a patient shows an adverse response (burning, unusual pain, skin or color changes) during any modality, stop treatment and report the finding to the supervising PT rather than modifying the plan of care yourself.

Cold therapy (cryotherapy)

Cryotherapy is the application of cold to reduce inflammation, pain, and muscle spasm, particularly in acute and post-surgical conditions. Patients typically feel sensations in this order: cold, burning, aching, and numbness (CBAN) - numbness indicates that analgesia has been achieved.

Types of cryotherapy

• Ice massage: Applied directly on a localized area, fastest tissue cooling 5-8 minutes
• Ice packs: Applied with a barrier for 10-15 minutes
• Cold immersion baths: Typically 50-60°F (10-15°C), 10-15 minutes
• Vapocoolant sprays: Used for muscle spasm, applied with 2-4 sweeps

Clinical indications

• Acute musculoskeletal injuries
• Edema control
• Spasticity management
• Localized pain relief

Contraindications

• Cold hypersensitivity or intolerance
• Raynaud’s disease
• Open or infected wounds
• Peripheral vascular disease (PVD)

Precautions

• Impaired sensation or cognition, hypertension, and superficial nerve locations (e.g., over the fibular head) - monitor closely and reduce treatment time as needed.

Therapeutic ultrasound (US)

Ultrasound uses high-frequency sound waves to produce thermal or non-thermal effects for tissue healing, pain reduction, and increased extensibility of soft tissues.

Clinical indications

• Chronic tendinopathies
• Ligament sprains and muscle strains
• Joint contractures
• Scar tissue management

Application parameters

• Frequency:
  • 1 MHz: For deep tissue (up to 5 cm)
  • 3 MHz: For superficial tissue (1-2 cm)
• Duty cycle:
  • 100% (Continuous): Thermal effects
  • 20-50% (Pulsed): Non-thermal, acute phase
• Intensity:
  • 0.5-1.0 W/cm²: Superficial
  • 1.0-2.0 W/cm²: Deep tissues
• Duration:
  • 5-10 minutes per treatment area

Contraindications

• Over malignant areas, reproductive organs
• Over pacemakers, eyes, or carotid sinus
• During pregnancy (lumbar/abdominal regions)
• Over bony prominence, growth plates, and acute bony fracture.

Precautions

• Decreased sensation or circulation, and use over metal implants or healing fractures only with reduced intensity and close monitoring.

Electrical stimulation (E-stim)

E-stim involves the use of electrical currents to stimulate nerve or muscle function for various therapeutic goals.

Types and indications

• TENS (transcutaneous electrical nerve stimulation): Pain modulation via gate control theory (high rate), endogenous opioid theory (EOT) low rate.
• NMES (neuromuscular electrical stimulation): Used for muscle re-education and strengthening; it uses a biphasic waveform that creates zero net charge, reducing skin irritation.
• IFC (interferential current): Uses an interference between two medium-frequency (kHz range, about 4,000 Hz) currents produces a low frequency (beat) current that will be induced in the deep tissues. Effects are similar to TENS
• HVPC (high-voltage pulsed current): Wound healing - negative polarity during the inflammatory/debridement phase, positive polarity during the proliferative/epithelialization phase; edema control uses negative polarity.
• DC (direct current): Iontophoresis for transfer of ions in solution edema control with negative polarity, and pain control positive polarity. Treatment is dosed in milliamperes/min (mA/min)

Parameters

• TENS: 50-150 Hz, 50-80 µs, continuous mode (gate theory)
• TENS: 1-4 Hz, 150-220 µs, low pulse mode (endogenous opioid theory)
• IFC: 2 medium-frequency channels (about 4,000 Hz, with the second set slightly higher, e.g., 4,001-4,250 Hz) creating an interference (beat) frequency of 1-250 Hz in deeper tissues.
• NMES: 35-50 Hz, 200-400 µs, 1:5 duty cycle
• HVPC: 100-150 V, 50-100 Hz
• Ionto: Milliamperes/min (mA-min), 40-80 (commonly 40)

Contraindications

• Cardiac pacemakers or defibrillators
• Unstable arrhythmias
• Thrombophlebitis or DVT
• Pregnancy (abdomen/lumbar)
• Electrode placement over the carotid sinus (anterior neck) or over the eyes

Precautions

• Impaired sensation or cognition - use only with caution and clear clinical indication.

Biofeedback

Biofeedback uses sensors to translate a physiological signal the patient can’t normally perceive into real-time visual or auditory feedback, so the patient can learn to control it. The most common form in physical therapy is EMG (surface electromyography) biofeedback, which displays muscle activity.

Clinical indications

• Muscle re-education: feedback helps a patient recruit a weak or inhibited muscle (e.g., the quadriceps after knee surgery)
• Muscle relaxation / down-training: feedback helps reduce overactivity in a tense or spasming muscle
• Neuromuscular retraining after stroke or other neurological injury
• Pelvic floor retraining for incontinence

Precautions

• Skin irritation or breakdown under the surface electrodes - inspect the skin and reposition as needed
• Impaired cognition or attention can limit the patient’s ability to use the feedback
• Biofeedback trains voluntary control; it does not replace the strengthening or motor training in the plan of care

Intermittent pneumatic compression

An intermittent pneumatic compression device inflates and deflates an air-filled sleeve around a limb in cycles, applying external pressure that moves fluid proximally out of the extremity.

Clinical indications

• Edema management in the extremities
• Lymphedema (as part of a complete decongestive program)
• Venous insufficiency and chronic venous stasis
• DVT prophylaxis in immobile or post-surgical patients (mechanical prevention of clot formation)

Contraindications

• Acute DVT - compressing a limb with a known or suspected acute clot risks dislodging it
• Acute infection or cellulitis in the limb
• Uncompensated (acute) heart failure - shifting fluid centrally can overload the heart
• Compartment syndrome

Precautions

• Impaired sensation or cognition - the patient may not report pain or numbness under the sleeve
• Peripheral arterial disease - excessive pressure can further compromise arterial flow
• Fragile or broken skin under the sleeve
• Monitor for increased pain, numbness, or color changes, and report them to the supervising PT

Continuous passive motion (CPM)

A CPM device is a mechanical motion device: a motorized frame that moves a joint, most often the knee, passively through a preset arc of motion while the patient stays relaxed.

Clinical indications

• Maintaining joint range of motion after surgery or after manipulation under anesthesia, when the surgeon’s protocol calls for it
• Limiting joint stiffness while active motion is not yet possible

The APTA clinical practice guideline recommends against routine CPM after a primary, uncomplicated total knee arthroplasty; when CPM is used, a documented complication (such as stiffness) should justify it.

Precautions

• Align the device’s axis with the patient’s joint axis and secure the limb so it moves only in the intended plane
• Stop and report increased pain, bleeding or wound drainage, numbness, or skin pressure areas to the supervising PT
• Change the range, speed, or wear time only as the PT’s plan of care directs

Traction

Mechanical traction is used to relieve pressure on the spinal structures and improve joint mobility.

Clinical indications

• Herniated discs
• Nerve root impingement
• Hypomobility or facet joint dysfunction

Parameters

• Static/intermittent:
  • Static best for disc and nerve root impingement
  • Intermittent best for hypomobility
• Cervical traction:
  • Initial force: 10-15 lbs
  • Maximum: 30 lbs
  • Angle: 15-20° of flexion for the upper cervical spine, using an over-the-door halter with the patient seated
  • Angle: 25-35° of flexion for the lower cervical spine, using an occipital halter with the patient supine
  • Duration: 10-15 minutes
• Lumbar traction:
  • Initial force: 25% of body weight
  • Maximum: 50% of body weight
  • Supine position best for upper lumbar segments and hypomobility
  • Prone position best for lower lumbar and disc herniation
  • Duration: 15-20 minutes

Contraindications

• Acute cervical or lumbar injuries
• Spinal infections or malignancy
• Hypermobility or instability
• Severe osteoporosis

Precautions

• Claustrophobia or anxiety with the halter/harness, temporomandibular joint (TMJ) dysfunction with cervical traction, and pregnancy - monitor tolerance and adjust force as needed.