1. Thermal Agents 🔥

Superficial Heat (Hot Packs, Paraffin)

Indications:

Subacute/chronic inflammation
Muscle spasm relief
Pain reduction
Increase tissue extensibility

Contraindications:

Acute inflammation
Impaired sensation
Over malignancy
Bleeding disorders

Cryotherapy (Cold Packs, Ice Massage)

Effects (CBAN): Cold-induced vasodilation (after vasoconstriction), Burning sensation first then numbness, Analgesic effect, Numb after 5-10 mins

Contraindications: Raynaud's disease, Cryoglobulinemia, Cold hypersensitivity, Impaired circulation

Deep Heat - Ultrasound

1 MHz: Deep penetration (3-5 cm) - for larger muscles
3 MHz: Superficial (1-2 cm) - for tendons, ligaments
Continuous mode: Thermal effects (50-100% duty cycle)
Pulsed mode: Non-thermal/mechanical effects (20% duty cycle)

2. Electrical Stimulation ⚡

TENS (Transcutaneous Electrical Nerve Stimulation)

Mode	Frequency	Mechanism
Conventional (Hi-TENS)	50-150 Hz	Gate Control Theory
Acupuncture (Lo-TENS)	1-10 Hz	Endorphin Release
Burst Mode	Bursts of 100 Hz	Both mechanisms

NMES & Iontophoresis

NMES: 25-50 Hz, on:off ratio 1:3 to 1:5 - for muscle strengthening
Iontophoresis: Uses direct current to drive ions into tissue
Dexamethasone (-): Anti-inflammatory - placed under negative electrode
Lidocaine (+): Local anesthetic - placed under positive electrode

3. Mechanical Modalities ⚙️

Traction

Cervical: 10-15 lbs to start, up to 25-35 lbs
Lumbar: 25-50% body weight minimum
Intermittent: 30-60 sec on/off - for disc conditions
Static: For muscle spasm relief

Compression

Reduce edema and venous stasis
Intermittent: 30-80 mmHg, 3:1 ratio
Contraindicated in DVT, CHF

Pro Tip para sa Board Exam

Remember polarity for iontophoresis! "Like repels like" - positive drugs under positive electrode, negative drugs under negative electrode. For ultrasound: 1 MHz = deep (1 deep), 3 MHz = superficial (3 sounds like "surface").

Physical Agents