11. ELECTRICAL SHOCK WAVE THERAPY 23-24.pdf

EXTRACORPOREAL SHOCKWAVE THERAPY (ESWT) ELECTROPHYSICAL AGENTS Degree of Physiotherapy San Pablo-CEU University 2023-2024 OUTLINE 1. DEFINITION AND CLINICAL CHARACTERISTICS. 2. CLASSIFICATION 1. FOCUSED. 2. RADIAL. 3. PARAMETERS 4. BIOLOGICAL AND THERAPEUTICAL EFFECTS. 5. DOSIMETRY. 6. APPLICATI...

EXTRACORPOREAL SHOCKWAVE THERAPY (ESWT) ELECTROPHYSICAL AGENTS Degree of Physiotherapy San Pablo-CEU University 2023-2024 OUTLINE 1. DEFINITION AND CLINICAL CHARACTERISTICS. 2. CLASSIFICATION 1. FOCUSED. 2. RADIAL. 3. PARAMETERS 4. BIOLOGICAL AND THERAPEUTICAL EFFECTS. 5. DOSIMETRY. 6. APPLICATION. 7. INDICATIONS AND CONTRAINDICATIONS. 2 ESWT DEFINITION • Application of pressure mechanical waves outside of the body (extracorporeal) that violently impact (shock) bilogic tissues for therapeutic purposes (Rompe, 2002). • A shock wave is defined as a low-to-large-amplitude wave formed by the sudden mechanical compression of the medium through which the wave moved. 3 ESWT DEFINITION • Sonic waves producing very high peak pressure in a very reduced period. • Max. Duration time= 10ns • Pressure: 100 MPa or 500 bar. (10 bar= 1 MPa) • Frequency= 16 Hz-20MHz. 4 ESWT CLASSICATION (PROPAGATION PATTERN) • FOCUSED (conversion of electrical to mechanical energy) – ELECTROHYDRAULIC GENERATORS. – ELECTROMAGNETIC GENERATORS – PIEZOELECTRIC GENERATORS • RADIAL (pneumatic principle) – BALLISTIC GENERATORS 5 ESWT CLASSIFICATION • FOCUSED ESWT (FSWT or f-ESWT). – First ESWT produced. EXTRACORPOREAL SHOCKWAVE THERAPY – High-energy density which converge in one point. – Mainly used in pseudoarthrosis, lithotripsy and delayed fracture consolidation. – Image guiding system (ecography/radiography). • RADIAL ESWT (RSWT or r-ESWT). – Low-energy density, pneumatic system – Commonly used in physiotherapy. 6 APPLICATOR TYPE AND COUPLING MEDIA • A coupling medium is required for mechanical energy trasmission and absorption. • Adjustable dome membranes filled with gas, water, gel are used with focused-type applicators. • For radial-type applicators aquasonic gel is used. standard 7 FOCUSED ESWT GENERATORS Cristal de cuarzo SiO2 (bióxido de silicio) O= Si++ Si++ O= O= Si++ • PIEZOELECTRIC . – Similar to ultrasound – 1000 cristals in a concave container (spherical piezoelectrical crystal). – High voltage applied to the crystal causes it to expand and collapse, generating the ESWT in the surrounding water medium. 8 RADIAL ESWT • Pneumatic system to which a handheld pistol-like applicator is attached with a cable. • No image guiding system because of the radial or divergent projection of the waves. Applicator of 15 mm 9 RADIAL ESWT • Generator consists of compressed air rapidly accelerating a projectile which hits the impact surface of the applicator and causes a shock wave. • Different applicators: – With direct beam. – For muscle and connective tissues. – Acupuncture points – Plane waves 10 RADIAL APPLICATORS TENDINOPATHIES 11 ESWT PENETRATION 12 WAVEFORM AND PARAMETERS • WAVEFORM: • Compressive phase (P+) FSWT RSWT • Tensile phase (P-) • RSWT present much lower P+ and P- and much longer pulse duration. • r-ESWT higher rise time and longer pulse duration. 13 WAVEFORM AND PARAMETERS • ENERGY AND ENERGY FLUX DENSITY: • Mechanical energy in ESWT is FSWT RSWT measured in milijoules. • Energy flux density (EFD): Amount of mechanical acoustic energy per unit area per shock. EFD= E/A. • Millijoules per square millimeter (mJ/mm2) • f-ESWT more EFD: More energy over a smaller area. 14 MAXIMUM ENERGY FLUX DENSITY 15 COMPARISON BETWEEN FOCUSED AND RADIAL ESWT Parameters f-ESWT r-ESWT GENERATOR Electrohydraulic Electromagnetic Piezoelectric Ballistic PROPAGATION Focused (convergent) Radial (divergent) PENETRATION DEPTH Deep at focal point (>5cm) Superficial on skin surface (<5cm) LOCALIZATION METHOD Imagine guided Clinical focusing/palpation COMPRESSIVE PRESSURE Up to 120 MPa Up to 0.5 MPa TENSILE PRESSURE Aprox. 1/10 of Pp+ Aprox. 1/10 of Pp+ 16 COMPARISON BETWEEN FOCUSED AND RADIAL ESWT Parameters f-ESWT r-ESWT RISE TIME < 0.1 μs <10 μs PULSE DURATION < 0.5 μs < 500 μs ENERGY FLUX DENSITY Up to 2 mJ/mm2 Up to 0.5 mJ/mm2 COUPLIG MEDIUM Fluid water or gas-filled balloon Thin layer of aquasonic gel APPLICATOR Bulkier and more difficult to manipulate Smaller and easier to manipulate LOCAL ANALGESIA Often required to prevent pain Smaller, focused, deeper areas Not required INDICATION Larger, less focused and superficial areas. 17 BIOLOGICAL AND THERAPEUTICAL EFFECTS • MECHANICAL EFFECT reinforced: – Cavitation phenomenon – Reflection phenomenon. • Inflammatory reaction reactivation and tissue regeneration. • Vasodilation • Calcium deposits absorption. • Analgesia. Bone Muscle Interference Emitter 18 DOSIMETRY • ROMPE et al, 1998. – Low (<0’28 mJ/mm2). Analgesia. – Medium (0’28-0’6 mJ/mm2). Reactivation. – High (>0’6 mJ/mm2). Calcifications. Rompe JD, Kirkpatrick CJ, Kullmer K, et al. Doserelated effects of shock waves on rabbit tendo Achilles. J Bone Joint Surg (Br) 1998;80:546-52. 19 DOSIMETRY • LESS PRESSURE AND NUMBER OF SHOCKS USING APPLICATORS OF LESS THAN 15 MM RADIUS. • HIGH FREQUENCY MORE TOLERATED. • MORE PRESSURE AND MORE NUMBER OF SHOCKS FOR CHRONIC INJURIES. 20 DOSIMETRIC EXAMPLES OF ESWT Parameters f-ESWT r-ESWT NUMBER OF SHOCKS PER TREATMENT 1.800 2.000 SHOCK FREQUENCY 3 Hz 5 Hz ENERGY FLUX DENSITY (EFD) 0.38 mJ/mm2 0.18 mJ/mm2 DOSE PER TREATMENT (D) EFD x 1800= 684mJ/mm2 EFD x 2000= 360mJ/mm2 PRESSURE NA 4 bar NUMBER OF 2 TREATMENTS TOTAL ENERGY DOSE D x 2 = 1368 J/mm2 3 D x 3 = 1080 J/mm2 21 APPLICATION • 1ª PHASE. Tissue preparation – Manual Therapy and Kinesiotherapy: ACTIVE HEATING. • 2ª PHASE. ESWT Application – Select application points. – Select pressure/energy, frequency and number of shocks. – Pistol-like applicator fixed but changing direction. – Pistol-like application moving in specific belly muscle. • 3ª PHASE. Calm PHASE. – Thermal continuos Ultrasound – To facilitate the liquid excess and calcium salts reabsorption. 22 APPLICATION 23 INDICATIONS • CHRONIC TENDINOPATHY. • SOFT TISSUES CALCIFICATIONS. • PLANTAR FASCIOPATHY. • MYOFASCIAL TRIGGER POINTS • MUSCLE CONTRACTURES. • HEEL SPUR • NONUNION AND DELAYED-UNION BONE FRACTURE 24 CONTRAINDICATIONS • PREGNANCY. • TUMORS. • INFECTION AREA. • PACEMAKER. • EPIPHYSEAL PLATES. • OSTEOPOROSIS. • COAGULATION PROBLEMS AND BLOOD COAGULATION THERAPY • CORTICOID RECENT INFILTRATED TISSUES • GAS-FILLED TISSUES: LUNGS AND INTESTINE. • HOLLOW VISCERA. • VASCULAR FRAGILITY • ACUTE/SUBACUTE INJURY. 25 PRECAUTIONS • PAIN • ECCHYMOSIS • BRUISING • SWELLING. 26