Sports Medicine: Just the Facts

ULTRASOUNDPRECAUTIONS

• Ultrasound is typically avoided in the acute stages of
  an injury due to concerns that it may aggravate bleed-
  ing, tissue damage, and swelling.


• The subacute situation may be different, as many feel
  that ultrasound may speed healing and the resolution
  of symptoms in the later stages of injury.

PHONOPHORESIS

• Ultrasound may be used to deliver medication into tis-
  sues. The active substance is mixed into a coupling
  medium, and ultrasound is used to drive (phonophores)
  the material through the skin.


• Phonophoresis with corticosteroids is frequently used
  in sports medicine.


• Clinical studies are conflicting.
  •A comparison of phonophoresis of 0.05% fluocinon-
  ide with ultrasound alone. At 1.5 W/cm^2 both treat-
  ments were found beneficial, but indistinguishable in
  their effects on superficial musculoskeletal conditions
  (Klaiman et al, 1998).


• Another study did not find lidocaine and corticos-
  teroid phonophoresis more effective than the same
  treatment with an inert coupling agent (Moll, 1977).

CONTRAINDICATIONS
•Fluid-filled areas (i.e., eye and the pregnant uterus)
•Growth plates, immature or inflamed joints (Dussick
et al, 1958; Weinberger et al, 1988; 1989)

• Acute hemorrhages, ischemic tissue, tumors, laminec-
  tomy sites, infections, and implanted devices such as
  pacemakers and pumps


• Caution:Relatively contraindicated near metal plates
  or cemented artificial joints, as the effects of localized
  heating (Brunner et al, 1958; Gersten, 1958; Skoubo-
  Kristensen and Sommer, 1982) or mechanical forces
  on prosthetic-cement interfaces is not well known.

SHORTWAVE DIATHERMY

HEATS BYCONVERSION

• Shortwave diathermy (SWD) uses electromagnetic
  (EM) energy to interact with tissue and produce heat.


• Both thermal and nonthermal effects are possible.
  •Tissue warming is produced by two processes:
  
  
  1. Resistive heating
  
  
  2. Degradation of molecular oscillatory motions that
     EM waves induce when they interact with tissue.
  
  
  
  


• SWD is the dominant EM diathermy in sports medi-
  cine, albeit relatively rarely used in comparison the
  other heating modalities.


• Most devices operate at 27.12 MHz. The U.S. Federal
  Communications Commission also approves frequen-
  cies of 13.56 and 40.68 MHz for use.

MECHANISM

• An SWD machine is a signal generator that uses either
  inductive or capacitive electrodes to deliver energy to
  the body.


• Inductive electrodes act as an antenna, and the body
  absorbs energy from an EM field produced by the
  short-wave machine.
  •With capacitive electrodes, the portion of the body
  being treated is placed in series between the elec-
  trodes and serves as the dielectric (resistance)
  between two plates of a capacitor.


• Inductive applicators induce currents that preferen-
  tially flow in water-rich tissues such as muscles that
  are highly conductive.
  •Capacitive applicators, on the other hand, heat poorly
  conductive substances, such as fat preferentially
  (Kantor, 1981).


• SWD can increase subcutaneous fat temperatures by
  15 °C and intramuscular temperatures at depths of
  4 to 5 cm by 4 to 6°C (Lehmann, DeLateur, and
  Stonebridge, 1969; Draper et al, 1999).

TECHNIQUE

•Two common inductive applicators are typically uti-

lized (pads or drums).

•Pad applicators are moderately flexible mats that con-

tain a coil.

• Drum applicators are characterized by fixed coils and
  hinges.

INDICATIONS

• Heating in tissues that are either too deep or too exten-
  sive to be treated by other modalities, e.g., the low
  back, the knee.

PRECAUTIONS ANDCONTRAINDICATIONS/SAFETY

•Jewelry is removed.

•Treatment is performed on nonconductive tables.

• Contraindications include metal implants or electrical
  devices (e.g., joints, pacemakers, pumps, and metallic
  intrauterine devices), contact lenses, and the menstru-
  ating or pregnant uterus.
  •Treating the immature skeleton is generally not rec-
  ommended and has not been well studied.

LOW-POWER AND PULSED

ELECTROMAGNETIC FIELD

HEATS BYCONVERSION

• Nonthermal effects can be obtained and tissue heating
  avoided altogether by using low-power fields deliv-
  ered in either continuous or pulsed modes.


• Research offers little to support the specificity or cer-
  tainty of benefits.

408 SECTION 5 • PRINCIPLES OF REHABILITATION