Sports injuries are injuries that occur when engaging in sports or exercise. Sports injuries can occur due to overtraining, lack of conditioning, and improper form or technique. They can be acute or chronic in nature.  Bruises, strains, sprains, tears, and fractures can result from sports injuries. Soft tissues like muscles, ligaments, tendons, fascia, and bursae are commonly affected. Managing a sports injury includes the prevention, diagnosis, treatment and rehabilitation of injury and illness; the enhancement of performance through training, nutrition and psychology; and ethical issues involved in sports ⁽¹⁾. Availability of a range of evidence-based methods helps a sports physiotherapist in managing and preventing an injury with greater ease such method is Iontophoresis.

Iontophoresis is a non-invasive technique ⁽²⁾. This method has been used since the 1800’s. The method is based on the entry of charged substances into the body for therapeutic purposes by the means of direct current [D.C.]. It is based on the principle of like poles repel and unlike poles attract each other. The ions are repelled into the skin where they recombine with existing ions and radicals. The ideal concentration remains between 1 – 5 %. Low level amperage [intensity] is best for similar reasons. Parameters of application involves electrode placement and size; polarity which should be same of the ion and the electrode; current amplitude which should not be more than 4 milli ampere (mA) and the treatment time which should be between 10 to 20 minutes.

Significance of Cathode and Anode

Cathode [Negative Electrode]	Anode [Positive Electrode]
Produces Alkaline Reaction[Strong Alkali] Under the Skin i.e. NaOH Is Produced	Produces Acidic Reaction [Weak Acid] Under the Skin
Releases Hydrogen	Releases Oxygen
It Is Sclerolytic i.e. Acts As a Softening Agent	It Is Sclerotic i.e. Acts As a Hardening Agent
Used In Management Of Scars, Burns And Keloids	Improves Healing And Has An Analgesic Effect

 

There are certain factors affecting Iontophoresis:

1. Direct current is to be used.
2. Physiochemical variables: they are the charge, size of ion and structure of drug.
3. Formulation factor: it comprises of the pH, amount of drug and viscosity. The drug should be water soluble, low dose and ionisable with the charge density.
4. Biological factor: i.e. thickness, permeability and presence of pores. Sweat glands are the most significant path for conduction of charges into the skin.
5. Electro osmosis transport: this is how the ions travel through the membrane which depends on the cathode or anode.

Dosage of Medication

• Dosage is expressed in milliampere-minutes (mA-min)
• Total drug dose delivered (mA-min) = current X treatment time
• Typical iontophoresis drug dose is 40 mA-min

Methods of Application

Mainly 3 methods used into practice are mentioned as follows ^(3,4,5): 

Method A

• The medicine is applied on the sterile gauze.
• Place the gauze on the electrode.
• Make sure the polarity corresponds with the medicine used.
• The electrodes are placed on the desired body part and treatment is given.

Method B

• The part to be treated is immersed in water.
• A gentle current pass through the water.
• Gradually and carefully the current is increased until a feeling of light tingling sensation.
• Mainly used to treat hyperhydrosis of hands and feet.

Method C

• It is the 24-hour Iontophoresis patch.
• The devices have a battery within the electrodes and deliver between 0.1 – 0.3 Ma for a period of 1 – 24 hours delivering a total dose of approx. 40 to 80 mA-min.
• The battery activates when the drug is applied to the electrode [patch] which is applied to the skin.
• Benefits are that it reduces skin irritation and provides prolonged drug delivery.

Application in Sports injuries

As mentioned, the method is used in wide variety of conditions initially in patients with hyperhydrosis, but since research and usage increased, it is used in almost all musculoskeletal conditions. Examples of successful applications of iontophoresis include treatment of inflammation/pain of muscles and tendons, including the Achilles tendon; relief of heel pain from bone spurs; controlling the pain of tennis elbow; relief of pain from rheumatoid arthritis of the knee; relief of pain associated with plantar fasciitis; an alternative to steroid injections for therapy of Carpal Tunnel Syndrome; treatment for scar and tendon adhesions; myofascial shoulder girdle syndrome; calcific trochantic bursitis ^(5,6,7)

A detailed list shows the condition; the polarity and concentration to be used as per the indication.

ION	POLARITY	INDICATIONS	CONCENTRATION[%]
Hyluronidase	Positive	Edema, Ankle Sprain	0.9
Acetate	Negative	Peri Articular Ossification	2.5-5
Copper	Positive	Fungal Infection	2.00
Dexamethasone Phosphate	Negative	Inflammation	0.40
Iodine	Negative	Scars; cutaneous Adherences; Stiffness of joints and Adhesive Capsulitis	1 to 5
Lidocaine	Positive	Local anasthetic;Joint Pain, Trigeminal Neuralgia	2.00
Magnesium	Positive	Muscle Relaxant; Vasodilator	0.25
Salicylate	Negative	Plantar Warts; Analgesic in case of Muscle Pain due to Rheumatoid arthritis; Periphlebitis, Osteo-arthritis	2.00
Tap Water	Negative/Positive	Hyperhydrosis	4 to 5
Zinc	Positive	Dermal Ulcer; Wounds	2 to 4
Glutamic Acid	Positive	Carpal Tunnel Syndrome	0.8 to 1
HydroCortisone	Positive	Anti Inflammatory in case of Arthritis; Tendinitis; Bursitis	1.00
Mecholyl	Positive	Vasodilator; Analgesic in case of Neuritis; Sprain; edema	0.3 to 0.5
Calcium	Positive	Post Traumatic Pain; Distortion; Neuralgia; Algodistrophic Syndromes	2.00
Chlorine	Negative	Scar Tissue, Adhesions	2.00
Lithium	Positive	Gout	1 to 3
Dexamethasone	Negative	Parasthesia; Tempomandibular Trismus; Collagen Diseases	0.40
Silver	Positive	Rheumatoid arthritis of Hand	0.30
Predinesolon	Negative	Rheumatoid Arthritis, Adrino Cotico Insufficiency	1 to 5
Coltramyl	Positive	Contractures	0.04
Voltaren	Negetive	Inflammation	0.75

 

Every electrotherapeutic modality has few precautions to be followed; in case of iontophoresis it includes Positioning of the Patient Should be proper and it Should never be weight bearing on Electrode; Two chemicals should not be used under the same electrode; One Sterile Gauze for One Patient or Proper washing of electrode or the electrode cover. ; Administration of drug should be avoided as per conditions such as if the patient is allergic to sea food iodine should not be used; administration of hydrocortisone in patients with G.I.T problems should be avoided. ⁽⁵⁾

There are few contraindications and dangers involved. Contraindications include Ischemic Conditions; Unreliable Patients; Electrically sensitive Implanted Devices Such as Cardiac Pacemakers; Hypersensitive Patients To Specific Drugs; Pregnancy. Dangers include such as Electrolytic Burn which may be due to poor contact; chemical burn due to accumulation of acid or alkali; increased or decreased skin sensation. ⁽⁵⁾

References

1.  Brukner P. Brukner & Khan's clinical sports medicine. North Ryde: McGraw-Hill; 2012.

2.  Eljarrat-Binstock E, Domb AJ. Iontophoresis: a non-invasive ocular drug delivery. Journal of Controlled Release. 2006 Feb 21;110(3):479-89.

3. Delgado-Charro MB, Guy RH. Transdermal iontophoresis for controlled drug delivery and non-invasive monitoring. STP Pharma Sciences. 2001;11(6):404-14.

4. Leboulanger B, Guy RH, Delgado-Charro MB. Reverse iontophoresis for non-invasive transdermal monitoring. Physiological measurement. 2004 Apr 20;25(3):R35.

5.  Cameron MH. Physical Agents in Rehabilitation-E Book: An Evidence-Based Approach to Practice. Elsevier Health Sciences; 2017 Sep 6.

6.  Osborne HR, Allison GT. Treatment of plantar fasciitis by LowDye taping and iontophoresis: short term results of a double blinded, randomised, placebo controlled clinical trial of dexamethasone and acetic acid. British journal of sports medicine. 2006 Jun 1;40(6):545-9.

7. Kilfoil RL, Shtofmakher G, Taylor G, Botvinick J. Acetic acid iontophoresis for the treatment of insertional Achilles tendonitis. Case Reports. 2014 Jul 23;2014:bcr2014206232.