Indiba radiofrequency (RF) applications are one of many Electrophysical Agents (EPAs) or Electrophysical Modalities which utilise the delivery of energy from an external source into the tissues. Historically, these were referred to as Electrotherapy Modalities – but the EPA terminology has been widely adopted in most countries globally over the last 10-15 years.

Whilst there are many different modalities available to the therapist, there are some fundamental issues which are common to all of them. Essentially, (a) a machine or device is employed to deliver energy to the tissues (b) the delivered energy will give rise to one or several physiological responses and (c) those physiological changes can be utilised to achieve therapeutic gain or benefit. This is a much simplified version of the electrophysical effects model (Watson 2020) and is represented in Figure 1 below. The model covers both theoretical (left to right) and clinically applicable (right to left) approaches.

The simplistic model covers all energy applications from TENS employed for pain relief through to Ultrasound used as a means to enhance healing in a damaged ligament – and all variations in between. Indiba devices deliver (radiofrequency) energy to the tissues and therefore they will follow an identical energy-effects pathway. Clearly Indiba, as a therapy application, is not the same as TENS or Ultrasound nor Laser/Photobiomodulation – each of these will have specific modes of action and optimal clinical applications. There is not any one modality (EPA) which is “best” at everything – despite some of the claims that are made! Each modality is capable of achieving a range of physiological and therefore clinical benefits – but they are not “equal” – either in the effects achieved, their magnitude nor their duration.

Indiba devices have been around for some decades – my own involvement with them has been over the last 15 years – and they were around way before I started investigating their physiological and clinical benefits. One of the main ‘confusion’ issues arises from the name employed for these applications. There is, as yet, no universal agreement as to the ‘official’ terminology. Some use TECAR (Transferencia Electra CApacitiva Resistiva). This has been a widely employed nomenclature though some companies now use TECAR as the name of a specific device (their trade name) – and therefore it has lost its generic applicability. CRET (Capacitive Resistive Electric Transfer) is a reasonable translation of the original Italian acronym and, at the present time, is probably the preferred generic modality name. Indiba is effectively a manufacturer of a device (range of devices) that deliver CRET/TECAR radiofrequency energy. This confusion is dealt with in some additional detail in Watson (2024).

Whatever the name is employed by the manufacturer or therapist, at the end of the day, the machine delivers a radiofrequency electric current directly to the tissues (reflected in one of the other names which has been employed – RFEC – Radio Frequency Electric Current therapy). The Indiba devices employ (all devices) radiofrequency at 448kHz though this frequency is not unique to Indiba family devices. Devices from other manufacturers often deliver a similar RF frequency most typically between 300kHz and 1MHz based on my evaluation of the published evidence.

It is not possible in this brief paper to go through all the effects and applications for Indiba based therapy, but this will summarise he key issues and evidence which are Indiba specific.

History
Radiofrequency applications have been employed in the therapy domain for at least 100 years. They were – historically – used as a means of heating the tissue. Shortwave based treatments (pulsed / continuous) employ a radiofrequency at around 27MHz – and thus much higher than the Indiba applications being considered here (typically 0.3 – 1.0 MHz with Indiba specifically at 0.448MHz). Radiofrequency application were reviewed in both acute and chronic clinical applications (Kumaran and Watson 2015; 2016). These narrative reviews considered a wide range of applications across the RF range, concluding that there was sufficient quality evidence to justify their use. Al-Mandeel and Watson (2020) considered a wide range of RF applications – and Indiba based therapies were sufficiently evidenced to justify their inclusion in that textbook review. Both Ribeiro et al (2018) and Beltrame et al (2020) provide reviews which concur with these overarching headlines.

Modality Differences
The key difference between Indiba based RF therapy applications and other historical RF (shortwave) is that the Indiba energy is delivered in direct contact with the patient – unlike shortwave or microwave energies which are delivered across an air gap. One might anticipate (from a theoretical perspective) that the effects of Indiba would be highly similar or almost identical to shortwave. High dose Indiba equating to continuous shortwave and low dose Indiba equating to pulsed shortwave. When tested – in both the lab and clinical environments – Indiba demonstrated a clear and significant advantage in terms of the effects achieved and their duration : Indiba generated stronger effects and much longer lasting effects. (Kumaran and Watson 2017; 2018a, b; 2019; 2020). Whilst the Indiba therapy is delivered in the kHz frequency range and the shortwave is in the MHz range, the fact that Indiba (whether is CAP or RES mode) is delivered with direct tissue contact constitutes a fundamental difference. The research (cited above) included a direct comparison with (pulsed) shortwave as part of the lab based work up. Indiba out performed shortwave without doubt.

Evidence Base and Clinical Scope
I have a database of research publications relating to EPAs which has been collected over the last 40 years (though many of the published papers go back way further). In that database, there are over 2500 publications which relate to the use of RF applications and a further 7300 on other aspects of bioelectric and electromagnetic research. This is no small volume – and is considerably stronger than several other, apparently well accepted, modalities. In a recent paper (Watson 2024) I looked at both Shockwave and Indiba type RF as ‘young’ modalities – and indeed, considered whether their emergence onto the clinical scene was another example of hype over evidence. Taking an objective approach – i.e. with no vested interest and with nothing to sell – I concluded that both modalities were supported by a robust evidence base, and whilst the interventions could not be a panacea for every problem that crosses the clinicians treatment couch (metaphorical for those of you who work in stables!), they deserved a place in the clinicians armoury and toolkit.

If one takes speciality areas within clinical practice where there is sufficient evidence to support Indiba in practice. 

Effects Models
It will be clear from the text in this summary paper that the mechanism by which the Indiba RF energy is able to achieve its effects will follow the same “model” as with all other EPAs. In gross modelling terms, I have constructed two simple pathways by which this can be shown to happen.

For each of the clinical applications identified in the previous section, a detailed – and evidenced – model (not illustrated here) has been developed – such that if one considers Indiba and acute pain relief or Indiba and enhanced repair of damaged musculoskeletal tissue, there is a distinct pathway by which we know how the treatment works. Again, it is not claimed that every element of the effects pathway has been identified – that would be a crass claim for any modality – but it does mean that there IS evidence to support the claims being made.

I must stress that this is NOT an advertising piece, an “advertorial” or paid for support of a manufacturer or a modality – it is an overview of the evidence as I currently see it. I have been collecting and evaluating such evidence for 40+ years and have developed such models in ultrasound, TENS, NMES (muscle stimulation) and myriad more. I am not suggesting that India is exclusive in that it is supported by evidence. I am stating that in my opinion, there IS sufficient and robust evidence of beneficial effect in human and animal based therapy domains. Furthermore, a substantial proportion of that evidence is directly related to Indiba based applications (rather than generic RF based evidence). Having looked at the available evidence in the public domain, many manufacturers and distributors of CRET / TECAR equipment do not have direct evidence (cell, animal, lab or clinical based) to support their specific device – they “borrow” research from manufacturers and researchers who have undertaken this work (like Indiba). The assumption is that the evidence is entirely transferable between devices which may operate with different parameters – e.g. frequency. This may, or may not, be a valid assumption.

Fashion or Fact
As I discussed in the 2024 paper evaluating both shockwave and CRET/TECAR based therapies (Watson 2024), new interventions follow a somewhat predictable pattern – with a peak of expectation in the early days followed by a period of disillusionment which ‘settles’ based on clinical uptake and the establishment of what is the most evidenced and seriously robust application range for the new ‘modality’ – this is reflected in the Gartner Hype Cycle. There are currently a wide range of applications for which Indiba (and other CRE/TECAR) are being tested and efficacy established. At some point in the future, there will be an established shortlist (or shorter list) of clinical presentations for which Indiba undoubtedly beats the opposition. The musculoskeletal domain (both human and animal) currently leads this grouping, and certainly if pain relief and pain management are considered alongside, this is a strongly evidenced package. The neurology (for example) has not yet reached this evidence level – neither has oncology nor urology. That does not mean that Indiba is
‘ineffective’ – but rather it is a reflection of the topics covered by clinical investigations and research programmes to date. Once again, this is not unique to Indiba – it was entirely the case for Ultrasound and Shockwave and all other modalities at some point in the past – it is the ‘normal’.

CRET based therapies (including Indiba) are a modern implementation of a radiofrequency (RF) based energy delivery. The use of RF energy with direct tissue contact delivery is not ‘new’ per se – but the modern technology enables the clinician to have far greater control over that energy delivery and thus have a far greater chance of beneficial outcome and ‘success’ that was the case early in the last century when longwave diathermy emerged.

Integrated Clinical Application
As a treatment approach, the use of EPAs is almost always at its optimum when employed in conjunction with other interventions – it is the “package of care” that provides the most effective and most robust clinical solution to a problem. It is highly unlikely that any one treatment option delivered completely in isolation will be ‘the best’ (Watson & Nussbaum, 2020). By way of an illustrative example, in a randomized controlled clinical trial (Kumaran and Watson 2018) we recruited patients with chronic OA knee. 45 patients were randomized into an active treatment group, placebo intervention group and a control group. The control group only received best current standard care (exercise and advice) which was common to all 3 groups. The CRET was delivered using an Indiba Activ device, with 8 sessions over a 4 week period with a 15 minute treatment time (5 minutes in CAP mode, 10 minutes in RES mode) at a comfortable thermal level. The active treatment group demonstrated significantly greater pain relief post treatment when compared with both the placebo and control groups, sustained at follow up – which was also reflected in their function scores. Importantly, benefits were not claimed for the treatment as a replacement for current best care but as adjunct to its use. The patient who is in receipt of best current care (lets say in this case, exercise, advice and education) will be significantly advantaged if Indiba based therapy is added to the treatment programme – not that Indiba replaces existing best care or that it out performs all existing therapy. If you were the patient with OA knee and it was known that the addition of Indiba to your treatment programme gave you a significant and long lasting advantage relating to pain and function, would you not wish for the therapist to deliver?? Other studies, including Coccetta et al (2019) report a very similar trial with equally strong clinical improvements.

Summary
Indiba is one manufacturers implementation of a radiofrequency (RF) device. It specifically uses a frequency of 448kHz for which there is extensive and robust evidence from in vitro (cell), lab based and clinical studies in human, small animal and equine domains. The fact that there is specific published evidence with Indiba devices puts it in a different league from most other CRET/TECAR devices.

It is not a panacea for “all ills” – but the range of applications for which there is evidence covers a wide range. The benefits are clinically significant and long lasting. It is at its optimum when used in conjunction with other therapeutic interventions – i.e. as a part of a package of care – and there is no doubt that when employed in this way, the patient (whether animal or human) will be significantly advantaged. The ongoing research will enable us to make more informed clinical decisions in the future, but that would be true for any modality. There is sufficient evidence and data to justify the clinical use of Indiba at the present time.

References
Al-Mandeel, M. and T. Watson (2020). Pulsed and Continuous Shortwave and Radiofrequency Therapies. Electro Physical Agents: Evidence-Based Practice. T. Watson and E. Nussbaum, Elsevier Health Sciences.
Beltrame, R., G. Ronconi, P. E. Ferrara, L. Salgovic, S. Vercelli, C. Solaro and G. Ferriero (2020).
“Capacitive and resistive electric transfer therapy in rehabilitation: a systematic review.” International Journal of Rehabilitation Research 43(4): 291-298.
Coccetta, C. A., P. Sale, P. E. Ferrara, A. Specchia, G. Maccauro, G. Ferriero and G. Ronconi (2019). “Effects of capacitive and resistive electric transfer therapy in patients with knee osteoarthritis: a randomized controlled trial.” Int J Rehabil Res 42(2): 106-111.
Kumaran, B., A. Herbland and T. Watson (2017). “Continuous-mode 448 kHz capacitive resistive monopolar radiofrequency induces greater deep blood flow changes compared to pulsed mode shortwave: a crossover study in healthy adults.” European Journal of Physiotherapy 19(3): 137-146.
Kumaran, B. and T. Watson (2015). “Radiofrequency-based treatment in therapy-related clinical practice – a narrative review. Part I: acute conditions.” Physical Therapy Reviews 20(4): 241-254.
Kumaran, B. and T. Watson (2016). “Radiofrequency-based treatment in therapy-related clinical practice – a narrative review. Part II: chronic conditions.” Physical Therapy Reviews 20(5-6): 325-343.
Kumaran, B. and T. Watson (2018). “Skin thermophysiological effects of 448 kHz capacitive resistive monopolar radiofrequency in healthy adults: A randomised crossover study and comparison with pulsed shortwave therapy.” Electromagn Biol Med 37(1): 1-12.
Kumaran, B. and T. Watson (2019). “Treatment using 448kHz capacitive resistive monopolar radiofrequency improves pain and function in patients with osteoarthritis of the knee joint: a randomised controlled trial.” Physiotherapy 105(1): 98-107.
Ribeiro, S., B. Henriques and R. Cardoso (2018). “The effectiveness of tecar therapy in musculoskeletal disorders.” Journal of Public Health and Health Systems 3(5): 77-83.
Watson, T., Ed. (2008). Electrotherapy : Evidence Based Practice. Edinburgh, Churchill Livingstone – Elsevier.
Watson, T. (2010). “Narrative Review : Key concepts with electrophysical agents.” Physical Therapy Reviews 15(4): 351-359.
Watson, T. (2024). “Shockwave and TECAR therapies: fad, fashion, hype or evidenced.” In Touch 186: 17-22.
Watson, T. and E. Nussbaum (2020). Electro Physical Agents: Evidence-Based Practice, Elsevier Health Sciences.