Re-evaluating Electrotherapy in Shoulder Rehabilitation
Subacromial impingement syndrome (SAIS) is one of the most frequent causes of shoulder pain encountered by physiotherapists in daily clinical practice. In the quest to alleviate pain and restore function, clinicians often employ a multimodal approach. Alongside exercise, cryotherapy, and non-steroidal anti-inflammatory drugs (NSAIDs), interferential current (IFC) therapy has historically been a popular electrotherapeutic adjunct. However, the true efficacy of passive modalities is increasingly being scrutinized under the lens of evidence-based practice. A pivotal randomized, double-blind, sham-controlled study sought to determine if IFC actually provides any additional clinical benefit for patients suffering from SAIS.
The Study Design: Active vs. Sham IFC
To investigate the clinical effectiveness of IFC, researchers conducted a rigorous study involving 65 patients aged between 25 and 65 years. Each participant was formally diagnosed with SAIS through rigorous clinical evaluation and subacromial injection testing. The patients were randomly allocated into two groups: an active IFC group (33 patients) and a sham IFC group (32 patients). The foundational treatment was standardized across both groups; every patient received a prescribed exercise regimen, cryotherapy, and an NSAID protocol. Over a two-week period, the active group received ten 20-minute sessions of bipolar IFC therapy, administered five days per week. The sham group received identical parameters, minus the active current. Blinded researchers evaluated the patients using the Visual Analog Scale (VAS), Constant scores, and the Shoulder Disability Questionnaire (SDQ) at baseline, immediately following the intervention period, and at a one-month follow-up.
Outcomes: Assessing the Value of Passive Modalities
The results of the trial are highly informative for practicing physiotherapists. Out of the initial 65 participants, 60 successfully completed the study. Both the active IFC group and the sham IFC group demonstrated statistically significant improvements across all outcome parameters immediately post-treatment and at the one-month mark. However, the critical finding was the comparison between the two groups: there was absolutely no statistical difference in pain reduction or functional improvement between the active IFC group and the sham IFC group. Both groups improved equally, highlighting that the active interventions—exercise, localized cryotherapy, and pharmacological management—were the true drivers of clinical success.
Clinical Implications for Physiotherapists
For orthopaedic and musculoskeletal physiotherapists, these findings are a vital reminder to prioritize high-value care. The data explicitly demonstrates that adding IFC therapy to a standard rehabilitation program does not yield any additional benefit for SAIS. By phasing out ineffective passive modalities, clinicians can free up valuable session time to focus on what truly matters: targeted therapeutic exercise, manual therapy, load management, and patient education. Embracing this evidence not only optimizes patient outcomes but also streamlines clinic resources and reduces unnecessary healthcare costs.
References
Nazligul, T., Akpinar, P., Aktas, I., Unlu Ozkan, F., & Cagliyan Hartevioglu, H. (2018). The effect of interferential current therapy on patients with subacromial impingement syndrome: a randomized, double-blind, sham-controlled study. European journal of physical and rehabilitation medicine, 54(3), 351-357.
