This study aims to evaluate the effects of four-cell galvanic bath therapy on pain and balance in patients with diabetic distal symmetric polyneuropathy. Diabetic peripheral neuropathy is a common complication of diabetes that can lead to pain, sensory loss, and impaired balance. In this randomized controlled study, participants received either conventional rehabilitation alone or conventional rehabilitation combined with four-cell galvanic bath therapy. The intervention was applied over a 4-week period. Pain and balance outcomes were assessed using standardized clinical measures. The findings of this study may help determine the effectiveness of galvanic bath therapy as a supportive treatment option in patients with diabetic neuropathy.

Diabetic distal symmetric polyneuropathy (DSPN) is one of the most prevalent chronic complications of diabetes mellitus and is characterized by progressive peripheral nerve damage, leading to symptoms such as distal sensory loss, neuropathic pain, and impaired proprioception. These alterations negatively affect postural control mechanisms, resulting in balance impairment, increased risk of falls, and reduced functional independence. As a consequence, DSPN significantly decreases quality of life and poses an important clinical and socioeconomic burden.

Conventional rehabilitation programs, including range of motion, strengthening, balance, coordination, and endurance exercises, are commonly used in the management of DSPN. However, despite these interventions, persistent neuropathic pain and balance deficits often remain inadequately controlled. Therefore, there is a growing interest in adjunctive therapeutic approaches that target both sensory and motor components of postural control.

Electrical stimulation modalities have been proposed as potential therapeutic options due to their ability to modulate peripheral nerve excitability and enhance somatosensory feedback. Four-cell galvanic bath therapy is a non-invasive intervention that applies low-intensity direct current through water-filled electrodes to the upper and lower extremities. This method may stimulate cutaneous receptors and peripheral nerve endings, increase afferent sensory input, and facilitate neuromuscular activation. Through these mechanisms, galvanic bath therapy may contribute to improved postural stability and reduction of neuropathic pain. However, current evidence regarding its combined effects on both pain and balance in patients with DSPN is limited, highlighting the need for well-designed clinical trials.

This study was designed as a prospective, randomized, controlled, single-blind clinical trial including patients aged 40-75 years diagnosed with DSPN. Participants were randomly assigned in a 1:1 ratio to either an intervention group receiving four-cell galvanic bath therapy in addition to conventional rehabilitation or a control group receiving only conventional rehabilitation. The rehabilitation program consisted of standardized exercises including range of motion, stretching, strengthening, balance, coordination, and endurance training, and was applied for 4 weeks, three sessions per week, with each session lasting approximately one hour.

In the intervention group, four-cell galvanic bath therapy was administered concurrently with the conventional rehabilitation program. The application was performed using a standardized protocol to ensure consistency across participants. Outcome measures were assessed at baseline and after the intervention period using validated clinical assessment tools. Pain intensity and balance performance were evaluated as primary outcomes, while additional functional and quality of life parameters were assessed as secondary outcomes.

The primary objective of this study is to investigate the effectiveness of four-cell galvanic bath therapy on reducing pain and improving balance in patients with DSPN. A secondary objective is to explore whether enhanced somatosensory input through electrical stimulation contributes to improved postural control and functional outcomes. The findings of this study are expected to provide clinically relevant evidence regarding the role of galvanic bath therapy as an adjunctive treatment modality in the rehabilitation of patients with diabetic peripheral neuropathy.

Inclusion Criteria:

1. Diagnosis of type 2 diabetes mellitus
2. Confirmed diagnosis of diabetic distal symmetric polyneuropathy according to the 2009 Toronto Consensus criteria
3. Age between 40 and 75 years
4. Adequate cognitive function to understand and respond to questionnaires and follow instructions (Mini-Mental State Examination score ≥ 24)
5. No initiation or dosage change in neuropathic pain medication within the last 1 month
6. Sufficient functional mobility to participate in the assessment and treatment protocol (ability to stand independently or with minimal assistance)

Exclusion Criteria:

1. Presence of lower extremity amputation
2. Active diabetic foot ulcer, significant skin integrity impairment, or open wound in the treatment area
3. Cognitive impairment (MMSE < 24) or communication problems interfering with assessments
4. Presence of orthopedic, musculoskeletal, or peripheral conditions affecting balance
5. Medical instability
6. Use of medications affecting balance or cognitive function
7. Use of assistive devices
8. Severe musculoskeletal disorders
9. Initiation or dosage change of neuropathic pain medication within the last 1 month
10. Presence of Charcot neuroarthropathy
11. Polyneuropathy due to causes other than diabetes

Individual participant data (IPD) will not be shared due to privacy concerns and institutional data protection policies.

The outcome assessor was blinded to group allocation to minimize assessment bias. Participants and care providers were not blinded due to the nature of the intervention.