EFFECTIVENESS OF NON-INVASIVE SOMATOSENSORY PHYSICAL THERAPY INTERVENTIONS FOR THE MANAGEMENT OF COMPLEX REGIONAL PAIN SYNDROME (CRPS)

K. Joubran¹, P. Kitai², H. Ofek¹

¹Zefat Academic College, Physical Therapy, Zefat, Israel, ²Sha'ar Haguf Physical Therapy Clinic, Sha'ar HaGolan, Israel

Background: Complex Regional Pain Syndrome (CRPS) is considered a neuropathic condition that might develop post-injuries of the extremities. Somatosensory dysfunction symptoms have a significant part in the clinical characteristics and are part of the diagnosis for CRPS. Therefore, an optional treatment rationale would be treating through exposure to somatosensory input and treating through exposure to somatosensory input and sensory retraining.

Purpose: To review and summarize the effectiveness of non-invasive somatosensory treatments and modalities in reducing pain and other impairments coupled with CRPS and in improving function, and to make it accessible for clinicians.

Methods: We systematically reviewed the literature to identify clinical interventional trials regarding CRPS and somatosensory treatments, using PRISMA guidelines. The relevant studies were searched using the PubMed database, from inspection to July 30^th, 2022. Search terms that were used are Complex Regional Pain Syndrome, sensory treatment, sensory stimulation, sensory rehabilitation, tactile discrimination, tactile stimulation, non-invasive neurostimulation techniques, and transcutaneous electrical nerve stimulation. Results were reviewed by 2 reviewers and the final selection of articles was reached by consensus. The methodological quality was assessed using the PEDro checklist.

Results: Nineteen articles matched the inclusion criteria, with the methodological quality varying from poor to good. Non-invasive somatosensory interventions for CRPS can be divided into two main groups: 1. Transcutaneous Electrical Nerve Stimulation (TENS) and 2. sensory/ sensory-motor training.
Out of 11 studies that used the TENS modality, 8 used low frequency, while one used high frequency, one compared between the effect of low versus high frequencies and one study did not report details about the treatment protocol. Ten studies exhibited reduction in pain following TENS treatment, however, one study revealed an advantage of ultrasound therapy and whirlpool bath over the TENS coupled with whirlpool bath.
In relation to function and impairments, TENS can improve function, range of motion, strength, quality of life, and weight acceptance. Furthermore, it can reduce edema, hyperalgesia, and analgetic gait.
Concerning the sensory training group, pain reduction was exhibited in seven out of eight interventions, including sensory-motor training, sensory discrimination training, or stimulation, and using explicit, active sensory learning approaches. Five studies within this group exhibited improvement in function; five in two-point discrimination; and two studies reported a reduction in anxiety and depression.

Conclusions: There are variate non-invasive somatosensory-based interventions that can be offered for the management of CRPS. However, their effectiveness should be further studied in larger, methodologically more rigorous randomized studies.

Implications: The results of this review and the protocols included will be summarised and made accessible for clinicians as an evidenced-based source of CRPS management. Acquaintance with evidence-based specific treatment protocols for the relief of symptoms and the improvement of function in individuals with CRPS will enlarge the toolbox for physical therapy treatments in this population.

Funding acknowledgements: We have no funding to declare.

Keywords:
Complex regional pain syndrome
Sensory training
Transcutaneous electrical nerve stimulation

Topics:
Pain & pain management
Disability & rehabilitation

Did this work require ethics approval? No

Reason: We conducted a systematic review.