Treatment of localized post-traumatic neuropathic pain in scars with 5% lidocaine medicated plaster

Abstract

Objective

To evaluate the use of 5% lidocaine medicated plaster (LMP) for treating painful scars resulting from burns or skin degloving.

Patients and methods

This was a prospective, observational case series study in individuals with painful scars <70 cm² in area, caused by burns or skin degloving. The study included a structured questionnaire incorporating demographic variables, pain evaluation using the numeric rating scale (NRS), the DN4 questionnaire, and measurement of the painful surface area. Patients with open wounds in the painful skin or with severe psychiatric disease were excluded.

Results

Twenty-one men and eight women were studied, aged (mean + standard deviation) 41.4 ± 11.0 years, with painful scars located in the upper extremity (n = 9), lower extremity (n = 19), or trunk (n = 1). Eleven patients (37.9%) had an associated peripheral nerve lesion. The scars were caused by burns (n = 13), degloving (n = 7), and/or orthopedic surgery (n = 9). The duration of pain before starting treatment with lidocaine plaster was 9.7 ± 10.0 (median 6) months. The initial NRS was 6.66 ± 1.84 points, average painful area 23.0 ± 18.6 (median 15) cm², and DN4 score 4.7 ± 2.3 points. The duration of treatment with LMP was 13.9 ± 10.2 (median 11) weeks. After treatment, the NRS was reduced by 58.2% ± 27.8% to 2.72 ± 1.65. The average painful area was reduced by 72.4% ± 24.7% to 6.5 ± 8.6 (median 5) cm². Nineteen patients (69%) showed functional improvement following treatment.

Conclusion

LMP was useful for treating painful scars with a neuropathic component, producing meaningful reductions in the intensity of pain and painful surface area. This is the first time that a decrease in the painful area has been demonstrated in neuropathic pain using topical therapy, and may reflect the disease-modifying potential of LMP.

Keywords:

• chronic postsurgical pain
• chronic post-traumatic pain
• lidocaine medicated plaster
• neuropathic pain

Acknowledgments

We thank our superiors and colleagues in the Hospital del Trabajador de Santiago Rehabilitation Department for their assistance with this study, and Derrick Garwood Ltd, Cambridge, UK, for editorial support, which was sponsored by Grünenthal GmbH, Germany.

Disclosure

The authors report no conflict of interest in this work.