Effects of transcutaneous electrical nerve stimulation (TENS) on acute postoperative pain intensity and mobility after hip fracture: A double-blinded, randomized trial

Abstract

Background

Transcutaneous electrical nerve stimulation (TENS) is a noninvasive modality which may be used to reduce acute postoperative pain. Intense perioperative pain within the first few days after hip fracture surgery is common and is related to negative consequences such as restricted and delayed ambulation.

Objective

The objective of the present study was to examine the effect of incorporating TENS treatment on pain intensity, and mobility, with standard rehabilitation care during the acute post-operative phase following Gamma-nail surgical fixation of extracapsular hip fractures.

Materials and methods

Forty-one patients were randomly assigned to a supplement of 30 mins of active TENS or sham TENS. The standard rehabilitation care included five daily 30 mins physical therapy treatments beginning 24 hrs after surgery. Outcome measures were: pain intensity at rest, at night and during ambulation (assessed with the Numeric Rating Scale; Functional Ambulation Classification instrument; time to complete five sit-to-stand tests; and two-minute walk test). Data were analyzed with Wilcoxon score rank tests. Significance was set at p≤0.05.

Results

Significantly greater pain reduction during walking was noted in the active TENS group compared to sham TENS group (differences between the fifth and the second days: 2.55±1.37 vs 1.06± 1.11, respectively; p=0.0011). Additionally, advantage of active TENS was demonstrated in greater increase in walking distance on the fifth day and higher level of mobility compared to the sham TENS group. No additional effects of active TENS were noted on pain intensity at rest and at night and on five times sit-to-stand performance.

Conclusion

Addition of TENS to the standard care of elderly patients in the early days following Gamma nail surgical fixation of extracapsular hip fracture is recommended for pain management while walking and functional gait recovery. The effect of TENS on long-term functional outcomes should be explored in future studies.

Trial registration

The trial was registered at the ISRCTN registry: ID ISRCTN32476360.

Keywords:

• transcutaneous electrical nerve stimulation
• TENS
• pain
• hip fracture
• acute postoperative
• mobility

Acknowledgments

We thank the physical therapy staff and the medical staff of the Department of Orthopedics B, Galilee Medical Center for their full cooperation and support during the execution of the study. We thank Mr. Adeeb Doha and Mrs. Mor Kliger Tendler, two physical therapists, for their help in data collection. We also thank all our patients who were willing to participate in this placebo-controlled blinded study.

Abbreviations

TENS, transcutaneous electrical nerve stimulation; DHS, dynamic hip screw; FAC, functional ambulation classification; NRS, numeric rating scale; 5XSTS, five times sit to stand test; 2MWT, two minute walk test; SD, standard deviation.

Ethics Approval

The study was approved by the Helsinki Committee of the Galilee Medical Center (number 0110-14-NHR).

Availability Of Data And Materials

The dataset used and analyzed during the current study is available from the corresponding author on reasonable request.

Author Contributions

All authors contributed towards study conception and design, interpretation and collection of data, drafting and critically revising the paper, gave final approval of the version to be published and agreed to be accountable for all aspects of the work. In addition, SAN was the study coordinator, HS provided the weight-bearing instructions and was responsible for final decision regarding eligibility and MEG was responsible for data analysis and the preliminary writing of the manuscript.

Disclosure

The authors report no conflicts of interest in this work.