Treatment of the Carpal Tunnel Syndrome with Laser

Luiz Antonio de Lima Resende; Tamiris Aparecida Monteiro; Gustavo José Luvizutto; Marcelo Fernando Zeugner Bertotti; Thiago Dias Fernandes; José Eduardo Corrente; Trajano Sardenberg

doi:10.17140/noj-2-112

Luiz Antonio de Lima Resende, Tamiris Aparecida Monteiro, Gustavo José Luvizutto, Marcelo Fernando Zeugner Bertotti, Thiago Dias Fernandes, José Eduardo Corrente, Trajano Sardenberg

Abstract

Objecive : To test the effectiveness of low intensity laser therapy in patients with carpal tunnel syndrome (CTS). Methods : Patients with clinical and ENMG diagnosis of CTS never previously treated were included and submitted to clinical evaluation and conduction studies before and after treatment. Sensory and motor conduction studies were performed by conventional described techniques. Low intensity laser treatment was by 660 nm wave length, average power of 30 nw, continuous operation area of 0.06 cm2 , fluence of irradiation of 10 J/cm2 , exposure of 10 seconds per point, totalling 6 points of irradiation on the carpal tunnel, from the proximal to the distal sense. Laser was positioned at 90° to the skin, 2 sessions per week during 3 months were performed (24 sessions). To this moment 30 hands of 18 patients were studied. Results : Clinical data and different parameters on the conduction studies of the median nerve showed improvement after the treatment. Conclusion : In our opinion low intensity laser therapy is a new, not expensive and easy to apply encouraging treatment for CTS.

Keywords: Carpal tunnel syndrome; Laser; Treatment; Carpal tunnel syndrome; Laser; Treatment

Introduction

The Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy. Af- 1-10 ter surgery different types of complication may occur,1-10 then search for new clinical forms of treatment is necessary. The main clinical treatments are physical therapy, bracing, steroid 11-13 injections and alternative therapies as yoga and acupuncture. In recent years, it has taken on increasing importance treatments with ultrasound and laser.14

The effects of laser on the peripheral nervous system are controversial. Laser application on the distal sensory branch of the radial nerve led to increased latency and decrease velocity.15 Application on the median nerve in 51 normal volunteers, led to a slight increased latency in sensory antidromic conducting study. Such data were not confirmed by others,

was not confirmed by others. In one meta-analysis, only 2 papers with clinical and conduction studies improvement were found. One Brazilian study proposed a randomized controlled trial,

Methods

After approval by the Ethics Committee on Human Research of our Institution, patients with clinical and ENMG diagnosis of CTS never previously treated were included. Exclusion criteria were diabetes and other endocrine diseases, renal failure, alcoholism or occupational exposure to environmental toxic agents, patients with any other medical conditions that cause polyneuropathy, and antecedents of previous surgery, trauma, burns or fractures in the affected limb. Visual Analogic Scale (VAS), Carpal Flexion Amplitude (CFA) using a goniometer and Strength of the Abductor Pollicis Brevis (SAPB) muscle using a dynamometer (Daniels) were determined before and after treatment. Antidromic sensory conduction studies using ring electrodes, and motor conduction studies using standard surface disc electrodes were performed by conventional described techniques22 – Figure 1. Low intensity laser treatment using galliumindium-phosphorus-aluminium Laser emitter was by 660 nm wave length, average power of 30 nw, continuous operation area 2 2 of 0.06 cm2, fluency of irradiation of 10 J/cm2, exposure of 10 seconds per point, totalling 6 points of irradiation on the carpal tunnel, from the proximal to the distal sense. Laser was positioned at 90° to the skin, 2 sessions per week during 3 months were performed (24 sessions) – Figure 2. Statistical analysis from the data obtained before and after treatment was done by the paired “t” test. Correlation between clinical and conduction studies was performed by the Spearman correlation test and Pearson correlation test.

Results

To this moment 30 hands from 18 patients were analysed (6 with unilateral CTS; 12 with bilateral CTS). From the clinical study, VAS, CFA and SAPB showed improvement after treatment (p<0.001, p<0.0028 and p<0.0001, respectively). VAS values are showed in the Graphic 1. From the conduction studies, distal motor latency and sensory conduction velocity improved after treatment (p<0.0003 and 0.0002, respectively). Distal motor latency values are showed in the Graphic 2. For the amplitude no significance was observed. In the Spearman correlation test, no statistic significance was observed. In the Pearson correlation test negative correlation between distal motor latency and SAPB was found (for larger values of latency minor values of strength). It was also observed positive correlation between distal motor latency and VAS (for larger values of latency larger values on the visual analogic scale of pain).

Discussion

The analysis of the 30 hands from 18 patients was possible in the last 2 years. For these 30 hands, visual analogic scale, carpal flexion amplitude, strength of the APB muscle, distal motor latency and sensory conduction velocity showed improvement. One study found no statistically significant clinical differences between the group of patients treated with laser and the placebo group, but improved sensory conduction in patients who received Laser was observed, similarly to our data. The Spearman correlation test between clinical data and conduction studies parameters showed no statistic significance. As the Spearman correlation test applies predominantly to ordinal scale variables, and, as in our study the only ordinal scale used was the VAS (visual analogue scale of pain, ranging from zero to ten), we opted for conducting also the Pearson correlation test. The results by this test were logical and predictable, for larger values of distal motor latency, minor values of the strength of the APB muscle and larger values of the VAS were found.

In the last years some encouraging results of Laser for 24,25 the CTS were described, as subjective improvement; or im- 26,27 provement of the conduction studies and clinical data. In a recent prospective, randomized, placebo-controlled trial Evcik, et al. reported positive effects on hand and pinch grip strengths after low-level laser therapy.28 Beneficial effects of the combination of laser therapy with other methods as night orthopedic 25 29 splint25 or magnetic stimulation29 were also reported.

Conclusion

In our opinion, low intensity laser therapy is emergent as a new, not expensive and easy to apply encouraging treatment for CTS.

Neuro

N Mean Std Dev Std Err Minimum Maximum

Mean 95% CL Mean Std Dev 95% CL StdDev

DF t Value Pr > |t|

19 5.27 <.0001 Graphic 1: Paired “t” test for the visual analogic scale (before and after treatment).

N Mean Std Dev Std Err Minimum Maximum

Mean 95% CL Mean Std Dev 95% CL StdDev

DF t Value Pr > |t|

Graphic 2: Paired “t” test for the distal motor latency (before and after treatment).

Conflict Of Interest

Aknowledgments

We are grateful to the FAPESP, for the financial support (Process number 2013/10.082-4).

Consent Statement

The authors have obtained written informed consent from the patient before submission of this manuscript for publication.

Treatment of the Carpal Tunnel Syndrome with Laser

Abstract

Introduction

Methods

Results

Discussion

Conclusion

Neuro

N Mean Std Dev Std Err Minimum Maximum

Mean 95% CL Mean Std Dev 95% CL StdDev

DF t Value Pr > |t|

N Mean Std Dev Std Err Minimum Maximum

Mean 95% CL Mean Std Dev 95% CL StdDev

DF t Value Pr > |t|

Conflict Of Interest

Aknowledgments

Consent Statement

References