
Understanding the role of stimulation in reflexology: development and testing of a robotic device.
Flynn, Louis & Bush, Tamara & Sikorskii, A & Mukherjee, Ranjan & Wyatt, G.
European Journal of Cancer Care · 20 . 686-96, September 2011
reflexology, breast cancer, symptom management, robotic device,
Reflexology is a common choice of women with breast cancer as supportive care during treatment. It involves stimulation of specific locations of the feet called reflexes using a specialised walking motion with the thumb of the reflexologist.
Reflexology has shown potential for the successful management of cancer and treatment related symptoms and improvement in physical functioning; however, to date, the mechanism of action for these improvements is unknown.
One confounder to the study of reflexology is the ‘human factor’. To study the effects of the stimulation of the reflexes independent of the ‘human factor’, there is a need for an alternative method for the delivery of reflexology.
The purpose of this work was to begin to uncover the specific components of reflexology which may or may not play a role in symptom management and improvements in physical functioning among cancer patients. Testing against hands-on reflexology is planned in the future, as the device may provide an alternative for some cancer patients who are homebound. The intent of this line of work is not to replace a therapist, but rather to advance the science by isolating the key active ingredients of reflexology, and in the long run possibly offer in-home or in-clinic options for some patients.
While multiple studies have investigated the effect of reflexology on HRQOL of cancer patients, there is no single scientifically established mechanism of action for how reflexology affects HRQOL outcomes including symptoms and function. One theory suggests that the mechanism of action is that the nerve endings in the feet connect with different areas of the body, and the direct pressure on a specific nerve ending of the foot stimulates the corresponding area of the body for symptomatic relief (Hodgson 2000). According to this theory, specific areas of the foot (reflexes) correspond to specific organs or systems of the body (Fig. 1), and thus manipulation of these specific areas can lead to the improvement in symptoms. A protocol that targets reflexes tied to symptoms of breast cancer and its treatment has been developed (Wyatt et al.2005).
In addition to the stimulation of specific reflexes, the ‘human factor’ is also thought to influence outcomes of reflexology. The human factor includes the experience of the reflexologist in finding and stimulating specific reflexes. The interpersonal style of the reflexologist during the session may also be a confounding human factor. In addition, the human touch by itself may have a therapeutic effect, and the touch produced by different reflexologists may be different (e.g. different motion patterns or methods of force application). This variability in the delivery of reflexology that is due to human factor may explain some of the variable effects on patient outcomes.
Thus, to understand the role of stimulation of the reflexes in reflexology, removing the human factor is necessary. One of the ways to remove the human factor is to stimulate the reflexes using a mechanical device.


This research involves two distinct samples:
- Sample 1: breast cancer survivors (n = 13);
- Sample 2: women undergoing chemotherapy for breast cancer (n = 13).
Reflexology protocol
According to a breast cancer-specific reflexology protocol tested in the ongoing RCTs of hands-on reflexology (Wyatt et al. 2005), the reflexes associated with symptoms of breast cancer and its treatment are located in three regions: (1) the sole of the foot; (2) around the base of the ankle on the top of the foot; and (3) at the base of the toes on the top of the foot. During stimulation, the mechanical device mimics the thumb-crawling motion of a reflexologist. The total time for the protocol is 15 min per foot.
Stimulation of the sole of the foot
Seven reflexes are stimulated as discussed below.
- Spine reflex
- Lung and diaphragm reflexes
- Kidneys and adrenal reflexes
- Spleen reflex
- Intestinal reflex
Stimulation on top of foot
- Breast and chest reflexes
Stimulation of the base of the ankle
- Lymphatic reflexes
(For more details see the full text)
Goal 2
In sample 1, the summary of acceptability ratings in Table 2 revealed very high mean levels for: session duration (4.77), pleasantness (4.69), relaxation (4.77), absence of pain during session (4.46), comfort of leg and foot (4.69), comfort of chair height (4.85) and acceptability of socks worn (5.00). Women were also asked to rate the acceptability of three device sizes for home use. Medium and small sizes received the highest ratings and the current size was rated at the mean of 3.08 (neutral). Furthermore, in sample 1, women were breast cancer survivors who were no longer on treatment and therefore had few symptoms as reflected by the mean symptom severity score of 0.96 (Table 3). The symptom severity and interference and physical function did not change (improved insignificantly) from pre- to post-device sessions, further supporting feasibility and acceptability of the robotic reflexology device.

Goal 3
In sample 2, the symptom severity significantly decreased (P = 0.02) from pre- to post-device sessions, and physical function improved (P = 0.06) from pre- to post-device sessions. The effect sizes for these improvements expressed as Cohen’s d (difference between means in standard deviation units) were 0.86 for symptom severity and 0.70 for physical function. In Cohen’s classification (Cohen 1988), the cut-off for the large effect size is 0.80, and our results point to the potential efficacy of the device with respect to symptom management and improvement of physical function during chemotherapy.
Furthermore, in sample 2, three women dropped out after the intake interview, and did not complete the device sessions and post-sessions interview. The other 10 women out of 13 in sample 2 (77%) completed both interviews. Of these 10 women, nine completed all four device sessions, and one woman completed three out four. Thus, feasibility of device sessions held in the clinic was supported.
Goals 2 and 3
Data from preliminary testing indicate that the application of reflexology through a robotic device was not only acceptable to laboratory patients but showed beneficial trends in decreasing symptom severity and increasing physical function among clinic patients receiving chemotherapy.
The reduction in symptom severity from pre- to post-device sessions was statistically significant (P = 0.02, Table 3). Thus, it is possible that the stimulation of the reflexes alone could be beneficial as supportive care for cancer patients undergoing treatment; however, the efficacy conclusions cannot be drawn from the present study.
The results obtained in our pilot sample of women undergoing treatment could be used to appropriately power a larger study, which would control for extraneous influences via randomisation, and compare device-delivered reflexology to hands-on reflexology and standard care for symptom management.
