Effect of Foot-ankle Exercise Using Elastic Band on Diabetic Foot Ulcer Incidence in Patient With Diabetes Neuropathy
Phase: NA
Conditions: Diabetic Foot Ulcer (DFU), Neuropathy (Disorder)
Sponsor: St Elisabeth School Health Science

  
 
PROTOCOL STUDY AND STATISTICAL ANALYSIS PLAN 
  
 
 
 
 
 
 
Effect of foot-ankle exercise using an elastic 
band on diabetic foot ulcer incidence in 
patients with diabetic neuropathy 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
               1 May 2025

Design 
  
The study used a randomized controlled trial (RCT) with blinding.  
 
 
Outcomes 
 
Primary Outcome Measure:  
Diabetic foot ulcer (DFU) incidence DFU, defined as a wound in the area below the ankle that 
reaches at least the epidermis and part of the dermis, as diagnosed by an internist. Time frame 1 
year. 
 
Secondary Outcome Measure:  
1. Diabetic neuropathy examination score The accumulation score of the result measurement 
consists of eight items, two testing muscle strength, one a tendon reflex, and five testing 
sensation. The min-max score is 0-16. The higher the score indicates the more severe the 
neuropathy. The score was determined by doing a physical examination. Time Frame: 0, 12 
weeks, and a year. 
2. Control glycemic HbA1c levels, which are the level of blood sugar control over a period of 
time. 3 months, measured by analyzing blood serum in a laboratory using the National 
Glycohemoglobin Standardization Program (NGSP). Time Frame: 0, 12 weeks, and a year 
\ 
3. Brain-derived neurotrophic factor BDNF levels, which are defined as biomolecular markers 
that can indicate the severity of diabetic neuropathy, as measured by analyzing blood serum 
using the ELISA technique Time Frame: 0, 12 weeks, and a year   
4. Walking speed Walking speed is the ratio between times measured while walking in second 
as fast as possible on a flat and straight trajectory at a certain distance. The track distance 
used in the study was 5 meter. The time of waking was measured using a stopwatch. Time 
Frame: 0, 12 weeks, and a year  
5. Foot ankle range of motion ankle range of motion, which is the degree of joint movement 
in the feet during flexion, extension, inversion, and eversion, as measured using digital 
goniometry. Time Frame: 0, 12 weeks, and a year  
6. Callus incidence: Callus is the thickness of the plantar skin area that can be determined by 
inspection. Time Frame: 0, 12 weeks, and a year 
7. Neuropathy symptom score. The accumulation score of the result measurement consists of 
sixteen item about the symptoms of neuropathy. The min-max score is 0-16. The higher 
score indicates the more severe of neuropathy. The score was determined by interviewing 
the patient. Time Frame: 0, 12 weeks, and a year. 
 
 
Population and Sample 
 
The population in this study consisted of patients with diabetic neuropathy residing at the first 
health facility in Central Java, Indonesia. The sample consisted of approximately 80 participants, 
divided into an intervention group (n = 40) and a control group (n = 40). Randomization was 
conducted using block randomization.    
The inclusion criteria were 
• 
having type 2 diabetes  
• 
can walk a minimum 10 meters 
• 
having diabetic neuropathy 
The exclusion criteria were 

• 
having a stroke 
• 
having an active ulcer 
• 
having fractures on the foot 
• 
Having a diabetic ulcer history 
 
 
Instrument 
 
We used an elastic band with 0.5 and 0.65 thickness to give the foot-ankle exercise. Diabetic 
neuropathy symptoms were measured using the neuropathy symptom score questionnaire.  The 
diabetic neuropathy sign was measured using the diabetic neuropathy examination score 
questionnaire. We also used a turning fork at 128 Hz, a monofilament 10g, a hammer to measure 
the diabetic neuropathy examination score. Digital goniometry was used to measure the foot-
ankle range of motion. A stopwatch was used to measure the walking speed. 
 
 
Intervention 
  
The intervention and control groups will receive usual care, which includes pharmacological 
treatment and self-care guidelines. The intervention group will receive ankle-foot exercises using 
elastic bands for one year. The ankle-foot exercises focus on the ankle, metatarsophalangeal, and 
interphalangeal joints. In accordance with exercise guidelines for preventing DFU, the exercises 
will be supervised by a trained healthcare professional for 12 weeks, and will be continued with 
the aid of a video protocol for ankle-foot exercises using elastic bands for 9 months. The exercise 
was done 3 times a week (15x/until they tired x 2 sets). The exercise used an elastic band with 
different thicknesses (0,5 mm in 12 weeks and 0,65 mm in nine months).  Compliance with the 
foot exercises will be monitored by researchers through a logbook. Researchers will visit 
participants every three months to monitor the implementation of the exercises. Both the control 
and intervention groups will receive standard care for diabetes patients from the community 
health center. 
 
 
 
Data Collection 
 
Data will be collected at baseline, 12 weeks, and one year after the intervention by researchers 
not involved in the randomization process to ensure blinding.  
 
 
Statistical analysis plan 
 
Data will be analyzed using SPSS. Intention-to-treat analysis will be conducted in this study 
with blinded analysis (blinded data analyst). Baseline characteristics include individual 
characteristics such as age and gender, as well as factors related to diabetes that may be 
associated with DFU, such as duration of diabetes, duration of signs and symptoms related to 
neuropathy,  HbA1c levels,  BDNF  levels,  walking speed,  range of motion (ROM),  vibration 
sensitivity, ABI, degree of neuropathy, and hypertension. The baseline characteristics 
homogeneity of both groups will be assessed using chi-square, independent t-test, or Mann-
Whitney U test. Repeated ANOVA or Friedman and post hoc will be used to analyze the 
difference in the outcomes before and after intervention in both groups. Significant 
difference will be considered with ά=5%, but for he description of the effect of the intervention, 
the effect size (Cohen coefficient) and the difference between the means will be calculated with 
their respective 95% confidence intervals.