Correlation between foot progression angle and pelvic tilt in individuals with pesplanus-A cross-sectional study

Pes planus or Flat foot refers to the loss of Medial Longitudinal Arch of the foot. Dysfunction of Arch complex can alter the biomechanics of lower limb and lumbar spine causing increased risk of injury. This condition can influence gait mechanics, postural stability and overall musculoskeletal alignment. About 20 to 37 percentage of the population is estimated to have pes planus and a majority of them are flexible pesplanus.The navicular drop test  which has excellent reliability both intrarater and interrater, with ICC values ranging from 0.914 to 0.945 will be used to assess flatfoot in individuals. The Navicular drop test will be performed by palpating navicular tuberosity at the medial side of the foot and marking it with the marker. The height of the navicular tuberosity from the ground will be measured with the subjects sitting on a chair with their knees flexed to 90 degrees while maintaining a neutral foot position that is non weight loading posture by marking it on the paper. The subjects then will have to stand up with their feet shoulder width apart that is weight loading posture and mark the navicular tuberosity position in the paper, the vertical distance between the ground and navicular tuberosity will be measured. Using a ruler, we should find the difference and if it is greater than 10 mm which denotes flexible flatfoot. The navicular drop test will be performed on both the sides Right Side and Left Side. The Navicular drop test will be assessed with mean average of 3 times. One of the key biomechanical parameters affected in individuals with Pes planus is Foot Progression Angle. The Foot Progression Angle is  the angle made by the long axis of the foot from the heel to 2nd metatarsal and the line of progression of gait. Foot Progression Angle is  the degree of in toeing or out toeing that is identified during gait assessment. FPA will be assessed using  foot plantar pressure analysis. To assess foot plantar pressure analysis, the participants has to stand barefoot. The test is performed with eyes open. The subjects follow 3 steps to perform dynamic test which provides Foot progression angle. 1. Subject is asked to step on the mat with both legs placed at wide base of support. 2. Two steps are placed forward to move out from the mat and followed by four steps forward by placing only one leg on the mat and the other outside. 3. The subjects are encouraged to walk normally until proper steps on OHM 3000 are recorded. The Foot progression are recorded in the plantar pressure analysis equipment. Interpretation for foot progression will be for in toeing less than 0 degree, for normal 0 to 20 degree, for out toeing greater than 20 degrees and it will be assessed with mean average of 3 times. Pelvic tilt, defined as the orientation of the pelvis in the sagittal plane, is a critical factor in maintaining postural alignment and efficient locomotion. Pelvic tilt is often quantified using the angle between the horizontal and a line connecting the anterior superior iliac spine  and the posterior superior iliac spine . Pelvic tilt will be assessed using pelvic inclinometer. The subjects are instructed to stand barefoot and loosen their pant for palpating Anterior Superior Iliac Spine and Posterior Superior Iliac Spine. The subjects are instructed to fold their hands at their chest level. Palpating Anterior Superior Iliac Spine and Posterior Superior Iliac Spine. Marking it with the pen. Using Pelvic inclinometer, placing one calliper on Anterior Superior Iliac Spine and the other on Posterior Superior Iliac Spine. Making sure not to move the callipers while reading the measurements. Assessed with mean average of 3 times on both the sides. Interpretation for pelvic tilt while normal values for Male is 9 degrees, normal values for female is 12 degrees. The study will be conducted after obtaining approval from the Clinical trials registry India at the SDUAHER, Kolar. Explanation of the study will be given to the participants. Informed consent will be taken from participants before the commencement of the study. Volunteers will be screened for eligibility based on the inclusion criteria and Navicular drop test will be used to assess flatfoot in individuals. Demographic data such as age, gender, height, weight and BMI will be collected from participants. Sample size calculation will be done using G power analysis software version 3.1. Sample size estimation calculated is 84 based on 95 percentage, significance level with 5 percentage margin of error, 80 percentage power and adjusting the sample with 20 percentage based on feasibility and missing data so the total sample size will be 100. Sample Size  n is equal to 100, Confidence Level Z is equal to 95 percentage Z is equal to 1.96, alpha 0.05, power of the study is 80 percentage or 0.8, Margin of Error E is equal to 5 percentage 0.05. For analysis and statistical Methods, descriptive statistics and inferential statistics will be done. Mean and standard deviation will be used to represent numerical variable. Frequencies will be used to represent categorical variable. Parametric, non parametric and correlation analysis will be done after checking the normality of the data. SPSS version 25 will be used for analysis. Studies suggest that Flat arched feet have been associated with altered foot function, prolonged calcaneal eversion, increased tibial internal rotation, and increased forefoot abduction. While pes planus is known to alter lower extremity biomechanics, leading to compensatory mechanisms that may affect pelvic alignment, the specific nature and extent of the correlation between Foot Progression Angle and pelvic tilt remain unclear. Most of the studies have shown the relationship between foot posture and pelvic tilt. There is lack of research on Correlation between foot progression angle and pelvic tilt in flat foot. Understanding this correlation is crucial for developing targeted interventions to improve gait mechanics and postural stability in affected individuals.