This observational study aims to investigate the spinopelvic relationship parameters change during the five main positions during Muslim prayers. The main questions the study is going to answer: What are the changes of the spinopelvic parameters during different Muslim prayer positions?

The spinopelvic relationship refers to the intricate and dynamic interaction between the spine and the pelvis, which plays a crucial role in maintaining posture, balance, and overall musculoskeletal function. The alignment and movement of the spine and pelvis are interdependent, with changes in one structure often influencing the other. Understanding this relationship is essential for diagnosing, managing, and treating various spinal and pelvic conditions; furthermore, these parameters profoundly affect acetabular cup positioning and could affect dislocation rate after total hip arthroplasty.

Evaluating the normal spinopelvic parameters for any particular population is the first step toward detecting abnormal relationships, these were evaluated in various populations, such as Indian, Brazilian, Korean, and Caucasians.

Besides the deficiency of such reports from our area (Middle East), most of the published reports evaluated the change in spinopelvic relationship by evaluating the differences occurring from standing to 90 degrees sitting positions, which ignores most of the positions occurring during Muslim prayer, which necessitates more flexion of the hips and spine during specific position such as prostration (sujud). Activities that involve dynamic movements, such as Muslim prayer positions, can influence spinopelvic parameters. The sequence of postures in Muslim prayers, which includes standing, bowing, and kneeling, places unique demands on the spinopelvic alignment. Understanding how these positions affect spinopelvic parameters is essential for providing insights into the potential implications for musculoskeletal health, particularly in populations that engage in these activities regularly; furthermore, the possibility of proceeding with prayers after THA surgery if the dislocation risk due to impingement is low. What are the changes of the spinopelvic parameters during different Muslim prayer positions and if these changes are different between males and females and if these parameters are affected by participants' body habits, mainly the Body Mass Index (BMI).

Inclusion Criteria:

Adult participants (18 to 55 years old) who are willing to volunteer to participate in the study, reporting performing prayer positions without difficulty, had no hip or spine surgeries or complaints (pain or stiffness)

Exclusion Criteria:

• Participants refusing to volunteer.
• Participants who are not able to perform prayer positions comfortably.
• Those who had prior spine or hip surgeries.

Volunteers who are working at our hospital or visiting the out patient clinic who are willing to participate to the study without any consequences after explaining for them the purpose and any harms of the study.