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Completed

NCT Number: NCT07255053

Comparative Effects of PIR and PFS on Pain, Hip ROM, and Disability in Piriformis Syndrome

This randomized clinical trial evaluates the effectiveness of Post-Isometric Relaxation (PIR) and Post-Facilitation Stretching (PFS) for managing pain, improving hip abduction and internal rotation, and enhancing functional capacity in patients with Piriformis Syndrome. Thirty-six participants will be assessed at baseline and six weeks using pain scores, hip range of motion, and functional scales to determine which technique provides superior outcomes.

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Key information

Age range

35 year–55 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

The University of Faisalabad

Faisalābad, Punjab Province, 38000, Pakistan

About this study

Piriformis Syndrome (PS) is a musculoskeletal condition characterized by pain in the buttock and hip, sometimes radiating to the lower back and thigh. It may arise from anatomical variations affecting the sciatic nerve, inflammation, hypertrophy, muscle spasms, or shortening of the piriformis muscle. PS can significantly reduce hip range of motion and functional capacity, affecting patients' quality of life.

This randomized clinical trial aimed to compare the effectiveness of two rehabilitation techniques, Post-Isometric Relaxation (PIR) and Post-Facilitation Stretching (PFS), in managing pain, improving hip abduction and internal rotation, and enhancing functional capacity in patients with PS. Thirty-six participants aged 35-55 years, of both genders, diagnosed with sub-acute or chronic PS, and meeting specific clinical criteria, were randomly assigned to either intervention group.

Inclusion criteria

included positive findings on at least three of the following tests: Piriformis, Beatty, Freiberg, FAIR, Sign of Pace, and Nagel tonic external rotation of hip; bilateral buttock pain due to sciatic nerve or piriformis muscle spasm; NPRS pain score of 3-7; tenderness over the sciatic foramen; and willingness to participate. Exclusion criteria included spinal, hip, knee, or SI joint pathology, prior spinal surgery or vertebral fracture, systemic disease, limb length discrepancy, postural deformities (e.g., scoliosis), hip dislocation or femoral fracture, and any psychological conditions.

Group A (PIR) participants performed exercises lying supine with the affected leg flexed, pelvis stabilized, and piriformis muscle activated through resisted abduction. Group B (PFS) participants performed combined stretching and isometric contractions with the involved leg positioned in hip flexion, adduction, and external rotation. Interventions were conducted over a 4-week period.

Assessments were conducted at baseline and six weeks using:

Numeric Pain Rating Scale (NPRS) to quantify pain intensity

Goniometer - to measure hip abduction and internal rotation range

Lower Extremity Functional Scale (LEFS) to assess functional disability; a 20-item scale rated on a Likert scale (total score 0-80), with lower scores indicating greater disability

The objective of this study was to determine which rehabilitation technique, PIR or PFS, is more effective in alleviating pain, improving hip range of motion, and enhancing functional outcomes, ultimately aiming to improve the quality of life for patients diagnosed with Piriformis Syndrome.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Participants aged 35-55 years Both genders Positive findings on three or more of the following tests: Piriformis, Beatty, Freiberg, FAIR, Sign of Pace, Nagel tonic external rotation of hip Bilateral buttock pain caused by compression of the sciatic nerve or piriformis muscle spasm NPRS pain score between 3 and 7 Tenderness to palpation over the sciatic foramen Diagnosed sub-acute or chronic Piriformis Syndrome Willing to participate

Exclusion criteria

  • Any pathology or recent injury around the hip, knee, or SI joint, or radiating pain from the spine, SI joint, or hip History of spinal surgery or vertebral fracture History of systemic disease, stroke, leprosy, or amputation Leg pain not related to Piriformis Syndrome (e.g., disc herniation, sacroiliac joint dysfunction, degenerative joint disease) History of spinal injury, joint disease, or congenital abnormalities Limb length difference SI joint dysfunction Hip joint dislocation or femoral fracture Any postural deformity or anomaly (e.g., scoliosis) Psychologically diagnosed condition

Treatment and study plan

Post Isometric Relaxation (PIR)

Procedure

Participants received PIR exercises targeting the piriformis muscle three days per week for 4 weeks. The technique involved pain-free isometric contractions followed by gentle stretching to improve hip abduction and internal rotation

Other names: Muscle Energy Technique (MET)

Post Facilitation Stretching (PFS)

Procedure

Participants received PFS exercises targeting the piriformis muscle three days per week for 4 weeks. The technique combined isometric contractions with controlled stretching to enhance hip mobility and reduce pain.

Other names: Muscle Energy Technique (MET)

Primary outcomes

  1. Pain intensity in patients with Piriformis Syndrome

    Time frame: Baseline and 4 weeks after intervention completion

    Pain was measured using the Numeric Pain Rating Scale (NPRS), a 0-10 scale where 0 indicates no pain and 10 indicates worst possible pain.

Secondary outcomes

  1. Hip Abduction and Internal Rotation Range of Motion

    Time frame: Baseline and 4 weeks after intervention completion

    Hip range of motion was measured using a goniometer to assess internal rotation and abduction angles.

  2. Functional Disability

    Time frame: Baseline and at 4 weeks after intervention completion

    Functional capacity was assessed using the Lower Extremity Functional Scale (LEFS), a 20-item questionnaire evaluating lower limb function in daily activities. Lower scores indicate greater disability

Sponsors and collaborators

Lead sponsor

University of Faisalabad

Other

Registry information

Official study title

Comparative Effects of Post Isometric Relaxation and Post Facilitation Stretching on Pain Reduction Hip Abduction and Internal Rotation Range, and Functional Disability in Patients With Piriformis Syndrome

Acronym: PIR-PFS RCT

Important dates

Study start
2025
Primary completion
2025
Study completion
2025
First posted
Nov 28, 2025
Registry last updated
Nov 28, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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