Comparative Effects of PIR and PFS on Pain, Hip ROM, and Disability in Piriformis Syndrome (PIR-PFS RCT)

University of Faisalabad

Status: Completed

Conditions: Piriformis Syndrome

Treatments: Procedure: Post Isometric Relaxation (PIR); Procedure: Post Facilitation Stretching (PFS)

Study type: Interventional

Funder types: Other

Identifiers

NCT07255053

TUF-PIRIFORMIS-RCT-2025

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 36 patients

Sex: All

Ages: 35 to 55 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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36 participants in 2 patient groups

Post Isometric Relaxation (PIR)

Experimental group

Description:

Type of technique: Muscle Energy Technique (MET) Patient position: Supine, affected leg flexed at hip and knee, crossed over the other leg, foot resting on the table Pelvis stabilization: Therapist hand on opposite ASIS to prevent pelvic movement Leg positioning: Other hand on lateral aspect of the knee Finding the barrier: Knee moved into abduction until first sign of resistance (pain-free end range) Isometric contraction: Patient pushes against the therapist's hand at \~20% strength for 7-10 seconds Relaxation and stretch: After contraction, leg moved slightly further into abduction Repetitions: 3 times per session

Treatment:

Procedure: Post Isometric Relaxation (PIR)

Post Facilitation Stretching (PFS)

Experimental group

Description:

Patient position: Supine, affected leg slightly adducted and externally rotated, hip flexed \>60° Therapist hand placement: Inferior hand on table for support, superior hand guides leg movement Muscle positioning: Piriformis placed in intermediate range (between full stretch and rest) Isometric contraction: Patient externally rotates leg against resistance for 10 seconds Pause / Rest phase: 30-second relaxation after contraction; therapist applies deeper stretch into adduction and external rotation Next barrier: Leg gently moved to new barrier Repetitions: 3 times per session

Treatment:

Procedure: Post Facilitation Stretching (PFS)