Ultrasonographic Evaluation of the Sciatic Nerve in Patients With Piriformis Syndrome

NCT06783439 | Completed DMC

• 2 other identifiers: 2024-69Istanbul PMR
• Study Type: observational
• Target: 19
• Locations: 1 country
• Sites: 1

Brief Summary

Piriformis syndrome (PS) is defined as a neuropathy of entrapment resulting from compression and irritation of the sciatic nerve at the level of the piriformis muscle (PM) at the pelvic outlet, causing sciatica radiating to the leg. The neuropathic component of PS is the compression of the sciatic nerve in or around the PM, while the primary cause of the somatic component is myofascial pain of the PM. PS accounts for 6-8% of all hip and sciatic pain cases. It is more common in middle-aged patients, and the most common etiological cause is trauma. There are various methods for the diagnosis of Piriformis Syndrome. Clinically, tenderness on palpation of the PM is the most common symptom. The FAIR test (passive flexion abduction and internal rotation of the hip), the Freiberg test (forceful internal rotation of the thigh in the supine position), the Pace test (abduction of the leg against resistance while sitting) and the Beatty maneuver (active abduction of the thigh on the affected side in the lateral decubitus position) are maneuvers that help in diagnosis. It is known that there is a delay in proximal nerve conduction (H-reflex) on the pathological side compared to the healthy side in the FAIR maneuver on EMG in PS, and it is not a sufficient test for diagnosis alone. Some studies have reported increased piriformis thickness on the pathological side in MRI. None of these clinical and imaging methods are sufficient for diagnosis alone, and today ultrasonography (US) has become one of the most important imaging methods for musculoskeletal clinicians in the diagnosis of PS. Imaging with US and the diagnostic injection test applied to the piriformis muscle with US guidance are quite important for diagnosis. There are a number of studies in the literature evaluating PM with US. These studies have shown that the piriformis muscle thickness and echogenicity increase on the pathological side. However, there is a lack of studies in the literature focusing on the evaluation of the sciatic nerve with US in patients with PS. Our aim in this study is to compare the thickness of the PM and the sciatic nerve by measuring US on both the pathological and painless sides in patients with unilateral hip pain who were diagnosed with PS clinically, to record the variations present in the sciatic nerve, and to determine whether the myofascial pain or the neuropathic component is dominant in the disease.

Conditions

Sciatica; Piriformis Muscle Syndrome

Keywords

Piriformis Muscle Syndrome; Sciatica

Outcome Measures

Primary Outcomes (3)

• numeric scale

  Tenderness in the piriformis muscle will be assessed by palpation using the numerical scale (NRS). The numerical scale is a pain score and is evaluated between 0 and 10.

  five months

• Sciatic nerve thickness (measurement with US)

  Sciatic nerve thickness will be measured with ultrasound on the symptomatic and asymptomatic sides in the same patient.

  five months

• Piriformis muscle thickness (measurement with US)

  Piriformis muscle thickness will be measured with ultrasound on the symptomatic and asymptomatic sides in the same patient.

  five months

Study Arms (2)

symptomatic hip

Patients aged between 18 and 70 years with unilateral hip and/or leg pain, positive FAIR (flexion, adduction, internal rotation) test, and tenderness to palpation in the PM will be included in our study.

Other: Ultrasound

asymptomatic hip

Patients aged between 18 and 70 years with unilateral hip and/or leg pain, positive FAIR (flexion, adduction, internal rotation) test, and tenderness to palpation in the PM will be included in our study.

Other: Ultrasound

Interventions

Ultrasound OTHER

The ultrasound probe will be placed parallel to the body of the piriformis muscle on an imaginary line drawn from the sacrum to the greater trochanter of the femur. This area is also the sensitive area of the patients during the examination with pressure, and when the US probe is in this position, the subcutaneous fat tissue, gluteus maximus muscle, piriformis muscle, and the upper and lower borders of the sciatic nerve will be displayed in order from superficial to deep. First, the maximum thickness of the piriformis muscle body will be measured, then the thickness of the sciatic nerve will be measured, and the same measurements will be applied to the patient's asymptomatic hip, and the measurements will be recorded.

asymptomatic hip; symptomatic hip

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Patients aged between 18 and 70 years with unilateral hip and/or leg pain, positive FAIR (flexion, adduction, internal rotation) test, and tenderness to palpation in the PM will be included in our study.

You may qualify if:

• Patients aged between 18 and 70 years with unilateral hip and/or leg pain
• Positive FAIR (flexion, adduction, internal rotation) test
• Tenderness to palpation in the Piriformis muscle

You may not qualify if:

• Patients with a history of previous surgery involving the lumbar and/or hip region
• A history of malignancy or infection in the pelvic region
• Body mass index (BMI) Greater than 30 kg/m2
• Psychiatric diseases
• Vascular disease
• Uncontrolled diabetes, hypertension or heart failure,
• Disc pathologies that may cause radiculopathy
• History of rheumatic disease.

Sponsors & Collaborators

• Istanbul University - Cerrahpasa: lead
• Istanbul Physical Medicine Rehabilitation Training and Research Hospital: collaborator

Study Sites (1)

İstanbul Üniversitesi - Cerrahpasa (IUC)

Istanbul, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Sciatica; Piriformis Muscle Syndrome

Interventions

High-Energy Shock Waves

Condition Hierarchy (Ancestors)

Sciatic Neuropathy; Mononeuropathies; Peripheral Nervous System Diseases; Neuromuscular Diseases; Nervous System Diseases; Neuralgia; Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Nerve Compression Syndromes; Pelvic Pain

Intervention Hierarchy (Ancestors)

Ultrasonic Waves; Sound; Radiation, Nonionizing; Radiation; Physical Phenomena

Study Officials

• Selim Sezikli

  Istanbul Physical Medicine Rehabilitation Training and Research Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: CROSS SECTIONAL
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: medical doctor

Study Record Dates

• First Submitted: January 7, 2025
• First Posted: January 20, 2025
• Study Start: December 1, 2024
• Primary Completion: April 1, 2025
• Study Completion: April 1, 2025
• Last Updated: March 3, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)