Parasacral Ischial Plane Block in Lower Extremity Surgery

NCT07594197 | Not Yet Recruiting

• 1 other identifier: BursaYIERH-AR-ND-01
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

The parasacral ischial plane block is a novel fascial plane approach targeting the sacral plexus. This technique is technically less challenging and eliminates the requirement for direct visualization of the sacral plexus. The aim of this prospective observational study is to evaluate the efficacy of the conventional sacral plexus block versus the parasacral ischial plane block in patients undergoing lower extremity surgery.

Conditions

Ages 18-80; ASA I-III; Patients Operated on Under Regional Anesthesia; Patients Who Provided Written Informed Consent; Patients Scheduled for Elective Lower Extremity Surgery

Keywords

Lumbosacral Plexus; Anesthesia, Conduction; Postoperative Pain

Outcome Measures

Primary Outcomes (1)

• Sensory and motor block onset time

  This approach is based on the volume-dependent spread of local anesthetic into the plane between the sacral plexus and the deep pelvic muscle fascia; sensory blockade begins proximally to distally within 10-20 minutes, while motor blockade usually develops later and gradually around 20-30 minutes.

  1 hour

Secondary Outcomes (1)

• The Numerical Rating Scale (NRS)

  1 Day

Study Arms (2)

Parasacral Ischial Plan Block

ACTIVE COMPARATOR

A novel ultrasound-guided fascial plane approach to the sacral plexus, called the Parasacral-Ischial Plane (PIP) block, has been successfully studied in a small number of patients. The sacral plexus is located within a fascial plane formed by the pelvic fascia anteriorly, the sacrum medially, the piriformis and gluteus maximus muscles posteriorly, and the ischium laterally. The piriformis muscle has no attachment to the ischium and attaches to the greater trochanter laterally. A fascial plane exists between the piriformis muscle and the ischium; this fascial plane extends to the sacral plexus. Venkataraju et al. stated that in a PIP block demonstration, the needle should be directed and placed towards the posteromedial surface of the ischium. After bone contact, medication was injected, and it was observed that the medication spread from under the piriformis muscle towards the sacral plexus. This method is considered easier and less risky.

Procedure: Parasacral Ischial Plan Block

Sacral plexus block

ACTIVE COMPARATOR

This block, defined by the parasacral approach, targets the exit point of the plexus at the level of the foramen ischiadicum majus. Unlike distal sciatic blocks, blocking at this level includes the posterior cutaneous femoral nerve, superior/inferior gluteal nerve, and pudendal nerve, along with the ischial nerve. In current practice, ultrasonography (USG) has become the "gold standard"; visualizing the neural structures deep to the piriformis muscle by placing the probe between the lateral sacrum and the iliac wing increases the success rate while minimizing the risk of complications.

Procedure: Sacral plexus block

Interventions

Parasacral Ischial Plan Block PROCEDURE

The sacral plexus is located within a fascial plane formed by the pelvic fascia anteriorly, the sacrum medially, the piriformis and gluteus maximus muscles posteriorly, and the ischium laterally. The piriformis muscle has no attachment to the ischium and attaches to the greater trochanter laterally. A fascial plane exists between the piriformis muscle and the ischium; this fascial plane extends to the sacral plexus. Venkataraju et al. stated that in PIP block demonstrations, the needle should be directed and placed towards the posteromedial surface of the ischium. After bone contact, the medication was injected, and it was observed that the medication spread from under the piriformis muscle towards the sacral plexus.

Parasacral Ischial Plan Block

Sacral plexus block PROCEDURE

This block, defined by the parasacral approach, targets the exit point of the plexus at the level of the foramen ischiadicum majus. Unlike distal sciatic blocks, blocking at this level includes the posterior cutaneous femoral nerve, superior/inferior gluteal nerve, and pudendal nerve, along with the ischial nerve. In current practice, ultrasonography (USG) has become the "gold standard"; visualizing the neural structures deep to the piriformis muscle by placing the probe between the lateral sacrum and the iliac wing increases the success rate while minimizing the risk of complications.

Sacral plexus block

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Ages 18-80
• ASA I-III
• Patients operated on under regional anesthesia
• Patients who provided written informed consent
• Patients scheduled for elective lower extremity surgery -

You may not qualify if:

• Patients with a history of allergy to local anesthetic drugs
• Patients with coagulation disorders
• Patients with BMI \> 40 kg/m²
• Presence of infection at the block application site
• Chronic pain syndrome (chronic opioid use)
• Pregnant women
• Patients who cannot be communicated with
• Patients requiring emergency surgery -

Sponsors & Collaborators

• Bursa Yuksek Ihtisas Training and Research Hospital: lead

Study Sites (1)

Bursa High Specialization Training and Research Hospital

Bursa, Yildirim, 16300, Turkey (Türkiye)

Location

Related Publications (6)

• Enneking FK, Chan V, Greger J, Hadzic A, Lang SA, Horlocker TT. Lower-extremity peripheral nerve blockade: essentials of our current understanding. Reg Anesth Pain Med. 2005 Jan-Feb;30(1):4-35. doi: 10.1016/j.rapm.2004.10.002. No abstract available.

  PMID: 15690265 BACKGROUND

• Zhao J, Huang Y, Fu M, Tao F. Ultrasound-guided suprainguinal fascia iliaca block combined with a sacral plexus block for lower extremity surgery: A case report. Medicine (Baltimore). 2020 Aug 28;99(35):e21921. doi: 10.1097/MD.0000000000021921.

  PMID: 32871928 BACKGROUND

• Arjun BK, Prijith RS, Sreeraghu GM, Narendrababu MC. Ultrasound-guided popliteal sciatic and adductor canal block for below-knee surgeries in high-risk patients. Indian J Anaesth. 2019 Aug;63(8):635-639. doi: 10.4103/ija.IJA_296_19.

  PMID: 31462809 BACKGROUND

• Chia N, Low TC, Poon KH. Peripheral nerve blocks for lower limb surgery--a choice anaesthetic technique for patients with a recent myocardial infarction? Singapore Med J. 2002 Nov;43(11):583-6.

  PMID: 12680529 BACKGROUND

• Bech B, Melchiors J, Borglum J, Jensen K. The successful use of peripheral nerve blocks for femoral amputation. Acta Anaesthesiol Scand. 2009 Feb;53(2):257-60. doi: 10.1111/j.1399-6576.2008.01859.x.

  PMID: 19175579 BACKGROUND

• Venkataraju A, Narayanan M, Phillips S. Parasacral ischial plane (PIP) block: An easy approach to sacral plexus. J Clin Anesth. 2020 Feb;59:103-105. doi: 10.1016/j.jclinane.2019.06.030. Epub 2019 Jul 16. No abstract available.

  PMID: 31323463 BACKGROUND

MeSH Terms

Conditions

Pain, Postoperative

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Study Officials

• Korgün Ökmen

  Bursa Yuksek Ihtisas Training and Research Hospital

  STUDY DIRECTOR

Central Study Contacts

NURULLAH DAMLA

CONTACT

+905075482122; nurullahdamla@hotmail.com

Korgün Ökmen, professor

CONTACT

+905057081021; korgunokmen@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: RESEARCH ASSISTANT

Model Details: Comparison of methods between 2 groups.

Study Record Dates

• First Submitted: May 5, 2026
• First Posted: May 18, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): May 1, 2027
• Last Updated: May 18, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)