Popliteal Nerve Block for Acute Achilles Tendon Rupture Repair Surgery

Women's College Hospital80 enrolled

Overview

Achilles tendon rupture is common, yet the value of popliteal nerve block for postoperative pain control during surgical repair remains uncertain. Despite widespread use, evidence supporting its analgesic effectiveness is limited, and both popliteal nerve block and Achilles tendon repair carry risks of nerve injury. This randomized, placebo-controlled trial will evaluate whether adding a popliteal nerve block to standard systemic analgesia improves postoperative pain and reduces opioid use in patients undergoing acute Achilles tendon rupture repair. Secondary outcomes will examine the incidence and impact of nerve complications on recovery, including return to physical activity and functional performance.

This will be a prospective, double-blinded, randomized controlled superiority trial conducted at Women's College Hospital (WCH). The study aims to enroll 80 patients (40 per group) undergoing ambulatory surgical repair of acute Achilles tendon ruptures.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

Conditions

Acute Achilles Tendon Rupture

Interventions

Under ultrasound guidance, a 22G, 80-mm echogenic needle (SonoTAP II, Pajunk Medical Systems, USA) will be inserted using an in-plane lateral-to-medial approach. 30 mL of 0.5% ropivacaine with 2.5 µg/ml of epinephrine will be deposited between tibial and common peroneal nerves within the paraneural sheath. Adequate spread of local anesthetics will be confirmed by visualization of paraneural spread.

Sham BlockPROCEDURE

Patients in the Control group will receive sham blocks using a 25G needle to inject 1 mL of saline subcutaneously in the same location (popliteus of the surgical knee). Sterilization and ultrasound scanning will match actual PN block. Such a non-invasive placebo allows maintaining patient blinding, while reducing the risks associated with high-volume placebo nerve block injections. The ultrasound screen will be blinded from the patient's vision for all patients in the trial to prevent unblinding by patients with knowledge of the technique.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age 18 - 65 * ASA classification: I - III * BMI \< 35 kg/m2 * Undergoing acute Achilles tendon rupture repair surgery as a day surgery procedure Exclusion Criteria: * Pre-existing neurological deficits or peripheral neuropathy in the distribution of the tibial or common peroneal nerves * Local infection * Contraindication to regional anesthesia (e.g., bleeding diathesis, coagulopathy) * History of use of over 30 mg oxycodone or equivalent per day * Contraindication to any component of a standard multi-modal analgesia * Allergy to local anesthetics * History of significant psychiatric conditions that may affect patient assessment * Pregnancy * Inability to provide informed consent * Patient refusal of popliteal nerve blockade * Prior Achilles tendon surgeries on the operative leg * Unable to speak or read English

Outcomes

Primary Outcomes

Cumulative Opioid Consumption

Total opioid dose administered to each patient, converted to oral morphine equivalents.

Time frame: The first 24 hours after surgery

Secondary Outcomes

Area Under the Curve for Postoperative Pain

Area under the curve calculated from discrete Numeric Rating Scale evaluations of postoperative pain (0 - 10), where 0 corresponds to no pain, and 10 corresponds to the worst pain imaginable. Pain will be measured on this scale at 0, 6, 12, 18, and 24 hours after surgery.

Time frame: The first 24 hours after surgery

Quality of Recovery

Quality of recovery evaluated using the QoR-15 scale (0 - 150), where 0 represents extremely poor recovery and 150 represents excellent recovery.

Time frame: At baseline, 6, 24, 48 hours, 7 days and 1-year post-surgery

Postoperative Pain Score

Measured using the Numeric Rating (NRS) Scale (0 - 10) where 0 corresponds to no pain, and 10 corresponds to the worst pain imaginable.

Time frame: At baseline, 0, 6, 12, 18, 24, 36, 48 hours, 7 days and 1-year post-surgery.

Intraoperative Opioid Consumption

Measurement of opioids administered during surgery, converted into oral morphine equivalents.

Time frame: The first 24 hours after surgery

Time to Analgesic Request

Length of time until the patient's first request for analgesics following surgery.

Time frame: The first 24 hours after surgery

Time to Discharge

The length of time each patient stays in Phase I (Postanesthesia Care Unit) and Phase II (Surgical Day Care) after surgery.

Time frame: The first 24 hours after surgery

Adverse Events Attributable to Popliteal Block

The incidence of adverse events possibly attributable to popliteal nerve block, including peripheral nerve injury, hematoma, and infection.

Time frame: At 0, 6, 12, 18, 24, 36, 48 hours, 7 days and 1-year post-surgery

Adverse Events Attributable to Opioids

The incidence of opioid-related side effects, including sedation, pruritis, nausea/vomiting, and respiratory depression.

Time frame: Evaluated at 24 and 48 hours after surgery.

Pain, fatigue, and physical function

Measured using the Achilles tendon Total Rupture Score (ATRS)

Time frame: Prior to surgery and 1-year post-surgery

Neuropathic pain

Measured using the English version of the Douleur Neuropathique 4 (DN4) Questionnaire

Time frame: At 1 week and 1-year post-surgery

Popliteal Nerve Block for Acute Achilles Tendon Rupture Repair Surgery

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts