Targeted Nerve Injection to the Knee (Nerve to Vastus Medialis): Comparing Two Adductor Canal Block Approaches

Study of Targeted Injection of Nerves to the Knee-A Volunteer Trial Evaluating Nerve to Vastus Medialis

Status

Not yet recruiting

Phases

Phase 4

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT07444827

Enrollment

Registered

2026-03-03

Start date

2027-01-01

Completion date

2027-12-01

Last updated

2026-08-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Anesthesia, Local

Keywords

Adductor canal block, Nerve to vastus medialis, Chloroprocaine, Knee joint

Brief summary

This randomized, double-blinded volunteer study compares two ways of performing the adductor canal (AC) nerve block at the mid-thigh to see which approach more reliably numbs the anteromedial knee. One approach is the traditional AC block placed near the saphenous nerve; the other separately targets the nerve to vastus medialis (NVM) in addition to the saphenous nerve. Healthy adult participants receive both blocks in one visit (one on each leg), with the order randomized. The primary outcome is change in quadriceps strength (a proxy for vastus medialis anesthesia) measured by load-cell dynamometry. Secondary outcomes include cutaneous sensory mapping (pinprick and cold) and the percentage of a standardized, marked knee-incision line covered by sensory block. The study uses ultrasound guidance and a standard dose of chloroprocaine, with routine monitoring to minimize risks.

Interventions

PROCEDURETraditional adductor canal block

Ultrasound-guided injection adjacent to the saphenous nerve; 20 mL of 2% chloroprocaine.

PROCEDURENVM (nerve to vastus medialis) targeted adductor canal block

Ultrasound-guided injection; 10 mL 2% chloroprocaine at the NVM (confirmed by nerve stimulation), plus 10 mL at the saphenous nerve.

DRUGChloroprocaine Injection

2% chloroprocaine

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* Age ≥18 years * Able to provide written informed consent * Able and willing to comply with study procedures and \~6-hour visit * American Society of Anesthesiologists (ASA) Physical Status 1 or 2 * Weight \>70 kg

Exclusion criteria

* BMI \>35 kg/m² * Use of analgesics within 24 hours before the procedure * History of thigh trauma or surgery * Pregnant or planning pregnancy * Lower extremity deformities/tattoos interfering with block performance * Systemic neuromuscular disease * Contraindications to regional anesthesia (e.g., infection, allergy, challenging sonoanatomy) * Other health conditions that would affect safe participation

Design outcomes

Primary

Measure	Time frame	Description
Quadriceps strength as measured by load cell dynamometer	Day 1	Load cell dynamometers are highly accurate portable electronic devices used to measure isometric muscle strength.

Secondary

Measure	Time frame	Description
Percentage of hypothetical incision covered	Day 1	An unblinded anesthesiologist will mark the mock total knee arthroplasty and the length of the hypothetical incision that has diminished sensation to pinprick will be determined.

Contacts

CONTACTAshley Burke

ashley.burke@duke.edu(919) 681-2849

PRINCIPAL_INVESTIGATORBrian Mendelson

Duke University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Aug 28, 2026