Popliteal Plexus Block for Total Knee Arthroplasty

University of Aarhus

Status and phase: Terminated; Phase 4

Conditions: Pain, Postoperative

Treatments: Other: Sodium Chloride 0.9 %; Drug: Bupivacaine-EPINEPHrine 0.5%-1:200,000 Injectable Solution

Study type: Interventional

Funder types: Other

Identifiers

NCT03439787

Protocol_PPB_TKA_31122017

2017-005180-40 (EudraCT Number)

Details and patient eligibility

About

This study aims to assess the analgesic effect of the popliteal plexus block as a supplement to a femoral triangle block in patients undergoing total knee arthroplasty

Full description

A femoral triangle block (FTB) effectively anesthetizes the anterior group of nerves innervating the knee (infrapatellar branch of the saphenous nerve, the medial femoral cutaneous nerve and the terminal branch of the medial vastus muscle nerve). However, the posterior group of nerves innervating the knee joint is not covered with an FTB, and therefore most patients complain of significant, opioid-requiring pain despite a successful FTB.

The posterior group consists of the popliteal plexus, which is derived from the tibial nerve and the posterior branch of the obturator nerve. The popliteal plexus is located in the popliteal fossa, where it entwines the popliteal artery and vein. Recent cadaver studies have suggested that an injection into the distal part of the adductor canal will spread to the popliteal fossa (PubMed Identifier (ID): 28937534; PubMed ID: 27442773).

This study aims to assess the analgesic effect of the popliteal plexus block (PPB) as a supplement to a femoral triangle block (FTB) after total knee arthroplasty (TKA).

In the study all patients will receive an FTB with 10 ml bupivacaine-epinephrine (0.5%-1:200,000) with the addition of 0.5 ml Dexamethasone (4 mg/ml).

All patients are postoperatively observed for the development of significant pain (NRS > 3) in the primary observation period (POP) defined as: a 3-hour observation period starting at the return of completely normal cutaneous sensation (lateral thigh and lateral side of the lower leg) after spinal anesthesia. If the patient reports pain (NRS > 3) in the POP, the patient will be randomized to the study treatment - a PPB with 10 ml bupivacaine-epinephrine or 10 ml saline.

Enrollment: 15 patients

Sex: All

Ages: 50+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Male or female at least 50 years of age at screening
• Scheduled to undergo primary total knee arthroplasty in spinal anesthesia
• Normal sensory function at the lateral part of the thigh and lower leg
• American Society of Anesthesiologists (ASA) physical status 1, 2, or 3
• Able to provide informed consent

Exclusion criteria

• Unable to cooperate and follow the study protocol
• Communication problems
• Allergic towards any medical product administered in the study
• Diabetes requiring medical treatment
• Pregnancy (a pregnancy test will be conducted on all women of childbearing potential prior to inclusion in the study. A positive test result will result in exclusion from the study)
• Preoperative opioid treatment (dosed > once daily)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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15 participants in 2 patient groups, including a placebo group

Active Popliteal Plexus Block

Active Comparator group

Description:

10 ml Bupivacaine-Epinephrine 0.5%-1:200,000 Injectable Solution

Treatment:

Drug: Bupivacaine-EPINEPHrine 0.5%-1:200,000 Injectable Solution

Placebo Popliteal Plexus Block

Placebo Comparator group

Description:

10 ml Sodium Chloride 0.9 %

Treatment:

Other: Sodium Chloride 0.9 %