Popliteal Plexus Block for Postoperative Pain After ACL Reconstruction

The Effect of the Popliteal Plexus Block on Postoperative Pain After Reconstruction of the Anterior Cruciate Ligament

The study aims to investigate the effect of the popliteal plexus block (PPB) on postoperative pain in patients undergoing anterior cruciate ligament (ACL) reconstruction.

Postoperative pain following ACL reconstruction can be alleviated with an ultrasound-guided femoral triangle block (FTB). However, it is the investigators' observation that 10-20 % of the patients still complain of intense pain localized in the center of the knee.

Cadaver dissection studies have shown that an injection into the distal part of the adductor canal will spread to the popliteal fossa, and one dissection study showed consistent spread to the popliteal plexus.

The study team hypothesized that a PPB will reduce the postoperative pain, when it is used as a supplement to the FTB in patients undergoing ACL reconstruction.

Inclusion Criteria:

• Patients undergoing ACL reconstruction on one of the two trial sites
• Age ≥ 18
• American Society of Anesthesiologists (ASA) status I-III
• Informed consent

Exclusion Criteria:

• Patients unable to cooperate
• Patients not able to speak Danish or with other communication problems
• Pregnancy
• Contraindication towards any medical product used in the study
• Preoperatively reduced sensation on the medial and lateral part of the lower leg
• Patients with diabetes requiring medical treatment
• Preoperative intake of opioids (dosed > once daily)
• ACL revision