The biggest fear for patients undergoing knee replacement surgery is that persistent pain felt at the back of the knee postoperatively. While regional anesthesia is generally successful at numbing the front of the knee, managing pain in the posterior (back) area is not always easy. In this study, we tested a new method designed to alleviate pain in the back of the knee and improve patient comfort.

A New Solution for "Posterior" Pain After Knee Surgery To ensure patient comfort following knee replacement surgery, we routinely use ultrasound-guided injections of local anesthetics around the nerves of the knee to block pain signals. While this method is highly successful at eliminating pain in the anterior (front) part of the knee, studies have shown that the medication often fails to reach the deep posterior (back) compartments, leaving patients with persistent discomfort in that area.

In this study, we addressed a fundamental question: "How can we ensure the medication reaches those hard-to-access depths at the very back of the knee?"

To achieve this, we developed a simple yet highly effective technique. We applied a tourniquet-similar to a blood pressure cuff-to the upper leg and inflated it for a short period. We administered the medication, then released the tourniquet and performed a second application.

This controlled pressure on the upper leg acted as a barrier, preventing the anesthetic from migrating upward toward the groin and instead "pushing" it into the narrow passages at the back of the knee. By doing so, we enabled the medication to reach deep points that it typically cannot access on its own.

The Results:

As a result of this technique, we observed a significant reduction in stubborn posterior knee pain. Furthermore, our patients required substantially fewer potent painkillers (analgesics) during their recovery.

Inclusion Criteria Patients aged 40-85 years, with a BMI of 18-35 kg/m², and an ASA physical status of I-III who underwent total knee arthroplasty (TKA) under spinal anesthesia were included. Eligible participants were those who volunteered to participate and provided written informed consent.

Exclusion Criteria

To ensure methodological standardization, the following cases were excluded:

Patients undergoing revision surgery.

Those undergoing unicompartmental (unicondylar) knee replacement, as the severity of surgical trauma differs from total replacement.

Bilateral cases, to prevent potential bias in assessing postoperative opioid consumption and pain scores.

Additionally, patients were excluded if:

The surgical duration exceeded 180 minutes.

There was a known history of coagulopathy, peripheral neuropathy, or allergy to local anesthetics.

The spinal anesthesia was insufficient, requiring a conversion to general anesthesia.

Data Availability Statement: There are no plans to share individual participant data. Research findings will be reported as collective analyses in scientific journals and academic theses.

Patients' relatives helped them describe their pain