The aim of this study is to define the starting and ending points of the adductor canal in adductor canal block (ACB) applications through distance measurements relative to the anterior superior iliac spine (ASIS) and the adductor tubercle. These measurements are performed using ultrasound (USG) and correlated with cadaveric data.

Key research questions addressed include:

• Can the start and end points of the adductor canal be formulated along a line drawn between the ASIS and the adductor tubercle?
• Is there a definable relationship between the block application site and anatomical landmarks such as the vastoadductor membrane (VAM), the apex of the femoral triangle, and other adjacent structures that facilitates localization?

By validating ultrasound measurements with cadaveric findings, the study aims to provide researchers with a more predictable and reliable method for determining the optimal site for adductor canal block administration.

The aim of this study is to define the starting and ending points of the adductor canal (AC) in the context of adductor canal block (ACB) applications, through distance measurements related to the anterior superior iliac spine (ASIS) and adductor tubercle. These measurements are performed in two different planes: the first plane is along an imaginary line drawn between the ASIS and the femoral adductor tubercle, while the second plane is formed by the line between the ASIS and the base of the patella.

In these planes, distances were measured between the following points:

The distance between the adductor tubercle and ASIS,

The distance between ASIS and the base of the patella,

The distance between ASIS and the apex of the patella,

The distance between the midpoint of the inguinal fold and the base of the patella.

In patients, ultrasound was used to identify and mark the following anatomical points:

The apex of the iliopectineal fossa,

The first visible point of the vastoadductor membrane (VAM),

The point where the sartorius muscle ends with the intersection of the adductor longus and begins its contact with the edge of the adductor magnus point

The point where the adductor hiatus is located.

Additionally, in patients where visible, the descending genicular artery was also marked.

The position of the femoral artery in relation to the VAM (medial, middle, or lateral) was noted, as well as the location where the femoral artery intersects the adductor magnus and sartorius, and the depth from the skin to the adductor hiatus. Circumferential measurements of the thigh were also taken at these points.

Some of the data obtained was compared with anatomical measurements obtained through cadaveric dissection.

Key Research Questions

Where are the starting and ending points of the adductor canal?

Can the adductor canal be defined along a line drawn between the ASIS and the adductor tubercle?

Is there a definable relationship between the block application site and anatomical landmarks such as the vastoadductor membrane (VAM), the apex of the femoral triangle, and other adjacent structures that facilitate localization?

By validating ultrasound measurements with cadaveric findings, the study aims to provide researchers with a more predictable and reliable method for determining the optimal site for adductor canal block applications

Inclusion Criteria:

ASA 1-2-3 patients

BMI <35

Ages 18-65

Those willing to participate in the study

Exclusion Criteria:

Those unwilling to participate in the study

Pregnant women

BMI >35

ASA 4-5-6 patients

He study at Etlik City Hospital will include patients who meet the following criteria: ASA classification of 1, 2, or 3, indicating individuals who are healthy or have mild to moderate systemic disease without major functional limitation; a BMI below 35 to exclude participants with obesity-related comorbidities; and an age range of 18 to 65 to ensure a broad yet controlled sample while avoiding age-related confounding factors. All participants must also provide informed consent, confirming their understanding of the study's purpose, procedures, and potential risks.