Article by Dr Paul Batman, PhD.

DESCRIPTION:

The sartorius is the tailor’s muscle because it is the muscle used in crossing the legs, a position that tailors would take up to perform their job. It is the longest fusiform muscle in the body and is capable of a greater contraction than any other muscle. It runs diagonally across the thigh. It lies between two layers of fascia on the thigh and curves around the medial side passing behind the medial condyle and then forward to its insertion.

ORIGIN:

The anterior superior iliac spine, the notch between the anterior superior iliac spine and the anterior inferior iliac spine.

INSERTION:

Anterior medial tibial surface.

MUSCLE GROUPS:

The sartorius belongs to the following muscle groups:

Hip joint flexors, knee joint flexors, pelvic girdle forward tiltors, hip joint abductors (helping)

STRENGTHENING EXERCISES:

Hanging straight leg raise ( this muscle works best in hip joint flexion when the knee is extended), leg curl.

CASE STUDY STRENGTHENING EXERCISE: HANGING STRAIGHT LEG RAISE.

1.    Grasp a high bar with a pronated grip (to prevent swinging), with hands slightly wider than shoulder width apart

2.    Allow your body to hang steady

3.    From this starting position inhale and hold your breath slightly more than usual. Slowly raise your straight legs in front of your body by contracting the hip flexors and the abdominals

4.    Raise the legs until they are parallel to the ground

5.    Exhale and lower your legs back to the starting position

STRETCHING EXERCISES:

Kneeling flexor stretch, side lunge stretch.

CASE STUDY STRETCHING EXERCISE: KNEELING FLEXOR STRETCH.

1.    Kneel down with your left foot forward and right knee and right knee on the ground

2.    Keep your body upright and place your hands on your hips

3.    Gently rock back onto your right knee and tighten your abdominals

4.    With your abdominals contracted slowly move your trunk forward toward your left foot

5.    Move as far forward as you need to feel the stretch in the front of your thigh

6.    Hold the stretch for approximately 20 seconds and then return to your starting position

7.    Repeat the stretch with your  right foot forward and your left knee on the ground

PALPATION:

The sartorius muscle can be palpated close to the anterior superior iliac spine during hip joint flexion.

TRAINERS TIPS:

1.    Variations in the insertion of this muscle is well known. In some individuals it can serve as a knee joint extensor when its insertion is anterior to the knee joints axis.

2.    The sartorius plays a strong stabilizing role in knee joint extension by pulling the knee joint together.

3.    Its weakest contraction occurs when the hip joint and knee joint flex at the same time. This can be seen in a bent knee raise where the hip and knee joint simultaneously flex.

4.    In a supine leg curl, the sartorius combined with the hamstrings is moderately used. In a seated leg curl the sartorius involvement is increased dramatically.

5.    In a hack squat with the feet under the body, the sartorius is involved, possibly because of the rotation at the knee joint.