The Hip Abductors

n order to achieve efficient and pain-free movement, the muscles that support each joint must be balanced. Any imbalance in the musculature that supports a joint will lead to abnormal compensatory motion along with the increased potential for pain. Therefore, as a trainer, it is important to understand the function of all the muscles that support each joint. It is also important to understand how an isolated muscle weakness can negatively affect functional movement.

This series of articles will identify and define the function of the muscles that support each major joint in the body. The series also will address how muscles work in synergy with one another to create efficient movement at each joint. This month we begin with the major stabilizing muscles of the hip. Successive articles will progress through the lower body, the trunk and then finalize with the neck and shoulder joint.

1. The gluteus medius lies deep next to the gluteus maximus on the lateral side of the hip. The muscle is split into three separate fiber groups, and each fiber group has a unique functional component.

2. The gluteus minimus is the deepest of the gluteal muscles, lying next to the gluteus medius. The gluteus minimus muscle is split into two separate groups of fibers: anterior and posterior. Like the fibers of the gluteus medius, the primary function of both groups of fibers is abduction of the thigh. With their similar fiber alignment and
points of attachment, the gluteus minimus’ function is similar to that of the gluteus medius.

As noted, the gluteus medius and minimus play a primary role in frontal plane motion at the hip. It is important to note that other synergistic muscles must work in conjunction with these gluteal muscles to achieve efficient motion while maintaining hip stability. Dependent on hip position, the tensor fascia latae (TFL) and the piriformis each act as synergists in hip abduction.

The primary function of the TFL is hip flexion; however, its secondary component of motion involves hip abduction and internal rotation. This functional component enables the TFL to work as a direct synergist to the anterior fibers of the medius and minimus.

The piriformis also has a role in hip abduction. When moving toward 60 degrees of hip flexion, the piriformis changes its function from an external rotator to become primarily a hip abductor.

For efficiency of motion in hip abduction, these muscles must all work together or the plane of motion will
be altered. Since each of these muscles attains a component of rotation or flexion-extension, any weakness will cause a deviation specific to the plane of the dominant muscle. If muscular imbalances are not addressed, they will be reinforced with exercise as dominant muscles compensate for weak muscles.

The primary philosophy behind muscle activation techniques is that muscle tightness is secondary to muscle weakness. When the body recognizes instability, the natural protective tendency
is to tighten up. For example, when we walk on ice, the body recognizes instability and attempts to protect itself through a hypercontraction of the muscles throughout the body.

A similar process occurs when the body recognizes muscle weakness: The body senses instability in the joint that the weak muscle should be supporting, causing a protective shortening of the antagonist muscle group. Addressing muscle weaknesses will prevent the stretched muscles from continually tightening up again.

Since range of motion (ROM) limitations are typically a result of muscle weaknesses, a ROM exam identifies muscular weaknesses within the body.

Muscle weaknesses typically show
up in the position where the muscle is most shortened. This is also the position that the antagonist muscle would prevent the joint from attaining if the muscle is tight. Therefore, if a position of joint motion cannot be achieved, then the muscle that places the joint in that position is weak. l

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Gluteus MediusGluteus Minimusposterior fibersmiddle fibersposterior fibersanterior fibersanterior fibersThe Hip Abductors: Origin, Insertion and Action
Gluteus Medius Origin: Insertion: Primary Action: Closed-Chain Action:
Anterior Fibers outer surface of ilium lateral/superior and hip abduction with stabilize the pelvis
below iliac crest posterior surface of internal rotation of in the frontal plane
(split in 3 separate greater trochanter the femur
divisions)

Middle Fibers outer surface of ilium lateral/superior and hip abduction stabilize the pelvis
below iliac crest posterior surface of in the frontal plane
(split in 3 separate greater trochanter
divisions)

Posterior Fibers outer surface of ilium lateral/superior and hip abduction with stabilize the pelvis
below iliac crest posterior surface of external rotation of in the frontal plane
(split in 3 separate greater trochanter the femur
divisions)

Gluteus Minimus Origin: Insertion: Primary Action: Closed-Chain Action:
Anterior Fibers outer-middle portion anterior border of hip abduction with stabilize the pelvis
of ilium greater trochanter internal rotation of in the frontal plane
the femur

Posterior Fibers outer-middle portion anterior border of hip abduction with stabilize the pelvis
of ilium greater trochanter external rotation of in the frontal plane
the femur

IDEA PERSONAL Trainer march 2002 fine anatomy

When recommending strengthening exercises for the gluteus medius and minimus, consider the muscles’ functions in both the open and the closed chain. Regarding the muscles’
role in the closed chain (weight bearing), the muscles must be strong enough to perform their desired functions. Since the medius
and minimus act as lateral stabilizers on the weight-bearing leg in any single-leg motion, these muscles must possess adequate isolated strength in order to resist the forces transmitted to the hip through gravity and ground reaction forces. This demands significant strength even for normal functional movements. Therefore, the progression of exercises must take this into consideration.

Begin with isolated strengthening exercises for two to three weeks followed by weight-bearing exercises for lateral stability. It is important to note that the following exercises are designed to improve proprioception.

The primary goal is to increase the muscles’ ability to contract through full ROM.
Therefore, with the isolated (open-chain) exercises, work the muscles into the shortened range and emphasize the components of rotation.

In order to improve neurological input, emphasize control with the following exercises, and perform a high number of repetitions to provide neurological reinforcement. The client should perform three sets of 20 repetitions of each exercise. Rest intervals between sets should be no longer than one minute.

1. Side-Lying Leg Lifts: This is a great beginner’s exercise for clients with significant weakness in any of the hip abductors. The primary goal is to improve general strength
in hip abduction.

Performance

Compensations

2. Hip Abduction With Tension Band of Cable: This is the second open-chain exercise, which is designed to isolate the specific fibers of the hip abductors. This is also a great exercise for a client who demonstrates significant weakness in hip abductors.

It is designed to strengthen the abductors on the non-weight-bearing leg. Emphasize the eccentric control with each repetition.

Performance: Gluteus Medius

Compensations

Performance: Gluteus Minimus

Note: The gluteus medius is the dominant hip abductor involved in all exercises for hip abduction; however, due to a more anterior position of alignment, by flexing the hip during this exercise, the gluteus minimus becomes more involved.

Compensations

3. Hip Hike

• : This is a the first weight-bearing exercise designed to strengthen
  the hip abductors in their role of preventing contralateral pelvic drop in the frontal plane.

Note that the weight-bearing leg is the leg being strengthened.

Performance

Compensations

4. Two-Way Pull With Tension Band

• :
  This weight-bearing exercise is designed to strengthen the hip abductors in their role of hip stabilization.

Performance

Step 1:

Step 2:

Compensations

5. One-Leg Squats With Unbalanced Load

• : This weight-bearing exercise also is designed to strengthen the hip abductors in their role of maintaining pelvic balance.

Performance

Compensations

• Any exercise performed in single-leg stance is not recommended until there is adequate isolated strength of the hip abductor muscles, as evidenced by the ability to perform all sets and reps of side-lying exercise.

3 IDEA PERSONAL Trainer march 2002

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5IDEA PERSONAL Trainer march 2002 fine anatomy

The following tests are indicators of muscle weakness in the particular divisions of the gluteus medius and gluteus minimus. Client lies on back, while trainer grasps one ankle at a time (keep knees extended) and checks ROM. Do not look for a specific degree of motion, as each individual’s ROM differs. Do focus on symmetry, however, as asymmetries commonly are tied to hip problems, sacroiliac joint dysfunction and low-back discomfort. The asymmetries relate to the muscle weakness noted in each test. When muscle weaknesses are identified, a trainer can more efficiently design an exercise program.

1. Perform with straight leg, hip abduction (30 degrees), checking ROM for internal rotation of the femur.

Limitation in motion represents weakness of the anterior fibers of
the gluteus medius.

2. Perform with straight leg, hip abduction (30 degrees), checking ROM for external rotation of the femur.

Limitation in motion represents weakness of the posterior fibers of the gluteus medius.

3. Perform with straight leg, hip flexion (30 degrees), abduction (20 degrees), checking ROM for internal rotation of the femur.

Limitation in motion represents weakness of the anterior fibers of the gluteus minimus.

4. Perform with straight leg, hip flexion (30 degrees), abduction (20 degrees), checking ROM for external rotation of the femur.

Limitation in motion represents weakness of the anterior fibers of the gluteus minimus.

IDEA PERSONAL Trainer march 2002IDEA PERSONAL Trainer march 2002 IDEA PERSONAL Trainer march 2002