Abduction is a movement that moves a bone, organ, or part of an organ away from the median plane of the body. There are, thus, abductor muscles located at the hip, shoulder, or thumb, for the main ones. Unlike an adductor muscle that produces an adduction movement, thus bringing a member closer to the median plane of the body, the abductor makes it possible to move it away.
The most common condition affecting these muscles is tendonitis, also known as tendinopathy. Specific strength exercises can strengthen these abductors.
Anatomy of abductor muscles
Abduction is the movement of a limb or segment of a limb away from the axis of the body. The abductor muscles are therefore able to cause abduction. Abduction movements are essential, especially when it comes to the thumb, as well as the shoulder and hip joints.
Abductor muscles of the thumb
The long abductor of the thumb
Elongated and flattened, it goes down and out. It passes at the level of the posterior surface of the radius and then at the level of its lateral face, where it is fleshy. Above the wrist, it then becomes tendinous and superficial. It is accompanied and attached to the short extensor of the thumb. It fits at the base of the first metacarpal.
The short abductor of the thumb
Flat, elongated, and triangular, it is located under the skin. It slightly covers the short flexor of the thumb.
Abductor muscles of the hip
- The Gluteus maximus muscle also called gluteal Maximus: is the largest muscle of the buttock, which forms the curve of the buttock. Composed of a deep plane and a superficial plane, it is abductive only by its highest beams. It is thick, losangic and its fibers are parallel, with an oblique path down and out;
- Tensor muscle of the Fascia Lata: it is an elongated muscle, stretched from the coxal bone to the shin;
- Gluteus medius muscle: It has a triangular appearance, and it is stretched from the coxal bone to the femur;
- Gluteus minor muscle: triangular in appearance, it is stretched from the coxal bone to the femur and has a fan shape;
- Piriformis: It is a pelvitrocherian muscle stretched from the sacrum to the femur and triangular in appearance;
- The “pelvic triceps” (internal obturator and the upper and lower twins): these are three trochanteric pelvic muscles, stretched from the coxal bone to the femur. Their appearance is triangular.
Abductor muscles of the shoulder
The shoulder includes many muscles. The one that mainly ensures the abduction of the arm, by allowing it to be lifted outwards, is called the spinous muscle, or supraspinatus muscle.
It has a triangular prismatic shape and divides into two bundles, an anterior one which is the most important, and a posterior one. It is, in fact, in synergy with the deltoid muscle that it intervenes in this abduction movement of the shoulder. The deltoid consists of three bundles, anterior (or clavicular), middle (or acromial), and posterior (called spinal).
Abductor muscle physiology
The abductor muscles of the thumb play a role in the opposition of the thumb. Thus, in dynamics, they are abductors of the thumb and are allowed to bring the first metacarpal forward.
They are also slightly abductors of the wrist and flexors of the wrist. In addition, the short abductor of the thumb makes it possible to spread the first metacarpal relative to the second.
Regarding the abductor muscles of the hip, abduction is the movement in which the thigh deviates from the axis of the pelvis. The amplitude of this movement is between 35 and 45 degrees and depends on age. This movement is allowed by a number of muscles in the gluteal region and in particular by the gluteus medius muscle.
- Gluteus maximus muscle: According to some authors, it participates in the abduction of the hip by its upper fibers (as well as in the adduction by its inner fibers);
- tensor muscle of the Fascia Lata: its action, in dynamic mode, at the hip, allows flexion, abduction, as medial rotation;
- gluteus medius muscle: This is the main abductor muscle of the hip. It has high efficiency, especially due to the fact that its steering is almost perpendicular to its lever arm;
- Gluteus minimus muscle: It allows flexion as well as hip abduction. However, it is three times less powerful on hip abduction than gluteus medius;
- Piriformis: In dynamic mode, it allows hip rotation of up to 45 degrees of flexion. At 45 degrees of hip flexion, it is abductive;
- “Triceps pelvic”: They are used, in particular, for lateral hip rotation up to 90 degrees of flexion. At 90 degrees of flexion, they are then abductors of the hip.
The shoulder abduction movement, enabled by the supraspinatus muscle in synergy with the deltoid muscle, consists of elevating the arm and carrying it out of the body. Many sports require the repetition of this movement that fully solicits the supraspinatus muscle, such as swimming, tennis, volleyball, and shot put.
Are there abnormalities, or pathologies related to the abductor muscles?
The most common pathology related to the abductor muscles, especially in athletes and footballers, is tendonitis, caused by a brutal and repeated solicitation of the joints concerned. Indeed, during intense sports, the abductor muscles, whether those of the shoulder or those of the hip, are frequently the target of tendinopathy.
In fact, the tendon is the extension of a muscle: indeed, each muscle has one or more tendons, which connect it to a bone body. Usually very resistant, this rope is formed of collagen fibers. When these tendons are overused, their inflammation can occur: tendonitis, also called tendinopathy, occurs.
There are multiple causes of tendonitis. Here are the most common ones:
- Insufficient warm-up. Indeed, it prepares the muscles and tendons for effort and must therefore always last between 15 and 20 minutes, depending on the heat. The risk is greater in winter;
- insufficient recovery. Thus, a good recovery is essential after exercise to reduce fatigue, but also to improve sports performance. This includes good sleep as well as muscle and mental relaxation;
- the lack of progressive training;
- inadequate or insufficient stretching;
- incorrect technical gestures;
- unsuitable equipment;
- a change of training ground with the harder or softer ground;
- poor hydration and nutrition;
- poor posture or prolonged maintenance of the same position;
- recurrent microtrauma of the tendon.
Poorly treated, or even ignored, tendonitis can cause a sprain or even a tendon rupture. So do not take this kind of pain lightly and consult a doctor quickly.
It is an ultrasound that makes it possible to establish a diagnosis of tendinopathy. Thus, for the abductor muscles of the hip, for example, ultrasound of the musculotendinous structure inserted on the greater trochanter (tensor muscle of the fascia lata, piriformis muscle, small and medium gluteal muscles, twin muscles, and internal obturator) will help identify possible tendonitis.
Similarly, with regard to shoulder tendonitis, it is the doctor’s examination associated with an ultrasound of the muscular cuff that will give an accurate diagnosis of the affected tendons.
What treatments in case of problems related to the abductor muscles
For the treatment of tendonitis affecting the abductor muscles, multidisciplinary management will often be required, requiring the intervention of a physiotherapist, a podiatrist, or even an osteopath. Here, according to osteopath Charline Defaux, practicing in Versailles, the main steps to follow to treat tendonitis are as follows:
- Resting, for at least three weeks, then a gradual resumption of activity;
- in case of severe pain, apply cold, three times a day for fifteen minutes;
- respect the inflammatory phase by not taking anti-inflammatory drugs during the first three days;
- practice a specific warm-up;
- practice stretching adapted to pain;
- Hydrate well by drinking 1.5 liters of water per day: indeed, if drainage is not sufficient, deposits may form on the tendons;
- favor alkalizing elements;
- master the technical gestures of sports exercises;
- Bring quality and adapted equipment.
Finally, it should be noted, moreover, that the strengthening of the abductor muscles of the hips, and in particular the gluteal medius, makes it possible to relieve a complex and difficult-to-treat pathology that is a patellofemoral syndrome, a pathology characterized in particular by previous knee pain.
This muscular strengthening of the gluteus medius thus appears to be the best way to fight against the leg collapse of the lower limb, responsible for many pathologies affecting the musculoskeletal system. It is therefore a new rehabilitation strategy, supported and validated by scientific studies.
Muscle your abductors
Well-muscled, hip abductors provide good support for the pelvis. Among the different ways to strengthen the abductors of the legs, the simplest is to use the method of work of the abductor lying down.
For this, it is enough to lie on your side, legs parallel to the floor and hands to the ground. Then, it is necessary to lift an outstretched leg with the help of the muscles, and this, for many repetitions, before performing the same movement with the other leg.
Regarding the shoulders, strength exercises aim to strengthen them, not to achieve more muscle volume, but to make the shoulder stable, strong, mobile and reactive. An example to strengthen these abductors is an exercise that consists of putting a rubber band in tension at the hip, before pulling it outwards with the arm extended.
Another exercise suggests fixing the elastic to your foot, putting it in tension at the pelvis. It is then necessary to raise the arm outstretched forward to shoulder height, control the descent, and then raise the outstretched arm to shoulder height. Yet another exercise: hitting targets.
Thus, in the pump position, and while nine targets are distributed around you, at arm’s distance, it will be necessary to hit the targets one by one by always going back through the pump position.
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