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Tag: Hand Muscles

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General Hands

Hand Muscle Anatomy: How Many Muscles are in the Hand?

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Have you ever really stopped to think about how spectacular your hands are? You use them for just about everything in life — from pumping iron at the gym to pumping gas at the gas station. They can be flat, or they can be clenched into fists. You can wiggle your fingers all around, bend them, and use them to point at someone. Our hands are truly a thing of beauty; there aren’t many other areas of our bodies that can take so many different forms. Just how many muscles are in the hand to enable all this power?

The hand muscle anatomy is very intricate, understandably, and most of the hand movements are actually controlled by the forearms.

How Many Muscles are in the Hand?

There are about 30 hand muscles, most of which lead to the wrists and forearms.

The formal terms for the various types of hand muscles are:

  • Dorsal interossei and palmar interossei muscles
  • Lumbrical muscles
  • Hypothenar muscles, which include abductor, flexor, and opponens digiti minimi
  • Thenar muscles, which include abductor pollicis brevis, flexor pollicis brevis, and opponens pollicis muscles

Technically, there are no muscles in the fingers, with the exceptions of the adductor pollicis and abductor pollicis longus at the base of the thumb.

How many muscles are in the hand? About 30 muscles are in the human hand, including lumbrical muscles as shown in this graphic.
Lumbrical muscles

If that all sounds rather foreign to you, don’t worry. We’ll explain.

1. The interosseous muscles are a network of muscles found on and in between the knuckles that enable us to bend the joints in the fingers. The dorsal muscles are used to spread the fingers, while the palmar muscles are used to bend them.

There are four dorsal interosseous muscles in each hand.

Palmar interossei consist of four muscles each that attach to the first, second, fourth, and fifth fingers. The third finger does not have a palmar interosseous muscle.

2. The lumbrical hand muscles extend to underneath each finger. We use them to straighten our fingers and bend the joints. There are four in each hand.

3. The three muscles on the side of each of your hands near the small finger are the hypothenar muscles. They enable you to move the pinky away from the ring finger, bend the pinky, and make a fist.

4. The thenar muscles are perhaps the most recognizable. They are three short muscles in the thick area of your palm under your thumb. These muscles give the thumb the ability to move the way it does, as well as enable us to grasp items.  (If you’re interested in an additional nugget of medical trivia, the bulge under your thumb is known as hypothenar eminence.)

5. The two muscles near the thumb, the adductor pollicis and abductor pollicis longus, enable us to pinch. One is located between the index finger and thumb, and the other passes through the wrist.

Possible Causes of Hand Muscle Pain

If you are reviewing the anatomy of the hand because you are feeling pain in your hand muscles, you may wish to learn about the most common causes of this pain. They include inflammation, nerve damage, basic overuse, and sprains, fractures, or other traumatic injuries.

Chronic health conditions also can lead to hand pain. They include:

If you have pain in your hand, see our hand specialist at our Warren, West Bloomfield, Macomb Township, or Howell office. Dr. Arora can analyze the skin, joints, and muscles of the hand and recommend tests to identify the source.

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General

What are the Muscles in the Human Hand?

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Pop quiz: How many muscles do you have in your fingers? If you said, “Zero! That’s a trick question,” you’ve got our number. Your fingers contain no “muscles” at all. They’re actually controlled by muscles in your hands and arms that are connected to your fingers by tendons. So what are the muscles in the human hand?

Following are some of the basics you might want to know, especially if you’re experiencing pain in your hands, wrists, or fingers.

Muscles in the Human Hand

1. Interossei (Dorsal and Palmar)

You know the old trick of determining how many days are in a month by counting on your knuckles and the grooves between them? Well, the shorter months land in the area of the interossei muscles. All these muscles serve the same purpose, which is to bend the joints. The “dorsal interossei” muscles, however, allow us to spread out fingers, while we close them together with the “palmar interossei” muscles.

2. Lumbricals

The lumbrical muscles in the human hand can be found under each finger. They allow us to straighten our fingers and bend the joints.

3. Hypothenar

The hypothenar muscle group is located on the small finger side of the hand. This muscle group enables the small finger to bend and pull away from the ring finger. It also allows us to make a fist, as well as bring the small finger toward the thumb.

The muscles within this group are:

  • Abductor digiti minimi
  • Flexor digiti minimi
  • Opponens digiti minimi

4. Thenar

The thenar muscle group is located in the bulky area under your thumb. The muscles enable the thumb to move in multiple directions, bend, and rotate. Without these muscles, we couldn’t grasp items.

Muscles in this group are:

  • Abductor pollicis brevis
  • Flexor pollicis brevis
  • Opponens pollicis

The Thumb Exception

Although there are no muscles in the fingers, two muscles can be found near the thumb: the adductor pollicis and the abductor pollicis longus.

The first is located between the index finger and thumb, and the second passes through the wrist. We couldn’t pinch without them.

Seeking Treatment

If you have carpal tunnel syndrome, cubital tunnel syndrome, or other hand or wrist conditions, they can cause pain in and around any of these muscles.

If you are experiencing pain or swelling in your hand, wrist, or fingers, make an appointment to see our hand surgeon in Macomb Township, Howell, Warren, or West Bloomfield.

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Dr. Aroras office from my first call to schedule my appointment was friendly. Walking in the first day, I felt like I was in a nice atmosphere. Dr. Arora was EXCELLENT in taking great care of my hand injury. He was gentle and very understanding to the concerns I had about my hand. His expertise was admirable and I would recommend anyone with an injury to their hand to his office to be under his care. Because of him, I have healed faster than expected and will make an 100% recovery! Thank you Dr.

Jackie S.

I first thought I was going to have to have painful injections or surgery, but Dr. Arora suggested physical therapy may do the trick. I was doubtful, but I agreed to do it. Now, my pain is gone, and with the help of an ergonomic keyboard at work to keep my hands in the correct position, I am virtually pain free. The therapy strengthened my wrists and shoulders, and built more flexibility into my wrists.

Jerry T.

My experience with this doctor was positive from the outset. Dr. Arora was kind and spent a great deal of time with me. Staff was friendly. The office was nice and bright.

Ariel G.

Very friendly and helpful Great staff!!! Doctor Arora was very professional and did great work. I was very happy with everything!

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