The Sciatic Nerve

I’ve had many clients come to me over the years requesting help with sciatic-type pain; either after having been diagnosed with “sciatica” or from assuming that it could be such. Unfortunately, it’s been made very clear to me that many people—the healthcare industry included—aren’t aware that discrepancies in certain muscles could mimic sciatica. I’m not at all saying that true sciatica couldn’t be the case, but my goal is to provide you with additional information to consider when it comes to the sciatic nerve, the muscles around it, and how PNMT can help you to become pain-free. First I’ll start off with the anatomy and then I’ll go into other details.

The sciatic nerve, which is the longest nerve in the body, is actually comprised of two nerves—tibial and common fibular (a.k.a. common peroneal)—which splits into two divisions, usually at the knee. Per Tortora & Derrickson (11th Edition), the nerve root origin is as follows…

  • Sciatic: L4, L5, S1, S2, S3
  • Tibial: L4, L5, S1, S2, S3
  • Common Fibular: L4, L5, S1, S2
    * (Click here for a dermatome chart: dermatome meaning the area of skin that provides sensory input to the central nervous system.)

As the sciatic nerve descends down the thigh, it sends branches to the hamstring muscles and the adductor magnus. At the knee, the distribution to additional muscles is as follows…

  • Tibial: Gastrocnemius, plantaris, soleus, popliteus, tibialis posterior, flexor digitorum longus, and flexor hallucis longus. It then divides into the medial plantar and lateral plantar branches:
    – Medial Plantar: Abductor hallucis, flexor digitorum brevis, and flexor hallucis brevis.
    – Lateral Plantar: Quadratus plantae, abductor digiti minimi, flexor digiti minimi brevis, three lateral lumbricals, dorsal interossei, plantar interossei, and adductor hallicus.
  • Common Fibular: Divides into the superficial fibular and deep fibular branches:
    – Superficial Fibular: Fibularis longus and fibularis brevis.
    – Deep Fibular: Tibialis anterior, extensor halluscis longus, fibularis tertius, extensor digitorum longus, and extensor digitorum brevis.

What could happen when the sciatic nerve is affected? Well, here’s what Tortora & Derrickson stated in their 11th Edition book…

Sciatic nerve injury, the most common form of back pain, is caused by compression or irritation of the sciatic nerve. Pain may extend from the buttock down the posterior and lateral aspect of the leg and the lateral aspect of the foot. It may be injured because of a herniated (slipped) disc, dislocated hip, osteoarthritis of the lumbosacral spine, pressure from the uterus during pregnancy, inflammation, irritation, or an improperly administered gluteal intramuscular injection.

To take it a step further and per my Precision Neural Mobilization training manual, a normal response from the sciatic nerve during a deep stretch, for example, could result in a sensation down the posterior thigh which may extend into the calf and foot. On the other hand, there are indications and causative factors that could result in abnormal responses. They are as follows…

Now back to some muscles and PNMT….

The gluteus minimuspiriformis, and hamstrings are a few muscles that can mimic sciatica. Trigger points (click here and here for previous posts on TrP’s—and please note that the muscles below, in bold, link to webpages that show TrP referral patterns) in the gluteus minimus can refer pain all the way down the side of the leg; usually stemming from the anterior fibers. TrP’s in the piriformis can send pain from the buttocks down the back of the thigh; however, the pain doesn’t go past the knee—it is also well known for its ability to entrap the sciatic nerve, so any tightness will produce sciatic symptoms. TrP’s in the hamstrings can also send pain down the back of the thigh. Travell reports that there are “rare” cases where the sciatic nerve is entrapped between two heads of the hamstring attachments on the ischial tuberosity; however, this study by Kari Saikku, Jarkko Vasenius, and Pekka Saar from the University Central Hospital in Helsinki, Finland found that this sort of entrapment “is not extremely rare.”

At the end of the day, muscular discrepancies within the muscular-skeletal system can in fact mimic sciatic-type symptoms—and I want you to be aware of this, especially if you have tried every other option out there to no avail. There are more holistic and non-invasive approaches to treating pain and dysfunction, and PNMT is a prime example. By taking just a few measurements to see how a person’s body is aligned, a trained therapist can ascertain what muscles are pulling where, and treat the affected muscles to help the individual to become pain-free again.

Sounds awesome, doesn’t it?

As always, I hope you find this information informative… And more importantly, HAPPY NEW YEAR!

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“Neutral balance alignment is key to becoming pain free!”™ ~ Me

 

The QL: Another Player In Back Pain

In a previous post, I went over the psoas major and how it is a major player in back pain, so today I thought I would go over the QL—the quadratus lumborum, which is a common source of low back pain. Before I go on though, let’s go over the anatomy…

THE ANATOMY (per Tortora & Derrickson, 11th edition)
Origin: Iliac crest and iliolumbar ligament.
Insertion: Inferior border of 12th rib and first four lumbar vertebrae.
Action: Acting together, pull 12th ribs inferiorly during forced exhalation, fix 12th ribs to prevent their elevation during deep inhalation, and help extend lumbar portion of vertebral column; acting singly, laterally flex vertebral column, especially lumbar portion.
Innervation: Thoracic spinal nerve T12 and lumbar spinal nerves L1-L3 or L1-L4.

The QL is a very strong lateral flexor and lateral stabilizer of the trunk; working synergistically with the psoas—on the same side—in lateral stabilization. It also assists the multifidi, erector spinae, and serratus posterior inferior in extension.

So, how do you know when the QL could be influencing back pain? Well, here are a few indicators for treatment…

  • Persistent pain, even at rest
  • Back pain after a violent sneeze or cough
  • Great pain when turning from one side of the body to the other while in bed
  • Excruciating pain when laterally bending or during forward flexion
  • Pain when standing; however, putting bilateral pressure above both iliac crests lessens the pain
  • Hyperlordosis is present.

If you experience one or more of the aforementioned, there is a good chance the QL is a player in your back pain—low back, specifically.

As always, I hope you find this information to be informative!

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“Neutral balance alignment is key to becoming pain free!”™ ~ Me

The Psoas Major: A Major Player In Back Pain

Have you ever had back pain or know someone who has? If so, this post is for you, my friends!

There are many muscles that could cause back issues, but today I’m going to focus on just one, that being the psoas major; mainly because I’ve come across too many new clients whom never had them treated before… And this surprises me. Another reason is because I’ve noticed that many people think that only back muscles should treated because it’s their “back that hurts”. Believe it or not though, there are muscles in the front of our body that have an effect on back pain as well. Before I go on though, let’s go over the anatomy…

THE ANATOMY (per Tortora & Derrickson, 11th edition)
Origin: Transverse processes and bodies of lumbar vertebrae.
Insertion: With iliacus into lesser trochanter of femur.
Action: Psoas major and iliacus, acting together, flex thigh at hip joint, rotate thigh laterally, and flex trunk on the hip.
Innervation: Lumbar spinal nerves L2-L3.

NOTE: Some people refer to this muscle as the “iliopsoas” because the psoas major and iliacus share a common tendon and end-point, but they are in-fact two separate muscles, which is why I’m only going to refer to the psoas; however, they do work in-conjunction, in some circumstances.

The function of the psoas is to increase flexion of the thigh at the hip. It can either bring the femur towards the spine or the spine towards the femur; just depends on what movement is taking place. An example of when it would be active—or contracting—is when you swing your leg forward during walking or running. The psoas is also a strong lateral flexor and stabilizer of the vertebral column (ipsilaterally—same side); as in when you bend to one side or the other.

How do you know when the psoas could be influencing back pain? Well, let me share a few examples—which also happen to be indicators for treatment—with you…

  • You have back pain when lying on your back; without a pillow under your knees
  • You have back pain that is vertical, but is relieved when in the reclining position
  • You have difficulty straightening after prolonged sitting

Taking it one step further, let me share some additional indicators for treatment with you…

  • An increase—or possible decrease—in your lordotic curve
  • You stand with your weight off the affected psoas side
  • You have unexplained pelvic floor pain (neural entrapment issues)
  • You have rotational distortions of the spine (Scoliosis)
  • You have groin pain

Please keep in mind that muscles have synergists and antagonists, so even though you have this information at your fingertips, there are other muscles not mentioned in this post that can cause a person pain and dysfunction in the back; anywhere in the body, really.

As always, I hope you find this information to be informative!

IMPORTANT NOTE: The psoas is a deep muscle in the abdominal area and great caution should be of utmost concern when treating this muscle. I mention this because of the possible presence of an AAA—Abdominal Aortic Aneurysm—which would be a serious contraindication for treatment, due to the fact that it could have potentially disastrous consequences.

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“Neutral balance alignment is key to becoming pain free!”™ ~ Me

Muscle Contractions

In this rather lengthy post, I’d like to go over muscle contractions and their types; isotonic (concentric and eccentric) and isometric. However, before I delve into each contraction specifically, I’m going to start off by providing a very watered-down version of an anatomy and physiology lesson in regards to our muscular system from a cellular level. For the record, I am not an A&P professional… Just thought I would use this opportunity to brush-up on some facts that I learned back in ’06. In fact, I probably learned this sometime between ’90 and ’93, but who remembers such detail from almost 20-years ago and while in high school. Hahaha! 🙂

Skeletal muscle tissue—which produce body movements, stabilize body positions, store and move substances within the body, and generate heat—is made up of hundreds to thousands of cells, also called muscle fibers. Muscle fibers consist of sarcomeres, which are made up of thick filaments, thin filaments, and Z discs; among other things. In order for muscle fibers to contract, certain proteins must be present; two of those being actin and myosin. Check out this link for visual aids and here is where you can read more about this in detail.

Okay, enough A&P for now! I’m a layman so onward with layman terms regarding the functions of skeletal muscles, that being muscle contractions. While the muscle is under tension, it may shorten, lengthen, or remain the same…

Muscle contractions are classified as being either isotonic or isometric. An isotonic contraction (iso- = equal; -tonic = tension) happens when tension developed by the muscle remains almost constant while the muscle changes its length. These contractions are used for body movements and for moving objects. The two types are known as concentric and eccentric.

Concentric isotonic contractions happen when two ends of a muscle are brought closer together during the contraction. The muscle shortens and pulls on another structure, such as a tendon, to produce movement and to reduce the angle at the joint. An example of a concentric isotonic contraction is when one does a bicep curl. As the dumbbell is lifted up, visualize how the two ends of the bicep move closer together during the contraction. This is the simplest form of contraction and is usually the least problematic.

Now imagine one lowering the dumbbell after the bicep curl. It is with this movement that the previously shortened bicep now lengthens during the contraction, which is known as an eccentric isotonic contraction. The bicep in this example contracts so it can control the speed at which the dumbbell is lowered. Per Tortora & Derrickson, 11th edition, repeated eccentric isotonic contractions produce more muscle damage and more DOMS (delayed-onset muscle soreness) than concentric isotonic contractions.

Isometric contractions happen when a muscle contracts but the ends do not move at all, and even though they do not result in body movement, energy is still expended. Isometric contractions are vital because they stabilize some joints as others are being moved. They maintain posture and support objects in fixed positions. The perfect example would be me sitting at the computer typing this right now. I’m sitting erect trying to use good posture and my mid-back is starting to hurt… Ugh! My lower trapezius is sustaining a contraction—to hold me upright—and it is becoming too much. At no time have the ends of the muscle come closer together. Make sense? I bet all of you have experienced this at one time or another.

There is one more category that should be mentioned, that of approximation; the length-tension relationship. If two ends of a muscle are brought closer together, over time, the muscle will adjust its length to keep the same tension. While not a true contraction, it acts like one. This is the concept of Davis’ LawWhen two ends of a muscle are brought together, the pull of tonus is increased. When two ends of a muscle are separated, tonus is lessened or lost, thereby weakening the muscle.

The first part of Davis’ Law has to do with adaptive-shortening. Unless something acts upon the shortened muscle, it will remain in the shortened position and adapt that position as the new “normal”. It will then resist attempts to return to the old “normal” as it has forgotten what that position was.

The second part of Davis’ Law has to do with stretch-weakeness. Muscles are affected by either duration or magnitude. Stretch-weakness is definitely a factor of duration, not magnitude. Having a shoulder much lower than the other for a short period of time is not as powerful as having a small difference for a long period of time.

It is through this length-tension relationship that PNMT comes in handy. These discrepancies within the muscles can cause pain and dysfunction. That being said, proper measurement from a Certified Precision Neuromuscular Therapist can help verify whether your pain and/or dysfunction is caused by misalignment within the muscular-skeletal system.

I hope this information has been informative!

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“Neutral balance alignment is key to becoming pain free!”™ ~ Me

The Infraspinatus Muscle

In my last post, Trigger Points (TrP’s) In Detail, I briefly mentioned a TrP in the infraspinatus and thought I would go ahead and write about this muscle more thoroughly since it is a big player with shoulder issues.

THE ANATOMY (per Tortora & Derrickson, 11th edition)
Origin: Infraspinous fossa of scapula.
Insertion: Greater tubercle of humerus.
Action: Laterally rotates and adducts arm at shoulder joint.
Innervation: Suprascapular nerve.

The infraspinatus is one of the four deep muscles that join the scapula to the humerus. The four tendons merge together to form the rotator cuff. The rotator cuff strengthens and stabilizes the shoulder joint and is comprised of the supraspinatus, infraspinatus, teres minor, and subscapularis; think S-I-t-S (small “t” representing the teres minor–not major).

The prime function of the infraspinatus is to decelerate forward motion of the humerus. Repetitive movements with the arm in over-the-head positions—such as in throwing a baseball, a tennis serve, spiking a volleyball, and swimming—can result in injuries. This happens because much of the work of the infraspinatus is done in eccentric contraction. Eccentric contraction is when the muscle fibers lengthen during contraction… More on muscle contractions in my next post.

Great info, Nicole, but how does one know if the infraspinatus needs some TLC from a CPNMT (Certified Precision Neuromuscular Therapist)?

LOL! That last sentence is so ridiculous. 🙂

Well, some general indicators for treatment could include, but are not limited to:
1) Difficulty brushing or combing your hair;
2) Inability to sleep on your side at night;
3) Inability to reach behind your back and touch the opposite shoulder blade.

There are other—more medical—indicators for treatment, which is why I recommend contacting myself or another CPNMT for an evaluation if you are experiencing problems within the shoulder girdle.

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“Neutral balance alignment is key to becoming pain free!”™ ~ Me