Inverted supinator reflex & its relevance to the manual therapist explained

Osteopaths like many other manual therapists such as chiropractors and physiotherapists have become known as specialists in back pain. For this reason, conditions such as spondylitis and spondylarthrosis are commonly seen by these practitioners, both of which can lead to compressive cervical myelopathy, compression of the spinal cord in the neck. Needless to say, osteopaths, physiotherapists and chiropractors must be familiar with the neurological tests that help differentially diagnose causes of neck and arm pain. In the upper limb it is less the sensory tests and more the motor tests and reflexes that help the osteopath to identify nerve root compression. The inverted supinator reflex is probably the the most important clinical sign that an osteopath, physiotherapist or chiropractor can illicit to decide whether there is spinal cord and spinal root compression. It is pathognomonic of cervical myelopathy at the level of C5/C6. In this article I will try and help the manual therapist; osteopath, physiotherapist and chiropractor the professions that use spinal manipulation, to understand the physiology of the inverted supinator reflex in order to appreciate its significance when treating patients.

One of the most common types of extra-dural cord compression (compression occurring outside of the dura matar) that an osteopath, physiotherapist or chiropractor is likely to come across is caused by spondylotic change, that is, spondylotic compressive myelopathy. Since the majority of movement in the cervical spine is focused between the levels of C5 and C6 vertebrae it is at this level that arthritic changes most frequently occur. At this level, On x-ray it is common to find a cervical bar due to disc degeneration, spondylosis, a posterior longitudinal ligament which is buckled, thickened and calcified and osteophytosis protruding into and narrowing the spinal canal. However, osteophytic changes narrowing the vertebral canal are unlikely to be limited to the spinal canal alone. It is likely that there will also be narrowing of the intervertebral foramen simultaneously due to thinning of the vertebral disc and thickening of the ligamentum flavum. The result of this is both compression of the spinal cord and compression of the nerve roots.

The osteopath must therefore be aware that any patient suffering with nerve root symptoms attributed to degeneration of the cervical spine, such as pain down the arm into the thumb, must be examined in order to exclude any long-track or spinal cord damage. It is for this reason that patients suffering with suspected cervical spine degeneration and nerve root symptoms in the upper limb must always be asked whether they also have leg symptoms such as heaviness, stiffness, difficulty climbing up stairs, tight band-like feelings (dorsal columns), a sensation of standing on a vibrating floor (dorsal columns), a sensation that water is running down the legs (spinothalamic tract) or pins and needles that don't conform to a nerve root pattern.

In addition to questioning the patient, the clearest indication of both nerve root and spinal cord compression in the cervical spine is displayed by the inverted supinator reflex. By tapping the brachioradialis tendon at the styloid process of the radius a force is sent down the bone, irritating the muscle spindles of all muscles at the front and back of the forearm, sending a message to the spinal cord, resulting in the reflex flexion of the forearm and fingers. The nerve roots responsible for elbow and finger flexion are C6 and C8 respectively. C7 however, responsible for elbow extension, is not activated despite its muscle spindles being irritated. This leads us to conclude that in a polysynaptic reflex, when a multitude of nerve roots are activated the reaction is for dominant nerve roots to react whilst others lie dormant.

Spondylosis, thinning of the disc between two vertebra causes compression of the nerve root between two vertebrae, deactivates its axons and gives other nerve roots, unaffected by compression, the opportunity to express themselves. In the event that there is also cord compression, an upper motor neuron lesion, above the level of the unaffected nerve roots, they will not only express themselves, they will be hyper-reactive. This explains the structural changes in the spine that result in an inverted supinator reflex. Bony changes of the intervertebral foramen between the vertebrae C5/C6 of the spinal column cause narrowing of the intervertebral foramen and compress the nerve root of C6 as it exits the spine causing a hypo-reflexive reaction from the nerve root C6. The bony changes in the form of a cervical bar, situated within the spinal canal at C5/C6 vertebrae, result in an upper motor lesion rendering everything below it hyper-reflexive. Therefore, C7, once dormant, now active, becomes hyper-reflexive as does C8. The result is an inverted supinator reflex, inverted because there is an absence of the C6 brachioradialis reflex and C7 is responsible for the elbow extension. One would also find a hyper-reflexive reaction at all reflexes on the same side of the body, that is, the knee jerk and ankle jerk reflex. One would also find clonus of the knee and ankle on the same side as well as an up-going planter response in-line with an upper motor neurons lesion.

This explains the pathophysiology of the the spinal column and the effect that altered structure can have on the nervous system. It should be clear why this sign is an important indicator for the osteopath, physiotherapist and chiropractor and GP as well as manual therapists using spinal manipulation Early identification of spondylotic compressive myelopathy can result in appropriate medical treatment being administered and avoids permanent neurological damage.

Danny Sher
Registered osteopath
Jerusalem: 14 Kaf Tet b'November Street
Modiin: Dimri Medical Center, 37 Yigal Yadin Street
02-561-1808
0522-606-774
Website: www.osteopath.co.il
Video: http://youtu.be/AxI2TfSatHE

www.osteopath.co.il

Sciatica and pregnancy - an osteopathic perspective

Osteopaths are not strangers to patients suffering with sciatica, however, when the patient suffering is pregnant a new set of conditions arise that may affect the sciatic nerve that need to be considered. The most obvious change affecting a pregnant woman is the increase in the size of the uterus.  As it expands the hip, pelvis and low back all have to adjust their position relative to one another in order to accommodate the increase in weight. This affects all the surrounding soft tissues. Since the sciatic nerve exits the lumber spine, enters the pelvis and continues its journey to the hip joint and into the  leg it is not surprising that osteopaths see pregnant women suffering with sciatica.  

The spinal cord and nerve roots are flexible neurological soft tissues and are normally able to stretch and curve around the bony structures of the spine and pelvis.  However, during the last 3 months of pregnancy as weight increases anteriorly for the pregnant woman, the lumber spine is pulled into extension narrowing the intervertebral foramen of the lumber spine and reducing the aperture through which the nerve roots of the sciatic nerve pass. Anyone who has a degree of stress through the sciatic nerve roots to begin with could start to feel leg pain as the pressure on the sciatic nerve increases. 

The glutei muscles are strong postural muscles that attach from the hips to the pelvis and sacrum. One of their functions is to keep the body upright, therefore as the center of gravity shifts anteriorly during pregnancy their workload increases and thus their tone. The sciatic nerve traverses the glutei muscles making it vulnerable to compression as it passes through the glutei muscles.  Once the hypertonia in the glutei muscles reaches a point where it compresses the sciatic nerve, there is hypoxia in the nerve and the pregnant patient may start to experience sciatic pain in the leg.

It is up to the osteopath to find out where along the path of the sciatic nerve, from the back to the leg, the sciatic nerve it is being compressed.  With some conservative osteopathic techniques the osteopath can take the stress off the spine, pelvis and surrounding muscles. The aim of the osteopath is to integrate the function of the muscles of the pelvis, hips and spine to encourage the body to make the transition smoothly.

The osteopathic treatment should be to allow the spine to shift according to changes in the center of gravity thus spreading out the weight equally and efficiently.  Furthermore the osteopath should aim to help the the hips and pelvis to anteriorly and posteriorly rotate dynamically and according to the changes in weight-bearing.

For more information:

http://www.osteopath.co.il/pregnancy-related-pain-heb.php

http://www.osteopath.co.il/pregnancy-related-pain.php

Danny Sher B.Sc (Hons) Ost. Is a registered osteopath in the UK and Israel.

He works in his clinics in Jerusalem and Modiin.

www.osteopath.co.il

Danny Sher

Registered osteopath

Jerusalem: 14 Kaf Tet b'November Street

Modiin: Dimri Medical Center, 37 Yigal Yadin Street

02-561-1808

0522606774

www.osteopath.co.il

Www.osteopath.co.il

Low pack, pelvic and pubic-symphysis pain during pregnancy - an osteopathic perspective

An osteopath treating the pregnant patient suffering with pelvic or low back pain must apply physiology and anatomy to a body in flux. Major weight increases, altered spinal curves and unique hormonal make up put a huge stress on the body over a short time. The inability to cope with these changes is often the cause of sacroiliac strains and pubic symphysis diastasis.

Unlike regular back pain, pregnant women have the extra consideration of an enlarged uterus whose strong uterosacral and round ligaments attach onto the sacrum and pubis putting extra stress through these structures.  Combined with the production of a hormone relaxin in preparation for the birth, the pelvis ironicallly has to increase its weight-bearing capabilities whilst accommodating for softer supportive ligaments. This makes the pelvic girdle a more relaxed, vulnerable piece of architecture during pregnancy.

Orthodox medicine tends to classify mechanical back and pelvic pain during pregnancy into roughly 3-5 categories according to the location of symptoms; low back pain due to either joint or disc dysfunction, sacroilliac dysfunction either unilaterally or bilaterally, pubic symphysis pain or pain in all 3 pelvic joints.

From an osteopathic perspective all these conditions are variations on a theme, that is, they are all the result of poor accommodation to the increased physical demands put on the body during pregnancy. Symptoms are likely to occur at the weakest most vulnerable joint in the kinetic chain. The job of the osteopath is to assess the patient and make a structural osteopathic analysis or "diagnosis" to determine why the body is not adapting well to the changes. Furthermore, the osteopath must decide which structures are central to treatment in order for the  body to adjust adequately and compensate during the transition.

Osteopathy does not encourage a protocol treatment and needless to say the osteopath should routinely check and treat each joint in the body, however, there are central structures that require extra attention. The sacrum, hips and perineum are the closest associated structures to the joints of the pelvis and they are expected to accommodate. Any excess tightness in any of these joints reduces their ability to absorb forces and strains the sacroiliac and pelvic joints.

The sacrum for example needs to nutate and counter-nutate (flex and extend) according to the movement of the spinal vertebrae superior to it. If the sacrum is unable to rock back and forth and twist on its vertical axis the illiolumber and pubic symphysis will be strained.  Similarly, any tightness in the hip adductors, external or internal hip rotators mean the femur and ischium tend to function as one unit. Movement of the leg results in traction and stress of the pubic symphysis.

The muscles must also be considered. Any tightness in psoas, abdominal muscles, lumber erector spinae, diaphragm and quadratus lumborum will result in further spinal and pelvic instability.

The osteopath must have an coordinated treatment approach directed at the hips, sacroiliac joints, spinal curves, lumber and abdominal muscles and uterine ligaments in order to treat the pregnant woman affectingly. If the osteopath manages to integrate these structures into a treatment plan the patient is likely to benefit in the long run from a thorough assessment that addresses the root of the problem.


Danny Sher qualified from the British School of Osteopathy (1996) and practices in Jerusalem and Modiin.
Www.osteopath.co.il