T6

backpain

In this world of brain plasticity and the excitement it engenders we may sometimes forget the complexities of the rest of body and maybe also, the rest of the nervous system.

The T6 area in the clinic
What is it about the T6ish area? The middle of the back is a very popular place to experience pain and tightness. About 30 years ago, as the neurodynamics thinking emerged, I was intrigued with this area. A repeated clinical pattern exists where many people with positive straight leg raises (SLR) or slump tests often complain of pain around the T6 area. Additionally, if someone had a positive SLR or passive neck flexion, suggesting some alteration of meningeal biomechanics, palpation around the T6 area often revealed tenderness and stiffness, usually unbeknown to the owner of the back. People, post whiplash, often have this finding and indeed whiplash sufferers who complain of pain in the mid thorax may have a worse prognosis (Maimaris, Barnes et al. 1988). Many clinicians reading this blog are well aware that if you gave the mid thorax a bit of a wriggle and shake, the whole body movement can improve and SLR and slump test findings will often improve, sometimes markedly.

SNS_ebook_pg120

The science
Intriguingly, some science on neuromeningeal biomechanics emerged at the time of developing neurodynamic theories. With an extrapolation from a 24 human cadaver study by Louis (1981), supported by earlier work by Breig (1978) and painstaking monkey dissections by Smith (1956), the year I was born! I came up with the image below from “Mobilisation of the Nervous System (1991). The spinal canal could be around 9 centimetres longer in flexion than extension – somehow the contained cord and meninges have to adapt. Check out the T6 area – it doesn’t move that much in relation to the surrounding canal – kind of like if you pull a piece of elastic from both ends, there is a bit in the middle that doesn’t move much in relation to its surrounds.

If there was something special about the area then you would expect that the anatomy would express something about the function. While there has been minimal study (and few would bother today), the major blood vessel for the thoracic cord and meninges comes in just under T6 – so it’s probably not a good place to have a lot of sliding around, and in addition, the canal here is quite narrow and the dura mater is thicker than anywhere else along the neuraxis. Maybe it is designed to be like the middle of a piece of elastic?

T6 today
Pause a moment and marvel– the spinal cord in the thorax may only be a little over a centimetre in diameter with the surrounding canal maybe around 1.4 centimetres and also containing meninges and cerebrospinal fluid (CSF) whose freshness is necessary for cord nutrition. This tiny area has a lot of work to do in representing the low back, pelvis and legs. I think it is best to add the cord into modern concepts of representation and neuromatrix which are often all brain based.

I think that no matter what, if central sensitisation is considered, then the physical health of the nervous system including the cord should be entertained. Is the T6 area a place that is perhaps biomechanically more at risk than other parts of the nervous system especially when you consider what humans do with their bodies these days? Physical problems with physiological consequences could result in significant nociception from the meninges, peripheral neurogenic contributions from sinuvertebral nerves innervating the meninges, and nerve roots plus mechanically induced contributions to sensitisation. The slump test, especially in long sitting may be useful to check it out and I am sure the area loves inputs such as yoga, dance, martial arts and just a good old roll around on the floor.
In conclusion, there is a place in the biopsychosocial framework for T6.

Tell us your T6 stories

Breig, A. (1978). Adverse Mechanical Tension in the Central Nervous System. Stockholm, Almqvist and Wiksell.
– Louis, R. (1981). “Vertebroradicular and vertebromedullar dynamics.” Anatomia Clinica 3: 1-11.
– Maimaris, C., M. R. Barnes, et al. (1988). “‘Whiplash injuries’ of the neck: a retrospective study.” Injury 19: 393-396.
– Smith, C. G. (1956). “Changes in length and position of the segments of the spinal cord with changes in posture in the monkey.” Radiology 66: 259-265.

David Butler, Noigroup

Upcoming NOI courses

Australia
Melbourne April 11-12 Mobilisation of the Nervous System [FULL] Michel Coppieters
Sydney May 9-10 Explain Pain [FULL] D. Butler + L. Moseley
Perth June 14-15 Explain Pain David Butler
Perth June 20-21 Pain, Plasticity & Rehabilitation Brendon Haslam &David Butler
Canada
Winkler MA April 26-27 Mobilisation of the Nervous System Sam Steinfeld
Fredericton NB August 18 Mobilisation of the Nervous System Sam Steinfeld
Montreal Sept 18-19 Explain Pain Sam Steinfeld
Europe
Zurzach CH April 25-27 Mobilisation of the Nervous System Hugo Stam
Hamburg DE April 25-17 Mobilisation des Nervensystems Irene Wicki
Århus DK May 3-4 Mobilisation of the Nervous System Tim Beames
Ljubljana SI May 9-10 Graded Motor Imagery Tim Beames
Freiburg DE May 9-11 Mobilisation of the Nervous System Irene Wicki
Bad Zurzach CH May 9-11 Der “Problematische” Schmerzpatient Martina Egan-Moog
Saarbruecken DE May 16-17 Schmerzen Verstehen Martina Egan-Moog
Rheinfelden CH May 16-18 Mobilisation des Nervensystems Irene Wicki
Winterthur CH May 24-26 Mobilisation of the Nervous System Irene Wicki
Athens GR May 24-25 Explain Pain Tim Beames
Winterthur CH June 30 July-1 Graded Motor Imagery Hannu Luomajoki
UK/IE
Dublin June 7-8 Mobilisation of the Nervous System Tim Beames
London UK May 30-31 Graded Motor Imagery Tim Beames
Dublin IE June 7-8 Mobilisation of the Nervous System Tim Beames
Oxford UK June 21-22 Mobilisation of the Nervous System Ben Davies
Bournemouth UK June 21-22 Mobilisation of the Nervous System Tim Beames
Derby UK June 25-26 Explain Pain Ben Davies
London UK July 12-13 Explain Pain Tim Beames
London UK July 15-16 Mobilisation of the Nervous System Tim Beames
Derby UK July 17-18 Mobilisation of the Nervous System Ben Davies
USA
Chicago May 10-11 Graded Motor Imagery Robert Johnson
Los Angeles May 17-18 Explain Pain Steve Schmidt
Los Angeles May 19-20 Clinical Applications: Lower Limb Robert Johnson
Philadelphia, PA August 9-10 Explain Pain Morten Høgh
Chile, US Sept 7-8 Mobilisation of the Nervous System Robert Johnson
Advertisements

2 Responses to “T6”

  1. nccspine Says:

    G’day David,

    I agree the mid Thoracic region is certainly an area that brings many subtle complexities.

    There is the T4 Syndrome that Maitland described in the 1950s. Here painful symptoms were thought to be caused by a sympathetic nervous system reaction to hypomobile thoracic segments. Czech rehab specialists from the Prague School of Rehabilitation (Mojzisova and more recently Kolar) relate mid back and rib dysfunction to a host of musculo-skeletal as well as visceral health issues. Then there is the Swiss Rehab specialist Brugger who used thoracic ‘springing’ as one of the ‘monitors’ to measure response to manual care applied to different regions of the body.

    My own interest in the area developed when I was looking for ways to relieve the postural aches and pains in cyclists. I eventually created a simple device called a PosturePole to help address Forward Head Posture, and this has proven to be popular in many clinics. While I expected to relieve tight muscles, what most people talk about and appreciate is a ‘relaxation response’ effect and a shift to abdominal breathing. Out of curiosity I measured Heart Rate Variability (HRV) in a small number of subjects and noticed a distinct shift in their HRV patterns similar to that seen in meditation.

    I freely acknowledge that I have not published anything and that I have a vested interest, but there seems to be a lot going on in that area that goes beyond simple muscle aches and pains.

    Regards

    Bruce Scott

  2. Julie Ermoloff Says:

    T6 as the driver of lower C-spine discomfort

    I’m a 3rd year Doctor of Physical Therapy student at Northwestern University in Chicago, USA and will be graduating this year…It goes without saying how very excited I am to begin my career as a physical therapist after 3 long, wonderful, terrible, enlightening, arduous, mind-blowing, up-n-down, super years at Northwestern. As our professors (soon to be peers) have forever informed us…”learning is a life-long process”.

    Your blog post – ‘T6’ – cultivated a next level of excitement for me on a number of levels: 1) we’ve learned an awful lot about the biopsychosocial model and the importance of integrating all three prongs so as to help facilitate an appreciation of all bio-psycho-social features, such as potential pathologies, pain mechanisms, physical impairments, psychological responses, personal factors, poor coping, anxiety, depression, catastrophization, work and occupational factors, compensation, etc, in the assessment and management of our patients; 2) we’ve learned about the thoracic spine and the links between the T-spine and C-spine functioning; 3) the personal challenges I have with thinking through patient cases where the primary complaint is from the neck; and finally, 4) the similarities between your informed post and the signs/symptoms of a 1st year DPT student…let’s call him ‘Bobby’. Bobby had requested I, along with the guidance of my professor, James Elliott, PT, PhD have a look at his neck…

    Bobby’s clinical presentation was, quite frankly, not all that impressive from a standard musculoskeletal complaint…at least to me. This had me scratching my head, considering the nature of his injury just 2.5 years ago: a C7 spinal fracture from slamming his head into the boards during an ice hockey game in 2012. The event, recalled Bobby, produced an immediate electric sensation to all ten fingers and ten toes. He reports no loss of consciousness, but a feeling of fear/dread that he may have injured his spinal cord. Bobby remembers lying still on the ice for a few moments; he was immobilized and transported to hospital where imaging confirmed the C7 vertebral fracture with no cord damage.

    Today, his primary complaints are neck (cervico-thoracic region) stiffness & discomfort 5-6/10 with prolonged positioning, especially with prolonged sitting (welcome to student life, Bobby). Pain, remarkably to me, is minimal (1-2/10 with end-range extension), no complaints of radiating symptoms into BUE/LE. Bobby states he can temporarily alleviate his neck discomfort with right and left neck side- bending that typically results in a ‘pop & crack’.

    Notable objective findings include posterior pelvic tilt, slight thoracic kyphosis, B protracted shoulders; normal C-spine AROM; pain w/ overpressure into lower C-spine extension; positive Slump test; good endurance of deep neck extensors; normal and equal muscle length bilaterally of UT, lev scap, SCM, scalenes.

    Cervical segmental exam w/ cervical flexion was unremarkable. Interestingly, central and unilat P→A PPAVMs at lower C-spine were hypomobile and somewhat painful…but discordant to his daily symptoms. The patient had not mentioned any thoracic pain/symptoms until I initiated PPAVMs at the mid-thoracic spine; at which point he mentioned feeling stiff in this area, which he believed was due to his consistent UE strength training. Long of the short, I was able to reproduce his concordant lower cervical discomfort when performing a PPAVM on the spinous processes of T4, T5, but most notably at T6…

    Bobby’s case is fascinating to me as the findings from my initial examination were overall unremarkable and my initial thoughts were confident that this was most likely a facet issue in the lower C-spine with referral to the mid-T-spine. However, it was not until digging deeper (or more caudal to the area of ‘pain’ & discomfort) that the potential contributor to ongoing concordant symptomatology was revealed.

    The thoracic spine, in this case, T6, can be hypothesized to play a role in lower C-spine discomfort due to the interdependence of the kinetic chain and postural compensations at the lower C-spine as a result of mid-thoracic spine dysfunction. It would be interesting to follow up with Bobby to determine the effects of mobilizing the thoracic spine and the impact of postural retraining on the patient’s level of lower C-spine discomfort, as we know there is evidence for such an approach. I remain humbled by the body’s plasticity (brain, spinal cord, muscle, etc), my education, and the professional paths that lie ahead for me and my peers.

    In conclusion, I can’t wait to graduate and I want to thank you for reminding me to never forget T6 (and to never stop learning).

    Cheers,

    Julie Ermoloff
    Northwestern University
    Feinberg School of Medicine
    Department of Physical Therapy and Human Movement Sciences
    Class of 2014

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: