Monday 27 December 2010

What is the aim of core stability?



The aim of core stability training is to learn how to effectively recruit the deep trunk musculature and then to control the position of the lumbar spine during dynamic movements (like a squat).


TVA

Lumbar multifidus

Internal oblique

Pelvic floor

Diaphragm

Medial fibres of QL


The co-contraction of all these babies produces stability via two main mechanisms:


1) Force production via thoracolumbar fascia (TLF) creating tension and stability posteriorly

2) Increasing intra-abdominal pressure (IAP) stabilising the spine


The TLF can provide tensile support to the lumbar spine via deep trunk muscle activity. The TVA and internal oblique both attach to the thoracolumbar fascia which wraps around the spine connecting the deep trunk muscles to it.


When the TVA contracts it creates an increase in tension in the TLF which in turn, transmits a compressive force to the lumbar spine which enhances stability.


The increased tension of the TLF compresses the erector spinae and multifidus muscles, which encourages these to contract and resist spine flexion forces (Lewis et al, 2000)


The IAP mechanism can provide a supportive effect to the lumbar region as the co-contraction of the pelvic floor, diaphragm, TVA and multifidus increase IAP. This results in a tensile force being exerted on the rectus sheath (rectus abdominus) which adds to this effect.


The 'supported bag of air' effect reduces compression and shear forces acting on the spine. Research shows that IAP increases before and during lifting heavy objects e.g. weightlifting.

Saturday 11 December 2010

Vertebro basiliar insufficiency symptoms

Dizziness
Drop attacks
Diplopia
Dysphagia
Dysarthria

Nystagmus
Nausea

Shift of the mediastinum

In a couple of the CRAM case studies for my exam there are reports from a CXR of a shift of the mediastinum to either left or right.

I've now found out what the most common cause for this is, pneumothorax (collection of air in the pleural cavity). However there are different types of pneumothorax and each one causes a shift in a different direction. Here's why...

TENSION PNEUMOTHORAX

Usually occurs as a result of trauma (e.g. a stab wound) and results in an accumulation of air under pressure in the pleural cavity. The wound (or opening) acts as a 'one way valve' allowing air in to the thorax but not out.

In this case the mediastinum would shift AWAY from that area (e.g. if it was a left lung tension pneumothorax the mediastinum would shift to the right). This is due to pressure gradients and the fact that it's encourage to move from an area of high pressure to low pressure.

SPONTANEOUS PNEUMOTHORAX

PSP (primary) refers to those without chronic lung conditions
Secondary refers to those with underlying lung disease

In this case the lung would collapse but there's no 'one way valve' effect letting air in and not out. Therefore the pressure on the side of the collapse is lower than the contralateral side...meaning that the mediastinum shifts TOWARDS the collapsed lung!

Saturday 4 December 2010

Meninges - Membranes surrounding the brain and spinal cord

Dura Mater - Outermost layer

Tough, inflexible and 'leather like'.

Lines the inside of the skull where it's attached to the bones.


Arachnoid mater - Middle layer (separated from the pia mater by the subarachnoid space)

Delicate spider-web like structure

Attached to the inside of the dura

Surrounds the inside of the brain and spinal cord
(aracnoidea encephali & spinalis)


Pia mater - Delicate innermost layer

Thin / mesh like

Closely envelops entire surface of brain

Runs down fissures of the cortex

Supplies brain tissue with blood vessels



Subarachnoid space - Between arachnoid mater and pia mater is the CSF which absorbs and disperses excessive mechanical forces that might otherwise cause serious injury. It's produced by the choroid plexuses in the lateral ventricles and drains into the dural venous sinus into the internal jugular vein.

Slump Test


1) Patient sits with thighs fully supported on plinth / hands clased behind their back


2) Patient is instructed to slump shoulders towards groin


3) Physio applies gentle over pressure to this trunk flexion


4) Patient adds cervical flexion / maintained by therapist


5) Patient performs unilateral knee extension / active dorsiflexion


6) Patient is instructed to extend neck. If cervical extension causes a decrease in symptoms this is a +ve finding indicating ABNORMAL NEURODYNAMICS