Section 6.4 – Lateral mobilisation of the mesosigmoid and left mesocolon

Left sided mobilisation of the mesentery begins by retracting the mesosigmoid medially

This exposes congenital adhesions that can be divided

These are highly variable but always present

They should not be mistaken with regions of the reflection

With which they can fuse

Their division exposes the reflection

When the reflection is divided through

The undersurface of the mesosigmoid is apparent

The mesosigmoid is detached,

But maintained fully intact at all points

The mesosigmoid is continuous with the left mesocolon

Once the mesosigmoid has been detached,

The in continuity left mesocolon becomes apparent

This is also detached, in the same manner, from the underlying fascia

This way, it is maintained intact, during the detachment process

The key to detachment of an intact mesentery

Is to identify the zone (or plane) between mesentery above and fascia below

This plane is always present, and is the roadmap used in surgical dissection

The plane is demonstrated, by lifting the mesentery away from the fascia

Thereby placing the interface between fascia and mesentery under stretch

Separation of the mesentery from fascia, is called mesofascial separation

It can be achieved by sharp or blunt dissection

But always requires a clear field of view

And unimpeded access

With continued mesofascial separation, the undersurface of the mesosigmoid becomes apparent