Surgical approaches to the brain and spinal cord

Surgical approaches to the brain and spinal cord[edit | edit source]

trepanation or drilling – the smallest approach
- used for punctures (abscesses, cysts), puncture biopsy, evacuation chr. subdural
- in an emergency, it can also be used diagnostically when epidural or acute subdural bleeding is suspected
- a short incision is made on the skin, subcutaneous tissue and periosteum
- drill by hand or with a power drill, the diameter of the hole is usually 10 mm

Trepanated skull, Bronze Age

percutaneous tap – targeted point tap with a diameter of 2.5-3 mm for puncture and drainage of the ventricular system
- also for stereotactic performances
osteoclastic trepanation(craniectomy) – by widening the hole with bone forceps (we will chip it into the surrounding area, ...)
- usually during operations in the infratentorial space
- supratentorial, it is mainly used in traumatology - in acute conditions (epidural or subdural evacuation), comminuted fractures of the calf, ...
- it is fast
osteoplastic trepanation (craniotomy) – the most common method of access to the supratentorial space in planned procedures
- the skin incision has the shape of a horseshoe and a pedicle with a vascular supply, we make holes and cut through the bone between them either – with a' Gigli saw or a craniotome
- the most important thing is not to break the dura, we leave the periosteum on the bone (we fold it open like a book)
- we close the wound by tilting the trepanation plate

Craniotomy, whitish dura mater and arachnoid visible

Gigli's saw used in craniotomy

a necessary consequence of osteoclastic trepanation is a bone defect
this does not matter during operations in the back of the cranial fossa, because it is covered by a thick layer of muscles
on the calf it is a problem (psychological as well - people are afraid of brain injury, ...), they have headaches from frequent fluctuations in pressure, ...
it needs to be solved sooner or later with cranioplasty
bone sources – rib, flat calf graft (from diploe division), tissue bank graft or synthetic material (acrylate resin)

the suture must be waterproof, preferably with an atraumatic continuous suture absorbable material
defects are solved by suturing a graft - fascia lata, periosteum, temporal fascia or even muscle
with leaks, an epidural pseudocyst can develop and there is a risk of meningitis

access from the dorsal side – this is where we operate spinal intradural and epidural processes, lumbar disc herniations, some traumas
- we remove the paravertebral muscles from the protrusions and arches to the minimum necessary extent, pull them away with a spreader
- access can be unilateral or bilateral
- transligamentous approach - via ligg. flava (interarcualia), e.g. for lumbar disc herniation
- partial hemilaminectomy - we will bear next to ligg. still adjacent lat. edges of arches (lateral to proc. transversus)
- foraminotomy – we will remove the bony structures of the dorsal wall of the foramen. intervertebrale (intervert. joint)
- laminectomy – the widest access to the canal, we can bear proc. spinosus with a piece of arcus vertebrae
  - articular processes are preserved
  - for intradural tumor operations, decompression in degenerative canal stenosis, extraction of bone fragments in trauma, etc.
  - if we do not damage the intervertebral joints, the statics of the spine are not significantly disturbed
anterior approach – it is used mostly in the neck area, less often in the chest and lumbar region
- on the cervical spine, this is how we operate on protrusions and osteophytes, extirpation of the meta in the body of the vertebra, in trauma
- access is between the cervical neurovascular bundle (remains laterally) and trachea with esophagus (medially)

BENEŠ, Jiří. Studijní materiály [online]. [cit. 2009]. <http://jirben.wz.cz>.

ZEMAN, Miroslav. Speciální chirurgie. 2. edition. Galén, 2004. 575 pp. ISBN 80-7262-260-9.