- Spinal degenerative problems
- Thoracic and lumbar disc problems
- Spinal stenosis
- Neurogenic claudication
- Neuro-Oncology - Brain and Spinal Tumours
- Society of British Neurological Surgeons (SBNS)
- British Neurooncology Society (BNOS)
- British Association of Spinal Surgeons (BASS)
- FRCS (Eng) Representative on Joint Colleges Exam Board for neurosurgery exit exam FRCS(SN)
- National and International Examiner for Part 3 FRCS(SN) Neurosurgery Exam
- Sports Medicine Section member of the Royal Society of Medicine
Mr Critchley is the lead for Spinal surgery at Brighton and Sussex University Hospitals NHS Trust from 2014-2016 and 2019- date. He was the lead for neurosurgery from 2016-2020 and became a consultant in Brighton and Sussex in 2001.
He also was the co-host of the British Association of Spinal Surgeons (BASS) meeting in Brighton in 2019.
His interests are in General Adult Neurosurgery and Spinal Surgery, including degenerative spinal surgery, complex spinal surgery, tumour surgery, cranial and spinal, neurotrauma and neurovascular disorders.