ByDr Mehul PancholiResearch AssistantThe City University London

Other Partners:Neurosurgery department, The Royal London Hospital, NHS.Aesculap Inc., B.Braun company, Germany.Emerald Technology Transfer, London, UK.

Medical Device Design

Time & constrains

Funding

Academics

Other stack

Holders

Clinicians

Quality and

Regulation

• Mission, SWOT, Acceptance CriterionStrategic Target

• Observation, Literature, Stake holder Recognition of Problem and Observation

• Diseases, Treatments, StakeholderNeed Screening

• With team members and stakeholdersIdea and Brainstorming

• IP, Regulatory, Business, PrototypingConcept Screening and Selection

• IP, R&D, Regulatory, Quality etc strategyDevelopment Strategy

• Business Model, Funding, LicensingIntegrating Design, Development and Business

Review

Medical Device

User Needs

Design Input

Design Process

Design Output

Validation

Verification

Design and development of intelligent artificial spinal disk prosthesis to measure the comprehensive in vivo

loading on the lumbar spinal disk

To measure the in vivo loading on the lumbar spinal disk

Spine is the most complicated Neuro-Musculo-Skeletal joint (or series of joints) of the body

Related diseases: Disk degenerative diseases

Mechanical loading and Disk Degenerative Diseases have positive strong relationship

Surgical treatment options: Motion preservation (TDR) and fusion

Economical Back Pain Impact: In the UK, the National Health Service (NHS) spends £512 million on hospital costs, £141 million on GP consultation and £150.6 million on physiotherapy treatment. The total spending is more than £1 billion per year

Sensors on spinal

instruments

Sensors on vertebrae or

disk

Sensors on spinal disk

prosthesis

Sensors

Loading

Spinal disk prosthesis

Vertebra

Comparative stress analysis test: Axial compression load rating test (First using FEA software and then actual) using MES – Limit load analysis

Liner static stress analysis for axial fatigue test using MES – Plastic collapse analysis -3KN for 5 Million cycles – Lower max stress value longest fatigue life

Linear static stress analysis for torsion fatigue test – surface forces totalling 200N in bending direction – linear elastic FEA – Lower the alternating stress range longer fatigue life

Disc Wear

Inlay

Deformation

Plate/Inlay

Fracture

Implant-Bone

Interface

unphysiologic

al Kinematics

4h: -300N, static conditioning

16h: -300N/-1000N, 1Hz, sinusoidal

8h: -300N, static relaxation

load steps -1000N, -2000N, -3000N

10° angulation

Test condition + 37°C in water

External displacement sensor sensitivity ±1µm