Orthopaedic Future- 1 (AR in Orthopaedics)

Introduction:

With the dramatic launch of Apple Vision Pro last week and the mixed response /reception regarding its cost, it is undeniable that AR/VR glasses are here to stay.

All major players are in this market (Microsoft Hololens, Meta’s Oculus Quest and google planning their version too) and the future seems promising. ?

What makes the premise particularly enticing is the ability to augment reality by placing/superimposing virtual objects onto real life objects and taking imagination to the next level!

Wouldn’t it be amazing to super-impose a CT scan or an MRI scan on a real life patient in the operating room to enhance surgery, localise the lesion better, get a 3 dimensional geometric view through a small incision?

What is Augmented reality??

“Augmented Reality (AR) refers to a technology that superimposes computer-generated elements, such as images, videos, or 3D models, onto the real world in real-time. It enhances a user's perception and interaction with their environment by overlaying digital information onto their view of the physical world”……... Chat GPT answer!

The term AR was coined by two Boeing engineers who developed a simple see-through headsets that allowed engineers to perform complex wiring mechanics. AR has subsequently evolved with high definition head mounted displays, powerful hardware and software and is literally pervading into all fields including healthcare. There are currently two main delivery systems for AR. The head mounted displays (HMD) or the hand held devices such as smartphones.

The advent of Apple Vision pro has put the focus on HMDs. These can be standalone devices with powerful hardware in built into the frame or be connected with external hardware. While most commercial uses of AR currently focus on the entertainment and gaming industry, AR is already permeated into the shopping industry where you can ‘try before you buy’ spectacles, dresses or furniture.

Without going into too much details, an AR device needs to track and sense objects and movement in the external environment and superimpose virtual objects onto these in a way that they appear real. It can do this by outside-in tracking (cameras and sensors are in the room and relay information to the headset), inside out tracking (cameras and sensors are on the device) and a technology called simultaneous localisation and mapping (SLAM) which picks up feature points, plane finding, anchors and light estimation from the environment.

?AR in Orthopaedics:

There are a number of pre-clinical studies documenting the use of AR in orthopaedics.

Wang et al perfomed percutaneous Sacro-iliac screw insertions within 5 mm accuracy using AR augmented navigation systems.

Another good use of AR is the insertion of distal locking screw using Microsoft Hololens AR2 completely eliminating the need for Xrays and shortening surgical times significantly.

Complex osteotomies would be another good area to explore the use of AR. Kiarostami et al performed a proof of concept study for use of AR in performing a complex Ganz periacetabular osteotomy with increased precision and reduced surgical times on a saw bone model.

Placement of pedicle screws can be made easier with the use of AR too and localisation of osteoid osteoma without the need for an intra-operative CT scan.

Concluding remarks:

Will the commercial availability of AR headsets make these a common occurrence in the operating room?

Will you join the AR revolution?