By: 16 December 2019
Robots in surgery: Essential technology or expensive toys?

In this issue of OPN, Peter Ogrodnik discusses the rise of robots in industry and invites readers to take part in a Christmas Quiz during the holiday season

Before we even discuss robots in surgery we should consider the robot itself. In industry, engineers, accountants, site managers and warehouse staff see robots in a different light to that pervasive in medicine. The term robot was defined in standards in the 1930s: the beloved Meccano magazine [1] took this and produced a design for a robot for stacking blocks. The first industrial robot to go into production was by Unimate [2] in the late 1950s/early 1960s, and the PUMA [3] (Programmable Universal Machine for Automation) is still going strong today (Figure 1).

The historical aim of robot development has been to take over from humans in repetitive situations where a lack of accuracy, concentration, or deftness could lead to errors being made. One example, the repetitive insertion of wheel retention bolts on an automotive assembly line, illustrates potential human errors. Missing bolts, or not tightening a bolt to the right setting can be commonplace. Robot-based assembly lines avoid these issues by avoiding human error.

In electronics, pick-and-place robotic devices have been assembling circuit boards since the 1980s and it is highly likely that the computer on which this has been typed has been robot assembled. Indeed, you can buy a simple pick-and-place robot for less than $90, which can be very sophisticated (Figure 2) with inbuilt vision systems to detect a defect component or select specific items. People often forget that robots are great at holding things in the right position.

Equally, robots are used in settings that would be deemed hazardous to human life. Automotive paint spraying lines and in the heart of nuclear power stations are good examples. However, in industry, mixing robots with people is not seen as a good thing to do: there is a great deal of health and safety guidance to follow to ensure that the frail human body is not damaged, Pityocamptes like.

The use of robots in industry has grown. In 2016 there were 75 robots per 100,000 [4] employees (in Europe this was 99 per 100,000): dominated by the automotive sector. But in all cases, the robots have been developed and adapted in order to replace humans, to increase productivity, increase efficiency, or to remove humans from hazardous environments.

The clinical world has not followed suit, but there could be valid reasons.

Modern use of the term robot has been expanded in common parlance, to include remote control devices. One only has to watch Robot Wars to realise this. Robots are remote controlled devices but, unlike Robot Wars, the human controller is replaced with a computer.  Early robots simply “copied” human action through very simplistic machine learning techniques. Modern robots are slightly more sophisticated but, in the end, they still “mimic” some form of existing action or methodology.

It is for this reason, I propose, highly accurate remote-controlled devices have dominated the use of robots in surgery. These devices have the sole aim of extending the working range of the human being by enabling actions at the sub-millimetre level while maintaining accuracy at the multiple millimetre level. At the sub-millimetre level, the need for accuracy and steadiness is obvious, but at the larger scale one may wonder why. If a cut is to be straight, then a robotic arm will produce a straight cut where hand-held techniques produce a nearly straight cut. In other words these devices have removed the inherent fallibility of the human hand. However, I struggle to call these robots.

Knee implant surgery has examples of robotic systems that look like robots seen on a factory floor. Often these are very expensive devices, far in excess of their shop-floor counterpart. Institutions, such as Imperial College, have designed their own systems; and these have reached the market place. Yet even with this prestigious start, their use is not widespread. At meetings, surgeons still discuss the pros and cons of such systems. They often find it hard to justify the additional cost against any significant improvement in outcomes. I suggest this is because the starting premise was too complex; the technology needed to be accepted first.

If we return to the start, robots were developed to replace humans where the work was repetitive and “copyable”. Even automated aircraft landing systems follow this basic premise. So why did orthopaedics investigate such a complex procedure such as the hip or knee implant? Why did it not go back to a basic question: a simple application that can be used to prove the point? Maybe this would have led to a more widespread use of robots in surgery.

In trauma this is best exemplified by the drilled hole. Many screws are in positions where drilling through the bone could result in the drill’s path causing complications due to penetration or collateral damage (pelvic fractures spring to mind [5]). Could a robot not do this so that the drill did not protrude from the bone by more than a certain amount? Could a robot not guarantee the path? I have seen this in action in the laboratory, but have yet to see it in theatre.

Many implants, used for the treatment of fractures, have holes that require accurate location but which are within the bone itself and, hence, invisible. These holes are often located with the c-arm and then aligned with the drill using said c-arm. Not only is there a risk of missing the hole but also an additional risk of exposure to the surgeon (as their hands are in the x-ray field). Would a robotic solution make this procedure more successful, and remove the surgeon from a harmful environment? I have been working on this for some years, and I can say the robotic solution has worked (first-time, every-time) with both skilled and unskilled users.

Many devices have repetitive and / or optimised hole positions. Rather than relying on a drill guide, with all the issues that inherently follow, why could a robotic solution not be used?

Therefore, I put it to you that robots in surgery have not been adopted in the numbers associated with the automotive, nuclear, electronics, and aerospace industries because of the applications selected. I leave you with a Christmas Quiz to ponder over the Port. If you could pick one orthopaedic procedure or process that fits the use of robots (as described above) better, what procedure would it be?

I have set up an online survey for you to submit your answers. I will review them in the next issue.

Link to Survey: 
https://forms.gle/ZtsmuSPDMtVoVjMV8

References:

  1. Meccano (1938) An Automatic Block-Setting Crane. Meccano Magazine. Liverpool UK: Meccano. 23 (3): 172.
  2. Moravec, P (2019), Robot, Encyclopaedia Brittanica.
  3. Cyberbotics, WebBots User Guide: Unimation’s Puma 560, https://cyberbotics.com/doc/guide/puma
  4. Cakan, A & Botsali, F (2016), Inverse Kinematics of a PUMA Robot Using MSC ADAMS.
  5. Martinelli,V (2019), How Robots Autonomously See, Grasp and Pick. The Robot Report,
  6. Crowe, S (2018), “10 Most Automated Countries in the World”, The Robot Report,
  7. Matta, J.M. and Tornetta III, P., (1996). Internal fixation of unstable pelvic ring injuries. Clinical Orthopaedics and Related Research, 329, pp.129-140

Professor Peter Ogrodnik leads the MSc in Medical Engineering Design at Keele University. The opinions stated do not necessarily reflect those of Keele, its staff or its students.