Robotics and Orthopaedic Surgery: Will Robots Replace the Orthopaedic Surgeon?

Author: Paul Taylor - Consultant

The medical industry has witnessed a dramatic explosion of technological advances and developments associated with robotic and computer assisted surgery. These advances have been made possible not only by advances in computing and engineering technology but also the need to reduce costs, improve clinical outcomes, and improve the efficiency of health care delivery.

These advances have emanated from the pioneering efforts in the development of robotic-assisted surgery as a result of the joint collaboration in the United States between the National Aeronautics and Space Administration (NASA), the Jet Propulsion Laboratory and private interests. Since then a variety of new and novel robotic systems have emerged with indications for a wide variety of surgical applications.

Types of Robotic Systems

HBS Consulting has essentially identified five broad (sometimes-overlapping) types of robotic systems with the potential for surgical application. These are:

· Intern replacements (e.g. limb positioning, retraction and laparoscopic/endoscopic camera holding).
· Telesurgical systems (e.g. access to hard-to-reach areas, access without tremor, surgery on patients remote from the surgeon).
· Navigational aids; Passive manipulator arms that keep track of tools (e.g. unpowered 3-dimensional localising devices). These are basically imaging/localising devices.
· Precise positioning systems; Powered robots that are moved to a location, locked off and power removed, i.e. the robot is used passively. (e.g. tool guide positioning, precise delivery of interventions). These systems require pre-operative planning systems.
· Precise path systems; The robot is used in actively, interacting with patients. (e.g. precise machining of bone, laser resection), pre-operative planning is required.

Some of the better known precise path systems used in orthopaedic surgery include the ACROBOT, ROBODOC, CASPAR (Computer Assisted Surgery: Planning and Robotics) and the neurosurgical robot the Minerva.

The Minerva was one of the earliest robotic systems designed for stereotactic brain biopsy using precise needle placement in combination with CT Scanners.

The ACROBOT (Active Constraint Robot) has been and continues to be jointly developed under a LINK project by Armstrong Healthcare, Imperial College, HowMedica Osteonics (Stryker) and the Middlesex Hospital Trust. The system is being designed for use during knee replacement surgery. ACROBOT allows a surgeon to move a cutter through bone but prevents them from either cutting too much bone or moving out of a pre-defined safe region.

Similarly the ROBODOC system was developed clinically by Integrated Surgical Systems (ISS) for total hip replacement procedures from a prototype created at IBM Research. The system has been used in over 1000 cases at a Frankfurt, Germany hospital between 1998 and 2002 and an estimated 8000 cases worldwide. The system consists of three major components: a planning workstation, the robot itself that does the cutting, and the workstation that guide’s and controls the robot. Figure 1 provides a typical schematic of the information flow between the surgeon, the robotic system and the patient when robotic systems such as the ROBODOC are used.

Figure 1 Schematic Representing Robotic System Information Flow

www.geocities.com/netguruprasad/Madhavan_etal_IEEE_Potentials.pdf

CASPAR (Computer Assisted Surgery: Planning and Robotics) is used in orthopaedic surgery for the implantation of uncemented hip stems and the replacement of the anterior cruciate ligament (ACL).

Advantages / Disadvantages

So what can be considered to be the advantages / disadvantages and what are the long-term prospects of robotic and computer assisted surgical systems?

Proponents of robotic and computer assisted surgery clearly identify a number of significant advantages and scenarios where machines can perform better.

Dr Russell Taylor, Director, NSF Engineering Research Center for Computer-Integrated Surgical Systems and Technology, The Johns Hopkins University; Baltimore, for example has cited a number of key advantages including:

· New Treatment Options: The possibility and capability to treat conditions that could not otherwise be treated.
· Quality: The ability to improve the quality of a surgical technique and as a consequence improve results and reduce the need for revision surgery.
· Time and Cost: The possibility of reducing the time taken over surgical procedures and hence reducing operating room costs as demonstrated by cost benefit analyses.
· Less Invasiveness: The ability to reduce the infection risk and recovery times by the constant feedback of data and information during the surgical procedure.
· Safety: The recognition that robotic systems can reduce surgical complications and errors, improving outcomes and hence reduce costs.
· Accuracy or precision: Robotic systems can significantly improve the accuracy of therapy dose pattern delivery and tissue manipulation tasks.

Conversely, opponents of robotic and computer assisted surgery system would highlight the fact that humans have excellent judgement, hand/eye co-ordination, adaptability, and dexterity. Furthermore since humans communicate well, a surgeon can easily tell a human helper what to do whilst a computer takes time to reprogram. Critics have also highlighted the fact that maintaining sterility is a major issue for medical robots. Most of the robot however can usually be draped or covered with a sterile bag, leaving only the instruments or end-actuators to be sterilised.

In addition, developers of robots have a variety of different design criteria specific to the needs of healthcare providers. The safety requirements for medical devices are far more stringent than for standard industrial machines, and robots are no exception. Both rigorous testing and redundancy safeguards are necessary for these applications. Designers need to consider two possibly dangerous failure modes: component failure and the possibility of a robot executing a correct command at the wrong place or time.

Assessing the market – how bright is the future?

HBS Consulting believes that medical science is on the threshold of a revolution in contemporary medicine with robotics taking a leading role in bringing technology ever closer to the surgeon/patient interface. This revolution is likely to be aided by the reduction in the cost of robotic systems as production and competition increases, as clinical results and patient outcomes prove the efficacy and effectiveness of robotic systems and as robots are linked directly to imaging modalities to improve response times. Average selling prices for robotic systems can run to just under $1m, with the US market commanding the highest selling prices. With increasing restraints on hospital and healthcare system budgets one of the key issues concerning the purchase of robotic systems is the means to not only prove product efficacy but also the ability to provide cost benefit analyses demonstrating value for money.

The points raised are just some of the questions which would be highlighted in a market assessment for robotic surgery applications. Based on the concepts raised in the headline article in this Quarterly, HBS Consulting would tackle the market analysis primarily through interviews with orthopaedic surgeons. The role of physician advocacy in driving the market is seen as a critical component and views on current and future penetration rates is best researched through interviewing thought leaders and surgeons who are both for and against widening use of robotic systems in minimally invasive surgery in general, and orthopaedic surgery in particular.

The primary research process not only allows understanding of current installed base but also planned installations. The task is made somewhat easier by the fact that the target interviewees are likely confined to academic and key community hospitals since these institutions constitute the main thrust of marketing team effort from the established robotics system suppliers. Physician interview questionnaires will also be designed to highlight the benefits and disadvantages of using robotic surgical techniques which will provide valuable information for product development purposes. The value of the assessment exercise is therefore not confined purely to an understanding of market numbers but becomes an important part of wider business strategy. Cross referencing current business development and marketing strategies with physician viewpoints becomes critical and serves to either validate or challenge existing market perceptions.

We anticipate that over the next decade significant improvements in basic engineering knowledge and the development of robust, flexible systems through collaborative research projects will significantly increase the number of surgical applications and enable more precise manipulations in smaller spaces and with fewer traumas to the patient.

Although the future of robotic surgery is certain it is however extremely unlikely that in the foreseeable future robots will ever completely replace the surgeon since through his/her expertise and guidance the safe and accurate performance of each operation is assured.