**1. Introduction**

The bone drilling process is a basic manipulation in the osteosynthesis of the bone fractures. Osteosynthesis is a surgical procedure, which stabilizes and joins the ends of fractured (broken) bones by mechanical devices such as metal plates, screws, pins, rods, wires. Nowadays by statistics every year about one million people in Europe need such an operation where implants into bones are inserted.

The process of bone drilling is characterized by a number of input and output parameters. The input parameters define the conditions under which the process occurs, while the output parameters determine the outcome of the process.

The input parameters as feed rate [mm/s] and drill speed [rpm] are of the greatest importance for the final result of the drilling process: thermal and mechanical damages of the bone tissue, hole quality, second cortex breakthrough detection and penetration depth in the case of bicortical bone drilling.

A large amount of researches have been published related to the influence of these parameters on the bone drilling process. Only publications, indexed in

#### *Latest Developments in Medical Robotics Systems*

SCOPUS, related to the bone drilling process, are above 3000 since 2000 [1], which proves the importance and relevance of researches in this area.

Most of the drilling operations in orthopedic surgery are done manually (nonautomatically) by hand drills and drilling performance depends on the surgeon's manual skills and 'drilling by feeling' [2]. That means recognizing the breakthrough detection (identification of the moment of time when the drill bit exits the second cortex), working with drilling rate good enough not to cause any damages to the bone or soft tissues closed to it [3].

The influence of the subjective factor is a prerequisite for the emergence of a number of problems in manual drilling. The most significant ones are:


Osteonecrosis is a kind of the health status depending on various conditions which lead to bone death [4]. The result is loss of blood supply or death of bone cells. It can be classified as vascular, infective, drugs or toxins, inflammatory, congenital, autoimmune, traumatic and endocrine or metabolic. One specific kind of traumatic osteonecrosis is thermal necrosis of bone.

The question of subjective factor reduction has its answer – automatic bone drilling. The use of robots would have a significant role for eliminating or minimizing the human error.

Robot applications possibility increase in the orthopedic surgery since 2000 [5, 6] but still they are rare in usage for the sake of their high cost. For example, ROBODOC (Curexo Technology Corp.) is applied for hip joint arthroplasty and costs 600 000 \$ while RIO (MAKO Surgical Corp.) - 1 000 000 \$ [7]. Nevertheless, the operation costs in social aspect decrease: patient recovery period is less than conventional one; complexity of the surgeon's manipulations and the risk of his potential errors become smaller [8]. On the other hand, the robot application in surgery requires specific maintenance and training of the medical staff aiming to guarantee the patient safety.

The first efforts for robot application in the orthopedic surgery are based on the industrial manipulating systems. The advanced tendency is oriented to a design of manipulative systems according to the specifics of concrete orthopedic manipulations aiming maximally simplification of robot mechanics [9, 10].

Thus so called Handheld Robotized Systems appear [11]. The handheld robotized systems answer entirely or partially to the definitions of robot [12] and robotic surgery nowadays has accepted the definition [13] of the Society of American Gastrointestinal and Endoscopic Surgeons and Minimally Invasive Robotic Association (SAGES–MIRA) Robotic Consensus Group.

The purpose of handheld robotized systems development is to reach the accuracy and precise working of the stationary multifunctional robots. Currently the following devices are available on the market and in the orthopedic surgery practice:

#### • handheld robotic device **SMARTdrillR**

It is developed by US Company SMD Inc. (Smart Medical Devices) and first time is presented in 2017. It measures the hole depth in real time and eliminates the plunge after the far cortex [14, 15]. SMARTdrillR has two motors: for rotation and for linear translation of the drill bit along the drilling direction. The data transfer

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*Orthopedic Bone Drilling Robot ODRO: Basic Characteristics and Areas of Applications*

error. The overheating problem prevention is not commented.

between the SMARTdrillR and its control system is wireless. The drill bit and bone position are shown by LED indicator. The thrust force is not under control but it is only limited by the harp motion. The speed is set preliminary. The decision to stop drilling is taken by the surgeon. The experimental data are obtained for specimen simulating the bi-cortical bone features. They are reported when made under ideal conditions - simulated specimen with constant density (not bone) and flat surface of walls. The stop decision for drilling is manual (not automatic). The surgeon's decision is taken according to the data on the display which may cause a subjective

It is developed by "McGinley Orthopedic Innovations", US [16] and has two working regimes: conventional (Free Hand Mode) and bi-cortical. In bi-cortical regime the surgeon receives the signals from the device when the drill bit is close to the end of far cortex. This helps to him to stop drilling on time avoiding undesirable penetration in the soft tissues. The surgeon controls the thrust force himself all the time. No information is given for the criterion to stop rotation after the breakthrough and for penetration of the drill bit after the far cortex end. This system is not a robot according to the accepted definitions but allows receiving information for already drilled depth and far cortex end in real time. Among its disadvantages are no thrust force control, no prevention of overheating, and no automatic detection of breakthrough.

It is still under development. This system is oriented to bi-cortical drilling only and especially for precise breakthrough detection and automatic stop of drilling. The stop decision is based on control algorithm where error of the feed-back position is analyzed during the motion. Constant speed is set in linear motion law and the maximal thrust force which can be applied is restricted. But the drilling time is over 400 s for cow bone bi-cortical drilling as it is reported standing on the experimental results which is very large time in comparison with the surgical practice. That reflects to high temperature in drilling zone (data for the temperature devia-

Many papers and books are written which are devoted to various aspects of robots. Lots of authors of different nationalities have given many arguments trying to confirm their arguments concerning the robot understanding, characteristics and definitions [18]. Nevertheless some variations appear about the attempts to formulate a unified definition - the general point of view includes several main features needed to describe a device or machine as a robot. So, these general common characteristics which an object must have to be really called a robot are as follows:

*DOI: http://dx.doi.org/10.5772/intechopen.96768*

• surgical drill device **IntelliSense**

• handheld robotized system **DRIBON** [17].

tion are not reported) which causes negative results.

**2. Orthopedic bone drilling robot ODRO**

• Mechanical system

• Computer control system

• Driving system

• Sensor system
