Last quarter Mazor Robotics Ltd stunned Wall Street by posting a 470% sales jump for the June quarter hitting 11.2 million ILS (Israeli Shekel, about one-fourth the U.S. $) for the trailing 90 days, up from just under 2 million ILS for the same period a year earlier. Mazor effectively booked more revenue in the first six months of this year than they did for all of 2011.
That 470% top line growth rate compares very well with the other orthopedic surgical robotic company, MAKO Surgical Corp., which reported sales of $23.7 million, up 27%, for the same June quarter.
What is going on here…is there a march of robots into the spine surgery suite?
The Robot
Mazor’s robot has no arms, articulating joints or force feedback server motors. It has, instead, a frame which attaches to the patient’s spine, a few million lines of software code and a Pepsi can sized 6 degrees-of-freedom robotic guidance system which hovers directly over the prone patient’s back and guides each implant to its exact, precise and unerringly correct location.
Here is the picture of the robotic controller. Source: Mazor Robotics Ltd.
And of one of the 3 frame options. Source: Mazor Robotics Ltd.
The software? That you’ll have to imagine. But featured below is a picture of what it does. That operating room monitor on the left has a virtual 3D environment which is used by the surgeon to create a preoperative blueprint of the ideal surgery for that specific patient. During surgery the software automatically synchronizes two fluoroscopy images with the CT based surgical blueprint (independent of anatomy). With that in place, the controller is able to guide instruments and implants into place to within 1.5 mm accuracy.
Source: Mazor Robotics Ltd.
So, a robot? Mazor’s system—which is branded Renaissance™—is in reality a robotic surgical guidance system specifically designed for spine and neuro surgery.
Israeli Technology
Mazor, which is based in Israel, is part of the now well documented tradition of advanced Israeli engineering technology and talent.
Israel has more engineers and scientists per capita than any other country. Here a sample of the kinds of technologies that have emerged from Israeli engineers:
- A camera the size of a pill which is literally swallowed by the patient. As the camera travels through the digestive tract, it captures images of the bowel unreachable by endoscopes, so physicians can more accurately diagnose diseases.
- The first fully computerized radiation-free diagnostic scanning device for breast cancer.
- Voicemail, SMS, and other cellular services.
- ICQ–AOL Instant Messenger. Developed in 1996 by a team of four young Israelis.
- The first high resolution camera that fits on a single electronic chip for use in cellular phones.
- The world’s first cell phone.
- Microsoft’s Windows XP operating system.
- Internet and network security technology such as Firewall.
- The first and most powerful portable storage device on the market.
And now, a surgical guidance device roughly the size of a can of soda pop.
Mazor Robotics was founded in 2001 by Professor Moshe Shoham, head of the robotics lab at Israel’s famed technical university Technion, and Eli Zehavi, the former Director of engineering at Elscint.
The company’s guiding principal has been to take the best of Israeli engineering talent and create a compact, affordable and unerringly precise surgical guidance device for spine and neuro surgeons. Such a lofty goal has been extraordinarily difficult to achieve but after 10 years, Mazor has the product ready for prime time—as the recent rush of orders clearly indicates.
98% Less Radiation Exposure
As early as 2007, data was emerging that using the Mazor system, then called the SpineAssist, could improve spine surgery for both the surgeon and the patient. As reported in an April 2007 study, 15 surgeons reported that when they used Mazor’s SpineAssist that their radiation exposure fell 98% even though they were performing minimally invasive spine surgery.
For the patient, this earlier version of Mazor’s Renaissance system also improved implant placement precision 2.5 times over freehand placement. The study, which was conducted at the Cleveland Clinic, Texas Back Institute, Johns Hopkins University and UCLA Medical Center tested the use of Mazor’s system for implanting 217 screws using minimally invasive techniques versus conventional techniques. One group of surgeons worked with the guidance of the SpineAssist system, while another group performed the same procedures freehand.
Radiation exposure dosimeters indicated that surgeons operating conventionally were exposed to radiation levels an average of 51 times greater than the surgeons using SpineAssist. At the same time, with SpineAssist’s guidance, placements deviated by an average of only 1.1 mm from surgical plan site. Placements made using freehand techniques deviated an average of 2.8 mm, which is 2.5 times higher than with SpineAssist’s guidance.
More recently, January 2011, another study (Devito, DP, Kaplan, L, Dietl R, Silberstein, et al. Clinical acceptance and accuracy assessment of spinal implants guided with SpineAssist surgical robot: retrospective study. Spine. 2010;35(24):2109-2115. doi:10.1097/BRS.0b013e3181d323ab.) reviewed the use of SpineAssist to position tools and guide 3, 271 pedicle screws in 14 hospitals for 635 cases using intraoperative fluoroscopy and 139 patients using postoperative CT scans.
The investigators in the more recent study reported that SpineAssist’s screw placements were clinically acceptable in 98% of the cases when intraoperatively assessed by fluoroscopic images. Measurements derived from postoperative CT scans demonstrated that 98.3% of the screws fell within the safe zone, where 89.3% were completely within the pedicle and 9% breached the pedicle by up to 2 mm. The remaining 1.4% of the screws breached between 2 and 4 mm, while only 2 screws (0.3%) deviated by more than 4 mm from the pedicle wall. Neurologic deficits were observed in four cases yet, following revisions, no permanent nerve damage was encountered, in contrast to the 0.6% to 5% of permanent neurologic damage reported in the literature.
Comparative Advantage
Renaissance currently costs close to $1 million in the USA, not including disposables, which run about $1, 500 per case. On average, hospitals charge between $40, 000 and $80, 000 for a lumbar spine fusion surgery. So one Renaissance costs about as much as 15 or 20 lumbar fusion surgeries.
Renaissance may be the least expensive surgical assist “robot” on the market yet it is addressing a comparatively high priced set of procedures. Furthermore, the types of surgeries that Mazor is migrating to (complex surgeries and neuro surgery) are procedures that routinely cost more than $100, 000 per case and have a much higher potential for error or poor outcome than, say, knee or hip reconstruction.
The other major orthopedic robot company, MAKO, offers hospitals a surgical assist system which costs just under $1 million and is most often used for knee reconstruction surgery, a procedure that most hospitals charge about $25, 000 – $45, 000 for. So one MAKO Rio costs about as much as 30 to 40 knee recon surgeries.
MAKO’s Rio generates approximately $5, 000 per procedure in disposables and implants. Mazor’s Renaissance generates about $1, 500 per case currently. While Mazor had announced in 2011 that its Emerald pedicle screw system was cleared by the FDA, it has not yet started to market it. The potential synergy with implants is clear: it could further increase surgical efficiency and flow, and the potential per-case revenues for Mazor should rise substantially.
MAKO and Mazor’s system have several similarities. Both employ computer technology to improve pre-surgery planning and, in collaboration with the surgeon, perform a more accurate and precise surgery to, in turn, improve patient outcomes.
Both systems start with an accurate CT model of the patient’s anatomy and both use those pre-operative images to create a three-dimensional dataset which works as an exact geometrical map of normal and pathological tissues and structures.
Both systems analyze and process the image data. Using each system’s virtual 3D anatomical model, users can refine their diagnosis and simulate the upcoming surgery. When all surgical planning is done, the robot then uses that data to program pre-planned actions during actual surgery.
During surgery, both the RIO and Renaissance use these programmed images and surgeon generated datasets to direct the actual surgery.
But after this the two systems diverge. MAKO’s system is a shared-control system and its key feature is the Haptic control which gives the surgeon tactile feedback. Mazor’s uses its controller to guide the instruments and implants. It is not, in fact, a shared control system. It’s a semi-active robot that allows surgeons to maintain full control while being guided to the entry point and trajectory that they planned.
Neurosurgery
Historically, surgical robots have found greatest acceptance in the most technically challenging procedures like neurosurgery (first used in the 1980s), oral and maxillofacial surgery (extremely tight tolerances), laparoscopic abdominal or gynecological surgery and cardiac surgery.
The great innovation of Mazor’s system is that it is also tackling the most technically challenging cases like complex spine or brain surgery, but it is doing so with a distinctly more elegant, compact and much less expensive system.
By definition, complex surgeries have a greater risk of misplaced implants and surgeon error. A 2007 meta-analysis of pedicle screw placements (Pedicle Screw Placement Accuracy: a Meta-Analysis Kosmopoulos V, Schizas C.; Spine 2007 Feb 1;32(3):E111-20) reported 10% misplacements when pedicle screws are implanted freehand. Another study (Trends, Major Medical Complications, and Charges Associated With Surgery for Lumbar Spinal Stenosis in Older Adults. JAMA April 2010) reported that major medical complications were reported in 5.2% of complex fusion procedures.
Accepting the maxim that the cost of precision, i.e., the purchase price and ongoing maintenance of a surgical assist device, must be less than the cost of imprecision, the fact that Mazor is targeting big ticket, complex surgeries which have comparatively high rates of complications and less than satisfactory outcomes is just plain smart.
In the same press release where Mazor’s CEO Ori Hadomi announced that his sales had jumped 470% to more than 11 million ILS for the June quarter, he also informed his lucky shareholders that his little Pepsi can of a surgical guidance device had now been used to place more than 20, 000 implants worldwide.
No doubt Mazor’s booth at this coming NASS will be one of the most crowded of the show. It will be fascinating.
