The Spinal Kinetics M6 artificial cervical disc replacement is designed to replicate the structure and performance of a healthy disc. Its innovative design incorporates an artificial nucleus to allow shock absorption and a woven fiber annulus for controlled motion in all directions.
These characteristics accurately replicate the healthy disc, allowing the disc replacement implant to work in concert with the remaining human discs.
Unlike earlier disc replacement designs with M6 the resulting natural functionality of the entire spinal curve should provide the best chance for a full recovery, and prevent additional adjacent level degeneration. This "Quality of Motion" is a major benefit not available in any other implant we have seen!
From the M6 Studies
"The kinematic signatures of the intact human disc and the M6 artificial disc are nearly identical"
"There has been no serious device-related adverse events, surgical re-interventions, or evidence of device migration, expulsion, or subsidence in this study group"
"Findings indicate substantial clinical improvement for all function, pain, and quality of life outcomes in addition to maintenance of ROM and increase in disc height at the treated level(s). The findings also exhibit an acceptable safety profile, as indicated by the absence of serious adverse events and reoperations following arthroplasty with a next-generation artificial cervical disc replacement device.
"The M6 disc replacement implant remains fully intact and functional after functional kinematic testing to 20 Million cycles of
combined motion; physiologic dynamic compression, compression
shear, and torsion; creep to the equivalent of 100 years! Click here for M6 Studies
We have been using the M6 implant for several years and has seen excellent results and reduced complications.
These complication risks include adjacent disc degeneration and facet joint damage found with early “ball in socket” designs, not seen in the M6 patients, and M6 has not been found to cause the ossification, as found in other early generation compressible implants.
The Spinal Kinetics M6 has received CE Mark (European FDA) approval for use in the European Economic Area countries. The CE marking certifies that a product has met EU consumer safety, health or environmental requirements.
The Spinal Kinetics M6 has not been approved for use in the US and no trials are underway at this time,
Watch a video on "The evolution of Disc Replacement"
Disc Replacement Options and "Quality of Motion"
Disc replacement implants fall into two distinct categories, compressible, and non-compressible.
Non compressible devices include Fixed Center of Rotation; ball-and-socket designs, and Mobile Center of Rotation; mobile core and ball and trough designs.
Aside from the obvious lack of shock absorption, non-compressible implants have several distinct characteristics.
A healthy disc provides a graded resistance to motion. Although, these non-compressible disc replacement implants retain motion, unlike fusion, the motion is uncontrolled. Adding load can make the motion characteristics even more unpredictable. The result can be motion which is not intended in the design or is sporadic. This is also referred to as stick-slip-friction. Because of this, facet joints may be overloaded, muscles are required to work harder, and adjacent level damage can occur. On the other hand, in a case where additional stability is desired, due to advanced disease or other factors, an implant with a fixed center of rotation, may be desired.
Compressible implants have the obvious benefit of shock absorption protection, but can also provide the required graded variable resistance to motion like a healthy disc. One of the first implants to achieve this was the Bryan cervical disc. Although this implant provided graded resistance, calcification was reported in as much as 12% of the cases studied. This issue has been resolved in more advanced implants like the M6 Cervical Disc. By provided the graded variable resistance, replicating a healthy disc, the M6 reduces facet and adjacent level complications. This "quality of motion" under load not only maintains a physiologically correct motion dynamic, it also is not as sensitive to placement variables as the earlier implants.
Careful evaluation by experienced surgeons is critical to insure that the correct implant options are chosen for each level based on many factors. Our surgeons the experience and the implant options needed to make sure the best possible outcome is achieved.
M6 Testimonial Felicia, 3 level M6 Cervical Disc Replacement,
Sept 2008.
I have had neck pain for over 10 years. All the doctors told me that I did not want surgery. The only option in the U.S. was to fuse, and there were no guarantees I would be pain free. My surgeon in the U.S. was familiar with the M6. I had three cervical disc replacements and have had no trouble at all. The experience in Germany was great, I felt like I was on vacation. The hospital and staff were wonderful.
June 2010 Update Fleicia is doing so well that she competed in the Eppie’s Great Race!
A “no swim” triathlon in Sacramento CA. She ran 5.82 miles, biked 12.5 miles, and paddled a kayak 6.35 miles.
A feasibility trial was conducted to evaluate the initial safety and clinical use of a next-generation artificial cervical disc (M6-C artificial cervical disc; Spinal Kinetics, Sunnyvale, CA) for the treatment of patients with symptomatic degenerative cervical radiculopathy. A standardized battery of validated outcome measures was utilized to assess condition-specific functional impairment, pain severity, and quality of life.
Methods
Thirty-six consecutive patients were implanted with the M6-C disc and complete clinical and radiographic outcomes for 25 patients (mean age, 44.5 +- 10.1 years) with radiographically-confirmed cervical disc disease and symptomatic radiculopathy unresponsive to conservative medical management are included in this report. All patients had disc-osteophyte complex causing neural compression and were treated with discectomy and artificial cervical disc replacement at either single level (n = 12) or 2-levels (n = 13). Functional impairment was evaluated using the Neck Disability Index (NDI). Evaluation of arm and neck pain severity utilized a standard 11-point numeric scale, and health-related quality of life was evaluated with the SF-36 Health Survey. Quantitative radiographic assessments of intervertebral motion were performed using specialized motion analysis software, QMA (Quantitative Motion Analysis; Medical Metrics, Houston, TX). All outcome measures were evaluated pre-treatment and at 6 weeks, 3, 6, 12, and 24 months.
Results
The mean NDI score improved from 51.6 +- 11.3% pre-treatment to 27.9 +- 16.9% at 24 months, representing an approximate 46% improvement (P < .0001). The mean arm pain score improved from 6.9 ± 2.5 pre-treatment to 3.9 +- 3.1 at 24 months (43%, P = .0006). The mean neck pain score improved from 7.8 +- 2.0 pre-treatment to 3.8 ± 3.0 at 24 months (51%, P < .0001). The mean PCS score of the SF-36 improved from 34.8 +- 7.8 pre-treatment to 43.8 +- 9.3 by 24 months (26%, P = .0006). Subgroup analyses found that patients treated at single level and those with a shorter duration of symptoms showed better functional results. By 24 months, the mean range of motion (ROM) value at the treated level had returned to approximately pretreatment levels (12.2 vs 11.1 degrees). There were no serious device-related adverse events, surgical re-interventions or radiographic evidence of heterotopic ossification, device migration, or expulsion in this study group.
Conclusions
These findings indicate substantial clinical improvement for all function, pain, and quality of life outcomes in addition to maintenance of ROM and increase in disc height at the treated level(s). The findings also exhibit an acceptable safety profile, as indicated by the absence of serious adverse events and reoperations following arthroplasty with a next-generation artificial cervical disc replacement device.
Lifespan of the Spinal Kinetics M6-C Cervical Disc Replacement
The M6-C was subjected to rigorous testing which confirms the
inherent robustness of the device. The disc remains fully intact
and functional after functional kinematic testing to 20 Million cycles of
combined motion; physiologic dynamic compression, compression
shear, and torsion; creep to the equivalent of 100 years; and worst
case physiologic extension over 30,000 cycles. Even when highly
nonphysiologic static loads are applied, the device does not
exhibit any mechanical or functional failures.
See Lifespan of the Spinal Kinetics M6-C Cervical Disc Replacement > >
