Cervical Degenerative Disc Disorder
Conditions
Brief summary
This study is intended to demonstrate that the Simplify® Cervical Artificial Disc (Simplify® Disc) is at least as safe and effective as conventional anterior cervical discectomy and fusion (ACDF) when used to treat two contiguous discs from C3 to C7 following discectomy at two contiguous levels for intractable radiculopathy (arm pain and/or a neurological deficit) with neck pain or myelopathy due to abnormalities localized to the levels of the two contiguous disc spaces in subjects who are unresponsive to conservative management.
Detailed description
The objective of this clinical study is to evaluate the safety and effectiveness of the two-level Simplify® Disc compared to conventional two-level ACDF in skeletally mature patients for reconstruction of two contiguous discs from C3 to C7 following discectomy at two contiguous levels for intractable radiculopathy (arm pain and/or a neurological deficit) with neck pain or myelopathy due to abnormalities localized to the levels of the two contiguous disc spaces that are unresponsive to conservative management.
Interventions
DEVICESimplify Disc
Simplify Disc at two levels of the cervical spine
Sponsors
NuVasive
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Has cervical degenerative disc disease at two (2) adjacent cervical levels (from C3 C7) requiring surgical treatment and involving intractable radiculopathy, myelopathy, or both; * Has a herniated disc and/or osteophyte formation at each level to be treated that is producing symptomatic nerve root and/or spinal cord compression. The condition is documented by patient history (e.g., neck pain with arm pain, functional deficit and/or neurological deficit), and the requirement for surgical treatment is evidenced by radiographic studies (e.g., CT, MRI, x-rays, etc.); * Has been unresponsive to non-operative treatment for at least six weeks or has the presence of progressive symptoms or signs of nerve root/spinal cord compression in the face of continued non-operative management; * Has no previous surgical intervention at the involved levels or any subsequent planned/staged surgical procedure at the involved or adjacent level(s); * Must be at least 18 years of age and be skeletally mature at the time of surgery; * Has a preoperative Neck Disability Index (NDI) ≥ 30; * Has a preoperative neck pain score \> 8 based on the preoperative Neck and Arm Pain Questionnaire; * If a female of childbearing potential, patient is non-pregnant, non-nursing, and agrees not to become pregnant during the study period; * Is willing to comply with the study plan and sign the Patient Informed Consent Form.
Exclusion criteria
* Has a cervical spinal condition other than symptomatic cervical DDD requiring surgical treatment at the involved levels; * Has documented or diagnosed cervical instability relative to adjacent segments at either level, defined by dynamic (flexion/extension) radiographs showing: * Sagittal plane translation \> 3.5 mm, or * Sagittal plane angulation \> 20°; * Has more than two cervical levels requiring surgical treatment; * Has a fused level (or artificial disc replacement) adjacent to the levels to be treated; * Has severe pathology of the facet joints of the involved vertebral bodies; * Has had previous surgical intervention at either one or both of the involved levels or at adjacent levels; * Axial neck pain only (no radicular or myelopathy symptoms); * Has been previously diagnosed with osteopenia or osteomalacia; * Has any of the following that may be associated with a diagnosis of osteoporosis (if Yes to any of the below risk factors, a DEXA Scan will be required to determine eligibility): * Postmenopausal non-black female over 60 years of age who weighs less than 140 pounds; * Postmenopausal female who has sustained a non-traumatic hip, spine, or wrist fracture; * Male over the age of 70; * Male over the age of 60 who has sustained a non-traumatic hip or spine fracture. * If the level of bone mineral density is a T score of -1.5 or lower (i.e., -1.6, 1.7, etc.), then the patient is excluded from the study * Has presence of spinal metastases; * Has overt or active bacterial infection, either local or systemic; * Has insulin-dependent diabetes; * Has chronic or acute renal failure or prior history of renal disease; * Known PEEK, ceramic, titanium allergy; * Is mentally incompetent (if questionable, obtain psychiatric consult); * Is a prisoner; * Is pregnant; * Is currently an alcohol and/or drug abuser or currently undergoing treatment for alcohol and/or drug abuse; * Is involved with current or pending litigation regarding a spinal condition; * Has received drugs that may interfere with bone metabolism within two weeks prior to the planned date of spinal surgery (e.g., steroids or methotrexate), excluding routine perioperative anti-inflammatory drugs; * Has a history of an endocrine or metabolic disorder known to affect osteogenesis (e.g., Paget's Disease, renal osteodystrophy, Ehlers-Danlos Syndrome, or osteogenesis imperfecta); * Has a condition that requires postoperative medications that interfere with the stability of the implant, such as steroids. (This does not include low-dose aspirin for prophylactic anticoagulation and routine perioperative anti-inflammatory drugs); * Has received treatment with an investigational therapy within 28 days prior to implantation surgery or such treatment is planned during the 16 weeks following implantation.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Composite Clinical Success (CCS) Rate of the Simplify® Disc | 24 Months | Individual success is defined as at least a 15 point improvement in Neck Disability Index (NDI) Score at 24 months compared with baseline, maintenance or improvement in neurologic status at 24 months compared with baseline, no additional surgical procedure at the index level within 24 months, and the absence of a serious adverse event classified as implant-associated or implant/surgical procedure-associated within 24 months. NDI scale is reported in a range from 0 - 100, with 0 consistent with best ability to function and 100 with worst ability to function. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery) | Baseline, 3mos | Time to recovery is defined as time to first 15-point improvement in NDI NDI scale is reported in a range from 0 - 100, with 0 consistent with best ability to function and 100 with worst ability to function. |
| Neck Pain Intensity Questionnaire | Baseline, 24mos. | Changes of at least 2 points on a 10-point scale will be regarded as clinically significant (0=no pain; 10=worst pain) |
| Arm Pain Intensity Questionnaire | Baseline, 24mos. | Changes of at least 2 points on a 10-point scale will be regarded as clinically significant (0=no pain; 10=worst pain) |
| Patient Questionnaires- Treatment Satisfaction Survey | Baseline, 24mos. | Question 1 - I am satisfied with the results of my surgery was compared between groups at Month 24. Answer options ranged from definitely true to definitely false. |
| SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement | Baseline, 24mos | The PCS is a sub-score of the SF-36. The SF-36 is a multipurpose survey with 36 questions. The questions were combined, scored, and weighted to create two scores that provide glimpses into mental and physical functioning and overall health-related quality-of-life. Higher scores indicate better outcomes. Scores range from 0-50. Maintenance or improvement was defined as PCS(Postop) - PCS(Preop) ≥0. |
| SF-36 Mental Component Score (MCS) Maintenance or Improvement | Baseline, 24mos. | The MCS is a sub-score of the SF-36. The SF-36 is a multipurpose survey with 36 questions. The questions were combined, scored, and weighted to create two scores that provide glimpses into mental and physical functioning and overall health-related quality-of-life. Higher scores indicate better outcomes. Scores range from 0-50. Maintenance or improvement was defined as MCS(Postop) - MCS(Preop) ≥0. |
| Dysphagia Handicap Index (DHI) | Baseline, 24mos. | Dysphagia Handicap Index (DHI scale) for the investigational Simplify® Disc at 24 months compared to baseline. A higher score is indicative of a less desirable outcome. It is scored 0-100. Data was not collected on DHI in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design. |
| Neurological Status | Baseline, 24mos | Neurological success was defined as maintenance or improvement in neurologic status at Month 24 as compared to baseline, as determined by the independent Clinical Events Committee (CEC). The CEC reviews neurological exams of motor, sensory, reflex, and myelopathic gait to make an adjudication determination. |
| Change in Average Disc Height (Superior Index Level) | Baseline, 24mos. | Average disc height (superior index level) at 24 months was compared to the baseline measurement and the change was calculated. Measurements were scored by an independent core lab. Average disc height is calculated as the simple average of the anterior and posterior disc heights. Data was not collected on disc height in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design. |
| Change in Average Disc Height (Inferior Index Level) | Baseline, 24M | Average disc height (inferior index level) at 24 months was compared to the baseline measurement and the change was calculated. Measurements were scored by an independent core lab. Average disc height is calculated as the simple average of the anterior and posterior disc heights. Data was not collected on disc height in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design. |
| Superior Adjacent Level Disc Degeneration (ALDD) | Baseline, 24mos. | Outcome reports the number and percentage of subjects with adjacent level disc degeneration (ALDD) above the index level based on X-ray images. Degeneration was graded as none (no degenerative changes), doubtful (Minimal osteophytosis only), minimal (Definite osteophytosis with some sclerosis of anterior part of vertebral plates), moderate (Marked osteophytosis and sclerosis of vertebral plates with slight narrowing of disk space), severe (Large osteophytes, marked sclerosis of vertebral plates, and marked narrowing of disk space), indeterminate, or unable to assess. Data was not collected on ALDD in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design. |
| Inferior Adjacent Level Disc Degeneration (ALDD) | Baseline, 24mos. | Outcome reports the number and percentage of subjects with adjacent level disc degeneration (ALDD) below the index level based on X-ray images. Degeneration was graded as none (no degenerative changes), doubtful (Minimal osteophytosis only), minimal (Definite osteophytosis with some sclerosis of anterior part of vertebral plates), moderate (Marked osteophytosis and sclerosis of vertebral plates with slight narrowing of disk space), severe (Large osteophytes, marked sclerosis of vertebral plates, and marked narrowing of disk space), indeterminate, or unable to assess. Data was not collected on ALDD in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design. |
| Facet Degeneration (Superior Index Level) | Baseline, 24mos. | Facet degeneration was assessed using MRI for the investigational Simplify Disc at 24 months compared to baseline. Degeneration was graded as none (normal facet joint space), mild (narrowing of the facet joint space and / or small osteophytes and / or mild hypertrophy of the articular process), moderate (narrowing of the facet joint space and/or moderate osteophytes and/or moderate hypertrophy of the articular process and / or mild subarticular bone erosions), severe (Narrowing of the facet joint space and/or large osteophytes and/or severe hypertrophy of the articular process and/or severe subarticular bone erosions and/or subchondral cysts), indeterminate, or unable to assess. Facet degeneration was not assessed in the ACDF historical control group, as there is no 24 month MRI. This was pre-specified in the study design. |
| Facet Degeneration (Inferior Index Level) | Baseline, 24mos. | Facet degeneration was assessed using MRI for the investigational Simplify Disc at 24 months compared to baseline. Degeneration was graded as none (normal facet joint space), mild (narrowing of the facet joint space and / or small osteophytes and / or mild hypertrophy of the articular process), moderate (narrowing of the facet joint space and/or moderate osteophytes and/or moderate hypertrophy of the articular process and / or mild subarticular bone erosions), severe (Narrowing of the facet joint space and/or large osteophytes and/or severe hypertrophy of the articular process and/or severe subarticular bone erosions and/or subchondral cysts), indeterminate, or unable to assess. Facet degeneration was not assessed in the ACDF historical control group, as there is no 24 month MRI. This was pre-specified in the study design. |
| Physician's Perception of Results | Baseline, 24mos. | Results at 24 months for the investigational Simplify® Disc and at 24 months for the control ACDF will also be categorized by the physician according to their perception of the results. Available responses include excellent, good, fair, and poor. Maintenance or improvement was defined as either maintenance of the assigned preoperative grade or any shift to a more favorable grade postoperatively (e.g. poor to fair, fair to good). |
Countries
United States
Participant flow
Pre-assignment details
Historical control was used for control arm. The only subjects enrolled under this study were investigational subjects (Simplify Disc).
Participants by arm
| Arm | Count |
|---|---|
| Simplify Disc Simplify Disc at two levels of the cervical spine
Simplify Disc: Simplify Disc at two levels of the cervical spine | 182 |
| Historical Control This study will utilize a non-concurrent historical control with subject-level data on a parallel group design. The historical control group will be formed from the randomized ACDF arm of a previously completed two level cervical disc trial. | 170 |
| Total | 352 |
Baseline characteristics
| Characteristic | Historical Control | Total | Simplify Disc |
|---|---|---|---|
| Age, Continuous | 47.45 years STANDARD_DEVIATION 7.89 | 48.38 years STANDARD_DEVIATION 8.7 | 49.25 years STANDARD_DEVIATION 9.39 |
| Ethnicity (NIH/OMB) Hispanic or Latino | — | 5 Participants | 5 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | — | 177 Participants | 177 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | — | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 3 Participants | 4 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 6 Participants | 12 Participants | 6 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 4 Participants | 9 Participants | 5 Participants |
| Race (NIH/OMB) White | 157 Participants | 327 Participants | 170 Participants |
| Region of Enrollment United States | 170 participants | 352 participants | 182 participants |
| Sex: Female, Male Female | 89 Participants | 184 Participants | 95 Participants |
| Sex: Female, Male Male | 81 Participants | 168 Participants | 87 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 2 / 182 | 1 / 170 |
| other Total, other adverse events | 96 / 182 | 145 / 170 |
| serious Total, serious adverse events | 32 / 182 | 62 / 170 |
Outcome results
Primary
Composite Clinical Success (CCS) Rate of the Simplify® Disc
Individual success is defined as at least a 15 point improvement in Neck Disability Index (NDI) Score at 24 months compared with baseline, maintenance or improvement in neurologic status at 24 months compared with baseline, no additional surgical procedure at the index level within 24 months, and the absence of a serious adverse event classified as implant-associated or implant/surgical procedure-associated within 24 months. NDI scale is reported in a range from 0 - 100, with 0 consistent with best ability to function and 100 with worst ability to function.
Time frame: 24 Months
Population: While 168 Simplify Disc subjects and 127 historical control subjects were considered completers for subject accounting purposes, 173 (Simplify Disc) and 145 (ACDF) subjects were evaluable for composite clinical success. This is due to the fact that some subjects were known failures prior to the 24-month visit.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Simplify Disc | Composite Clinical Success (CCS) Rate of the Simplify® Disc | 153 Participants |
| Historical Control | Composite Clinical Success (CCS) Rate of the Simplify® Disc | 105 Participants |
p-value: 0.017t-test, 1 sided
Secondary
Arm Pain Intensity Questionnaire
Changes of at least 2 points on a 10-point scale will be regarded as clinically significant (0=no pain; 10=worst pain)
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 158 Simplify Disc subjects had change in Arm Pain Intensity data at 24 months due to missed questionnaires.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Arm Pain Intensity Questionnaire | Success | 142 Participants |
| Simplify Disc | Arm Pain Intensity Questionnaire | Failure | 16 Participants |
| Historical Control | Arm Pain Intensity Questionnaire | Success | 108 Participants |
| Historical Control | Arm Pain Intensity Questionnaire | Failure | 19 Participants |
Secondary
Change in Average Disc Height (Inferior Index Level)
Average disc height (inferior index level) at 24 months was compared to the baseline measurement and the change was calculated. Measurements were scored by an independent core lab. Average disc height is calculated as the simple average of the anterior and posterior disc heights. Data was not collected on disc height in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design.
Time frame: Baseline, 24M
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 157 Simplify Disc subjects had evaluable radiographs for this assessment at 24 months due to missed x-rays or poor image quality which limited analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Simplify Disc | Change in Average Disc Height (Inferior Index Level) | 0.84 mm | Standard Deviation 0.96 |
Secondary
Change in Average Disc Height (Superior Index Level)
Average disc height (superior index level) at 24 months was compared to the baseline measurement and the change was calculated. Measurements were scored by an independent core lab. Average disc height is calculated as the simple average of the anterior and posterior disc heights. Data was not collected on disc height in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 164 Simplify Disc subjects had evaluable radiographs for this assessment at 24 months due to missed x-rays or poor image quality which limited analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Simplify Disc | Change in Average Disc Height (Superior Index Level) | 1.19 mm | Standard Deviation 0.81 |
Secondary
Dysphagia Handicap Index (DHI)
Dysphagia Handicap Index (DHI scale) for the investigational Simplify® Disc at 24 months compared to baseline. A higher score is indicative of a less desirable outcome. It is scored 0-100. Data was not collected on DHI in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Simplify Disc | Dysphagia Handicap Index (DHI) | 6.9 score on a scale | Standard Deviation 10.7 |
Secondary
Facet Degeneration (Inferior Index Level)
Facet degeneration was assessed using MRI for the investigational Simplify Disc at 24 months compared to baseline. Degeneration was graded as none (normal facet joint space), mild (narrowing of the facet joint space and / or small osteophytes and / or mild hypertrophy of the articular process), moderate (narrowing of the facet joint space and/or moderate osteophytes and/or moderate hypertrophy of the articular process and / or mild subarticular bone erosions), severe (Narrowing of the facet joint space and/or large osteophytes and/or severe hypertrophy of the articular process and/or severe subarticular bone erosions and/or subchondral cysts), indeterminate, or unable to assess. Facet degeneration was not assessed in the ACDF historical control group, as there is no 24 month MRI. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 166 Simplify Disc subjects had an evaluable MRI for this assessment at 24 months due to missed MRIs.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Facet Degeneration (Inferior Index Level) | None | 96 Participants |
| Simplify Disc | Facet Degeneration (Inferior Index Level) | Mild | 60 Participants |
| Simplify Disc | Facet Degeneration (Inferior Index Level) | Moderate | 8 Participants |
| Simplify Disc | Facet Degeneration (Inferior Index Level) | Severe | 0 Participants |
| Simplify Disc | Facet Degeneration (Inferior Index Level) | Indeterminate | 0 Participants |
| Simplify Disc | Facet Degeneration (Inferior Index Level) | Unable to assess | 2 Participants |
Secondary
Facet Degeneration (Superior Index Level)
Facet degeneration was assessed using MRI for the investigational Simplify Disc at 24 months compared to baseline. Degeneration was graded as none (normal facet joint space), mild (narrowing of the facet joint space and / or small osteophytes and / or mild hypertrophy of the articular process), moderate (narrowing of the facet joint space and/or moderate osteophytes and/or moderate hypertrophy of the articular process and / or mild subarticular bone erosions), severe (Narrowing of the facet joint space and/or large osteophytes and/or severe hypertrophy of the articular process and/or severe subarticular bone erosions and/or subchondral cysts), indeterminate, or unable to assess. Facet degeneration was not assessed in the ACDF historical control group, as there is no 24 month MRI. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 166 Simplify Disc subjects had an evaluable MRI for this assessment at 24 months due to missed MRIs.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Facet Degeneration (Superior Index Level) | None | 87 Participants |
| Simplify Disc | Facet Degeneration (Superior Index Level) | Mild | 64 Participants |
| Simplify Disc | Facet Degeneration (Superior Index Level) | Moderate | 13 Participants |
| Simplify Disc | Facet Degeneration (Superior Index Level) | Severe | 0 Participants |
| Simplify Disc | Facet Degeneration (Superior Index Level) | Indeterminate | 0 Participants |
| Simplify Disc | Facet Degeneration (Superior Index Level) | Unable to assess | 2 Participants |
Secondary
Inferior Adjacent Level Disc Degeneration (ALDD)
Outcome reports the number and percentage of subjects with adjacent level disc degeneration (ALDD) below the index level based on X-ray images. Degeneration was graded as none (no degenerative changes), doubtful (Minimal osteophytosis only), minimal (Definite osteophytosis with some sclerosis of anterior part of vertebral plates), moderate (Marked osteophytosis and sclerosis of vertebral plates with slight narrowing of disk space), severe (Large osteophytes, marked sclerosis of vertebral plates, and marked narrowing of disk space), indeterminate, or unable to assess. Data was not collected on ALDD in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 166 Simplify Disc subjects had evaluable radiographs for this assessment at 24 months due to missed x-rays or poor image quality which limited analysis.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | None | 110 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Doubtful | 20 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Minimal | 9 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Moderate | 2 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Severe | 1 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Indeterminate | 21 Participants |
| Simplify Disc | Inferior Adjacent Level Disc Degeneration (ALDD) | Unable to assess | 3 Participants |
Secondary
Neck Pain Intensity Questionnaire
Changes of at least 2 points on a 10-point scale will be regarded as clinically significant (0=no pain; 10=worst pain)
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 158 Simplify Disc subjects had change in Neck Pain Intensity data at 24 months due to missed questionnaires.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Neck Pain Intensity Questionnaire | Success | 147 Participants |
| Simplify Disc | Neck Pain Intensity Questionnaire | Fail | 11 Participants |
| Historical Control | Neck Pain Intensity Questionnaire | Success | 110 Participants |
| Historical Control | Neck Pain Intensity Questionnaire | Fail | 17 Participants |
Secondary
Neurological Status
Neurological success was defined as maintenance or improvement in neurologic status at Month 24 as compared to baseline, as determined by the independent Clinical Events Committee (CEC). The CEC reviews neurological exams of motor, sensory, reflex, and myelopathic gait to make an adjudication determination.
Time frame: Baseline, 24mos
Population: While 127 historical control subjects were considered completers for subject accounting purposes, 128 historical subjects had sufficient neurological data available for CEC determination of maintenance or improvement of neurological status.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Neurological Status | Deteriorated | 0 Participants |
| Simplify Disc | Neurological Status | Improved | 140 Participants |
| Simplify Disc | Neurological Status | Maintained | 28 Participants |
| Historical Control | Neurological Status | Maintained | 19 Participants |
| Historical Control | Neurological Status | Deteriorated | 3 Participants |
| Historical Control | Neurological Status | Improved | 106 Participants |
Secondary
Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery)
Time to recovery is defined as time to first 15-point improvement in NDI NDI scale is reported in a range from 0 - 100, with 0 consistent with best ability to function and 100 with worst ability to function.
Time frame: Baseline, 3mos
Population: While 168 Simplify Disc subjects and 127 historical control subjects were considered completers for subject accounting purposes at 24 months, 177 (Simplify Disc) and 154 (ACDF) subjects had evaluable change in NDI scores at 3 months.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery) | 15-Point Improvement (Yes) | 160 Participants |
| Simplify Disc | Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery) | 15-Point Improvement (No) | 17 Participants |
| Historical Control | Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery) | 15-Point Improvement (Yes) | 123 Participants |
| Historical Control | Number of Subjects With 15-point Improvement in NDI at 3 Months (Time to Recovery) | 15-Point Improvement (No) | 31 Participants |
Secondary
Patient Questionnaires- Treatment Satisfaction Survey
Question 1 - I am satisfied with the results of my surgery was compared between groups at Month 24. Answer options ranged from definitely true to definitely false.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects and 127 historical control subjects were considered completers for subject accounting purposes, 172 (Simplify Disc) and 145 (ACDF) subjects had evaluable treatment satisfaction data at 24 months.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Patient Questionnaires- Treatment Satisfaction Survey | Mostly true | 26 Participants |
| Simplify Disc | Patient Questionnaires- Treatment Satisfaction Survey | Mostly false | 5 Participants |
| Simplify Disc | Patient Questionnaires- Treatment Satisfaction Survey | Don't know | 8 Participants |
| Simplify Disc | Patient Questionnaires- Treatment Satisfaction Survey | Definitely false | 2 Participants |
| Simplify Disc | Patient Questionnaires- Treatment Satisfaction Survey | Definitely true | 131 Participants |
| Historical Control | Patient Questionnaires- Treatment Satisfaction Survey | Definitely false | 5 Participants |
| Historical Control | Patient Questionnaires- Treatment Satisfaction Survey | Definitely true | 99 Participants |
| Historical Control | Patient Questionnaires- Treatment Satisfaction Survey | Mostly true | 30 Participants |
| Historical Control | Patient Questionnaires- Treatment Satisfaction Survey | Don't know | 7 Participants |
| Historical Control | Patient Questionnaires- Treatment Satisfaction Survey | Mostly false | 4 Participants |
Secondary
Physician's Perception of Results
Results at 24 months for the investigational Simplify® Disc and at 24 months for the control ACDF will also be categorized by the physician according to their perception of the results. Available responses include excellent, good, fair, and poor. Maintenance or improvement was defined as either maintenance of the assigned preoperative grade or any shift to a more favorable grade postoperatively (e.g. poor to fair, fair to good).
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects and 127 historical control subjects were considered completers for subject accounting purposes, 170 (Simplify Disc) and 145 (ACDF) subjects had evaluable Physician's Perception of Results data at 24 months.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Physician's Perception of Results | Excellent | 139 Participants |
| Simplify Disc | Physician's Perception of Results | Good | 26 Participants |
| Simplify Disc | Physician's Perception of Results | Fair | 3 Participants |
| Simplify Disc | Physician's Perception of Results | Poor | 2 Participants |
| Historical Control | Physician's Perception of Results | Poor | 3 Participants |
| Historical Control | Physician's Perception of Results | Excellent | 85 Participants |
| Historical Control | Physician's Perception of Results | Fair | 15 Participants |
| Historical Control | Physician's Perception of Results | Good | 42 Participants |
Secondary
SF-36 Mental Component Score (MCS) Maintenance or Improvement
The MCS is a sub-score of the SF-36. The SF-36 is a multipurpose survey with 36 questions. The questions were combined, scored, and weighted to create two scores that provide glimpses into mental and physical functioning and overall health-related quality-of-life. Higher scores indicate better outcomes. Scores range from 0-50. Maintenance or improvement was defined as MCS(Postop) - MCS(Preop) ≥0.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 158 Simplify Disc subjects had SF-36 data available at 24 months due to missed questionnaires.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | SF-36 Mental Component Score (MCS) Maintenance or Improvement | Maintenance or improvement | 125 Participants |
| Simplify Disc | SF-36 Mental Component Score (MCS) Maintenance or Improvement | Absence of maintenance or improvement | 33 Participants |
| Historical Control | SF-36 Mental Component Score (MCS) Maintenance or Improvement | Maintenance or improvement | 94 Participants |
| Historical Control | SF-36 Mental Component Score (MCS) Maintenance or Improvement | Absence of maintenance or improvement | 33 Participants |
Secondary
SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement
The PCS is a sub-score of the SF-36. The SF-36 is a multipurpose survey with 36 questions. The questions were combined, scored, and weighted to create two scores that provide glimpses into mental and physical functioning and overall health-related quality-of-life. Higher scores indicate better outcomes. Scores range from 0-50. Maintenance or improvement was defined as PCS(Postop) - PCS(Preop) ≥0.
Time frame: Baseline, 24mos
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 158 Simplify Disc subjects had SF-36 data available at 24 months due to missed questionnaires.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement | Maintenance or improvement | 146 Participants |
| Simplify Disc | SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement | Absence of maintenance or improvement | 12 Participants |
| Historical Control | SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement | Maintenance or improvement | 114 Participants |
| Historical Control | SF-36v2 Health Survey Physical Component Score (PCS) Maintenance or Improvement | Absence of maintenance or improvement | 13 Participants |
Secondary
Superior Adjacent Level Disc Degeneration (ALDD)
Outcome reports the number and percentage of subjects with adjacent level disc degeneration (ALDD) above the index level based on X-ray images. Degeneration was graded as none (no degenerative changes), doubtful (Minimal osteophytosis only), minimal (Definite osteophytosis with some sclerosis of anterior part of vertebral plates), moderate (Marked osteophytosis and sclerosis of vertebral plates with slight narrowing of disk space), severe (Large osteophytes, marked sclerosis of vertebral plates, and marked narrowing of disk space), indeterminate, or unable to assess. Data was not collected on ALDD in the historical ACDF control group. Only Simplify Disc subjects are reported. This was pre-specified in the study design.
Time frame: Baseline, 24mos.
Population: While 168 Simplify Disc subjects were considered completers for subject accounting purposes, 166 Simplify Disc subjects had evaluable radiographs for this assessment at 24 months due to missed x-rays or poor image quality which limited analysis.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | None | 100 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Doubtful | 45 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Minimal | 16 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Moderate | 2 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Severe | 1 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Unable to assess | 2 Participants |
| Simplify Disc | Superior Adjacent Level Disc Degeneration (ALDD) | Indeterminate | 0 Participants |