5-Year Global Study on MAST™ Minimally Invasive Fusion Procedures to Treat Degenerative Lumbar Spine (MASTERS-D2) (MASTERS-D2)

A Prospective, 5-Year Global Study on MAST™ Minimally Invasive Fusion Procedures for the Treatment of the Degenerative Lumbar Spine

The purpose of this study is

• to evaluate the effectiveness of MAST techniques for anterior/lateral and posterior approaches in Degenerative Disc Disease (DDD) patients with spondylolisthesis (≥ grade I).
• To assess how single or double level MAST(Minimal Access Spinal Technologies) fusion procedures PLIF (Posterior Lumbar Interbody Fusion), TLIF (Transforaminal Lumbar Interbody Fusion), DLIF (Direct Lateral Interbody Fusion), OLIF (Oblique Lumbar Interbody Fusion), ALIF (Anterior Lumbar Interbody Fusion), or MIDLF (Midline Lumbar Interbody Fusion) are used in surgical practice and to describe long-term safety and effectiveness in a broad patient population of patients with degenerative lumbar disc disease .

Study Overview

• Status: Completed
• Conditions: Intervertebral Disc Degeneration
• Intervention / Treatment: Device: Minimally invasive lumbar fusion

Detailed Description

In this Prospective, Global (multi center), Post Market Release (PMR) Study, Patients will be submitted to a single or double level instrumented fusion procedure using a PLIF, TLIF, ALIF, OLIF, DLIF or MIDLF technique via a minimally invasive procedure and will receive the same medical treatment as if they would not participate in this study.

• The study will be monitored with visits conducted at the start, during and at the closure of the clinical study.
• MedDRA coding will be used to classify the Adverse Event.
• The study will be conducted according to Medtronic SOPs
• Sample size calculation: Assuming that the standard deviation for ODI improvement at 3 months is 20 for both groups (anterolateral and posterior) and there is no difference in the mean ODI improvement at 3 months, with 80% power and 5% alpha level, the sample size for the primary endpoint (DDD patients operated for spondylolisthesis) is as follows in order to claim equivalence between two groups with equivalent margin (-10, 10):
• Estimated sample size per group (anterolateral procedures versus posterior procedures): 70
• Estimated total sample size for spondylolisthesis patients: 140
• From the MASTERS-D study it is know that approximately 50% of the patients with degenerative disc disease have spondylolisthesis ≥ grade I. Hence the required total sample size is 140/0.5 = 280. The study is anticipated to enroll 350 patients.
• In addition to a final statistical analysis, 3 months and annual interim analyses are anticipated.
• The study hypothesis for the primary objective is to verify whether patients operated for spondylolisthesis (≥ grade I) have equivalent mean improvement of ODI at 3 months regardless of the minimally invasive surgical procedure (anterolateral or posterior) used.
• The null-hypothesis: Ho: Δ ODI_Anterolateral ≠ Δ ODI_posterior
• will be tested against the alternative hypothesis: HA: Δ ODI_Anterolateral = Δ ODI_posterior Where Δ ODI_Anterolateral is the average improvement in ODI score (baseline - 3 months) in spondylolisthesis subjects treated with the anterolateral approach and Δ ODI_posterior is the average improvement in ODI score (baseline - 3 months) in spondylolisthesis subjects treated with the posterior approach.

• Study Type: Observational
• Enrollment (Actual): 361

Contacts and Locations

Study Locations

• Argentina
  • Buenos Aires, Argentina, C1199ABD
    • Hospital Italiano de Buenos Aires
• Austria
  • Linz, Austria, 4020
    • Kepler Universitätsklinikum
• Belgium
  • Roeselare, Belgium, 8800
    • AZ Delta
• Brazil
  • Curitiba, Brazil, 80050-350
    • Hospital Universitario Cajuru
• China
  • Shanghai, China, 200072
    • Shangai Tenth People's Hospital
  • Liaoning
    • Dalian, Liaoning, China, 116011
      • The First Affiliated Hospital of Dalian Medical University
  • Sichuan
    • Chengdu, Sichuan, China, 610041
      • West China Hospital Sichuan University
• Czechia
  • Hradec Králové, Czechia, 500 05
    • Nový Hradec Králové
• Denmark
  • Glostrup Municipality, Denmark, 2600
    • Glostrup Hospital
• France
  • Eckbolsheim, France, 67201
    • Hôpital Civil de Strasbourg (NHC)
  • Lille, France, 59037
    • CHRU de Lille, Hôpital Roger Salengro
  • Marseille, France
    • Service de Neurochirurgie la Timone
• Germany
  • Magdeburg, Germany, 39130
    • Klinikum Magdeburg
• Italy
  • Milan, Italy, 20123
    • A.O. Fatebenefratelli e Oftalmico
• Mexico
  • Mexico City, Mexico, 4470
    • Hospital Naval General de Alta Especialidad
• Portugal
  • Braga, Portugal, 4710-243
    • Hospital Escala Braga
  • Porto, Portugal, 4200-319
    • Centro Hospitalar de São João
• Russia
  • Nizhny Novgorod, Russia, 603155
    • Nizhny Novgorod Research Institute of Traumatology and Orthopedics of Public Health Ministry
  • Novosibirsk, Russia, 630091
    • Scientific Research Institute of Traumatology and Orthopedics
• Slovakia
  • Bratislava, Slovakia, 82108
    • A-klinik
• South Korea
  • Ansan, South Korea, 425-707
    • Department of Orthopedics, Korea University Ansan Hospital
  • Gyeonggi-do, South Korea, 10444
    • National Health Insurance Corporation Ilsan Hospital
  • Seoul, South Korea, 156-755
    • Department of Neurological Surgery, Chung-Ang University Hospital
• Spain
  • Santander, Spain, 39008
    • Hospital Universitario Marques de Valdecilla
  • Valencia, Spain, 46026
    • Hospital L'Horta Manises
• United Kingdom
  • Hull, United Kingdom, HU3 2JZ
    • Hull Royal Infirmary
  • Ipswich, United Kingdom, IP45PD
    • East Suffolk and North Essex NHS Foundation Trust (was formerly Ipswich Hospital NHS)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

361 patients suffering from lumbar degenerative disc disease (DDD) were enrolled over a period of 42 months in 27 sites located in Europe, Latin America, and Asia Pacific.

Description

Inclusion Criteria:

• Patient is ≥ 18 years of age (or minimum age as required by local regulations)
• Patient has degenerative disc disease and an indication for a single or double level instrumented lumbar fusion for the treatment
• Patient agrees to participate in the study and is able to sign the Data Release Form/Informed Consent
• The procedure planned for the patient complies with the labeling of the Devices that may be used in the surgical procedure as described in the section Medical Devices of the Clinical Investigation Plan

• Patient is planned to be submitted to a minimally invasive fusion procedure using a posterior (PLIF, TLIF, MIDLF) or anterolateral (OLIF, ALIF, DLIF ) technique*

  *For a double level instrumented fusion, the same procedure must be used for both levels.

• The patient is willing and is able to perform study procedures and required follow-up visits.

Exclusion Criteria:

• Patient that has already undergone a lumbar fusion surgery
• Patient that has already undergone open lumbar surgery other than standard decompression surgery
• Indications for the procedure other than degenerative spine disease like: Osteoporotic vertebral fractures, Spine trauma fractures or Spine tumor
• Illiterate or vulnerable patients (e.g. minors, participants incapable of judgment or participants under tutelage)
• Concurrent participation in another clinical study that may confound study results.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Minimally invasive lumbar fusion; A single or double level instrumented fusion using minimally invasive PLIF, TLIF, MIDLF, DLIF, OLIF, ALIF procedures for the treatment of the degenerative lumbar spine.	Device: Minimally invasive lumbar fusion; Patients will receive a single or double level instrumented fusion using a minimally invasive/MAST™ PLIF, TLIF, DLIF, OLIF, ALIF or MIDLF surgical procedure with a posterior fixation. For the use of a posterior fixation system, the CD Horizon™ Spinal System, is mandatory in this study and will be either mini-open and/or percutaneous.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change (Preop-postop) of Disability, Oswestry Disability Index (ODI) at 3 Months as Compared to Baseline in DDD Patients With Spondylolisthesis	To demonstrate that DDD patients operated for spondylolisthesis fare equally well regardless of the surgical procedure (anterolateral or posterior) performed as measured by the change of ODI at 3 months as compared to baseline. ODI=Oswestry Disability Scale [0-100]; higher scores mean a worse outcome Timepoints: Baseline and 3 months	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse Events	Document Adverse Events occurrence throughout the study	Through 5 years
Change (Preop-postop) in Disability ODI as Compared to Baseline in DDD Patients Without Spondylolisthesis	To evaluate whether DDD patients without spondylolisthesis fare equally well regardless of the surgical procedure (anterolateral or posterior) performed, as measured by Oswestry Disability Index (ODI) at 3 months. Scored [0-100]; higher scores mean a worse outcome Timepoints: Baseline and 3 months	3 months
Change (Preop-postop) in ODI Scores for the Total Population	To observe the change in ODI scores as compared to baseline through 5 years. The score at baseline gives the baseline score [0-100]; the higher the score, the worse the outcome. Additional scores are based on the change from baseline. The higher the score, the greater the improvement. Timepoints: Baseline, 4 weeks, 3 months, 1-,2-,3-,4-, and 5-years	Through 5 years
Change (Preop-postop) in Visual Analog Scale (VAS) Back Pain Intensity	To observe a change in VAS back pain as compared to baseline through 5 years. At baseline scored on a scale from [0-10]; 0 = No pain 10= Worst pain possible. Timepoints: Baseline, 4 weeks, 3 months, 1-,2-,3-,4-, and 5-years	Through 5 years
Change (Preop-postop) in VAS Leg Pain Intensity	To observe the change in VAS leg pain as compared to baseline through 5 years. The score at baseline gives the baseline score [0-10]; 0 = No pain 10= Worst pain possible. Timepoints: Baseline, 4 weeks, 3 months, 1-,2-,3-,4-, and 5-years	Through 5 years
Change (Postop-preop) in EQ-5D Index Score	To observe the change in EuroQol-5 Dimension (EQ-5D) index score as compared to baseline through 5 years. Scored from [-0.109 to 1]. A higher score means a better outcome. Timepoints: Baseline, 4 weeks, 3 months, 1-,2-,3-,4-, and 5-years	Through 5 years
The Neurological Success Rate	Neurological status is based on four types of measurements (sections): motor, sensory, reflexes, and straight leg raising. Overall neurological success is defined as maintenance or improvement in all sections (motor, sensory, reflex, and straight leg raising) for the time period evaluated. In order for a section to be considered a success, each element in the section must remain the same or improve from the time of the baseline evaluation to the time period evaluated. Therefore, if any one element in any section does not stay the same or improve, then a patient was not considered a success for neurological status.	5 years
Fusion Success	Fusion success rate was summarized for at 1, 2, 3, 4, 5 year follow-up. If a participant showed fusion success at early time points and non-fusion at a later time point, the fusion status at all earlier points was considered as non-fusion. For 2-level fusion participants, fusion success was defined as achieving fusion at both treated levels.	Through 5 years
Proportion of Patients Needing a Secondary Spinal Surgery at the Index and/or Adjacent Level(s) (Reoperation Rates) Throughout the Study	To document Secondary Surgeries at index and/or adjacent level(s)throughout the study. When a participant requires additional surgery at the index level(s), it can be an indicator of insufficient outcomes of the initial surgery. Due to the progressive nature of the degenerative lumbar spine, additional surgeries at the index and/or adjacent levels might be required after the initial surgery. To ensure all safety and economic values are collected, the revision surgeries and their complication types and rates will be assessed during the study by the surgeons. For secondary surgery at index levels and/or secondary surgery at adjacent levels, survival analysis was performed to estimate the cumulative event rate up to 5 years.	Through 5 years
Amount of Days Needed for First Ambulation	To observe and document the days needed for participants to get out of bed and ambulate with or without assistance. Time range: [0-11] days	From surgery up to hospital discharge, up to 11 days
Amount of Days Needed to Recover From Surgery	To observe and document the days after the surgery, fulfilling following criteria: No need for intravenous infusion of analgesic drugs; No ongoing surgery related adverse events impending discharge; No need for nursing care Timeframe: [0-46] days The objective of the Surgery Recovery Day assessment is to collect the day when the participant could be discharged based on his actual clinical condition because the effective day of discharge may be prolonged by factors other than the participant's clinical recovery such as social factors or co-morbidity. For the purpose of reporting these parameters the day of the surgery were considered 'D0', the first day after surgery as 'D1', the second day as 'D2' and so on.	Surgery Recovery Day up to hospital discharge, with a maximum of 46 days
Healthcare Economics Evaluation "Medications"	Healthcare utilization were measured with the following three costs components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Baseline to 5-year follow-up
Health Economics Evaluation "Resources"	Healthcare utilization is measured with the following three cost components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Through 5 years
Health Economics Evaluation "Rehabilitation Program"	Healthcare utilization is measured with the following three costs components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Baseline to 5 years
Health Economics Evaluation "Operative Time"	Healthcare utilization is measured with the following three cost components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Peri-operative
Health Economics Evaluation "Estimated Blood Loss"	Healthcare utilization is measured with the following three cost components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Peri-operative
Health Economics Evaluation "Length of Hospital Stay"	Healthcare utilization is measured with the following three cost components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program The minimum-maximum time spent at the hospital was [1-53 days]	Post-operative, up to 53 days
Health Economics Evaluation "Total Fluoroscopy Time"	Healthcare utilization is measured with the following three cost components: resources: surgery room, length of hospital stay, additional medical visits (outpatient consultations, visits to primary care services, etc); medications; non-pharmacologic therapies: rehabilitation program	Peri-operative
To Observe and Document the Patient Profile When Choosing a Particular Minimally Invasive Fusion Procedure - Categorical Variables	To observe and document the patient profile when choosing a particular minimally invasive fusion procedure: Baseline information is summarized for all DDD patients per surgical procedure (ALIF, OLIF, DLIF, PLIF, TLIF, MIDLF).	Baseline
To Observe and Document the Patient Profile When Choosing a Particular Minimally Invasive Fusion Procedure - Age	To observe and document the patient profile when choosing a particular minimally invasive fusion procedure: Baseline information is summarized for all DDD patients per surgical procedure (ALIF, OLIF, DLIF, PLIF, TLIF, MIDLF).	Baseline
To Observe and Document the Patient Profile When Choosing a Particular Minimally Invasive Fusion Procedure - Height	To observe and document the patient profile when choosing a particular minimally invasive fusion procedure: Baseline information is summarized for all DDD patients per surgical procedure (ALIF, OLIF, DLIF, PLIF, TLIF, MIDLF).	Baseline
To Observe and Document the Patient Profile When Choosing a Particular Minimally Invasive Fusion Procedure - Weight	To observe and document the patient profile when choosing a particular minimally invasive fusion procedure: Baseline information is summarized for all DDD patients per surgical procedure (ALIF, OLIF, DLIF, PLIF, TLIF, MIDLF).	Baseline
To Observe and Document the Patient Profile When Choosing a Particular Minimally Invasive Fusion Procedure - BMI	To observe and document the patient profile when choosing a particular minimally invasive fusion procedure: Baseline information is summarized for all DDD patients per surgical procedure (ALIF, OLIF, DLIF, PLIF, TLIF, MIDLF).	Baseline

Collaborators and Investigators

• Sponsor: Medtronic Spinal and Biologics

Study record dates

Study Major Dates

• Study Start: December 1, 2015
• Primary Completion (Actual): November 10, 2019
• Study Completion (Actual): November 14, 2024

Study Registration Dates

• First Submitted: November 17, 2015
• First Submitted That Met QC Criteria: November 25, 2015
• First Posted (Estimated): December 1, 2015

Study Record Updates

• Last Update Posted (Actual): January 21, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Spinal Fusion; minimal invasive; spondylolisthesis; Lumbar fusion; CD Horizon® Spinal Systems; MAST procedure
• Additional Relevant MeSH Terms: Bone Diseases; Musculoskeletal Diseases; Spinal Diseases; Spondylolysis; Spondylosis; Spondylolisthesis; Intervertebral Disc Degeneration
• Other Study ID Numbers: P15-01