Radiological and Clinical Efficacy of a Hybrid Spinal Implant ("Topping Off"): a Mono-center, Prospective Clinical Trial

The Use of the DTO Hybrid Dynamic Device: a Clinical Outcome- and Radiological-based Prospective Clinical Trial

The study aim is to show the effectiveness of a hybrid system (DTO) regarding clinical outcome and radiological alteration in a single-center prospective setting.

Posterior spondylodesis and monosegmental intervertebral cage plus flexible instrumentation of the superiorly adjacent segment (Dynesys DTO).

Planned follow-up visits up to 48 months with documentation of health-related outcome measurement instruments and radiological control of possible segment alteration and device-related complication.

Inclusion Criteria:

• Informed consent
• Legal capacity
• Age ≥ 18 years
• Indication for monosegmental lumbar spine fusion (PLIF or "topping-off ") L2-S1 with osteochondrosis Modic grades I-III or spondylolisthesis Meyerding grades I-III.
• Radiologic signs of degeneration in the adjacent segment of the intended fusion without signs of instability

Exclusion Criteria:

• Motor deficit
• Cauda equina syndrome
• Previous surgical intervention of the lumbar spine
• Relevant peripheral neuropathy
• Acute denervation subsequent to a radiculopathy
• Scoliosis with Cobb angle greater than 25°
• Spondylolisthesis > Meyerding grade III
• Radiologic signs of degeneration in the adjacent segment of the intended fusion with signs of instability (for definition, see inclusion criteria)
• No radiologic signs of degeneration in the adjacent segment of the intended fusion (for definition, see inclusion criteria)
• Radiologic signs of degeneration in the adjacent segment of the intended fusion with >Fujiwara grade II or >Pfirrmann grade IV
• Signs of instability in any lumbar spine segment other than that undergoing fusion
• General contraindication for elective lumbar spine surgery
• Pathologic fracture
• Osteoporosis with pathologic fracture
• Active systemic infection
• Rheumatic disease
• Disease of bone metabolism (e.g. Paget's Disease)
• Bone metastasis
• Local infection focus lumbar spine
• Seizure disorder
• Chronic ischemia Fontaine classification IIb-IV
• Severe heart insufficiency (NYHA III-IV)
• Blood coagulation disorder or blood thinning therapy
• Cortisone intake more than one month in the last 12 months before randomization
• Simultaneous participation in another clinical trial in the 30 days before randomization
• Known allergy or intolerance to the implants
• Dependency on investigator
• Lack of familiarity with the German language
• Placement in an institution by governmental or juridical advice
• Absent legal capacity
• Pregnancy