Efficacy and Safety Study of Non-percutaneous Vertebroplasty With Macroporous Calcium Phosphate Cement (MCPC)
Condition: Vertebra Trauma
Study type: Interventional
Phase: Phase 2

Summary: 
      The macroporous calcium phosphate cement, MCPC, which composition is close to bone, is
      malleable and biocompatible, and has intrinsic radio opacity and good ability to undergo
      mechanical constraints. After the filling of the bone cavity, the cement hardens.
      Interestingly, this calcium phosphate cement has no exothermic hardening (on the contrary,
      the ordinary cements used nowadays cause necrotic lesions in tissues around during this
      phase) and favours vascularisation, cellular colonisation and bone healing. Thanks to its
      resorbability, the MCPC cement is replaced little by little by a physiologic bone. This last
      property is very important for young people needing a vertebroplasty after a traumatism.

      Thus, it will be tested in a low-invasive surgery, a non-percutaneous vertebroplasty,
      consisting in filling with the MCPC the body of the broken vertebra, after its stabilization
      thanks to 4 interpedicular screws. This protocol will be proposed to patients 1 to 3 weeks
      after the trauma having caused the fracture.

      The follow up will last 12 months with 5 visits (2 days, and 3, 4, 6 and 12 months after
      vertebroplasty), 2 CT scanners before inclusion and at 12 months, 2 EOS (ultra low dose
      imager replacing classical radiography) at 5 and 12 months, questionnaires (visual analogic
      scale for pain, and quality of life with OSWESTRY and SF36 scales) before inclusion and at 2
      days, and 3, 4, 6 and 12 months, and biological exams (CRP/VS, for inflammation) at each
      visit except 2 days after surgery. An osteodensitometry will be performed at 3 months.
    

Detailed description: 
      The macroporous calcium phosphate cement, MCPC, which composition is closer to bone than
      acrylic cement, is malleable and biocompatible, and has intrinsic radio opacity and good
      biomechanical properties (12 +/- 3 Mpa in 24 hours). After the filling of the bone cavity,
      the cement hardens in situ thanks to hydrolysis and apatite precipitation. Interestingly,
      this calcium phosphate cement has no exothermic hardening (on the contrary, the PMMA causes
      necrotic lesions in tissues around during this phase). During the dissolution, a
      macroporosity takes form between biphasic calcium phosphate granules. That permits
      vascularisation, cellular colonisation and bone healing. Thanks to its resorbability, the
      MCPC cement is replaced by a physiologic tissue. This last property is very important for
      young people needing a vertebroplasty after a traumatism.

      The issue is to validate this biomaterial with appropriate mechanical, biocompatibility
      properties and intrinsic radio opacity, and that can favour bone regeneration, with a lower
      frequency of leak and risk enhancement of other vertebra fracture. The MCPC will thus be
      tested on few patients to assess its efficacy and security for bone filling in vertebra site.

      Thus, it will be used in a low-invasive surgery, a non-percutaneous vertebroplasty,
      consisting in filling with the MCPC the body of the broken vertebra, after its stabilization
      thanks to 4 interpedicular screws. This protocol will be proposed to 21 patients 1 to 3 weeks
      after the trauma having caused the fracture. The follow up will last 12 months with 5 visits.
    

Intervention name(s): non percutaneous vertebroplasty
Intervention type(s): Procedure
Intervention description(s): The patient will undergo general anaesthetic. With a low invasive approach, 4 screws will be placed in pedicles of vertebra under and above the fractured vertebra. The reduction of the fracture will be realised by a smooth movement, and screws positions will be verified by a radio control, with a guided navigation system. The stems will be placed and locked. After the screw positioning, the fractured vertebra pedicles will be reached by a low invasive approach, using a 6 mm trocar, to raise, if necessary, the vertebral plate. Then the cement will be injected in the vertebral body, under radio control. When the maximal volume (6 to 8 ml) is reached, or if an extra vertebral leak is detected, the cement injection is stopped. Then the incision is closed. The next day, the patient will be placed in a corset for a 2 months period.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Vertebroplasty; spine; vertebra height; adverse events; calcium phosphate bone cement