GreenBRIC Clinical Trial (GreenBRIC)

A Pre-Market Multicenter National Open Label Single Arm Study to Evaluate the Safety and Performance of a Class III Medical Device (Greenbone Implant) for Iliac Crest Reconstruction Following Bone Graft Harvesting for Pelvic Fusion.

This is a multi-centre, prospective, open-label, single-arm, first-in-man clinical investigation. The patients enrolled in this clinical trial will undergo elective surgery for pelvic fusion. Following harvesting of autologous bone graft form the iliac crest, the donor site will be reconstructed with a new scaffold known as GreenBone. GreenBone is a ceramic reabsorbable scaffold which is obtained by the transformation of wood. It has a very similar structure to bone. The aim of the study is to evaluate the safety of using the GreenBone in humans and also to evaluate its capacity to promote new bone formation at the donor site.

Bone defects can result from high-energy traumatic events, bone resection due to different pathologies such as tumors or infection, or from the treatment of complex non-unions, all very challenging conditions in orthopaedic practice. Defects of pelvic iliac crest most frequently result from harvesting of iliac bone graft for bone grafting and fusion procedures and can be associated with significant morbidity. Current reconstruction options of the bone defects usually imply the use of bone grafts and/or biocompatible materials, to create a scaffold that bridges the defect, favouring the migration of cells from the neighbouring tissues to fill the gap. Autografts and allografts are the most commonly used bone grafts currently used for large bone defects. However, the use of both types of grafts has significant disadvantages. For iliac crest reconstruction in particular, different types of synthetic materials and xenografts have been used. However, at the moment, there is not any ideal bone substitute with the necessary osteoinductive, osteoconductive and mechanical properties. GreenBone is a synthetic, acellular, reabsorbable, new generation bone graft, being suitable for surgical reconstruction of bone defects. When autologous bone graft is needed for the treatment of non-unions or bone defects, it is harvested from the pelvic iliac crest in the form of either tricortical graft material or cancellous bone. Harvested tricortical graft blocks are used to facilitate fusion of joints (i.e. pubis symphysis, sacroiliac joint), to structurally support metaphyseal areas of articular impaction injuries (i.e. tibial plateau) and to fill in metaphyseal bone voids. The GreenBone device, with its inherent physical and biomimetic properties, possesses similar structural properties to bone, and thus, it can be considered the ideal bone graft. Reconstruction of the donor site restores the pelvic anatomy and minimises the risk of chronic pain, haematoma formation and herniation of the abdominal contents. The purpose of this study is to assess the safety of the use of GreenBone in patients undergoing iliac crest reconstruction to restore bone defects. In particular, this study will evaluate the progression of bone healing and regeneration of the donor site throughout a 6-month observation period, it will evaluate the postoperative pain related to iliac crest graft harvesting, and it will evaluate the health related quality of life of patients at 6 months. Patient who will be enrolled in the study will receive exactly the same operation that they would receive normally for pelvic fusion with the only difference that instead of having xenograft (bone obtained from cows) applied to the donor site (the site in your pelvis from where the surgeon will harvest the bone graft), you will receive the GreenBone material. Following surgery patients will be followed-up for 6 months. At each follow-up visit, the safety of the use of the GreenBone implant will be assessed and patients will complete a pain-scale and quality of life questionnaires. Moreover, incorporation of the Bone graft into the iliac crest will be assessed radiologically.

Patients will receive the GreenBone implant instead of bovine xenograft for iliac crest reconstruction following autologous bone graft harvesting.

Evaluation of adverse events during the study period. All adverse occurrences (serious/non-serious or device related/non-device related) will be recorded prospectively, categorized and evaluated for causality using defined criteria.

Evaluation of the bone regeneration in the area of intervention, by means of X-ray examination by an independent radiologist; X-ray scoring systems have been implemented according to the criteria proposed by Lane and Sandhu (bone formation, union and remodelling). Score 0 indicates no signs of healing while max score 10 indicates complete healing/incorporation of the graft.

Evaluation of degree of pain perceived by the patient, by means of a VAS (Visual Analogue Scale) (0-100 mm), on every visit.

Evaluation of Quality of Life by means of a validated EuroQol (EQ-5D) questionnaire administered at every follow-up visit.

Inclusion Criteria: Patients requiring iliac crest reconstruction secondary to pelvic fusion Patients understanding the nature of the study and providing their informed consent to participation Patient is considered able to complete the study assessment and visit schedule in the opinion of the investigating team. Exclusion Criteria: Patients with bone infections at the time of enrolment. Patients with bone malignant tumor(s) at the time of enrolment. Patients who have been treated with chemotherapy or radiotherapy within 12 months before the study enrolment. Patients with concomitant infectious systemic diseases at the time of enrolment. Patients with known inflammatory systemic diseases at the time of enrolment. Patients with concomitant myeloproliferative disorders at the time of enrolment. Patients currently treated with systemic immunosuppressive agents, including steroids. Patients with active autoimmune disease. Patients with coagulopathy or bleeding disorders. Patients who have received a previous treatment of bone substitution in the same anatomical site. Patients with known or suspected allergy or hypersensitivity to the GreenBone Implant components. Patients who are participating or have participated in other clinical studies within the 30 days before the study enrolment. Pregnant women and/or women that intend to be pregnant within 6 months from surgery.