A Radiological Approach to Evaluate Bone Graft Integration in Reconstructive Surgeries

Bone Loss in Distal Radial Fractures Treated with A Composite Xenohybrid Bone Substitute: A Two Years Follow-Up Retrospective Study

(1) Background: Recently, surgical treatment of distal radius fractures has increased exponentially. Many locking plates' fixation systems have been developed allowing a more stable reduction and early mobilization. Sometimes, open reduction and fixation of distal radius fractures may leave a residual bone loss requiring grafting. This retrospective study reports clinical and radiologic outcomes of distal radius fractures treated with xenohybrid bone grafting in order to assess (i) the safety of the investigated bone graft; (ii) its radiological integration and biomechanical performances, and (iii) clinical outcomes of the patients; (2) Methods: We performed a retrospective study on a cohort of 19 patients. Preoperative X-ray and CT scan were performed. The mean clinical and radiographical follow-up was two years. Safety of the xenohybrid bone graft was constantly evaluated. Clinical results were assessed through the DASH score and Mayo wrist score; (3) Results: No adverse reactions, infections, and local or general complication were related to the use of xenohybrid bone graft. The radiolucency of the xenografts suggested progressive osteointegration. No evidence of bone graft resorption was detected. All the patients reached consolidation with good to excellent clinical results; and (4) Conclusions: Clinical and radiological data demonstrated that xenohybrid bone grafting promotes new bone formation and healing in osteopenic areas caused by fracture reduction.

Simulated Performance of a Xenohybrid Bone Graft (SmartBone®) in the Treatment of Acetabular Prosthetic Reconstruction

Total hip arthroplasty (THA) is a surgical procedure for the replacement of hip joints with artificial prostheses. Several approaches are currently employed in the treatment of this kind of defect. Overall, the most common method involves using a quite invasive metallic support (a Burch-Schneider ring). Moreover, valid alternatives and less invasive techniques still need to be supported by novel material development. In this work, we evaluated the performance of SmartBone®, a xenohybrid bone graft composed of a bovine bone matrix reinforced with biodegradable polymers and collagen, as an effective support in acetabular prosthesis reconstruction. Specifically, the material's mechanical properties were experimentally determined (E = ~1.25 GPa, Ef = ~0.34 GPa, and Et = ~0.49 GPa) and used for simulation of the hip joint system with a SmartBone® insert. Moreover, a comparison with a similar case treated with a Burch-Schneider ring was also conducted. It was found that it is possible to perform THA revision surgeries without the insertion of an invasive metal support and it can be nicely combined with SmartBone®'s osteointegration characteristics. The material can withstand the loads independently (σmax = ~12 MPa) or be supported by a thinner titanium plate in contact with the bone in the worst cases. This way, improved bone regeneration can be achieved.

Composite Xenohybrid Bovine Bone-Derived Scaffold as Bone Substitute for the Treatment of Tibial Plateau Fractures

Introduction: Tibial plateau fractures represent a common challenge for orthopaedic surgeons, sometimes representing complex cases to manage, where augmentation using bone grafts is required for stabilisation. Autologous iliac bone graft (AIBG) is the current gold standard for bone grafting. In order to overcome limitations related to the procedure, alternative strategies, like allogenic and xenogeneic bone substitutes have been investigated. Here, within the framework of an observational clinical study, we report clinical and radiological outcomes of patients treated for tibial plateau fractures with a composite xenohybrid bone graft, aiming at assessing clinical and radiological outcomes. Materials and Methods: We performed a cohort retrospective study of patients treated for tibial plateau fractures from May 2017 to January 2018. Thirty-four patients, i.e. 100% of those having received the bone graft under investigation for tibial plateaux fracture treatment, met the inclusion criteria and were enrolled in the study. Patients were assessed at 2 weeks, and then at a 1-, 3-, and 6-months, and 1-year follow-up. At each evaluation patients filled a visual analogue scale (VAS) for the level of pain during the day life activities and underwent physical exam and anteroposterior and lateral projection radiographs of the knee. At 1 year the Tegner Lysholm Scoring Scale, International Knee Document Committee 2000 (IKDC 2000), and Short Form (36) Health Survey (SF-36) were administered. Results: At 1-year, mean VAS decreased from 6.33 ± 1.40 to 1 ± 0.79 (P < 0.0001); Tegner Lysholm Scoring Scale was 89 ± 4.10 and mean IKDC 2000 was 78.67 ± 3.31. No infections, neurovascular complications or adverse effects related to implants were reported during the clinical exams at follow-up. Mean ROM was 124 ± 6°. Radiographs did not show defects of consolidation or progressive post-surgical subsidence and demonstrated a good grade of integration of the implant. Conclusions: Clinical and radiological outcomes, and scores of questionnaires, were good. The xenograft has demonstrated to be a safe biomaterial, with satisfactory mechanical and biological performances in the mid-term period. It also showed a high grade of osteointegration and remodelling.