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Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_II | Pages 268 - 268
1 May 2009
Buda R Di Caprio F Fornasari P Giannini S
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Aims: This work analyzed the effects of storage by fresh-freezing at −80°C on the histological, structural and biomechanical properties of the human posterior tibial tendon (PTT), used for ACL reconstruction.

Methods: Twenty-two PTTs were harvested from eleven donors. For each donor one tendon was frozen at −80°C and thawed in physiologic solution at 37°C, and the other was tested without freezing (control). Transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and biomechanical analysis were performed.

Results: We found the following mean changes in frozen-thawed tendons compared to controls: TEM showed an increase in the mean diameter of collagen fibrils and in fibril non-occupation mean ratio, while the mean number of fibrils decreased; DSC showed a decrease in mean denaturation temperature and denaturation enthalpy. Biomechanical analysis showed a decrease in ultimate load and ultimate stress, an increase in stiffness and a decrease in ultimate strain of tendons.

Conclusions: Fresh-freezing brings about significant changes in the biomechanical and structural properties of the human PTT. A high variability exists in the biophysical properties of tendons among individuals and in the effects of storage on tendons. Particular care is required when choosing an allograft tendon and further studies are required to clarify the role of donors’ age and sex, and other factors, in determining the suitability of an allogenic tendon. The future directions could be:

(a) To choose the tendon grafts considering the donors’ characters;

(b) To use fresh tendons;

(c) To test the controlateral tendon from the same donor before use.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_III | Pages 429 - 429
1 Oct 2006
Dallari D Stagni C Cenacchi A Savarino L Fornasari P Giunti A
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Aim: To assess the effect of lyophilised bone grafts, autologous platelet gel and autologous medullary cells on bone repair processes after tibial osteotomy for genu varum

Methods: Thirty patients, divided into 3 groups by the generation of random sampling numbers, were treated by valgus osteotomy for genu varum with a minimum correction of 8 mm and fixation using a titanium plate (TITAN plate® Citieffe).

The groups were thus divided:

Group 1: lyophilised bone chips.

Group 2: lyophilised bone chips + platelet gel

Group 3: lyophilised bone chips + platelet gel + packed autologous medullary cells (Buffy coat).

At six weeks X-rays, MRI and needle biopsies were carried out. The tissue underwent morphological and microstructural tests.

Results confirmed that the use of platelet gel and packed medullary cells as adjuvant for the lyophilised bone aid bone repair and graft integration. Morphological and morphometric tests showed that at six week the newly formed bone of group 3 had better mechanical properties.

Conclusions: This study shows that the use of platelet gel and packed autologous medullary cells combined with lyophilised bone chips produces a faster and mechanically stronger recovery of bone stock in the treatment of bone defects.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_II | Pages 182 - 183
1 Apr 2005
Greggi T Giacomini S Di Silvestre M Bassi A Fornasari P Parisini P
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Homoplastic bone has been produced and used at the Rizzoli Orthopaedic Institute since 1998. Bone grafts are treated following the “freeze-dry” technique developed by the Rizzoli Bone Bank. Up to now, 111 patients have been surgically managed by using lyophilised bone grafts at the Division of Spine Surgery.

With a follow-up of more than 12 months, the authors reviewed 81 subjects affected with scoliosis (45 cases – group A), lumbar diseases (34 cases – group B) and segmental cervical degenerative stenosis (two cases – group C). Group A consisted of 20 patients, mean age 14 years, affected with progressive or congenital idiopathic scoliosis; 12 patients, mean age 34.5 years, affected with adult symptomatic scoliosis; 10 patients, mean age 14.4 years, affected with neuromuscular scoliosis; and the remaining three, mean age 37 years, who had already undergone surgery) presenting with pseudarthrosis. Surgical technique was circumferential arthrodesis in paediatric congenital scoliosis and posterior arthrodesis in adult and adolescent idiopathic scoliosis. Fusion was extended to the sacrum and iliac crests in five cases of neuromuscular scoliosis. Patients of group B (16 spondylolisthesis and 18 degenerative lumbar instability), aged 42 years on average, underwent posterior arthrodesis with pedicle fixation. Only two patients in group C were treated with bone graft anteriorly placed at the cervical level to supplement the intersomatic fusion with cage. At a mean follow-up of 28 months, solid fusion was observed in 79 cases (97%); a clearly visible pseudarthrosis was seen only in two cases (3%) (an infantile scoliosis and reintervention for neuromuscular scoliosis in an adult patient). A deep infection with Staphlylococcus aureus was encountered in one patient (1.2%) with degenerative lumbar instability treated with arthrodesis and L2-S1 pedicle fusion: the infection resolved after surgical reintervention (leaving the instrumentation in situ) and drainage.

Lyophilised bone, either used as wedge grafts anteriorly or morcellised grafts posteriorly, provides good resistance and integration. Safety, ready availability and possibility to be stored at environmental temperature are further advantages offered by these bone grafts, which make them particularly suitable for application in spinal surgery, above all when surgical times are long and the risk of complications is high.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 68 - 68
1 Mar 2005
Dallari D Stagni C Cenacchi A Savarino L Fornasari P Giunti A
Full Access

Aim: to assess the effect of lyophilized bone grafts, autologous platelet gel and autologous medullary cells on bone repair processes after tibial osteotomy for genu varum.

Methods: thirty patients, divided into 3 groups by the generation of random sampling numbers, were treated by valgus osteotomy for genu varum with a minimum correction of 8 mm and fixation using a titanium plate (TITAN plateA8 Citieffe).

The groups were thus divided:

Group 1: lyophilized bone chips.

Group 2: lyophilized bone chips + platelet gel

Group 3 lyophilized bone chips + platelet gel + packed autologous medullary cells (buffy coat).

At six weeks X-rays, MRI and needle biopsies were carried out. The tissue underwent morphological and microstructural tests.

Results: preliminary results confirmed that the use of platelet gel and packed medullary cells as adjuvant for the lyophilized bone aid bone repair and graft integration. Morphological and morphometric tests showed that at six week the newly formed bone of group 3 had better mechanical properties.

Conclusions: this study shows that the use of platelet gel and packed autologous medullary cells combined with lyophilized bone chips produces a faster and mechanically stronger recovery of bone stock in the treatment of bone defects.