Autologous bone grafting is a standard procedure for the clinical repair of skeletal defects, and good results have been obtained. Autologous vascularized bone grafting is currently the procedure of choice because of high osteogenic potential and resistance against reabsorption. Disadvantages of this procedure include limited availability of donor sites, clinical difficulty in handling, and a failure rate exceeding 10%. Allografts are often used for massive bone loss, but since only the marginal portion is newly vascularized after the implantation non healing fractures are often reported, along with a graft reabsorption. To overcome these problems, some studies in literature tried to conjugate bone graft and vascular supply, with encouraging results. On the other side, several studies in literature reported the ability of bone marrow derived cells to promote neo-vascularization. In fact, bone marrow contains not only hematopoietic stem cells (HSCs) and MSCs as a source for regenerating tissues but also accessory cells that support angiogenesis and vasculogenesis by producing several growth factors. In this scenario a new procedure was developed, consisting in an allogenic bone graft transplantation in a critical size defect in rabbit radius, plus a deviation at its inside of the median artery and vein with a supplement of autologous bone marrow concentrate on a collagen scaffold.

Twenty-four New Zealand male white rabbits (2500–3000 g) were divided into 2 groups, each consisting of 12 animals. Surgeries were performed as follow:

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Group 1 (#12): allogenic bone graft (left radius) / allogenic bone graft + vascular pedicle + autologous bone marrow concentrate (right radius)

For each group, 3 experimental time: 8, 4 and 2 weeks (4 animals for each time).

The bone used as graft was previously collected from an uncorrelated study. An in vitro evaluation of bone marrow concentrate was performed in all cases, and at the time of sacrifice histological and histomorphometrical assessment were performed with immunohistochemical assays for VEGF, CD31 e CD146 to highlight the presence of vessels and endothelial cells. Micro-CT Analysis with quantitative bone evaluation was performed in all cases.

The bone marrow concentrate showed a marked capability to differentiate into osteogenic, chondrogenic and agipogenic lineages. No complications such as infection or intolerance to the procedure were reported. The bone grafts showed only a partial integration, mainly at the extremities in the group with vascular and bone marrow concentrate supplement, with a good and healthy residual bone. immunohistochemistry showed an interesting higher VEGF expression in the same group. Micro CT analysis showed a higher remodeling activities in the groups treated with vascular supplement, with an area of integration at the extremities increasing with the extension of the sacrifice time.

The present study suggests that the vascular and marrow cells supplement may positively influence the neoangiogenesis and the neovascularization of the homologous bone graft. A longer time of follow up and improvement of the surgical technique are required to validate the procedure.

Introduction

Multiple ACL revisions represent an extremely demanding surgery, due to the presence of enlarged or malpositioned tunnels, hardware, injuries to the secondary stabilizers and difficulties in retrieving autologous tendons. An anatomical ACL reconstruction is not always possible. We analyzed the results in a series of patients operated with over the top reconstruction (OTTR) and lateral extra-articular plasty to the Gerdy's tubercle (LP) using Achilles (AT) or tibialis posterior tendon (TPT) allografts.

Osteocondritis dissecans (OCD) is a relatively common cause of knee pain. Ideal treatment is still controversial. Aim of this exhibit is to describe the outcomes of 5 different surgical techniques in a series of 63 patients.

63patients (age 22.5±7.4 years) affected by OCD of the femoral condyle (45 medial and 17 lateral) were treated by either osteochondral autologous transplantation, autologous chondrocyte implantation with bone graft, biomimetic nanostructured osteochondral scaffold (Maioregen) implantation, bone-cartilage paste graft or bone marrow derived cells transplantation “one-step” technique. Patient evaluation included IKDC score, eq-vas score, X-Rays and MRI preoperatively and at follow-up.

Global mean IKDC improved from pre-operative 40.1±14.6 to 77.2±21.3 (p<0.0005) at mean 5.3±4.7 years follow-up, while eq-vas improved from 51.7±17.0 to 83.5±18.3(p<0.0005). No influence of age, size of the lesion, length of follow-up and associated surgeries on the result was found. No differences were found between the results obtained with different surgeries except a slight tendency of better improvement in the result following autologous chondrocyte implantation (p<0.01). Control MRI evidenced a satisfactory repair of cartilaginous layer and subchondral bone.

The techniques described were effective in providing good clinical and radiographic results in the treatment of OCD and confirmed the validity of autologous chondrocyte implantation over time. Newer techniques such as Maioregen implantation and “one-step” base on different rationales, the first relying on the characteristics of the scaffold and the second on the regenerative potential of mesenchymal cells. Both of them have the advantages to be minimally invasive surgeries and to require a single operation.

INTRODUCTION

Fresh bipolar shell osteochondral allograft (FBOA) is a controversial treatment option for post-traumatic ankle arthritis. Immunological response to transplanted cartilage may play a role in failure. Aim of the study is to compare two groups of patients who received FBOA in association or not to immunosuppressive therapy.

Introduction: Ideal treatment of osteochondral lesions of the talus (OLT) is still controversial.

Aim of this study is to review the 10 years follow-up clinical and MRI results of open field Autologous Chondrocytes Implantation in the treatment of OLT.

Methods: From December 1997 to November 1999, 10 patients, age 25.8 +/−6.4 years, affected by OLT, received open field Autologous Chondrocytes Implantation. The mean size of the lesions was 3.1 cm² (2.2 – 4.3).

All patients were evaluated clinically (AOFAS score), radiographically and by MRI pre-operatively and at established intervals up to a mean follow-up of 119+/−6.5 months. At the final follow-up MRI T2 mapping evaluation was performed. A bioptic sample was harvested in 5 cases during hardware removal 12 months after implantation.

Results: Before surgery the mean score was 37.9 +/−17.8 points, at 24 months it was 93.9 +/−8.5, while at final follow-up it was 92.7 +/−9.9 (p< 0.0005).

Bioptic samples showed cartilaginous features at various degrees of remodelling, positivity for collagen type II and for proteoglycans expression. No degenerative changes of the joint at follow-up were found radiographically.

MRI showed well-modelled restoration of the articular surface. The regenerated cartilage showed a mean T2 mapping value of 46 msec with no significant difference compared to that of normal hyaline cartilage.

Conclusions: The clinical and histological results have confirmed the validity of the technique utilized with a durability of the results over time. T2 mapping was adequate in detecting the quality of the regenerated tissue coherently with the bioptic results.

Introduction: Qualitative evaluation of postoperative outcome in cartilage repair techniques is an issue due to morbidity of bioptic second look. T2 mapping is becoming increasingly popular in the knee, providing information about the histological and biochemical contents of healthy or reparative tissue. Nevertheless, little is known about its applicability to the ankle due to thinner cartilage layer.

Aim of this study was to investigate the validity of T2 mapping in ankle cartilage characterization.

Materials and Methods: 20 healthy volunteers and 30 patients affected by osteochondral lesions of the talus and previously treated by different cartilage repair techniques, were evaluated by T2 mapping. Reparative procedures included microfractures, Autologous Chondrocyte Implantation (open or arthroscopic) and Bone Marrow Derived Cell’s Transplantation. DPFSE with or without fat suppression, T2FSE with or without fat suppression, 3D SPGR and T2-Mapping using a dedicated phased array coil and 1.5 T MR scanner were used as MRI acquisition protocol.

MRI results were correlated with clinical score (AOFAS) in the cases who received a cartilage reconstruction treatment.

Results: A statistically significant correlation (p< 0.05) was shown between MRI and clinical results. A reduced mean T2 value, suggestive for fibrocartilage features, was shown at repair sites in microfractures, whereas no significative differences with healthy hyaline cartilage mean T2 value, were found in other repair techniques with good to excellent clinical score.

Conclusions: T2 mapping demonstrated to be adequate in characterizing cartilage tissue in the ankle. Further studies are required to implement a tool which may over time be a valuable non-invasive alternative to bioptic evaluation.

Introduction: In situ subtalar arthrodesis cannot restore anatomical shape of the hindfoot in severe flat foot deformities. Purpose of this paper is to evaluate the result of 250 feet consecutively operated by subtalar arthrodesis with distraction and insertion of a mini structural bone block (SAMBB).

Material and Methods: 178 patients (250 feet), mean age 55+/−11 years affected by acquired adult flat foot with subtalar arthritis were evaluated clinically and radiographically and selected to receive SAMBB.

Arthrodesis was performed through a 2.5 cm incision, with partial cartilage removal and insertion of a structural corticocancellous block (2 × 1cm), harvested from the proximal ipsilateral tibia, vertically positioned into the sinus tarsi. Associate procedures were Achilles tendon lengthening (124), SERI procedure (61), hind-foot deformity correction (32). Postoperatively plaster-cast without weight-bearing for 4 weeks followed by walking boot was advised. All patients were reviewed at a minimum follow-up of 5 years.

Results: Before surgery the mean AOFAS score was 42+/−15, while it was 90+/−8 at follow-up (p< 0.005). Mean heel valgus deviation at rest was 15°+/−8° preoperatively and 6°+/−5° at follow-up (p< 0.005). Mean angulation of Meary’s line at talonavicular joint level was 160°+/−11° preoperatively and 174°+/−8 at follow-up. No complications were found. No or minimal arthritis progression was observed in the ipsilateral foot joints at follow up.

Conclusions: SAMBB resulted in an adequate correction of the deformity, with restoration of the anatomical shape of the hind foot and correction of the relationship with the midtarsal joint with no need of hardware. Consequent reduced arthritis progression and excellent clinical result were obtained.

Objective: Different

Methods: have been proposed to date to achieve the regeneration of hyaline cartilage in osteochondral lesions of the talus (OLT). The aim of this study was to present a new one-step arthroscopic procedure with the use of mesenchimal stem cells (MSC) supported on a collagen scaffold and Platelet Rich Fibrin (PRF).

Methods: 14 patients with a diagnosis of OLT underwent this procedure. The MSC were harvested from the posterior iliac crest and concentrated directly in the operating room. An ankle arthroscopy was performed with lesion detection and curettage. The cell concentrate was mixed with a collagen paste as scaffold and with PRF as a pool of growth factors in order to have a final composite to fill the lesion site. Partial weight bearing for 2 months and early ROM was advised postoperatively.

Results: According to the American Orthopaedic Foot and Ankle Score (AOFAS) system the patients had a preoperative score of 65.1 (range 35–79), a postoperative of 69.4 (range 61–97) at 6 months and of 83.6 (range 65–100) at 12 months follow up. MRI control at 6 and 12 months showed a progression of the reparative process in the osteochondral lesions. Histological and immuno-hystochemical analysis on a sample biopsed during a control arthroscopy at 12 months confirmed the hyaline quality of the regenerated cartilage.

Conclusions: This one-step technique demonstrated to be capable to regenerate hyaline cartilage, with the advantages of a reduced surgical time, lower costs and lower patient’s morbidity.