Francesco Di Caprio

Arthroscopic Autologous Chondrocyte Implantation in Osteochondral Lesions of the Talus : Surgical Technique and Results

Background Autologous chondrocyte implantation (ACI) in the ankle was considered up to now an extremely technically demanding surgery with considerable morbidity for the patients. Hypothesis Hyalograft C scaffold allows arthroscopic ACI, thanks to a specifically designed instrumentation. Study Design Case series; Level of evidence, 4. Methods Forty-six patients with a mean age of 31.4 years (range, 20–47) underwent operation from 2001 to 2004. They had posttraumatic talar dome lesions, type II or IIA. In the first step of surgery, an ankle arthroscopy was performed, with cartilage harvest from the detached osteochondral fragment or from the margins of the lesion. Chondrocytes were cultured on a Hyalograft C scaffold. In the second step of surgery, the Hyalograft C patch was arthroscopically implanted into the lesion, with a specifically designed instrumentation. Lesions >5 mm deep were first filled with autologous cancellous bone. Patients were evaluated clinically with the American Orthopaedic Foot and Ankle Society (AOFAS) score preoperatively and at 12 and 36 months after surgery. At a mean time interval of 18 months, the first 3 patients underwent a second-look arthroscopy with cartilage harvest from the implant and histological examination. Results The mean preoperative AOFAS score was 57.2 ± 14.3. At the 12-month follow-up, the mean AOFAS score was 86.8 ± 13.4 (P < .0005), while at 36 months after surgery, the mean score was 89.5 ± 13.4 (P < .0005). Clinical results were significantly related to the age of patients and to previous operations for cartilage repair. The results of the histological examinations revealed hyaline-like cartilage regeneration. Conclusions The Hyalograft C scaffold and the specifically designed instrumentation allowed arthroscopic implantation of chondrocytes, with excellent clinical and histological results.

Autologous chondrocyte implantation in the knee joint: open compared with arthroscopic technique. Comparison at a minimum follow-up of five years.

Autologous chondrocyte implantation is a widely used technique for treating cartilage lesions1-10. The technique, first introduced and described by Brittberg et al. in 199411, required an arthrotomy of the joint, debridement of the lesions, and the suturing of a periosteal flap to create a pocket to host the chondrocytes. Autologous chondrocyte implantation in the knee joint has provided hyaline-like repair tissue11-16, with satisfactory clinical results in 80% to 90% of patients1,7,17. Moreover, autologous chondrocyte implantation has been shown to be a valid alternative to the mosaicplasty and microfracture repair techniques used in the treatment of osteochondral lesions of the knee1,6,13,17-20. In the recent past, to simplify the autologous chondrocyte implantation surgical technique, a three-dimensional hyaluronic acid scaffold was developed to support the autologous chondrocytes13. This scaffold enables an arthroscopic implantation technique to be used21. Furthermore, the chondrocytes embedded on the hyaluronic acid scaffold tend to maintain their original phenotype22 with respect to dedifferentiation induced by the fluid medium23. Despite initial encouraging results with the use of arthroscopic autologous chondrocyte implantation in the treatment of osteochondral lesions of the knee24-26, open and arthroscopic autologous chondrocyte implantation techniques have been compared in only a few studies23,25,26, and these have included only short-term follow-up and limited and nonhomogeneous case series. The aim of this study was to compare the long-term results in two groups of patients in whom osteochondral lesions in the knee joint were treated with the two aforementioned procedures. Patients were evaluated clinically, histologically, and with magnetic resonance imaging, with a minimum five-year follow-up. Between 1997 and 2002, …

Effects of freezing on the biomechanical and structural properties of human posterior tibial tendons

This work analyzes 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. Twenty-two PTTs were harvested from eleven donors. For each donor one tendon was frozen at −80°C and thawed in physiological 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. 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. In conclusion 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. Therefore, when choosing an allograft tendon, particular care is needed to choose a biomechanically suitable graft.RésuméCe travail a pour but d’analyser les effets du stockage à −80°C sur le plan histologique, structurel et biomécanique d’un tendon le tibial ou jambier postérieur (PTT), utilisé pour la reconstruction des ligaments croisés antérieurs. 22 PTT ont été conservées provenant de 11 donneurs. Pour chaque donneur un tendon a été congelé à −80°C et l’autre, conservé dans une solution physiologique à 37°C. Ces tendons ont été testés. L’examen par microscope électronique (TEM), le scanner calorimétrique (DSC) et une analyse biomécanique ont été réalisés. Nous avons trouvé des changements dans les tendons conservés au froid en comparaison du groupe contrôle. Le TEM, examen au microscope électronique a montré une diminution du diamètre des fibres collagènes. L’analyse biomécanique a montré également une diminution de la résistance à la charge et au stress ainsi qu’une augmentation de la rigidité et une diminution des contraintes terminales au niveau du tendon. En conclusion: la congélation des tendons frais amène des modifications significatives des caractéristiques biomécaniques et structurelles du tendon PTT humain. Il existe une variation importante des propriétés biophysiques des tendons parmi les individus et du fait de leurs conservations. Pour cela, il est nécessaire lorsque l’on choisit un tendon et une allogreffe du tendon d’apporter dans le choix sur le plan biomécanique un soin particulier.

Bipolar Fresh Osteochondral Allograft of the Ankle

Background: Severe post-traumatic ankle arthritis poses a reconstructive challenge in the young and active patient. Bipolar fresh osteochondral allograft (BFOA) may represent an intriguing alternative to arthrodesis and prosthetic replacement. The aim of this study was to describe a lateral trans-malleolar technique for BFOA, and to evaluate the results in a case series. Materials and Methods: From 2004 to 2006, 32 patients, mean age of 36.8 ± 8.4 years, affected by ankle arthritis underwent BFOA with a mean followup of 31.2 months. The graft was prepared by specifically designed jigs, including the talus and the tibia with the medial malleolus. The host surfaces were prepared by the same jigs through a lateral approach. The graft was placed and fixed with twist-off screws. Patients were evaluated clinically and radiographically at 2, 4, and 6 month after operation, and at a minimum 24 months followup. A biopsy of the grafted areas was obtained from 7 patients at 1-year followup for histological and immunohistochemical examination. Results: Preoperative AOFAS score was 33.1 ± 10.9 and postoperatively 69.5 ± 19.4 (p < 0.0005). Six failures occurred. Cartilage harvests showed hyaline-like histology with a normal collagen component but low proteoglycan presence and a disorganized structure. Samples were positive for MMP-1, MMP-13 and Capsase-3. Conclusion: The use of BFOA represents an intriguing alternative to arthrodesis or arthroplasty. We believe precise allograft sizing, stable fitting and fixation and delayed weightbearing were key factors for a successful outcome. Further research regarding the immunological behavior of transplanted cartilage is needed. Level of Evidence: IV, Retrospective Case Series

Allograft Salvage Procedure in Multiple-Revision Anterior Cruciate Ligament Reconstruction

Background: Multiple-revision anterior cruciate ligament (ACL) reconstructions represent a surgical challenge due to the presence of previous tunnels, hardware, injuries to the secondary stabilizers, and difficulties in retrieving autologous tendons. An anatomic ACL reconstruction may therefore result in a demanding surgery, thus requiring 2 stages. Purpose: To analyze the efficacy of an over-the-top ACL reconstruction technique plus extra-articular plasty using Achilles or tibialis posterior tendon allograft in restoring knee stability in patients with at least 2 failed previous ACL reconstructions, as well as to evaluate the factors able to affect the final outcome. Study Design: Case series; Level of evidence, 4. Methods: From 2002 to 2008, 24 male athletes with a mean age of 30.8 years underwent surgery. Twenty patients had undergone 2, whereas 4 patients had undergone 3 previous reconstructions. The International Knee Documentation Committee (IKDC) score and KT-2000 arthrometric evaluation were used to measure outcomes at a mean follow-up period of 3.3 years (range, 2-7). Results: The mean ± SD IKDC subjective score at follow-up was 81.3 ± 14.0. The IKDC objective score was an A or B in 20 patients (83%). Arthrometer side-to-side difference averaged 3.1 ± 1.1 mm. Range of motion was normal or nearly normal in 23 patients and abnormal in 1. Of the 20 good results, 17 patients resumed sports activity at the preinjury level. Conclusion: A 2-stage revision is an accepted option in cases of excessive tunnel enlargement and bone loss, especially on the femoral side, to achieve anatomic reconstruction. Nonanatomic over-the-top ACL reconstruction and lateral extra-articular plasty technique allow one to overcome difficult anatomic situations on the femoral side, permitting a 1-step surgery. The overall results obtained in this series are comparable with those of other ACL revision series. The higher rate of mild instability observed in our series may not be attributable to the surgical technique but rather to the chronic instability suffered by these knees before last revision.

Combined Arthroscopic Treatment of Tibial Plateau and Intercondylar Eminence Avulsion Fractures

Fractures of the tibial plateau represent 1% of all fractures and 8% of fractures in the elderly population1. These fractures represent a surgical challenge because of the variety of fracture patterns and the associated soft-tissue injuries. If not adequately treated, these fractures often cause persistent knee pain, arthritis, and angular deformity. In one study, posttraumatic knee arthritis following a tibial plateau fracture was reported, after a seven-year follow-up, in 74% of patients with an associated meniscal tear and in 34% of patients with intact menisci2. Intercondylar eminence avulsion fractures are relatively uncommon. First described by Poncet in 1875, this injury usually has been considered to be the childhood equivalent of anterior cruciate ligament rupture in adults3. As an isolated injury, these fractures are most frequent in pediatric patients between the ages of eight and fourteen years4-9. These lesions also can occur in adults in association with another periarticular injury or a tibial plateau fracture3,5. In our experience, 19.4% of tibial plateau fractures have been associated with an intercondylar eminence fracture whereas 84.3% of tibial spine fractures in adults have been associated with a tibial plateau fracture (unpublished data). Associated tibial plateau and intercondylar eminence avulsion fractures are complex articular lesions that vary widely from one patient to another, and therefore treatment requires personalized solutions. When determining the best treatment, anatomic joint reconstruction with minimally invasive techniques should be considered. Arthroscopic reduction and internal fixation have demonstrated various advantages over open reduction and internal fixation in terms of surgical morbidity, time of hospital stay, recovery, and complications such as infection and loss of knee motion10-12. The high prevalence of associated intra-articular lesions justifies the use of arthroscopy to evaluate and treat all of …

Paper # 259: Augmentation Technique with Hamstring Tendons in Chronic Partial Lesions of ACL: Clinical and Arthrometric Analysis

ACL (anterior cruciate ligament) partial tears include various types of lesions, and an high rate of these lesions evolve into complete tears. Most of the techniques described in literature for the surgical treatment of chronic partial ACL tears, don9t spare the intact portion of the ligament. Aim of this study was to perform a prospective analysis of the results obtained by augmentation surgery using gracilis and semitendinosus tendons to treat partial sub-acute lesions of the ACL. This technique requires an “over the top” femoral passage, which enables salvage and strengthening of the intact bundle of ACL. The study included 97 patients treated consecutively at our Institute from 1993 to 2004 with a mean injury-surgery interval of 23 weeks (12–39). Patients were followed up by clinical and instrumental assessment criteria at 3 months, 1 year and 5 years after surgery. Clinical assessment was performed with the IKDC form. Subjective and functional parameters were assessed by the Tegner activity scale. Instrumental evaluation was done using the KT-2000 instrument: the 30 pound passive test and the manual maximum displacement test were performed. We obtained good to excellent results in 95.9% of cases. We didn9t observed recurrences in ligamentous laxity. We believe that the described technique has the advantage of being little invasive, compatible with the ACL anatomy, and enables very rapid functional recovery and return to sport.