Federico Alberto Grassi

Autologous chondrocyte implantation using a bilayer collagen membrane: A preliminary report

Purpose. To present preliminary clinical experience with Matrix-induced autologous chondrocyte implantation, a new tissue-engineering technique for treatment of deep cartilage defects, in which autologous chondrocytes are seeded on a tridimensional scaffold provided by a bilayer type I–III collagen membrane. Methods. From December 1999 to January 2001, 13 patients underwent implantation procedure for deep cartilage defects. Age of patients ranged from 18 to 49 years (mean age, 35 years). The mean defect size was 3.5 cm2 (range, 2.0–4.5 cm2). Clinical and functional evaluation were performed using various score systems for the ankle and the knee, and magnetic resonance imaging was performed at 6 and 12 months postoperatively. Membrane structure and cellular population were investigated by light microscopy, scanning electron microscopy, and electrophoresis before implantation. Results. The mean follow-up was 6.5 months (range, 2–15 months). No complications were observed in the postoperative period. The 6 patients with a minimum follow-up of 6 months showed an improvement in clinical and functional status after surgery. Magnetic resonance images showed the presence of hyaline-like cartilage at the site of implantation; there was evidence of chondroblasts and type II collagen inside the seeded membrane. Conclusion. Matrix-induced autologous chondrocyte implantation offers several advantages with respect to the traditional cultured cell procedure. These include technical simplicity, short operating time, minimal invasiveness, and easier access to difficult sites. It appears to be a reliable method for the repair of deep cartilage defects.

Six-year experience with the Delta III reverse shoulder prosthesis

Purpose. To report the clinical and radiographic results and complications of the Delta III reverse prosthesis. Methods. 24 women and 2 men aged 62 to 84 (mean, 75) years underwent total shoulder replacement using the Delta III reverse prosthesis. Patient diagnoses were massive rotator cuff tear (n=20), disabling sequelae of proximal humeral fractures (n=3), and failure of an unconstrained arthroplasty (n=3). Clinical and functional results were assessed using the Constant scale. Active range of motion (ROM) was measured. Scapular notching and radiolucent lines around the humeral component were evaluated using radiographs. Patient satisfaction of the treatment was evaluated by a direct interview. Results. 23 patients were followed up for 26 to 84 (mean, 42) months. Two patients had loosening of the glenoid component (at 6 months and 5 years) and underwent revision surgery. There were no instances of infection, instability, or acromial fracture. Only active elevation improved significantly after surgery, as did both the absolute and adjusted Constant scores. 12 patients were completely pain-free, 9 complained of slight pain, and one of moderate pain. The severity of scapular notching progressed with time. 15 patients were satisfied with the treatment, 6 were partially satisfied, and 2 were not satisfied. Conclusion. The Delta III prosthesis restores shoulder function but has biomechanical limits. Its use should be limited to elderly patients with severe impairment of the glenohumeral joint. Scapular notching is a main concern for the long-term survival of the implant.

Short-term evaluation of collagen meniscus implants by MRI and morphological analysis

Abstract Meniscectomy can lead to degenerative joint changes in the knee. Collagen meniscus implantation is a tissue engineering technique designed to stimulate regeneration of meniscal tissue in case of irreparable tears or previous meniscectomy. The implant is composed of type I collagen derived from bovine Achilles tendon and enriched with glycosaminoglycans. Previous clinical trials demonstrated satisfactory medium-term results in patients who received a collagen meniscus implant (CMI). In this study, CMI structure was analysed by light microscopy and scanning electronic microscopy (SEM). The same morphological studies were performed on two implant biopsies, obtained from two patients who underwent a second arthroscopic look six months after implantation. The evolution of the implant was also investigated by magnetic resonance imaging, 6 and 12 months postoperatively. CMI presented a multilamellar structure, with inner lacunae allowing tissue ingrowth. The lamellae were made of collagen fibrils, randomly oriented and preserving the typical 64-nm period. At second arthroscopic look, the implant appeared in continuity to the native residual meniscus and parameniscus, and showed good consistency and stability at probing. The biopsy specimens demonstrated invasion of the scaffold by connective tissue and blood vessels. The newly synthesised collagen fibrils were clearly distinguishable from the scaffold ones. No phagocytomacrophagic cells nor inflammatory reactions were observed inside the implant. MRI findings confirmed CMI biocompatibility and highlighted the evolution of the integration process with time. The data achieved in this study support the hypothesis that CMI stimulates regeneration of meniscal-like tissue, which could prevent the development of degenerative changes after meniscectomy.

Long-term outcome of Rockwood capsular shift for recurrent shoulder dislocation

Purpose To review the long-term outcome of Rockwood capsular shift for recurrent shoulder dislocation secondary to trauma. Methods Records of 30 males and 4 females who underwent Rockwood capsular shift for recurrent (≥2 episodes) anterior shoulder dislocation were reviewed. An additional Bankart repair with different techniques was performed in 24 of the patients by 2 different surgeons. The outcome was assessed using the Western Ontario Shoulder Instability Index (WOSI) and the Western Ontario Osteoarthritis of the Shoulder (WOOS) index questionnaires, the modified Rowe score, and the Constant-Murley score. Shoulder range of motion (ROM) was measured. Degenerative joint changes were evaluated on radiographs. Results During a mean follow-up of 13 (range, 10–16) years, 6 (18%) patients had a mean of 1.2 recurrent dislocations. Four of the patients reported a traumatic event during recurrent dislocation. Of the 6 patients, 3 had undergone a Bankart lesion repair. Better Rowe and adjusted Constant scores were associated with lower age at first dislocation, at the index surgical procedure, and at follow-up. Four patients developed glenohumeral osteoarthritis: 2 were mild or moderate and 2 were severe and symptomatic. Glenohumeral osteoarthritis was associated with follow-up duration (p=0.03) and poorer Rowe score (p=0.012), adjusted Constant score (p=0.001), and WOOS score (p=0.006). Conclusion Rockwood capsular shift can preserve shoulder ROM, with rates of recurrent dislocation and degenerative joint changes comparable with other techniques.