Severe posttraumatic radiocarpal cartilage damage: first report of autologous chondrocyte implantation

Autologous chondrocyte transplantation in the treatment of thumb CMC joint osteoarthritis

Degenerative thumb carpometacarpal (CMC) joint osteoarthritis is a common disease in women starting at 40-50 years of age. Nevertheless, synovitis and initial cartilage damage start earlier, and then degenerative arthritis develops leading to joint narrowing with progressive exposure of subchondral bone, subluxation, osteophyte formation and joint deformity that can impact the surrounding joints. The aim of this study was to evaluate the outcome of patients treated with autologous chondrocyte transplantation at the thumb CMC joint at early stages. A prospective study on 10 cases of thumb CMC osteoarthritis in 8 patients was done. The thumbs were stage Eaton II (2 cases) and III (8 cases) and were treated by CMC arthroplasty with the implant of autologous chondrocytes by an open or arthroscopic technique. Two patients were treated bilaterally. Preoperatively all patients had persistent pain resistant to various kinds of nonoperative treatments for at least 1 year. Mean preoperative pinch strength was 3.7 Kg pain on VAS was 8, DASH was 55. All patients had limited abduction and flexion at the end range. Ethics committee approval was obtained for this study. Fragments of 3-4 mm of cartilage were harvested by arthroscopy or by an open technique from the wrist or elbow joint. Cartilage cells were sent to the laboratory to be grown on a collagenous biphasic matrix (MACI/Novocart®). After 3 weeks, the chondrocyte augmented scaffold was ready to be implanted in the thumb CMC joint, or frozen for a second operation later. All patients were females aged 42-67 years (mean 52 years). The dominant hand was treated in 6 cases. In 7 cases, the patients were operated with an open technique and in three cases by arthroscopy. Partial trapezium resection and dorsoradial ligament reconstruction was added to stabilize the CMC joint in most cases. Patients were seen in person at 1, 3, and 6, months, 1 year, 2 years, and 5 years after the initial surgery. Patients (nine thumbs) were then reviewed at a mean follow up 8 years (range 4.4-11 years); pain on VAS, Mayo, DASH and PRWE scores were evaluated at follow-up. One patient was lost to follow-up after 2 years. Of those nine hands, seven had an excellent result according to Mayo score, one had a good result. One thumb CMC joint was still painful and was reoperated and converted to arthroplasty after 4.4 years. All patients regained full range of motion. Mean pinch strength increased to 6.25 ± 1.3 Kg, mean DASH score was 7.3 ± 6.7; pain on VAS was 1.0 ± 1.5; these data were statistically significant compared to preoperative values (p < 0.01). Grip strength also increased in all cases, but this was not statistically significant. PRWE was 7.7 ± 6.4. No complications occurred postoperatively. The results obtained are encouraging since the implanted cartilage has lasted a mean of 8 years and up to 11 years. Biological tissue engineering techniques are being developed and could be a new solution to restore normal cartilage in young patients to postpone more aggressive surgical procedures until an older age. In cases of CMC joint instability, a ligament stabilization procedure was added to avoid subsequent damage to the implanted neocartilage. A longer follow-up and a greater number of cases are necessary to definitively establish the usefulness of this procedure, which has the advantage of being completely biological but the disadvantage of being costly.

Differences of radiocarpal cartilage alterations in arthritis and osteoarthritis using morphological and biochemical magnetic resonance imaging without gadolinium-based contrast agent administration

OBJECTIVES

To identify differences of radiocarpal cartilage alterations in osteoarthritis and arthritis using multiparametrical magnetic resonance imaging (MRI) comprising morphological and biochemical sequences without gadolinium-based contrast agent administration.

METHODS

In this prospective study, multiparametrical MRI of the radiocarpal cartilage was performed in 47 participants (mean age, 46.6 ± 17.6 years; min., 20 years; max., 79 years) on a 3 Tesla MRI. The cohort consisted of 11 patients suffering from arthritis, 10 patients with osteoarthritis, 14 patients after distal radius fracture, and 12 healthy volunteers. The radiocarpal cartilage was assessed using morphological (DESS, TrueFISP) and biochemical (T2*) MRI sequences without the application of intravenous contrast agent. The modified Outerbridge classification system for morphological and region-of-interest analyses for biochemical analysis was applied to assess the degree of cartilage damage in each patient before data were statistically tested for significant difference between the groups using a post hoc Tukey test.

RESULTS

In morphological imaging, cartilage damage was significantly more frequent in arthritis and osteoarthritis than in healthy volunteers (DESS: p = 0.01, p = 0.0004; TrueFISP: p = 0.02, p = 0.0001). In T2* imaging, patients with osteoarthritis showed higher cartilage damage compared to patients with arthritis (p = 0.01).

CONCLUSION

With multiparametrical MRI, it is possible to identify differences of radiocarpal cartilage alterations of patients with arthritis and osteoarthritis using the combination of morphological and biochemical MR imaging of the radiocarpal cartilage without the application of contrast agent. Multiparametrical MRI without the usage of contrast agent may be a potential tool helping to distinguish both entities.

KEY POINTS

• Multiparametrical MRI with morphological and biochemical sequences allows the differentiation of patients with arthritis and osteoarthritis. • High-resolution MRI of radiocarpal cartilage is possible without administration of contrast agent.

Hydrogels for Cartilage Regeneration, from Polysaccharides to Hybrids

The aims of this paper are: (1) to review the current state of the art in the field of cartilage substitution and regeneration; (2) to examine the patented biomaterials being used in preclinical and clinical stages; (3) to explore the potential of polymeric hydrogels for these applications and the reasons that hinder their clinical success. The studies about hydrogels used as potential biomaterials selected for this review are divided into the two major trends in tissue engineering: (1) the use of cell-free biomaterials; and (2) the use of cell seeded biomaterials. Preparation techniques and resulting hydrogel properties are also reviewed. More recent proposals, based on the combination of different polymers and the hybridization process to improve the properties of these materials, are also reviewed. The combination of elements such as scaffolds (cellular solids), matrices (hydrogel-based), growth factors and mechanical stimuli is needed to optimize properties of the required materials in order to facilitate tissue formation, cartilage regeneration and final clinical application. Polymer combinations and hybrids are the most promising materials for this application. Hybrid scaffolds may maximize cell growth and local tissue integration by forming cartilage-like tissue with biomimetic features.

Characterization of primary chondrocytes harvested from hips with femoroacetabular impingement

OBJECTIVE

Acetabular chondral lesions are common in patients with femoroacetabular impingement (FAI) syndrome. The aim of this study was (1) to evaluate the proliferation potential of primary human chondrocytes (hC) derived from both acetabular and femoral site and (2) to validate cellular differentiation during three-dimensional (3D) cultivation as a prerequisite for autologous matrix-assisted cartilage regeneration of the hip joint.

METHODS

hC were isolated from cartilage samples obtained from N = 6 patients during offset reconstruction. Proteoglycan content was assessed by Safranin-O staining. Proliferation and cell viability were quantified by microscopic cell counting and Trypan Blue exclusion. Messenger ribonucleic acid (mRNA) expression levels of collagen type 1 and 2, aggrecan (ACAN), and interleukin-1β (IL-1β) genes were assessed upon monolayer cultivation, after 48 h/4-10°C - transport simulation and after 14 days of 3D hydrogel cultivation.

RESULTS

Primary hC from acetabular and femoral damaged sites were viable. No significant intergroup differences were observed concerning cell viability (>95%) after monolayer cultivation and transport simulation. Harvest yields from acetabular and femoral cartilage samples were comparable to that known from knee joints (mean ± standard deviation (SD), 13.4 × 10(6) ± 5 × 10(6) cells per culture vs 20 × 10(6) cells). Redifferentiation was induced during 3D hydrogel cultivation as observed by increased levels of collagen II (1000-fold) and ACAN (10-fold) gene vs monolayer cultivation (P < 0.001).

CONCLUSION

hC derived from damaged acetabular and femoral site are qualified for autologous matrix-assisted cartilage transplantation paving the way for cell-based cartilage regeneration in FAI patients.

Collagen Type II enhances chondrogenic differentiation in agarose-based modular microtissues

BACKGROUND AIMS

Cell-based therapies have made an impact on the treatment of osteoarthritis; however, the repair and regeneration of thick cartilage defects is an important and growing clinical problem. Next-generation therapies that combine cells with biomaterials may provide improved outcomes. We have developed modular microenvironments that mimic the composition of articular cartilage as a delivery system for consistently differentiated cells.

METHODS

Human bone marrow-derived mesenchymal stem cells (MSC) were embedded in modular microbeads consisting of agarose (AG) supplemented with 0%, 10% and 20% collagen Type II (COL-II) using a water-in-oil emulsion technique. AG and AG/COL-II microbeads were characterized in terms of their structural integrity, size distribution and protein content. The viability of embedded MSC and their ability to differentiate into osteogenic, adipogenic and chondrogenic lineages over 3 weeks in culture were also assessed.

RESULTS

Microbeads made with <20% COL-II were robust, generally spheroidal in shape and 80 ± 10 µm in diameter. MSC viability in microbeads was consistently high over a week in culture, whereas viability in corresponding bulk hydrogels decreased with increasing COL-II content. Osteogenic differentiation of MSC was modestly supported in both AG and AG/COL-II microbeads, whereas adipogenic differentiation was strongly inhibited in COL-II containing microbeads. Chondrogenic differentiation of MSC was clearly promoted in microbeads containing COL-II, compared with pure AG matrices.

CONCLUSIONS

Inclusion of collagen Type II in agarose matrices in microbead format can potentiate chondrogenic differentiation of human MSC. Such compositionally tailored microtissues may find utility for cell delivery in next-generation cartilage repair therapies.