Targeting Bone Alleviates Osteoarthritis in Osteopenic Mice and Modulates Cartilage Catabolism

Subchondral bone modifications occur early in the development of osteoarthritis (OA). The level of bone resorption might impact cartilage remodeling. We therefore assessed the in vivo and in vitro effects of targeting bone resorption in OA and cartilage metabolism.OA was induced by meniscectomy (MNX) in ovariectomized osteopenic mice (OP) treated with estradiol (E2), pamidronate (PAM), or phosphate buffered saline (PBS) for 6 weeks. We assessed the subchondral bone and cartilage structure and the expression of cartilage matrix proteases. To assess the involvement of bone soluble factors in cartilage metabolism, supernatant of human bone explants pre-treated with E2 or PAM were transferred to cartilage explants to assess proteoglycan release and aggrecan cleavage. OPG/RANKL mRNA expression was assessed in bone explants by real-time quantitative PCR. The role of osteoprotegerin (OPG) in the bone-cartilage crosstalk was tested using an OPG neutralizing antibody.Bone mineral density of OP mice and osteoclast number were restored by E2 and PAM (p<0.05). In OP mice, E2 and PAM decreased ADAMTS-4 and -5 expression, while only PAM markedly reduced OA compared to PBS (2.0±0.63 vs 5.2±0.95; p<0.05). OPG/RANKL mRNA was increased in human bone explants treated with both drugs (2.2-3.7-fold). Moreover, supernatants from bone explants cultured with E2 or PAM reduced aggrecan cleavage and cartilage proteoglycan release (73±8.0% and 80±22% of control, respectively, p<0.05). This effect was reversed with osteoprotegerin blockade.The inhibition of bone resorption by pamidronate in osteopenic mice alleviates the histological OA score with a reduction in the expression of aggrecanases. Bone soluble factors, such as osteoprotegerin, impact the cartilage response to catabolic factors. This study further highlights the importance of subchondral bone in the regulation of joint cartilage damage in OA

Medium to long-term results of a recessed glenoid for glenoid resurfacing in total shoulder arthroplasty

Background: Recessed mini-glenoid components provide an alternative to total shoulder replacement that may avoid some of the known shortcomings and complications associated with shoulder hemiarthroplasty or standard glenoid components in difficult cases. This study reports survivorship, radiological and clinical outcomes of a recessed mini-glenoid implant in a consecutive cohort. Methods: Retrospective cohort study reporting outcomes of 28 consecutive shoulders (27 patients) following total shoulder replacement using a recessed, cemented mini-glenoid implant at two sites. Results: The most frequent diagnosis was primary osteoarthritis (79%); glenoid morphology was Walch Type A (67%), B1 15%, B2 10% and C 10%. At final follow-up, pain was 16.3 (SD = 23.1), American Shoulder and Elbow Score was 64.5 (SD = 31.9) and (normalized) Constant score was 83.0 (SD = 20.7). Implant survivorship at average final follow-up of seven years (3–13) was 96.4%. Seven mini-glenoids showed small peripheral radiolucent lines at one-year X-ray follow-up but were non-progressive on subsequent imaging. Discussion: Recessed polyethylene mini-glenoid is an attractive alternative for shoulder arthroplasty and provides an intermediate solution between standard glenoid components and hemiarthroplasty. Our medium to long-term results demonstrate reliable clinical outcomes, absence of glenoid erosion, low complication rate and satisfactory implant survivorship

High degree of consensus achieved regarding diagnosis and treatment of acromioclavicular joint instability among ESA-ESSKA members

Purpose To develop a consensus on diagnosis and treatment of acromioclavicular joint instability. Methods A consensus process following the modified Delphi technique was conducted. Panel members were selected among the European Shoulder Associates of ESSKA. Five rounds were performed between October 2018 and November 2019. The first round consisted of gathering questions which were then divided into blocks referring to imaging, classifications, surgical approach for acute and chronic cases, conservative treatment. Subsequent rounds consisted of condensation by means of an online questionnaire. Consensus was achieved when >= 66.7% of the participants agreed on one answer. Descriptive statistic was used to summarize the data. Results A consensus was reached on the following topics. Imaging: a true anteroposterior or a bilateral Zanca view are sufficient for diagnosis. 93% of the panel agreed on clinical override testing during body cross test to identify horizontal instability. The Rockwood classification, as modified by the ISAKOS statement, was deemed valid. The separation line between acute and chronic cases was set at 3 weeks. The panel agreed on arthroscopically assisted anatomic reconstruction using a suspensory device (86.2%), with no need of a biological augmentation (82.8%) in acute injuries, whereas biological reconstruction of coracoclavicular and acromioclavicular ligaments with tendon graft was suggested in chronic cases. Conservative approach and postoperative care were found similar Conclusion A consensus was found on the main topics of controversy in the management of acromioclavicular joint dislocation. Each step of the diagnostic treatment algorithm was fully investigated and clarified