High-dose antibiotic-loaded acrylic cement (ALAC) is used for managing peri-prosthetic joint infections (PJIs). The marked increase in resistant high-virulence bacteria is drawing the attention of physicians toward alternative antimicrobial formulations loaded into acrylic bone cement. The aim of this in vitro study was to determine the elution kinetics of 14 different high-dose ALACs. All ALAC samples showed a burst release of antibiotics in the first hour, progressively decreasing over time, and elution curves strictly adhered to a nonlinear regression analysis formula. Among aminoglycosides, commonly seen as the most appropriate antibiotics to be loaded into the bone cement, the highest elution rate was that of tobramycin. Among the glycopeptides, a class of antibiotics that should be considered to treat PJIs because of the prevalence of aminoglycoside resistance, vancomycin showed better elution than teicoplanin. Clindamycin, which can be associated with aminoglycosides to prepare ALACs and represents a useful option against the most common pathogens responsible for PJIs, showed the highest absolute and relative elutions among all the tested formulations. A noticeable elution was also detected for colistin, an antibiotic of last resort for treating multidrug-resistant bacteria. The current study demonstrates theoretical advantages in the preparation of ALAC for some antibiotics not routinely used in the clinical setting for PJIs. The use of these antibiotics based on the infecting bacteria sensitivity may represent a useful option for physicians to eradicate PJIs. In vivo testing should be considered in the future to confirm the results of this study.
The use of modular endoprostheses is a viable option to manage both tumor resection and severe bone loss due to nonneoplastic conditions such as fracture sequelae, failed osteoarticular grafts, arthroplasty revisions, and periprosthetic fractures. We sought to investigate both midterm complications and failures occurred in 87 patients who underwent a megaprosthetic reconstruction in a nonneoplastic setting. After a mean follow-up of 58 (1–167) months, overall failure-free survival was 91.5% at 1 year, 80% at 2 years, 71.6% at 5 years, and 69.1% at 5 and 10 years. There was no significant difference in the survival rate according to the diagnosis at the index procedure (), nor to the reconstruction site (). The use of megaprostheses in a postneoplastic setting did not affect survival rate in comparison with endoprosthetic reconstruction of pure nonneoplastic conditions (). Perimegaprosthetic infection was the leading complication, occurring in 10 (11.5%) patients and implying a megaprosthetic revision in all but one case. Physicians should consider these results when discussing with patients desired outcomes of endoprosthetic reconstructions of a nonneoplastic disease.
Introduction: Insulin-like growth factor I (IGF-I) regulates articular cartilage homeostasis. During osteoarthritis (OA), the anabolic responses of chondrocytes to IGF-I are likely to be prevented by the enhanced production of IGF-binding proteins (IGFBPs), especially IGFBP-3. The aim of this study is to evaluate whether the architectural transcription factor high mobility group A1 (HMGA1) influences IGFBP-3 overexpression in vitro, in cultured chondrocytic cell lines, and ex vivo, in human osteoarthritic cartilage compared to healthy human cartilage controls. Methods: Quantitative real-time reverse transcription-PCR (qRT-PCR) was performed to assess the relative transcript levels of HMGA1 and IGFBP-3 in vitro, in the human chondrocytic cell lines T/C-28a4 and C-28/I2. An electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP) and transient transfection assays were performed to investigate the HMGA1-IGFBP-3 gene interaction. Samples of articular cartilage were harvested from osteoarthritic patients and controls and analyzed by qRT-PCR for HMGA1 and IGFBP-3 mRNA levels. Results: A parallelism between HMGA1 protein levels and IGFBP-3 gene expression has been observed in T/C-28a4 and C-28/I2 cells. The interaction of HMGA1 with the IGFBP-3 gene promoter has been demonstrated by EMSA and ChIP. In transient transfections, IGFBP-3 promoter activity increased in cells overexpressing HMGA1 and decreased in cells pretreated with siRNA detected against HMGA1. IGFBP-3 mRNA expression was higher in cartilage from patients with OA, where the increased expression of IGFBP-3 closely paralleled the increased expression of HMGA1 mRNA. Conclusions: Our observations indicate that increased HMGA1 expression in human chondrocytes is associated with increased expression of IGFBP-3. It is tempting to speculate that, through the regulation of IGFBP3 expression, HMGA1 may act as a pathogenetic factor for OA.
4 January 2019 in Acta Orthopaedica et Traumatologica Turcica
Malignant glomus tumors (MGTs) are exceptional but pose diagnostic and therapeutic challenges. Wide resection is the recommended treatment method, however, no data are available concerning adjuvant therapies. We present an exceptional case of extradigital deep-seated MGT of the forearm, with an exceptional bone infiltration. Despite being treated with wide resection, the patient had an optimal functional outcome, no functional loss, no motor or sensitive deficits and has returned to his full daily activity. ER -
26 July 2023 in Journal of Shoulder and Elbow Surgery
Literature describing outcomes and integrity after isolated subscapularis (SSC) tendon repair is emerging but remains limited to a few small case series with short-term follow-up. The aim of this study was to evaluate the long-term clinical outcomes and repair integrity in patients who underwent arthroscopic repair of isolated SSC tears. A retrospective study was conducted with the following inclusion criteria: (1) primary and elective shoulder arthroscopy for isolated SSC repair, (2) type III (a full-thickness tear in the upper two-thirds of the tendon) or IV (a complete tear without tendon retraction) SSC tear according to the Lafosse classification, and (3) a minimum 24-month follow-up. Preoperatively, the range of motion (ROM) and the Constant-Murley score (CMS) and at follow-up, the ROM, the University of California-Los Angeles (UCLA) Shoulder Rating Scale, the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and the CMS were evaluated; an ultrasonographic assessment of tendon healing was performed according to the Sugaya classification. The final sample consisted of 45 patients with an average age of 55 ± 9 years. After a mean follow-up time of 107 ± 54 months, the mean UCLA and DASH scores were 8.7 ± 1.3 and 42.2 ± 6.4, respectively. ROM and CMS showed statistically significant improvements (all P < .001). Before surgery, the mean CMS was 49% that of sex- and age-matched healthy individuals, and all patients showed a CMS lower than the normative data. At the final follow-up visit, the mean CMS was 94.2% that of sex- and age-matched healthy individuals, and no patients showed CMS of 30 or less. The mean increase in the CMS was 41.4 ± 9.8 points (range, 23-60 points). The ultrasonographic assessment showed SSC tendon healing in 39 (86.7%) cases; tendon retear was recorded in 5 (13.3%) cases. All scores directly correlated with the healing of the tendon. A higher postoperative DASH score was associated with male sex (P = .039, β = 5.538) and a longer follow-up period (P = .044, β = 0.001). The postoperative CMS (P < .001) and UCLA scores (P = .001) were significantly higher in patients younger than 60 years of age at surgery than in older individuals. Arthroscopic repair of isolated SSC tears achieves excellent clinical and functional results at a mean of 9 years postoperatively, with a satisfactory healing rate. Better functional outcomes correlate with SSC tendon integrity and were observed in male patients and in those younger than 60 years at surgery.