Marco De Gori

Recent Findings on the Role of Gelatinases (Matrix Metalloproteinase-2 and -9) in Osteoarthritis

Several studies dealing with the pathomechanisms of OA refer to MMP-1, -3, -7, -8, and -13 whereas a smaller number of investigations have pointed out the pathogenic role of gelatinases in OA. These gelatinases are best known for their involvement in pulmonary, myocardial, and neoplastic disease but they are emerging as important proteases implicated in the OA progression. This paper highlights the role of the gelatinases as emerging factors in OA pathogenesis through the regulation of subchondral bone resorption and microvascular invasion. The most significant new findings over the last year that add to our knowledge of the activity of these proteins in OA have been reported.

Midterm Results and Complications After Minimally Invasive Distal Metatarsal Osteotomy for Treatment of Hallux Valgus

Background: Minimally invasive distal metatarsal osteotomy (MIDMO) is a common technique used to correct the hallux valgus deformity, but controversy remains regarding the expected outcomes of this surgery. Methods: Seventy-two patients (85 feet) suffering from hallux valgus underwent MIDMO with a modified Bösch technique. Patients were prospectively evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) hallux score, and the AOFAS recovery rate was calculated. Before surgery and at follow-up, the hallux valgus (HVA), intermetatarsal (IMA), and distal metatarsal articular (DMAA) angles were measured, and the severity of disease was categorized according to the preoperative HVA. The tibial sesamoid position and articular congruence were evaluated. Postoperative complications were noted. Results: After an average follow-up of 73.3 ± 38.1 months, the total AOFAS score improved from 47.6 ± 13.3 to 87.3 ± 11.5 (P < .001). The HVA decreased from 34.7 ± 8.2 to 14.8 ± 7.8 degrees, the IMA from 14.7 ± 4 to 6.6 ± 3.6 degrees, and the DMAA from 20.9 ± 9.8 to 9 ± 6.6 degrees (P < .001 for all). Postoperative improvement in AOFAS was inversely related to the preoperative severity of disease (P < .001, β = –.378). Sixteen (18.8%) deformity recurrences were noted, 9 of which were observed in patients with preoperative HVA more than 40 degrees. Worse preoperative congruence of the metatarsophalangeal joint and tibial sesamoid position correlated with a higher rate of recurrence of the disease after surgery (P = .001, β = –.353 and P < .001, β = .427, respectively). Conclusions: Satisfactory clinical and radiological results can be expected after MIDMO, but caution should be exercised when using this technique because of the likelihood of possible complications (29.4% overall complication rate). Predictors of surgical outcomes can be used to select the best candidates for this surgery. Level of Evidence: Level IV, case series.

Drug elution from high-dose antibiotic-loaded acrylic cement: a comparative, in vitro study.

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.

Functional relationship between high mobility group A1 (HMGA1) protein and insulin-like growth factor-binding protein 3 (IGFBP-3) in human chondrocytes

IntroductionInsulin-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.MethodsQuantitative 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.ResultsA 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.ConclusionsOur 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.

Radial artery achieves better flowmetric results than saphenous vein in the elderly

Due to the limited life expectancy and the supposed higher morbidity with complete arterial grafting, extensive arterial graft in the elderly is still questioned. It was the aim of this study to evaluate transit time flow and clinical, biochemical and echocardiographic results of elderly patients undergoing coronary artery bypass grafting (CABG) with either saphenous vein (SV) or radial artery (RA) employed as the second conduit of choice. The present study evaluates clinical and flowmetric results of a prospective series of elderly patients (≥70 years old) undergoing RA CABG (75 patients, Group A) or SV CABG (163 patients, Group B) during isolated myocardial revascularization, performed either off-pump (OPCABG) and onpump during the last 5 years at a single academic institution (between January 2003 and December 2007). Transit time flowmetric (TTF) maximum and mean flow, pulsatility index (P.I.), and graft flow reserve (GFR) were compared. Hospital outcome was analyzed. Clinical data were compared between the two groups and one-year follow-up was completed. The two groups showed comparable preoperative and intraoperative variables. When TTF analysis was considered, patients undergoing RA grafting demonstrated a significantly higher maximum (systolic) and mean flow compared to SV grafting, either in circumflex, diagonal, and right coronary territory. Pulsatility index was significantly lower in the RA group in circumflex, diagonal, and right coronary grafts. Furthermore, when GFR was calculated significantly higher values were found in RA conduits in the circumflex, diagonal, and right coronary grafts. Comparable troponin I leakage was detected between the two groups. Postoperative variables addressing hospital outcome were similar in the two groups. When echocardiographic data were analyzed, no differences were recorded in postoperative recovery of left ventricular ejection fraction and wall motion score index. One-year follow-up showed better freedom from acute cardiovascular events in the RA group (P = 0.04). Our data show that despite comparable clinical, biochemical, and echocardiographic results in elderly patients undergoing RA or SV grafting, better flowmetric results — in terms of GFR, mean flow, and Pulsatility index — can be detected in arterial conduits.

Modular Endoprostheses for Nonneoplastic Conditions: Midterm Complications and Survival

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 (p = 0.921), nor to the reconstruction site (p = 0.402). The use of megaprostheses in a postneoplastic setting did not affect survival rate in comparison with endoprosthetic reconstruction of pure nonneoplastic conditions (p = 0.851). 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.

Synovial hemangioma and osteoarthritis of the knee: a case report

This report presents an adult patient suffering from knee osteoarthritis and gross hypertrophy of the synovium, preoperatively interpreted as a nonspecific synovial reaction. The patient underwent a total knee replacement and a complete synovectomy was performed. Histological examination disclosed a synovial hemangioma, which is a rare intra-articular, benign tumor of youth.

Risk Factors for Perimegaprosthetic Infections After Tumor Resection

Periprosthetic joint infection remains one of the most challenging and pervasive complications following megaprosthetic replacement after tumor resection. The authors conducted a systematic review of the literature for clinical studies that reported a risk factor analysis for perimegaprosthetic joint infections. The search included English-language studies published up to July 2015. Eight studies fulfilled the inclusion criteria. Identified factors mostly related to both surgical procedure and hospitalization. Physicians should consider these results when discussing the outcomes of limb salvage surgery with patients and trying to reduce the overall burden of perimegaprosthetic joint infections. [Orthopedics. 2017; 40(1):e11-e16.].

Hydatid cyst in the vastus lateralis muscle: a case report

Hydatidosis is a zoonotic disease; human infection occurs through the consumption of food and water contaminated with the eggs of parasites of the Echinococcus type. While the liver is the most common site of infection, involvement of the musculoskeletal system is extremely rare. In the context of musculoskeletal involvement, the spine is the most commonly infected site, while the muscles are rarely infected and account for approximately <1% of cases. It has been suggested that muscles provide an unsuitable environment for the parasite, because of the presence of lactic acid. The cysts appear as slow-growing masses of soft tissue, and signs of inflammation and fistulization often coexist. We report a rare case of an hydatid cyst located in the vastus lateralis muscle of a 41-year-old man. Muscular echinococcosis is an extremely rare disease. A MRI evaluation should be taken into account as gold standard in the diagnosis. Surgical cystectomy is often indicated, and an excision with wide margins is mandatory to avoid the rupture of the cyst and anaphylaxis. Adjuvant pharmacological therapy is recommended to minimize the risk of recurrence.

Giant schwannoma of the foot: a case report and literature review

A schwannoma is a rare, benign tumor originating from Schwann cells of peripheral nerve sheath. It commonly occurs in subjects between 20 and 50 years of age, and its malignant transformation is exceptional. While schwannomas usually affect the head and neck region, localization in the lower extremity is exceptionally rare, and even fewer cases have described schwannomas occurring in the foot. We report a case of a giant schwannoma of the foot diagnosed in a 65-year-old woman. A giant schwannoma of the foot is an extremely rare soft tissue tumor. MRI may allow an earlier diagnosis and provide valuable information about the size and possible bone invasion. This case report noted that a complete excision of the schwannoma may prevent the risk of local recurrence, regardless of its size.