Jeffrey S. Kneisl

Calcium deposition in osteoarthritic meniscus and meniscal cell culture

IntroductionCalcium crystals exist in the knee joint fluid of up to 65% of osteoarthritis (OA) patients and the presence of these calcium crystals correlates with the radiographic evidence of hyaline cartilaginous degeneration. This study sought to examine calcium deposition in OA meniscus and to investigate OA meniscal cell-mediated calcium deposition. The hypothesis was that OA meniscal cells may play a role in pathological meniscal calcification.MethodsStudies were approved by our human subjects Institutional Review Board. Menisci were collected during joint replacement surgeries for OA patients and during limb amputation surgeries for osteosarcoma patients. Calcium deposits in menisci were examined by alizarin red staining. Expression of genes involved in biomineralization in OA meniscal cells was examined by microarray and real-time RT-PCR. Cell-mediated calcium deposition in monolayer culture of meniscal cells was examined using an ATP-induced 45calcium deposition assay.ResultsCalcium depositions were detected in OA menisci but not in normal menisci. The expression of several genes involved in biomineralization including ENPP1 and ANKH was upregulated in OA meniscal cells. Consistently, ATP-induced calcium deposition in the monolayer culture of OA meniscal cells was much higher than that in the monolayer culture of control meniscal cells.ConclusionsCalcium deposition is common in OA menisci. OA meniscal cells calcify more readily than normal meniscal cells. Pathological meniscal calcification, which may alter the biomechanical properties of the knee meniscus, is potentially an important contributory factor to OA.

Is PET useful in detecting occult nonpulmonary metastases in pediatric bone sarcomas

Orthopaedic oncologists are increasingly utilizing positron emission tomography (PET) technology in the initial workup and staging of sarcomas and for monitoring treatment response. We evaluated the use of PET with fluorine-18-fluoro- 2-deoxy D-glucose (FDG) to detect occult nonpulmonary metastases in patients < age 30 newly diagnosed with either Ewings or osteosarcoma, and the impact of this information upon therapeutic decision making. We retrospectively reviewed prospectively collected data (1994-2004) on 55 patients age < 30 years old over a 10 year span. PET detected metastases in 12/55 (22%) of these patients, eight of whom (67%) harbored disease outside the lung; however, only 4/55 (7%) were upstaged to Stage IV specifically due to findings determined by PET alone. Three of 17 (18%) Ewings sarcoma patients, but only one of 38 (3%) osteosarcoma patients, were upstaged by PET alone. The most important alteration in treatment decisions was the substitution of irradiation in lieu of surgery for local control in Ewings sarcoma patients.Level of Evidence: Diagnostic study, level II. See Guidelines for Authors for a complete description of levels of evidence.

Analysis of meniscal degeneration and meniscal gene expression

BackgroundMenisci play a vital role in load transmission, shock absorption and joint stability. There is increasing evidence suggesting that OA menisci may not merely be bystanders in the disease process of OA. This study sought: 1) to determine the prevalence of meniscal degeneration in OA patients, and 2) to examine gene expression in OA meniscal cells compared to normal meniscal cells.MethodsStudies were approved by our human subjects Institutional Review Board. Menisci and articular cartilage were collected during joint replacement surgery for OA patients and lower limb amputation surgery for osteosarcoma patients (normal control specimens), and graded. Meniscal cells were prepared from these meniscal tissues and expanded in monolayer culture. Differential gene expression in OA meniscal cells and normal meniscal cells was examined using Affymetrix microarray and real time RT-PCR.ResultsThe grades of meniscal degeneration correlated with the grades of articular cartilage degeneration (r = 0.672; P < 0.0001). Many of the genes classified in the biological processes of immune response, inflammatory response, biomineral formation and cell proliferation, including major histocompatibility complex, class II, DP alpha 1 (HLA-DPA1), integrin, beta 2 (ITGB2), ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), ankylosis, progressive homolog (ANKH) and fibroblast growth factor 7 (FGF7), were expressed at significantly higher levels in OA meniscal cells compared to normal meniscal cells. Importantly, many of the genes that have been shown to be differentially expressed in other OA cell types/tissues, including ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5) and prostaglandin E synthase (PTGES), were found to be expressed at significantly higher levels in OA meniscal cells. This consistency suggests that many of the genes detected in our study are disease-specific.ConclusionOur findings suggest that OA is a whole joint disease. Meniscal cells may play an active role in the development of OA. Investigation of the gene expression profiles of OA meniscal cells may reveal new therapeutic targets for OA therapy and also may uncover novel disease markers for early diagnosis of OA.

Histological Examination of Collagen and Proteoglycan Changes in Osteoarthritic Menisci

This study sought to examine collagen and proteoglycan changes in the menisci of patients with osteoarthritis (OA). Collagens were examined using picrosirius red, and hematoxylin and eosin. Proteoglycans were examined using safranin-O and alcian blue. Types I and II collagens and aggrecan were examined using immunochemistry. Severe loss of collagens was observed to occur in OA menisci, particularly in the middle and deep zones and collagen networks were less organized than those of normal menisci. In contrast, proteoglycan staining in the middle and deep zones of OA meniscus increased compared to normal control menisci. Immunohistochemistry indicated that types I and II collagens were co-localized and the loss of types I collagen in OA menisci appeared more severe in the middle and deep zones than that in the surface zones. The loss of type II collagen however was severe across all three zones. Immunohistochemistry also indicated elevated aggrecan staining in OA menisci. These findings together indicate that severe loss of collagens and intrameniscal degeneration are hallmarks of OA menisci and that extracellular matrix degeneration occurred in OA menisci follows a pathway different from that occurred in OA articular cartilage. These findings are not only important for a better understanding of the disease process but also important for the development of novel structure-modifying drugs for OA therapy.

Protocol for the Examination of Specimens From Patients With Tumors of Bone

The College of American Pathologists offers these protocols to assist pathologists in providing clinically useful and relevant information when reporting results of surgical specimen examinations of surgical specimens. The College regards the reporting elements in the ‘‘Surgical Pathology Cancer Case Summary (Checklist)’’ portion of the protocols as essential elements of the pathology report. However, the manner in which these elements are reported is at the discretion of each specific pathologist, taking into account clinician preferences, institutional policies, and individual practice. The College developed these protocols as an educational tool to assist pathologists in the useful reporting of relevant information. It did not issue the protocols for use in litigation, reimbursement, or other contexts. Nevertheless, the College recognizes that the protocols might be used by hospitals, attorneys, payers, and others. Indeed, effective January 1, 2004, the Commission on Cancer of the American College of Surgeons mandated the use of the checklist elements of the protocols as part of its Cancer Program Standards for Approved Cancer Programs. Therefore, it becomes even more important for pathologists to familiarize themselves with these documents. At the same time, the College cautions that use of the protocols other than for their intended educational purpose may involve additional considerations that are beyond the scope of these documents. PROTOCOL FOR THE EXAMINATION OF SPECIMENS FROM PATIENTS WITH TUMORS OF BONE

Acrometastasis to the Foot: Three Case Reports With Primary Colon Cancer

Acrometastasis (metastasis to the hand or foot) is a rare occurrence; however, bone is a common site of metastatic disease, which occurs in up to 30% of patients with malignancy. Although acrometastasis is rare, a high clinical suspicion must exist, especially in evaluating a patient with a known history of cancer. The diagnosis may be difficult and prolonged, which may ultimately affect the patients outcome. Misdiagnosis of acrometastasis seems to be a common problem. Early diagnosis and treatment is important for improving quality of life in these patients. The authors report 3 cases of acrometastasis from a rare source, the colon.

Predictors of Functional Recovery Following Periprosthetic Distal Femur Fractures

BACKGROUND Treatment options for periprosthetic distal femur fractures include open reduction internal fixation (ORIF) and distal femoral replacement (DFR). The purpose of this study was to evaluate the complications, and functional recovery (ambulatory status, living situation, mortality) in patients undergoing operative treatment (DFR and ORIF) of periprosthetic distal femur fractures. METHODS A retrospective review of 58 patients with distal femoral periprosthetic fractures treated with either ORIF or DFR was conducted. Surgical complications, discharge disposition, ambulatory status, living situation at 1 year, and mortality at 1 year were compared between patients treated with ORIF and DFR. Outcomes at 1 year were also compared between patients older and younger than 85 years of age. RESULTS Fifty-eight patients with a mean age of 80 years (range, 61-95 years) met inclusion criteria. The mean follow-up was 29.5 months (range, 5-81 months). Patients undergoing DFR were significantly older than those who underwent ORIF (83 vs 78, P < .01). The 1-year mortality rate was 20.6%. There was no difference between groups with respect to mortality, complications, discharge disposition, or ambulatory status and living situation at 1 year. Patients who lost the ability to ambulate at 1 year were significantly older than patients who maintained the ability to ambulate (87.5 vs 76.4 years, P < .05). Patients older than 85 years were more likely to lose the ability to ambulate and to live in a skilled nursing facility at 1 year (P < .01). CONCLUSION Distal femoral periprosthetic fractures have a high morbidity and mortality. Age at time of injury, not treatment rendered, is predictive of ambulatory status and living independence after periprosthetic distal femur fractures.

Open Reduction vs Distal Femoral Replacement Arthroplasty for Comminuted Distal Femur Fractures in the Patients 70 Years and Older

BACKGROUND The ideal management of distal femur fractures in the elderly is unclear. Acute arthroplasty has the theoretical advantage of earlier mobilization. We examined the outcomes of patients 70 years and older who underwent open reduction internal fixation (ORIF) vs distal femoral replacement (DFR) for comminuted, intra-articular distal femur fractures. METHODS A retrospective review of patients with AO/OTA classification 33C distal femur fractures treated with either ORIF or DFR was performed. Outcomes including all-cause reoperation, length of stay, fracture union, postoperative complications, use of ambulatory device and living situation at 1 year, and mortality were evaluated. RESULTS The study cohort included 38 patients: 10 underwent DFR and 28 ORIF. Mean patient age for both cohorts was 82 years. No difference in comorbidities or mechanism of injury was found between groups. The incidence of reoperation was 11% in the ORIF group and 10% in the DFR group. In the ORIF group, the average time to fracture union was 24 weeks, with a nonunion incidence of 18%. Twenty-three percent of ORIF group were wheelchair dependent vs none in the DFR cohort, although not statistically significant. Differences between the groups with respect to all-cause reoperation, living situation or need for ambulatory device at 1 year, and 1-year mortality did not reach statistical significance. CONCLUSION Nearly 1 in 5 patients older than 70 years developed a nonunion after ORIF of an intra-articular distal femur fracture. At 1-year follow-up, all patients in DFR group were ambulatory while 1 in 4 in the ORIF group were wheelchair bound.

Expression of Phosphocitrate-Targeted Genes in Osteoarthritis Menisci

Phosphocitrate (PC) inhibited calcium crystal-associated osteoarthritis (OA) in Hartley guinea pigs. However, the molecular mechanisms remain elusive. This study sought to determine PC targeted genes and the expression of select PC targeted genes in OA menisci to test hypothesis that PC exerts its disease modifying activity in part by reversing abnormal expressions of genes involved in OA. We found that PC downregulated the expression of numerous genes classified in immune response, inflammatory response, and angiogenesis, including chemokine (C-C motif) ligand 5, Fc fragment of IgG, low affinity IIIb receptor (FCGR3B), and leukocyte immunoglobulin-like receptor, subfamily B member 3 (LILRB3). In contrast, PC upregulated the expression of many genes classified in skeletal development, including collagen type II alpha1, fibroblast growth factor receptor 3 (FGFR3), and SRY- (sex determining region Y-) box 9 (SOX-9). Immunohistochemical examinations revealed higher levels of FCGR3B and LILRB3 and lower level of SOX-9 in OA menisci. These findings indicate that OA is a disease associated with immune system activation and decreased expression of SOX-9 gene in OA menisci. PC exerts its disease modifying activity on OA, at least in part, by targeting immune system activation and the production of extracellular matrix and selecting chondroprotective proteins.

Clear-cell chondrosarcoma of the humerus

Clear-cell chondrosarcoma is a rare, low-grade variant of chondrosarcoma characterized by slow growth, low metastatic potential, and a predilection for local recurrence long after treatment. We report an unusually aggressive case of clear-cell chondrosarcoma of the humerus with early metastasis to multiple bony sites including femur, thoracic and lumbar spine, sacrum, and iliac bone. Our purpose is to alert physicians to the sarcomas potential for aggressive behavior, necessitating closer and more frequent followups for early detection and treatment of tumor recurrence and metastasis. We also review the reported imaging and histological features, which may help identify aggressive cases.