Prevalence of insulin resistance in siblings of type 2 diabetics of north west punjabi population.

CONTEXT: Insulin resistance a physiological condition is marked by hyperglycemia and failure of cells to respond to normal action thus hyperinsulinemia. It is prevalent in individuals having genetic predisposition and family history of type 2 diabetes mellitus. Physically inactive individuals having sedentary life style are also at a risk of developing insulin resistance. AIM: The present study was planned to observe the prevalence of insulin resistance or pre diabetes in various age groups of North West Punjabi population. MATERIALS AND METHODS: A total of 400 families comprising of 1159 offsprings of diabetic patients and siblings amongst each were included in the present study. All these 400 families had history of type 2 diabetes mellitus in the present or past generation. Written consent was taken from the head of the family for inclusion in the study. Fasting samples were collected and analysed for Glucose, Glycosylated Hb, complete lipid profile, Insulin and c-peptide. Body mass index, waist hip ratio and HOMA-IR were calculated. Comparison of mean of various parameters was done using student t-test. Analysis of variance (ANOVA) was applied for comparison between groups followed by Bonferroni post hoc analysis. Pearson's correlation method was used for quantitative variables. Statistical significance was defined as p<0.05 (two tailed). RESULTS: Prevalence of impaired fasting glucose both in males and females increased with advancing age. Hyperglycemia along with hyperinsulinemia, hypercholesterolemia and hypertriglyceridemia was observed in individuals having impaired fasting glucose. Individuals belonging to age group of >18-35 years were more prone to insulin resistance as compared to other age groups. CONCLUSION: Insulin resistance at a young age of 18-35 years predisposes these individuals to coronary events. Females in reproductive years are more prone to insulin resistance or pre diabetes as compared to males of the same age group.

Orthopedic applications of silicon nitride ceramics.

Silicon nitride (Si(3)N(4)) is a ceramic material developed for industrial applications that demand high strength and fracture resistance under extreme operating conditions. Recently, Si(3)N(4) has been used as an orthopedic biomaterial, to promote bone fusion in spinal surgery and to develop bearings that can improve the wear and longevity of prosthetic hip and knee joints. Si(3)N(4) has been implanted in human patients for over 3 years now, and clinical trials with Si(3)N(4) femoral heads in prosthetic hip replacement are contemplated. This review will provide background information and data relating to Si(3)N(4) ceramics that will be of interest to engineering and medical professionals.

In vitro testing of Al(2)O(3)-Nb composite for femoral head applications in total hip arthroplasty.

Alumina (Al(2)O(3)) bearings in total hip arthroplasty lead to low wear rates, but catastrophic failure of Al(2)O(3) femoral heads, while rare, remains a concern. In the present work, a composite of Al(2)O(3) and niobium (Nb) was tested in vitro for potential use as an alternative femoral head material in vivo. Dense composite laminates of Al(2)O(3) and Nb were fabricated by hot pressing, and their microstructure and mechanical properties were evaluated. The flexural strength of Al(2)O(3)-Nb laminates in four-point loading was 720+/-40MPa, compared with a value of 460+/-110MPa for Al(2)O(3). Scanning electron microscopy and X-ray diffraction showed a well-bonded interface between the Al(2)O(3) and Nb without measurable formation of an interfacial reaction phase. The interfacial shear strength between Al(2)O(3) and Nb, measured by a double-notched specimen test, was 290+/-15MPa. The feasibility of fabricating prototype femoral heads (32mm in diameter), consisting of an Al(2)O(3) surface layer (2-3mm thick) and a Nb core, by hot pressing was shown. The composite femoral head combined the low wear of an Al(2)O(3) articulating surface with the safety of a ductile metal femoral head.

Evaluation of the efficacy of pulsed electromagnetic field in the management of patients with diabetic polyneuropathy.

AIM: The study was carried out to evaluate and compare the effect of low power, low frequency pulsed electromagnetic field (PEMF) of 600 and 800 Hz, respectively, in management of patients with diabetic polyneuropathy. SETTINGS AND DESIGNS: The study was a randomized controlled trial performed in Guru Nanak Dev University and Medical College, Amritsar, India with different subject experimental design. MATERIALS AND METHODS: Thirty subjects within an age group of 40-68 years with diabetic polyneuropathy stages N1a, N1b, N2a were randomly allocated to groups 1, 2, 3 with 10 subjects in each. Group 1 and 2 were treated with low power 600 and 800-Hz PEMF for 30 min for 12 consecutive days. Group 3 served as control on usual medical treatment of diabetic polyneuropathy (DPN). The subjects with neuropathy due to any cause other than diabetes were excluded. The pain and motor nerve conduction parameters (distal latency, amplitude, nerve conduction velocity) were assessed before and after treatment. STATISTICAL ANALYSIS: Related t-test and unrelated t-test were used for data analysis. RESULTS: Significant reduction in pain and statistically significant (P<0.05) improvement in distal latency and nerve conduction velocity were seen in experimental group 1 and 2. CONCLUSIONS: Low-frequency PEMF can be used as an adjunct in reducing neuropathic pain as well as for retarding the progression of neuropathy in a short span of time.

A review of ceramic bearing materials in total joint arthroplasty.

Bearings made of ceramics have ultra-low wear properties that make them suitable for total hip arthroplasty (THA) and total knee arthroplasty (TKA). When compared to cobalt chrome (CoCr)-on-polyethylene (PE) articulations, ceramics offer drastic reductions in bearing wear rates. Lower wear rates result in fewer wear particles produced by the articulating surfaces. In theory, this should reduce the risk of periprosthetic osteolysis and premature implant loosening, thereby contributing to the longevity of total joints. In addition to ceramics, other alternative bearing couples, such as highly cross-linked PE (XLPE) and metal-on-metal also offer less wear than CoCr-on-PE articulations in total joint arthroplasty. Alumina and zirconia ceramics are familiar to orthopaedic surgeons since both materials have been used in total joints for several decades. While not new in Europe, alumina-on-alumina ceramic total hips have only recently become available for widespread use in the United States from various orthopaedic implant manufacturers. As the search for the ideal total joint bearing material continues, composite materials of existing ceramics, metal-on-ceramic articulations, and new ceramic technologies will offer more choices to the arthroplasty surgeon. The objective of this paper is to present an overview of material properties, clinical applications, evolution, and limitations of ceramic materials that are of interest to the arthroplasty surgeon.

Apolipoprotein modifying effects of statins and fibrate in various age groups of coronary artery disease patients.

These days apolipoproteins especially apo B and apo A I are thought to be better predictors of risk of coronary artery disease as compared to lipids and lipoprotein cholesterol. Lifestyle modification and use of lipid modifying drugs such as statins and fibrates have proven effective in reducing the risk of coronary artery disease. Statins and fibrates are known to possess anti-atherosclerotic properties in addition to lipid modifying effects. Extensive data is available regarding lipid modification especially lowering of low density lipoprotein-cholesterol levels by these drugs. But the data regarding the effect of statins and fibrates, on apolipoprotein levels is scanty. Hence the present study was aimed at assessing the effect of statins (atorvastatin, simvastatin) and fenofibrate on serum apo B and apo A I levels in addition to their lipid modifying effects in various age groups of coronary artery disease patients. One hundred patients suffering from coronary artery disease were randomly assigned to 10 mg atorvastatin, 10 mg simvastatin and 200 mg fenofibrate, separately (without any combination). All the patients were divided into three age groups; group I (35-45 years), group II (46-55 years) and group III (> 55 years). Significant modification was observed in lipid and lipoprotein profile of coronary artery disease patients when treated with these drugs (statins and fibrates). A significant increase in serum apo A I (p < 0.01) and decline in serum apo B levels (p < 0.01) was observed in case of coronary artery disease patients after 16 weeks treatment, though the effect started after 1 month. All the three drugs reduced serum apo B levels in a comparable manner. Fenofibrate increased serum high density lipoprotein-cholesterol and apo A I levels more as compared to statins. It had nearly, proportionate effect in increasing high density lipoprotein-cholesterol and apo A I levels and reducing serum low density lipoprotein-cholesterol and apo B levels while the effect was disproportionate in case of atorvastatin and simvastatin. All the three drugs not only corrected lipid and lipoprotein cholesterol levels but also modified, apolipoprotein levels in a positive direction in coronary artery disease patients. Advancing age had no appreciable effect on the efficacy of these drugs.

Revision of the acetabular component without cement after a previous acetabular reconstruction with use of a bulk femoral head graft in patients who had congenital dislocation or dysplasia. A follow-up note.

BACKGROUND: Revision of an acetabular component that has failed after a total hip arthroplasty in which a bulk femoral head autogenous graft or allograft was used as a structural graft for acetabular reconstruction is an uncommon but complex and challenging procedure. We previously reported the results for seventy hips at an average of 16.5 years after a total hip arthroplasty in which an acetabular reconstruction had been performed with a femoral head graft. In the present study, we evaluated a subset of nine hips from that series that had a subsequent revision of the acetabular component without cement. The purpose of the current study was to assess the usefulness of the bone graft in this revision. METHODS: The nine patients (nine hips) were followed clinically and radiographically for an average of seventy-six months (range, sixty-one to 114 months) after the index revision. In six hips the autogenous femoral head graft previously had been bolted to the lateral side of the ilium, and in one hip the femoral head allograft had been affixed in this manner. In the two remaining hips, the allograft had been placed within the acetabulum. The hips were classified according to the extent of acetabular bone loss, with use of criteria described previously. Three hips had stage-I bone loss; four, stage-II; and two, stage-IIB. A porous-coated hemispherical acetabular component was inserted without cement and fixed with screws in each hip. At least 70 percent of the porous coating was in contact with viable bone. RESULTS: At the time of the latest follow-up after the index revision, all nine acetabular components were functioning well without loosening or osteolysis and none had been revised. The average Harris hip score was 77 points (range, 61 to 98 points) compared with 49 points (range, 27 to 96 points) preoperatively. One hip had had revision of the femoral stem, and another had had exchange of the acetabular liner because of recurrent dislocations. There was no additional resorption of the residual bulk graft that was in contact with the metal shell in any hip. CONCLUSIONS: In this small series of complex acetabular revisions, the healed bulk graft provided valuable additional bone stock for the support of an acetabular component that was inserted without cement. Insertion of the acetabular component into the available bone, which consisted in major part of host bone and in minor part of united revascularized bulk graft, resulted in a well functioning hip after an intermediate duration of follow-up. In all except two hips, the enlarged bone stock allowed insertion of a larger acetabular component than had been used previously.

Polyethylene wear in cases using femoral stems of similar geometry, but different metals, porous layer, and modularity.

In this report, 83 total hip arthroplasties in 75 patients with femoral stems of similar geometry but different metals, porous surfaces, and femoral head-neck design were compared at a mean follow-up of 66 months (range, 40-104 months). One type of acetabular component and polyethylene were implanted in all hips. The femoral stem was monoblock in 25 hips, and in 58 it had a modular head-neck piece; 70 stems had chrome-cobalt heads, and 13 heads were titanium. Equally satisfactory clinical results were obtained with either type of femoral implant (i.e., modular and monoblock). The calculated average annual linear polyethylene wear was significantly higher for the titanium stems with a plasma-spray porous surface and chrome-cobalt head on a Morse taper than the chrome-cobalt, beaded, monoblock stems (0.22 mm/year vs 0.07 mm/year, P < .0001). The prevalence of periprosthetic osteolysis was higher for these modular stems ( 15.7% vs 0%), but this difference was not statistically significant (P = .09). Gross corrosion was present on the taper surfaces of an autopsy-retrieved femoral implant with a modular cobalt-chrome head on a titanium stem. Particles of chromium 3-orthophosphate were present at the taper rim and in the periarticular tissues.

Trochanteric union following revision total hip arthroplasty.

Ninety-nine patients (106 hips) with a trochanteric osteotomy during revision total hip arthroplasty were evaluated at a minimum of 5 years after surgery. Trochanteric reattachment was done with monofilament cobalt-chromium wires. The influence of the following variables on trochanteric union was examined: a prior trochanteric osteotomy, an existing trochanteric nonunion, trochanteric advancement to the lateral femur, use of vertical (in addition to horizontal) wires through the trochanter, and use of a trochanteric mesh. Overall, union occurred in 92 of the 106 trochanters (87%). Fifty-three of 61 trochanters (86.9%) healed after an initial osteotomy, whereas 34 of 38 (89.5%) healed after a repeat osteotomy. Five of the 7 trochanters with an existing nonunion healed, and 5 of 5 trochanters reattached to a bulk allograft healed. Twenty-nine of 36 trochanters (80.5%) reattached to cancellous bone healed, compared with 58 of 65 (89.2%) that were reattached to the lateral femoral cortex. Ninety percent (83/92) of the trochanters reattached in conjunction with use of a chrome-cobalt mesh healed, compared with 64.3% (9/14) of those without (P < .05). Of the variables studied, only the use of mesh was statistically significant. Osteotomy through a previously healed trochanter, advancement of the trochanter to cortical bone, existing trochanteric nonunion, trochanteric reattachment to a bulk allograft, and lack of vertical wires for fixation did not adversely affect the likelihood of obtaining trochanteric union.

Periprosthetic femoral osteolysis around an uncemented nonmodular Moore prosthesis.

Periprosthetic osteolysis is a major problem in total joint arthroplasty surgery today. The particulate debris from ultrahigh-molecular-weight polyethylene, polymethyl methacrylate, and corrosion products from modular connections have been implicated in this process. A case of femoral osteolysis at the tip of a nonmodular Moore prosthesis, in the absence of polyethylene, polymethyl methacrylate, and modular connections, is reported. In the area of osteolysis, histochemical and in situ hybridization techniques established the expression of messenger ribonucleic acid encoding for certain cytokines implicated in bone resorption, preferentially in the area of osteolysis. This case illustrates that the etiology of periprosthetic osteolysis is multifactorial and can occur in the absence of polyethylene, methacrylate, or modular components. All joint implants should be monitored for the development of this complication.

A technique for comparison of leg lengths during total hip replacement.

Leg-length inequality after total hip arthroplasty is not uncommon and can be distressing to the patient. The use of a particular design of Steinmann pin for comparing a patient's leg lengths during total hip arthroplasty is illustrated.

Arthroscopic resection of a chondroblastoma in the knee.

A 13-year-old boy with the diagnosis of osteochondritis dissecans underwent arthroscopic examination of his knee joint. At surgery a cartilaginous mass in the medial femoral condyle was identified. Biopsy samples confirmed the diagnosis of chondroblastoma, which was removed completely through the arthroscope. A second arthroscopic examination of the knee was conducted at 6 months, and showed no residual disease. Clinical and radiographic follow-up of the affected joint 5 years after surgery was satisfactory. Arthroscopic removal of an intra-articular tumor is an attractive treatment alternative, provided the lesion is accessible and there is no suggestion of a malignancy.

A technique for cementing of the patellar component in total knee arthroplasty.

A technique is described for cementing of the patellar component in total knee arthroplasty that involves pressurization of cement into the patellar-component lug holes, which are drilled in the bone prior to cementing the component. A radiographic comparison of cement penetration with this method versus that obtained by using conventional techniques is illustrated.

Calcium and collagen binding properties of osteopontin, bone sialoprotein, and bone acidic glycoprotein-75 from bone.

Calcium binding properties of bone acidic glycoprotein-75, osteopontin, and bone sialoprotein were determined in 10 mM imidazole buffer (pH 6.8), containing either 60 mM KCl or 150 mM NaCl. Proteins assayed were first bound to nitrocellulose to mimic substrate-bound forms in vivo; retention of phosphoproteins was determined through use of radioiodinated tracers. Binding studies were carried out both as a function of calcium concentration and the amount of phosphoprotein. In the presence of 60 mM KCl, bone acidic glycoprotein-75 exhibited the largest calcium binding capacity (139 atoms/molecule at saturation), with bone sialoprotein intermediary (83 atoms/molecule) and osteopontin lowest (50 atoms/molecule). Sites detected for each phosphoprotein exhibited overall binding constants in the 0.5-1.0 mM extracellular range. In 150 mM NaCl and 1-2 mM total calcium, phosphoproteins bound between 72 and 19 mol of calcium/mol with the same relative order. Binding was proportional to amount of phosphoprotein in either salt condition. The presence of 5 mM calcium had a different effect on concentration-dependent binding to type I collagen for each phosphoprotein. Bone acidic glycoprotein-75 alone was found to undergo an unusual calcium-enhanced polymerization reaction, confirmed by light scattering measurements, wherein collagen binding was greatest with polymeric forms. These findings demonstrate that acidic phosphoproteins from bone bind calcium atoms with a range of capacities. Calcium appears to induce conformational changes in bone acidic glycoprotein-75 which influences its self-association and binding to different substrata.

Adrenergic mechanisms contribute to alterations in regional perfusion during normotensive E. coli bacteremia.

The complex role of adrenergic mechanisms in the pathogenesis of sepsis and shock remains incompletely understood. Recent reports have suggested that adrenergic mechanisms may play an important modulatory role in arachidonate metabolism during early sepsis, specifically in the synthesis of the vasoactive metabolites thromboxane A2 and prostacyclin. The purpose of the present set of experiments was to evaluate the extent to which adrenergic mechanisms contribute to early alterations in regional perfusion during Gram-negative bacteremia, using the mixed alpha adrenergic receptor antagonist phenoxybenzamine hydrochloride. Male Sprague-Dawley rats received a 3-hour continuous intraarterial infusion of either saline (n = 7) or 6.6 +/- 0.4 x 10(8) live E. coli colony forming units (n = 7), after which regional perfusion was determined using 51Cr-labelled microspheres (16.5 +/- 0.1 micron). Significant reductions (p less than 0.05) in blood flows to the renal, gastric, cecal, pancreatic, and splenic beds, as well as a reduction (p less than 0.05) in the calculated portal venous flow, were observed in the bacteremic group while mean arterial blood pressure remained unchanged. Further experiments conducted in 14 rats with preexisting alpha adrenergic receptor blockade revealed relative preservation of renal, gastric, cecal, and portal venous blood flows during bacteremia. These data identify alterations in regional perfusion during early E. coli bacteremia occurring before changes in systemic arterial blood pressure, and indicate that adrenergic mechanisms participate in the modulation of such.