Embolism in total arthroplasty or hip fractures, coagulation disorders, such as a variety of ways for the prevention of complications of anticoagulation therapy with medication is being done well. The purpose of this study, a representative of the anticoagulation therapy with enoxaparin and drug rivaroxaban of coagulation tests performed in patients between the two groups was to determine whether statistically significant differences. 47 patients who underwent arthroscopic surgery were randomly divided into two groups to rivaroxaban and enoxaparin group, and we performed coagulation tests before and 5 days after arthroscopic surgery to two drugs groups in order to investigate about the difference in clotting capacity.Introduction
Methods
Recently, the combination of press-fit acetabular cup with ceramic articulation is a widely used for implanting cementless acetabular components and has been shown to provide good initial stability. However, these methods may lead to elevating stresses, changing in the bearing geometries, and increasing wear due to deformation of the cup and insert. In addition, there is a potential for failure of ceramic inserts when a large ball head was used because it should be assembled with shallow thickness of the acetabular cup. For risk reduction of it, we applied direct metal tooling (DMT) based on 3D printing for porous coating on the cup. Due to its capability of mechanical strength, DMT coated cup could be feasible to provide better stability than conventional coating. Therefore, we constructed laboratory models for deformation test simulating an press-fit situation with large ceramic ball head to evaluate stability of the DMT coated cup compared with conventional coated cup. The deformation test was performed according to the test setup described by Z. M. Jin et al. The under reaming of the cavity in a two-point pinching cavity models of polyurethane (PU) foam block (SAWBONES, Pacific Research Laboratories, USA) with a grade 30 were constructed. Titanium plasma spray (TPS) and direct metal tooling (DMT) coated acetabular cups (BENCOX Mirabo and Z Mirabo Cup, Corentec Co. Ltd., KOREA) with a 52 mm size (n=3, respectively) were used for the test. These cups were implanted into the PU foam blocks, and followed by impaction of the inserts (BIOLOX delta, Ceramtec, GE) with a 36/44 size (n=6) into the acetabupar cups as shown in Fig. 1. Roundness and inner diameter of the acetabular cups and inserts were measured using a coordinate measuring machine (BHN 305, Mitutoyo Neuss, GE) in three levels; E2, E3, and E4 (3, 5, and 7 mm below the front face, respectively). Also, these parameters of the acetabular cup were measured in two level; E1 and E5 (5 and 11 mm below the front face) as shown in Fig. 2. Changes in roundness and inner diameter of the cup and insert were measured to evaluate deformation in relation to porous coating on the acetabular cups.Introduction
Materials and Methods
The purpose of this study was to demonstrate postoperative improvement and high satisfaction rates after a surgical approach that includes arthroscopic labral repair only, in patients with borderline dysplasia, without instability. Between September 2009 and December 2011, patients less than 50 years old who underwent hip arthroscopy for symptomatic intra-articular hip disorders, with a lateral center-edge (CE) angle between 20 and 25, were included in this study. Patients with Tönnis grade 2 or greater, hip joint space narrowing, severe hip dysplasia (CE〈20), hip joint instability and Legg-Calve-Perthes disease were excluded. Patient-reported outcome scores, including the modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Arthritis index (WOMAC), and visual analog scale (VAS) for pain were obtained in all patients preoperatively and at 1, 2, and 3 years postoperatively.Introduction
Methods
Recently, a special type of surface pitting found on metal implants was proposed to arise from “inflammatory cell-induced” corrosion (ICI, Figure 1) (1, 2). The actual mechanism of this was unknown, but similar features were suggested to be artefacts of electrocautery damage from revision surgery (3). Under lab conditions and without the influence of any cells, we aimed to reproduce the same surface pits and structures with electrocautery. A polished cobalt-chromium disk (40 mm diameter, 8 mm thick) was marked into 8 sections for various testing conditions (Figure 2a). A stainless steel Bovie tip with a unipolar electrocautery machine (SYSTEM 5000, ConMed, USA) was used at typical surgical coagulation conditions: (70 volt, 120 watts, 562 KHz frequency). We mimicked three types of surgical techniques with the electrocautery: “Dotting” was repeated, on and off, direct surface contact; “Dragging” was constant, direct surface contact; “Hovering” was pausing several millimeters above the surface. We also examined the interplay of these practices on diamond-tip-induced scratches and either dry or wet (normal saline) conditions. High magnification images (Keyence VHX-2000E) were taken after the disk was cleaned with laboratory soap, light mechanical scrubbing, and formalin soak. Coagulation mode generated electrical sparks when dotting/dragging and electrical arcs when hovering. These left seared marks that persisted even after cleaning (Figure 2b). At higher magnification, the surface features were comparable in size and shape to those attributed to ICI (1, 2). Areas wet with saline (Figure 3a) showed an abundance of ringed pits with raised edges that closely resembled those observed in Figure 1. Furthermore we obtained images similar to the phenomenon of “cellular tracks” (Figure 3b) (1). Premade scratches did not influence the pit arrangement but scratches made by the Bovie tip produced the characteristic scratch-associated ICI features as observed on implant retrievals in the past (Figure 3c) (4).Methods
Results
Structural bone allografts are a viable option in reconstructing massive bone defects in patients following musculoskeletal (MSK) tumour resection and revision hip/knee replacements. To decrease infection risk, bone allografts are often sterilised with gamma-irradiation, which consequently degrades the bone collagen connectivity and makes the bone brittle. Clinically, irradiated bone allografts fracture at rates twice that of fresh non-irradiated allografts. Our lab has developed a method that protects the bone collagen connectivity through ribose pre-treatment while still undergoing gamma-irradiation. Biomechanical testing of bone pretreated with our method provided 60–70% protection of toughness and 100% protection of strength otherwise lost with conventional irradiation. This study aimed to determine if the ribose-treated bone allografts are biocompatible with host bone. The New Zealand White rabbit (NZWr) radius segmental defect model was used, in which 15-mm critically-sized defects were created. Bone allografts were first harvested from the radial diaphysis of donor female NZWr, and treated to create 3 graft types: C=untreated controls, I=conventionally-irradiated (33 kGy), R=our ribose pretreated + irradiation method. Recipient female NZWr (n=24) were then evenly randomised into the 3 graft groups. Allografts were surgically fixed with a 0.8-mm Kirschner wire. Post-operative X-rays were taken at 2, 6, and 12 weeks, with bony healing assessed by a blinded MSK radiologist using an established radiographic scoring system. The reconstructed radii were retrieved at 12 weeks and analysed using bone histomorphometry and microCT. Kruskal-Wallis and Mann-Whitney tests were utilised to compare groups, with statistical significance when p<0.05. Radiographic analysis revealed no differences in periosteal reaction and degree of osteotomy site union between the groups at any time point. Less cortical remodeling was observed in R and I grafts compared to untreated controls at 6 weeks (p=0.004), but was no longer evident by 12 weeks. Radiographic union was achieved in all groups by 12 weeks. Histologic and microCT analysis further confirmed union at the graft-host bone interface, with the presence of mineralising callus and osteoid. Histomorphometry also showed the bridging external callus originated from host bone periosteum and a distinct cement line between allograft and host bone was present at the union site. Previous studies have shown that the presence of non-enzymatic glycation end products in bone can impair fracture healing. However, these studies investigated bony healing in the setting of diabetic states. Our findings showed that under normal conditions, ribose pretreated grafts healed at rates similar to controls via mechanisms also seen in retrieved human allografts clinically in use. These findings that grafts pretreated with our method are biocompatible with host bone in the rabbit help to further advance this technology for clinical trials.
Most surgeons that have performed kinematically aligned TKA have noticed an overall better clinical outcome, better motion, better patient satisfaction, and a quicker recovery than their patients treated with mechanically aligned TKA. We prospectively followed all 128 knees who underwent primary total knee arthroplasty. The Lysholm knee Introduction
Materials and Methods
As the proximal femoral bone is generally compromised in failed total hip arthroplasty, achievement of solid fixation with a new component can be technically demanding. Clinical studies have demonstrated good medium-term results after revision total hip arthroplasty using modular fluted and tapered distal fixation stems, but, to our knowledge, long-term outcomes have been rarely reported in the literature. The purpose of this study was to report the minimum ten-year results of revision total hip arthroplasty using a modular fluted and tapered distal fixation stem. We analyzed 40 revision THAs performed in using a modular fluted and tapered distal fixation stem (Fig. 1) between December 1998 and February 2004. There were 11 men (12 hips) and 28 women (28 hips) with a mean age of 59 years (range, 38 to 79 years) at the time of revision THA. According to the Paprosky classification of femoral defects, 5 were Type II, 24 were Type IIIA, and 11 were Type IIIB. An extended trochanteric osteotomy was carried out in 21 (52%) of the 40 hips. Patients were followed for a mean of 11.7 years (range, 10 to 15 years).Introduction
Materials & Methods
The purpose of the present study was to compare functional outcomes of medial unicompartmental knee arthroplasty (UKA) in patients with lateral meniscal lesion (LM (+) group) in the preoperative MRI and those without lateral meniscal pathology (LM (−) group) and to evaluate the effect of lateral meniscus lesion in preoperative MR on functional outcomes after UKA. The outcomes of 66 knees (LM (+) group) were compared to the outcomes of 54knees(LM (−) group)with a median follow-up of 28 month(range 24–36 months). Clinical outcomes including KS object score, KS pain score, lateral side pain, physical exam for lateral meniscal lesion and squatting ability. Radiological parameters (mechanical axis and component position) were compared and their effects on functional outcomes were evaluated at the final follow-up visits.Purpose
Methods
Patients with osteonecrosis of the femoral head are typically younger, more active, and often require high rates of revision following primary total hip arthroplasty. However, outcomes of revision hip arthroplasty in this patient population have been rarely reported in the literature. The purpose of this study was to report the intermediate-term clinical and radiographic outcomes of revision hip arthroplasty in patients with osteonecrosis of the femoral head. Between November 1994 and December 2009, 187 revision hip arthoplasty were performed in 137 patients who had a diagnosis of osteonecrosis of the femoral head. Exclusion criteria included infection, recurrent instability, isolated polyethylene liner exchange, and inadequate follow-up (less than 3 years). The final study cohort of this retrospective review consisted of 72 patients (75 hips) with a mean age of 53.3 years (range, 34 to 76). Components used for the acetabular revision included a cementless porous-coated cup in 58 hips and an acetabular cage in 2 hips. Components used for the femoral revision included a fully grit-blasted tapered stem in 30 hips and a proximally porous-coated modular stem in 9 hips. The mean duration of follow-up was 7 years (range, 3 to 17).Introduction
Materials & Methods
Cementless arthroplasty has been widely used for younger patients with osteoarthritis and other joint pathology. Cementless arthroplasty will be required to porous surface which is to similar to the trabecular bone for bone ingrowth. Titanium Plasma Spray (TPS) has been worldwide used for the porous coating method on arthroplasty. However, TPS coating is limited that would not to establish optimal porosity for bone ingrowth due to arbitary position of melted powder by plasma gas on substrate. Therefore, it is reported coating detached from its substrate (i.e. arthroplasty) is induced implant loosening. Thus, a novel Laser-aided Direct Metal Tooling (DMT) based on Additive Manufacturing (AM) was developed to overcome these limitations. In this study, we were done to assess stereological analysis, static tensile, shear, abrasion test, and physical analysis for evaluation of the efficacy of DMT which was newly-developed coating technology. Then, mechanical characteristics of DMT coating were compared to commercial TPS coating's. First, porosity of the DMT coating was evaluated using Microphotography and Scanning Electron Microscopy (SEM), as described in Figure 1. Static tensile and shear test for assessment of mechanical characteristic in relation to the DMT and TPS coating specimens were conducted on the basis of ASTM F1147 and F1044 using universal testing machine (Endolab®, Servohydraulic Test Frame, DE). Maximum tensile strength and maximum shear strength were evaluated for each specimen (n=5). Abrasion test was performed based on ASTM F1978 using Taber® Rotary Platform Abraser Model 5135 (TABER®Industries, USA). Abrasion losses for each specimen (n=6) were measured at 2, 5, 10, and 100 cycles, respectively.Introduction
Materials and Methods
Modern ceramic-on-ceramic bearings have become attractive alternatives to conventional polyethylene due to their low wear and minimal particle production. However, ceramic-on-ceramic implants have been associated with ceramic fracture and squeaking. To address these issues, large ceramic heads with a titanium-alloy sleeve have been introduced although limited data are available on their clinical outcomes. The purpose of this study was to report the midterm results of primary total hip arthroplasty using a 32mm with a titanium-alloy sleeve. We reviewed 245 patients who had 274 total hip arthroplasties with a 32 mm ceramic head with a titanium-alloy sleeve and had been followed for more than 5 years (average, 6.5 years; range, 5–9 years). The mean patient age at the time of surgery was 55.1 years (range, 16–82 years). All operations were performed at a single center. All of the ceramic implants were hot isostatic pressed, laser-marked, proof-tested third-generation alumina (Fig. 1). We determined the implant survival, Harris hip scores, incidence of ceramic fracture or noisy hips, and presence of osteolysis.Introduction
Materials & Methods
The purpose of this study was to demonstrate postoperative improvement and high satisfaction rates after a surgical approach that includes arthroscopic labral repair only, in patients with borderline dysplasia, without instability. Between September 2009 and December 2011, patients less than 50 years old who underwent hip arthroscopy for symptomatic intra-articular hip disorders, with a lateral center-edge (CE) angle between 20 and 25, were included in this study. Patients with Tönnis grade 2 or greater, hip joint space narrowing, severe hip dysplasia, hip joint instability and Legg-Calve-Perthes disease were excluded. Patient-reported outcome scores, including the modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Arthritis index (WOMAC), and visual analog scale (VAS) for pain were obtained in all patients preoperatively and at 1, 2, and 3 years postoperatively.Purpose
Methods
Highly cross-linked polyethylene has been introduced to decrease osteolysis secondary to polyethylene wear debris generation, but there are few long-term data on revision total hip arthroplasty using highly cross-linked polyethylene liners. The purpose of this study was to report the long-term radiographic and clinical outcomes of a highly cross-linked polyethylene liner in revision total hip arthroplasty. We analyzed 63 revision total hip arthoplasties that were performed in 63 patients using a highly cross-linked polyethylene liner between April 2000 and February 2005. Of these, nine died and four were lost to follow-up before the end of the 10-year evaluation. Thus, the final study cohort consisted of 50 patients (50 hips). There were 26 males and 24 females with a mean age at time of revision total hip arthoplasty of 53 years (range, 27–75 years). Mean duration of follow-up was 11 years (range, 10–14 years).Introduction
Materials & Methods
The purpose of this study was to evaluate the postoperative maximal flexion of Robotic assisted TKA which does not increase the posterior condylar offset after surgery and compare CT and conventional radiography in measuring the posterior condylar offset changes. 50 knees of 37 patients who underwent Robotic TKA and underwent follow-up minimal one year were evaluated. CT based preoperative surgical planning system was designed not to increase posterior condylar offset (PCO) after surgery. Maximal flexion angle of the knee was evaluated at 1 year after surgery. The change in PCO and joint line on x-ray and CT were evaluated.Purpose
Materials and method
