Introduction

One of the important criteria of the success of TKR is achievement of the Flexion ROM. Various factors responsible to achieve flexion are technique, Implant and patient related. Creation of the Posterior condylar offset is one such important factor to achieve satisfactory flexion.

Aim

To correlate post op femoral condylar offset to final flexion ROM at 1 yr. post op.

Introduction

Fixed flexion isolated or along with varus / valgus is a common deformity for patients undergoing TKR. For a satisfactory outcome and normal gait post op FFD needs to be corrected completely. An additional distal femoral resection may be necessary to equalize the extension gape to correct Gr 2 FFDs.

Aim

To demonstrate full FFD correction without resecting extra distal Femur.

Introduction

Various implant designs and bearing surfaces are used in TKR. The use of All Poly Tibia and poly moulded on Tibial metal base plate has been in practice since long. Recently due to the reports on wear and osteolysis in modular articulations, these components have generated significant interest.

Aim

To report early medium term results in elderly (>70 years) patients.

Objective

To investigate the biomechanical basis and report preliminary clinical efficacy of eccentric rotational acetabular osteotomy (ERAO) when treating developmental dysplasia of the hip (DDH).

Methods

Biomechanical model of the hip joint was established on cadaveric hips. After performed ERAO on the biomechanical model, we explored the impact of this surgery on biomechanics of the hip joint. Meanwhile, we reported postoperative follow-up cases who underwent ERAO in our hospital between November 2007 to July 2012. A total of 14 patients (15 hips) were reported, including 4 males and 10 females, mean age was 30 years old. Harris hip score was defined as clinical evaluation standard and radiographic assessment was based on the measurement and further comparison of pre- and post-operative AHI (Acetabular-head index), CE angle (Center-edge angle) and Sharp angle.

Objective

To explore whether good postoperative alignment could be obtained through simple individual valgus resection angle using common instruments in total knee arthroplasty with lateral bowing femur.

Methods

Data of 46 TKAs with lateral bowing femur were collected prospectively, the center of the femoral intercondylar notch was the fixed drilling hole whether preoperative planning or intraoperative implementing. The intramedullary rod was put into the femur as deep as possible, until completely entrance or the distal point of the rod contact with the lateral cortical bone of the femur, which prevent the further entrance of the rod. Individual valgus resection angle ranging from 7°to 9°was performed according to preoperative planning, followed by meticulous assessment of matching between cutting surface and valgus resection angle. Postoperative hip-knee-ankle (HKA) angle?medial tibial plate angle and position of lower extremity alignment passing through the tibial plate were measured.

Introduction

The patients with hip fracture have a general complication including heart disease. The heart echo is useful for the preoperative evaluation of cardiac function.

Objectives

The purpose of this study was to assess the relationship between echocardiographic findings and postoperative walking ability of patients with hip fracture.

Background

Venous thromboembolisms are serious complications of arthroplasty of the lower extremities. Although early ambulation and active leg exercise is recommended, postoperative patients with surgical pain have difficulty in moving their legs. Therefore, we developed a novel leg exercise apparatus (LEX) to facilitate active leg movement even during the early postoperative period (Fig 1). LEX is a portable apparatus that allows patients to actively move their legs while in the supine position. LEX enables dorsiflexion, plantar flexion, combined eversion and inversion of the ankle, and multi-joint movement of the leg.

Objectives

To describe how LEX facilitates active movement of the leg and thereby increases venous flow in the lower extremities.

Background

The aim of this study was to evaluate causes and results of revision surgery in unstable total knee arthroplasties.

Methods

We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment according to its cases. Stress radiographs, postoperative component position and joint level were measured. Clinical outcomes were assessed using the score and range of motion of the Hospital for Special Surgery (HSS).

Purpose

To evaluate the results of reverse total shoulder arthroplasty for complicated proximal humerus fractures in old ages.

Materials and Methods

We retrospectively evaluated 13 cases who underwent reverse total shoulder arthroplasty for proximal humerus fracture, fracture-dislocation and nonunions of the fractures. Mean age was 77(68–87)years old and mean follow-up period was 15.2(12–26)months. four part fractures of proximal humerus in 7 cases, fracture-dislocation in 3 cases, locked dislocation with greater tuberosity in 2 cases, nonunion with defiency of rotator cuff in 1 case were included. We evaluated mean ASES, mean UCLA, mean KSS, mean SST and mean range of motion(ROM).

Purpose

We may consider total knee arthroplasty on one knee and unicompartmental knee arthroplasty on another knee when the patient has different grade osteoarthritis on one knee and opposite knee. Both total knee and unicompartmental knee arthroplasty had been reported as excellent clinical results, but there can be different results and different preference if the same patient undergo operation of simulataneous total knee and unicompartmental knee. We performed total and unicompartmental knee arthroplasty and pretend to report results of the clinical and radiological results and rationale of the operation.

Materials and Methods

From Marth 2007 to February 2014, 23 patients, 46 knees that underwent total knee arthroplasty and unicompartmental knee arthroplasty on knees with different osteoarthritis grade in same person enrolled in this study(Fig. 1). The mean age was 64.4 years old(range:55–75) and mean follow-up period was 25.1 months(range:13–72).

Purpose

The purpose of this study is toevaluate the clinical and radiologic results after high flexiontotal knee arthroplasty, Lospa^®(Corentec Inc.) with 10mm cutting of posterior femoral condyle and LPS-Flex^®(Zimmer Inc.) with 12.5mm cutting of posterior femoral condyle.(Fig. 1)

Materials and Methods

We prospectively compared 205 knees in 128 patients who underwent arthroplasty usingLospa^®(groupA) and 63 knees in 48 patients who underwentarthroplasty using NexGen LPS-Flex^®(group B) from September 2010 to March 2012 at Department of Orthopaedic Surgery, Sun General Hospital (Daejeon, Korea). Mean follow-up period was 33 months(24–42) in group A and 33months(23–45) in group B, and mean age was 69.5 in group A, 70.4 in group B. The radiologic analysis included the change of mechanical axis deviation and femoro-tibial angle, implant position (α,β,γ,δ)(Fig 2). The clinical results were evaluated according to Hospital for special surgery (HSS), Knee society score (KSS), and range of motion.

Purpose

When we perform total knee arthroplasty (TKA), the accurate osteotomy and implant setting is important as follows to improve long-term results. As means to perform osteotomy exactly, patient specific surgical instruments (PSI) patient specific surgical instruments planning based on pre-operative MRI (Signature, Materialise) and Image-free navigation system (Navi: Knee unlimited; BrainLAB) exist. However, there is not the report to compare which is exact for the same patient at the same time using two methods. We report to compare the osteotomy plans by two methods.

Materials

Nine cases of TKA (Vanguard Complete Knee System, PS, BIOMET) operated on by one operator in our hospital from October 2012 to September 2013. 78.0 years average age (71–81 years old), sex was 6 cases women, 3 men.

Introduction

In most cases of revision acetabular total hip arthoplasty (THA), some degree of bone loss will be accompanied. If the bone loss is massive, the management of bone defect is more challenging problem. We consider that using cementless accetabular cup for revision acetabular reconstruction is good indication when stable interface fit between the acetabular cup and bone is achieved. The purpose of this study is to review the result of revision hip arthroplasty using cementless acetabular cup with and without bone graft.

Materials and methods

Between 1998 and 2012, 65 revisions using cementless acetabular cup (Mallory-Head 4 Finned component) were performed in 64 patients, whose mean age was 64.9 years. The cases of revision are aseptic loosening (53 joints), and infection (12 joints). All patients were followed up for a minimum period of 24.0 months (mean, 84 months) and were divided into two groups as follows: in group A, revisions without bone graft (28 joints); in group B, revisions with bone graft (37 joints). We compared clinical and radiographical results of group A with group B.

INTRODUCTION

Metallic ion release may be related to bearing surface wear and thus serve as an indicator of in-vivo performance of metal on metal (MOM) articulations.

OBJECTIVES

Compare large head MOM hip components with modular MOM and metal on polyethylene (MOP) to determine their relative effects on serum metal ion levels.

Introduction

Total ankle replacement (TAR) has been used as a surgical intervention for arthritis since the 1970s. However, unlike clinically successful hip and knee replacements, TARs are renowned for extensive contraindications to surgery and high failure rates with an average of 83% survival at 5 years. The majority cite aseptic loosening as the reason for failure. The aim of this study wais to analyse retrieved TARs visually and through interferometry to identify potential the failure mechanisms associated with these devices.

Methods

Retrieved total ankle replacements (n=11) from consecutive revision surgeries carried out at Chapel Allerton Hospital, Leeds between August 2012 and January 2014, were collected for study at the University of Leeds, under an NRES approved procedure (09/H1307/60).

The bearing surfaces of the samples were visually inspected for evidence of damage and wear. The bearing surfaces between the tibial component and the flat surface of the polyethylene insert were then examined using a scanning white light interferometer (NP Flex, Bruker, USA). It was not possible to characterise the talar bearing surface or the inferior polyethylene surface at this stage through interferometry due to the curvature of the surface. The components were aligned and five sections on each of the surfaces measured. These sections represented; anterior-medial, anterior-lateral, posterior-medial, posterior lateral and central regions of the bearing surfaces. 3D roughness values were recorded, and the mean 3D surface roughness compared between implants. Measurements were taken on the medial and lateral aspects of the bearing surfaces to investigate whether damage was location specific. A coefficient of determination was calculated to assess the relationship between implantation time and surface roughness.

Introduction

In order to reduce polyethylene wear and incidence of osteolysis, and improve the long-term durability of total hip arthroplasty (THA), highly cross-linked polyethylene was introduced for clinical use in substitution for conventional polyethylene. We performed 35 cementless THAs between December 2000 and February 2002, and cross-linked polyethylene was used in these surgeries. The purpose of this study is to research linear wear rate of these hips, and to find the risk factor for high wear rate.

Patients and Methods

32 hips (26 patients) among the 35 could be evaluated at more than 10 years postoperatively. One hip required reoperations due to infection at 8 years postoperatively, and two were lost to followup in less than 10 years. There were 2 males and 24 females, and the observation period was 11.4 years in average (range 10?13 years). The age at the time of operation was 49.4 years in average (range 24?67 years), and body mass index was 22.4 in average (15?34). We used AHFIX total hip prostheses (KYOCERA Medical Corporation) for both acetabular and femoral replacement, and 22 mm Zirconia head was used in all cases. The median cup diameter was 46 mm (range 42?50). Osteolysis and loosening of the implant was evaluated on the anteroposterior radiograph of the hip. Using software for wear measurement (Hip Analysis Suite), linear wear rate and cup inclination angle were measured. Correlation between linear wear rate and age, BMI, cup inclination angle, and cup diameter was investigated using correlation coefficient.

Introduction

Varus malpositioning of femoral stems has been recognised as a poor prognostic feature with regard to loosening and failure of cemented composite beam implants, but there have been no published results of the long-term effect on taper-slip designs.

Objectives

To determine the results of varus placement of a polished triple tapered femoral stem.

Introduction

Traditionally it has been thought that the use of a small diameter femoral head in conjunction with a posterior surgical approach would result in a high rate of dislocation. We present the results of a consecutive series of 350 total hip replacements performed using a 22mm femoral head and a standard posterior approach, with prospective data collection.

Objective

To determine the outcome of total hip replacement using small diameter heads via a standard posterior approach.

Background

Stability of total knee arthroplasty (TKA) is dependent on correct and precise rotation of the femoral component. Multiple differing surgical techniques are currently utilized to perform total knee arthroplasty. Accurate implant position have been cited as the most important factors of successful TKA. There are two techniques of achieving soft gap balancing in TKA; a measured resection technique and a balanced gap technique. Debate still exists on the choice of surgical technique to achieve the optimal soft tissue balance with opinions divided between the measured resection technique and the gap balance technique. In the measured resection technique, the bone resection depends on size of the prosthesis and is referenced to fixed anatomical landmarks. This technique however may have accompanying problems in imbalanced patients. Prediction of gap balancing technique, tries to overcome these fallacies. Our aim in this study was twofold: 1) To describe our methodology of ROBOTIC TKA using prediction of gap balancing technique. 2) To analyze the clinico-radiological outcome our technique comparison of meseaured resection ROBOTIC TKA after 1year.

Methods

Patients that underwent primary TKA using a robotic system were included for this study. Only patients with a diagnosis of primary degenerative osteoarthritis with varus deformity and flexion deformity of were included in this study. Patients with valgus deformity, secondary arthritis, inflammatory arthritis, and severe varus/flexion deformity were excluded. Three hundred ten patients (319 knees) who underwent ROBOTIC TKA using measured resection technique from 2004 – 2009. Two hundred twenty (212 knees) who underwent ROBOTIC TKA using prediction of gap balancing technique from 2010 – 2012. Clinical outcomes including KS and WOMAC scores, and ranges of motion and radiological outcomes including mechanical axis, prosthesis alignments, flexion varus/valgus stabilities were compared after 1year.

Background

The most important factors affecting the outcome of a TKA are restoring the normal mechanical axis and achieving optimum soft tissue balance. In the measured resection technique may have accompanying problems in imbalanced patients. Secondly individual variability of the reference points may affect the alignment of the bony cuts and thereby the alignment of the implant. The gap balance technique blends the soft tissue balance with the bony cuts and tries to overcome this problem. However proponents of the measured resection technique argue that no consideration is given to the coronal and rotational alignment of the femoral component in the gap balance technique. The ligament specific navigation assisted gap balance technique, tries to overcome these fallacies. The lateral ligaments and soft tissues act as a reference against which the medial soft tissues are balanced. Thus the reference becomes individualized and any variability is taken care of. Navigation assistance ensures control of the coronal and rotational alignment of the femoral component. The aim of the present study was two fold: - To describe our methodology of ligament specific navigation assisted gap balance technique and analyze the clinico-radiological outcome of our technique over an eight year follow up.

Methods

79 patients (98 knees) with primary osteoarthritis with varus deformity and flexion deformity of were followed up for eight year duration. After obtaining an optimum gap balance and neutral axis in extension, tibial osteotomy perpendicular to the mechanical axis in both the coronal and sagittal planes was done. At this stage joint gaps were distracted in extension and 90â�° flexion. Based on the gap values patients were classified into three groups. Group 1 was the balanced group with flexion extension gap difference ≤2mm, group 2 was the flexion tight group with flexion gap smaller than the extension gap by ≥3mm and group 3 was the extension tight group with the extension gap smaller than the flexion gap by ≥3mm. Thereafter flexion gap balance was achieved only by adjusting the cutting levels of the distal and posterior condyles and adjusting the axial rotation of the femoral component without any further soft tissue release. Intraoperative navigation readings were recorded. All patients were followed clinico-radiologically at 1, 4, and 8 years post operatively.

Introduction

Bone loss in the distal femur and proximal tibia is frequently encountered with both complex primary and revision knee replacement surgery. Metaphyseal sleeves provide a good option for enhanced fixation in managing such defects on both the tibia and femur. We present our results in 48 patients (50 knees) with a minimum 12 month follow up (range 12 to 45).

Methods

48 patients (50 knees) who had revision knee arthroplasty for either septic or aseptic loosening. All were graded Type II or III using the Anderson Orthopaedic Research Institute (AORI) grading system of both femoral and tibial defects. A large portion of aseptic loosening revisions were for extreme osteolysis of a bicondylar knee prosthesis.

Introduction

Total hip replacement (THR) is a very common procedure performed for the treatment of osteoarthritis of the hip. The aim of THR is to restore function and quality of life of the patients, by restoring femoral offset, leg length, centre of rotation, and achieving stability, to avoid dislocation postoperatively.

Method

We aimed to perform preoperative assessment of femoral offset on anteroposterior (AP) radiographs of the hip, and on corresponding CT scans, for patients undergoing primary THR. Patients were positioned according to a standardised protocol prior to obtaining radiographs of the hip and CT scan. Inter- and intra-observer reliability was evaluated between 3 observers of differing levels of seniority – an orthopaedic trainee, a fellow, and a consultant. CT scan measurements of offset were performed by one consultant radiologist. The researchers measuring radiographic offset were blinded to the results of the CT measurements.

Introduction

There are conflicting views when assessing the best imaging modality by which to assess long leg alignment pre and post operatively for patients’ receiving primary total hip replacements. It has been a long standing standard that long-leg radiographs are used for measuring and interpreting alignment of the lower limb, but recently it has been suggested that CT imaging may be a better option for this assessment.

Methods

Patients awaiting total knee replacement surgeries were invited to participate in this clinical trial. 120 participants’ consented and completed both pre and post-operative long-leg radiographs, and lower limb CT scans. Long leg radiographs were analysed and measured by senior orthopaedic surgeons pre and post-operatively, while CT scans were analysed using the perth protocol method by trained radiologists. Mechanical alignment of the lower limb was calculated using both imaging modalities, the CT “scout” scan was used for the measurement of the mechanical alignment.

Pre-operatively the patients had their imaging performed between 1 year and 1 week pre-operatively, and following surgery their imaging was standardised to 6 months post-operatively. For long leg radiographs, patients were asked to stand with their feet shoulder width apart and toes forward facing (on occasion deformities would not allow for this stance, and they were asked to adopt this stance to the best of their ability).

Introduction

Increased accuracy of pre-operative imaging in patient-specific instrumentation (PSI) can result in longer-term savings, and reduced accumulated dose of radiation by eliminating the need for post-operative imaging or revision surgery. The benefits and drawbacks of CT vs MRI for use in PSI is a source of ongoing debate. This study reviews all currently available evidence regarding accuracy of CT vs MRI for pre-operative imaging in PSI.

Methods

The MEDLINE and EMBASE databases were searched between 1990 and 2013 to identify relevant studies. As most studies available focus on validation of a single technique rather than a direct comparison, the data from several clinical studies was assimilated to allow comparison of accuracy. Overall accuracy of each modality was calculated as proportion of outliers >3 % in the coronal plane.

Introduction

Implant stability immediately after implantation is vital for long term success and improvement in patient outcomes for total hip arthroplasty (THA). Of the many factors that influence stability and resistance to migration for press-fit metaphaseal-fixed stems, this work attempted to evaluate the effect of distal stem taper angle on initial stem axial stability. Two THA stem designs having a distal taper angle of 3.5° and 5° were evaluated with cadaveric specimens with a simulated walking gait while stem motion was measured with respect to the periprosthetic bone.

Methods

Introduction

Neck-stem corrosion has been associated with Adverse Local Tissue Reaction (ALTR) in dual-taper femoral stems. Several diagnostic tests, of varying specificity and sensitivity, are used to identify ALTR. The purpose of this study was to document the clinical presentation, diagnostic workup and surgical findings in a large cohort of patients with dual modular stems, and use this information to propose an evaluation protocol that assists surgical decision-making.

Methods

This is a single center, single surgeon's retrospective case series of 38 patients who underwent 42 primary total hip arthroplasty (THA) with a dual-taper femoral components between March 2010 and May 2011 The evaluation included clinical exam, hip radiographs, labs including serum metal ion levels, metal artifact reduction sequence magnetic resonance imaging (MARS MRI), and fluoroscopic hip aspiration with qualitative and quantitative assessment of synovial fluid. Each hip aspirate was classified into Class 1 (clear, <10cc), 2(brown, clear, >10cc), or 3 (cloudy, turbid, viscous). 20 patients to date have undergone revision THA.

Introduction

The goal of tibial tray placement in total knee arthroplasty (TKA) is to maximize tibial surface coverage while maintaining proper rotation. Maximizing tibial surface coverage without component overhang reduces the risk of tibial subsidence. Proper tibial rotation avoids excess risk of patellar maltracking, knee instability, inappropriate tibial loading, and ligament imbalance. Different tibial tray designs offer varying potential in optimizing the relationship between tibial surface coverage and rotation. Patient specific instrumentation (PSI) generates customized guides from an MRI- or CT-based preoperative plan for use in TKA. The purpose of the present study was to utilize MRI information, obtained as part of the PSI planning process, to determine, for anatomic, symmetric, and asymmetric tibial tray designs, (1) which tibial tray design achieves maximum coverage, (2) the impact of maximizing coverage on rotation, and (3) the impact of establishing neutral rotation on coverage.

Methods

In this prospective comparative study, MR images for 100 consecutive patients were uploaded into Materialise™ PSI software that was used to evaluate characteristics of tibial component placement. Tibial component rotation and surface coverage was analyzed using the preoperative planning software. Anatomic (Persona™), symmetric (NexGen™), and asymmetric (Natural-Knee II™) designs from a single manufacturer (Zimmer™) were evaluated to assess the relationship of tibial coverage and tibial rotation. Tibial surface coverage, defined as the proportion of tibial surface area covered by a given implant, was measured using Adobe Photoshop™ software (Figure 1). Rotation was calculated with respect to the tibial AP axis, which was defined as the line connecting the medial third of the tibial tuberosity and the PCL insertion.

Background

To prevent excessive tension on the posterior cruciate ligament (PCL) in cruciate-retaining total knee arthroplasty (CR-TKA), some knee prosthesis-systems offer the option of creating a posterior slope for the tibial polyethylene insert. Vanguard® Complete Knee System offers two different types of tibial bearing for CR

-TKA. CR Lipped Bearing (LB) has a slightly raised posterior lip, whereas CR Standard Bearing (SB) is recessed downward at the posterior margin and has 3° posterior slope. The objective of this study was to investigate the effect of the tibial bearing slope on PCL load using the original devise in vivo conditions.

Material and Methods

Twenty osteoarthritic varus knees were included in this study. After implantation of the trial components, PCL stiffness was measured using the original tension analyzer intra-operatively. Elastic modulus of PCL was calculated at 90 and 120 degrees knee flexion on two types of bearing surface.

Introduction

Various methods to manage medial tibial defects in primary total knee arthroplasty (TKA) have been described. According to Vail TP, metal augmentation is usually indicated for defect depth of >10 mm of the medial tibial plateau. The outcomes of metal augmentation have been described as excellent. Nevertheless, we believe that it is mandatory to preserve as much of the bone as possible for future revision surgeries. Therefore, we performed autologous impaction bone grafting even for large bone defects (defect depth of ≥10 mm) in primary TKA. The objectives of this study are to describe our bone grafting technique in detail and to assess the radiological outcomes of the grafted bone.

Methods

Between 2003 and 2011, 26 TKAs with autologous impaction bone grafting for ≥10 mm medial tibial defects were performed. The preoperative diagnoses were osteoarthritis in 17 knees, rheumatoid arthritis in 2 knees, osteonecrosis of the medial tibial condyle in 6 knees, and Charcot's joint in 1 knee. The average mediolateral width and depth of the medial tibial defects, measured after the horizontal osteotomy of the tibial articular surface, were 17.8 mm (range, 10–25 mm) and 12.0 mm (range, 10–23 mm), respectively. The average patient age at surgery was 73.2 years (range, 56–85 years). The patients were followed up for an average of 55 months (range 27–109 months).

Bone grafting technique: Multiple drill holes (white arrow) were made on the floor of the defect (A) and a morselized cancellous bone was impacted using the grip end of a metal hammer (white asterisk) and firm manual pressure to fill the defect. Thus, the firm impaction prevented bone cement from entering the space between the graft and the tibial host bed. An assistant's index finger (black asterisk) was used as a bank (B). The tibial component was fixed on the grafted bone (white asterisk) with bone cement (C). Internal fixation devices were not required, and stem extension was used in only Charcot's joint (defect depth=23 mm). Aftertreatment was the same as that for the usual TKAs without bone defects.

Introduction

The Flexible Nichidai Knee (FNK) System (Nakashima Medical, Japan) was designed to fit Asian knees. Especially, the posterior stabilized(PS) prosthesis was designed as semi-constrained posterior stabilized system that had a large tibial post and femoral articulation. We hypothesized that the semi-constrained PS implant design would have a positive influence on vivo kinematics after total knee arthroplasty (TKA).

Materials and Methods

A total of 16 patients (21 knees) who had undergone TKA using PS implant were randomly recruited from our database. Of the 16 patients, all patients were women. Fourteen patients had osteoarthritis and 2 patients had rheumatoid arthritis. The average age was 72.3± 9.5 years, and the average postoperative duration was 23.4 ± 19.3 months. The subject performed sequential deep knee bends under WB from 0° to maximum flexion under fluoroscopic monitoring in the sagittal plane. Conversely, under NWB, the patient sat on a chair and was asked to perform active assisted knee flexion. To estimate spatial position and orientation of the artificial knee prosthesis, a 2D to 3D registration technique was used. We evaluated knee range of motion, femoral axial rotation relative to the tibial component, and anteroposterior translation of the femorotibial contact point for both medial and lateral sides. Closest distances between femoral cam and tibial post engagement were measured,

Introduction & aims

Different racial groups show variations in femoral morphometry. Femoral anteroposterior measurement and mediolateral measurement are key variables in designing femoral implant for TKR. Their aspect ratio determines the shape and mediolateral sizing for the proper patellofemoral tracking and uniform stress distribution over the resected distal femoral surface.

Method

We reviewed the current literature in December 2013 in common medical databases including the Cochrane Library, PubMed and Medline. Keywords included combinations of: Anthropometry, Knee, Arthroplasty, Femur, Morphometry, Geometry. We selected papers including femoral morphometric data collected from populations of different ethnic origins. Papers covered populations in the USA, China, Germany, Thailand, Korea, India, Japan and Malaysia.

Backgrounds

Most of in vivo kinematic studies of total knee arthroplasty (TKA) have reported on varus knee. TKA for the valgus knee deformity is a surgical challenge. The purposes of the current study are to analyze the in vivo kinematic motion and to compare kinematic patterns between weight-bearing (WB) and non-weight-bearing (NWB) knee flexion in posterior-stabilized (PS) fixed-bearing TKA with pre-operative valgus deformity.

Methods

A total of sixteen valgus knees in 12 cases that underwent TKA with Scorpio NRG PS knee prosthesis operated by modified gap balancing technique were evaluated. The mean preoperative femorotibial angle (FTA) was 156°±4.2°. During the surgery, distal femur and proximal tibia was cut perpendicular to the mechanical axis of each bone. After excision of the menisci and cruciate ligaments, balancer (Stryker joint dependent kinematics balancer) was inserted into the gap between both bones for evaluation of extension gap. Lateral release was performed in extension. Iliotibial bundle (ITB) was released from Gerdy tubercle then posterolateral capsule was released at the level of the proximal tibial cut surface. If still unbalanced, pie-crust ITB from inside-out was added at 1 cm above joint line until an even lateral and medial gap had been achieved. Flexion gap balance was obtained predominantly by the bone cut of the posterior femoral condyle. Good postoperative stability in extension and flexion was confirmed by stress roentgenogram and axial radiography of the distal femur. We evaluated the in vivo kinematics of the knee using fluoroscopy and femorotibial translation relative to the tibial tray using a 2-dimentional to 3-dimensional registration technique.

Introduction

In total knee arthroplalsties, there are risks of revision surgeries because of aseptic loosening, polyethylene wear, and metal component breakage. The data such as model, type, size, and manufacturing companies are required at the time of revision surgeries. However, it is sometimes difficult to acquire such data due to patient's change of address and the elimination and consolidation of hospitals in the long-term. Therefore, we try to use the Radio Frequency IDentification (RFID) in the total knee joint system.

Materials and methods

The FerVID family (Fujitsu Co. Ltd., Tokyo, Japan) was prepared as the RFID tag. It was radio-resistant below the dose of 50kGy, which allowed gamma sterilization. The RFID tags were embedded into the anterior side of GUR 1050 UHMWPE inserts and 0.3wt% vitamin E blended UHMWPE. The UHMWPE inserts were manufactured by thecompression molding method at the maximum temperature of 220°C and the maximum compressive force of 245kgf/cm². The manufactured inserts were implanted in fresh cadaveric knees. The tibial base plate was made of Ti6Al4V. The femoral components were made of Co-Cr-Mo or Ti-6Al-4V. Communication Performance was measured with the interrogator (DOTR-920 MHz-band, Tohoku Systems Support Co. Ltd., Miyagi, Japan). The transmission output was up to 1W. Received Signal Strength Indicator (RSSI) was measured 500 times at 15 mm away from the surface of skin in the extension and 90° flexion of the knee (Fig1).

Introduction

Dislocation is one of severe complications after total hip arthroplasty (THA). Direct anterior approach (DAA) is useful for muscle preservation. Therefore, it might be also effective to reduce dislocation. The purpose of this study is to investigate the ratio and factors of dislocations after THA with DAA.

Materials & methods

Nine hundred fifity two primary THAs with DAA are examined. Mean age at operation was 64.9 yrs. 838 joints are in women and 114 (joints) in men. All THAs were performed under general anesthesia in supine position.

We reviewed the ratio, onset and frequency of dislocations, build of the patients, preoperative Japanese Orthopaedic Association (JOA) Hip scores, implant setting angles, pelvic tilt angles and diameter of inner heads.

Background

Hospital acquired MRSA is globally endemic and is a leading cause of surgical site infection (SSI). Of great concern is the emergence of community acquired MRSA (CA MRSA) with its unique virulence characteristics. Infected hip or knee prostheses due to MRSA are associated with multiple reoperations and prolonged hospital stay. Few studies have been done to assess for risk of SSI in MRSA carriers undergoing elective orthopaedic surgery following decolonisation. However in these studies, the eradication status was not confirmed prior to proceeding for surgical intervention.

Aim

The purpose of the study was to evaluate the incidence of SSI in MRSA carriers undergoing elective hip and knee arthroplasty, who had confirmed eradication of MRSA carrier status and to compare it with incidence of SSI in non MRSA carriers.

BACKGROUND

Periprosthetic infection is the most challenging complication following total knee arthroplasty (TKA). Poor oral hygiene has been assumed as an important risk factor for TKA infection. We aimed to investigate whether the improvement of oral hygiene through dental scaling could reduce the risk of TKA infection.

METHODS

A nested case control study was conducted and enrollees in the National Health Insurance Research Database (NHIRD) aged above 40 years who had received total knee arthroplasty (TKA) between 1999–2002 were included as the TKA cohort. The cases were patients who underwent resection arthroplasty for infected TKA, and each case was matched by 4 controls from the TKA cohort by gender, using incidence density sampling method. The frequency of dental scaling before the index date was analyzed and compared between the case and the control groups. Multiple conditional logistic regression was used to assess the frequency of dental scaling and the risk of TKA infection.

Introduction

Vitamin-E (VE, dl-α-tocopherol) is a powerful antioxidant for highly cross-linked polyethylene (XLPE). It was previously reported that VE-stabilized XLPE succeeded in retaining no measurable oxidation even after accelerated aging tests combined with cyclic loading or lipid absorption. Thus, VE-stabilized XLPE is nowadays recognized worldwide as one of the new standard materials in total hip arthroplasty (THA). However, the effects of such VE addition on physical behavior of polyethylene remain to be fully elucidated by contrast to the clear statement of its chemical role (i.e., the enhanced oxidation resistance) in the published literature. In this presentation, we shall attempt to provide those missing notations and to explore the microstructural and biomechanical role of VE in XLPE acetabular liner on the molecular scale.

Methods

The two different types of XLPE acetabular liners, VE-blended and VE-free (no VE-blended) component (n=3 for each sample), were investigated by means of laser-scanning confocal polarized micro-Raman spectroscopy. In both components, the cross-linking was achieved by electron-beam irradiation with a total dose of 300kGy in vacuum. Raman spectroscopy offers non-destructive, contactless, and high-resolution analyses of polymer morphologies. In this study, we performed an in-depth profiling of crystalline and non-crystalline phase (i.e., amorphous and intermediate phase between crystalline and amorphous regions) percentages and degree of molecular orientation in the above two liners before and after introducing the 10% plastic deformation via uniaxial compression loading at room temperature. These results were also compared to the morphological analyses under the same compression conditions performed on the virgin conventional polyethylene (Virgin liner) without radiation crosslinking as well as VE blending.

Objectives

Biologic agents (BIO) drastically changed the rheumatoid arthritis (RA) therapy from starting to use biologics at 2003 in Japan. The rate of orthopaedic surgery, especially total joint arthroplasty (TJA) may reflect trends in disease severity, management and health outcomes.

Methods

We surveyed the number and rate of orthopaedic surgeries and TJA in RA treatment with BIO in the last decade, so called BIO-era.

Purpose

Placement of the acetabular cup in accurate and optimal position is important in total hip arthroplasty (THA) to obtain satisfactory result. On the other hand, inaccurate manual cup placement with conventional cup placement guide was reported. We therefore have been applied the mechanical acetabular alignment guide for accurate cup placement. The purpose of this study was to validate the accuracy of the acetabular alignment guide for total hip arthroplasty.

Materials and methods

Between 2003 and 2014, 52 primary THAs were performed in 48 patients with using the acetabular alignment guide by one surgeon (HT). There were 42 female and 6 male with a mean age at operation of 71.1 years old (47 to 91). The original diagnosis were osteoarthritis in 43 patients (46 hips), and avascular necrosis of femoral head in 5 patients (6 hips). Used acetabular implants were Stryker® Trident AD HA cup in 24 hips and Wright medical® Acetabular Cup System in 28 hips.

After completion of anesthesia, half pins were inserted at the both anterior superior iliac spine vertically and the frame was attached to the pins horizontally in supine position. Then, the patients were placed in lateral decubitus position. Finally, the alignment rod, which indicated the optimal direction of the cup (abduction angle 40°, ante-version angle 20°), was connected to the frame. All operations were done by postero-lateral approach. Assessment of the cup abduction angle and ante-version angle was performed by Lewinnek's method using postoperative AP radiograph in supine position.

Purpose

The tibia first technique in unicompartmental knee arthroplasty (UKA) may have the advantage that surgeons can obtain a balanced flexion-extension gap. However, changes of the soft tissue tension during UKA has not been elucidated yet. The purpose of this study was to examine the correlation between the soft tissue tension before the femoral osteotomy and after the femoral component in place using the tensor in UKA.

Methods

Thirty UKAs for isolated medial compartmental osteoarthritis or idiopathic osteonecrosis were assessed. The mean age was 71.8±8.5 years old (range: 58–85), and the average coronal plane femorotibial angle (FTA) was 181.2±3.2 degree preoperatively. All the patients received a conventional medial Zimmer Unicompartmental High Flex Knee System (Zimmer Inc, Warsaw, Ind). The actual values of the proximal and posterior femoral osteotomy were calculated by adding the thickness of the bone saw blades to the thickness of the bony cut. Using a UKA tensor which designed to facilitate intra-operative soft tissue tension throughout the range of motion (ROM), the original gap before the femoral osteotomy, the component gap after the femoral osteotomy, and component placement were assessed under 20 lb distraction forces. (Figure 1)

Introduction

The low-contact stress (LCS) knee prosthesis is a mobile-bearing design with modifications to the tibial component that allow for meniscal-bearing (MB) or rotating-platform (RP). The MB design had nonconstrained anteroposterior and rotational movement, and the RP design has only nonconstrained rotational movement. The anterior soft tissues, including patellar tendon (PT), prevent anterior dislocation of the MB. The PT may consistently be exposed to overstressing. Therefore, we hypothesized that the PT thickness and width in MB prosthesis revealed more morphological changes than those of RP prosthesis due to degeneration of the PT induced by much mechanical stress of the MB movement. To confirm this hypothesis, we analyze the PT thickness and width induced by mobile-bearing inserts.

Objectives

Sixty LCS prostheses in 30 patients were analyzed. The average follow-up time was 61 months. MB prosthesis was used on one side of the knee and RP prosthesis was used on the contralateral side of the knee. All patients were chosen from group with no clinical complication, and all had achieved passive full extension and at least 90°of flexion. The average Hospital for Special Surgery Score was 94.6 ± 2.7.

Objective

The goal of total knee arthroplasty (TKA) is to achieve a stable and well-aligned tibiofemoral and patello-femoral (PF) joint, aiming at long-term clinical patient satisfaction. The surgical principles of both cruciate retaining (CR) and posterior stabilized (PS) TKA are accurate osteotomy and proper soft tissue balancing. We have developed an offset-type tensor, and measured intra-operative soft tissue balance under more physiological joint conditions with femoral component in place and reduced PF joint.

In this study, we measured intra-operative soft tissue balance and assessed the post-operative knee joint stability quantitatively at one month, six months and one year after surgery, and compared these parameters between CR and PS TKAs.

Material and Method

Sixty patients with varus osteoarthritis of the knee underwent TKAs (30 CR TKAs: CR and 30 PS TKAs: PS). Mean varus deformity in standing position was 11.1 degrees in CR, and 12.6 degrees in PS. All TKAs were performed by a single surgeon with measured resection technique. The external rotation of posterior femoral condyle osteotomy was performed according to surgical epicondylar axis in pre-operative CT. We measured intra-operative soft tissue balance using an offset-type tensor with 40 lbs of joint distraction force at 0, 10, 30, 45, 60, 90, 120 and 135 degrees of flexion. The joint component gap (mm) and varus angle (degrees) were measured at each flexion angles.

One month, six months and one year after surgery, we evaluated the knee stability at extension by varus and valgus stress radiography using Telos (10kg) and at flexion by epicondylar view with 1.5kg weight at the ankle. We measured joint separation distance at medial as medial joint looseness (MJL) and at lateral as lateral joint looseness (LJL). Intra-operative measurements and post-operative joint stabilities were compared between CR and PS using unpaired t-test. The change of joint looseness in each group was analyzed using repeated measures ANOVA.

Introduction

Planning of the stem antetorsion angle (SAA) is difficult with radiograph before THA. 3D THA planning software with CT is useful for planning the cup and the stem implantation angles before THA. However, even using the 3D planning software, we sometimes experience the different SAA during surgery compare to the planned SAA. The purpose of this study was to compare the implanted SAA with the preoperative planned SAA, which was planned by using 3D THA planning software.

Materials and Methods

CT evaluation was performed in 44 patients (5 males) who underwent primary THA. The mean age at surgery was 67 years (range 26–85 years). The mean BMI at surgery was 24.1kg/m² (15.6–31.7kg/m²). Forty-one patients had osteoarthrosis, 2 patients had osteonecrosis, and 1 patient had femoral neck fracture. All surgeries were performed in the supine position with the direct anterior approach. The OrthoPilot imageless navigation system (BBraun/Aesculap) was used during surgery. Excia stem was used in 34 patients and Bicontact stem was used in 10 patients. Planning of the surgery was performed using 3D THA planning software (ZedHip, Lexi). After surgery, SAA was measured with CT by the same 3D THA planning software. SAA was evaluated by comparison of the planned values before surgery with the CT measured values. Also, the shape of the femur and the stem were evaluated.

Background

Impaction bone grafting (IBG) using a circumferential metal mesh is one of the options that allow restoration of the femoral bone stock and stability of the implant in hip arthroplasty. Here we examined the clinical and radiographic outcome of this procedure with a cemented stem and analyzed experimentally the initial stability of mesh–grafted bone–cemented stem complexes.

Methods

We retrospectively reviewed 6 hips (6 patients) that had undergone femoral revisions with a circumferential metal mesh, impacted bone allografts, and a cemented stem. The mean follow-up period was 2.9 years (range, 1.4–3.8 years). Hip joint function was evaluated with the Japanese Orthopaedic Association hip score, and radiographic changes were determined from radiographs. The initial resistance of cemented stem complexes to axial and rotational force was measured in a composite bone model with various segmental losses of the proximal femur.

Introduction

Total knee arthroplasty is effective for the management of osteoarthritis of the knee. Conventional techniques utilizing manual instrumentation (MI) make use of intramedullary femoral guides and either extramedullary or intramedullary tibial guides. While MI techniques can achieve excellent results in the majority of patients, those with ipsilateral hardware, post-traumatic deformity or abnormal anatomy may be technically more challenging, resulting in poorer outcomes. Computer-assisted navigation (CAN) is an alternative that utilizes fixed trackers and anatomic registration points, foregoing the need for intramedullary guides. This technique has been shown to yield excellent results including superior alignment outcomes compared to MI with fewer outliers. However, studies report a high learning curve, increased expenses and increased operative times. As a result, few surgeons are trained and comfortable utilizing CAN. Patient-specific instrumentation is an alternative innovation for total knee arthroplasty. Custom guide blocks are fabricated based on a patient's unique anatomy, allowing for the benefits of CAN but without the increased operative times or the high learning curve. In this study we sought to evaluate the accuracy of PSI techniques in patients with previous ipsilateral hardware of the femur.

Methods

After reviewing our database of 300 PSI total knee arthroplasty patients, 16 were identified (10 male, 6 female) using the Zimmer NexGen Patient Specific Instrumentation System. Fourteen patients included in the study had a preexisting total hip arthroplasty on the ipsilateral side [Figure 1], 1 had a sliding hip screw, and 1 patient had a cephalomedullary nail. Postoperative mechanical axis alignment measurements were performed using plain long-standing radiographs [Figure 2]. The American Knee Society Score was used to evaluate clinical outcomes postoperatively.

Purpose

Femoral component malrotation is a common cause for persisting symptoms and revision following total knee arthroplasty (TKA). There is ongoing debate about the most appropriate use of femoral landmarks to determine rotation. The Sulcus Line (SL, See Figure 1) is a three-dimensional curve produced from multiple points along the trochlear groove. Whiteside's Line, also known as the anteroposterior axis (APA), is derived from single anterior and posterior points. The purposes of the three studies presented are to i) assess the SL in a large clinical series, ii) demonstrate the effect of parallax error on rotational landmarks, and iii) assess the accuracy of a device which transfers a geometrically corrected SL onto the distal cut surface of the femur.

Methods

The first study assessed the SL using a large, single surgeon series of consecutive patients (n=200) undergoing primary TKA. The postoperative CT scans of patients were examined to determine the final rotational alignment of the femoral component. In the second study measurements were taken in a series of 3DCT reconstructions of osteoarthritic knees (n=44) comparing the rotational landmarks measured along either the mechanical axis or the coronal axis of the trochlear groove. The third study assessed the accuracy of a novel trochlear alignment guide (TAG) using cadavers (n=10)

Purpose

The purpose of this study was to investigate the rate of return to work after total knee arthroplasty (TKA).

Materials and Methods

105 knees of 80 cases were tested after TKA surgery. 18 knees of 14 cases were men and 87 knees of 66 cases were women. The average age at the time of surgery was 71.5 years, and the average postoperative observation period was 25.5 months. All patients were with osteoarthritis of the knee. The use models were Hi-tech Knee II (Nakashima Medical, Okayama, Japan) CR type 99 knees and PS type 6 knees. The rate of return to work after surgery and employment rate of before and after surgery were examined for all cases. In addition,[1]age at surgery [2]ROM [3]JKOM score(Akai 2006) [4]Knee Society score (KSS Insall 1989) were examined in each case, and found the factors influenced on employment rate after TKA. The occupation was classified using major group of the International Standard Classification of Occupations (ISCO-08) defined by International Labour Organization (ILO) on 2007. Mann-Whitney U test was used for the statistical work.

Background

In total hip arthroplasty (THA), the importance of preserving muscle is widely recognized. It is important to preserve the short external rotator muscles because they contribute to joint stability and prevent postoperative dislocation. However, despite careful capsular release and femoral rasping, damage to the short external rotator muscles may occur. The Optymis Shot Stem preserves more bone and surrounding tissue than does a traditional primary stem. We investigated the usefulness of the stem in terms of the extent of preservation of the tendon attachment on the greater trochanter.

Method

In this study, we enrolled 31 consecutive patients (39 hips; 6 males, 25 females) who underwent THA. Simultaneous bilateral THA was performed in 8 patients. The patients’ mean age was 56.1 years. Diagnoses included developmental dysplasia in 35 hips (Crowe group 1: 31 hips, group 2: 4 hips), and sequel of Perthes disease in 4 hips. All THAs were performed via the direct anterior approach without traction tables. The femoral procedure was performed with the hip hyperextended, and posterior capsular release was performed if the femoral procedure became technically difficult. We compared the following among patients: the operative time, intraoperative blood loss, length of hospital stay, rate of posterior capsular release, postoperative radiographic findings, WOMAC score before and after surgery, and any complications.

Background

In total hip arthroplasty (THA), the importance of preserving muscles is widely recognized; therefore, muscle-sparing approaches are widely used. Recently, we reported that there are bony impressions, that we called the obturator attachment (OA), on the greater trochanter that indicate the insertions of the short external rotator tendons. In this study, we used a three-dimensional (3-D) template to evaluate damage to the insertions of the short external rotator muscles during a femoral procedure.

Methods

We investigated 12 hips in 10 patients who underwent THA. Preoperative CT imaging of the hip was performed, and 3-D reconstruction of the greater trochanter was used to visualize the bony impressions that indicate the insertions of the obturator internus and externus muscles (Fig 1A). We performed preoperative 3-D templating of two different femoral prosthesis (flat tapered-wedge stem: J-Taper, cylindrical straight stem: PerFix910) and then evaluated the extent of damage to the OA during the stem placement (Fig 1B, 1C). The extent of damage to the OA was classified using the following scale: grade 0, no damage of the insertion area; grade 1, less than 1/3; grade 2, equal to or more than 1/3–2/3; grade 3, equal to or more than 2/3; grade 4, complete.

INTRODUCTION

Venous thromboembolism (VTE), especially, deep vein thrombosis (DVT) in lower extremities, often seriously combined with pulmonary embolism (PE), is a major and critical complication after total hip arthroplasty (THA). For better disgonsis of VTEs, D-dimer test is one of the useful methods. The aim of this study was to evaluate the efficacy of D-dimer levels before THA.

MATERIALS AND METHODS

Medical records of patients with osteoarthritis who received THA between April 2009 and March 2010 were reviewed. Value of D-dimer at preoperative day 1, postoperative day 3 and 14 was examined in those patients. D-dimer levels were examined by Latex Immunity Nephelometry Measurement Method and the Kit (Sysmex Corporation, Kobe, Japan). A total of 327 patients with D-dimer values were examined. The values D-dimer of the available patients were under 1.0 μg/ml. Ninety-nine patients (30%) had a high D-dimer level. DVT was diagnosed by doppler ultrasonography at preoperative day 1, postoperative day 3 and 14. The sensitivity and specificity of D-dimer in different cutoffs were verified by Receiver Operating Characteristic (ROC) curve. The ROC curve was constructed to describe the relationship between the sensitivity and the false positive rate for different values of D-dimer to patients suspected of VTEs. The study protocol was approved by the institutional ethics committee.

Introduction

The deformity in osteoarthritis (OA) of the knee has been evaluated mainly in the frontal plane two dimensional X-ray using femorotibial angle. Although the presence of underlying rotational deformity in the varus knee and coexisting hip abnormality in the valgus knee have been suggested, three dimensional (3D) deformities in the varus and valgus knee were still unknown. We evaluated the 3D deformities of the varus and valgus knee using 3D bone models.

Methods

Preoperative computed tomography (CT) scans of twenty seven OA knees (fifteen varus and twelve valgus) undergoing total knee arthroplasty were assessed in this study. CT scans of each patient's femur and tibia, with a 2 mm interval, obtained before surgery. We created the 3D digital model of the femur and tibia using visualization and modeling software developed in our institution. The femoral coordinate system was calculated by the 3D mechanical axis and clinical transepicondylar axis and the tibial coordinate system was calculated by the 3D mechanical axis and Akagi's line. The 3D deformities of the knee were determined by the relative position of the femorotibial coordinate system, and described by the tibial position relative to the femur. The anteversion of the femoral neck were calculated to evaluate the relationship between the valgus knee and hip region.

Introduction

Post cam structure, which is the main structure of posterior-stabilized design (PS), is useful to realize the intrinsic stability of a knee prosthesis replaced for a case with the severe degeneration. A large size post might, however, shorten the range of knee motion. On the other hand, retrieval studies sometimes reveal the ultrahigh molecular weight polyethylene (UHMWPE) deformation or severe failure of the tibial post of PS knee. Strength of a tibial post of available design is obviously insufficient to prevent the severe deformation. Therefore, minimally required size of the post should be clarified for polyethylene inserts. In the present study, we performed finite element (FE) analysis assumed the mechanical conditions of a tibial post in a PS knee and aimed to design criterion of a post of polyethylene insert of a knee prosthesis.

Method

The shape of one commercially available knee prosthesis was referred as a posterior-stabilized knee prosthesis. The contour of the metallic femoral component was traced and digitized by hand. The contour of the UHMWPE insert was digitized by a micro computed tomography apparatus. Three dimensional finite elements were generated by a modeling software (Simpleware, Ltd. UK) as total 83000 four-noded tetrahedral elements. The bottom of the tibial insert was fully constrained. Load on femoral component was assumed to realize the tibial post impingement under several kinds of knee motions. Posterior load 100 N or 500N at the 10 degree hyperextension, anterior load 500N or 1000N during 120 degree flexion were applied (Fig. 1). The software of FE analysis was LS-DYNA ver.971 (Livemore Software Technology Corp. USA). The hardware was Endeaver Pro-4500 (EPSON Corp. Japan). The distributed values of von Mises stress and plastic strain of the tibial post were shown as the results of the analysis.

Background

Most of contemporary total knee systems address on improving of range of motion and bearing materials. Although new total knee designs in most systems accommodated the knee morphology according to gender differences, reestablishing of the same anterior offset of the distal femur during total knee arthroplasty (TKA) has not been well addressed. Furthermore, in most total knee systems, the anterior offset of the femoral component is constant regardless of the increment of the femoral size. We hypothesized that change of the anterior offset of the distal femur during TKA might affect the quadriceps strength and immediate clinical outcomes which may result in improved design of the future femoral component.

Purpose

To evaluate the peak quadriceps strength and immediate clinical outcomes related to the change of anterior offset of the distal femur during TKA.

Background

Soft tissue tension and intra-articular pressure distribution plays a crucial role in postoperative function and survivorship of TKA prosthesis. Although posterior stabilized (PS) and cruciate retaining (CR) knees have both been successful in relieving pain and restore function, it is reported that the joint gaps were significantly distinct between the two designs during flexion. The aim of this study is to find out what is the difference in intra-articular pressure distribution between PS and CR knees.

Methods

We prospectively included 45 consecutive patients (50 knees) scheduled for total knee arthroplasty between August, 2013 and April, 2014 in our hospital. 23 patients (25 osteoarthritic knees) received a Genesis II CR TKA (Smith & Nephew, Memphis, USA), and the other 22 patients (25 osteoarthritic knees) received Genesis II PS TKA (Smith & Nephew, Memphis, USA). During operation, after the bone osteotomy and soft tissue balance were completed, we measured and compared the intra-articular pressure distribution at 0°, 30°, 45°, 60°, 90°, and 120° flexion with a previously validated “Wireless Force Measurement System (WFMS)”. Joint gaps were measured at extension and 90° flexion. The soft tissue was not considered balanced until the medial and lateral joint gap difference ≤ 2mm at extension and 90° flexion. There are no significant differences in age, gender, BMI, varus angle and flexion deformity, and preoperative range of motion between the two groups. The medial-lateral pressure distribution and total pressure were compared at different angles between CR and PS knees.

Introduction

Patient satisfaction after total hip arthroplasty (THA) has been reported to be significantly better than after total knee arthroplasty (TKA). The same has been observed for the capacity to forget during daily life activities about the operated joint. Recently a new patient reported outcome score, the Forgotten Joint Score (FJS-12) a twelve item questionaire, has been used to evaluate postoperative outcome in joint arthroplasty. A better FJS-12 score was measured in THA than in TKA objectivating the intuitive feeling that the joint was more forgotten in THA than in TKA.

Hypothesis

A higher preoperative FJS-12 score is the reason for a higher postoperative FJS-12 score in THA compared to TKA

Introduction

Patellofemoral arthroplasty (PFA) can give excellent results in well-selected patients. Axial alignment has been extensively studied in this type of surgery. However because there is no distal femoral cut, coronal alignment in PFA is less well known. The position of the patellofemoral component decides the varus or valgus alignment of the implant.

Hypothesis

Coronal alignment in PFA (PFJ-Gender, Zimmer, Warsaw, US) is determined by the anterior condylar anatomy and features an important variance influencing coronal alignment.

Introduction

Knee osteoarthritis is a leading cause of disability around the world. Traditionally, total knee arthroplasty (TKA) is the gold standard treatment; however, unicompartmental knee arthroplasty (UKA) has emerged as a less-invasive alternative to TKA. Patients with UKAs participate earlier with physical therapy (PT), have decreased complications, and faster discharges (1, 2). As UKA has evolved, so has computer navigation and robotic technology. The Robotic Assisted UKA combines the less invasive approach of the UKA with accurate and reproducible alignment offered by a robotic interface (3)(Figure1).

A key part of a patient's satisfaction is perioperative pain control. Femoral nerve blocks (FNB) are commonly performed to provide analgesia, though they cause quadriceps weakness which limits PT (4). An alternative is the adductor canal block (ACB) which provides analgesia while limiting quadriceps weakness (4). The adductor canal is an aponeurotic structure in the middle third of the thigh containing the femoral artery and vein, and several nerves innervating the knee joint including the saphenous nerve, nerve to the vastus medialis, medial femoral cutaneous nerve, posterior branch and occasionally the anterior branch of the obturator nerve (5).

In a multi-modal approach with Orthopedic Surgery, Regional Anesthesia, and PT departments, an early goal directed plan of care was developed to study ACB in UKA with a focus on analgesia effectiveness and PT compliance rates.

Methods

Following IRB approval, we performed a case series including 29 patients who received a single shot ACB.

Primary outcomes were distance walked with PT on postoperative day (POD) 0 and 1 and discharge day. Our secondary outcomes included Visual Analog Scale (VAS) scores in the post-anesthesia care unit (PACU), 8 and 24 hours postoperatively and oral morphine equivalents required for breakthrough pain.

Aims

This retrospective study aimed to determine the causes of in-hospital death after Neck of Femur (NOF) fracture in Southampton General Hospital (SGH) over a 6 year period, comparing the clinical cause of death with findings at post-mortem. A previous study showed discrepancies between pre-mortem clinical diagnosis and autopsy findings after in-hospital deaths in SGH.

Methods

The study included all patients who died in SGH after NOF fracture from 2007–2013. Case notes were reviewed to determine the pre-mortem clinical diagnosis and compared with the autopsy findings to analyse major and minor discrepancies. Data were also analysed from the period 1997–2003 in order to compare the causes of death.

Introduction

Impaction bone grafting for reconstitution of acetabular bone stock in revision hip surgery has been used for nearly 30 years. We report results in a group of patients upon whom data has been collected prospectively with a minimum ten year follow-up.

Material and Methods

Acetabular impaction grafting was performed in 305 hips in 293 patients revised for aseptic loosening between 1995 and 2001. In this series 33% of cases required stainless steel meshes to reconstruct medial wall or rim defects prior to graft impaction. These meshes were the the only implants used for this purpose in this series. All Paprosky grades of defect were included. Clinical and radiographic outcomes were collected in surviving patients at a minimum of 10 years following the index operation; mean follow-up was 12.4 years (SD 1.5; range 10.0–16.0).

Introduction

Recently, there are increasing literatures of the in vivo kinematics of total knee arthroplasty (TKA). Those previous studies have been reported in regard of either intra-operative kinematics or post-operative kinematics. However, the direct correlation between intra- and post-operative kinematics of TKA has not been revealed. There are no evidences that intra-operative kinematics can lead to post-operative kinematics.

Purpose

The purpose of this study is to verify the direct correlation between intra- and post-operative kinematics of TKA.

Objectives

Our principle is to bring the socket back to the true acetabulum position. A large structural bone graft is required for severe subluxation. We obtained good long-term results with structural bone grafts. It is necessary to evaluate the bone graft 3 dimensionally, not 2 dimensionally.

M and M

We evaluated our 305 primary THAs operated from April 2010 to Mar 2014. Structural bone grafts were utilized on the acetabulum in 39 cases (12.8%).

We measured the CE angle on post-operative plain coronal x-rays. 3D-CT evaluation was carried out on the cases with CE angles of 0 degrees or less.

We checked the position of the graft and see how much surface area the graft occupies of the total area that receives the load.

Hypothesis

The use of cartilage compensated virtual standing CT images for pre surgical planning improves the reliability of preoperative planning.

Materials and Method

Sampling included in this study were > 62 years of age (mean age 58.17 yrs ±3.54 yrs, range 55–62) with symptomatic isolated medial osteoarthritis, genu varum (mean varus 5.6°±2.6 °, range 2.1°–8.6°), good range of motion (flexion > 90° and flexion contracture < 10°) and with minimal ligamentous instability. All subjects had obtained a pre-op CT scan, MRI scan and weight-bearing long bone x ray. Post-op CT and long standing x-rays were taken prior to hospital discharge.

A virtual software suite (HTO-OP3D, Zapalign Inc, Seoul, Korea) was utilised to determine an optimal osteotomy site, hinge location and a gap necessary to achieve the targeted virtual passing point.

Prerequisite to performing the necessary calculations a virtual standing pose for each patient specific bone models was created using the following steps.

To transfer the pre surgical plan intra-operatively, a customised alignment jig was manufactured

Objection

Multimodal local periarticular injection can be effective for pain management after total knee arthroplasty. We have investigated to get the similar results after total hip arthropasty.

Methods

Sixty patients undergoing total hip arthroplasy were divided to two groups. One were with multimodal local periarticular injection(Group M) and the other were with single intraarticular injection Group C, conventional method. We injected a “cocktail” agents into the soft tissue (capsule, synovium, muscle, subcutaneous fat tissue, skin) around the implants. Those were contained Morphinesulfate, Ropivacaine, Adrenaline, Methylpredonisolone, Ketoprofen, and Normal saline. We compared the VAS(at rest and during walking), the duration of the mobilization and active SLR, and any complicaions.

Introduction

It is important to measure 2-dimensional (2D) polyethylene wear in total hip arthroplasty (THA) accurately in order to estimate value of wear performance. However, wear vector direction is usually defined in a coordinate system specific manner, which sometimes leads to confusion and makes it difficult to compare measures between techniques. We systematically evaluated the influence of four different coordinate system definitions for the measurement of 2D wear in acetabular cups form radiographs.

Materials and Methods

We performed 2D wear measurement of 152 hips that underwent THA using a 26mm CoCr femoral head with the same design of cementless acetabular shell between September 2003 and March 2005. All hips received either a CPE liner (76 hips, gamma sterilized at 25 kGy) or a XLPE liner (76hips, 10Mrad e-beam irradiation, EtO sterilized) randomly during the surgery. The average follow-up was 81.6±8.2 months.

Supine AP radiographs obtained postoperatively at 6 months and final follow-up were assessed for each femoral head penetration and angle using Roman v1.70 software (http://www.cookedbits.co.uk/roman/). The wear magnitude and angle between the two follow-ups was calculated using four coordinate system definitions:

#1; the line tangent to both ischiums was defined as 0 degrees, with wear directed medially defined as positive and wear detected laterally defined as negative. (Martell; JBJS Vol79-A No11 p1635–41)

INTRODUCTION

The concept of anatomical stam is fit-and-fill in the proximity of the femur and to expect wall fixation, following to reduce thigh pain and stress shielding. Although the femoral medullary form and size are different in each races. CentPillar TMZF stem (stryker ^®) is anatomical stem designed based on computer-tomography of Japanese femurs. The purpose of this study was to evaluate clinical and radiographic outcomes of CentPillar TMZF stem at a mean of 3.6 years postoperatively.

METHODS

We asseses the results of 98 primary total hip arthroplasty (THA) performed using a CentPillar TMZF stem in 91 Japanese patients (4 males, 94 females) undergoing surgery between August 2007 and June 2011, the mean age at the time of surgery was 62.0 (41–81) years old. The Diagnosis were osteoarthritis (OA) in 91 hips, rapidly destructive coxopathy (RDC) in 4 hips, rheumatoid arthritis (RA) in 3 hips. Clinical and radiographic assessments were performed for every patient for every follow up using Japan Orthopaedic Association (JOA) Score, thigh pain, revision surgery and complications. Radiographic assessments were including stem alignment on anteroposterior radiograph, stress shielding, bone remodeling, radiolucent line, osteolysis, loosening and subsidence.

Background

Evidence from recent trials has supported the efficacy of periarticular analgesic injection for pain control following total knee arthroplasty (TKA). However, no randomized controlled trial has compared the efficacy of periarticular analgesic injection with that of other regimens for simultaneous bilateral TKA.

Methods

We conducted a randomized controlled trial in which patients scheduled for simultaneous bilateral TKA were randomly assigned to receive periarticular analgesic injection or epidural analgesia. In the periarticular analgesic injection group, the injection contained 7.5 mg/ml ropivacaine 40 ml, 10 mg/ml morphine hydrochloride hydrate 1.0 ml, 1.0 mg/ml epinephrine 0.6 ml, methylprednisolone 80 mg, and ketoprofen 50 mg. These agents were mixed with normal saline to a combined volume of 120 ml. The 60 ml of the cocktail was injected into each knee. In the epidural analgesia group, the catheter was placed at the L2–3 or L3–4 level, and connected to an infusion pump delivering continuous infusion (flow rate: 4 ml/h) of 100 ml of 2 mg/ml ropivacaine plus 1.0 ml of 10 mg/ml morphine hydrochloride hydrate. Surgery was managed under spinal anaesthesia. Surgical techniques and postoperative medication protocols were identical in both groups. The primary endpoint was postoperative pain at rest, quantified as the area under the curve (AUC) of the score on a visual analogue scale.

Background

A first generation once annealed highly crosslinked polyethylene (HXLPE) was introduced in 1998. At 8 years it was reported to have a 78% reduction in wear compared with conventional polyethylene and no osteolysis. However, concerns regarding the long-term performance and oxidative resistance of this annealed material exist because of the presence of free radicals.

Questions/purposes

We therefore addressed the following questions: (1) Does the improvement in wear observed at earlier follow-up continue out to 15 years? (2) What is the incidence of osteolysis in this group of patients?

Introduction

Technological advances in the processing of polyethylene have led to improved survivorship of total hip arthroplasty. The purpose of this study was to determine if a second generation highly cross-linked polyethylene could improve upon wear rates compared to conventional and first generation cross-linked polyethylene in patients undergoing primary total hip arthroplasty.

Methods

Linear and volumetric wear rates of a second generation highly cross-linked polyethylene were evaluated following primary total hip arthroplasty. There were 44 patients with an average age of 68.6 years and mean follow-up of 5.3 years. Patients were evaluated at six weeks, one, two and five years. Wear rates were determined from digitized AP Pelvis radiograph by an independent observer using Martell's software. Acetabular inclination and femoral head size were also evaluated to determine variability in wear rates.

INTRODUCTION

Osteochondral lesions of the knee are relatively common both in young and senior population. The very disabling clinical symptoms, in association to the scarce regenerative capacity of the articular cartilage and the increased risk of developing a secondary osteoarthritis make an effective treatment mandatory.

MATERIALS AND METHODS

From December 2008 to January 2013, 34 patients (35 knees), 24 males and 10 females (mean age 36.2 years range 14–66) underwent implant of Maioregen® (Finceramica Faenza S.P.A, Italy) biomimetic osteochondral scaffold. In 17 cases the osteochondral lesion was cause by an osteochondritis dissecans (acute or sequela), in 13 cases by a spontaneous osteonecrosis and in 4 cases the etiology was traumatic. Patients were evaluated with subjective IKDC and Tegner Lysholm scores, VAS and Tegner Activity Scale before surgery and at regular follow up (mean follow up 38.4 months, range 13 months max 63 months).

Introduction

Support cages are often used for reconstruction of acetabular bone defects in revision total hip arthroplasty. A Burch-Schneider cage is one of the most reliable systems that has shown good clinical results. It has an ischial flange and an iliac plate for screw fixation to the ilium. It is sometimes necessary to bend the flange or the plate to fit the shape of the peri-acetabulum. However, the frequency, indications, and characteristics of bending the flange or plate have not been reported. To clarify them, a simulation study was conducted.

Materials and methods

Twenty-five cases with acetabular bone defects of Paprosky type 2, 3, or 4 were the subjects of this study. A 3D template surgical simulation was conducted using 3D surface models of the Burch-Schneider cage and acetabulum. The size of the cage was determined by the size of the cavitary bone defect. Placement of the cage was performed in two ways. One was the iliac plate fitting method, in which fitting of the iliac plate to the ilium was performed first, followed by bending of the ischial flange to keep the flange in the center of the ischium. When bending of the flange was needed, it was bent at the base. The other method was the ischial flange fitting method, in which the ischial flange was inserted from the center of the ischium, followed by bending of the iliac flange to adapt to the ilium. When bending of the plate was needed, it was bent at the base. In both methods, the direction and angle of bending were measured.

Introduction

It is essential to investigate the tribological maturation of tissue-engineered cartilage that is to be used in medical applications. The frictional performances of tissue engineered cartilage have been measured using flat counter surfaces such as stainless steel, glass or ceramics. However, the measured friction performances were significantly inferior to those of natural cartilage, likely because of cartilage adhesion to the counter surface. Tamura et al. reported that a poly (2- methacryloyloxyethyl phosphoryl-choline (MPC)) grafted surface shows low friction coefficient against cartilage without the adhesion to be equivalent to those for natural cartilage-on-cartilage friction. [1]

On the other hand, Yamamoto et al. reported that applying a relative sliding movement had a potential to alter the expression of tribological function of regenerated cartilage of chondrocytes. [2] In this paper, the effects of the relative sliding movement on the expression of bone marrow stromal cells (BMSC)s were investigated using the poly(MPC) grafted surface as a counter surface.

Material and methods

BMSCs seeded onto fibroin sponge scaffolds were cultured by using the stirring chamber system (Figure 1), which can apply a relative tribological movement to the surface of the specimens. Three culture conditions were applied (dynamic in stirring chamber as frequency as 40 min [D1], as 40 sec [D2] and static in stirring chamber group [S]). The specimens were set into stirrer on a poly(MPC) grafted surface (MPC polymer coated surface, SANSYO).

As a counter surface in friction tests, the poly(MPC) grafted surface was prepared by atom transfer radical polymerization, and the regenerated cartilage was prepared by seeding 5×10⁵ cells (BMSCs from rat bone marrow) onto fibroin sponge scaffolds (8 mm diameter and 1 mm thickness) and by 14 days culture.

Introduction

Dl-α-Tocopherol (VE)-blended non-crosslinked UHMWPE has been developed as a bearing surface material for knee prostheses due to the radical scavenging capabilities of vitamin E and has demonstrated a low wear rate in knee simulator testing [1,2]. In previous our study, VE-blended, crosslinked UHMWPE has demonstrated a low wear rate in hip simulator testing [3, 4]. As the radical scavenging capabilities also reduce the crosslinking degree of the material, multiple dose crosslinking has been investigated. However, these crosslinked UHMWPE materials may have different mechanical properties, as each crosslinking process, especially the annealing condition, is different. Additionally, there is little information about VE-blended, crosslinked UHMWPE with different annealing conditions. In this study, the effect of annealing temperature was investigated with regard to tensile strength, crosslink density, and crystallinity of VE blended, crosslinked UHMWPE.

Method

VE blended samples were manufactured via direct compression molding following the blending of UHMWPE resin powder (GUR1050, Ticona Inc.) with VE (dl-α-tocopherol, Eisai Co. Ltd.) at 0.3wt%. The virgin samples were derived similarly, but without the addition of VE. Both materials underwent crosslinking by irradiation via a 10MeV electron beam at 300kGy and were then heat treated at several temperatures (25, 80, 110, 130 and 150 °C) for 24 hours.

Gel content, which can be interpreted as cross-link density, was determined by measuring the weight of the samples before and after soaking in decahydronaphthalene at 150 °C for twelve days.

Tensile tests were carried out following JIS K 7113, with the cross head speed set at 50 mm/min.

Crystallinity was determined by using DSC and integrating over the enthalpy curve from 80 to 150 °C and normalizing with the enthalpy of melting for 100% crystalline polyethylene.

Introduction

Snapping scapula symptoms occur due to disruption of the smooth gliding motion between scapula and thoracic cage. Patients present with pain in the scapulothoracic area aggravated by overhead and repetitive shoulder movements. It is often associated with audible and palpable crepitus, clicking, crunching, grating or snapping sensation. Open or arthroscopic scapulothoracic surgical treatment is an option when non-operative treatment modalities fail. The aim of our study was to assess the outcome of scapulothoracic arthroscopic treatment in patients with painful snapping scapula.

Methods

Eight patients underwent scapulothoracic arthroscopic treatment for painful snapping scapula. Pre-operatively, all these patients had a trial of conservative treatment modalities for at least 6 months, consisting of activity modification, analgesia and physiotherapy for restoration of normal scapulothoracic kinematics. All patients had a temporary pain relief following a local anaesthetic and steroid injection.

We graded the crepitus from 0 to 3 - 0 being no crepitus, 1 being palpable but not audible crepitus, 2 being soft audible crepitus and 3 being loud crepitus.

Operations were performed with the patients in either prone or semi-prone position. The arm was placed in the “chicken wing” position (arm in full internal rotation with the hand placed on the back), so that the scapula lifted up from the chest wall. Two portals along the medial border of scapula were used for arthroscopy and instrumentation. In two cases a superior portal was also used.

Outcome was assessed by pre and postoperative visual analogue score (VAS) and Oxford Shoulder Score. Pre and postoperative scores were compared using paired t-test. The significance level was set at P <. 05.

Background

The use of Computed Tomography (CT) as a medical imaging tool has widespread applications in the field of knee surgery. Surgeons use a CT scan in a conventional way during the pre-operative stage, to plan the position of the femoral component in the horizontal plane. In the post-operative stage, the use of a CT scan is a routine tool in the evaluation of failed TKA as rotational malalignment of the femoral component has been determined as a cause of poor clinical outcome after TKA.

Aim

How accurately can we measure the different angles with importance for alignment on a 3D-image in comparison to a standard CT, 2D, image.

Introduction

Total Knee Arthroplasty (TKA) is a proven successful and cost-effective method to relieve pain and improve joint function and quality of life in patients with advanced knee arthritis. However, after a TKA, only 75 to 89% of patients are satisfied. Since patient satisfaction is one of the main objectives of elective orthopaedic surgery, it is important to investigate the reasons for dissatisfaction and develop remedial strategies.

Objectives

The aims of the current project are to investigate patient satisfaction after TKA and establish physical, mental and social determinants of patient satisfaction and overall socio-economic costs associated with unsatisfactory outcome. The global objective is to identify patients most likely to benefit from primary TKA, establish optimal evidence-based indications and timing for TKA, and address the necessity to educate patients preoperatively towards realistic expectations or propose alternative therapies. Based on the results, a composite score for patient selection will be developed using objective and subjective parameters. Cut-off values for acceptable indications for TKA will be proposed.

INTRODUCTION

Systemic levels of metal ions are surrogate markers of in-vivo wear of metal-on-metal hip resurfacings (MoMHRA). The wear-related generation of metal ions is associated with component size and positioning but also with design specific features such as coverage angle, clearance, metallurgy and surface technology.

OBJECTIVES

The objective of the study was to investigate whether a hip resurfacing design (ACCIS) with TiNb engineered bearing surfaces would generate less chromium (Cr) and cobalt (Co) ions during and after the run-in phase of wear and whether Ti ions could be detected indicating wear of the coating.

INTRODUCTION

Meniscal tears are very common and treated surgically by suturing or partial or total meniscectomy. After meniscectomy, the tibiofemoral contact area is decreased whih leads to higher contact stresses associated with clinical symproms and a faster progression of tibiofemoral osteoarthritis. Besides meniscus allograft transplantation, artificial implants have been developed to replace the menisci after meniscectomy.

AIM

We investigated the short- and medium-term clinical results and survivorship of two artificial meniscus implants used as a treatment for post-meniscectomy pain in young to middle-aged patients: the anchored polyurethane degradable Actifit® (2007–2013) and the non-anchored polycarbonate-urethane NUSurface® meniscal implants (2011–2013).

Summary

The effect of polyethylene wear and lift-off between the tibial and femoral components on the mechanical axis was assessed in primary TKA (Total Knee Arthroplasty) based on retrieval data and full leg radiographs.

Introduction

Controversy exist regarding performing a TKA with component placement in physiologic versus neutral alignment. Some literature indicates good survivorship and superior clinical outcome in undercorrected TKA's for varus osteoarthritic knees. However, other literature indicates decreased survivorship and coronal plane alignment is still one of the contributing factors to wear in total knee arthroplasty (TKA). The two determinants of the intra-articular deformity in TKA arepolyethylene wear and lift-off between the tibial and femoral compartment. The goal of this study was to evaluate the impact of wear and lift-off on the mechanical axis in neutral and varus aligned TKA's.

Introduction

Coronal plane alignment is one of the contributing factors to polyethylene wear in total knee arthroplasty (TKA). The goal of this study was to evaluate the wear and damage patterns of retrieved tibial polyethylene inserts in relationship to the overall mechanical alignment and to the position of the tibial component.

Materials and methods

Based on full-length radiographs, ninety-five polyethylene inserts retrieved from primary TKA's with a minimum time in-vivo of five years were analysed for wear and damage. Four alignment groups were compared: valgus, neutral, mild varus and moderate varus. Varus and valgus positioning of the tibial component was analysed for damage score for the neutral and varus aligned groups.

Introduction

Fast track arthroplasty regimens require preservation of motor power to perform early rehabilitation and ensure early discharge (1). Commonly performed nerve blocks like femoral and Sciatic nerve blocks results in motor weakness thereby interfering with early rehabilitation and may also predispose to patient falls (2, 3). Hence, targeting the terminal branches of the femoral and sciatic nerves around the knee joint under ultrasound is an attractive strategy. The nerve supply of interest for knee analgesia are the terminal branches of the femoral nerve, the genicular branches of the lateral cutaneous nerve of thigh, obturator and sciatic nerves (4).

Methods

We modified the performance of the adductor canal block and combined it with US guided posterior pericapsular injection and lateral femoral cutaneous nerve block to provide analgesia around the knee joint. The femoral artery is first traced under the sartorius muscle until the origin of descending geniculate artery and the block is performed proximal to its origin. A needle is inserted in-plane between the Sartorius and rectus femoris above the fascia lata and 5 ml of 0.5% ropivacaine (LA) is injected to block the intermediate cutaneous nerve of thigh. The needle is then redirected to enter the fascia of Sartorius to deliver an additional 5ml of LA to cover the medial cutaneous nerve of thigh following which it is further advanced till the needle tip is seen to lie adjacent to the femoral artery under the Sartorius to perform the adductor canal block with an additional 15–20 ml of LA to cover nerve to vastus medialis, saphenous nerve and posterior division of the obturator nerve (Fig 1). The lateral cutaneous nerve of thigh is optionally blocked with 10 ml of LA near the anterior superior iliac spine between the origin of Sartorius and tensor fascia lata (Fig 2). The terminal branches of sciatic nerve to the knee joint is blocked by depositing 25 ml of local anesthetic solution between the popliteal artery and femur bone at the level of femoral epicondyles (Fig 3).

INTRODUCTION

The burden of Musculoskeletal (M-S) diseases and prosthetic revision operations is huge and increasing rapidly with the aging population. For patients that require a major surgical intervention, procedures are unsafe, uncertain in outcome and have a high complication rate. The goal of this project is to create an ICT-based patient-specific surgical navigation system that helps the surgeon safely reaching the optimal functional result for the patient and is a user friendly training facility for the surgeons. The purpose of this paper is to demonstrate the advancements in personalized musculoskeletal modeling for patients who require severe reconstructive surgery of the lower extremity.

METHODS

TLEMsafe is a European Project dedicated to generating semi-automated 3-D image-analyzing tools to simulate the musculoskeletal (M-S) system. The patient-specific parameters are fed into models with which the patient specific functional outcome can be predicted. Hence, we can analyze the functional effect e.g. due to placement of prosthetic components in a patient. Surgeons can virtually operate on the patient-specific model after which the model predicts the functional effects. Once the optimal plan is selected, this is fed into a computer navigation system (see figure 1).

Introduction

The initial stress distribution in the femur after total hip arthroplasty (THA) influences the remodeling of the bone and the clinical results. We conducted thermoelastic stress analysis to evaluate the surface stress distribution in femurs after THA in vitro and elucidated the changes in the stress distribution that were due to the stem design. Using this method, we can analyze the change in the sum of the principal stresses on the basis of the changes in temperature at the bone surface and visualize the change three-dimensionally.

Objectives

We compared the thermoelastic stress analysis results with the clinical results of specially shaped stems that have two flanges, one anterior and one posterior.

Introduction

The aim of this study is to verify the intra-rater and inter-rater reliability of intra-operative kinematics by hand in TKA using a computer assisted image-free navigation system.

Material and Methods

Total knee arthroplasty (TKA) was performed on the knees of twelve (12) patients with knee navigation by one surgeon. Patients were divided into two groups: Group A included six knees that were operated on with assistant A (senior joint surgeon); and Group B included the other six knees that were operated on with assistant B (resident). For each knee, axial rotation was evaluated three times by the operator and the assistant using a navigation system at 30°, 60°, 90°, 120° passive flexions by hand. Intra-class correlation coefficients (ICC) were calculated for each evaluation to examine intra-rater and inter-rater reliability.

Introduction

Periprosthetic joint infection (PJI) is a significant challenge to the orthopedic surgeon, patient, hospital, and insurance provider. As the number of total hip and knee replacements has increased, the number of revision procedures has also increased. Revisions for infection require a greater amount of hospital and surgeon resources than noninfectious revisions. Our study compares the financial information for all two-stage revision surgeries performed at our tertiary referral center for hip or knee PJI over the last four years, separating them into two groups: referral versus self-originating cases.

Methods

We performed a review of all patients who underwent two-stage revision hip or knee arthroplasty for infection between 2008 and 2013 at our facility. We collected detailed financial information for patients and separated them into referral versus self-originating cases, indicating whether index surgery was performed at an outside facility or at our facility, respectively. Only those patients who underwent full two-stage procedure at our facility were included.

Introduction

This study reports outcomes of primary and revision total hip arthroplasties of a recalled metal-on-metal (MOM) monoblock prosthesis performed by a single surgeon.

Methods

We performed a retrospective review of all patients who underwent both primary and revision total hip arthroplasties at our institution between 2006 and 2014. Only those patients who underwent primary recalled MOM monoblock prosthesis placement and/or revision of the recalled prosthesis were included. We evaluated revision group versus non-revision group for age, BMI, gender, existence of medical comorbidities, primary cup abduction and anteversion, primary combined angle, post-operative complications, cobalt and chromium ion levels, and Harris Hip Scores. Student t-test was used to compare groups.

Introduction

Biological fixation through bone ingrowth and ongrowth to implants can be achieved with a variety of surface treatments and technologies. This study evaluated the effect of two different three dimensional surface coatings for CoCr where porosity was controlled through the use of different geometry of CoCr beads in the sintering process.

Methods

Test specimens in Group A were coated with conventional spherical porous-bead technology. The porous coating technology used on Group B was a variation of the conventional porous-bead technology. Instead of spherical beads, cobalt-chromium particles in irregular shapes were sieved for a particular size range, and were sintered onto the specimen substrate using similar process as Group A. The geometry and the size variation of the particles resulted in a unique 3D porous structure with widely interconnected pores.

Three implants were placed bicortically in the tibia. Two implants were placed in the cancellous bone of the medial distal femur and proximal tibia bilaterally with 4 implantation conditions (2 mm gap, 1 mm gap line-to-line, and press fit). Animals were euthanized at 4 or 12 weeks for standard mechanical, histological and histomorphometric endpoints.

Purpose

The aim of this study is to describe the influence of sitting and standing posture on sagittal pelvic inclination in preoperative total hip replacement patients to assist with correct acetabular component positioning.

Methods

Lateral radiographs of the pelvis and lumbar spine in sitting and standing of preoperative hip arthroplasty patients with primary hip osteoarthritis were extracted. Pelvic tilt was measured using the vertical inclination of a line from the ASIS to pubic tubercle. Sacral inclination was measured as the angle between the anterior surface of the sacrum and a horizontal reference. Figure one is a representation of the pelvic tilt angle and sacrel inclination angle taken during standing. The Cobb angle of the lumbar spine was recorded represented for a sitting patient in figure 2. Hip flexion was recorded (figure 2).

Introduction and Aims

The 21^st Century has seen ceramic bearings become an increasingly popular choice in total hip arthroplasty due to their high wear resistance and inert wear debris without osteolysis promising a long term bearing solution. Early ceramic bearings were hindered by fracture but improved manufacturing processes and materials subsequently produced stronger ceramics. These third generation ceramics showed greatly reduced fracture rates but there is limited evidence in the literature reporting their long term survival and wear characteristics. The purpose of this study was to determine osteolysis and survival rates of Alumina ceramic bearings in cementless total hip arthroplasties with a minimum follow-up of 15 years.

Methods

We analyzed a series of 301 third-generation alumina-on-alumina cementless primary total hip replacements in 283 patients. The average age of the patients at the time of the arthroplasty was fifty-eight years, 51% were in women and 54% were right sided. All procedures were performed using the same surgical technique and the same implant at a single centre. Patients were followed up at six weeks, one, two, five, ten and 15 years. At 15 years postoperatively 46 patients (17%) had died of unrelated causes and 31 (10.2%) were lost to follow-up. Patients were assessed clinically and radiographically. Retrieved bearings were analyzed for wear.

Background

Total Hip Arthroplasty (THA) using the Direct Anterior Approach (DAA) is a muscle sparing approach which promotes early mobilisation of patients. It is a technically challenging approach shown to have a high rate of complications, especially during the learning curve. Here we present the results of 157 cases of THA via a DAA on a standard theatre table, with a minimum of 6 months follow-up.

Materials & Methods

The authors conducted a prospective study on a group of 149 consecutive patients undergoing 157 cementless primary THAs for coxarthrosis, 8 bilateral. The same surgical technique was used in all patients, performed by the senior author WLW at a single centre. The average age of the patients at time of surgery was 69 years, 78% were female and 57% were right sided. All implants were uncemented, with bearings being ceramic on ceramic or Ceramic on highly cross-linked polyethylene. Patients were assessed clinically and radiographically pre- and post-operatively at 6 weeks, 6 months, 1 and 2 years. Intra-operatively, navigation was used to guide cup position and assess offset and leg length.

Objective

Recently, the short stem, taken on preservation of the femoral bone, is available on total hip arthroplasty and on femoral head prosthetic replacement. The handling of the short stem is easier than that of standard stem on implantation of femur. However, it would be difficult to make the direction of stem axis straight in femoral marrow cavity. Actually we experienced that the lateral cortical bone of the proximal femur was ground unevenly on rasping for implantation of the short stem. The aim of this study was to identify the efficacy of dulled rasp on implanting the short stem.

Subjects and Methods

We examined 42 hips of 39 patients who underwent the primary total hip arthroplasties with short stems in our institution from August 2011 to April 2014. Primary diseases were 28 osteoarthritides, 6 idiopathic osteonecrosises of the femoral heads and 5 others. We categorized N group as using standard rasp with sharpened blades and M group as using modified rasp with dulled blades named ‘Mild Rasp’, and analyzed with the statistical methods.

Introduction

Previous anthropometric studies have reported gender differences in distal femoral morphology. After total knee arthroplasty, females have a higher prevalence of medial or lateral femoral component overhang, which could be responsible for postoperative knee pain and decreased range of motion. Consequently, gender-specific knee prostheses were designed to accommodate female morphology. However, to date, very few studies have investigated the knee morphology of Japanese adults and possible gender differences. The purpose of this study was to examine the distal femoral morphology of Japanese patients, to characterize anatomical differences between men and women, and to evaluate the need to create gender-specific knee prostheses.

Material and Methods

We evaluated 107 knees in 17 male and 90 female Japanese patients for total knee arthroplasty (TKA)[fig.1]. The medial-lateral (ML) and anteroposterior (AP) dimensions of the knees at different levels evaluated intraoperative measurement, and ML/AP aspect ratios were calculated.

INTRODUCTION

Total knee arthroplasty (TKA) is one of the most successful and beneficial treatments for osteoarthritic knees. We have developed posterior-stabilized (PS) total knee prosthesis for Asian patients, especially Japanese patients, and have used it since November, 2010. The component was designed based on the CT images of osteoarthritic knees, aiming to achieve deep flexion and stability. The purpose of this study was to analyze in- vivo kinematics of this new prosthesis.

METHODS

We analyzed a total of 28 knees implanted with PS TKAs: Fourteen knees with the new PS prosthesis (group A), and the other fourteen knees with a popular PS prosthesis as a control group (group B). Preoperative data of both groups were not significantly difference. Flat-panel radiographic knee images were recorded during five static knee postures including full extension standing, lunge at 90° and maximum flexion, and kneeling at 90° and maximum flexion. The three-dimensional position and orientation of the implant components were determined using model-based shape matching techniques. The results of this shape-matching process have standard errors of approximately 0.5° to 1.0° for rotations and 0.5 to 1.0 mm for translations in the sagittal plane. Unpaired t-tests were used for statistical analysis and probability values less than 0.05 were considered significant.

Purpose

According to Bipolar Hemiarthroplasty of the Hip (BHA), several reports indicated earlier acquisition of walking ability in direct anterior approach (DAA) than posterior approach (PA), but there is still few randomized studies comparing accuracy of stem insertion in DAA and PA. Therefore, we performed a prospective study, focusing positioning of implant.

Patient and Methods

We chose 29 patients for this study, diagnosed as femoral neck fracture (Garden grade III or IV) from April 2012 to April 2013, excluding obesity patients (body mass index upper than 30kg/m²), muscular patients, osteoporotic patients (Sigh grade I or II), and tumor bearing patients. Patients were enrolled in a prospective, non-blinded study and were randomly assigned by envelope method to receive either DAA or PA. Taperloc BHA system (Zimmer) was adapted for all cases. Patient condition, operation condition and radiographic findings were investigated. On CT imaging, Canal fill was calculated Stem fill was studied at lower point of lesser trochanter that was considered to be load center. Static analysis was carried out using SPSS ver21 (IBM^c). Continuous variables between the two groups were compared using a no matched bilateral Student's t-test. For nominal variables we used χ²test. P value <0.05 was considered to be significant. (Table1)

Introduction

Computed tomography (CT) based preoperative planning provides useful information for severe TKA and revision TKA cases, such as the amount of augmentation, length of stem extension and component alignment, to achieve correct alignment and joint line. In this study, we evaluated TKA alignment performed with CT preoperative planning.

Materials and Methods

7 primary TKAs for severe deformity and 3 revision TKAs were included. CT preoperative planning was performed with JIGEN (LEXI, Japan). Constrained condylar prosthesis (LCCK, Zimmer) were used in all case. For femoral component, axial alignment was decided by controlled IM rod insertion to femoral canal. Rotational alignment was decided according to anterior cortex that usually was not compromised. For tibial component, axial alignment was set to perpendicular to tibial mechanical axis. Coverage and joint line level were carefully decided. The amount of bone resection of bilateral distal and posterior femoral condyle and proximal tibia was measured, respectively. Stem extension length and offset were selected according to components position and canal filling. Amount of augmentation was also estimated bilateral distal and posterior femoral condyle, respectively. Postoperative component alignment was evaluated three-dimensionally with Knee-CAS (LEXI, Japan).

Objectives

The efficacy of Gram-stain microscopy for diagnosis of septic arthritis is fundamentally limited by an inherent false-negative rate of 25–50%. The aim of this study was to calculate the sensitivity of Gram-stain microscopy of synovial fluid collected in heparinised containers and to investigate if this collection method improves diagnostic value.

Methods

12-year retrospective study of patients undergoing synovial fluid analysis between 1998 and 2010. Gram-stain result was correlated with culture result and clinical diagnosis. The formula sensitivity = number of true positives/(number of true positives + number of false negatives) was used for analysis.

Introduction

When performing total knee arthroplasty (TKA), surgeons often utilize a posterior-stabilized (PS) design which compensates for the loss of the posterior cruciate ligament (PCL). These designs attempt to replicate normal knee kinematics and loading using a cam and post to provide posterior restraint of the tibia during flexion. However, these designs may not be able to compensate for the increase in flexion space or the inherent loss of coronal stability after PCL release compared to a cruciate retaining (CR) design. This study aimed to compare stability of PS and CR TKA designs by assessing laxity in three planes.

Methods

The specimens utilized in this study were lower extremities from fresh cadavers of donors who had previously undergone a total knee replacement (Medical Education and Research Institute (Memphis, TN) and Restore Life USA (Johnson City, TN)). IRB approval was obtained prior to performing the study. Twenty-three knee specimens (8 left, 15 right) were retrieved and all skin, subcutaneous tissue and muscle was removed. The femur and tibia were cut transversely 180 mm superior and inferior to the knee joint line, respectively, and specimens were mounted in a custom knee testing machine. Specimens were tested with the knee joint at full extension and at 30, 60, and 90 degrees of flexion. Laxity was assessed at 1.5 Nm of internal and external torque and 10 Nm varus and valgus torque, as well as a 35 N anterior and posterior force. Laxity was expressed as degrees of tibial displacement in the coronal plane under a varus/valgus torque and degrees of displacement in the transverse plane under an internal/external torque, as well as mm of anterior or posterior displacement. TKA components were retrieved to determine PS or CR design and grouped accordingly.

Introduction

The sit-to-stand (STS) movement is a physically demanding activity of daily living and is performed more than 50 times per day in healthy adults. Several studies have shown that the normal ‘screw-home’ mechanism is altered after total knee arthroplasty (TKA). However, these studies have been criticized due to their limitations of the movement being non-weight-bearing or atypical daily activity (lunge maneuver). We analyzed TKA subjects during a STS activity to determine if the internal-external rotation of their TKA knees differed from the knees of control subjects.

Materials and Methods

Six TKA subjects (3 M, 3 F) participated following institutional review board approval and informed consent. One subject had bilateral knee replacement. Surgery was performed by the same surgeon using the same type of implant (6 posterior-stabilized, 1 cruciate-retaining). The control group included eight healthy subjects (6 M, 2 F).

Retro-reflective markers were placed over bony landmarks of the torso, pelvis, and lower extremities, and arrays of four markers were attached to the thighs and shanks using elastic wrap. A digitizing pointer was used to create virtual markers at the anterior superior iliac spines. A nine camera video-based opto-electronic system (Qualisys) was used for 3D motion capture. Subjects were barefoot and seated on a 46 cm armless bench with one foot on each force plate (AMTI). Subjects rose from their seated position, paused, and returned to the seated position at a self-selected pace repeatedly for 30 seconds. Subjects did not use their arms to push off the bench. Only the STS portion of the task was analyzed. The start of the STS cycle was defined when the C7 marker began to move forward in the sagittal plane and ended at the point of maximum knee extension. Only the right leg of the control subjects was used for analysis.

Introduction

In a previous study of subjects with no history of lower extremity injury or disease we found a linear relationship between body weight and peak hip, knee, and ankle joint forces during the stance phase of gait. To investigate the effect of total knee arthroplasty (TKA) on forces in the operated joints as well as the other joints of the lower extremities, we tested TKA subjects during gait and performed inverse dynamics analyses of the results.

Materials and Methods

TKA subjects (3 M, 1 F; 58 ± 5 years; body mass index range (BMI): 26–36 kg/m²) participated in this investigation following institutional review board approval and informed consent. One subject had bilateral knee replacement. Each patient received the same implant design (4 PS, 1 CR). Data from previously tested control subjects (8 M, 4 F; 26 ± 4 years; BMI: 20–36 kg/m²) were used for comparison.

Retro-reflective markers were placed over bony landmarks of each subject. A nine-camera video-based opto-electronic system was used for 3D motion capture as subjects walked barefoot at a self-selected speed on a 10 meter walkway instrumented with three force plates. Data were imported into a 12-body segment multibody dynamics model (AnyBody Technology) to calculate joint forces. Each leg contained 56 muscles whose mechanical effect was modeled by 159 simple muscle slips, each consisting of a contractile element. The models were scaled to match each subject's anthropometry and BMI. For the control subjects, only one limb was used in determining the relationship between body mass and peak joint force at the hip, knee, and ankle. For the TKA subjects, the peak joint forces were calculated for both the TKA limb and the contralateral limb.

Background

Total knee arthroplasty is associated with early postoperative pain. Appropriate pain management is important to facilitate postoperative rehabilitation and positive functional outcomes. This study compares outcomes in TKA with three techniques; local infiltration analgesia, single shot femoral nerve block and intrathecal morphine.

Methods

Forty-five patients undergoing elective primary Total Knee Arthroplasty (TKA) with were randomized into one of three groups in a double blind proof of concept study. Study arm 1 received local infiltration analgesia ropivacaine intra-operatively, an elastomeric device of ropivacaine for 24 hours post-op. Study arm 2 received a femoral nerve block of ropivacaine with placebo local infiltration analgesia and placebo intrathecal morphine. Study arm 3 received intrathecal morphine, placebo femoral nerve block and placebo local infiltration analgesia. All patients received standardized pre-operative, intraoperative and Post-operative analgesic medication.

Participants were mobilized at 4 hrs, 24hrs and 48 hrs post operation. Range of Motion, Visual Analogue Scale (VAS) pain intensity scores and two minute walk test and Timed Up and Go test were performed. Postoperative use of analgesic drugs was recorded. Knee Society Score (KSS), Oxford Knee Score and Knee Injury and Osteoarthritis Outcome Score (KOOS) were completed at preoperative and 6 weeks post op.

Background

Shoulder impingement syndrome (SIS) is a common debilitating condition, treated across multiple health disciplines including Orthopaedics, Physiotherapy, and Rheumatology. There is little consistency in diagnostic criteria with ‘Shoulder impingement syndrome’ being used for a broad spectrum of complex pathologies. We assessed patterns in diagnostic procedures for SIS across multiple disciplines.

Methods

This is a systematic review of electronic databases MEDLINE, PubMed, The Cochrane Library, Embase, Scopus and CINAHL five years of publications, January 2009 - January 2014. Search terms for SIS included subacromial impingement syndrome, subacromial bursitis. Searches were delimited to articles written in English. The PRISMA guidelines were followed. Two reviewers independently screened all articles, data was then extracted by one reviewer and twenty percent of the extraction was independently assessed by the co-reviewer. Studies included were intervention studies examining individuals diagnosed with SIS and we were interested in the process and method used for the diagnosis.

Introduction

Currently, there is a focus on the development of novel materials to articulate against cartilage. Such materials should either eliminate or delay the necessity of total joint replacement. While cobalt-chromium (CoCr) alloy is still a material of choice and used for hemi-arthroplasties, spacers, and repair plugs, alternative materials are being studied. Pyrolytic carbon (PyC) is a biocompatible material that has been available since the 1980s. It has been widely and successfully used in small joints of the foot and the hand, but its tribological effects in direct comparison to cobalt-chromium (CoCr) remain to be investigated.

Methods

A four station simulator (Figure 1), mimicking joint load and motion, was used for testing. The simulator is housed in an incubator, which and provides the necessary environmental conditions for cartilage survival. Articular cartilage disks (14mm in diameter) were obtained from the trochleas of six to eight months old steer for testing and free-swelling controls. Disks (n=8 per material) were placed in porous polyethylene scaffolds within polypropylene cups and mounted onto the simulator to articulate against 28mm balls of either PyC or CoCr. Each ball was pressed onto the cartilage disk with 40N. In order to allow fluidal load support, the contact migrated over the biphasic cartilage with a 5.2 mm excursion. Concomitantly, the ball oscillated with ±30° at 1 Hz. Testing was conducted for three hours per day over 10 days in Mini ITS medium. Media samples were collected at the end of each three hour test. Upon test commencement, media was pooled (days 1, 4, 7, 10) and analyzed for proteoglycans/sGAGs and hydroxyproline. In addition, total material release into media was estimated by determining the dry weight increase of media samples. For this purpose, 1 ml aliquots of fresh and test media were dialyzed, lyophilized and weighed on a high precision balance. Disk morphology and cell viability were histologically examined.

Introduction

Current pre-clinical testing is performed using knee wear simulators with standardized walking profiles. Differences in generated damage patterns to those observed on retrieved liners have been explained with the absence of activities other than walking, less severe loading conditions, and a discrepancy in the simulator's tibiofemoral contact mechanics and in vivo knee excursion. While it has been recognized that rotational alignment of the knee may also drive the location and shape of wear scars, to the best of our knowledge this parameter has not been investigated in knee simulator studies.

Methods

Here, we use patient specific gait as input to the simulation to approximate the patient specific contact mechanics. Kinematic and kinetic input data was obtained from gait analysis of a patient with a MGII (Zimmer Inc.) prosthesis at 11 years post-op using the point cluster technique for tibiofemoral kinematics, and a mathematical model for internal force calculations. Using the identical type of prosthesis on the simulator, wear tests were conducted in displacement mode on a closed-loop controlled station. Because x-rays of the patient suggested an internal rotation of the tibial tray, it was varied form 0–10° and the effect on location and wear scar dimension was assessed. Results were compared with the retrieved liner (obtained after 13 years in vivo).

Purpose

The purpose of this study was to evaluate the short to mid-term results after hemiarthroplasty with extended head prosthesis (CTA head) for patients with cuff tear arthopathy.

Hypothesis

Favorable pain reduction would be obtained after hemiarthroplasty with the extended head design.

Introduction

Clione Anchored Replacement Prosthesis (CARP-H system) is a novel femoral implant for cementless fixation at the metaphysis of the proximal femur and preservation of cancellous bone of the femoral diaphysis is expected (Fig.1). We developed CARP-H system and started to use the prosthesis after the approval by Pharmaceuticals and Medical Devices Agency in 2012. This study examines the efficacy and short-term outcome of CARP-H system in a series of patients undergoing total hip arthroplasty (THA) or bipolar hemi-arthroplasty (BHA).

Patients and Methods

Seventeen patients (17 hips) of osteonecrosis of the femoral head (ON) or osteoarthritis of the hip (OA) were included. The diagnoses were OA in 10 patients, and ON in 7 patients. The mean age at surgery was 55 years (35–62 years). The mean follow-up was 12 months (6–19 months). THA using CARP-H system was performed in 11 hips and BHA in 6 hips.

Purpose

In vivo comparative gap measurements were performed in 3 different patella positions (reduced, subluxated and everted) using offset-type-force-controlled-spreader-system.

Methods

Prospectively, 50 knees were operated by TKA using a navigation-assisted gap balancing technique. The offset-type-force-controlled-spreader-system was used for gap measurements. This commercially-available instrument allows controllable tension in patella reduced position. The mediolateral gaps of knee extension (0°) and flexion (90°) angle were recorded in 3 different patella positions; reduced, subluxated and everted. Any gap differences of more than 3 mm were considered as a meaningful difference. Correlation between the difference with the demographic data, preoperative radiologic alignment and intraoperative data was analyzed. For statistical analysis, ANOVA and Pearson correlation test were used.

Conclusion

The use of non-opioid transdermal patches is a safe and patient-activated method. Non-opioid transdermal patches show NSD improvement in the postoperative pain control for patients underwent TKA, facilitating fewer narcotics consumption, fewer breakthrough pain, faster recovery in movements and even shorter stay. However, without obvious differences, the routine use of transdermal patches in current pain control protocol should be trade-off.

Background

Previously, the Coonrad-Morrey elbow system has typically been performed using linked-type total elbow arthroplasty (TEA) implants. However, this implant have been reported to be associated with some problems, such as wearing down, loosening, the complexity of the necessary surgical techniques and inappropriate implant size for Asian people.

The Discovery elbow system (Biomet Inc., Warsaw, US) has recently been developed and it has many advantages when compared to Coonrad-Morrey implant, but the treatment outcome for this system is unclear in patients with rheumatoid arthritis (RA).

Objectives

The aim of this study was to clarify the outcome of TEA using the Discovery elbow system.

Introduction

In total knee arthroplasty, the alignment of leg depends on the alignment of the component. In unicompartmental knee arthroplasty, it is determined by the thickness of the implant relative to the bone excised mostly. After initial scepticism, UKA is increasingly accepted as a reliable procedure for unicompartmental knee osteoarthritis with the improvements in implant design, surgical technique and appropriate patient selection. Recently, computer assisted UKA is helpful in accuracy and less invasive procedure. But, fixed bearing or mobile bearing in UKA is still controversy. We compared the early clinical and radiological results of robot-assisted unicompartmental knee arthroplasty using a fixed bearing design versus a mobile type bearing design.

Materials and Methods

A data set of 50 cases of isolated compartmental degenerative disease that underwent robot-assisted UKA using a fixed bearing design were compared to a data set of 50 cases using a mobile bearing type design. The operations were performed by one-senior author with the same robot system. The clinical evaluations included the Knee Society Score (knee score, functional score) and postoperative complications. The radiological evaluations was assessed by 3-foot standing radiographs using the technique of Kennedy and White to determine the mechanical axis and femoro-tibial angle for knee alignment. Operative factors were evaluated including length of skin incision, operation time, blood loss, hospital stay and intraoperative complications.

Purpose

Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) is subjective assessment of coxarthropathy and reflects the satisfaction level of the patient. Recently, the use of JHEQ as a postoperative assessment of total hip arthroplasty (THA) has become widespread. The aim of this study was to investigate the clinical outcomes of bilateral simultaneous THA through the direct anterior approach (DAA) using JHEQ.

Methods

This study included 34 patients (41 hips) who were treated with first THA at our hospital from January to March 2013 and were available for evaluation of clinical outcomes 1 year after surgery. Of these, 7 (2 males and 5 females; mean age, 54.7 years) underwent bilateral simultaneous THA (group B), and 27 (2 males and 25 females; mean age, 64.2 years) underwent unilateral THA (group U). Thirty patients were preoperatively diagnosed with hip osteoarthritis, and 4 were diagnosed with avascular necrosis of the femoral head. All patients were treated through DAA in a supine position under general anaesthesia. Items for evaluation included clinical outcomes, Japanese Orthopaedic Association Hip score (JOA score) and JHEQ.

Introduction

Unicompartmental knee arthroplasty(UKA) has become a popular treatment alternative when one compartment of the knee is affected. Excellent intermediate results have been reported in association with the Miller-Galante unicompartmental implant. These excellent results are based on the development of the implants and the stringent patients selection. The functional cruciate ligaments has been a prerequisite for patients undergoing UKA. However, UKA can be one of the procedures in elderly patiants with deficient anterior cruciate ligaments(ACL) but with no symptoms of instability. The purpose of this report is to determine the clinical results after UKA in patients with ACL-deficient knees and compared those after UKA in ACL-intact knees.

Patients and Methods

We identified 332 cases operated from May 2000 to April 2013 whose ACL were evaluated before the operation by MRI., and classified into ACL-deficient group and ACL-intact group. Fixed-bearing Miller-Galante Unicompartmental Knee System or Zimmer Unicompartmental High-Flex Knee Sytem was implanted in all patients. ACL-deficient group included 17 men and 68 women who had an average age of 79 years(range, 70–91 years) at the time of the operation. The underlying diagnosis was osteoarthritis for 77 knees and osteonecrosis for 8 knees. ACL-intact group included 49 men and 198 women who had an average age of 77 years(range, 60–88 years) at the time of the operation. The underlying diagnosis was osteoarthritis for 176 knees and osteonecrosis for 71 knees. Followup for ACL-deficient group was 3.5 years(1–8.8years), and 3.6years (1–13.2years) for ACL-intact group.

Purpose

To measure the vitamin D level of the patients who received total knee arthroplasty (TKA) and evaluate the effect of vitamin D level on the results of TKA.

Materials and Methods

From February 2012 to January 2013, 151 female patients (204 knees) who underwent primary TKA by one surgeon were included in our study. Preoperative vitamin D level was measured and analyzed the relationship between that and preoperative Visual Analogue Scale (VAS), and Knee Society Knee Score (KS) and Function Score (FS). Thirty-nine patients (39 knees) who received unilateral TKA and could be followed up more than 1 year after operation were evaluated for the relationship between vitamin D level and postoperative VAS, KS and FS, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score.

INTRODUCTION

Trabecular Titanium^™ (TT) is a novel material with a structure similar to trabecular bone, already used for prosthetic clinical applications. Being the bone-implant interface the weakest point during the initial healing period, the association of TT with a hydrogel enriched with progenitor cells and osteoinductive factors may represent a promising strategy to improve prosthesis osteointegration. In a previous in vitro study we evaluated the ability of an ammidated carboxymethylcellulose hydrogel (CMCA) and of TT enriched with CMCA to support bone marrow mesenchymal stem cells (BMSCs) viability and osteogenic differentiation [1]. The aim of this study was to evaluate in vivo if the association of TT with CMCA enriched with strontium chloride (SrCl₂) and BMSCs could ameliorate TT osteointegration.

METHODS

This study combines TT with CMCA, SrCl₂ and BMSCs. To mimic prosthesis-bone implants, TT discs were seeded with human BMSCs predifferentiated in osteogenic medium, then press-fit into engineered bone. A total of 36 athymic mice were implanted subcutaneously, each animal received 2 constructs as un-seeded TT and TT+CMCA or cell seeded TT+BMSCs and TT+CMCA+BMSCs. After 4, 8 and 12 weeks, osteodeposition, bone mineral density (BMD) and osteointegration were evaluated by fluorescence imaging, micro-CT, SEM, histology and pull-out tests.

Introduction

Allogeneic blood transfusion (ABT) remains a widely used therapeutic intervention in patients undergoing total knee arthroplasty (TKA). There is mounting evidence that tranexamic acid (TXA), a powerful antifibinolytic, can significantly reduce perioperative blood loss with a concomitant lower ABT rate. In May 2012, TXA intravenous infusion was introduced as standard therapy in all patients undergoing major hip and knee arthroplasty. The TXA protocol included infusing 1 gm prior to incision and 1 gm after lowering the tourniquet. Nadir hemoglobin (Hb) level has been shown to be the single most important predictor of ABT in patients undergoing TKA. It is often used as the main trigger for ABT and in research trials examining restrictive transfusion trials. There is a paucity of information regarding the impact of TXA on Hb levels in patients undergoing primary TKA. The purpose of this retrospective study was to examine the impact of TXA on hemoglobin levels in primary TKA patients.

Methods

Patients undergoing primary single, or bilateral, TKA from a single orthopedic surgeon from the years 2009–2010 before TXA infusion (n=78) were compared to patients undergoing the same operation after TXA was introduced as a therapeutic intervention (n=97). TKA is a very standardized operation that has stayed consistent over the convening years in terms of surgical technique and intra-operative management. The following Hb values were selected for analysis between the two groups: pre-surgical Hb value, immediate post-operative Hb, nadir Hb, and discharge Hb. Paired t-test was used for analysis with p-value set at 0.05. Additional data analysis included: length of stay (LOS) and rate of ABT.

Conclusion

Overall, the average post-operative range of movements in both groups is not very significant different. Bio-RSA without bone graft seems to make a larger improvement when compared with per-operative range of motion. Howver, whether a much longer follow-up period and younger patients have an impact on the outcome is debatable.

Background

The development of T-smart tomosynthesis has greatly improved the imaging quality of THA by reducing the peri-implant artifacts. In order to find out whether these improvements could lead to diagnostic advantages on stability of cementless THA arthroplasty components, we conducted a diagnostic research by comparing T-smart tomosynthesis, X-ray, and computed tomography.

Methods

We retrospectively included 48 patients who undergone THA revisions in our center between Aug, 2013 and Mar, 2014. For patients with hybrid fixation as their primary prosthesis, the femoral or acetabular components with cement fixation were excluded. There were 41 cementless femoral stems and 35 cementless acetabular cups remained for evaluation. All patients took anterior-posterior and lateral view x-ray examination, anterior-posterior T-smart tomosynthesis scan, and computed tomography before revision surgery. As the gold standard, intraoperative pull-out tests and twisting tests were done for every patient to examine the stability of all implants. 7 orthopedic surgeons evaluated the preoperative images independently, who were divided into the senior group (3 doctors with 6∼13 years’ clinical experience) and the junior group (4 doctors with 2∼4 years’ clinical experience). The x-rays were evaluated first, followed by computed tomography 4 weeks later, and after another 4 weeks’ interval the T-smart tomosynthesis were assessed. All doctors used the same criteria for diagnosis. Diagnostic accuracy for each imaging examination was calculated by comparing with the results of intraoperative tests. The diagnostic accuracy, kappa values between 3 imaging techniques were calculated, and chi-square tests were conducted to examine the difference between the senior and junior groups for each technique.

Introduction

There are several advantages of unicompartmental knee arthroplasty (UKA) in the treatment of isolated compartment osteoarthritis (OA) compared to the conventional total knee arthroplasty. Although various series report similar survivorship results, the national registries tend to show higher revision rates among the UKA. Persisting, unexplainable pain is a leading cause for UKA revision surgery. Therefore it is essential to investigate the various patient specific characteristics which might influence outcome following UKA in order to minimize revision rates and optimize clinical outcomes. The purpose of this study is to evaluate the influence of the various individual patient factors, including pre-operative radiographic parameters, on the outcome following UKA.

Methods

168 consecutive patients who underwent robot assisted UKA (MAKO Tactile Guidance System, MAKO Surgical Corporation, Ft. Lauderdale, FL, USA) were included. The investigated pre- and/or postoperative parameters included gender, BMI, age, type of tibial implant (inlay versus onlay), laterality, state of OA (i.e. Kellgren and Lawrence grade) of the operated and non-operated compartment and mechanical axis alignment.

Pre-operatively and at a minimum of 1 year (average 1.97 years, range 1 – 4.2 years) following surgery, patients were asked to complete the Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire. It is subdivided in three separate scales (i.e. pain, stiffness and function). A score of 0 represents the best possible outcome and a score of 100 the worst. A p-value <0.05 was considered statistically significant.

Introduction

Chronic uneven distribution of forces over the articular cartilage, which are present in OA, has been shown to be a risk factor for the development of OA. Certain regions of the articular cartilage will be exposed to increased chronic peak loads, whereas other regions encounter a corresponding relative reduction of transmitted forces. This has a well known influence on cartilage viability and is a precursor of degenerative progression. Congruence of joints has an important impact on force distribution across articular surfaces. Therefore, tibiofemoral incongruence could lead to alterations of load distribution and ultimately to progressive degenerative changes. In clinical practice the routine method for evaluation of progressive OA is analysis of joint space width (JSW) using weight bearing radiographs. Recent studies have suggested that JSW has a strong positive correlation with cartilage compression, volume and meniscal extrusion

Lateral unicondylar knee arthroplasty (UKA) has gained increasing popularity over the last decade in the treatment of isolated unicompartmental osteoarthritis (OA). However, progressive degenerative alterations of the medial compartment following lateral unicompartmental knee arthroplasty remains a leading cause of revision surgery. Therefore, the purpose of this study is to evaluate the medial compartment congruence (MCC) and joint space width (JSW) alterations following lateral UKA.

Methods

The MCC of 53 knees following lateral UKA was evaluated on pre- and postoperative radiographs and compared to 41 healthy knees, using an Interative Closest Point (ICP) algorithm. The ICP algorithm calculated the Congruence Index (CI) by performing a rigid transformation that best aligns the digitized tibial and femoral surfaces (figure 1A). Inner, middle and outer JSW was measured by subdividing the medial compartment into four quarters on weight bearing tunnel view radiographs pre- and postoperatively (figure 1B).

Introduction

Historically, the outcomes of knee replacement were evaluated based on implant longevity, major complications and range of motion. Over the last recent years however, there has been an intensively growth of interest in the patient's perception of functional outcome. However, the currently used patient related outcome (PRO) scores are limited by ceiling effects which limit the possibility to distinguish between good and excellent results post knee arthroplasty. The Forgotten Joint Score (FJS) is a new PRO score which is not influenced by ceiling effects, therefore making it the ideal instrument to compare functional outcome between various types of implants. It is based on the thought that the ultimate goal in joint arthroplasty is the ability of a patient to forget their artificial joint in everyday life.

The aim of this study is to compare the FJS between patients who undergo TKA and patients who undergo medial UKA at least 12 months post-operatively. We hypothesized that the UKA which is less extensive surgical procedure will present better FJS than TKA, even 12 month postoperative.

Methods

All patients who underwent medial UKA or TKA were contacted 12 months post-operatively. They were asked to complete the FJS, the Western Ontario and McMasters Universities Osteoarthritis index (WOMAC) and the EuroQol-5D (EQ-5D). A priori power analysis was conducted using two-sample t-test. 64 patients in each group were needed to reach 80% power for detecting a 12 point (SD 24) significant difference on the FJS scale with a two-sided significant level of 0.05. A p-value <0.05 was considered as statistically significant.