The purpose of this study was to assess the success rate and functional outcomes of bone grafting for periprosthetic bone cysts following total ankle arthroplasty (TAA). Additionally, we evaluated the rate of graft incorporation and identified associated predisposing factors using CT scan. We reviewed a total of 37 ankles (34 patients) that had undergone bone grafting for periprosthetic bone cysts. A CT scan was performed one year after bone grafting to check the status of graft incorporation. For accurate analysis of cyst volumes and their postoperative changes, 3D-reconstructed CT scan processed with 3D software was used. For functional outcomes, variables such as the Ankle Osteoarthritis Scale score and the visual analogue scale for pain were measured.Aims
Methods
We have previously reported on the medium-term outcomes following a non-operative protocol of a short period of splinting followed by early movement to treat simple dislocations of the elbow. We undertook extended follow up of our original patient study group to determine whether the excellent results previously reported were maintained in the very long-term. A secondary question was to determine the rate and need for any late surgical intervention. We attempted to contact all patients in the original patient study group. Patients were requested to complete the Oxford elbow score (OES), the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and a validated patient satisfaction questionnaire. Patients were requested to attend a face-to-face assessment where they underwent a clinical examination including neurovascular assessment, range-of-motion and an assessment of ligamentous stability. Seventy-one patients (65%) from the original patient study group agreed to participate in the study. The mean duration of follow-up was 19.3 years. At final follow-up patients reported excellent functional outcome scores and a preserved functional range of movement in the injured elbows. The mean DASH score was 5.22 points and the mean Oxford Elbow Score was 91.6 points. The mean satisfaction score was 90.9 points. Our study shows that the excellent outcomes following treatment with a protocol of a short period of splinting and early movement remain excellent and are maintained into the very long term. These findings support our hypothesis that this treatment protocol is appropriate and suitable for most patients with simple dislocations of the elbow. The role for primary ligamentous repair for this patient group should be carefully considered. Work to more clearly define the anticipated benefits of surgery for specific patient groups or injury patterns would help to support informed decision making.
We undertook this study to investigate the outcomes of surgical treatment for acute carpal tunnel syndrome following our protocol for concurrent nerve decompression and skeletal stabilization for bony wrist trauma to be undertaken within 48-hours. We identified all patients treated at our trauma centre following this protocol between 1 January 2014 and 31 December 2019. All patients were clinically reviewed at least 12 months following surgery and assessed using the Brief Michigan Hand Outcomes Questionnaire (bMHQ), the Boston Carpal Tunnel Questionnaire (BCTQ) and sensory assessment with Semmes-Weinstein monofilament testing. The study group was made up of 35 patients. Thirty-three patients were treated within 36-hours. Patients treated with our unit protocol for early surgery comprising nerve decompression and bony stabilization within 36-hours, report excellent outcomes at medium term follow up. We propose that nerve decompression and bony surgical stabilization should be undertaken as soon as practically possible once the diagnosis is made. This is emergent treatment to protect and preserve nerve function. In our experience, the vast majority of patients were treated within 24-hours.
Neither a surgeon’s intraoperative impression nor the parameters of computer navigation have been shown to be predictive of the outcomes following total knee arthroplasty (TKA). The aim of this study was to determine whether a surgeon, with robotic assistance, can predict the outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (KPS), one year postoperatively, and establish what factors correlate with poor KOOS scores in a well-aligned and balanced TKA. A total of 134 consecutive patients who underwent TKA using a dynamic ligament tensioning robotic system with a tibia first resection technique and a cruciate sacrificing ultracongruent TKA system were enrolled into a prospective study. Each TKA was graded based on the final mediolateral ligament balance at 10° and 90° of flexion: 1) < 1 mm difference in the thickness of the tibial insert and that which was planned (n = 75); 2) < 1 mm difference (n = 26); 3) between 1 mm to 2 mm difference (n = 26); and 4) > 2 mm difference (n = 7). The mean one-year KPS score for each grade of TKA was compared and the likelihood of achieving an KPS score of > 90 was calculated. Finally, the factors associated with lower KPS despite achieving a high-grade TKA (grade A and B) were analyzed.Aims
Methods
The response to the COVID-19 pandemic has raised the profile and level of interest in the use, acceptability, safety, and effectiveness of virtual outpatient consultations and telemedicine. These models of care are not new but a number of challenges have so far hindered widespread take-up and endorsement of these ways of working. With the response to the COVID-19 pandemic, remote and virtual working and consultation have become the default. This paper explores our experience of and learning from virtual and remote consultation and questions how this experience can be retained and developed for the future. Cite this article:
Excessive standing posterior pelvic tilt (PT), lumbar spine stiffness, low pelvic Incidence (PI), and severe sagittal spinal deformity (SSD) have been linked to increased dislocation rates. We aimed to compare the prevalence of these 4 parameters in unstable and stable primary Total Hip Arthroplasty (THA) patients. In this retrospective cohort study, 40 patients with instability following primary THA for osteoarthritis were referred for functional analysis. All patients received lateral X-rays in standing and flexed seated positions to assess functional pelvic tilt and lumbar lordosis (LL). Computed tomography scans were used to measure pelvic incidence and acetabular cup orientation. Literature thresholds for “at risk” spinopelvic parameters were standing pelvic tilt ≤ −10°, lumbar flexion (LLstand – LLseated) ≤ 20°, PI ≤ 41°, and sagittal spinal deformity (PI – LLstand mismatch) ≥ 10°. The prevalence of each risk factor in the dislocation cohort was calculated and compared to a previously published cohort of 4042 stable THA patients.Introduction
Methods
Neither a surgeon's intraoperative impression or computer navigation parameters have been shown to be predictive of postoperative outcomes following TKA. The purpose of this study is to determine 1) whether a surgeon and a robot can predict the 1-year KOOS pain score (KPS) and 2) determine what factors correlate with poor KOOS scores in well aligned and balanced TKA. The data of 131 consecutive patients enrolled in a prospective trial was reviewed. All TKAs were performed using a dynamic ligament tensioning robotic system with a tibial first resection technique and a cruciate sacrificing ultracongruent knee implant. Each TKA was graded based on the final recorded mediolateral ligament balance at 10° and 90°: A) <1mm with an implanted insert thickness equal to planned (n=74); B) <1mm (n=25); C) <2mm (n=26); D) >2mm (n=6) (Table-1). The 1-year KPS for each knee grade were compared and the likelihood of achieving an KPS > 90 was calculated. Finally, the factors associated with lower KPS despite achieving a high grade TKA (A/B) was performed. The Mann-Whitney U test and Chi-squared analysis was performed.Introduction
Methods
The prevalence of the various patterns of spinopelvic abnormalities that increase the risk for prosthetic impingement is unknown. While prior surgery or lumbar fusion are recognized as a risk factors for postoperative dislocation, many patients presenting for THA do not have obvious radiographic abnormalities. The purpose of this study is to determine the prevalence of large posterior pelvic tilt (PPT) when standing, stiff lumbar-spine (SLL) and spino-pelvic sagittal imbalance (SSI) in patients undergoing primary THA. A consecutive series of 1592 patients (56% female) over 2 years underwent functional analysis of spinopelvic mobility using CT, standing, and flexed seated lateral radiographs as part of pre-operative THA planning. The average age was 65 (20–93). We investigated the prevalence of these 3 validated spinopelvic parameters known to increase the risk for impingent and correlated them to the patient's age and gender using Chi squared analysis. Finally, the risk of flexion and extension impingement was modeled for each patient at a default supine cup orientation (DSCO) of 40°/20° (±5°).Introduction
Methods
Surgical management of PJI remains challenging with patients failing treatment despite the best efforts. An important question is whether these later failures reflect reinfection or the persistence of infection. Proponents of reinfection believe hosts are vulnerable to developing infection and new organisms emerge. The alternative hypothesis is that later failure is a result of an organism that was present in the joint but was not picked up by initial culture or was not a pathogen initially but became so under antibiotic pressure. This multicenter study explores the above dilemma. Utilizing next-generation sequencing (NGS), we hypothesize that failures after two stage exchange arthroplasty can be caused by an organism that was present at the time of initial surgery but not isolated by culture. This prospective study involving 15 institutions collected samples from 635 revision total hip (n=310) and knee (n=325) arthroplasties. Synovial fluid, tissue and swabs were obtained intraoperatively for NGS analysis. Patients were classified per 2018 Consensus definition of PJI. Treatment failure was defined as reoperation for infection that yielded positive cultures, during minimum 1-year follow-up. Concordance of the infecting pathogen cultured at failure with NGS analysis at initial revision was determined.Introduction
Methods
The aim of this study was to evaluate the performance of metagenomic next-generation sequencing (mNGS) in detecting pathogens from synovial fluid of prosthetic joint infection (PJI) patients. A group of 75 patients who underwent revision knee or hip arthroplasties were enrolled prospectively. Ten patients with primary arthroplasties were included as negative controls. Synovial fluid was collected for mNGS analysis. Optimal thresholds were determined to distinguish pathogens from background microbes. Synovial fluid, tissue, and sonicate fluid were obtained for culture.Aims
Methods
The integrity of the soft tissue envelope is crucial for successful treatment of infected total knee arthroplasty (TKA). The purpose of this study was to evaluate the rate of limb salvage, infection control, and clinical function following microvascular free flap coverage for salvage of the infected TKA. We retrospectively reviewed 23 microvascular free tissue transfers for management of soft tissue defects in infected TKA. There were 16 men and seven women with a mean age of 61.2 years (39 to 81). The median number of procedures performed prior to soft tissue coverage was five (2 to 9) and all patients had failed at least one two-stage reimplantation procedure. Clinical outcomes were measured using the Knee Society Scoring system for pain and function.Aims
Methods
It is well accepted that larger heads provide more stability in total hip arthroplasty. This is due to an increase in jump height providing increased resistance to subluxation. However, other implant parameters also contribute to the bearing's stability. Specifically, the liner's rim design and the centre of rotation relative to the liner's face. Both these features contribute to define the Cup Articular Arc Angle (CAAA). The CAAA describes the degree of dysplasia of the acetabular liner, and plays an important role in defining the jump height. The aim of this study was to determine the difference in jump height between bearing materials with a commonly used acetabular implant system. From 3D models of the Trinity acetabular implant system (Corin, UK), the CAAA was measured in CAD software (SolidWorks, Dassault Systems, France) for the ceramic, poly and modular dual mobility (DM) liners, for cup sizes 46mm to 64mm. The most commonly used bearing size was used in the analysis of each cup size. For the ceramic and poly liners, a 36mm bearing was used for cups 50mm and above. For the 46mm and 48mm cups, a 32mm bearing was used. The DM liners were modelled with the largest head size possible. Using a published equation, the jump height was calculated for each of the three bearing materials and each cup size. Cup inclination and anteversion were kept constant.Introduction
Methods
Infection following TKA can be a catastrophic complication that can cause significant pain, morbidity and jeopardize limb viability. The integrity of the soft tissue envelope is critical to successful treatment and infection control. While local tissue flaps can provide adequate coverage for most soft tissue defects around the knee, there are cases that require salvage using microvascular free tissue transfers. The purpose of this study is to evaluate the 1) rate of limb salvage; 2) infection control; and 3) clinical function following free flap coverage for salvage of the infected TKA. We retrospectively reviewed 23 microvascular free tissue transfers for management of soft tissue defects in infected TKA. There were 16 men and 7 women with a mean age of 61.2 years (range 39–81). The median number of procedures performed prior to soft tissue coverage was 5 (range 2–9) and all patients had failed at least one 2 stage reimplantation procedure. Clinical outcomes were measured using the Knee Society Scoring system for pain and function. The rate of limb salvage and infection control were recorded.Introduction
Materials and Methods
Total hip arthroplasty (THA) is gaining popularity as a treatment for displaced femoral neck fractures (FNFs), especially in physiologically younger patients. While THA for osteoarthritis (OA) has demonstrated low complication rates and increased quality of life, results of THA for acute FNF are not as clear. Currently, a THA performed for FNF is included in an institutional arthroplasty bundle without adequate risk adjustment, potentially placing centres participating in fracture care at financial disadvantage. The purpose of this study is to report on perioperative complication rates after THA for FNF compared with elective THA performed for OA of the hip. The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database between 2008 and 2016 was queried. Patients were identified using the THA Current Procedural Terminology (CPT) code and divided into groups by diagnosis: OA in one and FNF in another. Univariate statistics were performed. Continuous variables were compared between groups using Student’s Aims
Patients and Methods
Arthrosis of the hip joint can be a significant source of pain and dysfunction. While hip replacement surgery has emerged as the gold standard for the treatment of end stage coxarthrosis, there are several non-arthroplasty management options that can help patients with mild and moderate hip arthritis. Therefore, the purpose of this paper is to review early prophylactic interventions that may help defer or avoid hip arthroplasty. Nonoperative management for the symptomatic hip involves minimizing joint inflammation and maximizing joint mobility through intra-articular joint injections and exercise therapy. While weight loss, activity modifications, and low impact exercises is generally recommended for patients with arthritis, the effects of these modalities on joint strength and mobility are highly variable. Intra-articular steroid injections tended to offer reliable short-term pain relief (3–4 weeks) but provided unreliable long-term efficacy. Additionally, injections of hyaluronic acid do not appear to provide improved pain relief compared to other modalities. Finally, platelet rich plasma injections do not perform better than HA injections for patients with moderate hip joint arthrosis. Primary hip joint arthrosis is rare, and therefore treatment such as peri-acetabular osteotomies, surgical dislocations, and hip arthroscopy and related procedures are aimed to minimise symptoms but potentially aim to alter the natural history of hip diseases. The state of the articular cartilage at the time of surgery is critical to the success or failure of any joint preservation procedures. Lech et al. reported in a series of dysplastic patients undergoing periacetabular osteotomies that one third of hips survived 30 years without progression of arthritis or conversion to THA. Similarly, surgical dislocation of the hip, while effective for treatment of femoroacetabular impingement, carries a high re-operation rate at 7 years follow up. Finally, as the prevalence of hip arthroscopic procedures continues to rise, it is important to recognise that failure to address the underlying structural pathologies can lead to failure and rapid joint destruction. In summary, several treatment modalities are available for the management of hip pain and dysfunction in patients with a preserved joint space. While joint preservation procedures can help improve pain and function, they rarely alter the natural history of hip disease. The status of the articular cartilage at the time of surgery is the most important predictor of treatment success or failure.
Infection following total knee arthroplasty (TKA) can cause significant morbidity to the patient and be associated with significant costs and burdens to the healthcare system. Wound complications often initiate the cascade that can eventually lead to deep infection and implant failure. Galat et al. reported that wound complications following TKA requiring surgical treatment were associated with 2-year cumulative risks of major reoperation and deep infection of 5.3% and 6.0%, respectively. Consequently, developing a systematic approach to the management of wound problems following TKA can potentially minimise subsequent complications. Unlike the hip, the vascular supply to the soft tissue envelope to the knee is less robust and more sensitive to the trauma of surgery. Therefore, proper soft tissue handling and wound closure at the time of surgery can minimise potential wound drainage and breakdown postoperatively. Kim et al. showed, using a meta-analysis of the literature, that primary skin closure with staples demonstrated lower wound complications, decreased closure times, and lower resource utilization compared to sutures. However, a running subcuticular closure enables the most robust skin perfusion following TKA. Finally, the use of hydrofiber surgical dressings following surgery was associated with increased patient comfort and satisfaction and reduced the incidence of superficial surgical site infection. A wound complication following TKA needs to be managed systematically and aggressively. A determination of whether the extent of the involvement is superficial or deep is critical. Antibiotics should not be started without first excluding the possibility of a deep infection. Weiss and Krackow recommended return to the operating room for wound drainage persisting beyond 7 days. While incisional negative pressure wound therapy can occasionally salvage the “at risk” draining wound following TKA, its utilization should be limited only to the time immediately following surgery and should not delay formal surgical debridement, if indicated. Finally, early wound flap coverage and co-management of wound complications with plastic surgery is associated with increased rates of prosthesis retention and limb salvage.
Total hip arthroplasty (THA) is effective, reproducible, and durable in the treatment of hip joint arthritis. While improvements in polyethylene materials have significantly reduced wear rates and osteolysis, aseptic loosening of implants remains one of the leading causes of revision THA. Additionally, fears of dislocation and instability have driven the increase in the utilization of larger diameter femoral heads in primary THA which can lead to increased wear when coupled with a polyethylene articulation. Finally, the increasing number of younger and active patients undergoing THA raises questions with regards to the ability of modern conventional bearings to provide durability and longevity beyond second and third decades following joint implantation. Ceramic-on-ceramic articulations are ideally suited for today's young and high demand patients undergoing primary THA. It has the lowest in-vitro wear properties of any bearing couple and the wear characteristics are further improved by its wettability and lubrication particularly when larger heads are utilised. Additionally, improvements in material properties and prosthesis design have significantly decreased fracture rates and increased the reliability of these implants. Furthermore, reported outcomes and longevity of modern ceramic-on-ceramic THAs in younger patients have all shown excellent survivorship despite patients achieving and maintaining a very high level of activity and function. In short, it is the bearing couple most in tune with current market demands and utilization trends. While registry data and meta-analyses of published literature have failed to show the superiority of ceramic-on-ceramic articulations compared to conventional bearings at 10 years, there is evidence that even highly crosslinked polyethylene (HXPE) is not immune to wear. Selvarajah et al. reported steady, in-vivo wear rates of HXPE exceeding 0.1mm/year threshold in young THA patients with 36mm ceramic ball heads. Additionally, small osteolytic lesions have been observed in hips with HXPE bearings at 12–14 years follow up. Finally, analysis of all controlled randomised studies have shown less osteolysis of ceramic-on-ceramic hips compared to polyethylene articulations. The significance of these lesions are unclear but the question remains: Can HXPE as a bearing be able to provide over 30 years of service needed to outlast patients younger than 60 years? Concerns with cost, squeaking, and fractures do not make ceramic-on-ceramic bearings suitable for all patients undergoing primary THA. However, in young, healthy and active patients, a modern ceramic- on-ceramic articulation is most likely to provide the lowest wear rates, lowest risk of osteolysis, and greatest chance for life-long durability.
Expanded indications and patient demand have significantly increased the number of TKA performed in young and active patients under age 55. While improved materials have decreased the likelihood of early catastrophic wear, concerns remain with the performance and survivorship of TKA implants in this patient population. Therefore, the purpose this study is to evaluate the clinical outcomes, complications, and implant survivorship of TKAs performed in patients under age 55. We retrospectively reviewed 1194 primary TKA performed for the diagnosis of primary knee osteoarthritis performed at our institution between 2013–2016. There were 291 TKA performed in patients under age 55. Patients were excluded if they had 1) prior history of fracture, 2) renal disease, 3) inflammatory joint disease, and 4) required therapeutic anticoagulation. The primary outcome of interest was rate of revision at 30 days, 1, 2, and 5-year time points. Secondary outcomes included postoperative transfusion rate, calculated blood loss, length of stay(LOS), rate of DVT/PE, readmission and reoperation.Introduction
Materials and Methods
Total hip arthroplasty (THA) is gaining popularity as a treatment for displaced femoral neck fractures (FNF), especially in physiologically younger patients. While elective THA for primary osteoarthritis (OA) has demonstrated low rates of complications and readmissions, the outcomes of THA for FNF are less predictable. Additionally, these THA procedures are equally included in various alternative payment bundles. Therefore, the aim of this study is to assess postoperative complication rates after THA for primary OA compared with FNF. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2008 to 2016 was queried. Patients were identified using the Current Procedural Terminology (CPT) code for THA (27130) and divided into groups by diagnosis; OA in one group and FNF in another. Univariate statistics were performed. T-test compared continuous variables between groups, and Chi-square test compared categorical variables. Multivariate and propensity matched logistic regression analyses were performed to control for risk factors of interest. The primary outcomes for this study were death or serious morbidity (surgical site infection (SSI), infection, respiratory complication, cardiac complication, sepsis, or blood loss anemia requiring postoperative transfusion). Additional secondary outcomes included the incidence of specific complications, total operative time (time from incision to closure), length of hospital stay and proportion of patients that were discharged home.Introduction
Methods
The aim of this study was to compare the results of 16S/28S rRNA sequencing with the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, and synovial fluid analysis in the diagnosis of prosthetic joint infection (PJI). Between September 2015 and August 2016, 214 consecutive patients were enrolled. In the study population, there were 25 patients with a PJI and 189 controls. Of the PJI patients, 14 (56%) were women, and the mean age at the time of diagnosis was 65 years (38 to 83). The ESR and CRP levels were measured, and synovial fluid specimens were collected prospectively. Synovial fluid was subjected to reverse transcription polymerase chain reaction (RT-PCR)/sequence analysis targeting the 16S/28S rRNA, and to conventional culture. Laboratory personnel who were blind to the clinical information performed all tests. The diagnosis of PJI was based on the criteria of the Musculoskeletal Infection Society.Aims
Patients and Methods
Total hip arthroplasty (THA) is reliable and reproducible in relieving pain and improving function in patients with end-stage arthritis of the hip joint. With improvements in surgical technique and advances in implant and instrument design, there has been a shift in focus from the technical aspects of the surgical procedure to improving the overall patient experience. In addition, shifts in medico-economic trends placed a premium on early patient mobilization, early discharge, and maximizing patient satisfaction. Arguably, a single most important advance in arthroplasty over the past 2 decades has been the development of multimodal pain protocols that form the foundation of many of the rapid recovery protocols today. The principal concept of multimodal analgesia is pain reduction through the utilization of multiple agents that synergistically act at various nodes of the pain pathway, thus, minimizing patient exposure to each individual agent and opioids in order to prevent opioid related adverse events (ORAE). Regional anesthesia has been shown to reduce post-operative pain, morphine consumption, and nausea and vomiting compared to general anesthesia but not length of stay. Additionally, general anesthesia has been shown to be associated with increased rates of post-operative adverse events, The use of peripheral nerve blocks in the form of sciatic, femoral or fascia iliaca blocks have not been shown to significantly reduce post-operative pain compared to controls. Periarticular infiltration of local anesthetics has been shown in some settings to reduce pain during the immediate post-operative period (<24 h). However, no significant differences were noted in terms of early recovery or complications. The use of liposomal bupivacaine (LB) local infiltration decreased pain and shortened length of stay comparable to patients receiving a fascia iliaca compartment block, and has been shown in relatively few randomised trials to provide improved pain relief at 24 hours only compared to conventional bupivacaine. Continuous intra-articular infusion of bupivacaine after THA did not significantly further reduce post-operative pain compared to placebo. In summary, the use of regional anesthesia when appropriate along with local anesthetic infiltration in the setting of a robust multimodal pain protocol minimises pain and complications while maximizing patient satisfaction following THA.
Infection following total knee arthroplasty (TKA) can cause significant morbidity to the patient and be associated with significant costs and burdens to the health care system. Wound complications often initiate the cascade that can eventually lead to deep infection and implant failure. Galat et al. reported that wound complications following TKA requiring surgical treatment were associated with a 2-year cumulative risk of major reoperation and deep infection of 5.3% and 6.0%, respectively. Consequently, developing a systematic approach to the management of wound problems following TKA can potentially minimise subsequent complications. Unlike the hip, the vascular supply to the soft tissue envelope to the knee is less robust and more sensitive to the trauma of surgery. Therefore, proper soft tissue handling and wound closure at the time of surgery can minimise potential wound drainage and breakdown post-operatively. Kim et al. showed, using a meta-analysis of the literature, that primary skin closure with staples demonstrated lower wound complications, decreased closure times, and lower resource utilization compared to sutures. However, a running subcuticular closure enables the most robust skin perfusion following TKA. Finally, the use of hydrofiber surgical dressings following surgery was associated with increased patient comfort and satisfaction and reduced the incidence of superficial surgical site infection. A wound complication following TKA needs to be managed systematically and aggressively. A determination of whether the extent of the involvement is superficial or deep is critical. Antibiotics should not be started without first excluding the possibility of a deep infection. Weiss and Krackow recommended return to the operating room for wound drainage persisting beyond 7 days. While incisional negative pressure wound therapy can occasionally salvage the “at risk” draining wound following TKA, its utilization should be limited only to the time immediately following surgery and should not delay formal surgical debridement, if indicated. Finally, early wound flap coverage and co-management of wound complications with plastics surgery is associated with increased rates of prosthesis retention and limb salvage.
To evaluate the effectiveness of an institutionally developed
algorithm for evaluation and diagnosis of prosthetic joint injection
and to determine the impact of this protocol on overall hospital
re-admissions.p We retrospectively evaluated 2685 total hip arthroplasty (THA)
and total knee arthroplasty (TKA) patients prior to (1263) and following
(1422) the introduction of an infection detection protocol. The
protocol used conservative thresholds for C-reactive protein to
direct the medical attendant to aspirate the joint. The protocol
incorporated a clear set of laboratory and clinical criteria that
allowed a patient to be discharged home if all were met. Patients were
included if they presented to our emergency department within 120
days post-operatively with concerns for swelling, pain or infection
and were excluded if they had an unambiguous infection or if their
chief complaint was non-orthopaedic in nature.Aims
Patients and Methods
Total knee arthroplasty (TKA) is reliable, durable, and reproducible in relieving pain and improving function in patients with arthritis of the knee joint. Cemented fixation is the gold standard with low rates of loosening and excellent survivorship in several large clinical series and joint registries. While cementless knee designs have been available for the past 3 decades, changing patient demographics (i.e. younger patients), improved implant designs and materials, and a shift towards TKA procedures being performed in ambulatory surgery centers has rekindled the debate of the role of cementless knee implants in TKA. The drive towards achieving biologic implant fixation in TKA is also driven by the successful transition from cemented hip implants to uncemented THA. However, new technologies and new techniques must be adopted as a result of an unmet need, significant improvement, and/or clinical advantage. Thus, the questions remain: 1) Why switch; and 2) Is cementless TKA more reliable, durable, or reproducible compared to cemented TKA? There are several advantages to using cement during TKA. First, the technique can be universally applied to all cases without exception and without concerns for bone health or structure. Second, cement can mask imprecisions in bone cuts and is a remarkably durable grout. Third, cement allows for antibiotic delivery at the time surrounding surgery which has been shown in some instances to reduce the risk of subsequent infection. Finally, cement fixation has provided successful and durable fixation across various types knee designs, surface finishes, and articulations. On the other hand, cementless knee implants have had an inconsistent track record throughout history. While some have fared very well, others have exhibited early failures and high revision rates. Behery et al. reported on a series of 70 consecutive cases of cementless TKA matched with 70 cemented TKA cases based on implant design and demographics and found that cementless TKA was associated with a greater risk of aseptic loosening and revision surgery at 5 years follow up. Finally, to date, there has not been a randomised controlled clinical trial demonstrating superiority of cementless fixation compared to cemented fixation in TKA. Improvements in materials and designs have definitely made cementless TKA designs viable. However, concerns with added cost, reproducibility, and durability remain. Cement fixation has withstood the test of time and is not the main cause of TKA failure. Therefore, until there is significant data showing that cementless TKA is more durable, reliable, and reproducible compared to cemented TKA, the widespread use of these implants cannot be recommended.
Improvements in ceramic materials, component design, and surgical technique have made ceramic bearing complications increasingly rare. However, when it happens, a fractured ceramic component can cause significant pain and morbidity following total hip arthroplasty (THA). The hard and sharp particulate debris from fractured ceramic components can cause damage to the existing hip prosthesis and jeopardise subsequent revision THA results due to third body wear. Patients with ceramic fractures can present with sudden onset of pain and dysfunction. Often, the patient will report a noisy hip articulation. Radiographs can range from subtle densities surrounding the hip implant to complete disintegration and loss of sphericity of the femoral head or acetabular liner. Ceramic component fractures should be treated expeditiously. Revision options for failed ceramic components depend on existing component fixation, position, and locking mechanism and femoral trunnion integrity. In order to retain the implants, the components must be well-fixed, in good position, and have tapers and locking mechanisms that can accept new modular components. Additionally, an extensile exposure and complete synovectomy are necessary to remove as much of the sharp particulate debris. Finally, a new ceramic ball head with a titanium inner sleeve should be used in revisions for fractured ceramics due to their hardness and scratch resistance. Early results for revision surgery for fractured ceramic components were inconsistent. Allain et al. reported on a series of 105 revisions performed for ceramic head fractures and found that the survivorship at 5 years was only 63%. The authors reported a high reoperation rate and also worse survivorship when the acetabular component was retained, a metal head was used for revisions, age younger than 50 years, and when a complete synovectomy was not performed at the time of revision. More recently, Sharma and colleagues reported on a series of 8 ceramic fractures revised to a metal-on-polyethylene articulation performed with a complete synovectomy. At 10-year follow-up, the authors reported on failures; increased wear; or lesser function compared to 6 matched patients undergoing revision using similar implants for other diagnoses. Others have also reported catastrophic failures when revising fractured ceramic components using metal ball heads. In summary, ceramic bearing complications in THA are rare but catastrophic events. A systematic approach to evaluation and management is necessary to ensure a safe return.
Total hip arthroplasty (THA) is effective, reproducible, and durable in the treatment of hip joint arthritis. While improvements in polyethylene materials have significantly reduced wear rates and osteolysis, aseptic loosening of implants remains one of the leading causes of revision THA. Additionally, fears of dislocation and instability have driven the increase in the utilization of larger diameter femoral heads in primary THA which can lead to increased wear when coupled with a polyethylene articulation. Finally, the increasing number of younger and active patients undergoing THA raises questions with regards to the ability of modern conventional bearings to provide durability and longevity beyond second and third decades following joint implantation. Ceramic-on-ceramic articulations are ideally suited for today's young and high demand patients undergoing primary THA. It has the lowest in-vitro wear properties of any bearing couple and the wear characteristics further improved by its wettability and lubrication particularly when larger heads are utilised. Additionally, improvements in material properties and prosthesis design have significantly decreased fracture rates and increased the reliability of these implants. Furthermore, reported outcomes and longevity of modern ceramic-on-ceramic THAs in younger patients have all shown excellent survivorship despite patients achieving and maintaining a very high level of activity and function. In short, it is the bearing couple most in tune with current market demands and utilization trends. While registry data and meta-analyses of published literature have failed to show the superiority of ceramic-on-ceramic articulations compared to conventional bearings at 10 years, there is evidence that even highly crosslinked polyethylene (HXPE) is not immune to wear. Selvarajah et al. reported steady, in-vivo wear rates of HXPE exceeding 0.1 mm/year threshold in young THA patients with 36 mm ceramic ball heads. Additionally, small osteolytic lesions have been observed in hips with HXPE bearings at 12–14 years follow up. Finally, analysis of all controlled randomised studies have shown less osteolysis of ceramic-on-ceramic hips compared to polyethylene articulations. The significance of these lesions are unclear but the question remains: Can HXPE as a bearing be able to provide over 30 years of service needed to outlast patients younger than 60 years? Concerns with cost, squeaking, and fractures do not make ceramic-on-ceramic bearings suitable for all patients undergoing primary THA. However, in young, healthy and active patients, a modern ceramic-on-ceramic articulation is most likely to provide the lowest wear rates, lowest risk of osteolysis, and greatest chance for life-long durability.
Infection following primary total knee arthroplasty (TKA) is fortunately a relatively uncommon complication with an incidence of approximately 1%. However, because the morbidity and cost of treatment of deep prosthetic TKA infections is so high, effective prevention strategies are key quality improvement initiatives. The cause of post-operative infections are multifactorial and complex but can generally be categorised into 1) host, 2) surgical, and 3) environmental factors. The purpose of this abstract to provide an outline of these factors and their influences on the infection risk following TKA. Patient factors and optimization of modifiable risk factors have been shown to decrease the risk for infection. While the individual contributions of factors such as body mass index (BMI), diabetes, nutritional status, Charlson Comorbidity Index (CCI), and renal disease are unknown, together, they have been shown to influence infection risk. Additionally, Tayton et al. analyzed 64,566 primary TKAs in the New Zealand Joint Registry and found that male gender and prior knee surgery were also independent risk factors of development of PJI 12 months following TKA. Finally, Crowe and colleagues also identified tobacco use and Staphylococcus aureus colonization as modifiable risk factors for minimizing PJI following primary TKA. Timely administration of prophylactic antibiotics prior and after surgery has been shown to be the most effective strategy to reduce infection risk. The optimal prophylaxis regimen for all patients is unknown and in certain situations, administration of Vancomycin in additional to a conventional cephalosporin may be beneficial. However, universal administration of Vancomycin has not been shown to decrease the incidence of surgical site infections and could actually increase the risk for renal failure. Conversely, addition of antibiotics to cement during primary TKA has not been shown to reduce long term infection risk. The use of dilute betadine lavage has been shown by some authors to be beneficial. Finally, good surgical technique, proper soft tissue handling, and meticulous wound closure are all critical factors influencing the risk for infectious complications following TKA. Environmental factors have also been shown to affect infection rates following TKA. While the use of laminar flow and body exhaust suits have not been shown to significantly influence the risk for infection, minimizing operating room traffic has been shown effective in reducing the risk for contamination. Some authors have shown ultraviolet light systems to decrease airborne contaminants. In summary, factors influencing infection risk following TKA are complex and multifactorial. Patient selection, optimization of modifiable risk factors, appropriate use of antibiotics, and minimization of OR traffic are among the most common strategies to minimizing infection.
Failure resulting from a recurrent infection in total knee arthroplasty (TKA) is a challenging problem. Knee arthrodesis is one treatment option, however fusion is not always successful, as there is huge bone defect. The authors reports a new arthrodesis technique that uses a bundle of flexible intramedullary rods and an antibiotic-loaded cement spacer. There were 13 cases of arthrodesis due to recurrent periprosthetic joint infection, which were performed by the first author (WS Cho) at Asan Medical Center in Seoul from 2005 to 2014. All previous prosthetic components were removed and cement was thoroughly excised using a small osteotome. Two stage operation was done in most of cases. After thorough debridement, antibiotics loaded cement was inserted in first stage, flexible intramedullary rods were inserted retrogradely in the femoral side with the knee in flexion under fluoroscopy guidance. After filling the femoral intramedullary canal, the rods were then driven back securely into the tibial medullary canal. We aimed for as much rod length as possible to maximize stability. After 6 weeks of first stage operation, the rods of the femoral and tibial sides were arranged such that they overlapped and interdigitated to maximize mechanical strength, maintain the limb length and keep the rotational alignment. The interdigitating rod ends were tightly fixed using two (or three) cerclage wires. Antibiotic-loaded cement was filled into the knee joint space so that the cement is fit to the irregular contour of the femur and tibia, which was resulted from the severe bone loss. Postoperatively, patients were allowed to weight bear as tolerated.Purpose
Methods
The utilization of ceramic components in Total Hip Arthroplasty has experienced an expanded acceptance by the orthopedic community. This increased acceptance has been largely due to the lower risk of fracture due to the introduction of zirconia toughened alumina ceramics. This extra-high strength ceramic composite has been proven clinically over the past 13 years and found to be much more reliable than previous ceramic materials. The goal is to verify this finding by published registry data as well as clinical outcome. Registry data on fractured ceramic components have been compared with the data received from the largest manufacturer of ceramic hip components. Additionally, the clinical outcome of ceramic on ceramic artificial hips has been evaluated.Introduction
Methods
Post-traumatic avascular necrosis of the femoral head usually occurs after hip dislocation and femoral neck fracture. Recently along the development of hip arthroscopy, early stage of avascular necrosis of the femoral head can be treated rthroscopically. We hereby present two cases of post-traumatic avascular necrosis patients treated with hip arthroscopy. Case 1 Twenty one year old female patient came to the hospital because of fall from height of 3 floors. Left acetabular fracture, both superior pubic rami fractures and severely displaced left femoral neck fracture were identified at the emergency department (Fig. 1-A). She underwent surgery at the injury day. After the repair of ruptured urinary bladder, internal fixation of the femoral neck was done. Four cannulated screws with washers were inserted for displaced femoral neck fracture, consistent with garden stage IV (Fig. 1-B). Skeletal traction of ipsilateral lower extremity was applied four weeks after the surgery for acetabular fracture. She visited us for painful limitation of motion on left hip at eight months postoperatively. Plain radiograph showed collapse of femoral head and osteophyte formation which were caused by post-traumatic avascular necrosis (Fig. 1-C,D). Femoral head was perforated by a screw. She was planned to remove the screw and resect the osteophyte arthroscopically. On arthroscopic examination, severe synovitis and folded, collapsed femoral cartilage were identified (Fig. 1-E). Screws were removed and osteophyte were also resected (Fig. 1-F). We filled the cavity caused by the screws with allogenic strut graft for structural support. After the surgery, pain was relieved and she came back to her active daily living and for six months, no other complication nor further collapse were identified postoperatively. Case 2 Fourty year old male patient was admitted to the hospital for fall from height about fifteen feet from the ground. Left femoral neck fracture was identified on the emergency department. Previously he had underwent intramedullary nailing for the femoral shaft fracture about five years ago. Urgent internal fixation with four cannulated screws was done on the day of injury. The fixation was unsatisfactory because previously inserted intramedullary nail hindered the proper trajectory of screws. Furthermore, direction of cephalad interlocking holes of the nail were not consistent with the anteversion of femoral neck, we could not place the screws through the nail. Four months after the index surgery, collapse of femoral head and loosening of screws have occurred. MRI showed the collapse of femoral head and posttraumatic avascular necrosis. Prominent bony beak of femoral neck were identified and he complained difficulty and pain on his hip during abduction. We left two screws for secure fixation and resected the bony beak using arthroscopic burr. After the surgery, he felt free from the pain on abduction of hip. Even though collapse of the femoral head is identified, early intervention by the arthroscopy could minimize pain or delay the progression of arthritic change. Authors think that it might be helpful for the young adult patients in terms of pain relief and potential delay of the total hip arthroplasty.Discussion
During revision surgery with a well-fixed stem, a titanium sleeve can be used in conjunction with a ceramic head to achieve better stress distribution across the taper surface. Previous studies have observed that the use of a ceramic head can mitigate the extent of corrosion damage at the taper. Moreover, Thirty sleeved ceramic heads (Biolox Option: CeramTec) were collected during revision surgery as part of a multi-center retrieval program. The sleeves were used in conjunction with a zirconia-toughened alumina femoral head. The femoral heads and sleeves were implanted between 0.0 and 3.25 years (0.8±0.9, Figure 1). The implants were revised predominantly for instability (n=14), infection (n=7), and loosening (n=5). Fifty percent of the retrievals were implanted during a primary surgery, while 50% had a history of a prior revision surgery. Fretting corrosion was scored using a previously described 4-point, semi-quantitative scoring system proposed by Higgs [2].Introduction
Materials and Methods
Ceramic bearing complications are rare, but can be a catastrophic complication following total hip arthroplasty (THA). Particulate debris from fractured ceramics can cause damage to the hip prosthesis and jeopardise subsequent revision THA. Patients with ceramic fractures can present with sudden onset of pain and dysfunction. Often, the patient will report a noisy hip articulation. Radiographs can range from subtle densities surrounding the hip implant to complete disintegration and loss of sphericity of the femoral head or acetabular liner. Ceramic component fractures should be treated expeditiously. Revision options for failed ceramic components depend on existing component fixation, position, and type. In order to retain the implants, the components must be well fixed, appropriately positioned, and have tapers that are undamaged and can accept current femoral heads. Additionally, an extensile exposure and complete synovectomy are necessary to remove the sharp ceramic particulate debris. Finally, a ceramic ball head should be used to revise a fractured ceramic THA. Newer, alumina composite ceramic ball heads are harder, reliable, and more scratch resistant compared to metal ball heads. However, when retaining the femoral component, a ceramic ball head with a titanium sleeve should be used to prevent subsequent failures. In summary, ceramic bearing complications are rare but catastrophic events. A systematic approach to evaluation and management is necessary to ensure a safe return.
Revision total knee arthroplasty (TKA) can pose significant challenges. Successful reconstruction requires a systematic approach with the ultimate goal being a well fixed and balanced knee prosthesis. Careful preoperative planning is necessary for safe exposure, component removal, and appropriate management of bone loss during revision knee surgery. Prior to surgery, the cause of failure must be understood. Revision TKA without a clear diagnosis has been shown to lead to predictable poor results. A careful history and physical examination for both intrinsic and extrinsic causes of knee pain need to be performed. An ESR and C-reactive protein should be obtained in every patient with a painful TKA and in cases of serologic abnormalities, a joint aspiration performed. The integrity of the collateral ligaments and the degree of anticipated bone loss at the time of revision needs to be established. In cases of severe collateral ligament deficiency, the need for constrained or hinged knee implants should be anticipated. Plain radiographs are needed to evaluate present component position, loosening, and osteolysis. Oblique radiographs and advanced imaging (i.e. CT or MRI) have been shown to more accurately quantify the severity of lysis compared to standard radiographs. This careful assessment can help prepare for the need of special implants, stems, wedges, or augments. Finally, patient risk stratification and medical co-management can help minimise complications following revision TKA. Optimization of potentially modifiable risk factors such as glycemic control, BMI, and preoperative hemoglobin can reduce perioperative morbidity and complications.
While total hip arthroplasty (THA) has been shown successful at relieving pain and improving function in patients with coxarthrosis, wear and instability remain leading causes for revision surgery. Highly crosslinked polyethylene (HXPE) has significantly reduced wear and osteolysis but volumetric wear associated with the use of larger diameter ball heads may be an issue in the long-term. Finally, concerns with femoral taper corrosion have increased the utilization of ceramic ball heads in recent years. Ceramic on ceramic articulations are optimised for both minimizing implant wear and instability. It is biocompatible, wettable, and possesses the lowest in vitro and in vivo wear rates among all bearing couples. In fact, wear rates are lowest when the ceramic ball head size is maximised. Additionally, modern ceramic on ceramic THA designs have had an excellent clinical track record with low rates of loosening, failure, and no reports of osteolysis in even highly active, young patients. Concerns with ceramics center around issues related to fracture risk, squeaking, and cost. While the phenomenon of squeaking remains poorly understood, the reliability of ceramic implants have steadily improved with better materials, design, and manufacturing. The fracture risk for modern pure alumina implants and the newer alumina matrix composite ceramics are 1 in 5000 and 1 in 100,000, respectively. The advantages of ceramic on ceramic THAs will not be realised on every patient and therefore, should be selectively used. However, with expected increases in life expectancy and more young, active patients undergoing THA, ceramic on ceramic THA should be strongly considered in patients under age 60 years.
Infection following primary total knee arthroplasty (TKA) is fortunately a relatively uncommon complication with an incidence of approximately 1%. However, because the morbidity and cost of treatment of deep prosthetic TKA infections is so high, effective prevention strategies are key quality improvement initiatives. The cause of post-operative infections are multifactorial and complex but can generally be categorised into 1) host, 2) surgical, and 3) environmental factors. The purpose of this abstract is to provide an outline of these factors and their influences on the infection risk following TKA. Patient factors and optimization of modifiable risk factors have been shown to decrease the risk for infection. While the individual contributions of factors such as body mass index (BMI), diabetes, nutritional status, Charlson Comorbidity Index (CCI), and renal disease are unknown, together, they have been shown to influence infection risk. Additionally, Tayton et al. analyzed 64,566 primary TKAs in the New Zealand Joint Registry and found that male gender and prior knee surgery were also independent risk factors of development of PJI 12 months following TKA. Finally, Crowe and colleagues also identified tobacco use and Staphylococcus aureus colonization as modifiable risk factors for minimizing PJI following primary TKA. Timely administration of prophylactic antibiotics prior and after surgery has been shown to be the most effective strategy to reduce infection risk. The optimal prophylaxis regimen for all patients is unknown and in certain situations, administration of Vancomycin in additional to a conventional cephalosporin may be beneficial. However, universal administration of Vancomycin has not been shown to decrease the incidence of surgical site infections and could actually increase the risk for renal failure. Conversely, addition of antibiotics to cement during primary TKA has not been shown to reduce long term infection risk. The use of dilute betadine lavage has been shown by some authors to be beneficial. Finally, good surgical technique, proper soft tissue handling, and meticulous wound closure are all critical factors influencing the risk for infectious complications following TKA. Environmental factors have also been shown to affect infection rates following TKA. While the use of laminar flow and body exhaust suits have not been shown to significantly influence the risk for infection, minimizing operating room traffic has been shown effective in reducing the risk for contamination. Some authors have shown ultraviolet light systems to decrease airborne contaminants. In summary, factors influencing infection risk following TKA are complex and multifactorial. Patient selection, optimization of modifiable risk factors, appropriate use of antibiotics, and minimization of OR traffic are among the most common strategies to minimizing infection.
Ceramic bearing complications are rare but can cause significant pain and morbidity following total hip arthroplasty (THA). The hard and sharp particulate debris from fractured ceramic components can cause damage to the existing hip prosthesis and jeopardise subsequent revision THA results due to third body wear. Patients with ceramic fractures can present with sudden onset of pain and dysfunction. Often, the patient will report a noisy hip articulation. Radiographs can range from subtle densities surrounding the hip implant to complete disintegration and loss of sphericity of the femoral head or acetabular liner. Ceramic component fractures should be treated expeditiously. Revision options for failed ceramic components depend on existing component fixation, position, and locking mechanism and femoral trunnion integrity. In order to retain the implants, the components must be well-fixed, in good position, and have tapers and locking mechanisms that can accept new modular components. Additionally, an extensile exposure and complete synovectomy are necessary to remove the sharp particulate debris. Finally, a new ceramic ball head with a titanium inner sleeve should be used in revisions for fractured ceramics due to their hardness and scratch resistance. Early results for revision surgery for fractured ceramic components were inconsistent. Allain et al. reported on a series of 105 revisions performed for ceramic head fractures and found that the survivorship at 5 years was only 63%. The authors reported a high reoperation rate and also worse survivorship when the acetabular component was retained, a metal head was used for revisions, age younger than 50 years, and when a complete synovectomy was not performed at the time of revision. More recently, Sharma and colleagues reported on a series of 8 ceramic fractures revised to a metal-on-polyethylene articulation performed with a complete synovectomy. At 10-year follow up, the authors reported on failures; increased wear; or lesser function compared to 6 matched patients undergoing revision using similar implants for other diagnoses. Others have also reported catastrophic failures when revising fractured ceramic components using metal ball heads. In summary, ceramic bearing complications in THA are rare but catastrophic events. A systematic approach to evaluation and management is necessary to ensure a safe return.
There are still some controversies over the routine use of negative suction drainage after primary total hip arthroplasty (THA). In this study we are to know the benefits of new suction drainage management strategy after primary THA. From 2010 to 2012, two hundred patients who had unilateral primary THA were randomly allocated into two groups. One group had negative suction drainage immediately after THA (Group 1). In the other group, the suction drainage was inserted but negative pressure was applied more than 12 hours after surgery, in the morning postoperative day one (Group 2). All surgeries were performed by one single hip surgeon using the same technique and postoperative rehabilitation protocol was all same. We checked the amount of blood loss, changes in hemoglobin (Hb), volume of blood transfusion, superficial or deep wound infection and hematoma. Clinical results were evaluated using HHS score.Purpose
Materials and methods
Highly crosslinked polyethylene (HXLPE) was clinically introduced approximately a decade and a half ago to reduce polyethylene wear rates and subsequent osteolysis. Clinical and radiographic studies have repeatedly shown increased wear resistance, however concerns of rim oxidation and fatigue fracture remain. Although short to intermediate term retrieval studies of these materials are available, the long-term behavior of these materials remains unclear. Between 2000 and 2015, 115 1st generation HXLPE acetabular liners implanted for 5 or more years were collected and analyzed as part of an ongoing, multi-institutional orthopaedic implant retrieval program. There were two material cohorts based on thermal processing (annealed (n=45) and remelted (n=70)). Each cohort was stratified into two more cohorts based on implantation time (5 – 10 years and >10 years). For annealed components, the intermediate-term liners (n=30) were implanted on average (±SD) for 7.3 ± 1.7 years while the long-term liners (n=15) were implanted for 11.3 ± 1.8 years. For remelted components, the intermediate-term liners (n=59) were implanted on average (±SD) for 7.2 ± 1.3 years while the long-term liners (n=11) were implanted for 11.3 ± 1.2 years. For each cohort, the predominant revision reasons were loosening, instability, and infection (Figure 1). Short-term liners (in-vivo <5ys) from previous studies were analyzed using the same protocol for use as a reference. For oxidation analysis, thin slices (∼200 μm) were taken from the superior/inferior axis and subsequently boiled in heptane for 6 hours to remove absorbed lipids that may interfere with the oxidation analysis. 3mm line profiles (in 100μm increments) were taken perpendicular to the surface at each region of interest. Oxidation indices were calculated according to ASTM 2102. Penetration was measured directly using a calibrated micrometer (accuracy=0.001mm).Introduction
Methods
Total hip arthroplasty (THA) is the most common surgery performed for complications of bipolar arthroplasty. The present study evaluated the functional results and complications associated with this surgery. Forty eight hips (48 patients) who had conversion of bipolar arthroplasty to THA between 1998 June and 2013 June, and who were followed-up for more than one year were evaluated. Twenty one hips had conversion surgery to THA using a Fitmore cup with metal-on-metal articulation (28 mm head). Six hips had surgery using the SecurFit cup and three hips, using the Lima LTO cup with ceramic-on-ceramic articulation (28 mm or 32 mm head). Eighteen hips had surgery using a large head metal-on-metal bearing: –MMC (seven hips), ACCIS (six hips) and Magnum (five hips). The average time of follow-up duration was 3.9 years (range, 1.0–11.3). There were 22 men and 26 women between the ages of 28 and 80 years (average, 68.9 years) at the time of conversion surgery. Conversion arthroplasty was performed for acetabular erosion without femoral stem loosening in 19 hips, acetabular cartilage erosion with femoral stem loosening in 13 hips, periprosthetic fracture in 12 hips, and recurrent dislocation in four hips. Results were evaluated using Harris hip score (HHS) and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) score. The radiographs were analyzed for evidence of acetabular and femoral osteolysis or loosening. The complications were evaluated.Introduction
Patients and Methods
Previous studies of retrieved CoCr alloy femoral heads have identified imprinting of the stem taper surface features onto the interior head bore, leading researchers to hypothesize that stem taper microgrooves may influence taper corrosion. However, little is known about the role of stem taper surface morphology on the magnitude of in vivo corrosion damage. We designed a matched cohort retrieval study to examine this issue. From a multi-institutional retrieval collection of over 3,000 THAs, 120 femoral head-stem pairs were analyzed for evidence of fretting and corrosion using a visual scoring technique based on the severity and extent of fretting and corrosion damage observed at the taper. A matched cohort design was used in which 60 CoCr head-stem pairs with a smooth stem taper were matched with 60 CoCr head-stem pairs having a micro-grooved surface, based on implantation time, flexural rigidity, apparent length of taper engagement, and head size. This study was adequately powered to detect a difference of 0.5 in corrosion scores between the two cohorts, with a power of 82% and 95% confidence. Both cohorts included CoCr and Ti-6-4 alloy femoral stems. A high precision roundness machine (Talyrond 585, Taylor Hobson, UK) was used to measure surface morphology and categorize the stem tapers into smooth vs. micro-grooved categories. Fretting and corrosion damage at the head/neck junction was characterized using a modified semi-quantitative adapted from the Goldberg method by three independent observers. This method separated corrosion damage into four visually determined categories: minimal, mild, moderate and severe damage.Introduction
Methods
In THA, fretting corrosion at the head-stem taper junction has emerged as a clinical concern that may result in adverse local tissue reactions, even in patients with a metal-on-polyethylene bearing [1]. Taper junctions that employ a ceramic head have demonstrated reduced corrosion at the interface [2]. However, during revision surgery with a well-fixed stem, a titanium sleeve is used in conjunction with a ceramic head to ensure proper fit of the head onto the stem and better stress distribution. In vitro testing has suggested that corrosion is not a concern in sleeved ceramic heads [3]; however, little is known about the in vivo fretting corrosion of the sleeves. The purpose of this study was to investigate fretting corrosion in sleeved ceramic heads. Between 2001 and 2014, 35 sleeved ceramic heads were collected during revision surgery as part of a multi-center retrieval program. The sleeves were all fabricated from titanium alloy and manufactured by 4 companies (CeramTec (n=14), Smith & Nephew (Richards, n=11), Stryker (n=5), and Zimmer (n=5)). The femoral heads were made from 3 ceramics (Alumina (n=7), Zirconia (n=11), and Zirconia-toughened Alumina (n=17)). Sleeve dimensions (length and thickness) were measured using calibrated calipers. Fretting corrosion of the sleeves and available associated stems was scored using a 4-point, semi-quantitative scoring system [4], with 1 being little-to-no damage, and 4 corresponded to severe fretting corrosion. Five sleeves could not be extracted; thus the external surface was not scored.Introduction
Materials and Methods
Patient specific instrumentation (PSI) uses advanced
imaging of the knee (CT or MRI) to generate individualised cutting
blocks aimed to make the procedure of total knee arthroplasty (TKA)
more accurate and efficient. However, in this era of healthcare
cost consciousness, the value of new technologies needs to be critically
evaluated. There have been several comparative studies looking at
PSI Cite this article:
Recent implant design trends have renewed concerns regarding metal wear debris release from modular connections in THA. Previous studies regarding modular head-neck taper corrosion were largely based on cobalt chrome (CoCr) alloy femoral heads. Comparatively little is known about head-neck taper corrosion with ceramic femoral heads or about how taper angle clearance influences taper corrosion. This study addressed the following research questions: 1) Could ceramic heads mitigate electrochemical processes of taper corrosion compared to CoCr heads? 2) Which factors influence stem taper corrosion with ceramic heads? 3) What is the influence of taper angle clearance on taper corrosion in THA? 100 femoral head-stem pairs were analyzed for evidence of fretting and corrosion. A matched cohort design was employed in which 50 ceramic head-stem pairs were matched with 50 CoCr head-stem pairs based on implantation time, lateral offset, stem design and flexural rigidity. Fretting corrosion was assessed using a semi-quantitative scoring scale where a score of 1 was given for little to no damage and a score of 4 was given for severe fretting corrosion. The head and trunnion taper angles were measured using a roundness machine (Talyrond 585, Taylor Hobson, UK). Taper angle clearance is defined as the difference between the head and trunnion taper angles.Introduction
Methods
Ceramic bearing complications are a rare, but can be catastrophic, complication following total hip arthroplasty (THA). Particulate debris from these failed bearings can cause damage the underlying femoral and acetabular components and/or cause further damage to future hip implants. Failure to recognise and appropriately manage these events can lead to significant morbidity. Ceramic component fractures should be treated expeditiously. Delays in diagnosis and treatment can result in destructive damage of the underlying hip prosthesis caused by sharp, abrasive wear of ceramic particles. Patients with ceramic fractures present with sudden onset of pain and dysfunction. Often, the patient will report a noisy hip articulation. Radiographs can range from subtle densities surrounding the hip implant to complete disintegration and loss of sphericity of the femoral head or acetabular liner. As with any other causes of failed joint arthroplasty, a systematic evaluation and workup for failure is mandatory prior to revision surgery. Revision options for failed ceramic components depend on component fixation, position, and type. In order to retain existing implants, the components must be well fixed, appropriately positioned, and have tapers that are undamaged and can accept current femoral heads. If these conditions are not met, then revision of components should be performed to optimise outcomes. Additionally, an extensile exposure is necessary in order to perform a complete synovectomy in order to remove as much of the ceramic particulate debris. Finally, the question of optimal bearing choice following component revision remains an area of debate. Newer, alumina composite ceramic ball heads are harder and more scratch resistant that metal ball heads and therefore preferred in my personal practice. In summary, ceramic bearing complications are rare but catastrophic events. A systematic approach to evaluation and management is necessary to ensure a safe return.
Proposed advantages of patient-specific instrumentation in total knee arthroplasty (TKA) include enhanced accuracy for component positioning, reduced operative time, and increased OR efficiency leading to potential cost savings. However, various studies with relatively small sample sizes have evaluated the impact of these custom cutting guides and were unable to detect any significant differences compared to conventional surgical technique. Therefore, the purpose of this study is to improve the sensitivity of investigation through meta-analysis and compare patient-specific versus standard TKA instrumentation with regard to: (1) coronal alignment, (2) sagittal alignment, (3) operative time, (4) blood loss, (5) transfusion requirement, and (6) peri-operative costs. A systematic review of the peer-reviewed literature indexed on Medline and/or Embase was performed in search of Level I, II, or III studies comparing the results of patient-specific versus standard TKA instrumentation. Nine studies remained following the screening process. The data published in these studies were extracted and aggregated for the purpose of comparing the two treatment groups with regard to coronal alignment, sagittal alignment, operative time, blood loss, transfusion requirement, and peri-operative costs. Using previously published data, it was determined that a sample size of 80 patients per group would have sufficient power (0.80) to detect a significant difference (α = 0.05) in all primary outcomes.Introduction
Methods
Older patients with multiple medical co-morbidities
are increasingly being offered and undergoing total joint arthroplasty
(TJA). These patients are more likely to require intensive care
support, following surgery. We prospectively evaluated the need
for intensive care admission and intervention in a consecutive series
of 738 patients undergoing elective hip and knee arthroplasty procedures.
The mean age was 60.6 years (18 to 91; 440 women, 298 men. Risk
factors, correlating with the need for critical care intervention,
according to published guidelines, were analysed to identify high-risk
patients who would benefit from post-operative critical care monitoring.
A total of 50 patients (6.7%) in our series required critical care
level interventions during their hospital stay. Six independent
multivariate clinical predictors were identified (p <
0.001)
including a history of congestive heart failure (odds ratio (OR)
24.26, 95% confidence interval (CI) 9.51 to 61.91), estimated blood
loss >
1000 mL (OR 17.36, 95% CI 5.36 to 56.19), chronic obstructive
pulmonary disease (13.90, 95% CI 4.78 to 40.36), intra-operative
use of vasopressors (OR 8.10, 95% CI 3.23 to 20.27), revision hip
arthroplasty (OR 2.71, 95% CI 1.04 to 7.04) and body mass index
>
35 kg/m2 (OR 2.70, 95% CI 123 to 5.94). The model was
then validated against an independent, previously published data
set of 1594 consecutive patients. The use of this risk stratification
model can be helpful in predicting which high-risk patients would
benefit from a higher level of monitoring and care after elective
TJA and aid hospitals in allocating precious critical care resources. Cite this article:
Proper restoration of posterior condylar offset during TKA has been shown to be important to maximize range of motion and minimize flexion instability. However, there is little information as to the importance of restoration of mid-sagittal femoral geometry. There is controversy as to whether a TKA prosthesis should have a single radius or multiple radii of curvature. The purpose of this study is to evaluate the effectiveness of a multi-radius femoral component at restoring mid sagittal femoral offset. A consecutive series of 100 TKAs with digital preoperative and postoperative radiographs and standardized radiographic markers were analyzed. There were 71 female and 29 male knees with mean age of 59 years. All TKAs were performed by a single surgeon using a multi-radius femoral component design. The distal femoral resection was set to resect 10 mm from the distal femoral condyle and a posterior referencing system was used to size the femoral component. Using radiographic perfect lateral projections of the knees, a line was drawn along the posterior femoral shaft and another parallel line down the anterior femoral shaft. A 3rd line was then drawn parallel to the posterior shaft at the furthest point posterior on the condyle. A 4th line was drawn parallel to the anterior shaft at the furthest point anterior on the femur. 90 degree angles were constructed to create a grid in the anterior and posterior directions, similar to a previously reported technique. Finally, 45 degree angle lines were created in the grid to assess mid flexion dimensions [Fig-1 and 2]. The percent change in posterior condylar offset (PCO), anterior femoral offset (AFO), mid femoral anterior offset (MAFO) and mid femoral posterior offset (MFPO) were calculated. The mean reproduction of the mid-anterior femoral offset and mid-posterior femoral offset were 101.1% [range 56.5%–167.5%] and 96.8% [range 54.9%–149.0%] of preoperative measurements respectively. The average restoration of posterior offset and anterior offset were 92.8% [range 49.0%–129.8%] and 115.3% of preoperative measurements [range 35.7%–400.0%] respectively. When the posterior condylar offset was restored to within 10% of the native anatomy, the MPFO restoration more closely resembled normal anatomy (103.0% vs. 93.9%, p = 0.005). When the postoperative posterior condylar offset was decreased greater than 20%, both the MAFO (90.1% vs. 104.5%, p = 0.004) and MPFO (78.5% vs. 102.9%, p < 0.001) decreased compared to the native knee. There was no relationship between restoration of the PCO and the MAFO correction (104.6% vs. 99.4%, p = 0.213). Finally, there was no correlation between restoration of anterior femoral offset within 10% of normal and the restoration of mid sagittal femoral offset; 98.0% vs 102.0% for MAFO (p = 0.320) and 98.7% vs 96.3% for MPFO (p = 0.569). A modern multi-radius condylar knee design is capable of reproducing the mid-sagittal geometry of the preoperative knee. However, the restoration of mid sagittal offset is largely dependent on the restoration of the posterior condylar offset. Intraoperative adjustments in anterior and posterior femoral resections can have significant impact in the ability of the implant to reproduce mid-sagittal femoral anatomy.
Infection following total knee arthroplasty (TKA) is a catastrophic complication. In the United States, for chronic, first time infected TKA, the gold standard remains a 2-stage reimplantation (2SR) procedure, with reported success rates approaching 90%. However, there is a lack of consensus on the treatment of subsequent reinfections. The purpose of this study was to use published data on infected TKA to develop a decision tree analysis to determine the treatment method likely to yield the highest quality of life for a patient following a failed 2SR.Introduction
Question
Previous studies regarding modular head-neck taper corrosion were largely based on cobalt chrome (CoCr) alloy femoral heads. Less is known about head-neck taper corrosion with ceramic femoral heads. We asked (1) whether ceramic heads resulted in less taper corrosion than CoCr heads; (2) what device and patient factors influence taper fretting corrosion; and (3) whether the mechanism of taper fretting corrosion in ceramic heads differs from that in CoCr heads.Background:
Questions/purposes:
Sequentially annealed highly crosslinked polyethylenes (HXLPEs) were introduced in total knee replacement (TKR) starting in 2005 to reduce wear and particle-induced osteolysis. Few studies have reported on the clinical performance of HXLPE knees. In this study, we hypothesized that due to the reduced free radicals, sequentially annealed HXLPE would have lower oxidation levels than gamma inert-sterilized controls. 145 tibial components were retrieved at consecutive revision surgeries at 7 different surgical centers. 74 components were identified as sequentially annealed HXLPE (X3, Stryker) while the remainder (n = 71) were conventional gamma inert sterilized polyethylene. The sterilization method was confirmed by tracing the lot numbers by the manufacturer. The conventional inserts were implanted for 1.7 years (Range: 0.0–9.3 years), while the X3 components were implanted 1.1 years (Range: 0.0–4.5 years). Surface damage was assessed using the Hood method. Oxidation analysis was performed in accordance with ASTM 2102 following submersion in boiling heptane for 6 hours to remove absorbed lipids. 30 of the conventional and 29 of the HXLPE inserts were available for oxidation analysis.Introduction
Methods