Any operation induces an elevation in the level of serum C-reactive protein (CRP). After hip and knee arthroplasty the maximal values are seen on the second and third postoperative days, after which the CRP decreases rapidly. There is no difference between patients with cemented or uncemented prostheses. Major postoperative complications may cause a further increase in CRP levels at one and two weeks

Objectives

Effective analgesia after total knee arthroplasty (TKA) improves patient satisfaction, mobility and expedites discharge. This study assessed whether continuous femoral nerve infusion (CFNI) was superior to a single-shot femoral nerve block in primary TKA surgery completed under subarachnoid blockade including morphine.

Aims

The primary aim was to assess the patient-perceived effect of restrictions imposed due to COVID-19 on rehabilitation following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Secondary aims were to assess perceived restrictions, influence on mental health, and functional outcome compared to patients undergoing surgery without restriction.

Introduction

Wear of polyethylene inserts plays an important role in failure of total knee replacement and can be monitored in vivo by measuring the minimum joint space width in anteroposterior radiographs. The objective of this retrospective cross-sectional study was to compare the accuracy and precision of a new model-based method with the conventional method by analysing the difference between the minimum joint space width measurements and the actual thickness of retrieved polyethylene tibial inserts.

We made a prospective study of the incidence of fatal pulmonary embolism in patients after total knee replacement with no prophylactic anticoagulation. There were 499 consecutive patients having 527 knee replacements. They all wore anti-thromboembolic stockings and were mobilised 48 hours after surgery. No patient was lost to follow-up. One patient died of pulmonary embolism 22 days after operation. There were no other deaths within three months of operation. The incidence of fatal pulmonary embolism was 0.19% (95% confidence interval: 0 to 0.6%). Fatal pulmonary embolism is rare after total knee replacement without prophylactic anticoagulation and the routine anticoagulation of these patients is of doubtful value

We report the five- to-ten year results of Anderson Orthopaedic Research Institute type-2 bone defects treated with modular metal augments in revision knee surgery. A total of 102 revision knee arthroplasties in patients with type-2 defects treated with augments and stems were prospectively studied. Seven patients (seven knees) had incomplete follow-up and 15 patients (16 knees) died with the arthroplasty in situ. The mean follow-up of the 79 remaining knees was 7 ± 2 years (5 to 11). The presence of non-progressive radiolucent lines around the augment in 14% of knees was not associated with poorer knee scores, the range of movement, survival of the component or the type of insert which was used (p > 0.05). The survival of the components was 92 ± 0.03% at 11 years (95% CI, 10.3 to 11.2). We recommend the use of modular augmentation devices to treat type-2 defects in revision knee surgery

We have previously reported the short-term radiological results of a randomised controlled trial comparing kinematically aligned total knee replacement (TKR) and mechanically aligned TKR, along with early pain and function scores. In this study we report the two-year clinical results from this trial. A total of 88 patients (88 knees) were randomly allocated to undergo either kinematically aligned TKR using patient-specific guides, or mechanically aligned TKR using conventional instruments. They were analysed on an intention-to-treat basis. The patients and the clinical evaluator were blinded to the method of alignment.

At a minimum of two years, all outcomes were better for the kinematically aligned group, as determined by the mean Oxford knee score (40 (15 to 48) versus 33 (13 to 48); p = 0.005), the mean Western Ontario McMaster Universities Arthritis index (WOMAC) (15 (0 to 63) versus 26 (0 to 73); p = 0.005), mean combined Knee Society score (160 (93 to 200) versus 137 (64 to 200); p= 0.005) and mean flexion of 121° (100 to 150) versus 113° (80 to 130) (p = 0.002). The odds ratio of having a pain-free knee at two years with the kinematically aligned technique (Oxford and WOMAC pain scores) was 3.2 (p = 0.020) and 4.9 (p = 0.001), respectively, compared with the mechanically aligned technique. Patients in the kinematically aligned group walked a mean of 50 feet further in hospital prior to discharge compared with the mechanically aligned group (p = 0.044).

In this study, the use of a kinematic alignment technique performed with patient-specific guides provided better pain relief and restored better function and range of movement than the mechanical alignment technique performed with conventional instruments.

Cite this article: Bone Joint J 2014;96-B:907–13.

We conducted a multicentre cohort study of 228 patients with osteoarthritis followed up after total hip or knee replacement. Quality of life and patient satisfaction were assessed by self-administered questionnaires. Patient satisfaction was the dependent variable in a multivariate linear regression model. Independent variables included sociodemographic factors, pre- and post-operative clinical characteristics and the pre-operative and post-discharge health-related quality of life. The mean age of the patients was 69 years (. sd. 9), and 43.8% were male. Pre- and postoperative clinical characteristics were not associated with satisfaction with health care. Only pre-operative bodily pain (p < 0.01) and pre-operative social functioning (p < 0.05) influenced patient satisfaction with care. The pre-operative health-related quality of life and patient characteristics have little effect on inpatient satisfaction with care. This suggests that the impact of the care process on satisfaction may be independent of observed and perceived initial patient-related characteristics

We studied the changes in plasma viscosity and C-reactive protein to establish normal values after total hip or knee arthroplasty. Viscosity decreased from 1.68 (+/- 0.017) to 1.57 (+/- 0.014) on the first postoperative day and thereafter rose to 1.60 (+/- 0.019), 1.75 (+/- 0.015), and 1.74 (+/- 0.011) on the third, seventh and fourteenth days respectively. Six to eight weeks after operation it had returned to pre-operative levels. A viscosity above the upper limit of the laboratory range, obtained more than two months after operation, may be considered as abnormal. The C-reactive protein level increased significantly on the first postoperative day and then decreased from a peak on the second day, attaining nearly normal levels at six to eight weeks after operation. It may be a more sensitive indicator of deep postoperative infection than plasma viscosity

Aims

Fungal prosthetic joint infections (PJIs) are rare and account for about 1% of total PJIs. Our aim was to present clinical and microbiological results in treating these patients with a two-stage approach and antifungal spacers.

This cohort study investigated the influence of psychological factors, including perception of illness, anxiety and depression on recovery and functional outcome after total knee replacement surgery.

A total of 100 patients (55 male; 45 female) with a mean age of 71 (42 to 92) who underwent a primary total knee replacement for osteoarthritis were recruited into this study. In all 97 participants completed the six week and 87 the one year follow-up questionnaires.

Pre-operatively patients completed the revised Illness Perception Questionnaire, Hospital Anxiety and Depression Scale and Recovery Locus of Control Scale. Function was assessed pre-operatively, at six weeks and one year using Oxford Knee Score (OKS) and the goniometer-measured range of movement (ROM).

The results showed that pre-operative function had the biggest impact on post-operative outcome for ROM and OKS. In addition questionnaire variables and depression had an impact on the OKS at six weeks. Depression and anxiety were also associated with a higher (worse) knee score at one year but did not influence the ROM at either six weeks or one year.

Recovery from total knee replacement can be difficult to predict. This study has identified psychological factors that play an important role in recovery from surgery and functional outcome. These should be taken into account when considering patients for total knee replacement.

Cite this article: Bone Joint J 2014;96-B:210–16.

The optimum cementing technique for the tibial component in cemented primary total knee replacement (TKR) remains controversial. The technique of cementing, the volume of cement and the penetration are largely dependent on the operator, and hence large variations can occur. Clinical, experimental and computational studies have been performed, with conflicting results. Early implant migration is an indication of loosening. Aseptic loosening is the most common cause of failure in primary TKR and is the product of several factors. Sufficient penetration of cement has been shown to increase implant stability.

This review discusses the relevant literature regarding all aspects of the cementing of the tibial component at primary TKR.

Cite this article: Bone Joint J 2013;95-B:295–300.

Aims

The introduction of a novel design of total knee arthroplasty (TKA) must achieve outcomes at least as good as existing designs. A novel design of TKA with a reducing radius of the femoral component and a modified cam-post articulation has been released and requires assessment of the fixation to bone. Radiostereometric analysis (RSA) of the components within the first two postoperative years has been shown to be predictive of medium- to long-term fixation. The aim of this study was to assess the stability of the tibial component of this system during this period of time using RSA.

We recovered 23 meniscal bearings from 18 failed bicompartmental Oxford knee prostheses. They had been implanted for one to nine years. The minimum thickness of the retrieved bearings was measured and compared with the thickness of 25 unused bearings. The mean penetration rate, calculated by two methods, was either 0.043 or 0.026 mm per annum. This compares with 0.19 mm per annum reported for the Charnley hip. The use of a fully congruous meniscal bearing prosthesis can reduce wear in knee arthroplasty to a very low rate

Aims . To investigate whether pre-operative functional mobility is a determinant of delayed inpatient recovery of activities (IRoA) after total knee arthroplasty (TKA) in three periods that coincided with changes in the clinical pathway. Patients and Methods. All patients (n = 682, 73% women, mean age 70 years, standard deviation 9) scheduled for TKA between 2009 and 2015 were pre-operatively screened for functional mobility by the Timed-up-and-Go test (TUG) and De Morton mobility index (DEMMI). The cut-off point for delayed IRoA was set on the day that 70% of the patients were recovered, according to the Modified Iowa Levels of Assistance Scale (mILAS) (a 5-item activity scale). In a multivariable logistic regression analysis, we added either the TUG or the DEMMI to a reference model including established determinants. Results. Both the TUG (Odds Ratio (OR) 1.10 per second, 95% confidence intervals (CI) 1.06 to 1.15) and the DEMMI (OR 0.96 per point on the 100-point scale, 95% CI 0.95 to 0.98) were statistically significant determinants of delayed IRoA in a model that also included age, BMI, ASA score and ISAR score. These associations did not depend on the time period during which the TKA took place, as assessed by tests for interaction. . Conclusion. Functional mobility, as assessed pre-operatively by the TUG and DEMMI, is an independent and stable determinant of delayed inpatient recovery of activities after TKA. Future research, focusing on improvement of pre-operative functional mobility through tailored physiotherapy intervention, should indicate whether such intervention enhances post-operative recovery among high-risk patients. Cite this article: Bone Joint J 2017;99-B:211–17

Substance P is readily detected in the synovial fluid of the knee in which it acts as a powerful inflammatory agent in response to injury and disease. It may be an objective predictor of pain after knee replacement surgery. The level of substance P was measured in the synovial fluid in both knees of 114 patients having unilateral and in 86 patients having bilateral total knee replacement for osteoarthritis. All had severe pain in the knee to be replaced and joint destruction. Substance P was elevated in 73% of replaced knees but not in normal or asymptomatic knees. Good or excellent pain relief was achieved in 97% of patients with an elevated preoperative level of substance P and in 61% of those with a normal preoperative level (p < 0.05 compared with preoperative values)

We are entering a new era with governmental bodies taking an increasingly guiding role, gaining control of registries, demanding direct access with release of open public information for quality comparisons between hospitals. This review is written by physicians and scientists who have worked with the Swedish Knee Arthroplasty Register (SKAR) periodically since it began. It reviews the history of the register and describes the methods used and lessons learned.

Cite this article: Bone Joint Res 2014;3:217–22.

We have reviewed 85 knees in 71 patients after total-condylar posteriorly stabilised (Insall-Burstein) knee replacement with an average follow-up of five years. Excellent or good results were obtained in 90% with an average maximum flexion of 98 degrees. The four poor results (5%) included two with deep infection, one with patellar dislocation and one with loosening. Four other knees (5%) showed signs of probable tibial loosening, but the patients were asymptomatic, the clinical results had not deteriorated with time and lucent lines had not progressed. Varus alignment of the knee and a varus tilt of more than 2 degrees of the tibial component correlated with the incidence of lucent lines around the tibial implant. No patellar stress fractures were seen but impingement symptoms were present in 20%, although they were troublesome in less than half of them. The virtue of the prosthesis lies in its versatility for use in the severely deformed joint

Loosening is a serious problem in total arthroplasty and early detection of bone loss in the vicinity of an implant would help in its investigation. We present a method for the objective evaluation of bone adjacent to metallic implants in which a modified technique of quantitative computed tomography (QCT) is used to reconstruct cross-sectional images with few artefacts. We have used this technique in 19 patients with knee arthroplasties to monitor the changes in bone density around the tibial stem of the prosthesis. In the first weeks after operation all patients showed a decrease in bone density ranging from 0.4% to 3.6% per month. One year after arthroplasty bone density had stabilised and only minor changes were observed. Our work indicates that modified QCT is a sensitive method for the long-term monitoring of the anchorage of implants and allows the early detection of osteolytic changes