Even "Cementless" Surgeons Use Cement.

BACKGROUND: Patients presenting with hip arthritis have huge variability in anatomy, bone quality, and functional expectation. These can contribute to a varying degree of complexity on both the femoral and acetabular sides. Surgeons should be aware of all the various options in fixation, bearing surface, and surgical technique. METHODS: In this article, based on a presentation given at the recent American Association of Hip and Knee Surgeons meeting in Dallas, we will discuss why and how cemented fixation can, and indeed should, be considered when making decisions regarding how a primary, complex primary, or revision hip arthroplasty should be performed. RESULTS: We will review the evidence, surgical technique, and indications for cemented fixation in primary and complex primary surgery. In addition, we will discuss the potential benefits at revision of previous cemented fixation. CONCLUSION: We hope to support the concept that even cementless surgeons should also use cement.

A systematic review of Vancouver B2 and B3 periprosthetic femoral fractures.

AIMS: The aim of this study was to investigate the outcomes of Vancouver type B2 and B3 fractures by performing a systematic review of the methods of surgical treatment which have been reported. MATERIALS AND METHODS: A systematic search was performed in Ovid MEDLINE, Embase and the Cochrane Central Register of Controlled Trials. For inclusion, studies required a minimum of ten patients with a Vancouver type B2 and/or ten patients with a Vancouver type B3 fracture, a minimum mean follow-up of two years and outcomes which were matched to the type of fracture. Studies were also required to report the rate of re-operation as an outcome measure. The protocol was registered in the PROSPERO database. RESULTS: A total of 22 studies were included based on the eligibility criteria, including 343 B2 fractures and 167 B3 fractures. The mean follow-up ranged from 32 months to 74 months. Of 343 Vancouver B2 fractures, the treatment in 298 (86.8%) involved revision arthroplasty and 45 (12.6%) were treated with internal fixation alone. A total of 37 patients (12.4%) treated with revision arthroplasty and six (13.3%) treated by internal fixation only underwent further re-operation. Of 167 Vancouver B3 fractures, the treatment in 160 (95.8%) involved revision arthroplasty and eight (4.8%) were treated with internal fixation without revision. A total of 23 patients (14.4%) treated with revision arthroplasty and two (28.6%) treated only with internal fixation required re-operation. CONCLUSION: A significant proportion, particularly of B2 fractures, were treated without revision of the stem. These were associated with a higher rate of re-operation. The treatment of B3 fractures without revision of the stem resulted in a high rate of re-operation. This demonstrates the importance of careful evaluation and accurate characterisation of the fracture at the time of presentation to ensure the correct management. There is a need for improvement in the reporting of data in case series recording the outcome of the surgical treatment of periprosthetic fractures. We have suggested a minimum dataset to improve the quality of data in studies dealing with these fractures. Cite this article: Bone Joint J 2017;99-B(4 Supple B):17-25.

Angular default mode network connectivity across working memory load.

Initially identified during no-task, baseline conditions, it has now been suggested that the default mode network (DMN) engages during a variety of working memory paradigms through its flexible interactions with other large-scale brain networks. Nevertheless, its contribution to whole-brain connectivity dynamics across increasing working memory load has not been explicitly assessed. The aim of our study was to determine which DMN hubs relate to working memory task performance during an fMRI-based n-back paradigm with parametric increases in difficulty. Using a voxel-wise metric, termed the intrinsic connectivity contrast (ICC), we found that the bilateral angular gyri (core DMN hubs) displayed the greatest change in global connectivity across three levels of n-back task load. Subsequent seed-based functional connectivity analysis revealed that the angular DMN regions robustly interact with other large-scale brain networks, suggesting a potential involvement in the global integration of information. Further support for this hypothesis comes from the significant correlations we found between angular gyri connectivity and reaction times to correct responses. The implication from our study is that the DMN is actively involved during the n-back task and thus plays an important role related to working memory, with its core angular regions contributing to the changes in global brain connectivity in response to increasing environmental demands. Hum Brain Mapp 38:41-52, 2017. © 2016 Wiley Periodicals, Inc.

Default mode network connectivity during task execution.

Initially described as task-induced deactivations during goal-directed paradigms of high attentional load, the unresolved functionality of default mode regions has long been assumed to interfere with task performance. However, recent evidence suggests a potential default mode network involvement in fulfilling cognitive demands. We tested this hypothesis in a finger opposition paradigm with task and fixation periods which we compared with an independent resting state scan using functional magnetic resonance imaging and a comprehensive analysis pipeline including activation, functional connectivity, behavioural and graph theoretical assessments. The results indicate task specific changes in the default mode network topography. Behaviourally, we show that increased connectivity of the posterior cingulate cortex with the left superior frontal gyrus predicts faster reaction times. Moreover, interactive and dynamic reconfiguration of the default mode network regions' functional connections illustrates their involvement with the task at hand with higher-level global parallel processing power, yet preserved small-world architecture in comparison with rest. These findings demonstrate that the default mode network does not disengage during this paradigm, but instead may be involved in task relevant processing.

Periprosthetic fractures around hip hemiarthroplasty performed for hip fracture.

UNLABELLED: Hip fracture is associated with considerable morbidity and mortality and occurs in an elderly and infirm group of patients. Periprosthetic fracture after hip hemiarthroplasty is a serious complication. In this study, we have reviewed our experience of this injury. The outcome measures used were fracture union, mortality, infection and requirement for further surgery. METHOD: We identified a cohort of 79 patients who sustained periprosthetic fractures after hip hemiarthroplasty from a prospective hip fracture database of 8354 patients (3611 were treated with hemiarthroplasty). Seventy-two percent were female and the mean age was 86 years at time of periprosthetic fracture. RESULTS: Sixty-two fractures occurred around uncemented prostheses (Austin Moore n=61); the remainder occurred around cemented prostheses. The mean time from hip fracture surgery to periprosthetic fracture was 35 months (median time 5 months). Fractures were classified according to the Vancouver system. Fifteen percent (n=12) were type A fractures, 26% (n=21) were type B1 fractures, 41% (n=32) were type B2 fractures, 9% (n=7) were type B3 fractures and 9% (n=7) were type C fractures. Twenty-eight patients underwent open reduction internal fixation (ORIF), 36 required revision surgery, one required fixation and simultaneous revision and 14 were treated non-operatively. Eleven percent (n=9) died within 1 month of periprosthetic fracture, 23% had died by 3 months, 34% by 1 year and 49% by 2 years. Nineteen patients (24%) died before fracture union had occurred. Fracture union occurred in 97% of the remaining cases (58/60). Two patients developed nonunion requiring revision surgery (3%), and three patients developed deep infection requiring debridement (4%), one patient had an infection at the time of the periprosthetic fracture requiring a planned two-stage revision, one patient sustained a second periprosthetic fracture and two patients underwent superficial wound debridement (3%). The incidence of periprosthetic fracture at our institution since 1999 is 1.7% (62 of 3611 patients). The incidence rate after uncemented Austin Moore stem was 2.3% (54/2378) and cemented Exeter stem was 0.5% (4/812); Fisher's exact test p=0.004. CONCLUSIONS: This article reports satisfactory outcomes in this complex group of patients. We have established the incidence of 1.7%, with relatively low rates of nonunion, infection and other complications. The mortality rate has been established, and survivorship analysis has identified an increased rate of fracture around the Austin Moore prosthesis.

Critical thresholds for cerebrovascular reactivity after traumatic brain injury.

INTRODUCTION: Pressure-reactivity index (PRx) is a useful tool in brain monitoring of trauma patients, but the question remains about its critical values. Using our TBI database, we identified the thresholds for PRx and other monitored parameters that maximize the statistical difference between death/survival and favorable/unfavorable outcomes. We also investigated how these thresholds depend on clinical factors such as age, gender and initial GCS. METHODS: A total of 459 patients from our database were eligible. Tables of 2 × 2 format were created grouping patients according to survival/death or favorable/unfavorable outcomes and varying thresholds for PRx, ICP and CPP. Pearson's chi square was calculated, and the thresholds returning the highest score were assumed to have the best discriminative value. The same procedure was repeated after division according to clinical factors. RESULTS: In all patients, we found that PRx had different thresholds for survival (0.25) and for favorable outcome (0.05). Thresholds of 70 mmHg for CPP and 22 mmHg for ICP were identified for both survival and favorable outcomes. The ICP threshold for favorable outcome was lower (18 mmHg) in females and patients older than 55 years. In logistic regression models, independent variables associating with mortality and unfavorable outcome were age, GCS, ICP and PRx. CONCLUSION: The prognostic role of PRx is confirmed but with a lower threshold of 0.05 for favorable outcome than for survival (0.25). Results for ICP are in line with current guidelines. However, the lower value in elderly and in females suggests increased vulnerability to intracranial hypertension in these groups.

Comparison between a Constrained Condylar and a Rotating Hinge in revision knee surgery.

The performance of Constrained Condylar and Rotating Hinge types of total knee replacement was compared by mechanical testing, by using the Knee Society Clinical and Radiographic evaluations, and by a self-assessment questionnaire. In mechanical tests to evaluate varus strength, Constrained Condylars developed at least 6 degrees of varus rotation, but there was minimal varus rotation in the Rotating Hinges. This was reflected in the stability scores in the Knee Society evaluation. The shorter stems used in the Constrained Condylars resulted in a higher variation in femoral-tibial angles, and a smaller than ideal valgus angle. Radiographically, the only radiolucent lines observed were those adjacent to the joint itself, and there was no difference between the two types of total knee replacement. From the questionnaire, there was a high correlation in the performances between the operated and non-operated knees in the Rotating Hinge group. This indicated the Hinges were capable of matching their performance to a required level, thereby producing a better overall clinical result. In summary, the study indicated that a Rotating Hinge type should be given greater consideration, particularly if the disadvantages of larger bone resection and longer stems could be overcome.

Two-stage uncemented revision hip arthroplasty for infection.

We treated 50 consecutive patients with infected total hip arthroplasties according to a standard protocol. Previous surgery to eradicate the infection had been attempted in 13 patients and discharging sinuses were present in 20. Aspiration arthrography was routinely carried out before our interventions. The first stage was a meticulous removal of all foreign and potentially infected material. Samples were taken for culture and a thorough lavage carried out. Antibiotic-loaded beads were placed in the femoral shaft and an antibiotic-loaded cement ball in the acetabulum. At the second stage an uncemented arthroplasty was introduced. Bone allograft was used in 18 patients. The interval between procedures was usually three weeks, but this was extended if the wound was slow to heal or there was extensive bony destruction. Appropriate antibiotics were given for three months. At a mean follow-up of 5.8 years the rate of reinfection was 8% (4 patients). Two of these patients have had another, successful, two-stage revision. At this medium-term review, a satisfactory clinical and radiological outcome was obtained in all except two patients.

An unexpected complication of DVT prophylaxis.

We report a case in which a complication of routine chemoprophylaxis with subcutaneous low-molecular-weight heparin led to the postponement of a total hip replacement. This unusual reaction reinforces the current debate regarding the use of chemoprophylaxis for joint replacement surgery.

The posterior Monteggia: a pathological lesion?

Ulnar fracture with posterior dislocation of the radial head is thought to be a relatively rare injury. We have recently treated six patients with this posterior Monteggia fracture dislocation. Five of these patients were on long-term corticosteroid therapy. The pathophysiology, treatment and outcome of this complex injury are discussed.

Burn injury and management in Liberia.

Burn care in developing countries remains a challenge. This paper reviews the acute burn care of 21 patients admitted during a 1-year period to a hospital in Liberia. Lack of supplies and education, coupled with the local belief system, reflect on patient management. The study population totalled 21 patients, ranging from 1 to 62 years of age. TBSA burns ranged from 2 to 60 per cent (mean 21 per cent), 61 per cent of patients were grafted. The time between burn and graft varied between 5 and 96 days (mean 29.8). Graft take varied between 40 and 100 per cent (mean 81 per cent). Of the grafted patients 66.6 per cent received blood (average 732 ml). At the time of presentation 61.9 per cent of patients had other illness. The average number of hospital days was 37.9 (range 2-76). The mortality rate was 14.2 per cent. When managing burns in a developing country, adoption of a simple, clearly defined method of treatment, together with education of the care-givers, is suggested. As in the developed world, however, prevention is the critical factor.

Analysis of life expectancy and living status of elderly patients surviving a burn injury.

This study evaluates the long-term outcome of elderly patients discharged from hospital after a burn injury. Ninety-three patients over the age of 60 years, admitted to a regional burn center, were included in the study from January 1981 to January 1986. The in-hospital mortality rate was 49.4%. Patients' living status was graded according to dependency: 47% of patients were reduced to a more dependent living status on discharge, and 36% of the survivors were followed up for between 1 and 5 years. During this time seven (19.4%) patients died, three (8.3%) became more independent, four (11.1%) less independent. Life table analysis of discharged patients showed no accelerated death rate in comparison with the normal population. The high mortality associated with burns in the elderly was confirmed. Half the survivors were at least temporarily less independent. Projected life expectancy for the elderly surviving a burn is comparable with his/her uninjured counterpart.

Antibody response to xenogeneic proteins in burned patients receiving cultured keratinocyte grafts.

Cultured keratinocytes (CK) have been used to resurface large burn wounds with some success. These CK are grown in the presence of fetal bovine serum (FBS) and mouse fibroblasts (MF). Serum from ten patients who received CK grafts as part of burn wound coverage was studied by ELISA technique for antibody to these xenogeneic antigens. All patients had some amount of antibody to FBS but no detectable antibody to MF. The amount of antibody to FBS varied between patients and with respect to time after graft application. Generally, the levels of antibody to FBS were moderate by 30 days, declined, and then rose slowly by 5 to 6 months. The majority of antibody to FBS was against bovine serum albumin (BSA), demonstrated by Western blot technique. The presence of such antibody to FBS might produce clinical problems of graft rejection, anaphylaxis, and serum sickness in patients receiving CK grown in FBS supplemental medium. Further investigation will need to determine the likelihood and potential severity of such clinical problems.