Standardising analgesic administration for nurses: a prospective intervention study.

Background Uncontrolled pain reduces quality of life, delays recovery from surgery and can potentially contribute to the development of chronic pain. Strategies to improve pain management are desirable in view of these detrimental outcomes, yet frequently they are predominately medically based despite nurses playing key roles in pain assessment and analgesic administration. Objective To develop an algorithm-based guidance addressing nurses' pain assessment and analgesic administration and investigating its impact on quality of pain management. Setting Two orthopaedic units in a university hospital. Method An interdisciplinary expert panel consisting of physicians, nurses and clinical pharmacists developed an algorithm-based guidance in analgesic administration for nurses. The guidance was based on current guidelines addressing the appropriate use of analgesics. In a prospective intervention study, clinical pharmacists acted as independent monitors who assessed nurses' pain assessment and analgesic administration before (control period: usual care without any further support) and after implementation of the algorithm-based guidance (intervention period). We evaluated patient-nurse contacts for guideline adherence. We predefined guideline adherence (main outcome) as fulfilling all three of the following criteria: (A) nurses' pain intensity assessment, (B) their assessment of the patients' need for analgesics, and (C) analgesic administration depending on patients' individual pain intensity (including choice of prescribed analgesics). Main outcome measure Adherence to pain management guidelines. Results We analysed 706 patient-nurse contacts with 162 patients in the control and 748 contacts with 168 patients in the intervention period. Without support, guidelines were followed in 6 % of the patient contacts. We achieved an increase to 54 % (p < 0.001) after guidance implementation (main outcome). Guideline adherence decreased with rising pain intensity (slope coefficient -0.763, p < 0.001). Conclusion Especially in patients suffering from severe pain, current guidelines were not strictly followed by nurses when administering analgesics. Guideline adherence improved eightfold by implementing an algorithm-based guidance.

Bipolar hip arthroplasty as salvage treatment for loosening of the acetabular cup with significant bone defects.

INTRODUCTION: Revision arthroplasty of the hip is becoming increasingly important in recent years. Early primary arthroplasty and longer life expectancy of the patients increases the number of revision surgery. Revision surgery of hip arthroplasty is major surgery for the patients, especially the elderly, with significant risks concerning the general condition of the patient. The aim of this work is to evaluate the outcome of bipolar hip arthroplasty as a salvage procedure for treatment of loosening of the acetabular cup with significant acetabular bone defects after total hip replacement (THR) in multi-morbid patients. PATIENTS AND METHODS: During the period from January 1(st) 2007 to December 31(st) 2011 19 revision hip surgeries were performed in 19 patients, in which the loosened acetabular cup was replaced by a bipolar head. The examined patient group consisted exclusively of female patients with an average of 75 years. The predominant diagnosis was "aseptic loosening" (84.2%). All patients in our study were multi-morbid. We decided to resort to bipolar hip arthroplasty due to the compromised general condition of patients and the major acetabular bone defects, which were confirmed intraoperatively. The postoperative follow-up ranged from 0.5 to 67 months (average 19.1 months). RESULTS: Evaluation of the modified Harris Hip Score showed an overall improvement of the function of the hip joint after surgery of approximately 45%. Surgery was less time consuming and thus adequate for patients with significantly poor general health condition. We noticed different complications in a significant amount of patients (68.4%). The most common complication encountered was the proximal migration of the bipolar head. The rate of revision following the use of bipolar hip arthroplasty in revision surgery of the hip in our patients was high (21%). Despite the high number of complications reported in our study, we have noticed significant improvement of hip joint function as well as subjective pain relief in the majority of patients. We clearly achieved clinically satisfactory results in 14 patients. CONCLUSION: Bipolar hip arthroplasty is by no means to be regarded as standard procedure in revision surgery of THR. It provides an option or salvage procedure for patients with poor general condition in whom the quickest possible surgical intervention preserving mobility is required. This is particularly true for multi-morbid patients in whom sufficient acetabular fixation is not possible.

Periprosthetic joint infections in modular endoprostheses of the lower extremities: a retrospective observational study in 101 patients.

BACKGROUND: Modular mega-endoprosthesis systems are used to bridge very large bone defects and have become a widespread method in orthopaedic surgery for the treatment of tumours and revision arthroplasty. However, the indications for the use of modular mega-endoprostheses must be carefully considered. Implanting modular endoprostheses requires major, complication-prone surgery in which the limited salvage procedures should always be borne in mind. The management of periprosthetic infection is particularly difficult and beset with problems. Given this, the present study was designed to gauge the significance of periprosthetic infections in connection with modular mega-implants in the lower extremities among our own patients. METHODS: Patients who had been fitted with modular endoprosthesis on a lower extremity at our department between September 1994 and December 2011 were examined retrospectively. A total of 101 patients with 114 modular prostheses were identified. Comprising 30 men (29.7 %) and 71 women (70.3 %), their average age at the time of surgery was 67 years (18-92 years). RESULTS: The average follow-up period was 27 months (5 months and 2 weeks to 14 years and 11 months) and the drop-out rate was about 8.8 %. Altogether, there were 19 (17.7 %) endoprosthesis infections: 3 early infections and 16 late or delayed infections. The pathogen spectrum was dominated by coagulase-negative staphylococci (36 %) and Staphylococcus aureus (16 %), including 26 % multi-resistant pathogens. Reinfection occurred in 37 % of cases of infection. Tumours were followed by significantly fewer infections than the other indications. Infections were twice as likely to occur after previous surgery. CONCLUSION: In our findings modular endoprostheses (18 %) are much more susceptible to infection than primary endoprostheses (0.5-2,5 %). Infection is the most common complication alongside the dislocation of proximal femur endoprostheses. Consistent, radical surgery is essential - although even with an adequate treatment strategy, the recurrence rate is very high. Unfortunately, the functional results are frequently unsatisfactory, with amputation often being the last resort. Therefore, the indication for implantation must be carefully considered and discussed in great detail, especially in the case of multimorbid patients with previous joint infections.

Diagnostic work-up strategy for periprosthetic joint infections after total hip and knee arthroplasty: a 12-year experience on 320 consecutive cases.

BACKGROUND: Elective knee and hip arthroplasty is followed by infections in currently about 0.5-2.0 % of cases - a figure which is on the increase due to the rise in primary implants. Correct diagnosis early on is essential so that appropriate therapy can be administered. This work presents a retrospective analysis of the diagnoses of patients suffering infections after total hip or knee arthroplasty. METHODS: 320 patients with prosthetic joint infection (PJI) following knee or hip arthroplasty were identified. They comprised a) 172 patients with an infection after total hip arthroplasty (THA): 56 % females (n = 96) and 44 % males (n = 76) with a mean age of 70.9 (39-92) years; and 148 patients with an infection after total knee arthroplasty (TKA): 55 % females (n = 82) and 45 % males (n = 66) with a mean age of 70.7 (15-87) years. RESULTS: Although significantly more TKA than THA patients reported pain, erythema, a burning sensation and swelling, no differences between the two groups were observed with respect to dysfunction, fever or fatigue. However, significant differences were noted in the diagnosis of loosening (THA 55 %, TKA 31 %, p < 0.001) and suspected infection using conventional X-rays (THA 61 %, TKA 29 %, p < 0.001). FDG-PET-CT produced very good results in nearly 95 % of cases. There were no differences between THA and TKA patients regarding levels of inflammation markers. Histological evaluation proved to be significantly better than microbiological analysis. SUMMARY: The clinical picture may be non-specific and not show typical inflammatory symptoms for a long time, particularly in PJI of the hip. As imaging only provides reliable conclusions after the symptoms have persisted for a long time, morphological imaging is not suitable for the detection of early infections. FDG-PT-CT proved to be the most successful technique and is likely to be used more frequently in future. Nevertheless, there are currently no laboratory parameters which are suitable for the reliable primary diagnosis of PJI. Diagnosis requires arthrocentesis, and the fluid obtained should always be examined both microbiologically and histologically.

On the permanent hip-stabilizing effect of atmospheric pressure.

Hip joint dislocations related to total hip arthroplasty (THA) are a common complication especially in the early postoperative course. The surgical approach, the alignment of the prosthetic components, the range of motion and the muscle tone are known factors influencing the risk of dislocation. A further factor that is discussed until today is atmospheric pressure which is not taken into account in the present THA concepts. The aim of this study was to investigate the impact of atmospheric pressure on hip joint stability. Five joint models (Ø 28-44 mm), consisting of THA components were hermetically sealed with a rubber capsule, filled with a defined amount of fluid and exposed to varying ambient pressure. Displacement and pressure sensors were used to record the extent of dislocation related to intraarticular and ambient pressure. In 200 experiments spontaneous dislocations of the different sized joint models were reliably observed once the ambient pressure was lower than 6.0 kPa. Increasing the ambient pressure above 6.0 kPa immediately and persistently reduced the joint models until the ambient pressure was lowered again. Displacement always exceeded half the diameter of the joint model and was independent of gravity effects. This experimental study gives strong evidence that the hip joint is permanently stabilized by atmospheric pressure, confirming the theories of Weber and Weber (1836). On basis of these findings the use of larger prosthetic heads, capsular repair and the deployment of an intracapsular Redon drain are proposed to substantially decrease the risk of dislocation after THA.

Non-union of osteoporotic vertebral fractures - identification and treatment of an underestimated pathology in elderly patients with persistent back pain.

OBJECTIVE: Non-union of osteoporotic vertebra fractures are a seldom entity. However, when back pain persists in the course of conservatively treated osteoporotic vertebra fractures, a non-union should be considered. We thus sought to validate our diagnostic algorithm in patients with known osteoporotic vertebra fractures presenting persistent back pain and advert to the diagnosis and treatment of vertebral non-unions. PATIENTS AND METHODS: Patients admitted with preexisting osteoporotic vertebra fractures and therapy-resistant back pain were retrospectively analysed. All admitted patients were subject to standard plain radiographs in erect position and conventional CT or MR imaging of the spine, respectively. In addition, patients with suspected non-union were subject to lateral fulcrum radiographs in supine position. RESULTS: From a total of 172 admitted patients, four patients presented with non-union of a fractured osteoporotic vertebra (2%). The subsequent surgical therapy included cement-augmented rod-and-screw stabilization, with or without additional correction of deformity, and kyphoplasty (N = 3) or kyphoplasty alone (N = 1). All surgical interventions were successful in pain reduction and allowed immediate and improved postoperative mobilisation. CONCLUSIONS: Non-union of osteoporotic vertebra fractures must be considered when symptoms outlast conservative treatment. In these cases, plain lateral fulcrum radiographs are a simple and effective adjunct to the conventional diagnostic methods. Surgical stabilization then proves to be the effective treatment of choice.

Diagnosis and treatment of extraabdominal desmoid fibromatosis.

INTRODUCTION: The desmoid fibromatosis is a very rare connective tissue disease which is recognized as semimalignant. The aim of this work is to review the relevant literature and to analyze the management of our patient collective. MATERIAL AND METHOD: Surgery was performed on 7 patients with extraabdominal desmoid fibromatosis between August 1998 and May 2007. MRI examination as well as biopsy was carried out in all cases. All patients were operated on; the mean follow up was 4 years (1-7). Upon follow up, every patient has undergone clinical and MRI examination. RESULTS: The results show that we have achieved R0 resection in 4 cases and R1 in two cases and Rx in one case. In 4 patients, no recurrence was observed after the single surgery performed in our hospital. In 2 patients a single revision surgery was performed in each case and yielded no further recurrence. In only one case, multiple surgeries (one primary and two revision surgeries) were necessary, after which no recurrence was reported. CONCLUSION: The early diagnosis of the disease is of utmost importance to the success of the outcome. MRI examination and biopsy are mandatory. Surgery is the therapy of choice. The recurrence rate is high and is linked to the difficulty of recognition of the exact infiltrative extent of the tumour. This necessitates a close follow-up.

Therapeutic options to prevent recurrence of an aggressive aneurysmatic bone cyst of the cervical spine of a 16 year old boy - a case report.

The aneurysmatic bone cyst (ABC) is a benign primary bone tumour. If located in the cervical spine, its expansive growth and destructive behaviour may lead to instability and serious neurological impairment. We report a case of a 16-year-old boy with an aggressive ABC in the 7th cervical vertebra. Computertomographic and magnetic resonance imaging revealed the envelopment of the left 7th and 8th spinal nerve along with the anterior displacement of the left vertebral artery. The interdisciplinary surgical strategy consisted of a partially incomplete cyst resection, subtotal spondylectomy with posterior screw-and-rod fixation from C6-Th1, iliac crest bone grafting and anterior plating from C6-Th1. With regard to the high rate of recurrence after incomplete resection published in the recent literature, the patient was postoperatively treated by megavoltage radiotherapy with a total dose of 30Gy (daily dose of 1.8 Gy for 3 weeks). The clinical and radiographic follow-up showed complete recovery of all neurologic impairments and no signs of tumour recurrence at 3, 6 and 12 months after surgery. This case highlights diverse treatment regimens and shall outline the challenge and the problems of the interdisciplinary decision-making in adolescents presenting with ABC in high-demanding anatomical regions.

In vivo glenohumeral analysis using 3D MRI models and a flexible software tool: feasibility and precision.

PURPOSE: To implement a PC-based morphometric analysis platform and to evaluate the feasibility and precision of MRI measurements of glenohumeral translation. MATERIALS AND METHODS: Using a vertically open 0.5T MRI scanner, the shoulders of 10 healthy subjects were scanned in apprehension (AP) and in neutral position (NP), respectively. Surface models of the humeral head (HH) and the glenoid cavity (GC) were created from segmented MR images by three readers. Glenohumeral translation was determined by the projection point of the manually fitted HH center on the GC plane defined by the two main principal axes of the GC model. RESULTS: Positional precision, given as mean (extreme value at 95% confidence level), was 0.9 (1.8) mm for the HH center and 0.7 (1.6) mm for the GC centroid; angular GC precision was 1.3 degrees (2.3 degrees ) for the normal and about 4 degrees (7 degrees ) for the anterior and superior coordinate axes. The two-dimensional (2D) precision of the HH projection point was 1.1 (2.2) mm. A significant HH translation between AP and NP was found. CONCLUSION: Despite a limited quality of the underlying model data, our PC-based analysis platform allows a precise morphometric analysis of the glenohumeral joint. The software is easily extendable and may potentially be used for an objective evaluation of therapeutical measures.

Finite element analysis of shear stresses at the implant-bone interface of an acetabular press-fit cup during impingement.

After total hip replacement (THR) impingement of the implant components causes shear stresses at the acetabular implant-bone interface. In the current study the finite element method (FEM) was applied to analyse the shear stresses at a fully bonded implant-bone interface assuming total ingrowth of the cup. The FE model of a press-fit acetabular component and the proximal part of the femoral component incorporates non-linear material and large sliding contact. The model was loaded with a superior-medial joint load of 435 N simulating a two-legged stance. Starting at initial impingement, the femoral component was medially rotated by 20 degrees . The peak tilting shear stress of -2.6 MPa at the impingement site takes effect towards the pole of the cup. The torsional shear stress at the impingement site is zero. On each side of the impingement site, there are extrema of torsional shear stress reaching -1.8 and 1.8 MPa, respectively. The global peak shear stress during impingement may indicate a possible starting point for cup loosening. The pattern of the torsional shear stresses suggests that besides the symmetric lever-out, an additional asymmetrical tilting of the cup occurs that can be explained by the orientation of the applied joint load.