Stability of the femoral stem in cementless total hip arthroplasty and PET/CT imaging of adverse reaction to metal debris

Sementittömän lonkan tekonivelleikkauksen onnistumista ikääntyvillä naisilla voi uhata heikentynyt luunlaatu, joka on riski tekonivelen kiinnittymiselle ja stabiliteetille. Tekonivelen liikettä voidaan arvioida radiostereometrisellä analyysillä. Sementittömän lonkan tekonivelen stabiliteetti ikääntyvillä naisilla on väitöskirjan ensimmäinen tutkimusaihe. Toisena tutkittavana aiheena on metallihierrekomplikaation kuvantaminen positroniemissiotietokonetomografialla (PET/TT). Metalli-metalli-liukupintaisista lonkan tekonivelistä irtoaa metallihierrettä, joka voi aiheuttaa tekoniveltä ympäröivien kudosten tulehdusta ja vaurioita. PET/TT soveltuu tulehduksen kuvantamiseen, ja se voisi auttaa metallihierrekomplikaatioiden diagnostiikassa. Kahteen ensimmäiseen osatyöhön valittiin lonkan nivelrikkoa sairastavia naisia. Suurella osalla potilaista todettiin alentunut luuntiheys ennen tekonivelleikkausta. Ensimmäisessä osatyössä arvioitiin sementöimättömän lonkan tekonivelen varsiosan myöhäisvaiheen stabiliteettia yhdeksän vuoden seurannassa. Toisessa osatyössä arvioitiin, vähentääkö luukatolääke tsoledronihappo varsiosan leikkauksen jälkeistä liikettä sekä estääkö tsoledronihappo luuntiheyden laskua varsiosan ympärillä neljän vuoden seurannassa. Kolmannessa osatyössä arvioitiin PET/TT:ssa käytettävien tulehdusmerkkiaineiden, [18F]FDG:n ja [68Ga]sitraatin, kerääntymistä oireisilla metallihierrekomplikaatiopotilailla. Tekonivelen varsiosassa ei tapahtunut merkittävää myöhäisvaiheen liikettä. Tsoledronihappo ei pienentänyt varsiosan alkuvaiheen liikettä, mutta vähensi luuntiheyden laskua varsiosan ympärillä. Sementitön lonkan tekonivel on stabiili myös ikääntyvillä naisilla. Tulehduksellinen metallihierrekomplikaatio kuvautuu paremmin [18F]FDG:lla kuin [68Ga]sitraatilla.The outcome of cementless total hip arthroplasty (THA) in aging women is challenged by impaired bone quality as it can jeopardize implant fixation and stability. Implant migration can be evaluated by means of radiostereometric analysis (RSA), which represents the first object of interest in this thesis. The second object of interest is the positron emission tomography with computed tomography (PET/CT) imaging of adverse reaction to metal debris (ARMD). Metal-on-metal hip arthroplasties generate wear debris that causes periprosthetic tissue inflammation and damage. PET/CT detects sites of inflammation, and therefore could be applicable in the diagnostics of ARMD. In the first two studies, aging females suffering from hip osteoarthritis underwent cementless THA. Preoperative bone mineral density (BMD) assessment showed low BMD in most of the subjects. The first study evaluated the stability of the femoral stems in a nine-year follow-up. The second placebo-controlled trial evaluated the effects of an antiresorptive drug, zoledronic acid, on femoral stem migration and periprosthetic BMD in a four-year follow-up. The third exploratory, controlled, open-label study characterized the PET/CT imaging findings of symptomatic ARMD patients with [18F]FDG and [68Ga]Citrate. The femoral stems did not show significant late migration. Zoledronic acid did not inhibit early implant migration but it reduced periprosthetic bone loss. The cementless femoral stems are stabile even in aging women. The inflammatory ARMD is better visualized with [18F]FDG than with [68Ga]Citrate

A long-lasting bisphosphonate partially protects periprosthetic bone, but does not enhance initial stability of uncemented femoral stems: A randomized placebo-controlled trial of women undergoing total hip arthroplasty

Low bone quality may compromise the success of cementless total hip arthroplasty in high-risk patients such as elderly women. Zoledronic acid is a long-lasting antiresorptive agent, which is known to reduce short-term periprosthetic bone loss. However, its effect on femoral stem stability is not well known. Forty-nine female patients with a mean age of 68 years (range, 51-85 years) scheduled to undergo cementless total hip arthroplasty due to osteoarthritis were randomized in this double-blind, placebo controlled trial to receive a single postoperative infusion of zoledronic acid or placebo. Patients were evaluated for up to four years postoperatively for femoral stem migration measured by radiostereometric analysis, bone mineral density (BMD) measured by dual X-ray absorptiometry, functional recovery, and patient-reported outcome scores. Implant survival was determined at nine years postoperatively. Zoledronic acid did not reduce the femoral stem migration that occurred predominantly during the settling period of the first 3-6 months. Subsequently, all femoral stems were radiographically osseointegrated. Zoledronic acid maintained periprosthetic BMD, while the expected loss of periprosthetic bone during the first 12 months was found in controls. Thereafter, periprosthetic BMD of Gruen zone 7 decreased even in the zoledronic acid group but remained 14.6% higher than that in the placebo group at four years postoperatively. Functional recovery was comparable across the groups. At nine years postoperatively, no revision arthroplasty had been performed. In conclusion, in women at high-risk for low BMD, zoledronic acid had a long-lasting, partially protective effect on periprosthetic bone loss, but the treatment did not enhance the initial femoral stem stability

Good stability of a cementless, anatomically designed femoral stem in aging women: a 9-year RSA study of 32 patients

Background and purpose — We previously reported a transient, bone mineral density (BMD)-dependent early migration of anatomically designed hydroxyapatite-coated femoral stems with ceramic–ceramic bearing surfaces (ABG-II) in aging osteoarthritic women undergoing cementless total hip arthroplasty. To evaluate the clinical significance of the finding, we performed a follow-up study for repeated radiostereometric analysis (RSA) 9 years after surgery.Patients and methods — Of the 53 female patients examined at 2 years post-surgery in the original study, 32 were able to undergo repeated RSA of femoral stem migration at a median of 9 years (7.8–9.3) after surgery. Standard hip radiographs were obtained, and the subjects completed the Harris Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index outcome questionnaires.Results — Paired comparisons revealed no statistically significant migration of the femoral stems between 2 and 9 years post-surgery. 1 patient exhibited minor but progressive RSA stem migration. All radiographs exhibited uniform stem osseointegration. No stem was revised for mechanical loosening. The clinical outcome scores were similar between 2 and 9 years post-surgery.Interpretation — Despite the BMD-related early migration observed during the first 3 postoperative months, the anatomically designed femoral stems in aging women are osseointegrated, as evaluated by RSA and radiographs, and exhibit good clinical function at 9 years.</div

Bilateral low systolic toe pressure and toe-brachial index are associated with long-term mortality in patients with peripheral artery disease

Objective: Based on our previous reports, ipsilateral systolic toe pressure (STP) and toe-brachial index (TBI) have a strong association with midterm cardiovascular and overall mortality as well as with amputation-free survival in patients with symptomatic lower extremity peripheral artery disease (PAD). The effect of the often overlooked contralateral lower limb on patient outcome remains unknown. This study aimed to resolve the significance of contralateral STP (CL_STP) and contralateral TBI for long-term overall and cardiovascular mortality. Methods: This is a retrospective cohort study of 727 consecutive patients with symptomatic lower extremity PAD. All patients admitted to the Department of Vascular Surgery at Turku University Hospital for digital subtraction angiography between January 2009 and August 2011 and for whom STP measurements were available were recruited and observed for up to 7 years. Dates and causes of death were collected from the national cause of death registry of Statistics Finland. Results: In the study cohort, STP was Conclusions: Low STP and TBI of both contralateral and ipsilateral lower extremities are associated with high cardiovascular and overall mortality in symptomatic PAD patients. Bilaterally low STP and TBI are associated with a particularly poor prognosis.Peer reviewe

PET/CT to detect adverse reactions to metal debris in patients with metal-on-metal hip arthroplasty: an exploratory prospective study

Metal-on-metal (MoM) bearings in total hip arthroplasties and hip resurfacing arthroplasties have recently shown a new type of complication: adverse reactions to metal debris (ARMD). ARMD is characterized by local severe inflammation and tissue necrosis leading to implant failures. The gluteal muscle region is important for the patient outcome after revision surgery. This prospective positron emission tomography/computed tomography (PET/CT) study was undertaken to evaluate the characteristics of 2-deoxy-2-[18 F]fluoro-d-glucose ([18 F]FDG) and [68 Ga]Gallium citrate ([68 Ga]Citrate) PET/CT in ARMD patients. [18 F]FDG and [68 Ga]Citrate PET/CT were performed in 18 hip arthroplasty patients: 12 ARMD patients (with 16 MoM hips) and six arthroplasty controls without ARMD. Tracer uptake was evaluated visually, and maximum standardized uptake (SUVmax ) was measured in the gluteal muscle region. ARMD severity was graded by metal artefact reduction sequence-magnetic resonance imaging (MARS-MRI). Periprosthetic [18 F]FDG uptake was observed in 15 of 16 hips, [68 Ga]Citrate uptake in three of 16 hips, respectively. The distribution of tracer uptake resembled infection in three hips. In the gluteal muscle region, the SUVmax of [18 F]FDG was significantly greater in hips with moderate and severe ARMD compared with the controls (P = 0·009 for [18 F]FDG and P = 0·217 for [68 Ga]Citrate). In patients who needed revision surgery, an intraoperative finding of gluteal muscle necrosis was associated with increased local SUVmax as detected by preoperative [18 F]FDG (P = 0·039), but not by [68 Ga]Citrate (P = 0·301). In conclusion, the inflammatory reaction to metal debris in hip arthroplasty patients is best visualized with [18 F]FDG

The role of study engagement in university students' daily experiences : A multilevel test of moderation

The present study investigated the dynamic nature of students' daily experiences and general study engagement using intra-individual assessment. More specifically, we examined individual differences in the relationship between university students' task-specific value and situational emotions and, further, whether first-year study engagement would moderate this association during the first two years of studies. Intra-individual state assessments were conducted via mobile phone-based experience sampling method (ESM) during participants' first (N = 72) and second (N = 56) academic years, resulting in 3089 and 2912 fully completed state questionnaires. In both years, students were asked five times a day over two weeks how important they perceived their current activity and their positive and negative emotions. Using multilevel structural equation modeling, we found that, on average, a higher perception of task-specific value was associated with higher positive emotions and lower negative emotions within individuals. However, individual differences were detected in the value-emotion relations especially during the second academic year. Finally, the findings indicated that overall study engagement, measured at the beginning of the first academic year, predicted between-person differences in these within-person relationships both years.Peer reviewe

Psychological illness is commonly associated with functional gastrointestinal disorders and is important to consider during patient consultation: a population-based study

BACKGROUND: Some individuals with functional gastrointestinal disorders (FGID) suffer long-lasting symptoms without ever consulting their doctors. Our aim was to study co-morbidity and lifestyle differences among consulters and non-consulters with persistent FGID and controls in a defined adult population. METHODS: A random sample of the general adult Swedish population was obtained by a postal questionnaire. The Abdominal Symptom Questionnaire (ASQ) was used to measure GI symptomatology and grade of GI symptom severity and the Complaint Score Questionnaire (CSQ) was used to measure general symptoms. Subjects were then grouped for study by their symptomatic profiles. Subjects with long-standing FGID (n = 141) and subjects strictly free from gastrointestinal (GI) symptoms (n = 97) were invited to attend their local health centers for further assessment. RESULTS: Subjects with FGID have a higher risk of psychological illness [OR 8.4, CI(95)(4.0–17.5)] than somatic illness [OR 2.8, CI(95)(1.3–5.7)] or ache and fatigue symptoms [OR 4.3, CI(95)(2.1–8.7)]. Subjects with psychological illness have a higher risk of severe GI symptoms than controls; moreover they have a greater chance of being consulters. Patients with FGID have more severe GI symptoms than non-patients. CONCLUSION: There is a strong relation between extra-intestinal, mental and somatic complaints and FGID in both patients and non-patients. Psychological illness increases the chance of concomitantly having more severe GI symptoms, which also enhance consultation behaviour

Good stability of a cementless, anatomically designed femoral stem in aging women: a 9-year RSA study of 32 patients

Background and purpose — We previously reported a transient, bone mineral density (BMD)-dependent early migration of anatomically designed hydroxyapatite-coated femoral stems with ceramic–ceramic bearing surfaces (ABG-II) in aging osteoarthritic women undergoing cementless total hip arthroplasty. To evaluate the clinical significance of the finding, we performed a follow-up study for repeated radiostereometric analysis (RSA) 9 years after surgery. Patients and methods — Of the 53 female patients examined at 2 years post-surgery in the original study, 32 were able to undergo repeated RSA of femoral stem migration at a median of 9 years (7.8–9.3) after surgery. Standard hip radiographs were obtained, and the subjects completed the Harris Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index outcome questionnaires. Results — Paired comparisons revealed no statistically significant migration of the femoral stems between 2 and 9 years post-surgery. 1 patient exhibited minor but progressive RSA stem migration. All radiographs exhibited uniform stem osseointegration. No stem was revised for mechanical loosening. The clinical outcome scores were similar between 2 and 9 years post-surgery. Interpretation — Despite the BMD-related early migration observed during the first 3 postoperative months, the anatomically designed femoral stems in aging women are osseointegrated, as evaluated by RSA and radiographs, and exhibit good clinical function at 9 years