The incidence of knee arthroplasty for primary osteoarthritis grows rapidly among baby boomers: A population‐based study in Finland

Objective

Total knee arthroplasty (TKA) is a commonly used treatment for severe primary knee osteoarthritis (OA) that is refractory to conservative treatment. Despite the presumed increase in the use of this treatment modality in younger patients, there are few published data concerning this. The aim of our study was to examine the changes in the age‐ and sex‐standardized incidence of TKA and unicondylar knee arthroplasty (UKA) in Finland during 1980–2006 and to identify factors that might affect the incidence during this period.

Methods

We obtained data on UKAs and TKAs from the Finnish Arthroplasty Registry and population data from Statistics Finland to analyze the incidence of UKAs and TKAs in Finland for the period 1980–2006. The effects of sex, age group, and hospital volume on the incidence of these procedures were also evaluated.

Results

The annual cumulative incidence of UKAs and TKAs has increased rapidly from 1980 to 2006 among 30–59‐year‐old inhabitants of Finland. For UKAs, the incidence increased from 0.2 per 100,000 inhabitants to 10 per 100,000, and for TKAs, the incidence increased from 0.5 per 100,000 to 65 per 100,000. The incidence remained higher among women during the entire study period. Most of the increase occurred among patients ages 50–59 years. The incidence grew more rapidly in low‐volume and intermediate‐volume hospitals.

Conclusion

We demonstrated a rapid increase in the incidence of arthroplasty among patients with primary knee OA in Finland, especially in those ages 50–59 years. There was no single explanatory factor behind this finding, although some of the growth might be due to the increased incidence noted in low‐ and intermediate‐volume hospitals.

     

Ex vivo MR microimaging of neuronal damage after kainate-induced status epilepticus in rat: correlation with quantitative histology.

The present study was designed to investigate whether T(2)-weighted signal changes obtained by microimaging of paraformaldehyde-fixed brain correlate with the histologically quantified damage in a model of status epilepticus (SE) induced by kainic acid in the rat. Animals were killed at several time points up to 8 weeks after a single intraperitoneal kainate (KA) injection (9 mg/kg). Perfusion-fixed brains were embedded in gelatin for MR microimaging at 9.4T. After the MRI analysis, the gelatin was removed and the brains were cryoprotected and processed for quantitative histology. Severity of neuronal damage and gliosis were assessed from thionin-stained serial sections. Correlative analysis of microimaging and histology data was done in the hippocampus, amygdala, parietal rhinal cortex (PaRH), piriform cortex (Pir), and entorhinal cortex. The relative signal intensities in T(2)-weighted images correlate with the severity of neuronal damage in the matched histological sections (correlation coefficients of 0.752-0.826). Our data show that MR microimaging ex vivo detects the degree of neuronal damage and its anatomical distribution after KA-induced SE, thus providing a useful tool for detecting the dynamics of progressive neuronal damage after prolonged seizures.     

Ubiquitin C-terminal hydrolase L1 after out-of-hospital cardiac arrest

Background

We studied the prognostic ability of serum ubiquitin C-terminal hydrolase L1 (UCH-L1) after out-of-hospital cardiac arrest (OHCA), compared to that of neuron-specific enolase (NSE).

Methods

In this post-hoc analysis of the FINNRESUSCI study, we measured serum concentrations of UCH-L1 in 249 OHCA patients treated in 21 Finnish intensive care units in 2010–2011. We evaluated the ability of UCH-L1 to predict unfavourable outcome at 12 months (defined as cerebral performance category 3–5) by assessing the area under the receiver operating characteristic curve (AUROC), in comparison with NSE.

Results

The concentrations of UCH-L1 were higher in patients with unfavourable outcome than for those with favourable outcome: median concentration 10.8 ng/mL (interquartile range, 7.5–18.5 ng/mL) versus 7.8 ng/mL (5.9–11.8 ng/mL) at 24 h (p < .001), and 16.2 ng/mL (12.2–27.7 ng/mL) versus 11.5 ng/mL (9.0–17.2 ng/mL) (p < .001) at 48 h after OHCA. For UCH-L1 as a 12-month outcome predictor, the AUROC was 0.66 (95% confidence interval, 0.60–0.73) at 24 h and 0.66 (0.59–0.74) at 48 h. For NSE, the AUROC was 0.66 (0.59–0.73) at 24 h and 0.72 (0.65–0.80) at 48 h. The prognostic ability of UCH-L1 was not different from that of NSE at 24 h (p = .82) and at 48 h (p = .23).

Conclusion

Concentrations of UCH-L1 in serum were higher in patients with unfavourable outcome than in those with favourable outcome. However, the ability of UCH-L1 to predict unfavourable outcome after OHCA was only moderate and not superior to that of NSE.     

Intraepithelial lymphocytes bearing the γ/δ receptor in the oral and jejunal mucosa in patients with dermatitis herpetiformis

Lymphocytes bearing T cell receptor (TcR) γ/δ are increased in the jejunal mucosa of patients with dermatitis herpetiformis (DH) and coeliac disease. In this study, we examined whether increased numbers of γ/δ TcR positive lymphocytes occur in the oral mucosa of patients with DH. Oral and jejunal rnucosal biopsies were taken from 13 newly diagnosed and 13 gluten free diet (GFD)-treated patients with DH. Monoclonal antibodies and avidin-biotin peroxidase method was used for staining, and TcR positive cells were counted from the buccal and jejunal epithelium. Very few γ/δ TcR positive lymphocytes were seen in the buccal epithelium of untreated or GFD-treated DH patients (median 0.4 and 0.3 cells/mm²), whereas α/β TcR positive lymphocytes were frequent in both groups of DH patients (154 and 250 cells/mm²) and healthy controls (135 cells/mm²). The numbers of γ/δ TcR positive intraepithelial lymphocytes were significantly increased in the jejunum of both untreated (43 cells/mm) and GFD-treated (27 cells/mm) DH patients compared to control patients (2.2 cells/mm). The present study did not, therefore, disclose any evidence for active recruitment of γ/δ TcR positive lymphocytes in the oral epithelium, but showed substantial amounts of intraepithelial γ/β TcR positive lymphocytes both in DH patients and healthy controls.     

Accumulation of Bisphosphonates in Human Artery and their Effects on Human and Rat Arterial Function in vitro

Abstract: Clodronate, etidronate and pamidronate are bisphosphonates introduced in the treatment of hypercalcaemia and osteoporosis. Interestingly, they also inhibit development of experimental atherosclerosis and affect smooth muscle tone of isolated rat tail artery. We have studied in vitro whether these hydrophilic compounds 1) accumulate in the wall of the human artery, 2) influence human arterial tone, and 3) interfere with the vascular action of L-type Ca²⁺ antagonists. Human internal mammary artery rings were incubated with ¹⁴C-labelled bisphosphonates. After a 2-hr incubation, the ratios of artery-to-incubate concentrations with 4 and 40 μmol/1 of clodronate were, respectively, 3.0+0.5 (mean+S.E.M.) and 1.3+0.2, with 4 and 40 μmol/1 of etidronate 7.4+0.9 and 3.2+0.4, and with 0.4 and 4 μmol/1 of pamidronate 4.7+0.7 and 3.9+0.8. Both tested bisphosphonates, clodronate and pamidronate, reduced the arterial contractile force induced by α-adrenergic stimulation with noradrenaline and membrane depolarization with high concentration of KCl. Clodronate also decreased the arterial contraction induced by cumulative addition of Ca²⁺ with KCl as the agonist, and had an additive inhibitory effect on this response with the L-type Ca²⁺-channel blocker nifedipine. The results demostrate that 1) bisphosphonates accumulate markedly in human artery, 2) clodronate and pamidronate reduce human arterial contactile force to α-adrenergic and depolarizing stimuli, and 3) as shown with clodronate, bisphosphonates may exert an additive inhibitory effect on human arterial contractions with an L-type Ca²⁺-channel blocker.     

Effect of ultrasound therapy on bone healing of lateral malleolar fractures of the ankle joint fixed with bioabsorbable screws

Background We investigated the effect of low-intensity ultrasound on bone healing in bioabsorbable self-reinforced poly-l-lactic acid (SR-PLLA) screw-fixed lateral malleolar fractures. The study design was prospective, randomized, double-blind, and placebo-controlled.Methods A total of 22 fractures were fixed with one SR-PLLA screw. All the patients were instructed to use an ultrasound device 20 min daily for 42 days without knowing whether it was active or inactive. Eleven patients had active and eleven sham ultrasound devices. The causes of error during treatment with head module placement and attachment to the convex surface of the lateral distal fibula were minimized by careful targeting and using coupling gel. Radiological fracture healing was assessed by radiographs and multidetector computed tomography (CT) scans in a blinded manner by a radiologist and orthopedic surgeons.Results The overall compliance to the daily ultrasound treatments was good. All wounds healed uneventfully, and no foreign body reactions were observed. No difference was observed between the groups regarding either fracture line visualization or callus formation assessed by plain radiographs. In the CT images at 9 weeks, the share of the endosteal united fracture line compared to the non-united fracture line was slightly higher in the active ultrasound device group than in the sham ultrasound device group, but the difference was not statistically significant.Conclusion The study indicates that the biocompatibility of ultrasound therapy and bioabsorbable SR-PLLA screw fixation is good. There was no obvious effect of low-intensity ultrasound on lateral malleolar fracture healing. However, the relatively small number of patients must be kept in mind when interpreting our results. It is also important to limit any conclusions based on the present study to malleolar fractures fixed with the SR-PLLA screw.