18F FDG-PET/CT has poor diagnostic accuracy in diagnosing shoulder PJI.

PURPOSE: Chronic low-grade periprosthetic joint infection (PJI) of a shoulder replacement can be challenging to diagnose. 18F-FDG PET/CT is suggested as a modality to diagnose lower-limb PJI, but no studies on shoulder replacements exist. The aim of this study was therefore to determine the diagnostic accuracy of 18F-FDG PET/CT in diagnosing chronic PJI of the shoulder. METHODS: Patients evaluated for a failed shoulder replacement during a 3-year period were prospectively included in the study. All patients underwent pre-operative 18F-FDG PET/CT, and were evaluated for signs of infection by three independent reviewers using shoulder-specific criteria. Interrater-agreement was calculated between the reviewers. If the patient had revision surgery, biopsy specimens were obtained and cultured with bacterial growth in the cultures serving as gold standard of infection. RESULTS: A total of 86 patients were included in the study. Nine patients were 18F-FDG PET/CT positive for infection, with only three true positive. Using the gold standard, infection was diagnosed after revision surgery in 22 cases. All infections were chronic and caused by low-virulent microbes. The sensitivity of 18F-FDG PET/CT was 0.14 95% CI (0.03-0.36), specificity 0.91 95% CI (0.81-0.97), positive predictive value was 0.40 95% CI (0.15-0.71) and negative predictive value 0.71 95% CI (0.67-0.75). The inter-observer agreement was 0.56 (Fleiss' kappa), indicating moderate agreement of the visual FDG-PET evaluation using the shoulder-specific criteria. CONCLUSION: 18F-FDG PET/CT has poor diagnostic accuracy in diagnosing low-grade PJI of the shoulder. 18F-FDG PET/CT cannot be recommended as a part of the routine preoperative workup to diagnose low-grade infection of a shoulder replacement.

The checkpoint kinases Chk1 and Chk2 regulate the functional associations between hBRCA2 and Rad51 in response to DNA damage.

The cellular response to the introduction of double strand DNA breaks involves complexes of protein interactions that govern cell cycle checkpoint arrest and repair of the DNA lesions. The checkpoint kinases Chk1 and Chk2 phosphorylate the carboxy-terminal domain of hBRCA2, a protein involved in recombination-mediated DNA repair (HRR) and replication fork maintenance. Cells deficient in hBRCA2 are hypersensitive to DNA damaging agents. Phosphorylation of the residue in hBRCA2 targeted by the Chk1 and Chk2 kinases regulates its interaction with Rad51. Furthermore, the cell line lex1/lex2, which lacks the carboxy-terminal domain containing the phosphorylated residue, does not support localization of Rad51 to nuclear foci after exposure to UV or treatment with ionizing radiation (IR). The data show that either phosphorylation of Rad51 by Chk1 or phosphorylation of the carboxy-terminal domain of hBRCA2 by Chk1 or Chk2 plays a critical role in the binding of Rad51 to hBRCA2 and the subsequent recruitment of Rad51 to sites of DNA damage. While depletion of Chk1 from cells leads to loss of Rad51 localization to nuclear foci in response to replication arrest, cells lacking Chk2 also show a defect in Rad51 localization, but only in presence of double strand DNA breaks, indicating that each of these kinases may contribute somewhat differently to the formation of Rad51 nucleoprotein filaments depending on the type of DNA damage incurred by the cells.

Autometallographic tracing of zinc ions in growing bone.

It has previously been established that zinc (Zn) supplementation increases bone dimensions and strength in growing rats. The present study aims at describing differences in the localization of loosely bound or free zinc ions, as revealed by autometallography (AMG), that might take place in the skeleton of growing rats following alimentary zinc depletion and supplementation. Male Wistar rats, 4 weeks old, were randomly divided into three groups. The rats had free access to a semi-synthetic diet with different amounts of zinc added. Group 1 was given a zinc-free (2 mg zinc/kg) diet, group 2 a 47 mg zinc/kg diet, and group 3 a 60 mg zinc/kg diet. All animals were killed after 4 weeks. Animals from each group were transcardially perfused with a 0.1 % sodium sulphide solution according to the zinc specific Neo-Timm method causing zinc ions to be bound in AMG catalytic zinc-sulphur clusters. We found clusters of zinc ions localized in the mineralizing osteoid in all groups. No immediate differences in AMG staining intensity could be observed between the groups neither in the uncalcified bone nor in the osteoblasts. However, alimentary zinc supply resulted in an increase in the height of the total growth plate in a dose-dependent manner. Zinc ions were also observed in chondrocytes throughout the whole thickness of the articular and the epiphyseal cartilage as well as in the inner layer of the synovial membrane.

The positive effects of zinc on skeletal strength in growing rats.

The aim of the present study was to assess the skeletal effects of alimentary zinc depletion and supplementation in an animal model of intact, growing rats. The study was planned as a dose-response study. Thirty-six male Wistar rats, 4 weeks old, were divided into three groups of 12 rats each. The rats had free access to a semisynthetic diet with different amounts of zinc added. Group 1 was given a zinc-free diet containing 2 mg zinc/kg, group 2 was given a normal-zinc diet containing 47 mg zinc/kg; and group 3 was given a zinc-supplemented diet containing 60 mg zinc/kg. All animals were killed 4 weeks after initiation of the experiment and the right femora were removed. The biomechanical effects were measured at the following skeletal sites: femoral diaphysis; femoral neck; and distal femoral metaphysis. In addition, static histomorphometry was performed at the middiaphyseal region. Biomechanical testing revealed a significant zinc-induced increase in bone strength at all sites investigated. It also showed that zinc influenced bone strength in a dose-dependent manner except at the distal metaphysis, where there was no significant difference between the group fed normal-zinc diet and the group fed a hyper-zinc diet. Zinc also improved the rates of growth in the rats. The body weights and length of femora increased dose-dependently. Static histomorphometry showed that zinc exerted its main effect on the periosteal envelope, thereby increasing bone area, tissue area, and axial moment of inertia. We conclude that alimentary zinc supplementation in growing rats induces an increase of bone strength in both the femoral neck and the femoral diaphysis. These results further support the view that zinc has a positive effect on bone metabolism which mimics that of growth hormone (GH) or insulin-like growth factor 1 (IGF-1).

[Rupture of the symphysis after spontaneous delivery. Surgical treatment of four cases]. / Symfyseruptur opstået i forbindelse med spontan fødsel. Operativ behandling i fire tilfaelde.

Rupture of the symphysis pubis is a rare, but known, complication during labour. We describe four cases of rupture of the symphysis, for which surgical treatment was chosen shortly after labour (2-30 days). Internal fixation was done in two cases and external fixation in the other two. There were no postoperative complications. The patients were mobile soon after the operation, and had no pain and normal function at follow-up 6-12 months later.

Efficacy and tolerability of lornoxicam versus tramadol in postoperative pain.

This randomized double-blind study compared the analgesic efficacy and tolerability of intramuscular lornoxicam and tramadol in 76 patients with moderate to unbearable pain following arthroscopic reconstruction of the anterior cruciate ligament using the patella bone-tendon-bone technique. Patients receiving a single dose of lornoxicam 16 mg experienced significantly greater total pain relief than patients receiving tramadol 100 mg over the following 8 hours. Lornoxicam had greater analgesic efficacy than tramadol in patients with moderate baseline pain but was of equivalent efficacy in those with severe/unbearable baseline pain. Fewer patients in the lornoxicam group required rescue medication (58% vs. 77%, respectively). Patients' global impression of efficacy showed lornoxicam to be superior to tramadol with 82% and 49% of patients, respectively, rating treatment as good, very good, or excellent. Following multiple-dose administration of lornoxicam (8 mg tid) or tramadol (100 mg tid) for 3 days, efficacy profiles similar to those following a single dose were obtained. Thus, slightly fewer patients in the lornoxicam group required rescue medication, and patients' global impression of efficacy again favored lornoxicam. Adverse events were reported by 38 of the 76 patients and were mainly mild to moderate in severity. Significantly fewer patients reported one or more adverse events with lornoxicam than with tramadol (14 vs. 24, respectively). Thus, intramuscular lornoxicam offers a useful alternative to tramadol for the treatment of moderate to severe postoperative pain.

[Psoas abscess in pyogenic sacroiliitis]. / Psoasabsces ved pyogen sacroiliitis.

A 47-year-old man was admitted with septic fever over a few days. A CT-scan showed a psoas abscess, which was drained by surgery. In the meantime antibiotics were started. In spite of this treatment, he continued to have septic fever. Bone scintigraphy and MR-scan showed activity in the right sacroiliac joint compatible with sacroiliitis. The joint was opened surgically and revised. The patient was treated with antibiotics for nine weeks and was fully restituted. It must be concluded that the psoas abscess was secondary to the sacroiliitis, a rare event.

[Multiple fractures following seizures in a pregnant woman]. / Multiple frakturer opstået under krampeanfald hos en gravid kvinde.

A 27-year-old woman, immigrated from Libanon, pregnant and at term was admitted with pain in the lower abdomen. The history was badly recognized because of the patient's inability to speak Danish. X-ray revealed a fracture of the left acetabulum with a minor central dislocation of the femoral head. During a new seizure she had another fracture of the right acetabulum also with a minor central dislocation of the femoral head and an undisplaced fracture of the proximal humerus on the left side. She was then delivered by a caesarean section. The seizures were later found to be due to grand mal type epileptic attacks. This case underlines the importance of a careful clinical and radiological investigation of patients with complaints of pain related to the central joints after seizures.

Airway dimensions and head posture in obstructive sleep apnoea.

The present cephalometric study aimed to describe the antero-posterior diameters of the pharyngeal airway in a sample of 50 male obstructive sleep apnoea (OSA) patients and a reference sample of 103 male students, and to examine the relationship between these diameters and the posture of the head and the cervical column. Subjects were recorded in the cephalometer standing with the head in its natural position (mirror position). Pharyngeal airway diameters were measured at seven levels ranging from the maxillary tuberosity to the vallecula of the epiglottis. The largest difference was observed at the level behind the soft palate where the diameter was 50 per cent narrower in the OSA sample than in the reference sample. Extension of the cranio-cervical angle and forward inclination of the cervical column were correlated with an increase in the three most caudal airway diameters in the OSA sample: at the uvula, the root of the tongue, and the epiglottis, but only to increase in the lowest diameter in the reference sample. The findings were considered to reflect a compensatory physiological postural mechanism that serves to maintain airway adequacy in OSA patients in the awake erect posture, most efficiently so at the lowest levels of the oropharyngeal airway.

Intrathoracic pressure variations in obese habitual snorers.

Six obese patients with complaints of snoring and daytime fatigue were monitored with polysomnography (PSG) and continuous recording of esophageal pressure (Pes) during 1 night. Nonapneic episodes in different sleep stages, with and without snoring, were selected and analysed. Peak to peak pressure was found to be significantly increased during snoring in sleep stages 2 and 3/4 with blood gas variations within the limits of normal unobstructed breathing, indicating increased respiratory effort. The present investigation supports the assumption that daytime tiredness in nonapneic patients can be linked to increased respiratory effort during sleep and that continuous esophageal pressure measuring may contribute to assessment of this condition.

Head posture in obstructive sleep apnoea.

In growing subjects, obstruction of the upper airway may lead to excessive vertical facial development. According to the soft-tissue stretching hypothesis (Solow and Kreiborg, 1977) this could be due to an increased cranio-cervical angulation triggered by the airway obstruction. The present study aimed to examine the effect of airway obstruction on cranio-cervical posture in a sample of adult patients with severe obstructive sleep apnoea (OSA). Lateral cephalometric radiographs taken in the natural head position (mirror position) were obtained from 50 male patients aged 28-70 with polysomnographic diagnosis of obstructive sleep apnoea. The Apnoea Index ranged from 21 to 98 episodes per hour with a mean of 54.6. Control samples were available from previous cephalometric studies of head posture in five samples of healthy subjects and one sample of congenitally blind subjects. The average cranio-cervical angle, NSL/OPT, was found to be extremely large (mean 104.1, SD 9.1) exceeding the average values in the control samples by 1-2 standard deviations (P < 0.001). It is suggested that the large cranio-cervical angle in OSA patients is a physiological adaptation aiming to maintain airway adequacy while the head, and thus the visual axis, is kept in its natural relationship to the true vertical. The findings thus provide evidence for the hypothesis that upper airway obstruction may trigger an increase in the cranio-cervical angulation.

Computerized apnea detection in ambulatory sleep recording with the Somnolog system.

Apnea detection from a traditional polysomnographic sleep recording is tedious and time consuming. With a new portable device, the Somnolog, it is possible to make ambulatory sleep recording and apnea detection.

Bilateral facial palsy caused by the Borrelia spirochete.

A case of total left peripheral and partial right peripheral facial palsy caused by the Borrelia spirochete is presented. The diagnosis was confirmed by the history of the tick-bites and elevated titers of IgG in serum and cerebrospinal fluid.

Alternative treatment of obstructive sleep apnea: nasal-CPAP continuous positive airway pressure.

The upper airway of patients with obstructive sleep apnea is often characterised by a narrow lumen and increased compliance of the pharyngeal wall. During inspiration, a negative inspiratory pressure is developed which may produce occlusion in the pharynx. Continuous positive airway pressure (CPAP) works as a pneumatic splint dilating the upper airway and thus keeping the airway open. The result is a patent airway, free regular breathing during sleep with no oxygen desaturations and normal sleep architecture. Irregular pulse, fluctuations in blood pressure, increased levels of catecholamines recorded during sleep in patients with obstructive sleep apnea are normalised during CPAP treatment.

Shortened reaction time during nasal CPAP treatment of obstructive sleep apnea.

In 5 patients with severe obstructive sleep apnea the effect of nasal continuous positive airway pressure (CPAP) treatment on daytime functioning was measured. During a 2-week period, when the patients were effectively treated with nasal CPAP, a shortening of the reaction time could be measured.

[Obstructive sleep apnea treated with uvulo-palato-pharyngoplasty]. / Obstruktiv søvnapnø behandlet med uvulopalatofaryngoplastik.

Uvulo-palato-pharyngo-plasty (UPPP) was introduced as a method of treatment of obstructive sleep apnoea in 1980. The pathogenesis of obstructive sleep apnoea is described. The operative technique is also described and illustrative case histories are quoted. The effect obtained varies and, for this reason, the role of UPPP in the treatment of obstructive sleep apnoea cannot be finally established.

[Anesthesia for single-day orthopedic surgery]. / Anaestesi til ortopaedkirurgisk endagskirurgi.

During the period 1 January 1989 to 31 December 1989, a total of 1,004 patients were submitted to outpatient single-day surgery in Aalborg Hospital. As fas as possible, the patients were anaesthetized with propofol (Diprivan)/alfentanil (Rapifen) and oxygen and atmospheric air. This form of anaesthesia was found to be rapid and suitable for single-day surgery. 8.1% of the patients required admission for further observation, 2.3% of these on account of anaesthesiological complications. It is concluded that, by means of meticulous planning, it is possible to carry out ambulant anaesthesia and surgery and, employing limited staff resources, it has proved possible to reduce the waiting time for outpatient intervention to 10-12 weeks.