[Osteoporosis: long-term treatment versus drug holiday-what is the evidence?] / Osteoporose: Dauertherapie versus Therapiepause ­ Wofür gibt es Evidenz?

The occurrence of multiple vertebral fractures after discontinuation of denosumab in the treatment of osteoporosis has reopened the debate on the optimal treatment duration and drug holidays.In principle, there is a difference in this regard between the discontinuation of medications such as bisphosphonates and substances without bone retention such as selective estrogen receptor modulators (SERMs), denosumab or teriparatide. Even after the end of application bisphosphonates have a very long half-life in the bones. After cessation of drug intake there is a slow, slight increase of bone turnover markers. Even after cessation of the SERM raloxifene, a decline in bone density can be observed, as with the termination of teriparatide. In contrast to these osteoporosis medications, after cessation of denosumab, a steep and rapid increase in markers of bone resorption above baseline levels ("rebound") and a reduction in bone mineral density to initial values can be observed.Osteoporosis is a disease that carries an increased risk of fracture, which is reduced for the duration of osteoporosis treatment. In certain situations, the fracture risk is only temporarily raised. In these situations, cessation of the osteoporosis treatment is possible. Beyond these special clinical situations, however, osteoporosis needs to be addressed as a chronic disease with a permanently increased fracture risk and the indication for therapy should be evaluated according to the extent of the risk of fracture.What happens after discontinuation of anti-osteoporosis drugs? The various effects on bone turnover markers, bone mineral density and fracture incidence of the individual drug groups are presented in detail, as are the resulting recommendations of the task forces of the American Society of Bone and Mineral Research (ASBMR) and the European Calcified Tissue Society (ECTS).

[Value of arthro-CT in decision for arthroscopic or open stabilization in ventral shoulder instability]. / Wertigkeit der Arthro-CT in der Entscheidung zur arthroskopischen oder offenen Stabilisierung bei ventraler Schulterinstabilität.

A prospective study was performed on 30 patients with anterior instability of the shoulder to assess the diagnostic value of preoperative arthro-CT. One special diagnostic problem was the definition of diagnostic criteria for arthroscopic or open surgery. Arthro-CT of the shoulder was performed with a double-contrast technique. Visualization of labral tears, bony lesions, glenohumeral ligaments and disruption of the rotator cuff was registered. Findings of arthro-CT were verified by diagnostic arthroscopy. Therapy consisted of either arthroscopic or open surgery depending on the lesion pattern found in diagnostic arthroscopy. The most common cause of anterior instability (90% of cases) was damage of the ventro-caudal labral complex, which was diagnosed by arthro-CT with a sensitivity of 93% and a positive predictive value of 93%. Specificity and negative predictive value were reduced to 33%; the overall accuracy was 87%. In all, 16 patients were successfully treated using arthroscopic stabilization because whereas 14 patients required open surgery because diagnostic arthroscopy contraindicated an arthroscopic approach. The preoperative arthro-CT failed to define all criteria mandatory for the decision for arthroscopic or open surgery because pathoanatomy of the joint was not sufficiently demonstrated with the current technique of arthro-CT.

[Clinical value of conventional radiology and MRI in assessing osteochondrosis dissecans stability]. / Der klinische Wert der konventionellen Radiologie und der MRT in der Stabilitätsbeurteilung der Osteochondrosis dissecans.

A prospective study was performed on 72 patients with osteochondritis dissecans (OD) of the knee and ankle to compare plane radiography, MRI and arthroscopy before therapeutic procedures. Special interest was placed on the assessment of fragment stability with radiological methods for staging related therapy. OD was localized in 46 cases on the femoral condyle and in 26 cases on the talus. Radiological methods were performed simultaneously and shortly before definite arthroscopical therapy. Using conventional radiography, OD of the condyles was staged according to the classification of Rodegerdts and Gleissner and OD of the talus suggested by Berndt and Harty. MRI staging was performed by morphology of the interface of the OD. Arthroscopical staging based on the classification of Guhl. There was an excellent correlation between the stages in MRI and arthroscopy, showing correct prediction of stable and unstable fragments in 92%. In contrast, fragment stability could not be efficiently assessed by conventional radiology because fragments could be stably fixed in cases of bony separation. MRI is indicated before performance of staging-related therapy of OD to select patients with stable fragments for conservative therapy and those with unstable OD for surgical therapy.

[Traumatic hemarthrosis of the knee joint--clinical significance of nuclear magnetic resonance tomography]. / Der traumatische Kniegelenkhämarthros--klinische Bedeutung der Kernspintomographie.

A prospective study was performed on 94 patients with hemarthrosis of the knee to assess the value of MR imaging (MRI) in detection of bleeding sources and selection of therapy modalities. Patients were examined clinically within a week after knee trauma; the investigations performed included puncture of the joint to confirm hemarthrosis, a conventional X-ray to exclude fractures, MRI and arthroscopy. MRI was performed for diagnosis of acute lesions, definition of bleeding sources by morphological criteria, and allocation of patients to conservative or surgical therapy. Arthroscopy was performed to control MRI, to visualize bleeding sources, and to maintain therapy if necessary. The 94 patients were found on arthroscopy to have a total of 123 bleeding sources, which were correctly defined by MRI in each of 107 cases as an acute lesion communicating with the joint space; 16 bleeding sources were not found and there were 10 false-positive reports. In keeping with our treatment strategies, arthroscopy disclosed lesions requiring surgical therapy in 77 of 94 patients (82%) and lesions that would be adequately treated by conservative therapy in 17 of 94 patients (18%). MRI predicted surgical or conservative therapy correctly before arthroscopy in 83 of 94 patients (88%). In conclusion, MRI has a high predictive value in definition of acute lesions that will lead to hemarthrosis of the knee. This noninvasive method allows screening out of the relatively small portion of patients without severe lesions, who then do not have to be subjected to further invasive therapy.

[MRT of the knee in the follow-up of the plastic repair of the anterior cruciate ligament with autologous semitendinosus tendon]. / MRT des Knies in der Verlaufskontrolle der vorderen Kreuzbandplastik aus autologer Semitendinosussehne.

In a prospective study, 153 MRI examinations were performed on 74 patients following reconstruction of a ruptured anterior cruciate ligament with a semitendinosus graft. MRI examinations were performed at three defined intervals (3 months, 4 to 12 months, and 1 to 2 years postoperatively), and the findings were compared to simultaneous clinical tests to define stability criteria. This permitted reliable assessment of the integrity of the ligament graft; in three cases we correctly diagnosed a ruptured graft. A well-defined tendon graft with recognizable fibrous structures correlated with a clinically stable ligament in 98% of the cases. Due to physiological transformation occurring from three months to one year postoperatively, that graft temporarily appears less distinct. Complete integration of the graft with full stability of the knee is visualized in the MRI scan as a tendon with low signal intensity. Postoperative complications and the desire to participate in sports activities are indications for MRI examination.

Effect of beta-adrenergic blockade on supramaximal exercise capacity.

Fourteen male physical education students performed a single bout of running until exhaustion on the treadmill at 22 km/h and 7.5% slope. They received single oral doses of 100 mg bupranolol (nonselective beta-blockade), 100 mg metoprolol (beta-1-selective blockade), and placebo 60-90 min before running. Arterialized capillary blood was sampled repeatedly until 30 min after exercise for assessment of lactate and glucose. Adrenaline and noradrenaline were determined in venous plasma before and immediately after exercise. Running time until exhaustion was 49.3 +/- 2.3 s in the control experiment, 44.5 +/- 2.0 s with metoprolol, and 42.7 +/- 2.0 s with bupranolol. The reductions under beta-blockade were statistically significant. With both beta-blockers the increases of the lactate and glucose blood levels were significantly reduced, the levels being almost identical with metoprolol and bupranolol. The post-exercise levels of adrenaline and noradrenaline did not differ significantly between the control, metoprolol, and bupranolol experiments. It is concluded that determination of the lactate and glucose levels in blood did not allow assessment of the mechanism by which beta-blockade impairs the capacity for supramaximal exercise. Besides reduced anaerobic energy release due to inhibition of glycogenolysis, other beta-blocker effects are considered.

Catecholamines, growth hormone, cortisol, insulin, and sex hormones in anaerobic and aerobic exercise.

Seventeen male physical education students performed three types of treadmill exercise: (1) progressive exercise to exhaustion, (2) prolonged exercise of 50 min duration at the anaerobic threshold of 4 mmol . l-1 blood lactate (AE), (3) a single bout of short-term high-intensity exercise at 156% of maximal exercise capacity in the progressive test, leading to exhaustion within 1.5 min (ANE). Immediately before and after ANE and before, during, and after AE adrenaline, noradrenaline, growth hormone, cortisol, insulin, testosterone, and oestradiol were determined in venous blood, and glucose and lactate were determined in arterialized blood from the earlobe. Adrenaline and noradrenaline increased 15 fold during ANE and 3--4 fold and 6--9 fold respectively during AE. The adrenaline/noradrenaline ratio was 1 : 3 during ANE and 1 : 10 during AE. Cortisol increased by 35% in ANE (12% of which appeared in the postexercise period) and 54% in AE. Insulin increased during ANE but decreased during AE. Testosterone and oestradiol increased by 14% and 16% during ANE and by 22% and 28% during AE. The results point to a markedly higher emotional stress and higher sympatho-adrenal activity in anaerobic exercise. Growth hormone and cortisol appear to be the more affected by intense prolonged exercise. Taking plasma volume changes and changes of metabolic clearance rates into consideration, neither of the exercise tests appeared to affect secretion of testosterone and oestradiol.