Uwe Rehder

Organization and morphogenesis of the human seminiferous epithelium

SummaryThe various types of human primary spermatocytes were classified by means of morphological and morphometrical studies. Based on this classification, the topographic arrangement of the spermatocyte populations in the longitudinal course of seminiferous tubules was determined. This analysis revealed human spermatogenesis be to subjected to a complex local plan of organization, which is based upon the geometry of spirals.The centers of gravity of spermatocyte populations of subsequent degrees of differentiation are arranged on he lices that are contracted conically to the lumen of the seminiferous tubule. On these helices the centers of gravity of the populations diverge continuously 173.8°+/-32.4°. Populations of the same degrees of development are arranged on helices with constant diameters. On these helices the centers of gravity of the populations diverge continuously 142.6°+/-14.2°.The present results lead to new aspects of the kinetics and morphogenesis of the seminiferous epithelium, which can be integrated into a comprehensive biological concept.

Cohort study of occupational risk factors of low back pain in construction workers.

OBJECTIVES To identify work related risk factors of future low back pain (LBP) in a cohort of construction workers free of LBP at the start of follow up. METHODS The Hamburg construction worker study comprises 571 male construction workers who have undergone two comprehensive interview and physical examination surveys. A cohort of 285 subjects without LBP at baseline was identified. After a follow up of 3 years, the 1 year prevalence of self reported LBP was determined in the 230 men followed up (80.7%). Prevalence ratios (PRs) with 95% confidence intervals (95% CIs) of LBP at follow up according to self reported work tasks of construction workers measured at baseline were estimated from Coxs regression models which were adjusted for age, and anthropometric measures. RESULTS At follow up 71 out of 230 workers (30.9%) reported LBP during the preceding 12 months. Four work tasks (scaffolding, erecting roof structures, sawing wood, laying large sandstones) with an increased risk of 1 year prevalence of LBP at follow up were further evaluated. After further adjustment for occupation the relative risk was increased for workers who had reported ⩾2 hour/shifts laying large sandstones (PR=2.6; 95% CI 1.1 to 6.5). Work load of bricklayers was additionally estimated by an index on stone load (high exposure: PR=4.0; 95% CI 0.8 to 19.8), and an index for laying huge bricks/blocks (yes/no: PR=1.7; 95% CI 0.5 to 5.7). CONCLUSIONS The results suggest that self reported differences in brick characteristics (size and type of stone) and temporal aspects of the work of bricklayers (average hours per shift laying specified stones) can predict the future prevalence of LBP. The data have to be interpreted with caution because multiple risk factors were tested.

The Spectrum of Syndromes and Manifestations in Individuals Screened for Suspected Marfan Syndrome

The diagnosis of Marfan syndrome (MFS) is based on evaluating a large number of clinical criteria. We have observed that many persons presenting in specialized centers for “Marfan‐like” features do not have MFS, but exhibit a large spectrum of other syndromes. The spectrum of these syndromes and the distribution of “Marfan‐like” features remain to be characterized. Thus, we prospectively evaluated 279 consecutive patients with suspected MFS (144 men and 135 women at a mean age of 34 ± 13 years) for presence of 27 clinical criteria considered characteristic of MFS. The most frequent reasons to refer individuals for suspected MFS were skeletal features (31%), a family history of MFS, or aortic complications (29%), aortic dissection or aneurysm (19%), and eye manifestations (9%). Using established criteria, we confirmed MFS in 138 individuals (group 1) and diagnosed other connective tissue diseases, both with vascular involvement in 30 (group 2) and without vascular involvement in 39 (group 3), and excluded any distinct disease in 72 individuals (group 4). Clinical manifestations of MFS were present in all four patient groups and there was no single clinical criterion that exhibited positive and negative likelihood ratios that were per se sufficient to confirm or rule out MFS. We conclude that “Marfan‐like” features are not exclusively indicative of MFS but also of numerous, alternative inherited diseases with many of them carrying a hitherto poorly defined cardiovascular risk. These alternative diseases require future study to characterize their responses to therapy and long‐term prognosis.

Computer-aided three-dimensional reconstructions of the arrangement of primary spermatocytes in human seminiferous tubules.

SummaryWith the use of a digital image-processing method three-dimensional reconstructions of the arrangement of spermatocytes in human seminiferous tubules were performed. With this method it was possible to investigate the cellular distribution in the tubule in nearly any given perspective and projection. In addition, by means of simple mathematical procedures, such as by transformation of Cartesian coordinates into cylindrical coordinates, it was possible to vary the shape of a reconstruction, i.e., to convert the cylindrical image of a tubular portion into a right-angled r-ϕ-z-representation.The present work not only confirms the existence of a complex helical plan of organization of the human seminiferous epithelium but also provides further aspects of the phenomenon of physiological germ-cell loss and its integration into the kinetics of spermatogenesis.

Sacroiliac dysfunction in construction workers

BACKGROUND In the literature of manual medicine the sacroiliac joint is widely accepted as a potential source of low back pain. On the other hand, some investigations have detected sacroiliac joint dysfunction without concomitant low back pain. The prevalence of sacroiliac dysfunction in the population has been noted in the medical literature to be between 19.3% and 47.9%. However, the prevalence of sacroiliac dysfunction in the general population and for construction workers is unknown. OBJECTIVE This article presents results from the Hamburg Construction Workers Study in respect to sacroiliac diagnostics. The prevalence of and connection between sacroiliac dysfunction and low back pain are particularly interesting. DESIGN AND PARTICIPANTS The sacroiliac joint diagnostics were studied in a cross-section investigation of a cohort of 480 male construction workers. Manual examination is the standard in the diagnostics of sacroiliac joint conditions at present. The assessment of sacroiliac joint function by standing flexion test, the spine test, the iliac compression test, and the iliac springing test was operationalized as two categories: sacroiliac dysfunction I and II. RESULTS A prevalence of 29.0% was found for dysfunction I and 6.3% for dysfunction II, whereas a prevalence of 7.9% was found for the coprevalence of low back pain and sacroiliac dysfunction on the day of examination. This study demonstrated no statistical associations between low back pain and sacroiliac joint dysfunction. CONCLUSIONS The reason why symptomatic and asymptomatic sacroiliac dysfunctions exist has not yet been sufficiently explained. The identification of pain-provoking factors should be the aim of subsequent investigations. A further study with a prospective design will be necessary to answer the questions that remain.

Sacroiliac joint diagnostics in the Hamburg Construction Workers Study

BACKGROUND In the medical literature, test procedures for sacroiliac joint diagnostics are viewed as controversial. The provocation tests are based on provoked sacroiliac pain, whereas the palpation tests examine the motion of the sacroiliac joint or describe the condition indirectly if limitation of the sacroiliac function is present. It must be presumed that the use of different test results in the detection of varying functional phenomena of a sacroiliac dysfunction or, alternatively, that identical effects of a dysfunction are evaluated in differing ways. OBJECTIVE This article presents results with regard to the consistency of tests for sacroiliac joint dysfunctions carried out on participants from the building trade. DESIGN AND PARTICIPANTS The consistency of the tests (standing flexion test, spine test, iliac compression test, iliac springing test) used in a cross-section investigation of a cohort of 480 male construction workers is presented. To evaluate the degree of consistency of the test procedure the percentage agreement and the kappa value, including a confidence interval of 95%, are given. RESULTS The consistency between the iliac compression test and the three sacroiliac palpation tests could not be shown to be statistically significant. The consistency between the three palpation tests was moderate to good and the percentage agreement was acceptable (87.4%, 88.6%, 80.9%). CONCLUSIONS It may be assumed that the palpation tests characterize the same dysfunction of the sacroiliac joint. Standing flexion test, spine test, and iliac springing test seem to be valuable tools for sacroiliac joint diagnostics.

Bilateral osteochondritis dissecans of the medial trochlea femoris: an unusual case of patellofemoral pain

We report a case of bilateral osteochondritis dissecans of the medial trochlea femoris. Arthroscopic removement of loose bodies in the symptomatic left knee led to an excellent result; the untreated right knee showed effusion and locking one year later. This condition should be considered in the diagnosis of patellofemoral pain.

Morbus de Anquin or spinous engagement syndrome. A rare cause of low-back pain syndrome and sciatica.

SummaryWe report on a rare disease called to Anquins disease or spinous engagement or impingement syndrome. Low-back pain in this specific syndrome probably combined with sciatica is caused by a hypertrophic spinous process along with a spina bifida occulta of the underlying vertebra. Mostly, the enlarged spinous process is seen at L5 and the spina bifida occulta at S I. Conservative therapy consists of physiotherapy with postural exercises including improvement of lumbar flexion. If conservative treatment is unsuccessful, surgical treatment is indicated. Surgical therapy should include resection of the hypertrophic spinous process, probably combined with revision of the nerve roots and division of adhesions. Between 1981 and 1993 six patients were treated surgically after long-lasting periods of conservative therapy. All patients were re-examined clinically and radiologically after a mean follow-up period of 2.9 years. In all but one patient a distinct release from lumbar back pain and/or sciatica was observed. Regarding this, the most important fact in de Anquins disease is to be aware of this specific syndrome. If low-back pain can be traced to a hypertrophic spinous process the first choice of therapy should be conservative. In unsuccessful cases simple surgical resection probably combined with division of the adhesion can lead to significant release from pain and is recommended.

Analyse der Erlössituation bei der ambulanten Behandlung nach § 116 b SGB V am Beispiel des Marfan-Syndroms

ZusammenfassungHintergrund:Das Marfan-Syndrom ist eine typische Seltene Erkrankung mit Multisystembeteiligung und Erfordernis der spezialisierten medizinischen Versorgung. Die Richtlinie über die ambulante Behandlung im Krankenhaus nach § 116 b SGB V soll durch verbesserte Vergütungsmöglichkeiten eine hochwertige medizinische Versorgung in Klinikambulanzen ermöglichen. Die Autoren legen die erste Auswertung einer Kosten- und Erlösrechnung in der ambulanten Versorgung von Marfan-Patienten nach § 116 b vor.Methodik:Innerhalb 1 Jahres wurden 184 Fälle entsprechend § 116 b versorgt. Die Autoren ermittelten die Kosten der medizinischen Leistungen entsprechend der internen Leistungsverrechnung auf Basis des Hauskatalogs ihrer Klinik. Die Erlöse ermittelten sie zum einen nach den Vorgaben des § 116 b [Erlöse(§116b)] und zum anderen entsprechend der Pauschale für Hochschulambulanzen gemäß § 117 SGB V [Erlöse(§117)].Ergebnisse:In 117 Fällen (64%) reisten die Patienten aus < 50 km, in 27 Fällen (15%) aus ≥ 50 bis ≤ 100 km und in 40 Fällen (22%) aus > 100 km Entfernung von der Klinik an. Die Kosten der medizinischen Leistungen lagen bei insgesamt 71 606,28 Euro. Die Erlöse(§116b) betrugen demgegenüber insgesamt 55 549,87 Euro und die Erlöse(§117) 11 776,00 Euro, womit eine Unterdeckung von 16 056,41 Euro bei Abrechnung nach § 116 b (22%) bzw. von 59 830,28 Euro bei Abrechnung nach § 117 (84%) vorlag.Schlussfolgerung:Die teilweise lange Anreise zu spezialisierten Zentren wird offenbar zugunsten verbesserter medizinischer Versorgung in Kauf genommen. Zentralisierte ambulante Versorgung erfordert jedoch eine gute Vernetzung mit wohnortnahen medizinischen Leistungserbringern. Die Abrechnung medizinischer Leistungen nach § 116 b hat trotz 22%iger Unterdeckung der Kosten zu einer deutlichen Verbesserung der Erlössituation geführt. Die Qualität der medizinischen Versorgung konnte dadurch gebessert werden.AbstractBackground:The Marfan syndrome is a typical rare disease with multiorgan involvement and the need for specialized interdisciplinary medical care. A novel German legal directive according to section sign 116 b of the Social Statutes Book V (§ 116 b SGB V) improves options for reimbursement and thus encourages specialized hospitals to provide ambulatory care for rare diseases such as Marfan syndrome. The authors provide the first economic analysis of § 116 b in a German Marfan center.Methods:The costs were assessed in 184 cases with Marfan syndrome receiving medical care in the Hamburg Marfan Clinic. The authors assessed the financial profit both according to payments received from invoices established according to the § 116 b directive [reimbursement(§116b)] and from calculations according to § 117 SGB V [reimbursement (§117)].Results:A total of 117 patients traveled to the Marfan clinic (64%) < 50 km, 27 patients (15%) between ≥ 50 and ≤ 100 km, and 40 patients (22%) > 100 km. The total costs for ambulatory care were 71,606.28 Euros. The reimbursement(§116b) was 55,549.87 Euros and the reimbursement(§117) was 11,776.00 Euros.Conclusion:Many patients accept long distances of traveling to receive specialized ambulatory medical care. However, for optimal patient management specialized centers need to cooperate intensively with local health care providers. The novel legal directive according to § 116 b has significantly improved reimbursement for Marfan centers and allows for improving the quality of medical care.BACKGROUND The Marfan syndrome is a typical rare disease with multiorgan involvement and the need for specialized interdisciplinary medical care. A novel German legal directive according to section sign 116 b of the Social Statutes Book V (116 b SGB V) improves options for reimbursement and thus encourages specialized hospitals to provide ambulatory care for rare diseases such as Marfan syndrome. The authors provide the first economic analysis of section sign 116 b in a German Marfan center. METHODS The costs were assessed in 184 cases with Marfan syndrome receiving medical care in the Hamburg Marfan Clinic. The authors assessed the financial profit both according to payments received from invoices established according to the 116 b directive [reimbursement (116b)] and from calculations according to section sign 117 SGB V [reimbursement (117)]. RESULTS A total of 117 patients traveled to the Marfan clinic (64%) < 50 km, 27 patients (15%) between >or= 50 and <or= 100 km, and 40 patients (22%) > 100 km. The total costs for ambulatory care were 71,606.28 Euro. The reimbursement (116b) was 55,549.87 Euro and the reimbursement (117) was 11,776.00 Euro. CONCLUSION Many patients accept long distances of traveling to receive specialized ambulatory medical care. However, for optimal patient management specialized centers need to cooperate intensively with local health care providers. The novel legal directive according to section sign 116 b has significantly improved reimbursement for Marfan centers and allows for improving the quality of medical care.

Analyse der Erlössituation bei der ambulanten Behandlung nach § 116 b SGB V am Beispiel des Marfan-Syndroms@@@Analysis of Costs and Profits of Ambulatory Care of Marfan Patients after Initiation of a Novel German Legal Directive (§ 116 b SGB V)

ZusammenfassungHintergrund:Das Marfan-Syndrom ist eine typische Seltene Erkrankung mit Multisystembeteiligung und Erfordernis der spezialisierten medizinischen Versorgung. Die Richtlinie über die ambulante Behandlung im Krankenhaus nach § 116 b SGB V soll durch verbesserte Vergütungsmöglichkeiten eine hochwertige medizinische Versorgung in Klinikambulanzen ermöglichen. Die Autoren legen die erste Auswertung einer Kosten- und Erlösrechnung in der ambulanten Versorgung von Marfan-Patienten nach § 116 b vor.Methodik:Innerhalb 1 Jahres wurden 184 Fälle entsprechend § 116 b versorgt. Die Autoren ermittelten die Kosten der medizinischen Leistungen entsprechend der internen Leistungsverrechnung auf Basis des Hauskatalogs ihrer Klinik. Die Erlöse ermittelten sie zum einen nach den Vorgaben des § 116 b [Erlöse(§116b)] und zum anderen entsprechend der Pauschale für Hochschulambulanzen gemäß § 117 SGB V [Erlöse(§117)].Ergebnisse:In 117 Fällen (64%) reisten die Patienten aus < 50 km, in 27 Fällen (15%) aus ≥ 50 bis ≤ 100 km und in 40 Fällen (22%) aus > 100 km Entfernung von der Klinik an. Die Kosten der medizinischen Leistungen lagen bei insgesamt 71 606,28 Euro. Die Erlöse(§116b) betrugen demgegenüber insgesamt 55 549,87 Euro und die Erlöse(§117) 11 776,00 Euro, womit eine Unterdeckung von 16 056,41 Euro bei Abrechnung nach § 116 b (22%) bzw. von 59 830,28 Euro bei Abrechnung nach § 117 (84%) vorlag.Schlussfolgerung:Die teilweise lange Anreise zu spezialisierten Zentren wird offenbar zugunsten verbesserter medizinischer Versorgung in Kauf genommen. Zentralisierte ambulante Versorgung erfordert jedoch eine gute Vernetzung mit wohnortnahen medizinischen Leistungserbringern. Die Abrechnung medizinischer Leistungen nach § 116 b hat trotz 22%iger Unterdeckung der Kosten zu einer deutlichen Verbesserung der Erlössituation geführt. Die Qualität der medizinischen Versorgung konnte dadurch gebessert werden.AbstractBackground:The Marfan syndrome is a typical rare disease with multiorgan involvement and the need for specialized interdisciplinary medical care. A novel German legal directive according to section sign 116 b of the Social Statutes Book V (§ 116 b SGB V) improves options for reimbursement and thus encourages specialized hospitals to provide ambulatory care for rare diseases such as Marfan syndrome. The authors provide the first economic analysis of § 116 b in a German Marfan center.Methods:The costs were assessed in 184 cases with Marfan syndrome receiving medical care in the Hamburg Marfan Clinic. The authors assessed the financial profit both according to payments received from invoices established according to the § 116 b directive [reimbursement(§116b)] and from calculations according to § 117 SGB V [reimbursement (§117)].Results:A total of 117 patients traveled to the Marfan clinic (64%) < 50 km, 27 patients (15%) between ≥ 50 and ≤ 100 km, and 40 patients (22%) > 100 km. The total costs for ambulatory care were 71,606.28 Euros. The reimbursement(§116b) was 55,549.87 Euros and the reimbursement(§117) was 11,776.00 Euros.Conclusion:Many patients accept long distances of traveling to receive specialized ambulatory medical care. However, for optimal patient management specialized centers need to cooperate intensively with local health care providers. The novel legal directive according to § 116 b has significantly improved reimbursement for Marfan centers and allows for improving the quality of medical care.BACKGROUND The Marfan syndrome is a typical rare disease with multiorgan involvement and the need for specialized interdisciplinary medical care. A novel German legal directive according to section sign 116 b of the Social Statutes Book V (116 b SGB V) improves options for reimbursement and thus encourages specialized hospitals to provide ambulatory care for rare diseases such as Marfan syndrome. The authors provide the first economic analysis of section sign 116 b in a German Marfan center. METHODS The costs were assessed in 184 cases with Marfan syndrome receiving medical care in the Hamburg Marfan Clinic. The authors assessed the financial profit both according to payments received from invoices established according to the 116 b directive [reimbursement (116b)] and from calculations according to section sign 117 SGB V [reimbursement (117)]. RESULTS A total of 117 patients traveled to the Marfan clinic (64%) < 50 km, 27 patients (15%) between >or= 50 and <or= 100 km, and 40 patients (22%) > 100 km. The total costs for ambulatory care were 71,606.28 Euro. The reimbursement (116b) was 55,549.87 Euro and the reimbursement (117) was 11,776.00 Euro. CONCLUSION Many patients accept long distances of traveling to receive specialized ambulatory medical care. However, for optimal patient management specialized centers need to cooperate intensively with local health care providers. The novel legal directive according to section sign 116 b has significantly improved reimbursement for Marfan centers and allows for improving the quality of medical care.