What is intervertebral disc degeneration, and what causes it?

STUDY DESIGN: Review and reinterpretation of existing literature. OBJECTIVE: To suggest how intervertebral disc degeneration might be distinguished from the physiologic processes of growth, aging, healing, and adaptive remodeling. SUMMARY OF BACKGROUND DATA: The research literature concerning disc degeneration is particularly diverse, and there are no accepted definitions to guide biomedical research, or medicolegal practice. DEFINITIONS: The process of disc degeneration is an aberrant, cell-mediated response to progressive structural failure. A degenerate disc is one with structural failure combined with accelerated or advanced signs of aging. Early degenerative changes should refer to accelerated age-related changes in a structurally intact disc. Degenerative disc disease should be applied to a degenerate disc that is also painful. JUSTIFICATION: Structural defects such as endplate fracture, radial fissures, and herniation are easily detected, unambiguous markers of impaired disc function. They are not inevitable with age and are more closely related to pain than any other feature of aging discs. Structural failure is irreversible because adult discs have limited healing potential. It also progresses by physical and biologic mechanisms, and, therefore, is a suitable marker for a degenerative process. Biologic progression occurs because structural failure uncouples the local mechanical environment of disc cells from the overall loading of the disc, so that disc cell responses can be inappropriate or "aberrant." Animal models confirm that cell-mediated changes always follow structural failure caused by trauma. This definition of disc degeneration simplifies the issue of causality: excessive mechanical loading disrupts a disc's structure and precipitates a cascade of cell-mediated responses, leading to further disruption. Underlying causes of disc degeneration include genetic inheritance, age, inadequate metabolite transport, and loading history, all of which can weaken discs to such an extent that structural failure occurs during the activities of daily living. The other closely related definitions help to distinguish between degenerate and injured discs, and between discs that are and are not painful.     

Patient satisfaction with anaesthesia care: what is patient satisfaction, how should it be measured, and what is the evidence for assuring high patient satisfaction?

Patient satisfaction is a part of outcome quality. Many theories of satisfaction include patients' expectation. One definition of satisfaction is therefore the degree of congruence between expectation and accomplishment. The involvement of patients as well as experts is therefore an important step in the development of an instrument to measure patient satisfaction. Results of single-item ratings or overall satisfaction surveys are over-optimistic and do not represent the true indication of care. The construction of highly standardized (psychometric) questionnaires should include elements of content validity, criterion and construct validity, reliability and practicability. Based on the few available studies in anaesthesia, patient satisfaction is primarily determined by information and communication. There is great potential for improvement in this area. However, we do not know the best way to continuously improve patient satisfaction with anaesthesia care, or to what extent decisions should be shared between the anaesthetist and the patient.     

"CF asthma": what is it and what do we do about it?

The diagnosis of "CF asthma" is problematic and it is difficult to determine which patients have a combination of CF and asthma and which have asthma like symptoms caused by inflammation of the CF lung. This may not matter, however; the relevance lies in the possible approaches to treatment.     

Restitution of the aortic valve: what is new, what is proven, and what is obsolete?

Restitution strategies of the insufficient aortic valve belong to the clinical armamentarium. To date, the accumulated body of evidence comprises 126 articles dealing with restitution strategies on the insufficient aortic valve with concomitant aortic surgery. In a cumulative analysis an almost identical number of reimplantation (506) and remodeling (489) procedures were found in the literature, whereas 357 patients underwent aortic valve resuspension. The cumulative results tend to favor the reimplantation technique in terms of longevity of the reconstruction, particularly in congenital degenerative disorders of the aortic wall, whereas remodeling appears to exhibit a more physiologic behavior of the reconstructed valve and re-suspension serves as a simplified approach particularly in acute type A dissection. Although restitution of the native aortic valve has its place in current treatment options, the accumulated worldwide numbers indicate that it is not yet routinely implemented in the vast majority of cardiac institutions.     

The Lund-Mackay staging system for chronic rhinosinusitis: how is it used and what does it predict?

OBJECTIVES: The Lund-Mackay score is widely used in assessment of chronic rhinosinusitis. We aimed to describe its relationship to other measures of pre- and post-treatment health status. STUDY DESIGN: Multicenter prospective study of 1840 patients undergoing surgery for chronic rhinosinusitis in the UK. RESULTS: There was no absolute threshold for surgery, but patients with higher Lund-Mackay scores underwent more extensive surgery. There was no correlation between Lund-Mackay and SNOT-22 scores. The Lund-Mackay increased with increasing grade of polyposis. The Lund-Mackay score was associated with symptom reduction (coefficient = 0.24, P = 0.02) complication rates (odds ratio, 1.08, 95%CI 1.06 to 1.1), and revision rates (odds ratio, 1.03, 95% CI 1.001 to 1.06). CONCLUSIONS: The Lund-Mackay score measures a different aspect of disease to "subjective" symptom scores. However, it correlates well with other markers of disease severity, the nature of surgery offered, and its outcome. SIGNIFICANCE: This demonstrates the strengths and limitations of a commonly used staging system.     

Information needs in operating room teams: what is right, what is wrong, and what is needed?

Background  

Safe surgical care requires effective information transfer between members of the operating room (OR) team. The present study aims to assess directly, systematically, and comprehensively, information needs of all OR team-members.     

Allocation of vascularized composite allografts: what is it?

To date, there are more than 80 reports of vascularized composite allografts (VCAs; a.k.a. composite tissue allotransplantation). However, the classification of this type of transplantation for oversight purposes has not been clarified. From a biological and regulatory perspective, we propose that VCA retrieval and transplantation is akin to organ transplantation and should be incorporated into the organ oversight structure. As VCA becomes more of a clinical reality, the need for a methodical approach to allocation and access to more donors will develop. Such an allocation system will likely incorporate parameters that deviate from those used for organ transplantation. To develop an effective and balanced system, the use of existing regulatory agencies that oversee solid organs should provide the maximum benefit to the patients and the society.