Aktuelle sozialpolitische und berufsgenossenschaftliche Entwicklungen

Trauma und Berufskrankheit -     

Peridural fibrosis in lumbar disc surgery--pathogenesis, clinical problems and prophylactic attempts

Postoperative peridural fibrosis is unavoidable adverse effect of lumbar disc surgery. This process is disadvantageous both to the patient and to the surgeon. It is assumed that peridural fibrosis is responsible for as much as 25% of all Failed Back Surgery Syndrome. In case of reherniated discs requiring reoperation epidural scar may cause technical difficulties. Thus the prevention or inhibition of postoperative peridural fibrosis and adhesions is an essential goal for successful lower back surgery. The authors review new opinions on pathophysiology of peridural fibrosis, clinical aspects of the process, results of experimental approaches for limiting peridural fibrosis and perspective of anti-adhesion gel Adcon-L.     

Posttraumatic ectopic calcification as an additional pathologic factor of brachial plexus palsy

The authors describe a case of a 54-year-old male, who was attacked with a broken bottle and wounded in left supraclavicular region. No neurologic deficit was observed immediately after injury. Some days later signs of upper trunk brachial plexus palsy were detected. Gradually symptoms of the Erb syndrome have developed. He was operated on 5 months after injury. During surgery no discontinuity of the brachial plexus was found. Unexpectedly there were an inner scar and free bony fragment compressing the upper trunk and the suprascapular nerve. Both the scar and bony fragment were carefully dissected and removed. Result of surgery: pain relief, restoration of normal sensation and partial restoration of biceps function.     

Disorganised Memory after Right Dorsolateral Prefrontal Damage

Neurophysiological and functional brain imaging studies suggest the importance of dorsolateral area 9/46 for modality-independent working memory. However, the behavioural manifestations following isolated damage to this area have not been clearly outlined. Here, we describe the dramatic derangement of pragmatic memory after circumscribed lesion of the right area 9/46. A 52 year-old woman had suffered a traumatic brain injury 13 years ago and sought help for what she thought was a severe memory disorder. She regularly missed appointments and had gradually lost all her friends. She had tried different strategies to compensate for her memory problem, such as writing notes on her wrist or using electronic organizers. Intelligence, attention, verbal long-term memory, and executive functions were normal. Furthermore, experimental exploration demonstrated intact time estimation, attribution of memories to ongoing reality, and anticipation of outcomes. However, she failed to rehearse and manipulate information in working memory (n-back task), confirming the findings of functional imaging studies that the mid-dorsolateral prefrontal cortex is involved in mental manipulation of information. This case exemplifies that an isolated lesion of the right area 9/46 may induce severe failure to schedule actions and memory retrieval, a disorder leading to severely disorganised behaviour and disability.     

Exploring the world with Bálint syndrome: biased bottom-up guidance of gaze by local saliency differences

Bálint syndrome is a combination of severe deficits affecting spatial attention, visuo-motor control and oculomotor function. While the severe restriction of attention (simultanagnosia) and impairments of visually guided reaching have been extensively studied, oculomotor apraxia has received comparatively little attention. The main explanatory hypothesis of oculomotor apraxia is that it is a direct consequence of the severe restriction of attention. Here, we examined in a patient with Bálint syndrome to what extent local image features such as luminance and contrast predict whether a region will be fixated or not. During the viewing of natural photographs, the patient made saccades of very small amplitude, but showed strongly increased fixation duration. In addition, the horizontal and vertical range of fixations was severely restrained compared to control subjects. When analysing the local feature content at fixation, we found that central fixations of the patient contained less local luminance and contrast than fixations of controls while he made fixations to peripheral image regions with disproportionately high luminance and contrast. These findings suggest that while our patient gazes at central regions irrespective of their local feature content, he only looks to the periphery when his gaze is captured by particularly conspicuous features. We propose that oculomotor apraxia in Bálint syndrome reflects a combination of biased representations within a parietal priority map and increased fixational activity due to biased interactions within the oculomotor network.     

AM bundle controls the anterior–posterior and rotational stability to a greater extent than the PL bundle — A cadaver study

BackgroundThe purpose of this study was to evaluate the influence of both bundles of the anterior cruciate ligament (ACL) on knee stability, anterior–posterior translation (APT) and internal (IR) and external (ER) rotation in cadaveric knees using a computer navigation system.MethodsThe APT, IR, and ER of the knees were recorded in the intact condition, the anterolateral bundle (AM) or the posterolateral bundle (PL) deficit condition and in the ACL-deficient condition. The KT-1000 arthrometer was used for APT evaluation. The measurement of rotational movements was done using a rollimeter. All tests were performed at 30°, 60° and 90° of flexion.ResultsAt 30° of flexion: In the intact knee APT was 5.8 mm, IR 12.1°, ER 10.1°. After the AM was cut, the APT increased to 9.1 mm, IR to 13.9° and ER to 12.6°. After the PL was cut, the APT was 6.4 mm, IR 13.1° and ER 10.6°. After the AM and PL were cut, the APT was 10.8 mm, IR 15.7° and the ER was 12.9° on average.ConclusionsThe AM has a greater impact on the APT than the PL in all knee joint flexion angles. The PL does not resist the rotational stability more than the AM. The rotational stability is better controlled by both bundles of ACL as compared to one bundle of the ACL.Clinical RelevanceThis study acknowledges the fact that the both bundles of the ACL are importants for AP and rotational stability of the knee joint.