[Clinical and pathological characteristics of intravascular lymphomas]. / Klinische und pathologische Charakteristika intravaskulärer Lymphome.

Intravascular B­cell lymphomas (IVL) are rare neoplasms that can manifest at any age (mean age ~62-63 years). About half of the cases are associated with Epstein-Barr virus. The most common sites of manifestation are the brain, skin, and bone marrow. The diagnosis is difficult due to unspecific clinical presentation and laboratory changes. FACS (fluorescence-activated cell sorting) and clonality analysis from peripheral blood and radiological findings are often not diagnostic. The most sensitive and most specific diagnostic method is the histopathological and immunohistochemical evaluation of a tissue biopsy. Because of the rarity of this disease, little is known about therapy and prognosis, whereby therapy is mainly similar to non-IVL lymphomas. The prognosis is poor; median survival after diagnosis is approximately one year.

Cerebral microglia activation in hepatitis C virus infection correlates to cognitive dysfunction.

Hepatitis C virus (HCV) infection may induce chronic fatigue and cognitive dysfunction. Virus replication was proven within the brain and HCV-positive cells were identified as microglia and astrocytes. We hypothesized that cerebral dysfunction in HCV-afflicted patients is associated with microglia activation. Microglia activation was assessed in vivo in 22 patients with chronic HCV infection compared to six healthy controls using [(11) C]-PK11195 Positron Emission Tomography (PET) combined with magnetic resonance tomography for anatomical localization. Patients were subdivided with regard to their PCR status, Fatigue Impact Scale score (FIS) and attention test sum score (ATS). A total of 12 patients (54.5%) were HCV PCR positive [of which 7 (58.3%) had an abnormal FIS and 7 (58.3%) an abnormal ATS], 10 patients (45.5%) were HCV PCR negative (5 (50%) each with an abnormal FIS or ATS). Patients without attention deficits showed a significantly higher accumulation of [(11) C]-PK11195 in the putamen (P = 0.05), caudate nucleus (P = 0.03) and thalamus (P = 0.04) compared to controls. Patients with and without fatigue did not differ significantly with regard to their specific tracer binding in positron emission tomography. Preserved cognitive function was associated with significantly increased microglia activation with predominance in the basal ganglia. This indicates a probably neuroprotective effect of microglia activation in HCV-infected patients.

Evidence for neuroinflammation and neuroprotection in HCV infection-associated encephalopathy.

OBJECTIVE: Fatigue, mood disturbances and cognitive dysfunction are frequent in patients infected with hepatitis C virus (HCV) who have mild liver disease. The reason is still unclear. The present study aims to gain more insight into the pathomechanism by combining an extensive neuropsychological examination with magnetic resonance spectroscopy in four different brain regions in a patient group covering the whole spectrum of neuropsychiatric findings in patients afflicted with HCV who have only mild liver disease. METHODS: 53 HCV-positive patients with only mild liver disease and differing degrees of neuropsychiatric symptoms were studied with single-voxel MRS of the parietal white matter, occipital grey matter, basal ganglia and pons. Brain metabolite concentrations were quantitatively analysed by using LCmodel. MRS data were compared to those of 23 healthy controls adjusted for age, and analysed for relationships with the extent of neuropsychiatric symptoms. RESULTS: Choline (p=0.02), creatine (p=0.047) and N-acetyl-aspartate plus N-acetyl-aspartyl-glutamate (NN, p=0.02) concentrations in the basal ganglia and choline concentrations in the white matter (p=0.045) were significantly higher in the patients than in controls. Interestingly, the difference was most evident for the patients with low fatigue scores (eg, white matter: choline: p=0.001, creatine: p=0.003, NN: p=0.031). Myo-inositol differed significantly between groups in the white (p=0.001) and grey matter (p=0.003). Fatigue correlated negatively with white matter NN, choline and creatine and myo-inositol levels in white and grey matter and basal ganglia (p<0.01). CONCLUSION: As the increase of choline, creatine and myo-inositol are usually interpreted to indicate glial activation and macrophage infiltration in chronic inflammation and slow virus infections of the brain the present data endorse the hypothesis, that HCV infection may induce neuroinflammation and brain dysfunction. The concomitant increase of NN and the negative correlation to the extent of fatigue suggest a cerebral compensatory process after HCV infection.

[The German version of parents' postoperative pain measure (PPPM-D). Validation on children 2-12 years old]. / Die deutsche Version des Parents' Postoperative Pain Measure (PPPM-D). Validierung an Kindern im Alter von 2 bis 12 Jahren.

BACKGROUND: Parents become increasingly more responsible for the postoperative pain management of their children. Useful and valid pain assessments for parents may improve pain measurement. The aim of this study was to evaluate a German version of the parents' postoperative pain measure (PPPM-D). METHODS: After translation of the PPPM into German 52 children between 2 and 12 years of age, undergoing orthopedic and trauma surgery, were included in a prospective study. At least one of the parents completed the PPPM-D on the preoperative day and the day of surgery until postoperative day 5. Both, the children's and infants postoperative pain scale (CHIPPS) for children between 2 and 4 years and the faces pain scale revised (FPS-R) for children between 5 and 12 years were also assessed. Moreover, the acceptance of the PPPM-D by the parents was assessed. RESULTS: The PPPM-D showed satisfactory reliability (Cronbach's α values = 0.77-0.87). Construct validity was demonstrated with strong correlations with the CHIPPS and the FPS-R. Discriminative validity was shown by both statistically and clinically significant differences between minor, medial and major surgeries on the first 3 days after surgery. The examination of sensitivity to change yielded promising results. The PPPM-D was well accepted by the participating parents. CONCLUSIONS: The results of this study provide evidence of the reliability, validity and high acceptance of the PPPM-D as an assessment tool of postoperative pain among children aged 2 through to 12 years of age after orthopedic or trauma surgery.

Midterm results following revision surgery in clubfeet.

Relapse rates of surgically treated clubfeet are about 25%. We reviewed 43 patients (57 feet) treated for relapsed clubfoot deformity between 1992 and 2001 in our department. The average age of the patients at the time of revision surgery was 5.1 years, the mean follow-up was 6.6 years. Surgical therapy was performed using an algorithm according to age groups. The mean Atar score at follow-up was 77 points, representing a good outcome. Out of 57 feet, 20 (35%) were rated excellent, 24 (42%) good, 5 (9%) fair, and 8 (14%) poor. The number of previous surgical interventions had no influence on the outcome. Using an age related surgical algorithm, good postoperative results could be achieved in most of our patients, thus improving their functional situation. This emphasises the usefulness of the proposed algorithm in the difficult situation of recurrent clubfoot, while thorough analysis of the underlying deformity remains essential.

Extensor hallucis longus-transfer for tibialis anterior tendon rupture repair.

OBJECTIVE: Restore the function of the tibialis anterior muscle, which is responsible for dorsiflexion and inversion of the foot. INDICATIONS: Spontaneous or traumatic rupture of the tibialis anterior tendon. CONTRAINDICATIONS: Patients with multimorbidity or lack of functional demands. SURGICAL TECHNIQUE: Direct repair of the tibialis anterior tendon with fiber-wire suture and augmentation with extensor hallucis longus tendon, potentially in combination with reinsertion of the tibialis anterior tendon in the medial cuneiform. POSTOPERATIVE MANAGEMENT: Six weeks of non-weight-bearing: 3 weeks of cast immobilization with ankle in 10° dorsiflexion, followed by 3 weeks of splint immobilization and passive mobilization. Then stepwise increase in weight-bearing over a period of 2-3 weeks. RESULTS: In 8 patients postoperative results with a mean follow-up of 13.5 months were available. One patient showed a rerupture of the augmented tendon. The mean American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score was 81.0 (range 67-88). The median ankle dorsiflexion muscle strength was 67% (range 29.3-85.5%) compared to the nonoperated leg. All patients, except the one that experienced rerupture, were very satisfied or satisfied with the result.

Plastic waste interferes with chemical communication in aquatic ecosystems.

Environmental pollution with plastic waste has gained increasing attention, as the contamination of aquatic habitats poses a challenge to these ecosystems. Plastic waste has direct negative effects on animals such as reduced growth rate, fecundity or life span. However, the indirect effects of plastic waste, which has the ability to sorb chemicals from the surrounding media, on chemical communication have yet to be investigated. Chemical communication is crucial for aquatic organisms, e.g., to avoid predation. The planktonic water flea Daphnia (Crustacea), an important link between trophic levels, relies on info-chemicals (kairomones) to assess its current predation risk and to form inducible defences. We show that plastic waste, composed of high-density polyethylene (HDPE) and polyethylene terephthalate (PET) interferes with the formation of inducible defences in Daphnia longicephala when exposed to a combination of kairomones of Notonecta glauca and plastic waste. D. longicephala shows a reduction in all defensive traits, including body length, crest width and time until primiparity, compared to exposure to solely kairomone conditioned media. Plastic waste in the absence of kairomones had no effect on defensive traits. Since it is vital to adjust these defences to the current predation risk, any misperception can have far-reaching ecological consequences. Therefore, plastic waste can have indirect effects on organisms, which may manifest at the community level.

Surgical treatment of congenital pseudarthrosis of the clavicle: a report of three cases and review of the literature.

Congenital pseudarthrosis of the clavicle is a rare entity of unknown aetiology with predominance of the right side. Our therapeutic concept is discussed with special reference to surgical therapy, histopathological findings and the most recent literature. Two girls and one boy, aged 4, 6, and 8 years, presenting with congenital pseudarthrosis of the clavicle were surgically treated between 1994 and 2000. A resection of the pseudarthrosis and internal fixation with a small reconstruction plate was performed. A bone graft from the iliac crest was used for restoration of clavicular length. Histological examination revealed a false joint with the ends of the clavicle covered by hyaline cartilage. The patients showed radiographic healing after 12 weeks. At follow-up (mean 44 months), all patients showed excellent clinical and radiological results without functional impairment. The clinical features and histological examination of the resected pseudarthroses clearly proved the diagnosis of a true congenital pseudarthrosis of the clavicle. According to our clinical and radiological results and considering the recent literature, we recommend surgical therapy with resection, bone grafting, and osteosynthesis with a reconstruction plate around the age of 4 - 6 years.

[Not Available]. / Einsatz der CT-Angiographie zur Feststellung des zerebralen Zirkulationsstillstandes.

CT-angiography (CTA) has been accredited as an additional technical method for the detection of the cessation of cerebral blood circulation in the updated German guidelines for the determination of irreversible loss of brain function. A standardized CTA protocol was defined. The evaluation of the CTA has to be done by radiologists with several years of experience in neuroradiology, preferably by radiologists certified as neuroradiologists. The so-called "stasis filling", a slow progressive spread of contrast media into the cerebral arteries despite cessation of cerebral blood circulation, has to be considered.

Pharmacological MRI (phMRI) of the Human Central Nervous System.

Pharmacological magnetic resonance imaging (phMRI) of the central nervous system (CNS) addresses the increasing demands in the biopharma industry for new methods that can accurately predict, as early as possible, whether novel CNS agents will be effective and safe. Imaging of physiological and molecular-level function can provide a more direct measure of a drug mechanism of action, enabling more predictive measures of drug activity. The availability of phMRI of the nervous system within the professional infrastructure of the Clinical Research Center (CRC) Hannover as proof of concept center ensures that advances in basic science progress swiftly into benefits for patients. Advanced standardized MRI techniques including quantitative MRI, kurtosis determination, functional MRI, and spectroscopic imaging of the entire brain are necessary for phMRI. As a result, MR scanners will evolve into high-precision measuring instruments for assessment of desirable and undesirable effects of drugs as the basic precondition for individually tailored therapy. The CRC's Imaging Unit with high-end large-scale equipment will allow the following unique opportunities: for example, identification of MR-based biomarkers to assess the effect of drugs (surrogate parameters), establishment of normal levels and reference ranges for MRI-based biomarkers, evaluation of the most relevant MRI sequences for drug monitoring in outpatient care. Another very important prerequisite for phMRI is the MHH Core Facility as the scientific and operational study unit of the CRC partner Hannover Medical School. This unit is responsible for the study coordination, conduction, complete study logistics, administration, and application of the quality assurance system based on required industry standards.

Propranolol stereoisomer plasma concentrations and portal haemodynamic response in patients with liver cirrhosis.

BACKGROUND: The haemodynamic effect of propranolol on portal pressure in patients with portal hypertension is highly variable and does not correlate with propranolol racemate plasma concentrations. AIM: To investigate the stereoselective metabolism of the propranolol enantiomers and its impact on portal haemodynamics in patients with liver cirrhosis since only S-propranolol is haemodynamically active. METHODS: Twenty patients with liver cirrhosis and portal hypertension received 40 mg propranolol orally. Portal blood velocity (PBV) and propranolol stereoisomer plasma concentrations were determined. RESULTS: During the 4 h examination period we observed a significant reduction in PBV (18.3 +/- 2.2%, P < 0.0001) vs. baseline. The area under the curve (AUC) during the study period was significantly different for the two isomers (S-propranolol 1217.0 +/- 118.5 nmol.h/L; R-propranolol 728.8 +/- 103.8 nmol.h/L, P < 0.0001). Seven patients (35%) were portal haemodynamic non-responders to propranolol. Propranolol stereoisomer AUC values were no different between responders (S-propranolol 1133. 3 +/- 132.0 nmol.h/L; R-propranolol 718.0 +/- 129.7 nmol.h/L) and non-responders (S-propranolol 1371.8 +/- 250.5 nmol.h/L; R-propranolol 746.9 +/- 200.3 nmol.h/L); neither was there a correlation between propranolol enantiomer plasma concentrations and the portal haemodynamic effect. CONCLUSIONS: Our data demonstrate a stereoselective metabolism of propranolol enantiomers in liver cirrhosis. However, following oral propranolol administration, stereoisomer plasma concentrations do not predict the portal haemodynamic effect.

Cutaneous emphysema and craniocervical bone pneumatization.

We report a case of pneumatization of the upper cervical spine and the craniocervical junction, including the occipital bone, accompanied by extensive soft tissue emphysema. There was no history of trauma or surgery. Follow-up X-ray and CT demonstrated the development of those changes. A combination of a developmental abnormality and the unusual habit of frequent Valsalva's maneuvers may have led to those findings. Clinical consequences will be discussed.

Vertebral remodeling in eosinophilic granuloma of the spine. A long-term follow-up.

STUDY DESIGN: In this study, 14 conservatively treated patients were reviewed who had eosinophilic granuloma of the spine, which had been diagnosed on the basis of histologic study of the vertebral lesion or of specimens from other sites in patients with multiple involvement. The remodeling of the vertebral body was studied in an average follow-up of 5.6 years. OBJECTIVES: To analyze the remodeling process of the involved growing vertebral body in Langerhans Cell Histiocytosis after conservative treatment and to assess the sagittal and frontal profile of the spine at the end of growth. Fourteen patients, aged between 1.2 and 11.3 years, with spinal involvement of a Langerhans' cell histiocytosis were treated in the department of orthopedics between 1980 and 1990. All patients had immobilization of the affected region by a custom-made brace. Six patients with symptomatic lesions had radiotherapy and four patients with disseminated disease were treated with chemotherapy. Clinical and radiologic examinations were made at regular intervals to evaluate the development of the vertebrae during the remodeling process. SUMMARY OF BACKGROUND DATA: In the 14 patients, both sexes were affected equally. The disease was located in the cervical spine in two patients and in thoracic and lumbar vertebrae in seven patients each. Two patients had two vertebral lesions. METHODS: The radiologic evolution of the 16 vertebral lesions was evaluated using follow-up standardized lateral radiographs. The reconstitution of the vertebral height in the presence of vertebra plana was calculated by measuring the ventral distance between the superior and inferior margins of the vertebral body in relation to the adjacent uninvolved vertebra. RESULTS: The measurements showed a growth rate of 1.5-6 (average, 3) in vertebrae with vertebra plana and a growth rate of 1.1-2.7 (average, 1.4) in the unaffected vertebra. The reconstitution of the vertebral height was between 18.2% and 63.8% of the adjacent vertebrae before and between 72.2% and 97% after skeletal maturity. CONCLUSIONS: The results demonstrate that conservative orthopedic treatment with immobilization in a brace is sufficient to allow for optimal vertebral remodeling. Partial to nearly complete reconstitution of vertebral height was seen in all cases. Thus, operative treatment with curettage of the lesion and bone grafting including multisegmental fusion with instrumentation is not necessary. In instances with neurologic impairment, rarely seen in adults, surgical decompression and short fusion of the spine is necessary. Nevertheless, complete staging and biopsy are mandatory for an accurate diagnosis.

[Software-assisted CT-postprocessing of the carotid arteries]. / Softwareassistierte CT-Nachverarbeitung am Beispiel der Karotiden.

PURPOSE: A software assistant for automatic evaluation of CT-angiograms (CTA) was developed. It should enable the visualization of the vessel lumen and the quantitative evaluation of a stenosis. CTA examinations of patients with suspected carotid artery stenoses were used for the evaluation of the software assistant. MATERIALS AND METHODS: Twelve Patients with suspected high-grade stenosis of the carotid arteries underwent a CTA examination using a multislice CT scanner. The data were analyzed and evaluated using the new software assistant. The results were compared with the data of digital subtraction angiography (DSA) of these patients. RESULTS: The time of digital postprocessing with the new software-assistant took about six minutes on average. Contour extraction of the vessel, MIP and curved MPR (c-MPR) and orthogonal cross-sectional images of the vessels were calculated, followed by an automatic quantification of stenosis by the use of the c-MPR. A good correlation was found between CTA and DSA data regarding the stenosis grade (r = 0.82). Furthermore, some information could be provided about the plaque morphology. CONCLUSION: The software-assisted detection and analysis of carotid artery stenosis with the new developed program is possible within a justifiable time. DSA- and CTA-data did not show a significant difference in stenosis grading. Further development of software tools could lead to a better characterization of plaque morphology.

[Percutaneous radiofrequency ablation of liver tumors using the LeVeen 4 cm array probe]. / Radiofrequenzablation von Lebertumoren mittels 4 cm Schirmelektrode.

BACKGROUND: The purpose of this study was to evaluate safety and efficacy of a radiofrequency ablation system in clinical practice. METHODS: In 35 patients (age 63,9 +/- 12,6 years, range 22 - 83) a total of 65 liver tumors were percutaneously treated using a 200 watt radiofrequency generator and a LeVeen 4 cm array probe (RF3000, Boston Scientific). The interventions were performed under CT guidance in local anaesthesia and sedation. Adapted to the tumor size, the LeVeen Probe was repositioned during the procedure with an additional safety margin of 1 cm. Primary tumors were colorectal in 22, and mamma tumors (n = 4), zystic pancreas tumors (n = 2), gastric cancer (n = 1), zystadenocarcinoma of the liver (n = 1), lung cancer (n = 1), gastrointestinal stroma tumor (n = 1), duodenal carcinoma (n = 1), cholangiocellular carcinoma (n = 1) and hepatocellular carcinoma (n = 1). Post interventional control and follow-up was performed with multislice-CT (collimation 2.5 mm, unenhanced and contrast enhanced, arterial and portal filling) at 4 weeks, and every three months. RESULTS: One to 4 metastases were treated per patient during one or up to 4 procedure sessions. Mean lesion size was 2,3 +/- 1,2 cm (range 0,2 to 7,0). The corresponding size of the necrosis achieved was 4,6 +/- 1,4 cm (range 2,0 - 8,2). Primary technical success with complete tumor ablation was reached in 60 of 65 lesions. In 4 cases two treatment sessions were necessary in order to achieve the intended results. In one case the procedure was aborted because of a close relationship between lesion and right colon. 63 tumors were treated in sedation and local anesthesia. General anesthesia was necessary in two cases, in one who refused intervention in sedation, and in another case with insufficient analgetic effect. Morbidity was 9.2 %: Bleeding complications (n = 3, one arterial bleeding from the ablation tract, two intrahepatic bleedings with extrahepatic hematoma) were confirmed by selective angiography of the hepatic artery and were treated with coil embolisation of the respective segmental arteries. One case with subcapsular tumor ablation suffered from a large subcapsular hematoma requiring a blood transfusion. In one case with a subphrenic location of the metastasis, the needle electrode had passed the costophrenic recessus and resulted in an hematothorax. This patient was treated by pleural drainage for two days. One patient suffered from fever up to 39 degrees C and inflammation of the biliary tract and received a cholecystectomy 22 days post interventionally. There was no peri interventional mortality. Mean follow-up is 5,6 +/- 3,3 months (range 0 to 13). 21 of 35 patients showed no evidence of tumor recurrence. One case is scheduled for a second treatment session for complete tumor ablation. 13 of 35 patients suffered from tumor recurrence, either local recurrences and/or new metastases. At the sites of prior RF-ablation 9 local recurrences were detected in 7 patients, two cases with isolated local recurrences and 5 cases with local recurrences and new metastases. 6 Patients showed no evidence for local recurrences but new metastases. In these 11 cases a total of 37 metastases were found at new locations. In three patients tumor recurrence was treated by means of a second RF-ablation. The remaining 10 patients received chemotherapy. CONCLUSION: RF-ablation can be performed in local anaesthesia and sedation with low peri interventional morbidity and mortality. Using the LeVeen probe and a 200 watt generator, appropriate necroses can be achieved. CT follow-up is required every three months because of the tumor recurrence rate and reinterventions may be required.

[TIPSS: technical and clinical results after 4 years]. / TIPSS: Technische und klinische Ergebnisse nach 4 Jahren.

PURPOSE: Retrospective analysis of the technical and clinical results after transjugular portosystemic stent shunt (TIPSS) procedure. METHOD: Between 1992 and 1996 we tried to establish a TIPSS in 90 patients. The indications were: recurrent variceal haemorrhage (n = 74), refractory ascites (n = 12), hepatorenal syndrome (HRS) (n = 4). Due to advanced liver cirrhosis 16 patients suffered of severe renal dysfunction (HRS). 57 patients had ascites. RESULTS: TIPSS implantation was technically successful in 96.7% (1992-1994: 5.1%, 1995-1996: 100%) of the patients. Complications occurred in 14.9% (1992-1994: 25.6%, 1995-1996: 6.3%). TIPSS-associated mortality was 2.3% (1992-1994: 5.1%, 1995-1996: 0%). 76.1% of the patients required reinterventions. 85.3% of reinterventions were necessary in the first year after TIPSS placement. The survival rate without reintervention was 28%, 21% and 9% for Child A, B, and C patients, respectively. Recurrent variceal haemorrhage occurred in 12.7%. De novo hepatic encephalopathy developed in 13.8%. Ascites improved in 79.2% and renal function in 75% of the patients. CONCLUSION: TIPSS is an effective method to treat recurrent variceal haemorrhage, refractory ascites and HRS. Complication and mortality rate depend on the investigator's experience and on the technique used.

Risk-benefit analysis of prophylactic pinning in slipped capital femoral epiphysis.

There is a broad and controversial discussion about the surgical procedure and the type of hardware for internal transfixation of the epiphysis and metaphysis in slipped capital femoral epiphysis (SCFE). Prophylactic pinning is even more controversial. One hundred and nine patients showing SCFE underwent a one-stage bilateral fixation of the epiphysis with three or four Kirschner wires (pins). From these 109 patients (69 male and 40 female), 94 had an unilateral slip and were operated prophylactically on the contralateral side. There were no complications such as avascular necrosis of the femoral head, chondrolysis, bone fracture, failure of metal implant, osteomyelitis or deep wound infection either at the time of surgery or at the minimum follow-up of 1 year with prophylactic pinning in SCFE. Therefore, we consider pinning allows for efficient stabilization, reliably preventing any progression of SCFE on the affected side and, furthermore, prevents the incidence of a secondary slip on the primarily nondisplaced contralateral side. The transfixation of epiphysis and metaphysis with Kirschner wires (pins) shows good subjective and objective long-term results compared with other surgical methods and implants. There is only a low morbidity rate with this method, because reoperations may only become necessary in the younger age group owing to normal growth of the femoral neck, compared with a high benefit from prophylactic surgical treatment of the nonaffected opposite side at the time of unilateral onset of the disease. The pins may no longer catch the epiphysis but further growth will allow for remodeling of the femoral head and for an optimal neck/shaft ratio. In case of further growth and relative shortening of the pins, refixation may become necessary. Therefore, we like to recommend the Kirschner-wire transfixation (pinning) of the epiphysis and metaphysis in patients with SCFE for primary treatment of SCFE as well as for prophylactic pinning of the contralateral side in one sitting.

Recurrent clubfoot.

About 25 % of operated clubfeet will develop a recurrency or show a marked residual deformity. As main factor the failure of concentric reduction at the time of initial surgery has to be considered. Residual forefoot adduction and supination are the most common persistent deformities. Based on the experience with 94 recurrent/residual clubfeet (patients < 10 years) the surgical treatment at different age-groups is presented. As a general rule soft tissue release is applicable as a repeated procedure until the age of about eight to ten years. For revision in patients between two and eight years we recommend a closing wedge osteotomy of the cuboid and a tibialis transfer additional to repeated release-procedures. In patients older than eight to ten years mid-tarsal osteotomies, correction according to Ilizarov with the external fixator or triple arthrodesis are to be considered as single or combined procedures.

Biomechanical analysis of Graf's dynamic spine stabilisation system ex vivo.

The most frequent causes of chronic lumbar spine instability are of degenerative or traumatic origin. Numerous anterior and posterior stabilisation devices were developed for anatomical reconstruction of the spinal alignment and fusion of the spine to restore stability. Fusion of the spine results in increased load of adjacent segments with an increased risk of secondary degeneration which might result in instability or stenosis. To avoid the disadvantages of static devices, Graf developed a method of dynamic surgical treatment of spinal column instabilities, which is based on the principle of flexible stabilisation. This study is analysing the kinematics of discoligamentary intact motion segments compared with the experimentally destabilised human lumbar spine and the influence of Graf's stabilisation. According to our results, rotational instabilities cannot be satisfactorily stabilised by Graf's ligamentoplasty. With the present ex vivo study, it could be shown that it is possible to restore stability after discoligamentary lesion and after facetectomy using Graf's dynamic lordosis ligamentoplasty.