Björn Dirk Krapohl

Angiogenic Effects of Injected VEGF165 and sVEGFR-1 (sFLT-1) in a Rat Flap Model

BACKGROUND Injections of single-dose vascular endothelial growth factor (VEGF)(165) have been advocated as a therapeutic tool for angiogenesis in ischemic flaps. We challenged this thesis by employing both VEGF(165) and vascular endothelial growth factor receptor-1 (VEGFR-1) (for competitive inhibition of VEGF signal transduction) in different experimental settings of an ischemic rat flap model. MATERIAL AND METHODS 80 isogenic rats were divided in two groups of 40 animals (groups 1A-1D and 2A-2D). The ischemic target was a 7 x 7-cm epigastric island flap, based on the right inferior epigastric pedicle. Group 1 received flap treatment 1 week prior to flap elevation by test substance injection into its flap panniculus carnosus: 1 ml NaCl 0.9% (1A), 1 ml Dulbeccos modified Eagles medium (1B), 1.0 microg VEGF(165) (1C), and 10 microg sFLT-1 with 1.0 microg VEGF(165) (1D). sFLT-1 is a soluble receptor for VEGF and is able to prevent VEGF signaling through the cell surface receptor. Group 2 had the same flap treatment at the day of flap elevation. RESULTS In group 1C we found the most vital flap tissue, without reaching significance. Compared with group 1D, however, significantly more flap tissue maintained vital. In groups 2A-2D, no significant results were found with respect to flap survival. CONCLUSIONS Local application of single-dose VEGF(165) 1 week prior to ischemia dose not have significant clinical angiogenic effects. In this experimental setting, VEGF(165)-induced angiogenic effects can be significantly inhibited by adding sFLT1 in vivo. A single-dose of VEGF(165) under ischemic conditions causes no significantly better flap survival in this model.

A rare vasoproliferative lesion: angiolymphoid hyperplasia with eosinophilia of the hand

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare vasoproliferative lesion of uncertain aetiology, involving the skin and subcutaneous tissue. The predilection of the tumour-like lesion is for the head and neck region. Radical surgical excision is still regarded as the most effective treatment. We present the case of a 33-year-old female with ALHE of the right hand. Preoperative MRI and angiography demonstrated involvement of the fourth and fifth rays, with complete occlusion of the ulnar artery, and a small lesion at the level of the metacarpophalangeal joint of the index finger. Complete tumour excision could not be achieved without resection of the fourth and fifth rays. One year postoperatively, there were no clinical signs of recurrence. The patient refused any further invasive diagnostic and follow-up examinations. Angiolymphoid hyperplasia of the hand is a rare disease, and patients should undergo early surgical treatment to achieve complete excision of the lesion.

Effect of tissue-plasminogen activator on leukocyte-endothelial interactions at the microcirculatory level.

&NA; In free tissue transfer and replantation surgery, there is a debate over whether any pharmacologic agents should be used to improve vessel patency and tissue survival. Because tissue‐plasminogen activator (t‐PA) is a highly effective and safe fibrinolytic, it may be useful in obtaining and maintaining vessel patency. The direct effects of t‐PA on skeletal muscle hemodynamics and leukocyte activation at the microcirculatory level were investigated. Male Sprague‐Dawley rats (n = 20) were divided into three experimental groups: control (n = 8), vehicle (n = 6), and t‐PA (n = 6). Using the cremaster muscle flap model and intravital microscopy, red blood cell velocity, vessel diameter, capillary perfusion, endothelial edema index, and leukocyte‐endothelial interactions (rolling, adhering, and transmigrating leukocytes) in postcapillary venules were measured. In the vehicle and t‐PA groups, vehicle or t‐PA was infused by means of a catheter inserted into the lower abdominal aorta for local infusion. Except for a significant reduction in the diameter of the first order arterioles from 117 &mgr;m to 82 &mgr;m (medians; p = 0.026), t‐PA did not significantly affect red blood cell velocity, vessel diameter, or capillary perfusion compared with vehicle. However, leukocyte‐endothelial interactions did differ significantly in postcapillary venules. Adhering leukocytes counted per visual field decreased from 4.67 in the vehicle group and 3.50 in the control group to 1.67 in the t‐PA group (medians; p = 0.015 and p = 0.005, respectively); transmigrating leukocytes in the t‐PA group decreased from 4.75 in the vehicle group and 3.50 in the control group to 1.67 in the t‐PA group (medians; p = 0.002 and p = 0.043, respectively). t‐PA treatment significantly decreased the number of both adhering and transmigrating leukocytes. These novel findings on leukocyte‐endothelial interactions suggest that t‐PA has anti‐inflammatory effect. (Plast. Reconstr. Surg. 102: 2388, 1998.)

Current concepts review: Fractures of the patella

Fractures of the patella account for about 1% of all skeletal injuries and can lead to profound impairment due to its crucial function in the extensor mechanism of the knee. Diagnosis is based on the injury mechanism, physical examination and radiological findings. While the clinical diagnosis is often distinct, there are numerous treatment options available. The type of treatment as well as the optimum timing of surgical intervention depends on the underlying fracture type, the associated soft tissue damage, patient factors (i.e. age, bone quality, activity level and compliance) and the stability of the extensor mechanism. Regardless of the treatment method an early rehabilitation is recommended in order to avoid contractures of the knee joint capsule and cartilage degeneration. For non-displaced and dislocated non-comminuted transverse patellar fractures (2-part) modified anterior tension band wiring is the treatment of choice and can be combined – due to its biomechanical superiority – with cannulated screw fixation. In severe comminuted fractures, open reduction and fixation with small fragment screws or new angular stable plates for anatomic restoration of the retropatellar surface and extension mechanism results in best outcome. Additional circular cerclage wiring using either typical metal cerclage wires or resorbable PDS/non-resorbable FiberWires increases fixation stability and decreases risk for re-dislocation. Distal avulsion fractures should be fixed with small fragment screws and should be protected by a transtibial McLaughlin cerclage. Partial or complete patellectomy should be regarded only as a very rare salvage operation due to its severe functional impairment.

Results after simple decompression of the ulnar nerve in cubital tunnel syndrome

Cubital tunnel syndrome represents the second most common compression neuropathy of the upper limb. For more than four decades there has been a controversy about the best surgical treatment modality for cubital tunnel syndrome. In this study the results of 28 patients with simple ulnar nerve decompression are presented. Data analyses refers to clinical examination, personal interview, DASH-questionnaire, and electrophysiological measurements, which were assessed pre- and postoperatively. 28 patients (15 females, 13 males) were included in this study. The average age at time of surgery was 47.78 years (31.68–73.10 years). The period from onset of symptoms to surgery ranged from 2 to 24 months (mean 6 months). The mean follow-up was 2.11 years (0.91–4.16 years). Postoperatively there was a significant decrease in DASH score from 52.6 points to 13.3 points (p<0.001). Also the electrophysiological findings improved significantly: motor nerve conduction velocity increased from 36.0 m/s to 44.4 m/s (p=0.008) and the motor nerve action potential reached 5,470 mV compared to 3,665 mV preoperatively (p=0.018). A significant increase of grip strength from 59% (in comparison to the healthy hand) to 80% was observed (p=0.002). Pain was indicated by means of a visual analog scale from 0 to 100. Preoperatively the median level of pain was 29 and postoperatively it was 0 (p=0.001). The decrease of the two-point-discrimination of the three ulnar finger nerves was also highly significant (p<0.001) from 11.3 mm to 5.0 mm. Significant postoperative improvement was also observed in the clinical examination concerning muscle atrophy (p=0.002), clawing (p=0.008), paresthesia (p=0.004), the sign of Froment (p=0.004), the sign of Hoffmann-Tinel (p=0.021), and clumsiness (p=0.002). Overall nearly 90% of all patients were satisfied with the result of the operation. In 96.4% of all cases, surgery improved the symptoms and in one patient (3.6%) the success was noted as “poor” because the symptoms remained unchanged. In 35.7% the success was graded as “moderate”, in 10.7% as “good” and in 50.0% as “very good”.

Ein neues gentechnologisches Modell zur Angiogeneseinduktion mittels ex vivo transfizierter isogener Fibroblasten

Introduction We have developed a new model for temporary production of angiogenic proteins by using adenovirally transfected isogenic fibroblasts as carriers.

Retrospective analysis of a VACM (vacuum-assisted closure and mesh-mediated fascial traction) treatment manual for temporary abdominal wall closure – results of 58 consecutive patients

Introduction: The optimal treatment concept for temporary abdominal closure (TAC) in critically ill visceral surgery patients with open abdomen (OA) continues to be unclear. The VACM (vacuum-assisted closure and mesh-mediated fascial traction) therapy seems to permit higher delayed primary fascial closure rates (FCR) than other TAC procedures. Material and methods: Patients of our clinic (n=58) who were treated by application of a VAC/VACM treatment manual in the period from 2005 to 2008 were retrospectively analysed. Results: The overall FCR of all patients was 48.3% (95% confidence interval: 34.95–61.78). An FCR of 61.3% was achieved in patients who had a vicryl mesh implanted at the fascial level (VACM therapy) in the course of treatment. Mortality among patients treated with VACM therapy was 45.2% (95% CI: 27.32–63.97). Conclusions: The results of our own study confirm the results of previous studies which showed an acceptable FCR among non-trauma patients who were treated with VACM therapy. VACM therapy currently appears to be the treatment regime of choice for patients with OA requiring TAC.

All-arthroscopic treatment of tibial avulsion fractures of the posterior cruciate ligament

Background: The posterior cruciate ligament (PCL) avulsion fracture from its tibial insertion is a rare condition. Despite the further technical advent in refixation of avulsion fractures, the reported failure rate of current approaches remains high and the optimal surgical technique has not been elucidated yet. The purpose of the current study is to present an all-inside arthroscopic reconstruction technique for bony tibial avulsion fractures of the PCL and initial clinical outcomes. Methods: Patients underwent a thorough clinical and radiological examination of both knees at 3, 6, 12, 18, and if possible also at 24 months. Clinical evaluation included subjective and objective IKDC 2000, Lysholm score, and KOOS score. Radiographic imaging studies included CT scans for assessment of osseous integration and anatomic reduction of the bony avulsion. In addition to that posterior stress radiographs of both knees using the Telos device (Arthrex, Naples, USA) were conducted to measure posterior tibial translation. Results: A total of four patients (1 female, 3 male; ø 38 (± 18) years), who underwent arthroscopic refixation of a PCL avulsion fracture using the Tight Rope device were enrolled in this study. Mean follow up was 22 [18–24] months. The mean subjective IKDC was 72.6% (± 9.9%). Regarding the objective IKDC three patients accounted for grade A, one patient for grade C. The Lysholm score yielded 82 (± 6.9) points. The KOOS score reached 75% (± 13%; symptoms 76%, pain 81%, function 76%, sports 66%, QoL 64%). All patients showed complete osseous integration and anatomic reduction of the bony avulsion. The mean posterior tibial translation at final follow up was 2.8 [0–7] mm. Conclusions: All-arthroscopic treatment of tibial avulsion fractures of the posterior cruciate ligament provides satisfactory clinical results in a preliminary patient cohort. It is a reproducible technique, which minimizes soft tissue damage and obviates a second surgery for hardware removal. Further clinical studies with larger patient cohorts and a control group are needed to further confirm these preliminary results.

Current diagnostics and treatment of the cubital tunnel syndrome in Austria.

According to the vote of the Austrian Society for Surgery of the Hand (ÖGH) an investigation to collect data on the current state of the treatment of cubital tunnel syndrome was initiated. Over one year a total of 875 patients with cubital tunnel syndrome were operated in Austria, this means an incidence of this nerve entrapment of 0.011%. Most of the operations were done by trauma surgeons (287; 33%). For diagnosis most of the centers rely on clinical symptoms, electroneurophysiology, and elbow X-ray. 40% of the institutions regard conservative therapy as useless and not indicated. If conservative treatment modalities are applied, physiotherapy (97%), non-steroidal anti-inflammatory medication (77%), and glucocorticoid injections (30%) are primarily used. In case of simple nerve entrapment most of the surgeons (72%) prefer simple nerve decompression. If there is additional pathology subcutaneous cubital nerve transposition is recommended (62%). Endoscopic techniques are only use by 3% of the surgeons. In the postoperative care, physiotherapy is favored in 51%, whereas 24% do not judge any postoperative care as beneficial. The three most often encountered complications were incomplete remission, scar contracture and hypertrophy, and postoperative bleeding.

Iatrogenic nerve lesions of the upper extremity.

Thirty-three patients are presented who suffer from iatrogenic nerve injury of the upper extremity. Depending on the nature, duration, and degree of nerve injury, we performed neurolysis (16), direct nerve coaptation (4), and nerve grafting (13). Fourteen (70%) of 20 patients presenting with motor nerve injury achieved motor function against resistance. In 26 of 30 patients (87%) with sensory nerve involvement, at least some superficial sensory function was restored. Surgeons should be familiar with clinical and electroneurophysiological tests for early diagnosis of iatrogenic nerve injuries to allow early intervention for maximal nerve recovery.