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U Bosch

Publications and source records attributed to U Bosch.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Minimally invasive screw fixation of the intracapsular femoral neck fracture in elderly patients].

INTRODUCTION: Increasing life expectancy is associated with an increase of geriatric fractures such as intracapsular femoral neck fractures. Their treatment by arthroplasty imposes a significant burden on our health care system. METHODS: In an open clinical study we investigated the complication rate of a less expensive and less invasive, femoral head saving operative procedure. Between June 1997 and June 2000, 205 intracapsular femoral neck fractures of elderly patients (mean age 78.1 +/- 11.8 years) were fixed with cannulated screws. RESULTS: Seventy-seven percent were displaced fractures and 15.6% were impacted Garden I fractures. Reoperation after internal fixation occurred in 38 patients. The most frequent cause of reoperation was secondary arthroplasty due to redisplacement (14x), femoral head necrosis (10x) and non-union (7x). Implant removal (4x), wound hematoma (1x) and femoral head penetration by screws (2x) were other causes for reoperation. CONCLUSION: Less invasive cannulated screw fixation of intracapsular femoral neck fractures should be considered as a treatment option, because it is a smaller and less expensive operation than prosthetic replacement. Adequate reduction and screw placement, however, are a prerequisite for successful outcome.

Aged↗
PubMed2001

[Acute acromioclavicular joint dislocation--operative or conservative therapy?].

42 patients with complete acromioclavicular dislocation treated operatively and 38 patients managed non-operatively were examined retrospectively with a mean follow-up of 6.3 +/- 2.5 years. The dislocations in both groups included type III and type V injuries according to the Rockwood-classification. The operative technique was suturing of the tom ligaments and stabilization of the acromioclavicular joint using resorbable coracoclavicular PDS-banding. In non-operative treatment, early physiotherapy accepting the deformity was performed in most of the patients. The clinical results using the UCLA- and the Constant-Murley score as well as evaluation of pain, function and strength were similar in both groups. Those patients suffering from a more severe dislocation type Rockwood V who were treated non-operatively had as good results as those patients with grade III dislocation. Posttraumatic osteoarthritis developed mainly in those patients whose acromioclavicular joint healed in partial dislocation. Non-operative treatment was equal even in less severe dislocations in the subgroup of type Rockwood V injuries. The persisting deformity which must be expected in non-operative treatment did not affect the patient's outcome regarding pain, function and strength of the shoulder.

Acromioclavicular Joint↗
PubMed2001

[Knee joint prosthesis implantation after fractures of the head of the tibia. Intermediate term results of a cohort analysis].

A significant number of patients with operated tibial plateau fractures develop osteoarthritis and require total knee arthroplasty. In cases of primary osteoarthritis the results are generally good. However, it is not known whether patients with post-traumatic osteoarthritis obtain comparably favorable results. In a retrospective study we analyzed 72 patients who had undergone a self-aligning (SAL) total knee arthroplasty. Ten patients received arthroplasty due to sequelae of a tibial head fracture (group I). The median time to follow-up in this group was 30 months. Clinical and radiological evaluation was based on the Knee Society Clinical Rating System. The score comprises pain, range of motion, stability, and function. We defined the axis and possible loosening by radiological examination. For comparative descriptive statistics, a cohort of patients was chosen who had received an arthroplasty because of primary gonarthrosis (group II, 76 arthroplasties in 62 patients). The median time to follow-up in this group was 46.5 months. Three patients in group I underwent revision surgery, four patients displayed severe functional deficits and pain, and one patient had a varus deformity with good clinical function. This corresponded to an early complication rate of 27% and a late complication rate of 36%; a relevant instability or loosening of the components did not occur in this group. In group II the incidence of early complications was 10%. The patients in group I reached a mean value of 153 points using the rating system vs 167 points in group II. Analyzing the clinical parameters of the score, we found that patients in group I experienced significantly more pain, thereby affecting functions of daily living, such as walking and climbing stairs. Because of the small number of patients in group I, conclusions can only be drawn to a limited extent. However, we saw that these patients displayed a higher incidence of complications and performed less well. This has to be taken into consideration and discussed prior to surgery.

Activities of Daily Living↗
PubMed2001

[Outcome analysis after open reconstruction of rotator cuff ruptures. A comparative assessment of recent evaluation procedures].

Outcome evaluation is becoming increasingly important for reconstructive surgery in musculoskeletal diseases. In addition to established shoulder-scores, new outcome-scores are being developed to cover all effects caused by a disease or intervention. Three validated, self-administered shoulder questionnaires were applied prospectively in 23 otherwise healthy patients suffering from rotator cuff deficiency. These were correlated to the Constant-Murley Shoulder Score and to a visual analogue scale for satisfaction. 7 women and 16 men with combined tears of supraspinatus and infraspinatus (mean age 55.3 +/- 10.5, r/l: 14/9, FU 57.8 +/- 15.7 weeks) were gathered prospectively and evaluated pre- and postoperatively with the American Shoulder and Elbow Surgeons Shoulder Index (ASES), the Simple Shoulder Test (SST) and the Disabilities of the Arm, Shoulder and Hand Module (DASH questionnaire). In addition, a visual analogue scale for satisfaction was employed. All four scores as well as the visual analogue scale revealed improvement at a statistically significant level (paired, two-tailed t-test, P < 0.01) after surgery. All questionnaires had a significant correlation with the Constant-Murley Shoulder Score (Pearson's correlation coefficient: ASES: r = 0.871, P < 0.01; DASH: r = -0.758, P = < 0.01; SST: r = 0.494, P < 0.05). All were easy to apply and provided a reliable, postoperative evaluation of shoulder function. The SST was easy to apply, however compound outcome analysis was only possible with the ASES Shoulder Index and the DASH questionnaire. The DASH scale was the most complex evaluation instrument. The Constant-Murley Shoulder Score comprises a physical examination which is advantageous but must be carried out in the clinic. For postoperative assessment, without the patient having to return to the clinic, the ASES Shoulder Index is preferred as it correlates well with the Constant-Murley Shoulder Score (r = 0.871) and the visual analogue scale for satisfaction (r = 0.762).

Adult↗
PubMed2001

Cyclic mechanical stretching enhances secretion of Interleukin 6 in human tendon fibroblasts.

Accelerated rehabilitation after tendon and ligament injuries is widely accepted to avoid adverse effects of immobilization. However, progressive rehabilitation may also lead to an excessive inflammatory soft tissue response. To investigate the amount of loading necessary to accelerate the healing process without causing damage to the healing tissue, we experimentally stretched human tendon fibroblasts of healthy tendons 15 and 60 min with 1 Hz and an elongation of 5% and measured the secretion of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta1 (TGF-beta1), platelet-derived growth factor (PDGF), and fibroblast growth factor basic (bFGF). Secretion of IL-6 was significantly induced by 15 min of cyclic biaxial mechanical stretching after 4 and 8 h observation time and by 60 min stretching and 2 h observation time. The growth factors TGF-beta1, bFGF, and PDGF were secreted by human tendon fibroblasts both in stretched cells and controls; however, no increases were related to mechanical stretching. There was no measurable secretion of TNF-alpha in human tendon fibroblasts. These findings suggest that the inflammatory reaction often seen during physiotherapy after tendon and ligament injuries is caused in part by secretion of IL-6 from the stretched human tendon fibroblasts. IL-6 may cause exaggerated proliferation of fibroblasts and synovial cells as seen in rheumatoid arthritis and arthrofibrosis. However, physiological proliferative reactions leading to repair of injured tissue are also possible. IL-6 measured in the synovial fluid may be an important predictor for monitoring and improving therapeutic strategies in terms of tendon/ligament healing.

Cell Line↗
PubMed2001

Arthrofibrosis is the result of a T cell mediated immune response.

It is thought that an excessive fibrotic healing response with diffuse intra-articular scarring leads to arthrofibrosis after trauma and surgery around joints. To clarify the specific cellular mechanism of arthrofibrosis during arthrolysis we took fibrotic tissue samples from 18 patients at varying periods after knee trauma or surgery. Sections were stained with hematoxylin and eosin to study the overall histopathological changes. Major histocompatibility complex (MHC) class II expressing cells as well as CD3, CD4, CD25, CD28, CD68, CD80, and CD83 positive cells were localized immunohistologically. The results demonstrated synovial hyperplasia with fibrotic enlargement of the subintima and infiltration of inflammatory cells. The number of MHC class II expressing cells was increased. Mainly, intimal macrophages and dendritic cells showed positive immunostaining for MHC class II antigens. In the subintima moderate infiltration of T cells including activated T cells (CD25), CD4+ T helper (Th) cells and Th1 and Th2 subsets was detected. There was a slight polarization of the Th1/Th2 balance towards Th1 differentiation. Positive immunostaining for CD80/CD28 indicated the costimulatory signal for T cell activation and clonal expansion. These findings strongly support an immune response as the cause of capsulitis leading to formation of diffuse scar tissue within the knee joint. Based on our immunohistological study we conclude that a T cell mediated immune response plays a crucial role in the mechanism of arthrofibrosis.

Adolescent↗
PubMed2001

Cyclic mechanical stretching modulates secretion pattern of growth factors in human tendon fibroblasts.

The objective of the study was to investigate whether the response profile of the growth factor of human tendon fibroblasts could be beneficially influenced through the application of mechanical stretch. It was considered that this would elucidate structural and functional problems, often seen after tendon and ligament healing. The secretion pattern of transforming growth factor-beta (TGF-beta), platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) was determined in mechanically stretched fibroblasts and compared to non-stretched controls. Human tendon fibroblasts were experimentally stretched for 15 and 60 mm at a frequency of 1 Hz and an amplitude of 5%. The secretion of TGF-beta PDGF and bFGF was measured by enzyme-linked immuno-sorbent assay. All the growth factors investigated were indeed secreted by human tendon fibroblasts both in stretched cells and controls. Mechanical stretch increased the secretion pattern of the growth factors. The increased concentrations of TGF-beta bFGF and PDGF after cyclical mechanical stretching may have a positive influence on tendon and ligament healing through stimulation of cell proliferation, differentiation and matrix formation.

Adult↗
PubMed2001

[Bone screw osteosynthesis of medial femoral neck fracture in elderly patients].

This study evaluated the complication rate and surgical outcome following cannulated screw fixation of femoral neck fractures in elderly patients. Between 1.6.97 and 31.12.98 we operated on 110 patients with 112 fractures. The mean age was 78.4 years (range 25-96 years). Mean follow up was 6.8 months (range 3-16 months). The mortality rate was 22.7% (25/110). 60 patients with 61 fractures could be evaluated for complications, reoperations, pain and walking ability. 68.9% of the fractures healed. Avascular necrosis developed in 18%. Non-union rate was 8.2% and redislocation rate 4.9%. 18 patients needed a second operation, two thirds received an arthroplasty and one third had implant removal or replacement. In 81.6% of the patients (the patients with secondary arthroplasty excluded) pain relief was good. Insufficient reduction and malposition of the screws are the most common causes for failure of cannulated screw fixation of femoral neck fractures in the elderly.

Adult↗
PubMed2001

Proprioception in anterior cruciate ligament reconstruction. Endoscopic versus open two-tunnel technique. A prospective study.

ACL-reconstruction with patellar tendon autograft is a standard procedure which can be performed arthroscopically with a femoral half tunnel drilled from the joint or using the two-tunnel technique with medial miniarthrotomy and additional femoral approach. The arthroscopic procedure with single incision was hypothesized to improve proprioception and to provide earlier rehabilitation. Twenty-nine patients with chronic ACL-deficiency were included in the prospective study. Fifteen patients were operated endoscopically, 14 patients using the two-tunnel technique. Proprioception, Lysholm and Tegner scores as well as stability (KT-1000) were assessed preoperatively, 3 and 6 months postoperatively as well as after 3.9 +/- 0.4 years. A significant deficit of proprioception was assessed in both groups preoperatively. Six months postoperatively, both groups showed a restitution of proprioception near full extension and full flexion of the knee. In the mid-range position, the proprioception could not be restored. At the final examination after 3.9 years, the deficit documented in the mid-range position still persisted. There were no differences in proprioception, clinical results and stability between the arthroscopic and the open technique.

Adult↗
PubMed2001

[Chronic instability and fixed dislocation of the shoulder].

Chronic instabilities may be traumatic or atraumatic, unidirectional or multidirectional. It is important to distinguish between symptomatic instability and asymptomatic hyperlaxity. Posttraumatic, unidirectional anterior instability without hyperlaxity is the most common form of instability. The patient presents apprehension, the sulcus-sign is negative. Posttraumatic, unidirectional instability with hyperlaxity is due to an adequate trauma, both the apprehension test and the sulcus sign are positive. The treatment of traumatic instability is surgically with respect to the underlying pathology of the ligaments, labrum and capsule. The "golden standard" is the reconstruction of the capsulolabral complex. The repetitive microtraumatic instability is seen in overhead athletes with elongation or disruption of the capsule. The typical patient presents with painful subluxations, the instability may be unidirectional or multidirectional. The treatment is conservatively. Multidirectional instability with hyperlaxity is defined as symptomatic instability in at least two directions of instability with multidimensional hyperlaxity. These individuals will also report on pain rather than instability. The apprehension test is positive in at least two directions, the sulcus sign is positive as well. The patients are responsive to an intensive rehabilitation program for 6-12 months. Open capsular shift or thermal capsular shrinkage may be successful after failed conservative treatment. Multidirectional instability without hyperlaxity is extremely rare and is due to more than one adequate trauma with traumatic instability in different directions. The apprehension test is positive, the sulcus sign negative. The treatment is surgically. The fixed dislocation is posterior in most of the cases and frequently being missed primarily. It is seen in unconscious, multiple-injured patients or after grand mal or electroshock seizures. The reduction may be either closed or open depending on the interval between trauma and diagnosis. Voluntary instability represents a subset of individuals with atraumatic instability. The patients can dislocate and reduce their shoulder, have no pain and do not develop arthritis. They do not require a special therapy.

Adult↗
PubMed2000

[Expression of type VI collagen in arthrofibrosis. An immunohistochemical study].

Arthrofibrosis is a disabling complication after trauma and surgery due to massive connective tissue proliferation. The etiology and pathogenesis have never been fully understood. A strong immune response may lead to activation and proliferation of fibroblasts with excessive and disordered deposition of matrix proteins. In similar pathological conditions, like lung fibrosis or superficial fibromatoses with fibrotic transformation an increased expression of collagen type VI has been reported. We investigated fibrotic tissue samples taken from 18 patients (average age: 32.7 years), who underwent arthrolysis of the knee joint because of symptomatic arthrofibrosis following ligament injury. The mean interval between trauma and arthrolysis was 13.8 months (range 4-50 months). Tissue samples were taken from the infrapatellar fat pad and intercondylar connective tissue. All samples were stained with HE. The expression of type III and VI collagen was studied immunohistochemically using an immunoperoxidase method for light microscopic visualization. Histologic analysis from patients with arthrofibrosis showed a synovial hyperplasia with cell infiltration and vascular proliferation compared to synovial tissue samples from knee joints without any detectable pathology. Subsynovial an increased deposition of matrix proteins was visible. Type VI collagen was widely distributed as a network subsynovial and around capillary walls. Type III collagen showed a diffuse distribution. Arthrofibrotic tissue is, similar to pathological conditions with fibrotic transformation characterized by an increased expression of collagen type VI. Collagen type VI may play an important role in matrix homeostasis. It serves as an anchoring element between collagen fibers and as a cell binding structure.

Adolescent↗
PubMed2000

[Proprioception after reconstruction of the anterior cruciate ligament. Endoscopic vs. 2 tunnel technique].

ACL reconstruction with patellar tendon autograft is a standard procedure which can be performed arthroscopically with a femoral half tunnel drilled from the joint or using the two-tunnel technique with medial miniarthrotomy and additional femoral approach. The arthroscopic procedure with single incision was supposed to increase stability and to improve proprioception by earlier rehabilitation. 29 patients with ACL deficiency were included in the study. 15 patients were treated endoscopically, 14 patients by using the two-tunnel technique. Proprioception, Lysholm and Tegner scores as well as stability (KT-1000) were assessed preoperatively, 3 and 6 months postoperatively. A deficit of proprioception was assessed in either group preoperatively, which could be improved after 3 months only in the arthroscopic group. 6 months postoperatively, either group showed a restitution of proprioception near full extension and full flexion of the knee. In the mid range position, the proprioception could not be restored. There were no differences in stability and the Lysholm and Tegner scores between the groups after 6 months postoperatively. The comparison between the patients with acute and chronic instability shows a better proprioception in the acute group in the mid range position 6 months after the reconstruction.

Adult↗
PubMed2000

[Preoperative patient education. What is especially important?].

Any medical procedure must be legally authorized by the patient, giving informed consent. This prerequisite is based on the right to self determination. Otherwise a medical procedure is considered as physical injury. Thus, the way, how a specific procedure is performed, predominantly depends on the patient's will. The attending physician's duty is to find out this will, which is especially important when old patients and patients incapable of giving valid consent are involved. Before the procedure the physician has to have a confidential talk with the patient. He has to point out the best treatment possible considering the individual circumstances of the patient's life. The physician has to find out, weather the patient is competent to refuse or consent to treatment. Furthermore the consultation is an opportunity to diminish the patient's fear and to increase his confidence. The main problem treating old patients is that they often lack the mental ability for appreciation of the nature of the situation. One has to differentiate between the physiological mental decay and dementia or psychiatric diseases. In these cases a third party consent is necessary.

Aged↗
PubMed2000

Outcome analysis following open rotator cuff repair. Early effectiveness validated using four different shoulder assessment scales.

Evaluation of upper extremity function after reconstructive surgery is increasingly important both to predict outcome and for the control of cost-effectiveness. Three validated, self-administered shoulder questionnaires were applied prospectively in 23 otherwise healthy patients with rotator cuff deficiency and correlated to the Constant-Murley Shoulder Score and a visual analogue scale for satisfaction. Seven women and 16 men with combined tears of supraspinatus and infraspinatus (mean age 55.3 +/- 10.5 years, r/l: 14/9, follow-up 57.8 +/- 15.7 weeks) were gathered prospectively and evaluated pre- and postoperatively with the American Shoulder and Elbow Surgeons (ASES) Shoulder Index, the Simple Shoulder Test (SST) and the Disabilities of the Arm, Shoulder and Hand Module (DASH questionnaire). Additionally, a visual analogue scale for satisfaction was employed. All four scores and the visual analogue scale revealed improvement at a statistically significant level (P < 0.01) after surgery. All questionnaires showed a significant correlation with the Constant-Murley Shoulder Score (ASES: r = 0.871, P < 0.01; DASH: r = -0.758, P < 0.01, SST: r = 0.494, P < 0.05, Pearson's correlation coefficient). Taken together, all questionnaires were easy to apply, and reliable evaluation of shoulder function was possible with significant correlation to the Constant-Murley Shoulder Score postoperatively. The SST was easy to apply, and compound outcome analysis was possible with the ASES Shoulder Index and DASH questionnaire. The DASH scale was the most complex evaluation instrument. The Constant-Murley Shoulder Score comprises a physical examination, which is advantageous but restricts the application to the office. For postoperative assessment without the patient having to return to the clinic, the ASES Shoulder Index is preferred because of its good correlation to the Constant-Murley Shoulder Score (r = 0.871) and the visual analogue scale for satisfaction (r = 0.762).

Adult↗
PubMed2000

Proprioception after rehabilitation and reconstruction in knees with deficiency of the anterior cruciate ligament: a prospective, longitudinal study.

We assessed proprioception in the knee using the angle reproduction test in 20 healthy volunteers, ten patients with acute anterior instability and 20 patients with chronic anterior instability after reconstruction of the anterior cruciate ligament (ACL). In addition, the Lysholm-knee score, ligament laxity and patient satisfaction were determined. Acute trauma causes extensive damage to proprioception which is not restored by rehabilitation alone. Three months after operation, there remained a slight decrease in proprioception compared with the preoperative recordings, but six months after reconstruction, restoration of proprioception was seen near full extension and full flexion. In the mid-range position, proprioception was not restored. At follow-up, 3.7 +/- 0.3 years after reconstruction, there was further improvement of proprioception in the mid-range position. There was no difference between open and arthroscopic techniques. The highest correlation was found between proprioception and patient satisfaction. After reconstruction of the ACL reduced proprioception may explain the poor functional outcome in some patients, despite restoration of mechanical stability.

Activities of Daily Living↗
PubMed1999

[Nonunion of the humeral diaphysis - operative and nonoperative treatment].

Operative treatment of acute humeral shaft fractures represents a major source of nonunions. The analysis of the biomechanical and biological causes of diaphyseal nonunions of the humerus is a prerequisite for the successful treatment of ununited humeral shaft fractures. Biologically active nonunions heal after debridement and correction of deformities with an improvement of mechanical stability, preferably by fixation with a compression plate. In atrophic nonunions, the restoration of the biologic capacity to restore osteogenesis by bone grafting is additionally necessary. The treatment of synovial pseudarthrosis and infected nonunion requires removal of bone and debridement of synovial and infected avascular tissues, respectively. Intramedullary nails to improve mechanical stability and nonoperative treatment with extracorporeal shock waves should only be used in a few special cases which do not have any severe deformities.

Biomechanical Phenomena↗
PubMed1999

[Os trigonum syndrome].

The os trigonum syndrome is an entity causing posterior ankle pain and occurs mostly with typical sports activities. Diagnosis and differential diagnosis are presented. Typical complaints and therapeutic procedure are demonstrated in one case. Therapy includes different non-operative methods, resistance to non-operative procedures is an indication for excision of this ossicle.

Adolescent↗