Biomedical subjects

H Bäthis

Publications and source records attributed to H Bäthis.

36 records · Page 2Linked to original sources

PubMed2004

[Accuracy of an image-free cup navigation system--an anatomical study].

The position of the acetabular cup is of decisive importance for the function of a total hip replacement (THR). Using the conventional surgical technique, correct placement of the cup often fails due to a lack of information about pelvic tilt. With CT-based and fluoroscopically-assisted navigation procedures the accuracy of implantation has been significantly improved. However, additional radiation exposure, high cost and the increased time requirement have hampered the acceptance of these techniques. The present anatomical study evaluates the accuracy of an alternative procedure--image-free navigation. This method requires little extra effort, does not substantially delay surgery, and needs no additional imaging. Press-fit cups were implanted in 10 human cadaveric hips with the help of the image-free navigation system, and the position of the cups was checked intraoperatively with a CT-based navigation system and postoperatively by computed tomography. All cups were implanted within the targeted safe zone with an average inclination of 44 degrees (range 40 degrees-48 degrees, SABW 2.7 degrees) and an average anteversion of 18 degrees (range 12-24 degrees, SABW 4.1 degrees). Analysis of accuracy of the image-free navigation software revealed only a small, clinically tolerable deviation in cup anteversion and cup inclination in comparison with the CT-based navigation system and the post operative CT scans. The evaluated image-free navigation system appears to be a practicable and reliable alternative to the computer-assisted implantation of acetabular cups in total hip arthroplasty.

Acetabulum↗

PubMed2003

[CT-based and CT-free navigation in knee prosthesis implantation. Results of a prospective study].

INTRODUCTION: Accurate leg alignment is one important factor for long-term survival in total knee arthroplasty (TKA). The classical surgeon-controlled technique is associated with a deviation of the leg axis of more than 3 degrees in up to 30% of cases, regardless of the surgeon's experience. The aim of this study was to test the efficiency of a CT-based and CT-free navigation system in restoration of the leg axis. METHOD: 100 TKA (PFC-Sigma, DePuy) were implanted either using the CT-based or CT-free module of the Vector-Vision navigation System (BrainLAB). There were no significant differences between the groups in preoperative leg deformity. Accuracy of implantation was determined on postoperative long-leg coronal and lateral X-rays. RESULTS: A postoperative leg axis between 3 degrees varus and 3 degrees valgus was obtained in 46 patients (92%) in the CT-based group (A) and in 48 patients (96%) in the CT-free group (B). No significant differences were found for varus / valgus orientation (+/-3 degrees ) of the femoral (A=96%; B=94%) and tibial (A and B each 98%) components. CONCLUSION: The use of the CT-based and CT-free Vector-Vision system allows a significant improvement in the accuracy of implantation in TKA. The CT-based module has the advantage of precise preoperative planning. On the other hand there are additional costs and time-consuming logistics. The advantages of the CT-free module are the intraoperative visualisation of the leg axis, the ligament balancing and joint kinematics. Cutting errors can be detected and corrected with both modules.

Adult↗

PubMed2003

[Innovations in total knee arthroplasty].

The development of total knee arthroplasty started in the fifth decade last century. Modern total knee joint systems represent a high grade of modularity for a usage within the whole range of joint destruction situations, such as for rheumatoid arthritis. Innovations for improved long term survival can be seen in methods reducing aseptic loosening, such as new implant materials or mobile platforms. Moreover improved surgical techniques for precise component orientation and reconstruction of a neutral leg axis have been introduced using computer assisted surgery. So far the results using this technique are very promising. Long term results are not yet available.

Arthroplasty, Replacement, Knee↗

PubMed2003

[Useability of an image based nagivation system in reconstruction of leg alignment in total knee arthroplasty - results of a propsective study].

Accurate leg alignment is one important factor for long term survival in total knee arthroplasty (TKA). The aim of this study was to determine the accuracy of a CT-based navigation system in restoration of the leg axis. 80 TKA (P.F.C.-Sigma--DePuy) were implanted either using a CT-based navigation-system or the conventional technique. There were no significant differences between the groups according to the preoperative leg deformity. Accuracy of implantation was determined on postoperative long-leg coronal and lateral x-rays. A postoperative leg axis between 3 degrees varus and 3 degrees valgus was obtained in 35/40 patients (88%) in the computer assisted and 28/40 patients (70%) in the conventional operated group. A higher precision in the sagittal plane was seen for the tibial (computer assisted: 3.9 +/- 2.2 vs. conventional TKA 1.3 +/- 5.8) and the femoral component (computer assisted: 3.5 +/- 2.3 vs. conventional TKA 6.9 +/- 3.6). The use of the CT-based VectorVision-System allows a significant improvement in the accuracy of implantation in TKA. The CT-based module has the advantage of a precise preoperative planning and a useful documentation and control tool for each important step. On the other hand there are additional costs and time consuming logistics.

Adult↗

PubMed2001

[The displaced proximal humeral fracture: is there evidence for therapeutic concepts?].

INTRODUCTION: There is no general agreement on the operative treatment of displaced proximal humeral fractures. While T-plate fixation was the method of choice until the end of the 1980s, minimally invasive techniques have been favoured during the past decade. The indication for primary shoulder prosthesis is controversial. The purpose of this report was to evaluate the scientific evidence of current treatment recommendations. METHODS: Relevant articles were retrieved from "Medline" and "Knowledge-Finder" using the combined search strategy for the keywords "proximal humerus" and "fracture". Retrieved articles were evaluated according to the criteria of evidence-based medicine. RESULTS: The analysis retrieved 3 randomized, 4 prospective, and 26 retrospective studies and a number of review articles relevant to the subject. Limitations of most publications were due to small study populations, differences in patient selection and fracture classification as well as measurements of outcome. According to these studies good functional results can be achieved in dislocated two-part fractures treated with minimal osteosynthesis in the elderly and T-plate fixation in younger patients. For three- and four-part fractures minimally invasive techniques seem to be more favourable in the elderly. However, there is some evidence that alternative therapies such as conservative treatment and plating can be successful in defined populations. A general indication for primary implantation of a prosthesis in four-part fractures in the elderly is not supported by the literature. CONCLUSION: We conclude from our analysis that the scientific evidence for treatment recommendations of displaced proximal humeral fractures is still limited.

Adult↗

PubMed2001

[Therapy of traumatic anterior shoulder dislocation: current status of therapy in Germany. Are there scientifically verified therapy concepts?].

There are no generally accepted concepts for the treatment of traumatic anterior shoulder dislocation. The objective of this study was to ascertain the current treatment for traumatic shoulder dislocations in German hospitals and to compare this with the data reported in the literature. A total of 210 orthopedic surgery departments were asked for their treatment strategy in an anonymous country-wide survey; 103 questionnaires (49%) were returned for evaluation. Additional imaging (ultrasound, CT, MRI) beyond the routine X-rays is performed in 82% of clinics for primary shoulder dislocation (94% in recurrent dislocation). A young, athletic patient (< 30 years old) would be operated on for a primary traumatic shoulder dislocation in 73% of hospitals (98% in recurrent dislocation). In contrast, a patient of the same age, with a moderate level of sporting activity would be treated conservatively in 67% of cases (14% in recurrent dislocation). Similarly, for an active, middle-aged patient with a demanding job, 74% of responses favored conservative treatment after a primary dislocation and 6% after a recurrent dislocation. Older patients (> 65 years old) are usually treated conservatively after a primary or recurrent shoulder dislocation (99%, 69%). For a primary shoulder dislocation the most popular surgical reconstruction is a Bankart repair (75%). For recurrent shoulder dislocation several different operative techniques are seen (Bankart 29%, T-shift 26%, Putti-Platt 8%, Eden-Lange-Hybbinette 22%, Weber osteotomy 13%). Based on our literature review, we found: (1) The clinical examination of both shoulders is important to diagnose hyperlaxity; (2) Routine CT or MRI is not necessary for primary traumatic shoulder dislocations; (3) A young, athletic patient should undergo surgical reconstruction after a primary shoulder dislocation; (4) The operation of choice for primary and recurrent dislocation is the Bankart repair; (5) There is no sufficient evidence that an arthroscopic Bankart repair is as good as an open procedure; (6) There are limited indications for other operative techniques, as they are associated with a higher recurrence and arthrosis rate.

Adolescent↗

PubMed2001

[Constant Score and Neer Score. A comparison of score results and subjective patient satisfaction].

INTRODUCTION: The Constant- and the Neer-Score are widely used to assess shoulder function after trauma or shoulder diseases. The objective of this study was to compare the correlation of score result with the patient subjective assessment. We hypothesized that there is a clinically relevant difference between the score result and the patient assessment, especially for highly selective patient groups. METHODS: 51 patients were followed up after the surgical treatment of a proximal humeral fracture. For each patient the Constant- and the Neer-Score was calculated. Further, the patients were asked for a subjective assessment of their shoulder function ("excellent", "good", "fair", "poor"). RESULTS: For both score-systems a good linear correlation (r = 0.97) is shown. 57% of the patients assessed their shoulder function as "excellent" or "good", but only 37% (Constant) vs. 43% (Neer) of the patients were classified as "excellent" or "good" based on their score results. The Spearman correlation of subjective and score-based assessment was just fair with r = 0.50 (Constant) and r = 0.55 (Neer). When comparing the score results with the patient subjective assessment for the groups: "excellent", "good", "fair" and "poor", there was a positive correlation for the Neer-Score in 20 cases and for the Constant-Score in 15 cases. Of all elderly patients (> 60 years, n = 20), 14 (Neer-Score) vs. 16 (Constant-Score) assessed their shoulder function as better than the score did. CONCLUSION: The hypothesis of a clinically relevant difference between the subjective and the score-based assessment of shoulder function can be confirmed. Our results suggest that for clinical practice, statements and therapy strategies recommended in the literature, that are just based on score results might not be valid for all patient-groups (e.g. elderly patients).

Adolescent↗

PubMed2001

[The status of therapy of acromioclavicular joint injury. Results of a survey of trauma surgery clinics in Germany].

The therapy of acromioclavicular dislocations remains controversial. In particular, for injuries classified as Rockwood/Tossy Type III good results have been reported with different operative techniques as well as with conservative treatment. The objective of this study was to obtain data about the current treatment for Rockwood/Tossy III injuries in German trauma departments. In a countrywide anonymous survey 210 German trauma departments were asked about their diagnostic procedures and their treatment strategies for acromioclavicular injuries. 104 questionnaires (49%) were returned and evaluated. In Rockwood/Tossy I/II injuries most clinics recommend conservative treatment (Rockwood/Tossy I/II: 99%/87%). On the other hand, 84% of the clinics would operate on Type III acromioclavicular injuries--especially in athletes or overhead workers. Although 38 percent of the clinics believe that conservative treatment is equal or better than operative treatment, only 13 percent manage Type III injuries conservatively. For more severe acromioclavicular injuries (Rockwood IV to VI) all clinics recommend an operative treatment. The operative techniques of choice for acromioclavicular injuries are K-wire fixation (37%) or a coraco-clavicular cerclage (32%). Of the latter, 73% use a resorbable material, while the remainder use wires.

Acromioclavicular Joint↗

PubMed2001

[Surgical therapy of traumatic shoulder dislocation. Are there evidence-based indications for arthroscopic Bankart operation?].

INTRODUCTION: For young athletic patients with a primary traumatic shoulder dislocation a surgical treatment is recommended. The operation of choice is the Bankart-Repair. QUESTION: Are there evidence-based indications for an arthroscopic Bankart repair. METHODS: Based on the criteria of the "Cochrane Collaboration" a systematic literature search was performed using medline (1966 to 9/2000). 172 publications were found with the key words "shoulder dislocation" and "Bankart". All relevant articles were ranked and analysed by the criteria of "evidence-based medicine". RESULTS: There are 12 prospective studies (evidence grade Ib/IIa) and another 28 retrospective studies (evidence grade III). For open Bankart-Repair a recurrence rate of 0 to 8% is reported (prospective/retrospective studies). For arthroscopic Bankart-Repair, 19 of 40 studies and 8 of 12 prospective studies, show a recurrence rate of < 10%; however in other studies (prospective/retrospective) an atraumatic recurrence rate of up to 38% is reported. The reasons for these differences in the recurrence rate are not obvious from the given data. In particular, there seems to be no correlation between the type of arthroscopic fixation technique and the recurrence rate. Concerning the postoperative range of shoulder motion, the reported data suggest that external rotation is less limited after arthroscopic than after open Bankart-Repair (arthroscopic: 5-12 degrees, open: 5-25 degrees). However, there is no evidence that patients are more likely to return to their previous level of sporting activities when operated on in an arthroscopic technique than in an open technique (arthroscopic: 42-100%, open: 72-94%). CONCLUSION: In the surgical treatment of a traumatic shoulder dislocation, the open Bankart-Repair remains the "gold standard". In reviewing the literature, arthroscopic Bankart-Repair has not been shown to be equal or superior to the open technique.

Arthroscopy↗

PubMed2001

[Therapeutic concept for preventing chronic phantom pain after traumatic brachial plexus lesion].

We report on a 29-year-old motorcyclist, who had suffered a traumatic right side arm plexus lesion. The myelo-CT image showed a avulsion of the cervical roots C7/C8. Five days after the accident the patient complained of phantom pain in the right plegic arm and was presented to our acute pain service (APS). The patient complained of lancinating attacks of severe phantom pain in the right arm (visual analogue scale intensity of 80-100 pts.). The initial pain treatment was performed with PCA (piritramide), and because of the lancinating pain character carbamazepine treatment was introduced. The pain intensity increased under carbamazepine (VAS = 100 pts.), and after treatment with five cycles of salmon-calcitonin infusion the pain intensity decreased (VAS = 10 pts). After withdrawal of the infusion therapy with salmon calcitonin the pain intensity increased up to VAS = 70 pts. TENS therapy five times per day showed no analgetic effect. We repeated the calcitonin-infusion therapy and after five i.v. cycles we continued with 200 I.U. salmon calcitonin intranasal per day. The initial phantompain intensity decreased (VAS = 40 pts.), but showed no long term analgesia. The additional psychological treatment with relaxation techniques (Jacobson/Bensen) showed the desired phantom pain relief. An interdisciplinary and multimodal cooperation between anesthesiologists, trauma surgeons, neurosurgeons and psychologists is needed for successful phantom pain treatment after traumatic brachial plexus lesion. Intravenous salmon calcitonin showed only short-term analgetic effect.

Adult↗

PubMed2001

[Surgical treatment of proximal humeral fractures. Is the T-plate still adequate osteosynthesis procedure?].

No general agreement exists on the operative therapy of displaced proximal humeral fractures. The purpose of this study is to evaluate different internal fixation techniques (plate fixation, figure-of-eight tension wiring, lagscrew) and to verify if the plate fixation is still an adequate therapy in the treatment of displaced proximal humeral fractures. A follow-up investigation was conducted in 51 patients after an average of 4.2 years. A T-plate fixation was performed in 62.7%, a minimal invasive technique in 21.6% and a shoulder prosthesis in 15.7% of these patients. At follow-up 60.7% of the patients with a 3- or 4-part fracture had good or excellent results in the Constant score (59% T-plate, 66% minimal invasive). Humeral head necrosis was seen in 15.9% of the patients with a T-plate fixation and in 9.1% of the patients with minimal invasive techniques. Based on our results and the reviewed literature we can confirm advantages of the minimal invasive techniques in the treatment of 4-part fractures. However, good results can be obtained with T-plate fixation in 2- or 3-part fractures especially in younger patients.

Age Factors↗

PubMed2000

[Conservative or surgical therapy of acromioclavicular joint injury--what is reliable? A systematic analysis of the literature using "evidence-based medicine" criteria].

There is controversy about the therapy for third-degree acromioclavicular dislocation according to Tossy and Rockwood's classification. Both operative and non-operative treatment is reported to have satisfactory results in the literature. The purpose of this study was to analyze the literature in a systematic manner based on the criteria of evidence-based medicine. It was our hypothesis that there is no scientific evidence for the superiority of one treatment over the other. A total of 370 papers were retrieved and classified into three groups: (1) randomized controlled trials; (2) comparative retrospective studies; and (3) retrospective studies. In three studies that were graded with high evidence, the major outcome for both operative and non-operative treatment was similar. The advantages of non-operative treatment include a shorter period of rehabilitation and a significantly lower complication rate while the advantages of operative treatment include a low rate of persisting subluxation of the AC joint. Similar results were found for retrospective comparative and long-term studies. For retrospective studies without controls, both operative and conservative therapy are described with good and excellent results, ranging between 80 and 97%. In conclusion, there is good evidence on the therapy of third-degree acromioclaviculary dislocation studies. The functional result according to the literature is similar, and complications associated with therapy occur more often with operative treatment. Conservative treatment appears to be the method of choice for third-degree acromioclavicular dislocations unless the patient's preference is operative therapy.

Acromioclavicular Joint↗

PubMed2000

[Dorsal carpometacarpal dislocation of the fifth finger: discussion of diagnosis and therapy on two cases].

Dorsal dislocation of the fifth carpometacarpal joint after injury is rare. Only five cases are reported in the literature. We report on two cases of dorsal dislocation of the fifth carpometacarpal joint after injury and we give a review of related literature. There are two interesting aspects concerning diagnostic and therapy of dorsal dislocation of the fifth carpometacarpal joint. Anterior-posterior and lateral radiographs do not always provide adequate visualisation of this joint so a dislocation may be misdiagnosed. A radiograph taken with the forearm pronated 45 degrees from the routine anterior-posterior position better shows the dislocation. The adequate therapy consists in closed reduction, Kirschner wire fixation and cast immobilisation. A reduction without following Kirschner wire fixation - even in those dislocations that were found to be stable after closed reduction - is not recommended because of the risk of persisting pain after heavy manual work. In our two cases an instability of the fifth carpometacarpal joint existed after closed reduction. After Kirschner wire fixation and cast immobilisation for 6 weeks both patients showed 3 months after operative therapy a full range of movement and a powerful grip without any pain in the fifth carpometacarpal joint.

Adult↗

PubMed2000

[Non-Hodgkin lymphoma as differential spondylodiscitis diagnosis].

This case presents the history of a 56-year-old patient suffering from low back pain for a period of several weeks. The radiological und histopathological examination showed hints for a spondylodiscitis of the fifth lumbar vertebra. Due to a progressive destruction of the fifth vertebra a ventral stabilisation was performed. Again the histological examination showed the characteristics of an unspecific spodylodiscitis. The last biopsy, taken during the explantation of the fixateur interne showed a high malignant lymphoma. A course of chemotherapy was started following the CHOP-Protocol accompanied by radiotherapy. This case demonstrates that meticulous clinical examination as well as advanced radiological techniques can fail in rare differential diagnosis of spondylodiscitis.

Diagnosis, Differential↗

PubMedDate not supplied

[Tissue toxicity of antiseptics].

AIM: Local antiseptics are used for desinfection of skin and for lavage of wounds. The aim of this study was to determine the tissue toxicity of different antiseptics and to measure the irritation score (IS) and the irritation threshold (IT) for each substance. METHOD: The tissue compatibilities of Dibromol, Kodan, Jodobac, Octenisept, Lavasept 0.2 %, hydrogen peroxide, chlorhexidindigluconate 0.5 % and 2-propanol 60 % were evaluated in the in vivo hens eggs chorion-allantoic membrane test (HET-CAM). RESULTS: We found the most severe tissue toxicity for chlorhexidin digluconate 0.5 % (IS 20) and Kodan (IS 18). Irritating values were found for Dibromol (IS 14), Octenisept (IS 14) and 2-propanol 60 % (IS 13). Moderate vascular injuries were caused by Jodobac (IS 2). In the HET-CAM test Lavasept 0.2 % (IS 0) and hydrogen peroxide (IS 0) showed no tissue toxicity. CONCLUSION: Our results show that some of the tested antiseptics might cause severe vascular injuries as a sign of tissue toxicity. The tissue compatibility of Lavasept 0.2 % and hydrogen peroxide is much better than the compatibility of the other tested substances. With focus on the literature and our results, Lavasept 0.2 % can be recommended as the local antiseptic of choice.

Allantois↗

PubMedDate not supplied

[Total knee arthroplasty and high tibial osteotomy in osteoarthritis--results of a survey in traumatic surgery and orthopedic clinics].

AIM: Knee arthroplasties, both total (TKA) and unicondylar, as well as high tibial osteotomy (HTO) represent the main treatment options in severe osteoarthritis of the knee. The aim of this study was to collect detailed information regarding the current treatment strategies in Germany. METHODS: 220 departments of orthopaedic surgery and 250 departments of trauma surgery were asked about their treatment strategies in an anonymous nation-wide survey regarding the different operative procedures in HTO, TKA, revision TKA and related issues. Univariate analyses were performed and means, medians and rates were calculated. RESULTS: Questionnaire forms were answered by 54 % of the departments. The survey represents 31 138 TKA for the year 2002. In the mean 137 TKA were performed in each department. Posterior cruciate ligament retaining components were used in 67 %, resurfacing of the patella was performed in 19 % of cases. The incidence of revision TKA is about 10 % compared to the primary TKA cases. In comparison to a different survey from the year 1995, the absolute number of primary and revision TKA has increased by a factor of nearly three. Compared to the number of TKA, the proportion of HTO has declined to 12 % and the number of unicondylar knee arthroplasties represents 7 % of all cases. CONCLUSION: In the surgical treatment of severe osteoarthritis, TKA shows a highly increasing number, whereas HTO is decreasing. An increasing number of revision TKA can be observed. There is trend towards the cemented implantation technique. Patella resurfacing is not performed routinely in most German hospitals.

Arthroplasty, Replacement, Knee↗

PubMedDate not supplied

[Current treatment modalities for cartilage defects at the knee--results of a nation-wide survey of surgical trauma and orthopaedic clinics in Germany].

AIM: A local cartilage defect at the knee is mostly followed by arthritis after a period of time. Up to now there are no options to adequately regenerate hyaline cartilage in vivo. Hence, the present strategies try to create a repair tissue with hyaline-like characteristics or to repair defects by transplanting autologous osteochondral cylinders. The objective of this study was to collect data about the current treatment of local cartilage defects of the knee in Germany. METHOD: In a countrywide anonymous survey, 250 German trauma surgery and 220 orthopaedic surgery departments were asked about their diagnostic procedures and their treatment strategies when addressing a local cartilage defect of the knee. RESULTS: 230 (48.9 %) of the questionnaires were returned and evaluated. We found differences between the two specialities: the orthopaedic departments are more progressive in applying autologous chondrocyte transplantation (ACT) (28.3 % versus 13.6 %) and osteochondral transplantation (OCT) (69.1 % versus 56.3 %). Only 5.2 % of the German surgeons perform periostal grafting for local cartilage defects. CONCLUSION: There are still discrepancies about the therapy for local cartilage defects of the knee. Our survey illustrates the present status of cartilage repair strategies in Germany.

Cartilage↗

PubMedDate not supplied

[Therapy of femoral head osteonecrosis: results of a national survey].

AIM: The therapy for osteonecrosis (ON) of the femoral head is controversially discussed in the literature. The aim of this study was to ascertain the current treatment concepts of ON in Germany and to compare them with the results reported in the literature. METHODS: 219 Departments of Orthopedic Surgery were asked for their treatment strategies in an anonymous country-wide survey regarding the etiology, diagnosis and therapy (conservative, operative) of ON. Univariate analyses were performed and means, medians and rates were calculated. RESULTS: 43 % of ON were idiopathic, 28 % were due to alcoholism and another 17 % were seen after steroid intake. All departments performed biplanar X-rays for diagnosis of ON and 78 % of departments obtained additional magnet resonance imaging. In the early stages of ON (stage I, II) 33 % of orthopedic clinics recommend a conservative treatment (protected weight bearing, high energy shock wave, pulsed electromagnetic fields) while 67 % prefer surgery (79 % core decompression, 15 % flexion osteotomy, 6 % total hip arthroplasty). In the later stages (stage III, IV) most clinics perform an operative treatment (11 % core decompression, 10 % flexion osteotomy, 79 % total hip arthroplasty). CONCLUSION: Results of ON of the femoral head are unsatisfactory after protected weight bearing. No randomized clinical trials and no mid-term results are available for high energy shock wave or pulsed electromagnetic fields therapy. In the early stages of ON core decompression shows good results. However, in he later stages with secondary arthritis of the hip, total hip arthroplasty remains the gold standard.

Femur Head Necrosis↗