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R Schmidt-Wiethoff

Publications and source records attributed to R Schmidt-Wiethoff.

6 recordsLinked to original sources
PubMed2005

Bone plug length and loading angle determine the primary stability of patellar tendon-bone grafts in press-fit ACL reconstruction.

The present study was conducted to evaluate the influence of bone-plug length on the primary stability of patellar tendon-bone grafts, using a femoral press-fit fixation technique. Forty-eight human PTB grafts with a patellar bone-plug length of 15 mm and 25 mm were obtained from 24 human cadavers (mean age 72 years) and implanted to porcine femora in a press-fit fixation technique. Tensile loading was performed at 10 mm/s until failure at varying loading angles of 0 degrees, 30 degrees and 60 degrees. Compared to 25 mm, a significant decrease of primary graft stability was recorded in the testing of 15-mm bone plugs. For both plug lengths, the ultimate load to failure increased with rising the loading angles. While axial graft loading exclusively caused plug dislocation, the predominant mode of failure was tendon rupture at 60 degrees loading angle. We conclude that 15-mm bone plugs do not result in a sufficient stability for early aggressive rehabilitation and therefore 25-mm bone plugs are recommended for the femoral press-fit technique.

Aged↗
PubMed2004

Shoulder rotation characteristics in professional tennis players.

Aim of this study was to assess the glenohumeral joint internal and external rotational range of motion using an ultrasound based kinematic measurement device. Twenty-seven male professional tennis players were bilaterally measured for internal and external rotation at 90 degrees of shoulder abduction while avoiding scapulothoracic motion. The control group consisted of 20 asymptomatic volunteers not involved in overhead sports activities. The dominant arm (playing arm) had a significantly greater range of external rotation than the non-dominant arm, while their internal rotation showed a significant deficit as compared to the non-dominant arm. The dominant arm total rotational range of motion was also significantly reduced in comparison to the non-dominant arm and to the controls. No significant difference was found between the dominant and non-dominant extremity in the control group. For objective measurement of glenohumeral rotational range of motion ultrasound based real time motion analysis is a new application for the diagnostic testing of specific shoulder parameters in orthopedics and sports physical therapy. It is therefore concluded that the specific methodology aiming at isolated glenohumeral motion may have clinical application for the development of rehabilitation and preventative programs.

Adult↗
PubMed2002

[Physical activity after shoulder arthroplasty].

A hemi- or total shoulder arthroplasty was performed in 171 patients between 1992 and 1997. We examined 118 patients under the age of 70 regarding their level of physical activity. For a pre- and postoperative comparison we divided the patients in two groups. Group one included all patients with osteoarthritis, rheumatoid arthritis, instability associated arthritis, avascular necrosis and other arthropathies. Group two included acute fractures and fracture sequelae. The postoperative outcome was functionally assessed by using the Constant score. There was an average Constant score of 60,9 for group one and 67,1 for group two. Both groups showed a domination of activities with motion patterns unspecific for the shoulder. There were more patients in group two reporting activities which depend on a good or very good shoulder function. There is no general estimation for the ability to be active in sports after shoulder arthroplasty. An individual assessment of the shoulder function is essential. Important criterias beside motivation and age are the status of the rotator cuff and the soft tissue balancing. The correct indication for shoulder arthroplasty as well as the preoperative planning and the postoperative rehabilitation program are essential for a good functional outcome and the key for physical activity after shoulder arthroplasty.

Adult↗
PubMed1996

[Diagnosis and therapy of shoulder instability].

Shoulder instability is based on various acquired or constitutional aspects which determine the therapy and clinical outcome. In order to differentiate between traumatic and atraumatic forms of shoulder instability a careful history has to be taken. A systematic clinical examination is necessary to evaluate the shoulder joint for general laxity or true instability and especially to assess direction and degree of glenohumeral translation. The basic diagnostic imaging includes X-rays in 3 planes. CT-arthrogram and MRI may provide additional information to evaluate the intraarticular pathology. An elective therapy depends on the patients age and demands. Recurrent anterior dislocations are treated by an anatomical reconstruction of the glenohumeral ligament complex. Open or arthroscopic Bankart-repair have been established as the treatment of choice. Conservative treatment is primarily indicated in cases of atraumatic posterior or multidirectional instability. If physiotherapy fails, surgical treatment should be discussed for these patients.

Diagnosis, Differential↗
PubMedDate not supplied

[Shoulder arthroplasty - Clinical results in 171 patients].

AIM: Review and critical evaluation of 181 shoulder arthroplasties performed on 171 patients between December 1992 and January 1997. METHOD: We performed 118 hemiarthroplasties and 63 total shoulder replacements in 171 patients with an average age of 56.5 years. The patients were examined clinically and radiologically before surgery and followed-up for an average of two years. The Constant score was used for postoperative functional assessment. RESULTS: 46 % of the patients were very satisfied and 31 % were satisfied with the outcome. We found a significant pain reduction and an improvement of active joint function. The average Constant score was 34.9 preoperatively and 65.2 postoperatively. Overall, we found the best results after joint replacement in patients treated for avascular necrosis or fracture sequelae of the humeral head. A revision surgery had to be performed in 16 patients (8.8 %). CONCLUSION: The results of this study are encouraging and underline the growing importance of shoulder arthroplasty. The preoperative limited range of motion, previous surgeries, and the status of the rotator cuff are preoperative indicators for a favourable postoperative outcome. Preoperative planning, anatomical reconstruction, and an optimal rehabilitation programme are the keys for successful shoulder arthroplasty.

Adult↗