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N F Friederich

Publications and source records attributed to N F Friederich.

31 records · Page 2Linked to original sources
PubMed1996

Recurrent acute hemarthrosis after anterior cruciate ligament reconstruction. Report of an unusual complication and a review of the literature.

Arthroscopic-assisted and endoscopic operative techniques have allowed for less and less restrictive postoperative rehabilitation programs after cruciate ligament reconstruction. Accelerated rehabilitation programs may, however, also provoke mechanical problems at the transplant-bone interface, as reports in the literature of loosened fixation devices and loosened or even fractured bone pegs with subsequent hemarthrosis and recurrent instability have shown. We describe the case of a patient who presented with recurrent acute hemarthrosis after anterior cruciate ligament reconstruction without additional trauma and without instability. However, the symptoms and signs were clearly related to the fixation method employed.

Adult↗
PubMed1996

Deep posterior knee pain caused by a ganglion of the popliteus tendon--a case report.

The most common causes of posterior and posterolateral knee pain (besides referred pain) are knee joint effusions, tendinitis of the hamstring tendons, Baker cyst (semi-membranous cyst), bursitis, meniscal pathologies such as tears and ganglions and lesions of the anterior cruciate ligament. Less common causes include popliteus and gastrocnemius tendinitis, arthrofibrosis after trauma, posterior cruciate ligament sprains, deep venous thrombosis and/or irritations of the common peroneal nerve. We present one patient with posterolateral knee pain after a minor contusion. Magnetic resonance imaging revealed a degenerated posterior horn of the lateral meniscus and a somewhat unclear polypoid structure in the intercondylar region. As the posterior component of the pain persisted even after an arthroscopic partial meniscectomy, an operative revision was performed. A small ganglion of the sheath of the popliteus tendon was found and excised. The patient was immediately relieved of his pain after this procedure. To our knowledge this is the first report concerning a ganglion of the sheath of the popliteus tendon causing posterior knee pain. A similar pathology of the popliteus tendon has been described earlier but at a different localisation (in the hiatus), simulating a parameniscal cyst.

Adult↗
PubMed1996

[Knee joint ligament reconstruction--indications, results].

Cruciate ligament injuries have increased in number in the last 10 to 20 years. Nonoperative treatment of ligament injuries about the knee joint has lost some of its popularity; however, there are only very few randomized prospective studies demonstrating that operative reconstructions of knee ligament injuries do have a positive effect on preventing late osteoarthritic changes. In contrast, one of the best studies recently published shows that there may even be some increased rate of osteoarthritis in reconstructed patients. Why this? The concept of the 'Envelope of Load Acceptance' may explain, why some of the patients who opt for a nonoperative treatment of cruciate ligament injuries do very well. They lower the load and frequency to the knee joint and diminish their activity level. Patients with successfully treated ligament lesions about the knee joint may wish to go back to their preinjury level and may want to reach their preinjury 'shell' of load acceptance [Scott Dye, 1995]; however, this may already be too much for their knees [physiological overload] and may eventually lead to the osteoarthritic changes about the knee joint. Careful consultation of each individual patient's case of knee ligament injuries is essential for the successful treatment, a treatment which may reduce the rate of osteoarthritis and reduce costs for the injured and the community.

Anterior Cruciate Ligament↗
PubMed1993

[Gonarthrosis after injury of the anterior cruciate ligament: a multicenter, long-term study].

UNLABELLED: In order to estimate incidence, severity and associated factors in the development of the degenerative arthritis of the knee following a cruciate ligament injury, a multicenter, longterm follow-up study was undertaken. The time interval between injury and follow-up exam was a minimum of 15 years (range 15-52 years). Extensive physical examination and radiographic analyses from four "Knee Centers" (Hospital for Special Surgery, New York; Orthopädische Klinik, Bruderholz; Orthopaedic and Arthritic Hospital, Toronto; Orthopaedic Department Wichita, Kansas) on 328 patients revealed that the best correlation to the degree of osteoarthritis could be found to the time of meniscectomy. All other operations (suture of cruciate ligament, intraarticular or extraarticular reconstruction) showed much less correlation to the severity of the degenerative arthritis found at the follow-up exam. IN CONCLUSION: Preservation of as much meniscus tissue as possible at the time of injury seems to be the best warranty for slowing down degenerative arthritis after cruciate ligament injury.

Adult↗
PubMed1993

Role of extra-articular procedure.

This article describes the 1993 role of extra-articular procedures in the treatment of anterior cruciate-deficient knees. Twenty years ago, most operative effort was concentrated on elimination of the pivot shift phenomenon. Newer operative reconstructions made most of the advantages attributed to extraarticular procedures (shorter operating room time, less soft tissue injury, shorter postoperative rehabilitation) no longer true.

Anterior Cruciate Ligament↗
PubMed1993

[Knee joint function and the cruciate ligaments. Biomechanical principles for reconstruction and rehabilitation].

Trauma to the knee joint with disruption of one or both cruciate ligaments will start a biological response: inflammatory reactions, neurophysiological changes due to disruption of afferent nerve endings, and biomechanical changes which will ultimately lead to instability (functional and mechanical) as well as to early degenerative changes. Treatment, whether operative or non-operative, has to be based on a sound knowledge of biological and biomechanical principles. Cruciate ligament graft positioning, fixation, pre-tensioning, operative technique for reconstruction, and rehabilitation will all have influence on each other. All these factors therefore have to be balanced to achieve good mid- to long-term results.

Anterior Cruciate Ligament↗
PubMed1992

[Clinical application of biomechanic and functional anatomical findings of the knee joint].

In order to study the functional anatomy of the knee joint, careful anatomical dissections were conducted on over 130 fresh-frozen cadaveric knee specimens. We found no evidence to support the two-bundle and three-bundle theories of cruciate ligament fiber patterns. The longest fibers in the anterior cruciate ligaments (ACL) measured 37 mm, and the longest in the posterior cruciate ligament (PCL), 41 mm. Cruciate ligament insertions follow a transition line on tibia and femur. Usually not all the fibers of the cruciate ligaments are taut at the same time. They are progressively recruited according to the biomechanical demands placed on them. Fibre recruitment in the ACL is from knee flexion to extension and in the PCL from extension to flexion. The concept of fiber recruitment was recently evaluated mathematically. As a working hypothesis, the knee joint can be looked upon as a biological realization of the crossed four-bar linkage, even in three dimensions. In vitro measurements have shown that correct graft placement in cruciate reconstructions is critical for knee biomechanics. Incorrect placement of grafts may lead to decreased range of motion and/or increased laxity. Distance changes of 3 mm between femoral origin and tibial insertion of a graft may lead to a 400% increase of graft preload and will thus easily reach published pull-out forces for some of the graft fixation methods (button = 248 N). Precise drill guides and isometers may be helpful in any operative technique (open, arthroscopic). Using the IKDC evaluation form and the KT-1000 arthrometer, our studies on 25 patients demonstrated a direct correlation between intraoperative graft tracking and the clinical outcome 2 years after operation. Biomechanical studies to investigate in vivo strain patterns of the anterior cruciate ligament and in vitro strain patterns of isometrically placed cruciate graft reconstructions showed that they did not reach critical fixation failure or graft rupture loads. The highest values were measured in Lachman and anterior drawer testing. In the 20-kg Lachman test the maximum load was 96 +/- 6 N. This was twice the maximum loads of any of the quadriceps exercises (40-50 N). With an isometrically placed graft, full active range of motion postoperatively and exercises with isolated or combined contractions of quadriceps and hamstring muscles will result in small graft loads. Postoperative immobilization with plaster and/or protection with braces may therefore become obsolete.

Anterior Cruciate Ligament↗
PubMed1989

Pelvic manifestations of diffuse idiopathic skeletal hyperostosis (DISH): are they clinically relevant?

This is a cross-sectional, case-controlled study on the clinical relevance of diffuse idiopathic skeletal hyperostosis (DISH) in relation to the pelvic girdle. Thirty-two rheumatology patients with DISH were compared with 35 dermatology control subjects in respect to the clinical parameters pain and passive hip joint motion in a standardized manner. There were no significant differences between the two groups, indicating no major clinical relevance of DISH in the pelvic region. In a second study, the radiographs of 23 DISH probands were compared blindly with 23 matched controls. The only significant difference was a much higher degree of severe juxtaarticular bone formation in DISH probands. The majority of these spurs proved to be asymptomatic and did not affect the range of passive hip joint mobility. DISH is a frequently seen, often radiologically very impressive phenomenon of little clinical relevance, at least in the pelvic area.

Aged↗
PubMedDate not supplied

[Preliminary results after multiple knee injuries with operative reconstruction of chronic posterior-lateral instabilities].

AIM: The operative treatment of posterior knee instability is a difficult problem and the literature does not offer methods as good as ACL reconstruction. METHODS: With a new operative approach the authors have attempted to improve the surgical procedure and the final outcome in terms of stability and function. To illustrate our clinical findings, 20 cases of chronic posterior-lateral knee instability were retrospectively reviewed following PCL reconstruction. We examined 5 women and 15 men. The average follow-up period was 14 months (6 - 24 months) and the average age was 30 (17 - 59) years. RESULTS: Subjectively all patients were satisfied with the surgical outcome and there were no intraoperative technical difficulties and no patient had a postoperative problem. The p.-a. instability measured at 20 degrees of knee flexion was preoperatively 11.7 mm, postoperatively 7.2 mm and 6.7 mm on the uninjured side. The Lysholm score was preoperatively 59 (35 - 71) points and postoperatively 85 (65 - 100) points. 19 patients returned to work and 14 patients were able to participate in sports. CONCLUSION: The results demonstrate that the knee still does not have a normal stability postoperatively, but the results were reproducible and the method appears to be reliable.

Adolescent↗
PubMedDate not supplied

Occurrence of free nerve endings in the soft tissue of the knee joint. A histologic investigation.

We present a comprehensive histologic study of neurologic structures in 18 static and dynamic knee structures of 8 cadaveric knees. Qualitative and quantitative measurements of the incidence of free nerve endings in the structures were recorded. The highest amounts of afferent nerve fibers type IVa were found in the retinacula, the patellar ligament, the pes anserinus, and in the ligaments of Wrisberg and Humphry; the lowest amount was found in the anterior cruciate ligament. There is a positive correlation between the number of mechanoreceptors per standardized area unit and the clinical presentation of certain knee disorders.

Anterior Cruciate Ligament↗
PubMedDate not supplied

[Validation of the Tekscan system for statistic and dynamic pressure measurements of the human femorotibial joint].

In vitro dynamic pressure measurements in the healthy and pathologically altered knee joint help to improve our understanding of the loading pattern on femorotibial surfaces. The aim of the study was to evaluate a piezoresistive pressure measuring system. A human cadaveric knee was mounted in a material-testing machine (Bionix 858) using a specially designed knee-holding device. Axial loading of the knee, flexed at 20o, at 500 N, 1000N and 1500 N was then carried out. For the static investigations, the piezoresistive measuring system (Tekscan), was compared with the FUJI measuring system. In addition, dynamic measurements were also performed with the Tekscan System. With the exception of the lateral compartment at a load of 1500 N, no differences in maximum pressures were observed between the two systems. Nor were there any differences with regard to contact surfaces, either in the medial or lateral compartment (p > 0.05). However, the reproducibility of the data was significantly higher with the Tekscan System (p < 0.01). Dynamic pressure measurements obtained with the knee flexed 20 to 90o showed that the lateral contact area shifted from anterior to posterior, while the medial contact area remained virtually unchanged. The Tekscan System proved to be more reliable than the FUJI System, and permits simultaneous measurements in both compartments. The Tekscan System is suitable for dynamic measurement of the femorotibial joint, and permits measurements to be made under more physiological conditions.

Aged↗