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Thorsten M Seyler

Publications and source records attributed to Thorsten M Seyler.

16 recordsLinked to original sources
PubMed2007

Gait analysis of patients with resurfacing hip arthroplasty compared with hip osteoarthritis and standard total hip arthroplasty.

Patients with standard total hip arthroplasties may have reduced hip abduction and extension moments when compared with normal nonosteoarthritic hips. In comparison, patients after resurfacing total hip arthroplasty appear to have a near-normal gait. The authors evaluated temporal-spatial parameters, hip kinematics, and kinetics in hip resurfacing patients compared with patients with unilateral osteoarthritic hips and unilateral standard total hip arthroplasties. Patients with resurfacing walked faster (average 1.26 m/s) and were comparable with normals. There were no significant differences in hip abductor and extensor moments of patients with resurfacing compared with patients in the standard hip arthroplasty group. This study showed more normal hip kinematics and functionality in resurfacing hip arthroplasty, which may be due to the large femoral head.

Adult↗
PubMed2006

Surgical treatment and customized rehabilitation for stiff knee arthroplasties.

UNLABELLED: Treating patients who have arthrofibrotic or stiff knees after total knee arthroplasty can be difficult. Treatment with arthroscopic débridement, arthrolysis of adhesions with polyethylene spacer exchange, or complete revision arthroplasty often has led to less than optimal range of motion and functional outcomes. We used a combination of surgical arthrolysis and an intensive postoperative rehabilitation protocol, including functional bracing, to treat this condition. We then retrospectively reviewed 18 knees in 17 patients who had stiff knees after total knee arthroplasty with no other detectable clinical or radiographic abnormalities, at a mean followup of 30 months. Seventeen knees (94%) had gains in knee range of motion with a mean increased range of motion of 31 degrees. Although 16 of 17 patients had clinical improvement and were satisfied with the procedure, only (2/3) of the patients (12 of 18 patients) had excellent or good Knee Society objective scores. This combined surgical and rehabilitation method can lead to an increased range of motion. All patients improved clinically, but good functional results were less predictable. The authors think treatment of these difficult knees should be aimed at soft tissue operative releases supplemented by an intensive rehabilitation protocol. LEVEL OF EVIDENCE: Therapeutic study, level IV (prospective study). See Guidelines for Authors for a complete description of levels of evidence.

Adult↗
PubMed2006

Minimally invasive revision total knee arthroplasty.

UNLABELLED: Exposure in revision total knee arthroplasty can be difficult. For example, eversion of the patella may require a number of procedures including vastus snips, V-Y turndowns, and tibial tubercle osteotomies. A minimally invasive approach further adds to exposure difficulties. We report a new approach for exposure during difficult revision total knee arthroplasties. A soft tissue envelope technique allows retraction of the patella and avoids eversion. This technique reduces the size of the incision, reduces quadriceps muscle damage, and enhances exposure. It is essential that appropriate instrumentation is used along with down sized femoral and tibial cutting blocks. We report all 17 revision knee arthroplasties using this technique including unicompartmental revisions, tibial component revisions, and femoral component revisions. Followup averaged 29 months (range, 24-39 months). We had one case of posterior retained cement after a full revision with no subsequent complications. One patient required an arthroscopic lateral release for patellar maltracking. Preliminary results are encouraging using improved instrumentation we find essential for enhanced exposure. We believe this a reasonable approach for selected total knee arthroplasty revisions. LEVEL OF EVIDENCE: Therapeutic study, level IV (retrospective case series). See the Guidelines for Authors for a complete description of levels of evidence.

Aged↗
PubMed2006

Bisphosphonate-associated arthritis.

We present a case of arthritis apparently induced by the administration of intravenous bisphosphonates in a 51-year-old white woman with metastatic breast carcinoma. She presented with bilateral knee pain and effusions on 2 separate occasions after receiving aminobisphosphonates. Synovial fluid analysis was negative for infection, metastasis, or crystals. Her symptoms resolved after the medication was discontinued and recurred after the patient was rechallenged with a medication from the same drug class. The administration of aminobisphosphonates has been associated with an acute-phase response in several in vivo studies. The mechanism of action is thought to be that aminobisphosphonates transiently stimulate the production of proinflammatory cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor-alpha. Rheumatologists should be aware of this possible cause of arthropathy.

Arthritis↗
PubMed2006

Uncemented total hip arthroplasty in young adults with osteonecrosis of the femoral head: a comparative study.

BACKGROUND: The outcome of uncemented total hip arthroplasty in patients with osteonecrosis of the femoral head in general, and in young adults in particular, remains largely unknown. This study evaluated the clinical and radiographic results of uncemented total hip arthroplasty in young adults with osteonecrosis of the femoral head and compared these results to those seen in young adults with osteoarthritis. METHODS: Forty-one consecutive patients with osteonecrosis of the femoral head (fifty-two hips) and forty patients with osteoarthritis (fifty-two hips) were treated with an uncemented total hip arthroplasty at our institution. The mean age for the osteonecrosis group was thirty-eight years, and, for the osteoarthritis group, forty-two years. Clinical and radiographic outcomes at a minimum of two years were assessed. RESULTS: At a mean duration of follow-up of three years, the functional improvement was significant in both groups (p < 0.05). The outcome was good to excellent for 94% (forty-nine hips) in the osteonecrosis group and 96% (fifty hips) in the osteoarthritis group. There were two revisions in the osteonecrosis group and one revision in the osteoarthritis group. Survivorship free of revision at the time of the latest follow-up was 96.1% for the osteonecrosis group and 98% for the osteoarthritis group. CONCLUSIONS: The short-term results of cementless total hip arthroplasty in patients with osteonecrosis of the femoral head were encouraging and comparable with the results of a matched group of patients with osteoarthritis. We await further follow-up to see if these promising results hold true. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Adolescent↗
PubMed2006

Osteonecrosis of the knee after laser or radiofrequency-assisted arthroscopy: treatment with minimally invasive knee arthroplasty.

BACKGROUND: Osteonecrosis of the knee after various arthroscopic procedures associated with the use of laser or radiofrequency devices has been described in a few case reports. The purpose of this study was to report on a series of nineteen patients with osteonecrosis of the knee after arthroscopic procedures. A literature search was done to compare this series of patients to previously reported cases. In addition, we analyzed the outcome after treatment with minimally invasive knee arthroplasty. METHODS: We studied patients who had development of osteonecrosis of the knee after a routine arthroscopic procedure. Preoperative and postoperative clinical notes, radiographs, and magnetic resonance images of patients were analyzed. Only those patients with no evidence of osteonecrosis on preoperative magnetic resonance imaging who later had development of osteonecrosis and subsequently required a knee arthroplasty were included. We conducted a search of the current literature to compare the results seen in our patient population with those seen in other patients with this entity. Patients were followed both clinically and radiographically for a mean of sixty-two months. RESULTS: A total of nineteen patients met the inclusion criteria. There were fourteen women and five men with a mean age of sixty-nine years. Six patients underwent an arthroscopy with associated holmium or yttrium-aluminum-garnet laser treatment, ten patients had associated radiofrequency treatment, and three patients had microfracture surgery. Subsequent arthroplasty procedures included four unicompartmental knee arthroplasties and fifteen tricompartmental knee arthroplasties. At the time of final follow-up, the mean Knee Society objective score was 95 points. CONCLUSIONS: Arthroscopic procedures may play a role in the development of osteonecrosis of the knee. To our knowledge, this is the largest series of patients to have development of this condition after arthroscopy with associated laser, radiofrequency, or microfracture surgery. The midterm results of knee arthroplasty in this unique patient population are comparable with those of patients undergoing knee arthroplasty for osteoarthritis of the knee. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Aged↗
PubMed2006

Use of metal-on-metal total hip resurfacing for the treatment of osteonecrosis of the femoral head.

BACKGROUND: Recently, with the advent of improved metal-on-metal prostheses, total hip resurfacing has emerged as a viable arthroplasty option. However, it remains controversial whether this procedure should be used in patients with osteonecrosis when the femoral resurfacing component is cemented onto dead bone. The purpose of this study was to analyze the clinical and radiographic outcomes of metal-on-metal total hip resurfacing arthroplasty in patients with osteonecrosis of the femoral head. In addition, this group was compared with a matched group of patients who were diagnosed as having osteoarthritis. METHODS: Forty-two osteonecrotic hips that were treated with a metal-on-metal total hip resurfacing arthroplasty were studied. They were matched by gender, age, prosthesis, surgeon, and surgical approach to forty-two osteoarthritic hips that were treated with the same metal-on-metal prosthesis. In the osteonecrosis group, there were twenty-five men and eleven women, and in the osteoarthritis group, there were twenty-eight men and thirteen women. The mean age at the time of surgery was forty-two years. Patients were followed both clinically and radiographically for a mean of forty-one months. RESULTS: The clinical outcomes were similar for both groups, with a good or excellent outcome in thirty-nine hips (93%) with osteonecrosis and a good or excellent outcome in forty-one hips (98%) with osteoarthritis. In each of the two groups, there were two failures that required conversion to a standard total hip arthroplasty. Survivorship curves were similar for the two patient groups. CONCLUSIONS: The short-term results for metal-on-metal total hip resurfacing for this challenging patient population with osteonecrosis were excellent and comparable with those seen in patients with osteoarthritis. We await long-term results to see if these early results are maintained. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Adolescent↗
PubMed2006

Use of an alumina-on-alumina bearing system in total hip arthroplasty for osteonecrosis of the hip.

BACKGROUND: The results of total hip arthroplasty in patients with osteonecrosis of the femoral head are not always optimal. The use of alumina-on-alumina interfaces in young and active patients may decrease wear and lower the rate of aseptic loosening of the implant and appears to be an attractive alternative to the use of conventional cobalt-chromium-on-polyethylene bearings. The purpose of this study was to evaluate the safety and efficacy of the alumina-on-alumina bearing in patients with osteonecrosis and to compare this group of patients to a group of similarly treated patients with osteoarthritis and a group of patients who received conventional cobalt-chromium-on-polyethylene bearings. METHODS: Patients were selected from a United States Investigational Device Exemption multicenter prospective randomized clinical study that was initiated in 1996. Seventy patients with osteonecrosis of the femoral head (seventy-nine hips) received a cementless alumina-on-alumina bearing system and were directly matched to seventy-six patients with osteoarthritis of the hip (seventy-nine hips) who were managed with the same implant. Both groups were compared with twenty-five patients (twenty-six hips) with osteonecrosis and twenty-five patients (twenty-six hips) with osteoarthritis who were managed with a cementless cobalt-chromium-on-polyethylene bearing system. All patients received a cementless hydroxyapatite-coated femoral stem and were followed both clinically and radiographically. RESULTS: The clinical outcomes for alumina-on-alumina bearings were similar for both osteonecrotic and osteoarthritic hips. The seven-year survival probability was 95.5% for the osteonecrotic hips and 89.4% for the osteoarthritic hips in the alumina-on-alumina bearing group and 92.3% for the osteonecrotic hips and 92.9% for the osteoarthritic hips in the cobalt-chromium-on-polyethylene bearing group. At the time of the most recent follow-up, the mean Harris hip score was 96 points for both the osteonecrotic and the osteoarthritic hips in the alumina-on-alumina group and 96 points for the osteonecrotic hips and 97 points for the osteoarthritic hips in the cobalt-chromium-on-polyethylene bearing group. CONCLUSIONS: The results of the use of alumina-on-alumina and cobalt-chromium-on-polyethylene bearings in cementless standard total hip implants in patients with osteonecrosis and osteoarthritis were comparable. The low revision rate for the alumina-on-alumina bearing is encouraging and offers a promising option for younger, more active patients who have this challenging disease. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Adult↗
PubMed2006

Sports activity after total hip and knee arthroplasty : specific recommendations concerning tennis.

Lower extremity total joint arthroplasties are among the most successful operations in orthopaedics. Presently, it appears that some patients wish to not only have general functions restored, but also desire the opportunity to return or continue on a high level of activity. This review summarises the literature concerning athletic activity, and tennis in particular, in relation to lower extremity total joint arthroplasties. Orthopaedic surgeons frequently recommend participation in low-impact sports such as swimming, walking, bicycling, bowling and golf. The patient's return to these recreational activities appears to be without problems. In contrast, there has been a general consensus from surgeons to avoid high-impact sports such as tennis and jogging after total joint arthroplasty, but there have been numerous studies that reported functional results being compatible with these activity levels. Conflicts emerge with some studies that describe lower survival rates for hip and knee arthroplasty in patients participating in high-impact sports. Most of these studies report that participation in sporting activities following total joint arthroplasty refers to increased polyethylene wear and debris, which could eventually result in implant failure. With recent advances in implant technology and surgical technique, the survival rates for modern prosthetic designs and patients with these high demands are promising. Various studies assessing the association between clinical outcome and participation in tennis did not demonstrate a harmful effect on implant survival rates. Although the majority of these studies do not reflect a true representation of the average patient undergoing total joint arthroplasty, more surgeons are confronted with the patients' desire to continue with sports activity. To optimise results, patients who demand higher levels of activity must be carefully selected, and must have the motivation and drive to optimise their results. In general, all patients should be encouraged to remain physically active to improve general health, maintain good bone quality, and improve implant fixation. There is still a need for prospective, randomised controlled studies concerning high activity and its impact on total joint arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2006

Hip resurfacing arthroplasty.

Hip resurfacing arthroplasty is a type of hip replacement that involves capping the femoral head and preserving bone of the proximal femur. Metal-on-metal surface replacements have been manufactured since the early 1990s. Recent studies indicate excellent clinical results with low failure rates at 1- to 5-year follow-up. Although these early results are encouraging, resurfacing devices must be used with caution because less is known about their long-term safety and efficacy. The best candidates for resurfacing are patients younger than age 60 years with good bone stock. The surgical approach is similar to that for standard total hip replacements, but with slightly more dissection because the femoral head must be preserved and displaced to visualize the acetabulum. To reduce complications, resurfacing arthroplasty should be performed by surgeons who have received training specifically in this technique.

Arthroplasty, Replacement, Hip↗
PubMed2006

Use of modular large femoral heads without liners in hip arthroplasty.

The use of large-diameter femoral heads in total hip arthroplasty appears to reduce the risk for dislocation, and potentially improve articular wear. Moreover, large-diameter total hip femoral heads have been determined to increase range of motion. The purpose of this study was to report our experiences with this new device. In our patient cohort, many patients have done extremely well in the short-term with this new device, and it seems these patients function better than those with a standard total hip arthroplasty. The patients who experience less pain are able to return to full activities postoperatively. The preliminary results of this study are encouraging, and large femoral head prosthesis appears to be a great choice for orthopaedic surgeons in primary total hip arthroplasty.

Adult↗
PubMed2005

BLyS and APRIL in rheumatoid arthritis.

The cytokines B lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL) enhance autoimmune disease by sustaining B cell activation. In RA, B cells contribute to the formation of 3 functionally distinct types of lymphoid microarchitectures in the inflamed synovium: ectopic GCs; T cell-B cell aggregates lacking GC reactions; and unorganized, diffuse infiltrates. We examined 72 tissues representing the 3 types of synovitis for BLyS and APRIL production and for expression of APRIL/BLyS receptors. Biologic effects of BLyS and APRIL were explored by treating human synovium-SCID mouse chimeras with the APRIL and BLyS decoy receptor transmembrane activator and CAML interactor:Fc (TACI:Fc). GC+ synovitis had the highest levels of APRIL, produced exclusively by CD83+ DCs. BLyS was present in similar levels in all tissue types and derived exclusively from CD68+ macrophages. In GC+ synovitis, treatment with TACI:Fc resulted in GC destruction and marked inhibition of IFN-gamma and Ig transcription. In contrast, inhibition of APRIL and BLyS in aggregate and diffuse synovitis left Ig levels unaffected and enhanced IFN-gamma production. These differential immunomodulatory effects correlated with the presence of TACI+ T cells in aggregate and diffuse synovitis and their absence in GC+ synovitis. We propose that BLyS and APRIL regulate B cell as well as T cell function and have pro- and antiinflammatory activities in RA.

Adult↗
PubMed2005

B cells in rheumatoid synovitis.

In rheumatoid arthritis, T cells, B cells, macrophages, and dendritic cells invade the synovial membranes, establishing complex microstructures that promote inflammatory/tissue destructive lesions. B cell involvement has been considered to be limited to autoantibody production. However, recent studies suggest that B cells support rheumatoid disease through other mechanisms. A critical element of rheumatoid synovitis is the process of ectopic lymphoid neogenesis, with highly efficient lymphoid architectures established in a nonlymphoid tissue site. Rheumatoid synovitis recapitulates the pathways of lymph node formation, and B cells play a key role in this process. Furthermore, studies of rheumatoid lesions implanted in immunodeficient mice suggest that T cell activation in synovitis is B cell dependent, indicating the role played by B cells in presenting antigens and providing survival signals.

Animals↗
PubMed2005

B cells as a therapeutic target in autoimmune diseases.

Historically, the pathogenic role of B cells in autoimmune disease has been attributed to the formation of autoantibodies which, as soluble immunoglobulins or immunocomplexes, can trigger cellular damage and initiate the inflammatory cascade. Recent results from clinical trials applying B cell-directed therapeutics in rheumatoid arthritis and systemic lupus erythematosus have challenged such traditional views and encouraged novel ideas about the disease involvement of B cells. Suppression of disease activity, often disconnected from effects on autoantibody titers, has supported the notion that B cells may promote autoimmune disease by serving as antigen-presenting cells that sustain T cell activation. Likewise, B cells have been implicated in supporting the process of ectopic lymphoid neogenesis, a mechanism that stabilises pathogenic immune responses in target tissues and thus contributes to disease chronicity. As a general rule, clinical effects of B cell-directed therapeutics have often been unanticipated and unpredicted by experimental models, emphasis-ing the need to explore and verify disease principles in the patient.

Autoimmune Diseases↗
PubMed2005

Reductions in blood loss with use of a bipolar sealer for hemostasis in primary total knee arthroplasty.

Fifty primary total knee arthroplasties were performed in a prospective, randomized study comparing the use of a bipolar sealer device versus conventional electrocautery as the method of hemostasis. Both cohorts were evaluated for intraoperative blood loss, transfusion rate, postoperative drainage, hemoglobin levels, and Knee Society scores. A significant reduction in postoperative and total blood loss was found (p = 0.05 and p = 0.02, respectively), as well as an absence of tissue charring and smoke production in the bipolar sealer group. No difference in knee scores was found between both cohorts. These results suggest that use of this bipolar sealing device is at least as effective as standard cautery devices and can reduce blood loss, tissue damage, and smoke production in total knee arthroplasties without affecting the results.

Adult↗