Geert Pagenstert | University of Basel, Switzerland (original) (raw)
Papers by Geert Pagenstert
Journal of orthopaedic research : official publication of the Orthopaedic Research Society, Jan 6, 2015
Subchondral osteosclerosis, characterized by an increase of hypomineralized bone material, is a p... more Subchondral osteosclerosis, characterized by an increase of hypomineralized bone material, is a pathological hallmark of osteoarthritis. The cellular components in the subchondral marrow compartment that participate in this aberrant bone remodeling process remain to be elucidated. This study assessed the presence of marrow inflammatory cells and their relative abundance between nonsclerotic and sclerotic tissues in knee osteoarthritis. Bone samples from osteoarthritic knee tibial plateaus were stratified for histological analyses using computed tomography osteoabsorptiometry. Immunohistological analysis revealed the presence of CD20 (B-lymphocyte) and CD68 (macrophage), but not CD3 (T-lymphocyte) immunoreactive mononuclear cells in subchondral marrow tissues and their relative abundance was significantly increased in sclerotic compared with nonsclerotic bone samples. Multinucleated osteoclasts that stained positive for CD68 and tartrate-resistant acid phosphatase, predominantly asso...
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2010
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2011
... Osteochondroma of the distal Tibia – Case Report. Martin Wiewiorski 1 , André Leumann 1 , Dan... more ... Osteochondroma of the distal Tibia – Case Report. Martin Wiewiorski 1 , André Leumann 1 , Daniel Baumhoer 2 , Geert Pagenstert 1 and Victor Valderrabano 1 , Corresponding Author Contact Information , E-mail The Corresponding Author. ...
Therapeutische Umschau, 2015
Osteoarthrits is listed number one reason for adult disability. Therefore treatment of arthritis ... more Osteoarthrits is listed number one reason for adult disability. Therefore treatment of arthritis has maximum impact for the general practitioner. Disability of knee and ankle osteoarthritis causes inability to work and loss of independence. Patients will ask their physicians about expectations after total knee or ankle arthroplasty when other treatment has failed. The satisfaction rate after knee prosthesis is 75 – 89 % and for total ankle arthroplasty even slightly higher at 79 – 97 %. This is surprising because the survival in joint registry data after knee arthroplasty is 94 % compared to ankle arthroplasty significantly less at 69 % after 10 years, when a component revision is used as endpoint. In addition, knee component revision usually means exchanging to knee revision prosthesis while at the ankle it is usually prosthetic removal and conversion to ankle fusion. This difference of satisfaction is probably caused by the fact that knee arthroplasty is a standard operation and patients have very high expectations. Key to this is realistic patient education before surgery by general practitioners and specialists about the typical postoperative course with significant pain reduction not within days but rather in the first 2 postoperative years with moderate activity allowed. Candidates for total ankle replacement must be carefully selected because the prosthesis relies on a good bone stock, stable ligaments and proper limb alignment. Unlike for the knee, none of these can currently be corrected by the ankle prosthesis itself. Patients can expect significant pain reduction, better function and a slight improved range of motion after knee and ankle prosthesis. Sports activities are possible, but should be in a low-impact area. Heavy physical work or running and jumping activities are usually not possible and surely not recommended due to increased wear.
Techniques in Foot & Ankle Surgery, 2013
ABSTRACT
Clinical orthopaedics and related research, 2013
Foot and ankle clinics, 2006
Precise knowledge of lateral ankle ligaments anatomy and biomechanics is mandatory for successful... more Precise knowledge of lateral ankle ligaments anatomy and biomechanics is mandatory for successful surgical reconstruction. The displayed reconstruction procedure fulfilled these requirements, and showed excellent clinical outcome. The described harvesting of the plantaris tendon at the proximal calf allows the use of a relatively long tendon autograft compared with the traditional harvesting procedure at the os calcis. Consequently, this procedure gives the surgeon a more efficient access to a local tendon autograft for numerous surgical procedures in the field of foot and ankle surgery.
Foot and Ankle Clinics, 2006
The medial ligaments of the ankle are injured more often than generally believed. Complete deltoi... more The medial ligaments of the ankle are injured more often than generally believed. Complete deltoid ligament tears are occasionally seen in association with lateral malleolar fractures or bimalleolar fractures. Chronic deltoid ligament insufficiency can be seen in several conditions, including posterior tibial tendon disorder, trauma- and sports-related deltoid disruptions, and valgus talar tilting in patients who have a history of triple arthrodesis or total ankle arthroplasty. This article focuses on the anatomy and function of the medial ligaments of the ankle and establishes a rationale for the diagnosis and treatment of incompetent deltoid ligament.
Knee Surgery, Sports Traumatology, Arthroscopy, 2013
This study reports first evidence of a modified procedure for osteochondral autologous transplant... more This study reports first evidence of a modified procedure for osteochondral autologous transplantation where bony periosteum-covered plugs are harvested at the iliac crest and transplanted into the talar osteochondral lesion. Thirteen out of 14 patients, average age 39.6 (SD 14.4) years, were followed clinically and radiographically for a median of 25 (24-28) months (minimal follow-up, 24 months). For these 13 patients, the American Orthopaedic Foot and Ankle Society hindfoot score increased from 47 (SD 11) points pre-operatively, to 81 (SD 14) points postoperatively (p < 0.0001). The average pain score decreased from 6.6 (SD 1.3) points pre-operatively, to 1.4 (SD 1.9) points postoperatively (p < 0.0001). Seven patients returned to sports activity. Radiographically good plug osteointegration was observed in nine out of 11 ankles. Follow-up arthroscopy showed fibrous cartilage in four ankles, periosteum hypertrophy in five ankles, and partial or total missing of coverage of the bone in three ankles. Three revision surgeries had to be performed. This modified mosaicplasty might be recommended for severe and recurrent osteochondral lesions of the talus and may lead to restoration of the subchondral bone stock, formation of fibro-cartilage, and stable joint function. IV.
Der Orthopäde
Total ankle replacement is becoming an increasingly used treatment for patients with degenerative... more Total ankle replacement is becoming an increasingly used treatment for patients with degenerative arthritis of the ankle; however, there is limited literature available addressing the incidence of thromboembolic complications after total ankle replacement. Therefore, we performed a systematic literature review addressing thrombosis prophylaxis and incidence of thromboembolic complications after total ankle replacement. Furthermore, we evaluated the incidence of thromboembolic complications in our clinic. A systemic literature review was performed using established medical literature data bases. The following information was retrieved from the literature: thrombosis prophylaxis and duration and deep vein thrombosis/pulmonary embolism as postoperative complication. The incidence of thromboembolic complications was evaluated in our patient cohort including 964 total ankle replacement procedures. A total of 21 clinical studies were included in the systematic literature review. The range of incidence of thromboembolic complications was between 0.0 % and 4.8 %. In our patient cohort the incidence of symptomatic deep vein thrombosis was 3.4 %. There were no cases of pulmonary embolism. All patients received low molecular weight heparin prophylaxis. The incidence of thromboembolic complications in our patient cohort was comparable to that of symptomatic deep vein thrombosis in patients undergoing total knee or hip replacement or ankle fusion. We suggest the prophylactic use of low molecular weight heparin for patients after total ankle replacement.
Sportverletzung · Sportschaden
Chronic ankle instability represents a typical sports injury which can mostly be seen in basketba... more Chronic ankle instability represents a typical sports injury which can mostly be seen in basketball, soccer, orienteering and other high risk sports. 20 to 40 % of the acute ankle sprains develop into chronic ankle instability. From a sports orthopaedic point of view, chronic ankle instability can be subdivided into a lateral, medial or a combination of both so called rotational ankle instability. From a pathophysiological point of view, chronic ankle instability can be either mechanical with a structural ligament lesion or functional with loss of the neuromuscular control. For the sports physician, the chronic ankle instability is a difficult entity as the diagnosis is usually complex and the therapy usually surgical. This review on chronic ankle instability addresses pathomechanism, diagnostics, indications for conservative and surgical treatments, and possible long-term sequelae, as ligamentous osteoarthritis.
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2009
ABSTRACT Introduction Magnet resonance imaging (MRI) is the gold-standard of non-invasive diagnos... more ABSTRACT Introduction Magnet resonance imaging (MRI) is the gold-standard of non-invasive diagnostics in OCL of the talus. Single photon emission computed tomography – computed tomography (SPECT-CT) shows additional, high-resolutioned information of osteoblastic (szintigraphic) activity and bony morphology. The study aimed for evaluating the influence of the SPECT-CT on clinical application of the imaging information and decision-making in OCL therapy. Methods MRI and SPECT-CT of 26 patients (average age: 32 y) were analyzed separately by 3 blinded, independent orthopaedic foot and ankle surgeons experienced in treating OCL and working with MRI and SPECT-CT for treatment decision-making. Imaging information was analyzed by using a specified questionnaire. Results By the SPECT-CT, a change in treatment was documented in 46 of 78 decisions (59%) in comparison to the MRI. Following treatment decisions were chosen most often (total decisions: 156): Retrograde drilling: 64 (41.0%); microfracture and antegrade drilling: 28 (17.9%); osteochondral autologous transplantation (mosaicplasty): 23 (14.8%); excision and debridement: 16 (10.3%); physiotherapy: 9 (5.8%); autologous chondrocyte implantation: 5 (3.2%); joint-sacrificing therapy (e.g. joint replacement): 5 (3.2%); cancellous bone grafting: 4 (2.6%); passive conservative therapy (e.g. cast): 1 (0.6%); drug therapy (e.g. hyaluronic acid): 1 (0.6%); refixation: 0 (0%). However, overall distribution of therapies remained unchanged between MRI and SPECT-CT. The questionnaire revealed main differences in imaging interpretation for: subchondral bone plate morphology (17; 65%), subchondral sclerosis (16; 62%), subchondral cysts (11; 42%), and kissing lesions (10; 38%). The area of szintigraphic activity in comparison to bone bruise was found to be smaller in 50% of cases (13) and bigger in 27% (7 cases). Discussion The additional information provided by the SPECT-CT influences the decision-making for the treatment of OCL in the talus significantly. This is due to changed interpretation of subchondral bone plate morphology and subchondral bone activity. No study reported on SPECT-CT in OCL yet. SPECT-CT may become important in diagnostics and treatment decision-making in OCL of the talus.
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Joint preserving surgeries have gained popularity as treatment of asymmetric early ... more Introduction: Joint preserving surgeries have gained popularity as treatment of asymmetric early and mid-stage ankle osteoarthritis. However, only limited long-term data on strength and walking biomechanics are available. Therefore, the purpose of this study was to quantify isometric plantar- and dorsiflexion strength and gait parameters (dynamic range of motion, peak moments) in patients who underwent realignment surgery. Methods: Eight patients, a minimum of seven years after realignment surgery (age: 44.7 ± 7.0 years); body mass index (BMI): 27.2 ± 4.6), and eight age-and gender matched healthy controls (age: 44.3 ± 6.6 years; BMI: 25.2 ± 3.4 kg/m2) were included in the study. The measurements consisted of 1) an instrumented gait analysis with a six camera motion analysis system (Vicon, Oxford, UK) and two force plates (Kistler, Winterthur, Switzerland) to assess ankle, knee, and hip kinematics and kinetics, and 2) an isometric torque measurement (torque transducer: SM-500N, Inte...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Osteoarthritis (OA) of the ankle is often asymmetric with a hindfoot malalignment i... more Introduction: Osteoarthritis (OA) of the ankle is often asymmetric with a hindfoot malalignment into varus or valgus. Patients often have partially intact articular cartilage and can benefit from joint preserving realignment surgery with hindfoot and supramalleolar osteotomies. The purpose of this study was to quantify bilateral biomechanical and neuromuscular adaptations during walking in patients with asymmetric ankle OA before and after realignment surgery. Methods: A 3D gait analysis with bilateral surface electromyography (EMG) of gastrocnemius medialis, soleus, peroneus longus, and tibialis anterior was performed in: 7 patients with asymmetric ankle OA before (P1a) and 12 to 18 months after surgery (P1b), 7 other patients 8 to 9 years after surgery (P2), and 15 healthy subjects (C). For each subject 6 trials were recorded. EMG envelopes of each muscle were analyzed using principal component analysis (input: 101 time points x 432 trials). The first 2 principal components (PC) s...
Foot & ankle international, Jan 31, 2015
We analyzed the histopathologic findings in end-stage osteoarthritic ankle joint tissue that disp... more We analyzed the histopathologic findings in end-stage osteoarthritic ankle joint tissue that display increased uptake of bone-seeking radiotracer in single-photon emission computed tomography-computed tomography (SPECT-CT) imaging. Six consecutive patients with end-stage osteoarthritis undergoing total ankle replacement received preoperative SPECT-CT imaging using (99m)Technetium dicarboxypropane diphosphonate ((99m)Tc-DPD). Using imaging data for stratification, osteochondral tissue sections were prepared from SPECT-positive (+) and -negative (-) areas of tibial and talar resection specimens. Histomorphometric analyses of osteoblast numbers, collagen deposition, and cartilage degeneration were performed on hematoxylin and eosin, van Gieson's and Safranin-O stained tissue sections. Osteoclast activity was visualized using tartrate-resistant acid phosphatase (TRAP) staining. Increased (99m)Tc-DPD uptake was observed exclusively subjacent to the subchondral bone plate of tibial an...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Objective: Single photon emission computed tomography (SPECT)-CT is an emerging diagnostic imagin... more Objective: Single photon emission computed tomography (SPECT)-CT is an emerging diagnostic imaging tool for osteoarthritis (OA). While subchondral bone sclerosis is a hallmark of end-stage OA, the cellular and molecular mechanisms of increased bone turnover in OA remain elusive. In this study, we investigated the cellular mechanisms of increased bone remodeling, defined by SPECT-CT, in patients suffering from end-stage ankle OA. Methods: Pre-operative SPECT-CT imaging, using 99mTechnetiumdicarboxypropane diphosphanate (99mTc-DPD), was performed in six consecutive OA patients (mean age 63, range 52–72) undergoing total ankle replacement. AOFAS score and VAS were used for clinical evaluation in this study group. Intra-operative distal tibial and talar resections were obtained and standardized samples (5 x 5 mm) were divided into four categories according to subchondral bone density (low or high) and 99mTc-DPD uptake (negative or positive). For histological analyses, tissue sections (1...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Single photon emission computed tomography (SPECT)/CT enables accurate non-invasive... more Introduction: Single photon emission computed tomography (SPECT)/CT enables accurate non-invasive and simultaneous acquisition of information on tissue morphology and biological processes in disease. SPECT/CT imaging using a radiographic bone tracer, such as 99mTechnetium-dicarboxypropane diphosphanate (99mTc-DPD), is frequently applied for differential diagnosis of foot and ankle pathologies that pose a diagnostic challenge due to their complex anatomy. Uptake of bone-seeking radiotracers is primarily determined by the degree of bone perfusion and chemisorption to the hydroxyapatite structure of bone tissue and can be influenced by environmental factors, such as pH. In this study we sought to identify the cellular and morphological changes that associate with increased 99mTc-DPD uptake in ankle joint osteoarthritis (OA). Methods: Six consecutive patients with end-stage ankle OA scheduled for total ankle replacement received preoperative 99mTechnetium-dicarboxypropane-diphosphanate ...
Journal of orthopaedic research : official publication of the Orthopaedic Research Society, Jan 6, 2015
Subchondral osteosclerosis, characterized by an increase of hypomineralized bone material, is a p... more Subchondral osteosclerosis, characterized by an increase of hypomineralized bone material, is a pathological hallmark of osteoarthritis. The cellular components in the subchondral marrow compartment that participate in this aberrant bone remodeling process remain to be elucidated. This study assessed the presence of marrow inflammatory cells and their relative abundance between nonsclerotic and sclerotic tissues in knee osteoarthritis. Bone samples from osteoarthritic knee tibial plateaus were stratified for histological analyses using computed tomography osteoabsorptiometry. Immunohistological analysis revealed the presence of CD20 (B-lymphocyte) and CD68 (macrophage), but not CD3 (T-lymphocyte) immunoreactive mononuclear cells in subchondral marrow tissues and their relative abundance was significantly increased in sclerotic compared with nonsclerotic bone samples. Multinucleated osteoclasts that stained positive for CD68 and tartrate-resistant acid phosphatase, predominantly asso...
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2010
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2011
... Osteochondroma of the distal Tibia – Case Report. Martin Wiewiorski 1 , André Leumann 1 , Dan... more ... Osteochondroma of the distal Tibia – Case Report. Martin Wiewiorski 1 , André Leumann 1 , Daniel Baumhoer 2 , Geert Pagenstert 1 and Victor Valderrabano 1 , Corresponding Author Contact Information , E-mail The Corresponding Author. ...
Therapeutische Umschau, 2015
Osteoarthrits is listed number one reason for adult disability. Therefore treatment of arthritis ... more Osteoarthrits is listed number one reason for adult disability. Therefore treatment of arthritis has maximum impact for the general practitioner. Disability of knee and ankle osteoarthritis causes inability to work and loss of independence. Patients will ask their physicians about expectations after total knee or ankle arthroplasty when other treatment has failed. The satisfaction rate after knee prosthesis is 75 – 89 % and for total ankle arthroplasty even slightly higher at 79 – 97 %. This is surprising because the survival in joint registry data after knee arthroplasty is 94 % compared to ankle arthroplasty significantly less at 69 % after 10 years, when a component revision is used as endpoint. In addition, knee component revision usually means exchanging to knee revision prosthesis while at the ankle it is usually prosthetic removal and conversion to ankle fusion. This difference of satisfaction is probably caused by the fact that knee arthroplasty is a standard operation and patients have very high expectations. Key to this is realistic patient education before surgery by general practitioners and specialists about the typical postoperative course with significant pain reduction not within days but rather in the first 2 postoperative years with moderate activity allowed. Candidates for total ankle replacement must be carefully selected because the prosthesis relies on a good bone stock, stable ligaments and proper limb alignment. Unlike for the knee, none of these can currently be corrected by the ankle prosthesis itself. Patients can expect significant pain reduction, better function and a slight improved range of motion after knee and ankle prosthesis. Sports activities are possible, but should be in a low-impact area. Heavy physical work or running and jumping activities are usually not possible and surely not recommended due to increased wear.
Techniques in Foot & Ankle Surgery, 2013
ABSTRACT
Clinical orthopaedics and related research, 2013
Foot and ankle clinics, 2006
Precise knowledge of lateral ankle ligaments anatomy and biomechanics is mandatory for successful... more Precise knowledge of lateral ankle ligaments anatomy and biomechanics is mandatory for successful surgical reconstruction. The displayed reconstruction procedure fulfilled these requirements, and showed excellent clinical outcome. The described harvesting of the plantaris tendon at the proximal calf allows the use of a relatively long tendon autograft compared with the traditional harvesting procedure at the os calcis. Consequently, this procedure gives the surgeon a more efficient access to a local tendon autograft for numerous surgical procedures in the field of foot and ankle surgery.
Foot and Ankle Clinics, 2006
The medial ligaments of the ankle are injured more often than generally believed. Complete deltoi... more The medial ligaments of the ankle are injured more often than generally believed. Complete deltoid ligament tears are occasionally seen in association with lateral malleolar fractures or bimalleolar fractures. Chronic deltoid ligament insufficiency can be seen in several conditions, including posterior tibial tendon disorder, trauma- and sports-related deltoid disruptions, and valgus talar tilting in patients who have a history of triple arthrodesis or total ankle arthroplasty. This article focuses on the anatomy and function of the medial ligaments of the ankle and establishes a rationale for the diagnosis and treatment of incompetent deltoid ligament.
Knee Surgery, Sports Traumatology, Arthroscopy, 2013
This study reports first evidence of a modified procedure for osteochondral autologous transplant... more This study reports first evidence of a modified procedure for osteochondral autologous transplantation where bony periosteum-covered plugs are harvested at the iliac crest and transplanted into the talar osteochondral lesion. Thirteen out of 14 patients, average age 39.6 (SD 14.4) years, were followed clinically and radiographically for a median of 25 (24-28) months (minimal follow-up, 24 months). For these 13 patients, the American Orthopaedic Foot and Ankle Society hindfoot score increased from 47 (SD 11) points pre-operatively, to 81 (SD 14) points postoperatively (p < 0.0001). The average pain score decreased from 6.6 (SD 1.3) points pre-operatively, to 1.4 (SD 1.9) points postoperatively (p < 0.0001). Seven patients returned to sports activity. Radiographically good plug osteointegration was observed in nine out of 11 ankles. Follow-up arthroscopy showed fibrous cartilage in four ankles, periosteum hypertrophy in five ankles, and partial or total missing of coverage of the bone in three ankles. Three revision surgeries had to be performed. This modified mosaicplasty might be recommended for severe and recurrent osteochondral lesions of the talus and may lead to restoration of the subchondral bone stock, formation of fibro-cartilage, and stable joint function. IV.
Der Orthopäde
Total ankle replacement is becoming an increasingly used treatment for patients with degenerative... more Total ankle replacement is becoming an increasingly used treatment for patients with degenerative arthritis of the ankle; however, there is limited literature available addressing the incidence of thromboembolic complications after total ankle replacement. Therefore, we performed a systematic literature review addressing thrombosis prophylaxis and incidence of thromboembolic complications after total ankle replacement. Furthermore, we evaluated the incidence of thromboembolic complications in our clinic. A systemic literature review was performed using established medical literature data bases. The following information was retrieved from the literature: thrombosis prophylaxis and duration and deep vein thrombosis/pulmonary embolism as postoperative complication. The incidence of thromboembolic complications was evaluated in our patient cohort including 964 total ankle replacement procedures. A total of 21 clinical studies were included in the systematic literature review. The range of incidence of thromboembolic complications was between 0.0 % and 4.8 %. In our patient cohort the incidence of symptomatic deep vein thrombosis was 3.4 %. There were no cases of pulmonary embolism. All patients received low molecular weight heparin prophylaxis. The incidence of thromboembolic complications in our patient cohort was comparable to that of symptomatic deep vein thrombosis in patients undergoing total knee or hip replacement or ankle fusion. We suggest the prophylactic use of low molecular weight heparin for patients after total ankle replacement.
Sportverletzung · Sportschaden
Chronic ankle instability represents a typical sports injury which can mostly be seen in basketba... more Chronic ankle instability represents a typical sports injury which can mostly be seen in basketball, soccer, orienteering and other high risk sports. 20 to 40 % of the acute ankle sprains develop into chronic ankle instability. From a sports orthopaedic point of view, chronic ankle instability can be subdivided into a lateral, medial or a combination of both so called rotational ankle instability. From a pathophysiological point of view, chronic ankle instability can be either mechanical with a structural ligament lesion or functional with loss of the neuromuscular control. For the sports physician, the chronic ankle instability is a difficult entity as the diagnosis is usually complex and the therapy usually surgical. This review on chronic ankle instability addresses pathomechanism, diagnostics, indications for conservative and surgical treatments, and possible long-term sequelae, as ligamentous osteoarthritis.
Sport-Orthopädie - Sport-Traumatologie - Sports Orthopaedics and Traumatology, 2009
ABSTRACT Introduction Magnet resonance imaging (MRI) is the gold-standard of non-invasive diagnos... more ABSTRACT Introduction Magnet resonance imaging (MRI) is the gold-standard of non-invasive diagnostics in OCL of the talus. Single photon emission computed tomography – computed tomography (SPECT-CT) shows additional, high-resolutioned information of osteoblastic (szintigraphic) activity and bony morphology. The study aimed for evaluating the influence of the SPECT-CT on clinical application of the imaging information and decision-making in OCL therapy. Methods MRI and SPECT-CT of 26 patients (average age: 32 y) were analyzed separately by 3 blinded, independent orthopaedic foot and ankle surgeons experienced in treating OCL and working with MRI and SPECT-CT for treatment decision-making. Imaging information was analyzed by using a specified questionnaire. Results By the SPECT-CT, a change in treatment was documented in 46 of 78 decisions (59%) in comparison to the MRI. Following treatment decisions were chosen most often (total decisions: 156): Retrograde drilling: 64 (41.0%); microfracture and antegrade drilling: 28 (17.9%); osteochondral autologous transplantation (mosaicplasty): 23 (14.8%); excision and debridement: 16 (10.3%); physiotherapy: 9 (5.8%); autologous chondrocyte implantation: 5 (3.2%); joint-sacrificing therapy (e.g. joint replacement): 5 (3.2%); cancellous bone grafting: 4 (2.6%); passive conservative therapy (e.g. cast): 1 (0.6%); drug therapy (e.g. hyaluronic acid): 1 (0.6%); refixation: 0 (0%). However, overall distribution of therapies remained unchanged between MRI and SPECT-CT. The questionnaire revealed main differences in imaging interpretation for: subchondral bone plate morphology (17; 65%), subchondral sclerosis (16; 62%), subchondral cysts (11; 42%), and kissing lesions (10; 38%). The area of szintigraphic activity in comparison to bone bruise was found to be smaller in 50% of cases (13) and bigger in 27% (7 cases). Discussion The additional information provided by the SPECT-CT influences the decision-making for the treatment of OCL in the talus significantly. This is due to changed interpretation of subchondral bone plate morphology and subchondral bone activity. No study reported on SPECT-CT in OCL yet. SPECT-CT may become important in diagnostics and treatment decision-making in OCL of the talus.
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Joint preserving surgeries have gained popularity as treatment of asymmetric early ... more Introduction: Joint preserving surgeries have gained popularity as treatment of asymmetric early and mid-stage ankle osteoarthritis. However, only limited long-term data on strength and walking biomechanics are available. Therefore, the purpose of this study was to quantify isometric plantar- and dorsiflexion strength and gait parameters (dynamic range of motion, peak moments) in patients who underwent realignment surgery. Methods: Eight patients, a minimum of seven years after realignment surgery (age: 44.7 ± 7.0 years); body mass index (BMI): 27.2 ± 4.6), and eight age-and gender matched healthy controls (age: 44.3 ± 6.6 years; BMI: 25.2 ± 3.4 kg/m2) were included in the study. The measurements consisted of 1) an instrumented gait analysis with a six camera motion analysis system (Vicon, Oxford, UK) and two force plates (Kistler, Winterthur, Switzerland) to assess ankle, knee, and hip kinematics and kinetics, and 2) an isometric torque measurement (torque transducer: SM-500N, Inte...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Osteoarthritis (OA) of the ankle is often asymmetric with a hindfoot malalignment i... more Introduction: Osteoarthritis (OA) of the ankle is often asymmetric with a hindfoot malalignment into varus or valgus. Patients often have partially intact articular cartilage and can benefit from joint preserving realignment surgery with hindfoot and supramalleolar osteotomies. The purpose of this study was to quantify bilateral biomechanical and neuromuscular adaptations during walking in patients with asymmetric ankle OA before and after realignment surgery. Methods: A 3D gait analysis with bilateral surface electromyography (EMG) of gastrocnemius medialis, soleus, peroneus longus, and tibialis anterior was performed in: 7 patients with asymmetric ankle OA before (P1a) and 12 to 18 months after surgery (P1b), 7 other patients 8 to 9 years after surgery (P2), and 15 healthy subjects (C). For each subject 6 trials were recorded. EMG envelopes of each muscle were analyzed using principal component analysis (input: 101 time points x 432 trials). The first 2 principal components (PC) s...
Foot & ankle international, Jan 31, 2015
We analyzed the histopathologic findings in end-stage osteoarthritic ankle joint tissue that disp... more We analyzed the histopathologic findings in end-stage osteoarthritic ankle joint tissue that display increased uptake of bone-seeking radiotracer in single-photon emission computed tomography-computed tomography (SPECT-CT) imaging. Six consecutive patients with end-stage osteoarthritis undergoing total ankle replacement received preoperative SPECT-CT imaging using (99m)Technetium dicarboxypropane diphosphonate ((99m)Tc-DPD). Using imaging data for stratification, osteochondral tissue sections were prepared from SPECT-positive (+) and -negative (-) areas of tibial and talar resection specimens. Histomorphometric analyses of osteoblast numbers, collagen deposition, and cartilage degeneration were performed on hematoxylin and eosin, van Gieson's and Safranin-O stained tissue sections. Osteoclast activity was visualized using tartrate-resistant acid phosphatase (TRAP) staining. Increased (99m)Tc-DPD uptake was observed exclusively subjacent to the subchondral bone plate of tibial an...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Objective: Single photon emission computed tomography (SPECT)-CT is an emerging diagnostic imagin... more Objective: Single photon emission computed tomography (SPECT)-CT is an emerging diagnostic imaging tool for osteoarthritis (OA). While subchondral bone sclerosis is a hallmark of end-stage OA, the cellular and molecular mechanisms of increased bone turnover in OA remain elusive. In this study, we investigated the cellular mechanisms of increased bone remodeling, defined by SPECT-CT, in patients suffering from end-stage ankle OA. Methods: Pre-operative SPECT-CT imaging, using 99mTechnetiumdicarboxypropane diphosphanate (99mTc-DPD), was performed in six consecutive OA patients (mean age 63, range 52–72) undergoing total ankle replacement. AOFAS score and VAS were used for clinical evaluation in this study group. Intra-operative distal tibial and talar resections were obtained and standardized samples (5 x 5 mm) were divided into four categories according to subchondral bone density (low or high) and 99mTc-DPD uptake (negative or positive). For histological analyses, tissue sections (1...
Swiss medical weekly: official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology
Introduction: Single photon emission computed tomography (SPECT)/CT enables accurate non-invasive... more Introduction: Single photon emission computed tomography (SPECT)/CT enables accurate non-invasive and simultaneous acquisition of information on tissue morphology and biological processes in disease. SPECT/CT imaging using a radiographic bone tracer, such as 99mTechnetium-dicarboxypropane diphosphanate (99mTc-DPD), is frequently applied for differential diagnosis of foot and ankle pathologies that pose a diagnostic challenge due to their complex anatomy. Uptake of bone-seeking radiotracers is primarily determined by the degree of bone perfusion and chemisorption to the hydroxyapatite structure of bone tissue and can be influenced by environmental factors, such as pH. In this study we sought to identify the cellular and morphological changes that associate with increased 99mTc-DPD uptake in ankle joint osteoarthritis (OA). Methods: Six consecutive patients with end-stage ankle OA scheduled for total ankle replacement received preoperative 99mTechnetium-dicarboxypropane-diphosphanate ...