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Ake Carlsson

Publications and source records attributed to Ake Carlsson.

14 recordsLinked to original sources
PubMed2006

Cross-linked N-telopeptide of type I collagen (NTx) in urine as a predictor of periprosthetic osteolysis.

Periprosthetic osteolysis is often nonsymptomatic and hard to visualize by conventional radiography. Cross-linked N-telopeptide of type I collagen (NTx), a marker of osteoclast mediated bone resorption, has been suggested to evaluate local particulate-induced osteolysis in patients operated on with a total hip prosthesis. Urine specimens were sampled after hip joint replacement in 160 patients. NTx was analyzed by a commercially available ELISA kit. Osteolysis was identified in the acetabulum and confirmed at operation. Using analysis of covariance to correct for differences in age, gender, and time after operation, NTx (mean SD) was 36+/-12 BCE/nM creatinine in patients with osteolysis (n=33) and 27+/-13 BCE/nM creatinine in patients without osteolysis (n=127) (p=0.003). Eighteen hips of 38 (47%), demonstrating an annual wear of more than 0.2 mm and an NTx value above 29 BCE/nM creatinine, had been revised due to osteolysis. The osteolysis prevalence in this group was increased 10 times (CI 4-23, p<0.05). Indeed, NTx release and annual wear were both associated with increased prevalence of osteolysis, however, independently of each other. NTx seems a feasible marker of periprosthetic osteolysis. A preoperative baseline NTx level is likely needed for its use as a predictor of periprosthetic osteolysis in individual cases.

Adult↗
PubMed2006

Weight bearing radiographs are not necessary for measurement of polyethylene penetration in total hip prostheses: a radiostereometric study of 111 patients examined in weight-bearing and supine position.

BACKGROUND: Controversy exists as to whether polyethylene (PE) penetration of hip prostheses is underestimated when the measurements are made on radiographs obtained in supine position as compared to weight-bearing position. PATIENTS AND METHODS: We examined 111 patients by radiostereometric analysis (RSA) in the supine and weight-bearing positions. RESULTS: The mean 3-D penetration was 0.68 mm (SD 0.58, range 0.04-3.05) for the supine position and 0.70 mm (SD 0.57, range 0.08-3.01) for the weight-bearing position. The correlation between supine and weight-bearing examinations was 0.99 (p < 0.001). The degree of penetration made no difference. There was no statistically significant difference as to whether the first examination was performed early, i.e. after 3 months, or after 12 months (p = 0.7). INTERPRETATION: The small systematic difference in penetration values between the supine and the weight-bearing positions is of no clinical or methodological importance.

Arthroplasty, Replacement, Hip↗
PubMed2005

Radiostereometric analysis of the double-coated STAR total ankle prosthesis: a 3-5 year follow-up of 5 cases with rheumatoid arthritis and 5 cases with osteoarthrosis.

BACKGROUND: The designs of total ankle prostheses have changed in recent years in order to give better performance. Only a few studies of these ankle prostheses have been published, however, and none on micromotion. PATIENTS AND METHODS: We evaluated 5 patients with rheumatoid arthritis and 5 with osteoarthrosis, 4 (3-5) years after arthroplasty with the double-coated STAR prosthesis. Clinical examination included AOFAS hindfoot score. Standardized a-p and lateral radiographs were taken and RSA analyses were done at regular intervals. RESULTS: There was no difference in results between ankles operated on due to rheumatoid arthritis and due to osteoarthrosis. A rapid initial migration was observed for the tibial components at 6 weeks, but thereafter all but 1 implant seemed stable. The migration pattern for the talar component was similar. Rotation around the 3 axes was observed for the tibial components at 6 weeks, but not thereafter. The talar components became stable for rotation around the longitudinal and sagittal axes, but not around the transverse axis. 8 out of 10 ankles were painless. The median total AOFAS score was 83 and the median range of motion was 32 degrees. None of the 20 components had changed position and there were no signs of bone resorption. INTERPRETATION: Provided the indication is adequate and the prosthesis has been implanted correctly, the double-coated STAR ankle prosthesis will have a satisfactory fixation to underlying bone.

Ankle Joint↗
PubMed2005

Tibio-talocalcaneal arthrodesis as a primary procedure using a retrograde intramedullary nail: a retrospective study of 26 patients with rheumatoid arthritis.

BACKGROUND: Arthrodesis of the ankle joint using screws or external fixation is often a demanding procedure, notably in patients with rheumatoid arthritis. We investigated whether tibio-talocalcaneal arthrodesis with the use of an intramedullary nail is a safe and simple procedure. PATIENTS AND METHODS: We retrospectively reviewed 25 ankles (25 patients) at median 3 (1-7) years after tibio-talocalcaneal arthrodesis because of rheumatoid arthritis. All had been operated on by retrograde insertion of a retrograde nail. 5 types of nail had been used. Complications, functional outcome scores, and patient satisfaction were determined and the radiographs evaluated for healing. RESULTS: All but 1 ankle had a radiographically healed arthrodesis. We recorded 3 deep infections, all healed--in 2 cases after extraction of the nail--and the arthrodesis healed in all 3 patients. The average functional scores at follow-up were high, considering that the patients suffered from rheumatoid arthritis. 23 patients were satisfied with the outcome. We found a correlation between the functional scores and the general activity of the disease expressed as a Health Assessment Questionnaire score. INTERPRETATION: In patients with rheumatoid arthritis, tibio-talocalcaneal arthrodesis with a retrograde intra-medullary nail results in a high rate of healing, a high rate of patient satisfaction, and relatively few complications.

Adult↗
PubMed2005

Ankle arthrodesis by compression screws in rheumatoid arthritis: primary nonunion in 9/35 patients.

INTRODUCTION: Today, percutaneous or open arthrodesis of the ankle, using one or several screws for fixation, is a common method for treatment of the rheumatic ankle. However, there is very little information in the literature on the reliability of the method. METHODS: We performed a retrospective radiographic and clinical study on 35 ankles of 35 patients. Function was evaluated using the Mazur and AOFAS scores. For evaluation of activity of the rheumatic disease, we used the HAQ score. RESULTS: 31 ankles had healed--26 at the first attempt and 5 after repeat arthrodesis. There was no difference between 13 cases operated on percutaneously and 22 cases operated on with open technique with respect to radiographic healing. Mean AOFAS total score was 56 of possible 86 points. The AOFAS total score correlated with the severity of the rheumatic disease. 20 patients were satisfied with the result, 12 were somewhat satisfied and 3 patients were dissatisfied although the ankle in 2 of these 3 patients had fused. INTERPRETATION: The use of compression screws for fusion of the rheumatic ankle does not appear to give acceptable results regarding healing and function.

Adult↗
PubMed2005

Cemented tibial component fixation performs better than cementless fixation: a randomized radiostereometric study comparing porous-coated, hydroxyapatite-coated and cemented tibial components over 5 years.

BACKGROUND: The question whether the tibial component of a total knee arthroplasty should be fixed to bone with or without bone cement has not yet been definitely answered. We studied movements between the tibial component and bone by radiostereometry (RSA) in total knee replacement (TKR) for 3 different types of fixation: cemented fixation (C-F), uncemented porous fixation (UC-F) and uncemented porous hydroxyapatite fixation (UCHA-F). PATIENTS: 116 patients with osteoarthrosis, who had 146 TKRs, were included in 2 randomized series. The first series included 86 unilateral TKRs stratified into 1 of the 3 types of fixation. The second series included 30 patients who had simultaneous bilateral TKR surgery, and who were stratified into 3 subgroups of pairwise comparisons of the 3 types of fixation. RESULTS: After 5 years 2 knees had been revised, neither of which were due to loosening. 1 UCHA-F knee in the unilateral series showed a large and continuous migration and a poor clinical result, and is a pending failure. The C-F knees rotated and migrated less than UC-F and UCHA-F knees over 5 years. UCHA-F migrated less than UC-F after 1 year. INTERPRETATION: Cementing of the tibial component offers more stable bone-implant contact for 5 years compared to uncemented fixation. When using uncemented components, however, there is evidence that augmenting a porous surface with hydroxyapatite may mean less motion between implant and bone after the initial postoperative year.

Aged↗
PubMed2004

Catastrophic failure of an uncemented acetabular component due to high wear and osteolysis: an analysis of 154 omnifit prostheses with mean 6-year follow-up.

BACKGROUND: The purposes of this study were (1) to evaluate the wear pattern of the hydroxyapatite-coated "Dual Radius" Omnifit cup, (2) to investigate whether wear is correlated to any demographic or prosthesis-related factors, and (3) to describe micromotion of both the cup and the stem. PATIENTS AND METHODS: 154 hips were implanted between 1990 and 1996 and followed for an average of 6 years. Wear was measured according to the "Charnley-duo" method and, in 79 hips, with radiostereometry IRSA). RSA was also used to evaluate micromotion. We analyzed the femoral heads using scanning electron microscopy, energy dispersive X-ray spectroscopy and an atomic force microscope. RESULT: 66 cups were revised and had a mean annual wear of 0.32 mm compared to 0.12 mm in hips not revised. Osteolytic processes were observed in 35 hips but at revision osteolysis was present in 51 cases. 43/66 sockets were loose. Micromotion evaluated by RSA, weight, age, side, size of cup, screws, polyethylene thickness or shelf-life of the polyethylene did not correlate to wear, whereas male gender did. INTERPRETATION: It is still unclear why about half of our cases had an abnormal wear rate. Annual wear exceeding 0.2 mm is prognostic of late failure and should be considered a warning sign.

Acetabulum↗
PubMed2004

Uncemented STAR total ankle prostheses.

BACKGROUND: The feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR). METHODS: Between 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant. RESULTS: Twelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032). CONCLUSIONS: Total ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement.

Ankle Joint↗
PubMed2003

Bone morphology in relation to the migration of porous-coated anatomic knee arthroplasties : a roentgen stereophotogrammetric and histomorphometric study in 23 knees.

The quality of the subchondral bone in total knee arthroplasty (TKA) may be important for the outcome. We correlated a histomorphologic analysis of the prosthetic bone bed to micromotion as analyzed by roentgen stereophotogrammetric analysis (RSA). Twenty-three knees, both osteo- and rheumatoid arthritic were studied. The mean migration after 1 year was 1 mm (0.21-2.68), with no correlation to the bone variables or diagnosis. One patient underwent revision after 3 years because of pain. One patient underwent revision after 15 years because of aseptic loosening. This patient appeared stable according to changes in maximum total point motion (MTPM), but the prosthesis migrated continuously according to segment motion. Prosthetic migration increased after 10 years, zones started to evolve, and the patient became symptomatic after 13 years. A biopsy of the bone bed was taken in all patients. A larger percentage of trabecular bone and a larger relative area of unmineralized osteoid surface were found in patients with rheumatoid arthritis compared with those with osteoarthritis. The latter finding is probably a result of increased bone turnover. In conclusion, no support currently exists for the idea that preoperative bone quality, evaluated as bone histomorphometry, has any impact on prosthetic micromotion in knee prostheses.

Adult↗
PubMed2003

Costs of internal fixation and arthroplasty for displaced femoral neck fractures: a randomized study of 68 patients.

We included in a prospective, randomized study 68 patients aged 70 years or older, with displaced cervical hip fractures. The patients were randomized to internal fixation with hook-pins (36) or primary arthroplasty (32) (total or hemiarthroplasty due to their prefracture status) and followed for 2 years. Patients with rheumatoid arthritis, mental confusion and/or residence in an institution were excluded. The postoperative stay in hospital, rehabilitation wards or nursing homes were recorded as well as complications and the costs of surgery. The aim of this study was to compare the accumulated costs of each method, during the first 2 years after the fracture. In the internal fixation group, 15/36 were considered failures, as compared to 1/32 in the arthroplasty group. As regards primary treatment of the fracture, the durations of surgery and hospital stay were shorter after internal fixation, but the total need for hospitalization/institutionalization was somewhat longer in these patients. The mean 2-year cost for a patient with internal fixation was USD 21,000 and of one with primary arthroplasty USD 15,000. We conclude that primary arthroplasty is a cost-efficient treatment. Considering the very much higher failure rate after internal fixation--leading to increased suffering for these patients--primary arthroplasty stands out as the best method for displaced fractures of the femoral neck.

Aged↗
PubMed2003

Untreated congenital and posttraumatic high dislocation of the hip treated by replacement in adult age: 22 hips in 16 patients followed for 1-8 years.

Between 1993 and 2001, we replaced 22 hips in 16 patients with high dislocation of the hip. All but 1 case was due to congenital dislocation. In all cases the femur was osteotomized below the lesser trochanter and a straight uncemented stem inserted in the medullary canal. The acetabular prostheses were inserted at the site of the original acetabulum, usually after augmenting the acetabular rim by using the medial half of the resected proximal femur. The lateral part of the proximal femur with the intact attachment of the gluteus medius muscle was transposed and fixed to the femoral diaphysis thereby restoring direction of muscle pull. The HHS score increased from a median value of 42 points preoperatively to a median of 86 points after median 25 months of follow-up. Limp, which before surgery was severe in all cases, was less marked or had disappeared at follow-up. The legs had been lengthened median 2.5 (1.0-4.5) cm. No postoperative infections occurred. Palsy or loss of sensory function was not observed in any patient. Dislocation was the commonest complication. It occurred in 3 hips, 2 of which had to be revised to ensure stability.

Adult↗
PubMed2003

Uncemented STAR total ankle prostheses. Three to eight-year follow-up of fifty-one consecutive ankles.

BACKGROUND: The feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR). METHODS: Between 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant. RESULTS: Twelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032). CONCLUSIONS: Total ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement.

Adult↗
PubMed2002

Primary hemiarthroplasty in old patients with displaced femoral neck fracture: a 1-year follow-up of 103 patients aged 80 years or more.

103 patients with displaced femoral neck fractures (Garden 3-4) treated with primary hemiarthroplasty in the Department of Orthopedics, Malmö University Hospital, Sweden 1998-1999 were followed in a prospective, consecutive study for 1 year. Inclusion criteria were age of at least 80 years, signs of mental changes and/or residence in an institution. The control group consisted of 69 patients with internal fixation (Hansson hook pins). The arthroplasty group required more blood transfusions, a longer operation and had more superficial infections. No differences were detected as regards other complications, length of hospital stay, in-hospital mortality or ability to return home. The 1-year mortality rates were similar in the arthroplasty (29/103) and control groups (28/69). Within 1 year, we found a lower failure rate in the arthroplasty group (6/103) than in the control group (18/69). In the arthroplasty group, 2/103 had dislocations. Of the surviving arthroplasty patients at 12 months, 31/74 could walk as well as before the fracture and 55/74 had no pain. We recommend primary hemiarthroplasty for demented and/or institutionalized patients over 80 years with displaced femoral neck fractures.

Age Factors↗
PubMed2002

Arthrodesis of the ankle for non-inflammatory conditions--healing and reliability of outcome measurements.

This is a retrospective study of 30 consecutive primary ankle arthrodeses in 29 patients with osteoarthrosis, operated on in our hospital between 1984 and 1994. Two different techniques were utilized: internal fixation with screws or external fixation using Charnley or Hoffman frames. Only 25 ankles in 24 patients were available for clinical examination. They were examined by two independent surgeons on an average of 51 months after surgery (13 to 187 months). Two radiologists separately examined the radiographs that were available--in this case, 29 ankles, without knowledge of clinical data, and 26/29 (89%) were unanimously considered as fused. This is comparable with what is reported in other series. Unanimity among all four observers regarding healing of the arthrodesis occurred in 20/25 ankles (80%). We consider that both a radiological and a clinical evaluation is important for a fair judgement of fusion. We found high consistency among the observers with respect to the clinical scores. However, the consistency was somewhat better for the Mazur than for the Kofoed system.

Adult↗