Biomedical subjects

Ate B Wymenga

Publications and source records attributed to Ate B Wymenga.

6 recordsLinked to original sources

PubMed2006

A new CT scan method for measuring the tibial tubercle trochlear groove distance in patellar instability.

Patellar malalignment leading to objective or potential patella instability can be caused by tibial tuberosity lateralisation. This can be treated with a tuberosity medialisation. CT scan measurements are needed to assess the tibial tubercle trochlear groove distance. When using the previously described methods to determine this distance it can be difficult to determine the anatomical structures on the maximum intensity projection images, and this can lead to measurement error. This study was designed to compare the reliability of a new computer based CT measurement to the previously described method to determine the tibial tubercle trochlear groove distance. For each method, four observers measured each of 50 knees twice. The inter- and intra-observer variability for the conventional method and a new method were determined. Using the conventional method, the number of knees for which the difference between the aggregate mean of all eight measurements and the mean of duplicate measurements per observer greater than 2 mm varied among the observers between 7 and 24 for the 50 knees, while this variation between four and seven for the same 50 knees using the new method. The limits of reproducibility based on measurements from the four different observers improved by 25%, indicating that the measurement error is considerably smaller with the new method. We advise using this more accurate method to improve the selection of patients for a tuberosity medialisation.

Cohort Studies↗

PubMed2006

Conventional radiography cannot replace CT scanning in detecting tibial tubercle lateralisation.

Patellar instability can be caused by an excessive lateral distance between the anterior tibial tubercle and the trochlear groove (TT-TG). This study was designed to compare the TT-TG in reformatted computed tomography to the TT-TG on a 30 degrees axial conventional radiograph (CR) using lead markers to visualize the tibial tubercle and epicondyles. This is the first report on the use of lead markers for determining the TT-TG. Seven symptomatic knees in five patients (mean age 25 years, standard deviation 8.0 years) were investigated. Results showed that the tibial tubercle could be detected on 30 degrees axial CR by a lead marker. Determining the TT-TG however proved to be difficult. A good intra- and interobserver reliability (ICC >0.86) but large measurement error for the axial CR compared to CT was measured (Limits of Reproducibility as quantification of the measurement error was 18 mm for axial CR and 4 mm for CT). Because of the large measurement error for axial CR, the study was terminated after seven symptomatic knees. Positioning of the patient and markers, especially the tibial tubercle marker, probably are important factors leading to the large measurement error. Therefore, axial CR cannot replace CT to detect a pathological tubercle trochlear groove distance.

Adolescent↗

PubMed2005

The use of the knee joint-line balancer to control patella position in revision total knee arthroplasty.

In revision total knee arthroplasty (TKA), control of the patellar height and the joint line is difficult. Therefore, we developed an adjustable flexion-extension spacer, the Knee Joint-line Balancer (KJB(R)). This device simulates femur component sizes, polyethylene sizes, the joint-line level, and distal femur wedges. The goal of this study is to evaluate the use of an adjustable knee spacer to control patellar height and joint-line during revision total knee surgery. The subjects of the study were the first 10 consecutive patients who had undergone revision of a primary TKA where the KJB was used. A reference group composed of the last 10 patients treated without the use of the KJB was also evaluated. The joint-line position and the patellar height were determined before and after revision TKA. The method described by Figgie et al. was used. The patellar height in the reference group averaged 7.7 mm. Seven of 10 patients had a patella baja, and two of these patients had patellar impingement. One patient needed a proximalisation of the tuberositas. The patellar height in the KJB group averaged 14.6 mm after revision, with only one patient having a patella baja. This new device, adjustable kneespacer for revision TKA ("the KJB"), seems to provide better control of the patellar position in total knee revision.

Aged↗

PubMed2005

Retention versus removal of the posterior cruciate ligament in total knee replacement: a systematic literature review within the Cochrane framework.

BACKGROUND: There is no consensus as to whether to use a posterior cruciate ligament (PCL) retaining design or a posterior-stabilized design for total knee arthroplasty. The objective of this study was to establish the difference in functional, clinical, and radiological outcome between retention and removal of the PCL. METHODS: We conducted a search in Medline, EMBASE, the Cochrane database, and Current Contents, along with reference checks and citation tracking. Randomized controlled trials were selected and methodological quality was assessed with the van Tulder and Jadad checklists by 2 independent reviewers. RESULTS: We found 8 randomized controlled trials. 2 treatment options were compared against PCL retention: PCL removal without post and cam mechanism (2 studies), and posterior-stabilized design (5 studies). 1 study included all 3 options. Range of motion was found to be 8 degrees higher (105 degrees vs. 113 degrees ) in the posterior-stabilized group compared to the PCL retention group (p = 0.01, 95% CI (1.7, 15)). INTERPRETATION: These results should be interpreted with caution, as the methodological quality of the studies was highly variable. Suggestions are given to improve future research on this specific aspect of knee arthroplasty.

Arthroplasty, Replacement, Hip↗

PubMed2004

Tricalcium phosphate granules or rigid wedge preforms in open wedge high tibial osteotomy: a radiological study with a new evaluation system.

The capacity of two forms of porous beta-tricalcium phosphate bone substitutes (TCP) to promote bone healing in open wedge high tibial osteotomy (OWHTO) was studied. We reviewed the X-rays of 27 osteotomies, with either TCP wedges or TCP granules as filling material, to compare the bone healing rates and bone remodelling, at specific postoperative intervals. A new radiologic rating system for OWHTO was created and tested for clinical applicability. All osteotomies healed uneventfully and complete resorption of TCP was demonstrated at 1 year postoperative in 85% (n = 23) of the procedures. In 44% (n = 10) of these 23 procedures, the osteotomy site was no longer visible. No difference in bone healing rate and bone remodelling was found when comparing the use of granules to a wedge, and no adverse effects of TCP were observed. The good inter- (k = 0.7) and intraobserver (k = 0.6) reliability of the new radiologic rating system enables clinical use. Good bone healing was found in OWHTO with both wedges and granules of TCP.

Adult↗

PubMed2003

Potential healing benefit of an osteoperiosteal bone plug from the proximal tibia on a mosaicplasty donor-site defect in the knee. An experimental study in the goat.

INTRODUCTION: Autologous osteochondral transplantation is a popular treatment for articular cartilage lesions in the knee joint. The donor defect is commonly left empty and remains a matter of concern. MATERIALS AND METHODS: In 20 knees of 10 goats, we created a standardised donor defect in the knee. In the control group the defects were left empty, whereas in two other groups a bone plug from the proximal tibia was press-fitted into the defect with or without a covering periosteal layer. RESULTS: Histological evaluation after 8 and 16 weeks showed that relatively rapid osteoclastic resorption of the bone plug occurred. Defects were mainly filled with fibrous tissue, and collapse of the adjacent bone and cartilage was visible, especially when the defects were left empty. Occasionally, some consolidation of the graft to the host bone could be detected, and in some samples periosteal chondrogenesis was present. CONCLUSION: Our findings suggest that transplantation of a tibial bone plug with covering periosteum to the donor defect in a cartilage transplantation procedure does not have any additional value in an attempt to minimise the damage at the donor site. The observed resorption of the bone plug and the collapse of the adjacent joint margin remain a matter of concern with this technique.

Animals↗