Accuracy of knee implants sizing predicted by digital images.

BACKGROUND: Accurate preoperative templating to predict implant size and position can facilitate precise, efficient, and reproducible knee replacement operations. Preoperative templating for total knee arthroplasty can be performed with digital images of the knee implants on digital radiographs of the knee. OBJECTIVE: To determine the accuracy of knee implants sizing predicted by digital images. MATERIAL AND METHOD: A retrospective study was done to assess the accuracy of the knee implant sizing predicted by digital images in 100 Thai adults, who had osteoarthritis of the knee. Digital anteroposterior and lateral radiographs of the knee were used in measuring the level of distal femoral resection and the level of proximal tibial resection. Anteroposterior and mediolateral diameter of femur and tibia were determined and the implant size was choosen. The results from digital images were compared with the size of actual femoral and tibial implants used at the time of surgery. All variables were analyzed. The correlation coefficients were calculated to determine interobserver and intraobserver reliability. RESULTS: The accuracy of digital preoperative plans for femoral component was 53.1%. The accuracy of digital preoperative plans for tibial component was 59.3%. The digital preoperative planning predicted 79 of 81 (97.6%) femoral implants to within one size and predicted 77 of 81 (95.1%) measurements of the tibial implants to within one size. CONCLUSION: Digital images can help to focus the thoughts and plans of the operation. When planning is performed, it can identify extremes of sizes that may require special order, and planning can predict size mismatches between femoral and tibial implants. When recognized ahead of time, these limitations can be accommodated during the surgical procedure or a different implant system chosen. Predicting implant sizes to within one size allows efficient anticipation by the orthopaedic surgeon.

Association of estrogen receptor-alpha single-nucleotide polymorphism (codon 594 G-->A) and Thai patients affected by knee osteoarthritis.

BACKGROUND: Estrogen receptor-alpha single-nucleotide polymorphism (ER-alpha SNP) has previously shown its susceptibility to knee osteoarthritis (OA) but this association cannot be applied to ethnic groups with different genetic backgrounds. OBJECTIVE: To characterize the genetic association between ER-alpha SNP and knee OA in the Thai. MATERIAL AND METHOD: A case-control study was conducted at Ramathibodi Hospital from August 2007 to May 2008. Altogether, 104 cases affected by knee OA and 104 controls were included in this study. SNP rs2228480 (codon 594 G!A) on the ER-alpha gene was genotyped by a PCR-RFLP-based technique. Genotype frequencies were analyzed by logistic regression. RESULTS: ER-alpha SNP was normally distributed through the Hardy-Weinberg Equilibrium (HWE). The risk of knee OA was genetically associated to AG an AA genotypes compàred with homozygous wild-type GG (OR: 1.02, 95% CI: 0.60-1.80 for AG; OR: 1.27, 95% CI: 0.30-4.90 for AA). CONCLUSION: Our study showed that these genetic alterations might be associated with knee osteoarthritis in the Thai population. Further investigation on other informative SNPs on the ER-alpha gene should be performed to create a reliable haplotype that might provide a stronger link between genetic profiles and clinical picture.

Comparison of Synovial Fluid and Serum Procalcitonin for Diagnosis of Periprosthetic Joint Infection: A Pilot Study in 32 Patients.

BACKGROUND: Periprosthetic joint infection (PJI) remains challenging since a "gold standard" for diagnosis has not yet been established. This study aimed to evaluate the accuracy of synovial fluid procalcitonin (SF-PCT) and serum procalcitonin as a diagnostic biomarker for PJI and to compare its accuracy against standard methods. METHODS: A prospective cohort study was conducted during 2015-2017 in 32 patients with painful hip or knee arthroplasty who have underwent revision surgery. Relevant clinical and laboratory data were collected. PJI was diagnosed based on the 2013 international consensus criteria. Preoperative blood sample and intraoperatively acquired joint fluid were taken for PCT measurement with a standard assay. Diagnostic accuracy was analyzed by the receiver-operating characteristic curve and the area under the curve (AUC). RESULTS: Twenty patients (62.5%) were classified as the PJI group, and 12 (37.5%) were classified as the aseptic loosening group. The median age was 68 years (range 38-87 years). The median values of SF-PCT and serum PCT in the PJI group were both significantly higher than those in the aseptic loosening group: the median serum PCT levels (interquartile range: IQR) were 0.33 ng/mL (0.08-2.79 ng/mL) in the PJI group compared with 0.04 ng/mL (0.03-0.06 ng/mL), and the median SF-PCT levels (IQR) were 0.16 ng/mL (0.12-0.26 ng/mL) in PJI group compared with 0.00 (0.00-0.00 ng/mL) (p < 0.001, both). SF-PCT, with a cut-off level of 0.08 ng/mL, had an AUC of 0.87, a sensitivity of 90.0%, a specificity of 83.3%, and a negative likelihood ratio (LR-) of 0.12. Serum PCT, with a standard cut-off level of 0.5 ng/mL, had an AUC of 0.70, a sensitivity of 40.0%, a specificity of 100.0%, and a LR- of 0.60. CONCLUSION: SF-PCT appears to be a reliable test and could be useful as an alternative indicator or in combination with standard methods for diagnosing PJI.

Flexor tendon rupture after distal radius fracture. Report of 2 cases.

Flexor tendon rupture after distal radius fracture is very rare. The authors reported two cases. The first case had flexor pollicis longus tendon rupture. The other had flexor pollicis longus and multiple finger flexor tendons rupture. The authors propose two modes of mechanism of tendon rupture after distal radius fracture.

Postoperative blood loss reduction in computer-assisted surgery total knee replacement by low dose intra-articular tranexamic acid injection together with 2-hour clamp drain: a prospective triple-blinded randomized controlled trial.

A high-dose local tranexamic acid has been introduced in total knee arthroplasty for bleeding control. We are not sure about the systemic absorption and side effects. The aim of this study was to evaluate the effect of low dosage of intra-articular tranexamic acid injection combined with 2-hour clamp drain in minimally bleeding computer-assisted surgery total knee replacement (CAS-TKR). A prospective randomized controlled trial was conducted in a total of 48 patients underwent CAS-TKR. The patients were randomly assigned to receive either of a mixed intra-articular solution of tranexamic acid 250 mg with physiologic saline (TXA group), or physiologic saline (control group) and then followed by clamp drain for 2 hours. Postoperative blood loss was measured by three different methods as drainage volume, total hemoglobin loss and calculated total blood loss. Transfusion requirement and postoperative complications were recorded. All patients were screened for deep vein thrombosis and the functional outcomes were evaluated at 6 months after surgery. The mean postoperative drainage volume, total hemoglobin loss and calculated total blood loss in TXA group were 308.8 mL, 2.1 g/dL and 206.3 mL compared to 529.0 mL, 3.0 g/dL and 385.1 mL in the control group (P=0.0003, 0.0005 and <0.0001 respectively). Allogenic blood transfusion was needed for one patient (4.2%) in TXA group and for eight patients (33.3%) in the control group. Postoperative knee scores were not significantly different between groups. No deep vein thrombosis, infection or wound complication was detected in both groups. In this study, low dose intra-articular tranexamic acid injection combined with 2-hour clamping drain was effective for reducing postoperative blood loss and transfusion requirement in CAS-TKR without significant difference in postoperative complications or functional outcomes.