Vajara Wilairatana

Plasma and synovial fluid sclerostin are inversely associated with radiographic severity of knee osteoarthritis

OBJECTIVE The purpose of this study was to analyze sclerostin in plasma and synovial fluid of knee osteoarthritis (OA) patients and to investigate the association between sclerostin levels and radiographic severity. DESIGN AND METHODS A total of 190 subjects (95 knee OA patients and 95 healthy controls) were recruited in the present study. Sclerostin levels in plasma and synovial fluid were assessed using an enzyme-linked immunosorbent assay. OA grading was performed using the Kellgren-Lawrence classification. RESULTS Plasma sclerostin levels were significantly lower in OA patients than in healthy controls (P=0.004). Additionally, sclerostin levels in plasma were significantly higher with respect to paired synovial fluid (P<0.001). Moreover, sclerostin levels in plasma and synovial fluid demonstrated a significant inverse correlation with the radiographic severity of knee OA (r=-0.464, P<0.001 and r=-0.592, P<0.001, respectively). Subsequent analysis revealed that there was a positive correlation between plasma and synovial sclerostin levels (r=0.657, P<0.001). CONCLUSIONS Sclerostin was significantly lower in OA plasma samples when compared with healthy controls. Plasma and synovial fluid sclerostin levels were inversely associated with the radiographic severity of knee OA. Therefore, sclerostin may be utilized as a biochemical marker for reflecting disease severity in primary knee OA.

Plasma and synovial fluid inflammatory cytokine profiles in primary knee osteoarthritis.

Abstract Objective: The objective of this study is to compare inflammatory cytokine levels in primary knee osteoarthritis (OA) patients and healthy controls. Methods: A total of 32 knee OA patients and 14 healthy controls were enrolled. A multiplex immunoassay was utilized for 10 cytokines in plasma and synovial fluid. Results: Plasma IL-2, IL-4, and IL-6 concentrations were significantly greater in knee OA patients than controls. Moreover, both plasma IL-4 and IL-6 were positively correlated with the radiographic severity of knee OA. Conclusions: Plasma IL-4 and IL-6 may serve as biomarkers reflecting the severity of OA.

Gap changes after popliteus-tendon resection in PS-TKA: A cadaveric study in Thai female knees

Popliteus-tendon injury during total knee arthroplasty (TKA) may result in imbalanced soft-tissue tension; however, it is unclear whether complete popliteus-tendon resection is a factor which contributes to knee instability following TKA. We performed an isolated complete resection of the popliteus tendon during a standard posterior stabilised TKA (PS-TKA) in 14 normal knees of Thai female cadavers and measured gap differences in both knee flexion and extension. In addition, we measured the distance from the femoral attachment of the popliteus tendon to the femoral condyles including the distance from the most distal femoral attachment of the popliteus tendon to the distal lateral femoral condyle (DFa-DLFC), and the distance from the most posterior femoral attachment of the popliteus tendon to the posterior lateral femoral condyle (PFa-PLFC). After completion of bone cuts, static flexion and extension gaps were measured with a tension of 98 N under intact and complete tendon resection, respectively. The mean DFa-DLFC and PFa-PLFC distances were 8.9 mm (range, 6.4-10.5mm) and 11.5mm (range, 9.5-14.0mm), respectively. Of 14 cadaveric knees, 35.7% had a DFa-DLFC distance <9 mm. Flexion and extension gaps significantly increased in both medial and lateral sides after complete popliteus resection with a similar mean increased value of 1.85 mm. The clinical evaluation of gap changes after popliteus resection on knee stability should be further investigated. A routine 9-mm distal femoral bone cut may injure the popliteus tendon during TKA conducted on small knees.

Spontaneous Acetabular Periprosthetic Fracture in a Patient Continuously Having Zoledronic Acid

Zoledronic acid has been used for prevention of osteolytic and osteoblastic bone metastasis. This case report illustrates an undesirable consequence from prolonged usage of zoledronic acid in bone metastasis prevention. Periprosthetic acetabular fracture in a patient treated with zoledronic acid for 7 years was reported. The clinical presentation, radiographic and pathological results were described. This is a rare complication after total hip arthroplasty which should not be ignored especially in patients who received long term bisphosphonate.

Anterior greater trochanteric muscle pedicle bone grafting: a viable graft option adjunct to hip osteotomy or fracture surgery

Introduction The objectives were to evaluate a technique, outcome and complications following anterior greater trochanteric with gluteus medius muscle pedicle bone graft (AMG) procedure in the treatment of adolescent and active adult hip disorders. Methods 20 patients (20 hips) with a mean age of 22.7 ± 15.6 (range 10.0-63.5) years who had undergone AMG and been followed up more than 12 months postoperative were retrospectively enrolled in our study. The AMG procedure was performed in conjunction with subcapital osteotomy for slipped capital femoral epiphysis in 12 and open reduction for fracture/dislocation in 8 hips. At the most recent evaluation, patient functional status was rated by the Harris Hip Score (HHS) and radiographic changes were graded according to Tönnis criteria. Complications were defined as Tönnis grade >2 or hip requiring further surgery. Univariate analysis was used to explore factors associated with complications. Spearmans rank correlation coefficient was calculated between HHS and Tönnis grading. Results At mean follow-up of 4.4 ± 2.6 (range 1.1-9.5) years, mean HHS was 87.4. Tönnis grading was rated as 0 in 10 hips, 1 in 5 hips, 2 in 2 hips, and 3 in 3 hips. Avascular necrosis of the femoral head as a complication developed in 3 hips (15%). Clinical parameters including age at surgery, duration of follow-up and diagnosis were not significantly associated with postoperative complications. A negative correlation between HHS and Tönnis grade was shown by Spearmans rank correlation (rs = −0.49, p = 0.03). Conclusions The AMG can be safely recommended as an adjunct bone graft procedure when performing anterior open reduction of adolescent and active adult hip disorders.

Effects of Cemented Hip Stem Pre‐heating on Stem Push‐out Strength

To determine the effect on ultimate push‐out load and cement–stem surface shear strength of thermally manipulating the cobalt‐chromium‐molybdenum (CoCrMo) alloy stems of bone cement–stem constructs.

Accuracy of computer-assisted total knee arthroplasty related to extra-articular tibial deformities.

Abstract Objective: To compare the accuracy of postoperative mechanical alignment in computer-assisted total knee arthroplasties (CAS-TKA) related to various degrees of extra-articular tibial deformity. Methods: We performed CAS-TKA on 30 knee models in which extra-articular proximal tibial deformities were preset to have malalignments ranging from 30° of varus to 30° of valgus. The knees were assigned to two groups, designated Group A (knees with ≤15° preoperative malalignment) and Group B (knees with >15° preoperative malalignment), and the postoperative mechanical alignment in the two groups was compared using a computer-assisted surgery (CAS) system. Resected bone pieces from the distal femurs and proximal tibias were measured with a digital Vernier caliper and the results compared with the CAS calculations to evaluate the execution accuracy of the bone resection. Results: There was no outlier in either group when a ±3° deviation from neutral mechanical alignment was set as the acceptance criterion. Interestingly, Group B showed significantly more outliers when the acceptance criterion was a deviation of ±2° (26.67%, p = 0.0317) or ±1° (6.67%, p = 0.0007) from neutral alignment. There was no statistical difference between the groups in terms of the execution accuracy of the bone resection. Discussion: The CAS-TKA approach provided significantly less alignment accuracy in tibia with greater preoperative frontal deformity, despite there being no outliers beyond ±3°.

Clinical report. Atypical acetabular bone loss in chronic septic total hip arthroplasty loosening

Abstract Background: When a periprosthetic infection is diagnosed, the surgical treatment is usually performed as soon as possible to avoid further bone damage or life threatening complications. There is no report on the radiographic change in patients with untreated infected total hip arthroplasty (THA) for several years. Objective: Report radiographic change in patients with untreated infected THA. Method: Two patients presented with chronic septic loosening of cemented acetabular fixation after total hip replacement at King Chulalongkorn Memorial Hospital. Both patients had mild hip pain and had been lost for follow-up until the bone destruction became very severe. Serial radiographs after the surgeries were evaluated. The Paprosky’s acetabular bone loss classification was used to classify the radiographic findings. Results: Based on the Paprosky’s classification for acetabular bone loss, there were two similar atypical radiographic findings found in both patients. These included pelvic discontinuity from extensive medial acetabular bone loss beyond the Kohler’s line, and minimal superior and inferior acetabular bone loss. Conclusion: These atypical radiographic findings were rarely observed in septic acetabular loosening patients, as infection usually causes patients to present earlier. Following the septic acetabular loosening of THA, surgical procedure should be performed before massive bone damage was demonstrated.