CASE PRESENTATION: A 57-year-old man presented to our orthopedic outpatient department with 3-months history of an unusual painful swelling at the operated area following DFO. The leakage of joint fluid from the penetrated suprapatellar pouch was assumed to be the reason for this complication.
CONCLUSIONS: The overall aim of this case report is to provide a lesson to budding surgeons who might experience a similar situation that cannot be easily explained, like the unexpected complication in the present case.
METHODS: Fifty-three formalin-fixed, paraffin-embedded nasopharyngeal carcinoma tissue blocks were chosen for this study. The presence of Epstein-Barr virus (EBV) was determined by in situ hybridisation using an EBER probe. p53 protein expression was detected using immunohistochemistry. Simultaneously, amplifications by PCR were performed for p53 exons 5 to 8, followed by mutation screening via single strand conformation polymorphism (SSCP). Sequencing of all the four exons was performed in five samples with mobility shift. To rule out false negative results by SSCP, 13 samples with p53 overexpression and five samples with low p53 expression were randomly selected and sequenced.
RESULTS: There was no mutation found in exons 5 to 8 in all the samples despite 46 (87%) of them having high p53 levels. EBV was detected in 51 (96%) out of 53 samples. There was no statistically significant association between p53 expression level and EBV presence.
CONCLUSIONS: High-intensity staining for p53 by immunohistochemistry was common in our series of NPC tissue samples but was not associated with 'hot spot' mutations of exons 5-8 of the gene. We did not find a significant relationship between the expression level of p53 and presence of EBV. Our study confirms that mutation of the DNA-binding domain of p53 is rare in NPC.
METHODS: A total of 137 patients with 212 consecutive knees who underwent TKAs with or without functional stepwise MNP of superficial medial collateral ligament was recruited in this prospective cohort. Eighty-one patients with 129 knees who performed serial stress radiographs were enrolled in the final assessment. Superficial medial collateral ligament was punctured selectively (anteriorly or posteriorly or both) and sequentially depending on the site and degree of tightness. Mediolateral stability was assessed using serial stress radiographs and comparison was performed between the MNP and the non-MNP groups at postoperative 6 months and 1 year. Clinical outcomes were also evaluated between 2 groups.
RESULTS: Fifty-five TKAs required additional stepwise MNP (anterior needling 19, posterior needling 3, both anterior and posterior needling 33). Preoperative hip-knee-ankle angle and the difference in varus-valgus stress angle showed significant difference between the MNP and the non-MNP groups, respectively (P = .009, P = .037). However, there was no significant difference when comparing the varus-valgus stress angle between the MNP and the non-MNP groups during serial assessment. Clinical outcomes including range of motion also showed no significant differences between the 2 groups.
CONCLUSION: Functional medial ligament balancing with stepwise MNP can provide sufficient medial release with safety in TKA with varus aligned knee without clinical deterioration or complication such as instability.
LEVEL OF EVIDENCE: Level II, Prospective cohort study.
METHODS: This single-blind, prospective, randomized, controlled trial involved intraoperative measurements for 271 femoral component implantations from 3 contemporary TKA systems, with 2 systems offering narrow sizing options. The difference between femoral component dimensions and the resected surface of distal femur was measured in millimeters at 5 distinct zones.
RESULTS: Overhang of standard femoral component was common in the anterior-medial condyle and anterior-lateral condyle ranging from 50.8% to 99.0% and 21.5% to 88.0%, respectively. With narrow femoral components, the rate of overhang reduced to 21.5%-30.2% and 9.2%-32.1%. Conversely, underhang rates were higher over the anterior flange width, middle medial-lateral and posterior medial-lateral zones. Standard components displayed higher underhang rates at these zones compared to narrow components. The good fit rate for femoral component was low among the 3 systems ranging from 1.0% to 56.0%. System with narrow option sizing increases the underhang rates in males, while improving the component fit among females at similar zones with rate ranging from 5.2% to 52.9%.
CONCLUSION: Currently available TKA implant designs may not provide a perfect match for the distal femoral shape of the Korean population. The availability of implants with standard and narrow options can substantially improve the optimal fitting of femoral components in the Korean population.