No improvement in reducing outliers in coronal axis alignment with patient-specific instrumentation.

PURPOSE AND HYPOTHESIS: Patient-specific instrumentation (PSI) uses 3D preoperative imaging to produce individualized cutting blocks specific to patients' anatomy and according to the preoperative plan with the aim to reduce the number of mechanical leg alignment (MLA) outliers, to improve implant positioning and to decrease surgery time. The primary purpose of this study was to investigate the efficacy of a specific PSI in comparison with standard instrumentation (SI) in reducing the number of MLA outliers. It was hypothesized that the number of MLA outliers would be significantly lower in the PSI group. METHODS: A multicenter randomized controlled trial was implemented. There were 59 patients in the PSI group and 66 in the SI group. The absolute number of outliers outside the ± 3° target neutral MLA was compared between the groups with a Chi-square test. As secondary outcomes, the Knee Society Score (KSS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were compared between the groups preoperatively and at 90-day follow-up. RESULTS: There were 15 (26.3%) MLA outliers in the PSI group and 8 (12.3%) in the SI group. The number of outliers was not independent from the group ( X2 (1) = 3.8, p = 0.04; Relative risk = 1.5). Preoperatively, there were no significant differences between the groups when comparing their KSS and KOOS sub-scores. At 90 days postoperatively, the patients in the SI group showed better KOOS-Quality of Life (KOSS-QOL) in comparison with the PSI group (p < 0.0001). CONCLUSION: The use of PSI did not significantly reduce the number of MLA outliers in comparison with SI. There were no differences when comparing the achieved mean MLA of both groups. LEVEL OF EVIDENCE: Level I, prospective randomized controlled trial.

Human papillomavirus and p53 polymorphism in codon 72 in head and neck squamous cell carcinoma.

The impact of a polymorphism of the wild-type human tumour suppressor gene p53(wt) on carcinogenesis is subject of controversy ever since a higher susceptibility of p53 to HPV-E6 mediated degradation when encoding for Arginine at codon 72 (p53Arg) was first reported. The issue remained unclear because various studies investigating this question for different tumour entities and different geographical regions demonstrated diverging results. In the present study, the HPV status and p53 genotype frequency of 42 head and neck cancers was analysed and compared to results reported in the recent literature. Applying PCR and cycle sequencing techniques, HPV DNA was demonstrated in 12/42 (29%) of the cases and the overall distribution of the p53 allele was: 64, 31 and 5% for p53Arg, p53Arg/Pro and p53Pro, respectively. There was no statistically significant association between HPV status and p53 genotype distribution. The results of our study and of the reviewed literature do not support a relevant role of the p53 polymorphism in head and neck carcinogenesis, either taken alone or in association with the HPV status.

Zenker's diverticulotomy with the carbon dioxide laser: perioperative management and long-term results.

We analyzed 119 files of patients with Zenker's diverticulum who were treated with CO2 laser systems concerning treatment management, complications, and long-term results. Although the tissue bridge was dissected down to the fundus of the diverticulum, opening the mediastinum, mediastinitis was observed in none of the cases. Of the patients followed up for long-term results, 90.3% were completely symptom-free, and 5.8% of the patients reported an improvement in general condition. In view of the low rate of complications and the low level of morbidity and because of the good functional results, microendoscopic laser surgical diverticulotomy can be recommended as suitable therapy, especially as compared to external approaches or even other endoscopic treatment strategies. The main advantage as compared to staple-assisted esophagodiverticulostomy is that no special equipment is needed and that even small pouches can be treated successfully.