Ventralight ST and Sorbafix versus Physiomesh and Securestrap in a porcine model

BACKGROUND AND OBJECTIVES: The objective of this study was to compare mesh contracture, adhesion characteristics, tissue ingrowth, and histologic response of Ventralight ST/SorbaFix (C.R. Bard/Davol, Warwick, RI, USA) with Physiomesh/Securestrap (Ethicon, Somerville, NJ, USA) in a porcine model of laparoscopic ventral hernia repair. METHODS: Standard laparoscopic technique was used to bilaterally implant meshes in 10 female Yorkshire swine. Each animal received either two Ventralight ST meshes (oval shaped, 10.2 × 15.2 cm) or two Physiomesh meshes (oval shaped 10 × 15 cm), one on either side of the midline. The meshes were fixated to the intact peritoneum with either SorbaFix (for animals receiving Ventralight ST) or Securestrap (for animals receiving Physiomesh). There were 5 animals in each group, yielding 10 of each mesh-fixation combination. Mesh contracture, adhesion characteristics, tissue ingrowth, and histologic response were evaluated after 14 days by image analysis, mechanical testing, and histologic staining (hematoxylin-eosin, Masson trichrome, picrosirius red, and von Willebrand factor). RESULTS: Ventralight ST/SorbaFix and Physiomesh/Securestrap exhibited a similar percentage of mesh contracture, percentage of adhesion coverage, adhesion tenacity, collagen deposition, and levels of necrosis (P > .05 in all cases). However, Ventralight ST/SorbaFix exhibited significantly less inflammation (P = .0001), fibrosis (P = .0017), hemorrhage (P = .0001), and angiogenesis (P = .0032) and significantly greater strength of tissue ingrowth (P = .0003) than Physiomesh/Securestrap after the 14-day implantation period. CONCLUSIONS: Ventralight ST/SorbaFix exhibited more favorable strength of tissue ingrowth and histologic response and similar mesh contracture and adhesion characteristics compared with Physiomesh/Securestrap over a short-term 14-day implantation period in a preclinical porcine model

Comminuted patella fracture in elderly patients: a systematic review and case report

Objectives: To review comminuted patella fracture in the elderly patients and examine the surgical options to avoid compli-cations such as fixation failure and poor functional outcome. To provide an example of mesh augmentation in comminuted patellafracture in the elderly patients. Data Sources: A literature review was conducted by the authors independently using Ovid,Medline, Cochrane, PubMed, and Clinical Key in English. We aimed to review data on patients older than 65 with comminutedpatella fracture. Search conducted between July and December 2015. Study Selection: Search terms included patella fracture,elderly, and fixation failure. Abstracts were included if they were a case report, cohort series, or randomized control trial. Furtherinclusion criteria were that they were available in full text and included patient age(s), operative details, follow-up, and outcomediscussion. Data Extraction: Each study was assessed according to its level of evidence, number of patients, age of patients,fracture patterns described, complications of treatment, and results summarized. Data Synthesis: Paucity of data and het-erogeneity of studies limited statistical analysis. Data are presented as a review table with the key points summarized. Conclusion:In patella fracture, age >65 years and comminuted fracture pattern are predictors of increased fixation failure andpostoperative stiffness, warranting special consideration. There is a trend toward improved functional outcomes when aug-mented fixation using mesh or plates is used in this group. Further level 1 studies are required to compare and validate newtreatment options and compared them to standard surgical technique of tension band wire construc

Total knee arthroplasty in patients with extra-articular deformity

AbstractMultiple acceptable options are available for the correction of distal femoral deformity associated with knee arthritis. The treatment modality should be chosen based on the extent of deformity and attention to preservation of the collateral ligaments. Surgical options range from osteotomy alone, arthroplasty with intra-articular correction, or arthroplasty with extra-articular correction. Different implant choices and fixation methods for the osteotomy possess advantages and disadvantages which need to be considered carefully. In addition to discussing principles of management based on current literature, this article includes a case report using a previously undescribed technique using corrective osteotomy, intramedullary nail fixation, and total knee arthroplasty with computer navigation

Ariel - Volume 7 Number 2

Editors Mark Dembert Frank Chervanek John Lammie Jim Burke Curt Cumming

Comparison between 2 types of radiofrequency ablation systems in arthroscopic rotator cuff repair: a randomized controlled trial

BACKGROUND: Radiofrequency ablation is commonly used in arthroscopic rotator cuff repair (RCR). New technology devices incorporating a plasma bubble may generate lower intra-articular temperatures and be more efficient. PURPOSE: To compare a plasma ablation device with a standard ablation device in arthroscopic RCR to determine which system is superior in terms of intra-articular heat generation and diathermy efficiency. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: This was a single-center randomized controlled trial. The inclusion criteria were adult patients undergoing primary RCR. Patients were randomized preoperatively to the standard ablation group (n = 20) or plasma ablation group (n = 20). A thermometer was inserted into the shoulder joint during surgery, and the temperature, surgery, and diathermy times of radiofrequency ablation were measured continually. RESULTS: No significant differences were found between the standard ablation group and plasma ablation group for maximum temperature (38.20°C and 39.38°C, respectively; P = .433), mean temperature (31.66°C and 30.64°C, respectively; P = .757), minimum temperature (21.83°C and 23.45°C, respectively; P = .584), and baseline temperature (28.49°C and 29.94°C, respectively; P = .379). Similarly, no significant differences were found for surgery time (74 and 75 minutes, respectively; P = .866) and diathermy time (10 minutes for both; P = .678). Seven patients registered transient high temperatures greater than 45°C. CONCLUSION: There was no difference between plasma ablation and standard ablation in terms of intra-articular temperature in the joint and diathermy efficiency. Transient high intra-articular temperatures occurred in both groups

Problems and shortcuts in deep learning for screening mammography

This work reveals undiscovered challenges in the performance and generalizability of deep learning models. We (1) identify spurious shortcuts and evaluation issues that can inflate performance and (2) propose training and analysis methods to address them. We trained an AI model to classify cancer on a retrospective dataset of 120,112 US exams (3,467 cancers) acquired from 2008 to 2017 and 16,693 UK exams (5,655 cancers) acquired from 2011 to 2015. We evaluated on a screening mammography test set of 11,593 US exams (102 cancers; 7,594 women; age 57.1 \pm 11.0) and 1,880 UK exams (590 cancers; 1,745 women; age 63.3 \pm 7.2). A model trained on images of only view markers (no breast) achieved a 0.691 AUC. The original model trained on both datasets achieved a 0.945 AUC on the combined US+UK dataset but paradoxically only 0.838 and 0.892 on the US and UK datasets, respectively. Sampling cancers equally from both datasets during training mitigated this shortcut. A similar AUC paradox (0.903) occurred when evaluating diagnostic exams vs screening exams (0.862 vs 0.861, respectively). Removing diagnostic exams during training alleviated this bias. Finally, the model did not exhibit the AUC paradox over scanner models but still exhibited a bias toward Selenia Dimension (SD) over Hologic Selenia (HS) exams. Analysis showed that this AUC paradox occurred when a dataset attribute had values with a higher cancer prevalence (dataset bias) and the model consequently assigned a higher probability to these attribute values (model bias). Stratification and balancing cancer prevalence can mitigate shortcuts during evaluation. Dataset and model bias can introduce shortcuts and the AUC paradox, potentially pervasive issues within the healthcare AI space. Our methods can verify and mitigate shortcuts while providing a clear understanding of performance

In vivo arthroscopic temperatures: a comparison between 2 types of radiofrequency ablation systems in arthroscopic anterior cruciate ligament reconstruction—a randomized controlled trial

Purpose: To compare a plasma ablation device with a standard ablation device in anterior cruciate ligament (ACL) reconstruction to determine which system is superior in terms of intra-articular heat generation and diathermy efficiency. Methods: This was a prospective, randomized controlled trial. The inclusion criteria were adult patients undergoing primary ACL reconstruction. Patients were randomized preoperatively to the standard ablation group or the plasma ablation group. A thermometer was inserted into the inferior suprapatellar pouch, and the temperature, time, and duration of radiofrequency ablation were measured continually. Results: No significant differences were found between the standard ablation system and the plasma ablation system for maximum temperature (29.77°C and 29.34°C, respectively; P =.95), mean temperature (26.16°C and 26.99°C, respectively; P =.44), minimum temperature (22.66°C and 23.94°C, respectively; P =.54), and baseline temperature (26.80°C and 27.93°C, respectively; P =.35). Similarly, no significant differences were found for operative time (82.90 minutes and 80.50 minutes, respectively; P =.72) and mean diathermy activation times (2.6 minutes for both systems; P =.90). The between-system coefficient of variation for the measured parameters ranged from 0.12% to 3.69%. No intra-articular readings above the temperature likely to damage chondrocytes were recorded. The mean irrigation fluid temperature had a significant correlation with the maximum temperature reached during the procedure (Spearman rank correlation, r = 0.87; P < .01). Conclusions: No difference in temperature was observed between the standard ablation and plasma ablation probes during ACL reconstruction. Temperatures did not exceed critical temperatures associated with chondrocyte death. Level of Evidence Level I, randomized controlled trial