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Purpose of Review: To evaluate the growing body of evidence investigating implanting a different intraocular lens (IOL) in each eye., Recent Findings: Many surgeons have turned to the mix-and-match approach of implanting two different types of IOLs with the goal of achieving an improved range of distances. A number of studies have compared different types of mix-and-match IOL approaches, with promising results that seem to show maintenance of excellent vision at all distances, and high levels of spectacle independence., Summary: The mix-and-match IOL approach appears to be a promising option for patients, maintaining good vision at all distances, especially near and intermediate, which is highly desired by patients. Few studies also showed intriguing secondary endpoints such as decreased unwanted visual phenomena using this method., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The rationale for advances in implant design is to improve performance in comparison to their predecessors. The purpose of this study was to compare a newer, self-pressurizing peripheral peg glenoid to a traditional polyethylene pegged glenoid through biomechanical evaluation and a retrospective radiographic and clinical review., Methods: Three testing conditions (uncemented, partially cemented, and fully cemented) were chosen to assess the 2 component designs in a foam block model. The number of hammer hits to seat the component, amount of time to seat the component, and resistance-to-seat were collected. The implants were then cyclically loaded following ASTM F2028-17 testing standard. Clinically, postoperative radiographs of patients with a self-pressurized glenoid component (n = 225 patients) and traditional glenoid component (n = 206 patients) were evaluated for radiolucent lines and glenoid seating at various timepoints. Clinical outcomes (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Simple Shoulder Test, and visual analog scale pain scores) and complications were recorded. The presence of radiolucent lines at the bone-cement interface was evaluated using the Modified Franklin Grade and the Lazarus grade., Results: The self-pressurizing glenoid design required significantly more hammer hits than traditional glenoid designs in all groups tested (P < .029). Moreover, the self-pressurizing design had significantly more resistance-to-seat than traditional components in both the uncemented and partially cemented group (P < .002). No difference in resistance-to-seat was found between designs in the fully cemented group. The uncemented and partially cemented groups did not survive the full 50,000 cycles; however the self-pressurizing design had significantly less motion than the traditional design (P < .001). No differences between component designs were found in the fully cemented group at 50,000 cycles. The self-pressurizing glenoid component had 0.005% radiographic radiolucent lines, and the traditional glenoid component had 45% radiographic radiolucent lines, with 38% of the radiolucencies in the traditional glenoid component group being defined as grade E. There were no progressive radiolucencies, differences in clinical outcomes, or complications at 2 years postoperatively., Conclusion: In the fully cemented condition, the 2 component designs had comparable performance; however, the differences in designs could be better observed in the uncemented group. The self-pressurizing all-polyethylene design studied has superior biomechanical stability. Clinically, the improved stability of the glenoid component correlated with a reduction of radiolucent lines and will likely lead to a reduction in glenoid component loosening., (Copyright © 2022 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background  Flexor tendon irritation or rupture following open reduction and volar plate fixation of distal radius fractures can cause significant morbidity and necessitate additional surgical intervention. Objectives  To compare the impact of the extended flexor carpi radialis (e-FCR) and standard flexor carpi radialis (FCR) approaches on contact pressures between the flexor tendons and volar distal radius plates. Methods  Eight matched pairs of fresh frozen cadavers had each limb randomized to undergo either the e-FCR or standard FCR approach. After the approach, a locking plate was applied to the volar distal radius more distally than ideally to create a worst-case scenario for the digital flexor tendons. Electronic pressure sensors were secured to the volar aspect of each locking plate. Each wrist was pinned in 20 degrees of extension during testing. Using a computer-controlled stepper motor system attached to the digital flexor and extensor tendons, the digits were taken through 4,000 cycles simulating 12 weeks of active flexion and extension. Results  There were no statistically or clinically significant differences when comparing the contact pressures of the e-FCR approach with the standard FCR approach at any time intervals. The e-FCR had statistically significantly higher radial-sided contact pressures than ulnar-sided contact pressures during early-to-intermediate testing intervals. These differences resolved at late and final testing intervals. Conclusions  When comparing the standard FCR approach with the e-FCR approach, with the wrist in 20 degrees of extension, there is no significant difference in contact pressures that occur between the digital flexor tendons and volar distal radius plates. Clinical Relevance  Further study and technique modifications may eventually lead to better methods of avoiding flexor tendon rupture during the volar plating of distal radius fractures., Competing Interests: Conflict of Interest None declared., (© Thieme Medical Publishers.)

Background/hypothesis: Suture anchor-based repair has been advocated for repair of distal triceps avulsion, but previous models have used an unequal number of sutures across the repair site. We hypothesized that there would be no difference in triceps tendon displacement between gold standard repair with transosseous cruciate bone tunnels and suture anchor repair with an equal number of sutures in the constructs., Methods: The triceps tendon footprint was measured in 20 cadaveric elbows (10 matched pairs), and a distal triceps tendon rupture was created. The specimens in each pair were randomly assigned to transosseous cruciate repair or knotless, double-row, anatomic footprint, suture anchor repair. Specimens underwent cyclic loading to 1500 cycles and then load to failure. Footprint uncoverage was measured at 1500 cycles. Data for medial and lateral triceps tendon displacement, footprint uncoverage, and failure load were obtained., Results: Triceps displacement did not differ significantly between the transosseous cruciate and the suture anchor repair group at 1500 cycles on the medial (3.6 ±  0.9 mm vs. 4.3 ± 1.6 mm [mean ± standard deviation], respectively; P = .27) and lateral side (3.1 ± 1.2 mm vs. 2.0 ± 1.2 mm, respectively; P = .06). No other differences were found between the constructs., Discussion/conclusion: Transosseous cruciate distal triceps repair and knotless double-row suture anchor repair using constructs with an equal number of sutures showed no significant difference in tendon displacement at 1500 loading cycles. These findings suggest that the biomechanical strength of an all-suture construct is not different from that of suture anchors for repair of distal triceps avulsions., (Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background: Large Achilles tendon defects pose a treatment challenge. The standard treatment with a turndown flap requires a large extensile incision, puts the sural nerve at risk, and demands slow, careful rehabilitation. Dual allograft semitendinosus reconstruction is a new clinical alternative that has the theoretical advantages of a smaller incision, less dissection, and a stronger construct that may allow for faster rehabilitation., Questions/purposes: In a cadaver biomechanical model, we compared the dual allograft semitendinosus reconstruction with the myofascial turndown in terms of (1) mechanical strength and resistance to deformation and (2) failure mechanisms in reconstruction of large segmental Achilles defects., Methods: An 8-cm segmental Achilles defect was created in 18 cadaveric lower extremities, nine matched pairs without defect or previous surgery (mean age, 78.4 years; range, 60-97 years; three female and six male pairs). Femoral neck densitometry to determine bone mineral density found that all specimens except two were osteopenic or osteoporotic. Specimens in each pair were assigned to allograft or turndown reconstruction. The constructs were mounted on a load frame and differential variable reluctance transducers were applied to measure deformation. Specimens were preconditioned and then loaded axially. Tensile force and proximal and distal construct deformation were measured at clinical failure, defined as 10 mm of displacement, and at ultimate failure, defined as failure of the reconstruction. Failure mechanism was recorded., Results: Tensile strength at time zero was higher in the allograft versus the turndown construct at clinical failure (156.9 ± 29.7 N versus 107.2 ± 20.0 N, respectively; mean difference, -49.7 N; 95% CI, -66.3 to -33.0 N; p < 0.001) and at ultimate failure (290.9 ± 83.2 N versus 140.7 ± 43.5 N, respectively; mean difference, -150.2 N; 95% CI, -202.9 to -97.6 N; p < 0.001). Distal construct deformation was lower in the turndown versus the allograft construct at clinical failure (1.6 ± 1.0 mm versus 4.7 ± 0.7 mm medially and 2.2 ± 1.0 mm versus 4.8 ± 1.1 mm laterally; p < 0.001). Semitendinosus allograft failure occurred via calcaneal bone bridge fracture in eight of nine specimens. All myofascial turndowns failed via suture pullout through the fascial tissue at its insertion., Conclusion: In this comparative biomechanical study, dual semitendinosus allograft reconstruction showed greater tensile strength and construct deformation compared with myofascial turndown in a cadaveric model of large Achilles tendon defects., Clinical Relevance: Further study of dual semitendinosus allograft for treatment of severe Achilles tendon defects with cyclic loading and investigation of clinical results will better elucidate the clinical utility and indications for this technique.

Purpose: When brachytherapy doses are reported or added, biologically effective dose (BED) minimum dose covering 90% of the volume (D90) is used as if dose is delivered uniformly to the target. Unlike BED(D90), equivalent uniform BED (EUBED) and generalized biologically equivalent uniform dose (gBEUD) are quantities that integrate dose inhomogeneity. Here we compared BED(D90) and equivalent uniform BED (EUBED)/gBEUD in 3 settings: (1) 2 sites using tandem and ovoid (T&O) but different styles of implants; (2) 2 sites using different devices-T&O and tandem and ring (T&R)-and different styles; and (3) the same site using T&O and T&R with the same style., Methods and Materials: EUBED and gBEUD were calculated for 260 fractions from 3 institutions using BED(α/β = 10 Gy). EUBED uses an extra parameter α with smaller values associated with radioresistant tumors. Similarly, gBEUD uses a, which places variable emphasis on hot/cold spots. Distributions were compared using the Kolmogorov-Smirnoff test at 5% significance., Results: For the 2 sites using T&O, the distribution of EUBED-BED(D90) was not different for values of α = 0.5 to 0.3 Gy -1 but was statistically different for values of α = 0.15 to 0.05 Gy -1 (P=.01, .002). The mean percentage differences between EUBED and BED(D90) ranged from 20% to 100% for α = 0.5 Gy -1 to 0.05 Gy -1 . Using gBEUD-BED(D90), the P values indicate the distributions to be similar for a = -10 but to be significantly different for other values of a (-5, -1, 1). Between sites and at the same site using T&O versus T&R, the distributions were statistically different with EUBED/gBEUD irrespective of parameter values at which these quantities were computed. These differences indicate that EUBED/gBEUD capture differences between the techniques and applicators that are not detected by the BED(D90)., Conclusions: BED(D90) is unable to distinguish between plans created by different devices or optimized differently. EUBED/gBEUD distinguish between dose distributions created by different devices and styles of implant and planning. This discrepancy is particularly important with the increased use of magnetic resonance imaging and hybrid devices, whereby one has the ability to create dose distributions that are significant departures from the classic pear., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The most common corrective surgery for adolescent idiopathic scoliosis (AIS) is posterior instrumented spinal fusion, which is a relatively lengthy procedure. Longer procedures are known to have higher rates of negative outcomes and higher economic costs across the surgical specialties. The purpose of this study is to identify the factors that influence the length of this operation in AIS patients. This was an institutional review board-approved, retrospective cohort study. All primary posterior instrumented arthrodesis procedures in 2011-2013 performed by three surgeons on AIS patients at a tertiary care hospital were included. Age, race, sex, BMI, Cobb angle, curve flexibility, Lenke classification, number of levels fused, number of screws used, osteotomy use, intraoperative O-arm use, and length of surgery (time from incision to closure) were obtained from the electronic medical record. Multivariable linear regression analysis was used to determine independent predictors of length of surgery, and standardized regression coefficients were calculated to compare the relative magnitude of significant variables. A total of 95 procedures were included. The average length of surgery was 375 ± 72.7 min. The multivariable linear regression analysis contained the variables Cobb angle, number of screws used, osteotomy use, Lenke curve type, surgeon, patient age, and sex. The regression identified the number of screws used [β=4.72, P=0.003, 95% confidence interval (CI) 1.7-7.8], osteotomy use (β = 50.2, P = 0.004, 95% CI 16.2-84.1), Lenke type 3 curve (β = 77.9, P = 0.001, 95% CI 31.7-174), male sex (β=62.5, P=0.003, 95% CI 21.5-103), the Cobb angle (β=1.04, P=0.045, 95% CI 0.02-2.1), and the surgeon (β = 75.2, P < 0.0001, 95% CI 40-110) as independently associated with the length of surgery. The most significant factor associated with operative duration was the surgeon performing the case. We identified male sex, number of screws used, Lenke type 3 curves, osteotomy use, Cobb angle, and the surgeon variable as significantly associated with increased length of surgery in posterior arthrodesis of AIS patients.

A 54-year-old male with history of anemia and rheumatoid arthritis presented with a three-month history of dyspnea on exertion and lower extremity edema. Patient was referred for a transthoracic echocardiogram that revealed a large right atrial mass with reduced ejection fraction of 40% and an incidental large liver mass. Subsequent cardiac MRI revealed a lobulated right atrial mass measuring 5.4 cm × 5.3 cm with inferior vena cava compression and adjacent multiple large liver lesions confirmed to be malignant melanoma through biopsy. Interestingly, no primaries were found in the patient. PET/CT imaging displayed hypermetabolic masses within the right atrium and liver that likely represent metastases, as well as bilateral pleural effusions, most likely due to heart failure. Preoperative coronary angiogram demonstrated perfusion to the mass by a dense network of neovasculature arising from the mid right coronary artery. The cardiac melanoma was surgically removed, and the right atrium was reconstructed with a pericardial patch. After surgery, all cardiac chambers appeared normal in size and function with associated moderate tricuspid regurgitation. The patient is currently being administered ipilimumab for systemic therapy of metastatic melanoma.

Described here is a unique case of Legionnaires' disease in a previously healthy 46 year old man in whom disseminated disease was demonstrated in the kidneys, bone marrow, spleen and multiple peripheral lymph nodes at autopsy. The pathologic distribution of the lesions suggests that dissemination occurred by both hematogenous and lymphatic pathways. Pancytopenia associated with bone marrow destruction and fibrosis suggests that substances toxic to hematopoietic cells were present. It is likely that many of the unusual systemic manifestations of this disease are related to dissemination of the bacterium. The findings presented extend the spectrum of the clinical and pathologic manifestations of Legionnaires' disease from a mild and self-limited illness to a severe and fatal disseminated form of the disease.