Convolutional Neural Network for Second Metacarpal Radiographic Osteoporosis Screening.

PURPOSE: Osteoporosis and osteopenia are extremely common and can lead to fragility fractures. The purpose of this study was to determine whether a computer learning system could classify whether a hand radiograph demonstrated osteoporosis based on the second metacarpal cortical percentage. METHODS: We used the second metacarpal cortical percentage as the osteoporosis predictor. A total of 4,000 posteroanterior (PA) radiographs of the hand were standardized through laterality correction, vertical alignment correction, segmentation, proxy osteoporosis predictor, and full pipeline. Laterality was classified using a LeNet convolutional neural network (CNN). Vertical alignment classification used 2,000 PA x-rays to determine vertical alignment of the second metacarpal. We employed segmentation to determine which pixels belong to the second metacarpal from 1,000 PA x-rays using the FSN-8 CNN. The full pipeline was tested on 265 previously unseen PA x-rays. RESULTS: Laterality classification accuracy was 99.62%, with a specificity of 100% and sensitivity of 99.3%. Rotation of the hand within 10° of vertical was accurate in 93.2% of films. Segmentation was 94.8% accurate. Proxy osteoporosis predictor was 88.4% accurate. Full pipeline accuracy was 93.9%. In the testing data set, the CNN had a sensitivity of 82.4% and specificity of 95.7%. In the balanced data set, 6 of 39 osteoporotic films were classified as nonosteoporotic; sensitivity was 82.4% and specificity, 94.3%. CONCLUSIONS: We have created a series of CNN that can accurately identify osteoporosis from non-osteoporosis. Furthermore, our CNN is able to make adjustments to images based on laterality and vertical alignment. CLINICAL RELEVANCE: Convolutional neural network and computer learning can be used as an adjunct to dual-energy x-ray absorptiometry scans or to screen and make appropriate referrals for further workup in patients with suspected osteoporosis.

The Impact of an Acute, Traumatic Wound Dehiscence on Clinical Outcomes Following Primary Knee Arthroplasty.

BACKGROUND: Early wound healing complications and persistent drainage are associated with an increased risk of infection following knee arthroplasty. However, the scenario in which a patient sustains an acute, traumatic wound dehiscence has not been investigated. The purpose of this study is to determine the outcomes of an acute traumatic wound dehiscence following arthroplasty treated with an urgent irrigation and debridement and primary wound closure. METHODS: Using a single institution's arthroplasty registry, patients sustaining an acute, traumatic wound dehiscence within 30 days of undergoing a primary knee arthroplasty were identified. Patients experiencing chronic wound drainage without injury or a history of prior infection were excluded. Patients were followed for the occurrence of complications and clinical outcomes using the Knee Society Score. RESULTS: From 2006 to 2016, 14 of 25,819 eligible patients (0.05%) were identified as having a traumatic wound dehiscence. The mean time from arthroplasty to wound dehiscence was 9.3 days. All but one patient was treated operatively within 24 hours of dehiscence. Postoperative antibiotics were administered for a mean of 21 days. At a mean of 6.5 years, 6 patients were considered failures (43%) including 2 deep infections, 3 revisions for instability, and 1 patient with a Knee Society Score <60 points. CONCLUSION: Despite emergent incision and drainage and wound closure, patients experiencing an acute traumatic wound dehiscence following knee arthroplasty subsequently exhibit high rates of reoperation for instability, periprosthetic infection, and clinical failure. Further work is required to better understand the optimal modes of treatment for this complication.

Biomechanical Effects of Subtalar Joint Fusion and Medial Ligament Reconstruction in Simulated Progressive Collapsing Foot Deformity.

BACKGROUND: The purpose of this study is to investigate the biomechanical effect of medial displacement calcaneal osteotomy (MDCO), subtalar joint fusion (SF), and medial ligament reconstruction (MLR: deltoid-spring ligament) in a severe flatfoot model. We hypothesized that (1) combination of MDCO and SF improves the tibiotalar and foot alignment in severe progressive collapsing foot deformity (PCFD) cadaver model. (2) However, if a residual valgus heel alignment remains after MCDO and SF, it can lead to increased medial ligament strain, foot malalignment, and tibiotalar valgus tilt, which will be mitigated by the addition of MLR. METHODS: Ten fresh-frozen cadaveric foot specimens were used to create a severe flatfoot model. The foot alignment changes, including the talo-first metatarsal angle in the axial and sagittal planes, subtalar angle, and tibiotalar angle in the coronal plane, were measured. The angles were measured at the initial condition, after creating the severe flatfoot model, and after each successive reconstructive procedure in the following order: (1) MDCO, (2) SF, and (3) MLR. RESULTS: Tibiotalar valgus tilt was decreased with the MDCO procedure: 4.4 vs 1.0 degrees (P = .04). Adding in situ SF to the MDCO led to increased tibiotalar tilt to 2.5 degrees was different from the initial condition (P = .01). Although the tibiotalar valgus tilt was significantly decreased after adding the MLR to the MDCO/SF procedure compared with the severe flatfoot model (0.8 vs 4.4 degrees, P = .03), no significant difference in the tibiotalar valgus tilt was observed between MDCO/SF and MDCO/SF with MLR. CONCLUSION: Our results demonstrated that MDCO significantly improved forefoot abduction and medial arch alignment, with no significant additional improvement observed with addition of SF. Following SF, a residual valgus heel alignment can contribute to subsequent tibiotalar valgus tilt. The addition of MLR did not show significantly decreased tibiotalar valgus tilt following SF. CLINICAL RELEVANCE: Residual valgus heel alignment after subtalar joint fusion in the surgical treatment of PCFD can lead to increased medial ligament strain. Although MLR might be considered for providing medial stability, it may not necessarily prevent the development of tibiotalar valgus tilt.

Combined Central Retinal Vein and Branch Retinal Artery Occlusion Post Intense Physical Activity.

We report a case of combined central retinal vein occlusion and branch retinal artery occlusion. A previously healthy 47-year-old male presented with decreased vision in the right eye after completing a half marathon. A fundus exam and retinal imaging revealed a combined central retinal vein and branch retinal artery occlusion. In the present report, we review the literature and discuss the possible mechanisms behind combined retinal vessel occlusions. To our knowledge, this is the first reported case of combined central retinal vein occlusion and branch retinal artery occlusion following intense exercise.

Upper Tract Urothelial Carcinoma in the Genetically Predisposed Patient: Role of Urinary Markers in Predicting Recurrence.

Background: Upper tract urothelial carcinoma (UTUC) is an uncommon disease that is diagnosed clinically by the selective use of urine cytology, urine biomarkers, and imaging of the upper tract. We present a case of a patient with Lynch syndrome and high-grade UTUC that was diagnosed by an abnormal Cxbladder assay, prompting further endoscopic examination. Case Presentation: A 59-year-old Caucasian female with a history of endometrial cancer and bladder cancer with Lynch syndrome presented for evaluation of recurrent urothelial carcinoma. Her previous bladder tumors have been T1 high grade and Ta high grade and have been treated with resection and multiple cycles of intravesical Bacillus Calmette-Guerin (BCG) therapy. She had also undergone a robotic left distal ureterectomy and psoas hitch for a high-grade distal ureteral tumor. Surveillance cystoscopy 7 months after revealed a biopsy-confirmed bladder tumor, which was resected, and she was started on maintenance BCG therapy. At presentation, follow-up urine cytology and UroVysion studies were negative. Cxbladder test was also initially negative. However, during close clinical monitoring, the Cxbladder test became positive. Cystoscopy was once more performed, which was unremarkable. Bilateral ureteroscopy was performed, revealing high-grade upper tract renal papillary carcinoma (UTUC) in the left renal pelvis. The patient declined a nephroureterectomy. She was treated with two sessions of holmium laser ablation of the left renal pelvis tumor and underwent 6 weekly courses of BCG + interferon instilled into her left renal pelvis using a 5F open-ended catheter. Repeat urine cytology, UroVysion, and Cxbladder tests were negative after completion of upper tract BCG therapy. Conclusion: Cxbladder test may be useful and an adjunct to urine cytology and the UroVysion FISH assay to evaluate patients at high risk for recurrent UTUC.