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143 result(s) for "Williams, Ariel A."
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Recurrent Shoulder Instability: Do Morbidity and Treatment Differ Based on Insurance?
Background: Patients with public insurance often face barriers to obtaining prompt orthopaedic care. For patients with recurrent traumatic anterior shoulder instability, delayed care may be associated with increasing bone loss and subsequently more extensive surgical procedures. Purpose/Hypothesis: The purpose of this study was to evaluate whether differences exist in patients undergoing treatment for shoulder instability between those with Medicaid versus non-Medicaid insurance. We hypothesized that at the time of surgery, Medicaid patients would have experienced greater delays in care, would have a more extensive history of instability, would have more bone loss, and would require more extensive surgical procedures than other patients. Study Design: Cohort study; Level of evidence, 3. Methods: Patients were identified who underwent surgical stabilization for traumatic anterior shoulder instability between January 1, 2011, and December 1, 2015, at a single sports medicine practice. Clinic, billing, and operative records were reviewed for each patient to determine age, sex, insurance type, total number of instability episodes, time from first instability episode to surgery, intraoperative findings, and procedure performed. Glenoid bone loss was quantified by use of preoperative imaging studies. Results: During this time period, 206 patients (55 Medicaid, 131 private insurance, 11 Tricare, 9 workers’ compensation) underwent surgical stabilization for traumatic anterior shoulder instability. Average wait time from initial injury to surgery was 1640 days (95% CI, 1155-2125 days) for Medicaid patients compared with 1237 days (95% CI, 834-1639 days) for others (P = .005). Medicaid patients were more likely to have sustained 5 or more instability events at the time of surgery (OR, 3.3; 95% CI, 1.64-6.69; P = .001), had a higher risk of having 15% or more glenoid bone loss on preoperative imaging (OR, 3.5; 95% CI, 1.3-10.0; P = .01), and had a higher risk of requiring Latarjet or other open stabilization procedures as opposed to an arthroscopic repair (OR, 3.0; 95% CI, 1.5-6.2; P = .002) when compared with other patients. Conclusion: Among patients undergoing surgery for traumatic anterior shoulder instability, patients with Medicaid had significantly more delayed care. Correspondingly, they reported a more extensive history of instability, were more likely to have severe bone loss, and required more invasive stabilization procedures.
Characterization of patellar maltracking using dynamic kinematic CT imaging in patients with patellar instability
Purpose Little has been reported on the relationship between patellar maltracking and instability. Patellar maltracking has been subjectively described with the “J sign” but is difficult to assess objectively using traditional imaging. Dynamic kinematic computed tomography (DKCT) allows dynamic assessment of the patellofemoral joint. DKCT was used to visualize and quantify patellar maltracking patterns, and severity of maltracking was correlated with the presence or absence of patellar instability symptoms. Methods Seventy-six knees in 38 patients were analysed using DKCT. Maltracking was defined as deviation of the patella from the trajectory of the trochlear groove and was characterized by patellar bisect offset, which was measured at 10° intervals of knee flexion during active flexion and extension. Bisect offset measurements were grouped by number of quadrants of maximum lateral patellar motion, with one, two, and three quadrants corresponding to 75–99, 100–125, and >125 %, respectively. Patellar instability symptoms were correlated with maltracking severity. Results Two knees were excluded because of poor imaging quality. Fifty of 74 knees had patellar instability, and 13 patients had bilateral symptoms. Of these, four (8 %) had normal tracking patterns; 41 (82 %) had increased lateral translation in extension, which we termed the J-sign pattern; 4 (8 %) had persistent lateralization of the patella throughout range of motion; and 1 had increased lateral translation in flexion. In knees with the J-sign pattern, degree of maltracking was graded by severity: J1 ( n  = 24), J2 ( n  = 19), and J3 ( n  = 15). The sensitivities of J-sign grades in predicting patellar instability symptoms were 50 % (J1), 80 % (J2), and 93 % (J3) ( p  < 0.01). There were significant differences in sensitivity between knees with no J sign or J1 versus J2 or J3 ( p  = 0.02). Conclusion DKCT showed several patellar maltracking patterns in patients with patellar instability. A J-sign pattern with more than two quadrants of lateral translation correlated with the presence of patellar instability symptoms. Incorporation of this approach of objectively quantifying maltracking patterns is recommended in the evaluation of patellofemoral instability. Level of evidence IV.
Calcific Tendinitis of the Gluteus Maximus in a Golfer
Calcific tendinitis is a relatively rare condition in which calcium is inappropriately deposited in tendons, resulting in a local inflammatory reaction that can cause severe symptoms in certain cases. The cause of this disease process is not completely understood, although repetitive microtrauma likely plays a role in its development. Although the disorder most often involves the rotator cuff, it can affect other structures throughout the body, such as the tendons about the ankle and hip—including the rectus femoris and gluteus maximus. Nonoperative management typically involves using an anti-inflammatory medication and activity modification and can be augmented with formal physical therapy and modalities. Although nonoperative management provides adequate relief for many patients, sometimes operative debridement of the calcific deposit with or without repair of the involved tendon is required. The authors report an unusual case of calcific tendinitis of the gluteus maximus insertion in a golfer. The patient had tried nonoperative treatment for approximately 2 years with no real relief, and a recent exacerbation of the pain was significantly delaying his return to sport. Although plain radiographs did not show abnormalities, magnetic resonance imaging showed a calcific deposit in the insertion of the gluteus maximus tendon. After discussing further treatment options with the patient, the decision was made to remove the deposit and repair the insertion. He recovered completely and was able to return to play. The frequency, pathogenesis, and treatment of this condition are discussed in this case report, as well as the possible link to golf in this patient. [ Orthopedics. 2016; 39(5):e997–e1000.]
Pediatric hand and wrist injuries
In the last 40 years, childhood hand and wrist injuries have become progressively more common as children have become heavier and more active in high impact sports. The majority of children with such injuries do well, but treatment is not always straightforward. Distal radius fractures, scaphoid fractures, metacarpal and phalangeal fractures, nailbed injuries, and amputations are among the pediatric hand and wrist injuries most often seen by orthopedists. These are all discussed, with a focus on the most recent literature and areas of evolving controversy.
CD 9 and vimentin distinguish clear cell from chromophobe renal cell carcinoma
Background Clear cell renal cell carcinoma (ccRCC) and chromophobe renal cell carcinoma (chRCC) can usually be distinguished by histologic characteristics. Occasionally, diagnosis proves challenging and diagnostic difficulty will likely increase as needle biopsies of renal lesions become more common. Methods To identify markers that aid in differentiating ccRCC from chRCC, we used gene expression profiles to identify candidate markers that correlate with histology. 39 antisera and antibodies, including 35 for transcripts identified from gene expression profiling, were evaluated. Promising markers were tested on a tissue microarray (TMA) containing 428 renal neoplasms. Strength of staining of each core on the TMA was formally scored and the distribution of staining across different types of renal neoplasms was analyzed. Results Based on results from initial immunohistochemical staining of multitissue titer arrays, 23 of the antisera and antibodies were selected for staining of the TMA. For 7 of these markers, strength of staining of each core on the TMA was formally scored. Vimentin (positive in ccRCC) and CD9 (positive in chRCC) best distinguished ccRCC from chRCC. The combination of vimentin negativity and CD9 positivity was found to distinguish chRCC from ccRCC with a sensitivity of 100.0% and a specificity of 95.2%. Conclusion Based on gene expression analysis, we identify CD9 and vimentin as candidate markers for distinguishing between ccRCC and chRCC. In difficult cases and particularly when the amount of diagnostic tissue is limited, vimentin and CD9 staining could serve as a useful adjunct in the differential diagnosis of ccRCC and chRCC.
Repair Integrity and Clinical Outcomes Following Arthroscopic Rotator Cuff Repair
Objectives:To prospectively evaluate the effect of early versus delayed motion on repair integrity on 6-month postoperative magnetic resonance imaging (MRI) scans following rotator cuff repair, and to correlate repair integrity with clinical and functional outcomes. We hypothesized that repair integrity would differ between the early and delayed groups and that patients with repair failures would have worse clinical and functional outcomes.Methods:This was a prospective, randomized, single blinded clinical trial comparing an early motion (post-op day 2-3) to a delayed motion (post-op day 28) rehabilitation protocol following arthroscopic repair of isolated supraspinatus tears. All patients underwent MRI at 6 months post-operatively as part of the study protocol. A blinded board-certified and fellowship-trained orthopaedic surgeon (not part of the surgical team) reviewed operative photos and video to confirm the presence of a full thickness supraspinatus tear and to ensure an adequate and consistent repair. The same surgeon along with a blinded sports medicine fellowship-trained musculoskeletal radiologist independently reviewed all MRIs to determine whether the repair was intact at 6 months. Outcome measures were collected by independent evaluators who were also blinded to group assignment. These included the Western Ontario Rotator Cuff (WORC) index, Single Assessment Numeric Evaluation (SANE) ratings, pain scores, sling use, and physical exam data. Enrolled patients were followed at 6 weeks, 6 months, and 1 year.Results:From October 2008 to April 2012, 73 patients met all inclusion criteria and were willing to participate. 36 patients were randomized to delayed motion and 37 were randomized to early motion. The final study group at 6 months consisted of 58 study participants. Postoperative MRIs were obtained on all of these patients at 6 months regardless of whether or not they were progressing as expected. These MRIs demonstrated an overall failure rate of 29%. This did not differ significantly based on early or late motion, with 9 (26%) tears occurring in the delayed motion group compared to 10 (32%) in the early motion group (p=0.70). When patients with repair failures were compared to those with intact cuffs, no significant differences were detected in range of motion, strength, or WORC, SANE, or pain scores at 6 months or 1 year. Interestingly, however, at 6 weeks, both WORC and SANE scores were significantly better in patients who were later found to have repair failures on MRI (p<0.05). When evaluated irrespective of rehabilitation protocol, non-compliance with sling use was associated with higher failures rates (p<0.05).Conclusion:Repair failure rates do not significantly differ between patients randomized to early and delayed motion protocols following arthroscopic single tendon rotator cuff repair. Repair failure on MRI does not correlate with clinical outcome at 6 months or 1 year. However, better subjective outcome scores at 6 weeks are associated with higher rates of repair failure at 6 months.
Repair Integrity and Clinical Outcomes Following Arthroscopic Rotator Cuff Repair
Objectives: To prospectively evaluate the effect of early versus delayed motion on repair integrity on 6-month postoperative magnetic resonance imaging (MRI) scans following rotator cuff repair, and to correlate repair integrity with clinical and functional outcomes. We hypothesized that repair integrity would differ between the early and delayed groups and that patients with repair failures would have worse clinical and functional outcomes. Methods: This was a prospective, randomized, single blinded clinical trial comparing an early motion (post-op day 2-3) to a delayed motion (post-op day 28) rehabilitation protocol following arthroscopic repair of isolated supraspinatus tears. All patients underwent MRI at 6 months post-operatively as part of the study protocol. A blinded board-certified and fellowship-trained orthopaedic surgeon (not part of the surgical team) reviewed operative photos and video to confirm the presence of a full thickness supraspinatus tear and to ensure an adequate and consistent repair. The same surgeon along with a blinded sports medicine fellowship-trained musculoskeletal radiologist independently reviewed all MRIs to determine whether the repair was intact at 6 months. Outcome measures were collected by independent evaluators who were also blinded to group assignment. These included the Western Ontario Rotator Cuff (WORC) index, Single Assessment Numeric Evaluation (SANE) ratings, pain scores, sling use, and physical exam data. Enrolled patients were followed at 6 weeks, 6 months, and 1 year. Results: From October 2008 to April 2012, 73 patients met all inclusion criteria and were willing to participate. 36 patients were randomized to delayed motion and 37 were randomized to early motion. The final study group at 6 months consisted of 58 study participants. Postoperative MRIs were obtained on all of these patients at 6 months regardless of whether or not they were progressing as expected. These MRIs demonstrated an overall failure rate of 29%. This did not differ significantly based on early or late motion, with 9 (26%) tears occurring in the delayed motion group compared to 10 (32%) in the early motion group (p=0.70). When patients with repair failures were compared to those with intact cuffs, no significant differences were detected in range of motion, strength, or WORC, SANE, or pain scores at 6 months or 1 year. Interestingly, however, at 6 weeks, both WORC and SANE scores were significantly better in patients who were later found to have repair failures on MRI (p<0.05). When evaluated irrespective of rehabilitation protocol, non-compliance with sling use was associated with higher failures rates (p<0.05). Conclusion: Repair failure rates do not significantly differ between patients randomized to early and delayed motion protocols following arthroscopic single tendon rotator cuff repair. Repair failure on MRI does not correlate with clinical outcome at 6 months or 1 year. However, better subjective outcome scores at 6 weeks are associated with higher rates of repair failure at 6 months.
CD9 and vimentin distinguish clear cell from chormophobe renal cell carcinoma
Background: Clear cell renal cell carcinoma (ccRCC) and chromophobe renal cell carcinoma(chRCC) can usually be distinguished by histologic characteristics. Occasionally, diagnosis proveschallenging and diagnostic difficulty will likely increase as needle biopsies of renal lesions becomemore common.Methods: To identify markers that aid in differentiating ccRCC from chRCC, we used geneexpression profiles to identify candidate markers that correlate with histology. 39 antisera andantibodies, including 35 for transcripts identified from gene expression profiling, were evaluated.Promising markers were tested on a tissue microarray (TMA) containing 428 renal neoplasms.Strength of staining of each core on the TMA was formally scored and the distribution of stainingacross different types of renal neoplasms was analyzed.Results: Based on results from initial immunohistochemical staining of multitissue titer arrays, 23of the antisera and antibodies were selected for staining of the TMA. For 7 of these markers,strength of staining of each core on the TMA was formally scored. Vimentin (positive in ccRCC)and CD9 (positive in chRCC) best distinguished ccRCC from chRCC. The combination of vimentinnegativity and CD9 positivity was found to distinguish chRCC from ccRCC with a sensitivity of100.0% and a specificity of 95.2%.Conclusion: Based on gene expression analysis, we identify CD9 and vimentin as candidatemarkers for distinguishing between ccRCC and chRCC. In difficult cases and particularly when theamount of diagnostic tissue is limited, vimentin and CD9 staining could serve as a useful adjunct inthe differential diagnosis of ccRCC and chRCC.
A single N6-methyladenosine site regulates lncRNA HOTAIR function in breast cancer cells
N6-methyladenosine (m6A) modification of RNA regulates normal and cancer biology, but knowledge of its function on long noncoding RNAs (lncRNAs) remains limited. Here, we reveal that m6A regulates the breast cancer-associated human lncRNA HOTAIR. Mapping m6A in breast cancer cell lines, we identify multiple m6A sites on HOTAIR, with 1 single consistently methylated site (A783) that is critical for HOTAIR-driven proliferation and invasion of triple-negative breast cancer (TNBC) cells. Methylated A783 interacts with the m6A “reader” YTHDC1, promoting chromatin association of HOTAIR, proliferation and invasion of TNBC cells, and gene repression. A783U mutant HOTAIR induces a unique antitumor gene expression profile and displays loss-of-function and antimorph behaviors by impairing and, in some cases, causing opposite gene expression changes induced by wild-type (WT) HOTAIR. Our work demonstrates how modification of 1 base in an lncRNA can elicit a distinct gene regulation mechanism and drive cancer-associated phenotypes.
ZATT (ZNF451)–mediated resolution of topoisomerase 2 DNA-protein cross-links
Topoisomerase 2 (TOP2) DNA transactions proceed via formation of the TOP2 cleavage complex (TOP2cc), a covalent enzyme-DNA reaction intermediate that is vulnerable to trapping by potent anticancer TOP2 drugs. How genotoxic TOP2 DNA-protein cross-links are resolved is unclear. We found that the SUMO (small ubiquitin-related modifier) ligase ZATT (ZNF451) is a multifunctional DNA repair factor that controls cellular responses to TOP2 damage. ZATT binding to TOP2cc facilitates a proteasome-independent tyrosyl-DNA phosphodiesterase 2 (TDP2) hydrolase activity on stalled TOP2cc. The ZATT SUMO ligase activity further promotes TDP2 interactions with SUMOylated TOP2, regulating efficient TDP2 recruitment through a “split-SIM” SUMO2 engagement platform. These findings uncover a ZATT-TDP2–catalyzed and SUMO2-modulated pathway for direct resolution of TOP2cc.