Samuel K. Nwosu
Vanderbilt University
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American Journal of Sports Medicine | 2014
Charles L. Cox; Laura J. Huston; Warren R. Dunn; Emily K. Reinke; Samuel K. Nwosu; Richard D. Parker; Rick W. Wright; Christopher C. Kaeding; Robert G. Marx; Annunziata Amendola; Eric C. McCarty; Kurt P. Spindler
Background: Identifying risk factors for inferior outcomes after anterior cruciate ligament reconstruction (ACLR) is important for prognosis and future treatment. Hypothesis: Articular cartilage lesions and meniscus tears/treatment would predict International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS) (all 5 subscales), and Marx activity level at 6 years after ACLR. Study Design: Cohort study (prognosis); Level of evidence, 1. Methods: Between 2002 and 2004, a total of 1512 ACLR patients were prospectively enrolled and followed longitudinally, with the IKDC, KOOS, and Marx activity score completed at entry, 2 years, and 6 years. A logistic regression model was built incorporating variables from patient demographics, surgical technique, articular cartilage injuries, and meniscus tears/treatment to determine the predictors (risk factors) of IKDC and KOOS scores and Marx activity level at 6 years. Results: A minimum follow-up on 86% (1307/1512) of the cohort was completed at 6 years. The cohort was 56% male and had a median age of 23 years at the time of enrollment, with 76% reporting a noncontact injury mechanism. Incidence of concomitant injury at the time of surgery consisted of the following: articular cartilage (medial femoral condyle [MFC], 25%; lateral femoral condyle [LFC] 20%; medial tibial plateau [MTP], 6%; lateral tibial plateau [LTP], 12%; patella, 20%; trochlear, 9%) and meniscus (medial, 38%; lateral, 46%). Both articular cartilage lesions and meniscus tears were significant predictors of 6-year outcomes on the IKDC and KOOS. Grade 3 or 4 articular cartilage lesions (excluding patella) significantly reduced IKDC and KOOS scores at 6 years. The IKDC demonstrated worse outcomes with the presence of a grade 3 or 4 chondral lesion on the MFC, MTP, and LFC. Likewise, the KOOS score was negatively affected by cartilage injury. The sole significant predictor of reduced Marx activity level was the presence of a grade 4 lesion on the MFC. Lateral meniscus repairs did not correlate with inferior results, but medial meniscus repairs predicted worse IKDC and KOOS scores. Lateral meniscus tears left alone significantly improved prognosis. Small partial meniscectomies (<33%) on the medial meniscus fared worse; conversely, larger excisions (>50%) on either the medial or lateral menisci improved prognosis. Analogous to previous studies, other significant predictors of lower outcome scores were lower baseline scores, higher body mass index, lower education level, smoking, and anterior cruciate ligament revisions. Conclusion: Both articular cartilage injury and meniscus tears/treatment at the time of ACLR were significant predictors of IKDC and KOOS scores 6 years after ACLR. Similarly, having a grade 4 MFC lesion significantly reduced a patient’s Marx activity level score at 6 years.
American Journal of Sports Medicine | 2014
Charles L. Cox; Laura J. Huston; Warren R. Dunn; Emily K. Reinke; Samuel K. Nwosu; Richard D. Parker; Rick W. Wright; Christopher C. Kaeding; Robert G. Marx; Annunziata Amendola; Eric C. McCarty; Kurt P. Spindler; Brian R. Wolf; Frank E. Harrell
Background: Identifying risk factors for inferior outcomes after anterior cruciate ligament reconstruction (ACLR) is important for prognosis and future treatment. Hypothesis: Articular cartilage lesions and meniscus tears/treatment would predict International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS) (all 5 subscales), and Marx activity level at 6 years after ACLR. Study Design: Cohort study (prognosis); Level of evidence, 1. Methods: Between 2002 and 2004, a total of 1512 ACLR patients were prospectively enrolled and followed longitudinally, with the IKDC, KOOS, and Marx activity score completed at entry, 2 years, and 6 years. A logistic regression model was built incorporating variables from patient demographics, surgical technique, articular cartilage injuries, and meniscus tears/treatment to determine the predictors (risk factors) of IKDC and KOOS scores and Marx activity level at 6 years. Results: A minimum follow-up on 86% (1307/1512) of the cohort was completed at 6 years. The cohort was 56% male and had a median age of 23 years at the time of enrollment, with 76% reporting a noncontact injury mechanism. Incidence of concomitant injury at the time of surgery consisted of the following: articular cartilage (medial femoral condyle [MFC], 25%; lateral femoral condyle [LFC] 20%; medial tibial plateau [MTP], 6%; lateral tibial plateau [LTP], 12%; patella, 20%; trochlear, 9%) and meniscus (medial, 38%; lateral, 46%). Both articular cartilage lesions and meniscus tears were significant predictors of 6-year outcomes on the IKDC and KOOS. Grade 3 or 4 articular cartilage lesions (excluding patella) significantly reduced IKDC and KOOS scores at 6 years. The IKDC demonstrated worse outcomes with the presence of a grade 3 or 4 chondral lesion on the MFC, MTP, and LFC. Likewise, the KOOS score was negatively affected by cartilage injury. The sole significant predictor of reduced Marx activity level was the presence of a grade 4 lesion on the MFC. Lateral meniscus repairs did not correlate with inferior results, but medial meniscus repairs predicted worse IKDC and KOOS scores. Lateral meniscus tears left alone significantly improved prognosis. Small partial meniscectomies (<33%) on the medial meniscus fared worse; conversely, larger excisions (>50%) on either the medial or lateral menisci improved prognosis. Analogous to previous studies, other significant predictors of lower outcome scores were lower baseline scores, higher body mass index, lower education level, smoking, and anterior cruciate ligament revisions. Conclusion: Both articular cartilage injury and meniscus tears/treatment at the time of ACLR were significant predictors of IKDC and KOOS scores 6 years after ACLR. Similarly, having a grade 4 MFC lesion significantly reduced a patient’s Marx activity level score at 6 years.
American Journal of Sports Medicine | 2014
Rick W. Wright; Laura J. Huston; Amanda K. Haas; Kurt P. Spindler; Samuel K. Nwosu; Christina R. Allen; Allen F. Anderson; Daniel E. Cooper; Thomas M. DeBerardino; Warren R. Dunn; Brett A. Lantz; Michael J. Stuart; Elizabeth A. Garofoli; John P. Albright; Annunziato Amendola; Jack T. Andrish; Christopher C. Annunziata; Robert A. Arciero; Bernard R. Bach; Champ L. Baker; Arthur R. Bartolozzi; Keith M. Baumgarten; Jeffery R. Bechler; Jeffrey H. Berg; Geoffrey A. Bernas; Stephen F. Brockmeier; Robert H. Brophy; J. Brad Butler; John D. Campbell; James L. Carey
Background: Most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome; however, graft choice for revision may be limited due to previously used grafts. Hypotheses: Autograft use would result in increased sports function, increased activity level, and decreased osteoarthritis symptoms (as measured by validated patient-reported outcome instruments). Autograft use would result in decreased graft failure and reoperation rate 2 years after revision ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Patients undergoing revision ACL reconstruction were identified and prospectively enrolled by 83 surgeons at 52 sites. Data collected included baseline demographics, surgical technique, pathologic abnormalities, and the results of a series of validated, patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], and Marx activity rating score). Patients were followed up at 2 years and asked to complete the identical set of outcome instruments. Incidences of additional surgery and reoperation due to graft failure were also recorded. Multivariate regression models were used to determine the predictors (risk factors) of IKDC, KOOS, WOMAC, Marx scores, graft rerupture, and reoperation rate at 2 years after revision surgery. Results: A total of 1205 patients (697 [58%] males) were enrolled. The median age was 26 years. In 88% of patients, this was their first revision, and 341 patients (28%) were undergoing revision by the surgeon who had performed the previous reconstruction. The median time since last ACL reconstruction was 3.4 years. Revision using an autograft was performed in 583 patients (48%), allograft was used in 590 (49%), and both types were used in 32 (3%). Questionnaire follow-up was obtained for 989 subjects (82%), while telephone follow-up was obtained for 1112 (92%). The IKDC, KOOS, and WOMAC scores (with the exception of the WOMAC stiffness subscale) all significantly improved at 2-year follow-up (P < .001). In contrast, the 2-year Marx activity score demonstrated a significant decrease from the initial score at enrollment (P < .001). Graft choice proved to be a significant predictor of 2-year IKDC scores (P = .017). Specifically, the use of an autograft for revision reconstruction predicted improved score on the IKDC (P = .045; odds ratio [OR] = 1.31; 95% CI, 1.01-1.70). The use of an autograft predicted an improved score on the KOOS sports and recreation subscale (P = .037; OR = 1.33; 95% CI, 1.02-1.73). Use of an autograft also predicted improved scores on the KOOS quality of life subscale (P = .031; OR = 1.33; 95% CI, 1.03-1.73). For the KOOS symptoms and KOOS activities of daily living subscales, graft choice did not predict outcome score. Graft choice was a significant predictor of 2-year Marx activity level scores (P = .012). Graft rerupture was reported in 37 of 1112 patients (3.3%) by their 2-year follow-up: 24 allografts, 12 autografts, and 1 allograft and autograft. Use of an autograft for revision resulted in patients being 2.78 times less likely to sustain a subsequent graft rupture compared with allograft (P = .047; 95% CI, 1.01-7.69). Conclusion: Improved sports function and patient-reported outcome measures are obtained when an autograft is used. Additionally, use of an autograft shows a decreased risk in graft rerupture at 2-year follow-up. No differences were noted in rerupture or patient-reported outcomes between soft tissue and bone–patellar tendon–bone grafts. Surgeon education regarding the findings of this study has the potential to improve the results of revision ACL reconstruction.
Quality & Safety in Health Care | 2010
Theodore Speroff; Samuel K. Nwosu; Robert A. Greevy; Matthew B. Weinger; Thomas R. Talbot; Richard J Wall; Jayant K. Deshpande; E W Ely; Hayley Burgess; Jane Englebright; Mark V. Williams; Robert S. Dittus
Context Bureaucratic organisational culture is less favourable to quality improvement, whereas organisations with group (teamwork) culture are better aligned for quality improvement. Objective To determine if an organisational group culture shows better alignment with patient safety climate. Design Cross-sectional administration of questionnaires. Setting 40 Hospital Corporation of America hospitals. Participants 1406 nurses, ancillary staff, allied staff and physicians. Main outcome measures Competing Values Measure of Organisational Culture, Safety Attitudes Questionnaire (SAQ), Safety Climate Survey (SCSc) and Information and Analysis (IA). Results The Cronbach alpha was 0.81 for the group culture scale and 0.72 for the hierarchical culture scale. Group culture was positively correlated with SAQ and its subscales (from correlation coefficient r=0.44 to 0.55, except situational recognition), ScSc (r=0.47) and IA (r=0.33). Hierarchical culture was negatively correlated with the SAQ scales, SCSc and IA. Among the 40 hospitals, 37.5% had a hierarchical dominant culture, 37.5% a dominant group culture and 25% a balanced culture. Group culture hospitals had significantly higher safety climate scores than hierarchical culture hospitals. The magnitude of these relationships was not affected after adjusting for provider job type and hospital characteristics. Conclusions Hospitals vary in organisational culture, and the type of culture relates to the safety climate within the hospital. In combination with prior studies, these results suggest that a healthcare organisations culture is a critical factor in the development of its patient safety climate and in the successful implementation of quality improvement initiatives.
Journal of Bone and Joint Surgery, American Volume | 2015
Robert H. Brophy; Rick W. Wright; Laura J. Huston; Samuel K. Nwosu; Kurt P. Spindler
BACKGROUND Although rare, infection can be devastating after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to test the association between infection after ACL reconstruction and potential risk factors such as age, body mass index (BMI), smoking, diabetes, and graft choice. METHODS We reviewed the Multicenter Orthopaedic Outcomes Network (MOON) cohort from 2002 to 2005 to identify patients with a postoperative infection. The age, BMI, smoking status, history of diabetes, and graft choice were recorded for each patient. A multivariable regression analysis was constructed to examine which baseline risk factors were independently associated with postoperative infection after ACL reconstruction requiring surgical intervention. RESULTS There were 2198 eligible patients in the cohort, with seventeen (0.8%) reporting a postoperative infection. Diabetes was found to be a significant risk factor for infection (odds ratio [OR] = 18.8; 95% confidence interval [CI] = 3.8 to 94.0; p < 0.001). Compared with bone-tendon-bone autograft, both hamstring autograft and other grafts (e.g., the majority of allografts, with some that were both autograft and allograft) also increased the risk of infection (OR = 4.6 [95% CI = 1.2 to 17.9; p = 0.026] for hamstrings and 4.3 [95% CI = 1.0 to 18.1; p = 0.047] for other grafts). Although the OR for infection in smokers was 2.5, this finding did not reach significance. CONCLUSIONS Patients with diabetes undergoing ACL reconstruction have a significantly elevated risk of postoperative infection (18.8-times higher odds) compared with that for patients without diabetes. Use of bone-tendon-bone autograft is associated with a lower risk of infection after ACL reconstruction.
Mayo Clinic Proceedings | 2014
Amanda S. Mixon; Amy P. Myers; Cardella Leak; J. Mary Lou Jacobsen; Courtney Cawthon; Kathryn Goggins; Samuel K. Nwosu; Jonathan S. Schildcrout; John F. Schnelle; Theodore Speroff; Sunil Kripalani
OBJECTIVE To examine the association of patient- and medication-related factors with postdischarge medication errors. PATIENTS AND METHODS The Vanderbilt Inpatient Cohort Study includes adults hospitalized with acute coronary syndromes and/or acute decompensated heart failure. We measured health literacy, subjective numeracy, marital status, cognition, social support, educational attainment, income, depression, global health status, and medication adherence in patients enrolled from October 1, 2011, through August 31, 2012. We used binomial logistic regression to determine predictors of discordance between the discharge medication list and the patient-reported list during postdischarge medication review. RESULTS Among 471 patients (mean age, 59 years), the mean total number of medications reported was 12, and 79 patients (16.8%) had inadequate or marginal health literacy. A total of 242 patients (51.4%) were taking 1 or more discordant medication (ie, appeared on either the discharge list or patient-reported list but not both), 129 (27.4%) failed to report a medication on their discharge list, and 168 (35.7%) reported a medication not on their discharge list. In addition, 279 participants (59.2%) had a misunderstanding in indication, dose, or frequency in a cardiac medication. In multivariable analyses, higher subjective numeracy (odds ratio [OR], 0.81; 95% CI, 0.67-0.98) was associated with lower odds of having discordant medications. For cardiac medications, participants with higher health literacy (OR, 0.84; 95% CI, 0.74-0.95), with higher subjective numeracy (OR, 0.77; 95% CI, 0.63-0.95), and who were female (OR, 0.60; 95% CI, 0.46-0.78) had lower odds of misunderstandings in indication, dose, or frequency. CONCLUSION Medication errors are present in approximately half of patients after hospital discharge and are more common among patients with lower numeracy or health literacy.
American Journal of Sports Medicine | 2016
Rick W. Wright; Laura J. Huston; Samuel K. Nwosu; Amanda K. Haas; Christina R. Allen; Allen F. Anderson; Daniel E. Cooper; Thomas M. DeBerardino; Warren R. Dunn; Brett A. Lantz; Barton J. Mann; Kurt P. Spindler; Michael J. Stuart; John P. Albright; Annunziato Amendola; Jack T. Andrish; Christopher C. Annunziata; Robert A. Arciero; Bernard R. Bach; Champ L. Baker; Arthur R. Bartolozzi; Keith M. Baumgarten; Jeffery R. Bechler; Jeffrey H. Berg; Geoffrey A. Bernas; Stephen F. Brockmeier; Robert H. Brophy; J. Brad Butler; John D. Campbell; James L. Carey
Background: Revision anterior cruciate ligament (ACL) reconstruction has been documented to have worse outcomes compared with primary ACL reconstructions. Purpose/Hypothesis: The purpose of this study was to determine if the prevalence, location, and/or degree of meniscal and chondral damage noted at the time of revision ACL reconstruction predicts activity level, sports function, and osteoarthritis symptoms at 2-year follow-up. The hypothesis was that meniscal loss and high-grade chondral damage noted at the time of revision ACL reconstruction will result in lower activity levels, decreased sports participation, more pain, more stiffness, and more functional limitation at 2 years after revision surgery. Study Design: Cohort study; Level of evidence, 2. Methods: Between 2006 and 2011, a total of 1205 patients who underwent revision ACL reconstruction by 83 surgeons at 52 hospitals were accumulated for study of the relationship of meniscal and articular cartilage damage to outcome. Baseline demographic and intraoperative data, including the International Knee Documentation Committee (IKDC) subjective knee evaluation, Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx activity score, were collected initially and at 2-year follow-up to test the hypothesis. Regression analysis was used to control for age, sex, body mass index, smoking status, activity level, baseline outcome scores, revision number, time since last ACL reconstruction, incidence of having a previous ACL reconstruction on the contralateral knee, previous and current meniscal and articular cartilage injury, graft choice, and surgeon years of experience to assess the meniscal and articular cartilage risk factors for clinical outcomes 2 years after revision ACL reconstruction. Results: At 2-year follow-up, 82% (989/1205) of the patients returned their questionnaires. It was found that previous meniscal injury and current articular cartilage damage were associated with the poorest outcomes, with prior lateral meniscectomy and current grade 3 to 4 trochlear articular cartilage changes having the worst outcome scores. Activity levels at 2 years were not affected by meniscal or articular cartilage pathologic changes. Conclusion: Prior lateral meniscectomy and current grade 3 to 4 changes of the trochlea were associated with worse outcomes in terms of decreased sports participation, more pain, more stiffness, and more functional limitation at 2 years after revision surgery, but they had no effect on activity levels. Registration: NCT00625885
American Journal of Sports Medicine | 2015
Robert H. Brophy; Amanda K. Haas; Laura J. Huston; Samuel K. Nwosu; Rick W. Wright
Background: Knees undergoing revision anterior cruciate ligament reconstruction (rACLR) have a high prevalence of articular cartilage lesions. Hypothesis: The prevalence of chondrosis at the time of rACLR is associated with meniscal status and lower extremity alignment. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Data from the prospective Multicenter ACL Revision Study (MARS) cohort were reviewed to identify patients with preoperative lower extremity alignment films. Lower extremity alignment was defined by the weightbearing line (WBL) as a percentage of the tibial plateau width, while the chondral and meniscal status of each weightbearing compartment was recorded at the time of surgery. Multivariable proportional odds models were constructed and adjusted for relevant factors to examine which risk factors were independently associated with the degree of medial and lateral compartment chondrosis. Results: The cohort included 246 patients with lower extremity alignment films at the time of rACLR. Mean (±SD) patient age was 26.9 ± 9.5 years and body mass index (BMI) was 26.4 ± 4.6. The medial compartment had more chondrosis (grade 2/3, 42%; grade 4, 6.5%) than did the lateral compartment (grade 2/3, 26%; grade 4, 6.5%). Disruption of the meniscus was noted in 35% of patients on the medial side and 16% in the lateral side. The mean WBL was 0.43 ± 0.13. Medial compartment chondrosis was associated with BMI (P = .025), alignment (P = .002), and medial meniscal status (P = .001). None of the knees with the WBL lateral to 0.625 had grade 4 chondrosis in the medial compartment. Lateral compartment chondrosis was significantly associated with age (P = .013) and lateral meniscal status (P < .001). Subjects with “intact” menisci were found to decrease their odds of having chondrosis by 64% to 84%. Conclusion: The status of articular cartilage in the tibiofemoral compartments at the time of rACLR is related to meniscal status. Lower extremity alignment and BMI are associated with medial compartment chondrosis.
Journal of Health Communication | 2015
Sunil Kripalani; Kathryn Goggins; Samuel K. Nwosu; Jonathan S. Schildcrout; Amanda S. Mixon; Candace D. McNaughton; Amanda M McDougald Scott; Kenneth A. Wallston
Medication nonadherence increases the risk of hospitalization and poor outcomes, particularly among patients with cardiovascular disease. The purpose of this study was to examine characteristics associated with medication nonadherence among adults hospitalized for cardiovascular disease. Patients in the Vanderbilt Inpatient Cohort Study who were admitted for acute coronary syndrome or heart failure completed validated assessments of self-reported medication adherence (the Adherence to Refills and Medications Scale), demographic characteristics, health literacy, numeracy, social support, depressive symptoms, and health competence. We modeled the independent predictors of nonadherence before hospitalization, standardizing estimated effects by each predictors interquartile range. Among 1,967 patients studied, 70.7% indicated at least some degree of medication nonadherence leading up to their hospitalization. Adherence was significantly lower among patients with lower health literacy (0.18-point change in adherence score per interquartile range change in health literacy), lower numeracy (0.28), lower health competence (0.30), and more depressive symptoms (0.52) and those of younger age, of non-White race, of male gender, or with less social support. Medication nonadherence in the period before hospitalization is more prevalent among patients with lower health literacy, numeracy, or other intervenable psychosocial factors. Addressing these factors in a coordinated care model may reduce hospitalization rates.
Osteoarthritis and Cartilage | 2015
D. Wasserstein; Laura J. Huston; Samuel K. Nwosu; Christopher C. Kaeding; Richard D. Parker; Rick W. Wright; Jack T. Andrish; Robert G. Marx; Annunziato Amendola; Brian R. Wolf; Eric C. McCarty; Michelle L. Wolcott; Warren R. Dunn; Kurt P. Spindler
OBJECTIVE The prevalence of radiographic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR) approaches 50%, yet the prevalence of significant knee pain is unknown. We applied three different models of Knee injury and Osteoarthritis Outcome Score (KOOS) thresholds for significant knee pain to an ACLR cohort to identify prevalence and risk factors. DESIGN Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort patients with a unilateral primary ACLR and normal contralateral knee were assessed at 2 and 6 years. Independent variables included patient demographics, validated Patient Reported Outcomes (PRO; Marx activity score, KOOS), and surgical characteristics. Models included: (1) KOOS criteria for a painful knee = quality of life subscale <87.5 and ≥2 of: KOOSpain <86.1, KOOSsymptoms <85.7, KOOSADL <86.8, or KOOSsports/rec <85.0; (2) KOOSpain subscale score ≤72 (≥2 standard deviations below population mean); (3) 10-point KOOSpain drop from 2 to 6 years. Proportional odds models (alpha ≤ 0.05) were used. RESULTS 1761 patients of median age 23 years, median body mass index (BMI) 24.8 kg/m(2) and 56% male met inclusion, with 87% (1530/1761) and 86% (1506/1761) follow-up at 2 and 6 years, respectively. At 6 years, n = 592 (39%), n = 131 (9%) and n = 169 (12%) met criteria for models #1 through #3, respectively. The most consistent and strongest independent risk factor at both time-points was subsequent ipsilateral knee surgery. Low 2-year Marx activity score increased the odds of a painful knee at 6 years. CONCLUSIONS Significant knee pain is prevalent after ACLR; with those who undergo subsequent ipsilateral surgery at greatest risk. The relationship between pain and structural OA warrants further study.