Risk Factors for Unexpected Admission Following Lumbar Spine Laminectomy: A National Database Study.

Introduction Laminectomy is one of the most common orthopedic spine surgeries performed in the United States. Compared to other spine operations such as fusions, laminectomies in isolation are of lower morbidity. However, complications may arise that result in readmission to an inpatient healthcare facility. The purpose of this study is to identify the demographics and risk factors associated with unplanned 30-day readmission following a laminectomy. Methods The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for patients who underwent a laminectomy procedure from 2015 to 2019 using CPT code 63030. This query yielded 61,708 cases. Demographic, lifestyle, comorbidity, and peri-operative factors were recorded. Independent samples Student's t-tests, chi-squared, and, where appropriate, Fisher's exact tests were used in univariate analyses to identify demographic, lifestyle, and peri-operative variables related to 30-day readmission following a laminectomy procedure. Multivariate logistic regression modeling was subsequently performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated and reported. Results Of the 61,708 patients included in our sample, 2,359 were readmitted within 30 days of surgery, corresponding to a readmission rate of 3.82%. Results of the univariate analysis revealed statistically significant relationships between readmission status and the following patient variables: patient age, sex, BMI, ASA classification, race, bleeding disorder, chronic obstructive pulmonary disease (COPD), diabetes, hypertension, congestive heart failure (CHF), chronic steroid use, total operative time, and tobacco use (p < 0.05). Multivariate logistic regression modeling confirmed that the following patient variables were associated with statistically significantly increased odds of readmission: age greater than 65 (p < 0.05), female sex (p = 0.013), bleeding disorder (p = 0.011), diabetes (p = 0.006), current smoker (p = 0.010), COPD (p < 0.001), steroid use (p = 0.006), ASA Class II or above (p < 0.05), and total operative time (p < 0.001). Conclusion Unplanned 30-day readmission after laminectomy is infrequent. However, increasing age, female sex, steroid use, current smokers, bleeding disorders, diabetes, COPD, CHF, a higher ASA classification, and longer operative times are independent risk factors for readmission following laminectomy.

The use of slice encoding for metal artifact correction (SEMAC) sequencing improves the diagnostic evaluation of graft integrity following anterior cruciate ligament reconstruction.

OBJECTIVES: To determine whether magnetic resonance imaging (MRI) with metal artifact reduction sequencing is superior to conventional knee MRI in the evaluation of an injured anterior cruciate ligament (ACL) graft, where visualisation on conventional MRI can be limited by the metal artifact from fixation devices. METHODS: Eighteen patients underwent conventional MRI sequence (proton density fat saturated [PDFS]) and two types of metal artifact reduction sequencing MRI (WARP, slice encoding for metal artifact correction (SEMAC); Siemens) following a secondary injury to their ACL reconstructed knee. Six raters with experience in knee MRI evaluation reviewed sagittal PDFS, WARP, and SEMAC sequences, providing semi-quantitative grades for visualisation and diagnostic confidence assessing the ACL, posterior cruciate ligament , menisci, tibial and femoral tunnel margins, and articular cartilage. Intra-class correlation coefficients for inter-rater reliability were evaluated. The 6-rater mean scores for the visualisation and diagnostic confidence derived from each sequence were compared using the Friedman test for multiple paired samples. RESULTS: No statistically significant difference in the ACL visualisation among the sequences was found (p â€‹= â€‹0.193). Further, a subgroup analysis was performed in cases evaluated as "moderately blurry" or "indistinct ACL visualisation" on PDFS (58% of cases). SEMAC significantly improved diagnostic confidence in ACL visualisation (p â€‹= â€‹0.041) and ACL graft rupture (p â€‹= â€‹0.044) compared to PDFS. There was no statistically significant difference in the inter-observer reliability between sequences. The WARP sequence added 2.84 â€‹± â€‹0.69 â€‹min, while SEMAC added 2.95 â€‹± â€‹0.40 â€‹min to the standard knee MRI scan time. CONCLUSION: use of the SEMAC metal reduction sequence significantly improved diagnostic accuracy and confidence in the detection of ACL graft rupture in cases where the ACL was moderately blurry or indistinct on the PDFS sequence. This sequence should be considered as an adjunct to conventional PDFS in cases where graft visualisation is limited by the metal artifact from fixation devices. LEVEL OF EVIDENCE: III.

A Higher Altitude Is Associated with Increased Incidence of Infections following Primary Total Hip Arthroplasty.

PURPOSE: The purpose of this study was to evaluate whether patients undergoing primary total hip arthroplasty (THA) at a higher elevation have higher rates of: 1) in-hospital length of stay (LOS); 2) surgical site infections (SSIs); 3) periprosthetic joint infections (PJIs); and 4) costs. MATERIALS AND METHODS: The Medicare claims database was used to identify patients who underwent primary THA at an altitude higher than 4,000 feet (ft). High-altitude patients were matched to patients who underwent primary THA at an altitude less than 100 ft, yielding 24,958 and 124,765 patients respectively. Outcomes that were assessed included in-hospital LOS, SSIs, PJIs, and costs of care. A P-value less than 0.001 was considered statistically significant. RESULTS: Patients in the study group had significantly longer in-hospital LOS (4 days vs 3 days, P<0.0001). In addition, patients in the study group had a significantly higher incidence and odds of developing SSIs (1.16% vs 0.86%; odds ratio [OR], 1.34; P<0.0001) and PJIs (0.91% vs 0.58%; OR, 1.56; P<0.0001) within 90-days following the index procedure, compared to matched controls. Higher altitude patients incurred higher day of surgery ($16,139.76 vs $15,279.42; P<0.0001) and 90-day costs ($18,647.51 vs $16,401.62; P<0.0001). CONCLUSION: This study demonstrated that primary THA procedures performed at an elevation higher than 4,000 ft are associated with longer in-hospital LOS, higher rates of SSIs, PJIs, and costs of care. Orthopedists and other healthcare professionals can use this information to provide adequate education for these patients regarding the potential complications that may occur following their procedure.

Adverse childhood experiences predict reaction to multiple sclerosis diagnosis.

OBJECTIVE: At the time of multiple sclerosis (MS) diagnosis, identifying those at risk for poorer health-related quality of life and emotional well-being can be a critical consideration for treatment planning. This study aimed to test whether adverse childhood experiences predict MS patients' health-related quality of life and emotional functioning at time of diagnosis and initial course of disease. METHODS: We recruited patients at the time of new MS diagnosis to complete self-report surveys at baseline and a one-year follow-up. Questionnaires included the Adverse Childhood Experiences (ACEs), as well as the MS Knowledge Questionnaire (MSKQ), the 36-Item Short Form Health Survey (SF-36), and Self-Management Screening (SeMaS). RESULTS: A total of n = 31 participants recently diagnosed with relapsing remitting MS (median EDSS = 1.0, age M = 33.84 ± 8.4 years) completed the study measures. The ACEs significantly predicted health-related quality of life (SF-36) at baseline (Adjusted R 2 = 0.18, p = 0.011) and follow-up (Adjusted R 2 = 0.12, p = 0.03), baseline scores on the SeMaS Depression scale (Adjusted R 2 = 0.19, p = 0.008), as well as follow-up scores on the SeMaS Anxiety (Adjusted R 2 = 0.19, p = 0.014) and SeMaS Depression (Adjusted R 2 = 0.14, p = 0.036) scales. Importantly, increased ACEs scores were predictive of increased anxiety at the one-year follow-up assessment, compared to baseline. CONCLUSIONS: Childhood adversity predicts health-related quality of life and emotional well-being at time of MS diagnosis and over the initial course of the disease. Measured using a brief screening inventory (ACEs), routine administration may be useful for identifying patients in need of increased supportive services.

Crohn's Disease is Associated with Longer In-Hospital Lengths of Stay and Higher Rates of Complications and Costs after Primary Total Hip Arthroplasty.

BACKGROUND: As the incidence and prevalence of Crohn's disease continues to change worldwide, rates within North America have been increasing. The objective of this study was to evaluate whether patients who have Crohn's disease undergoing primary total hip arthroplasties have worse outcomes compared with matched cohorts. Specifically, we evaluated 1) medical complications, 2) in-hospital lengths of stay (LOS), and 3) costs of care. METHODS: Two cohorts of patients who underwent primary total hip arthroplasties from January 1, 2005 to March 31, 2014 were identified from the Medicare claims of the PearlDiver platform. Cohorts were matched by age, sex, and following comorbidities-anemia, diabetes, hyperlipidemia, hypertension, malnutrition, pulmonary disease, and renal failure, yielding 55,361 patients within the study (n = 9229) and matching cohorts (n = 46,132). Outcomes assessed included 90-day medical complications, in-hospital LOS, and costs of care. A P-value less than .005 was considered statistically significant. RESULTS: Patients with Crohn's disease were found to have significantly higher incidences and odds ratios of 90-day medical complications (30.2 vs 13.8; odds ratios: 2.2, P < .0001). They were also found to have significantly longer LOS (3.8- vs 3.6-days, P < .0001) and higher day of surgery ($12,662.00 vs 12,271.15, P < .0001) and 90-day episode costs ($16,933.18 vs $15,670.32, P < .0001). CONCLUSION: Crohn's disease is associated with higher rates of medical complications, longer in-hospital LOS, and increased costs of care. This study may aid physicians to perform appropriate risk adjustment for adverse outcomes and to educate these patients about potential postoperative complications in these patients.

A Simple Model to Estimate Plantarflexor Muscle-Tendon Mechanics and Energetics During Walking With Elastic Ankle Exoskeletons.

GOAL: A recent experiment demonstrated that when humans wear unpowered elastic ankle exoskeletons with intermediate spring stiffness, they can reduce their metabolic energy cost to walk by ∼7%. Springs that are too compliant or too stiff have little benefit. The purpose of this study was to use modeling and simulation to explore the muscle-level mechanisms for the "sweet spot" in stiffness during exoskeleton assisted walking. METHODS: We developed a simple lumped uniarticular musculoskeletal model of the plantarflexors operating in parallel with an elastic "exo-tendon." Using an inverse approach with constrained kinematics and kinetics, we rapidly simulated human walking over a range of exoskeleton stiffness values and examined the underlying neuromechanics and energetics of the biological plantarflexors. RESULTS: Stiffer ankle exoskeleton springs resulted in larger decreases in plantarflexor muscle forces, activations, and metabolic energy consumption. However, in the process of unloading the compliant biological muscle-tendon unit, the muscle fascicles experienced larger excursions that negatively impacted series elastic element recoil that is characteristic of a tuned "catapult mechanism." CONCLUSION: The combination of disrupted muscle-tendon dynamics and the need to produce compensatory forces/moments to maintain overall net ankle moment invariance could explain the "sweet spot" in metabolic performance at intermediate ankle exoskeleton stiffness. Future work will aim to provide experimental evidence to support the model predictions presented here using ultrasound imaging of muscle-level dynamics during walking with elastic ankle exoskeletons. SIGNIFICANCE: Engineers must account for the muscle-level effects of exoskeleton designs in order to achieve maximal performance objectives.

Baseline characteristics of patients predicting suitability for rapid naltrexone induction.

BACKGROUND AND OBJECTIVES: Extended-release (XR) injection naltrexone has proved promising in the treatment of opioid dependence. Induction onto naltrexone is often accomplished with a procedure known as rapid naltrexone induction. The purpose of this study was to evaluate pre-treatment patient characteristics as predictors of successful completion of a rapid naltrexone induction procedure prior to XR naltrexone treatment. METHODS: A chart review of 150 consecutive research participants (N = 84 completers and N = 66 non-completers) undergoing a rapid naltrexone induction with the buprenorphone-clonidine procedure were compared on a number of baseline demographic, clinical and psychosocial factors. Logistic regression was used to identify client characteristics that may predict successful initiation of naltrexone after a rapid induction-detoxification. RESULTS: Patients who failed to successfully initiate naltrexone were younger (AOR: 1.040, CI: 1.006, 1.075), and using 10 or more bags of heroin (or equivalent) per day (AOR: 0.881, CI: 0.820, 0.946). Drug use other than opioids was also predictive of failure to initiate naltrexone in simple bivariate analyses, but was no longer significant when controlling for age and opioid use level. CONCLUSIONS: Younger age, and indicators of greater substance dependence severity (more current opioid use, other substance use) predict difficulty completing a rapid naltrexone induction procedure. Such patients might require a longer period of stabilization and/or more gradual detoxification prior to initiating naltrexone. SCIENTIFIC SIGNIFICANCE: Our study findings identify specific characteristics of patients who responded positively to rapid naltrexone induction.

Undetected Ultracet™ dependence in an adolescent with nonmalignant back pain.

Addiction to painkillers or other substances in pediatric and adolescent cases of noncancer chronic pain is an understudied phenomenon, even amidst documented increases in rates of prescription opioid use and misuse. Case studies can inform the training of clinicians in ethically negotiating a balance between optimizing analgesia and mitigating risk of aberrant drug-taking behaviors. This report discusses an 18-year-old woman with idiopathic scoliosis and clinical depression secondary to undertreated refractory chronic back pain who underwent surgery to correct pseudoarthrosis after a prior spinal instrumentation operation. This intervention in conjunction with a course of patient-controlled analgesia, hydromorphone, and outpatient tramadol, naproxen, methadone, and gabapentin was successful in addressing her long-standing lumbar pain. The patient, however, continued to complain to her pain management team of postsurgical discomfort and insisted on being prescribed Ultracet™ (acetaminophen-tramadol) rather than generic tramadol. The patient's eventual disclosure of severe withdrawal discomfort and history of covert abuse of Ultracet™ is discussed with respect to key warning signs, gaps, and contingencies in the screening, surgical, and pain management processes.

AAV2 mediated retrograde transduction of corticospinal motor neurons reveals initial and selective apical dendrite degeneration in ALS.

Corticospinal motor neurons (CSMN) are the cortical component of motor neuron circuitry, which controls voluntary movement and degenerates in diseases such as amyotrophic lateral sclerosis, primary lateral sclerosis and hereditary spastic paraplegia. By using dual labeling combined with molecular marker analysis, we identified AAV2-2 mediated retrograde transduction as an effective approach to selectively target CSMN without affecting other neuron populations both in wild-type and hSOD1(G93A) transgenic ALS mice. This approach reveals very precise details of cytoarchitectural defects within vulnerable neurons in vivo. We report that CSMN vulnerability is marked by selective degeneration of apical dendrites especially in layer II/III of the hSOD1(G93A) mouse motor cortex, where cortical input to CSMN function is vastly modulated. While our findings confirm the presence of astrogliosis and microglia activation, they do not lend support to their direct role for the initiation of CSMN vulnerability. This study enables development of targeted gene replacement strategies to CSMN in the cerebral cortex, and reveals CSMN cortical modulation defects as a potential cause of neuronal vulnerability in ALS.

Demographic and clinical features of dengue fever in Pakistan from 2003-2007: a retrospective cross-sectional study.

BACKGROUND: Demographic features of dengue fever have changed tremendously in Pakistan over the past two decades. Small scale studies from all over the country have reported different aspects of individual outbreaks during this time. However, there is scarcity of data looking at the overall trend of dengue virus infection in the country. In this study, we examined annual trends, seasonality, and clinical features of dengue fever in the Pakistani population. METHODS: Demographic information and dengue IgM status of all patients tested for dengue IgM antibody at Aga Khan University Hospital from January 2003 to December 2007 were analyzed to look for trends of IgM-positive cases in Pakistan. In addition, clinical and biochemical parameters were abstracted retrospectively from medical records of all patients hospitalized with IgM-proven dengue fever between January 2006 and December 2007. These patients were categorized into dengue fever and dengue hemorrhagic fever according to the WHO severity grading scale. RESULTS: Out of a total of 15,040 patients (63.2% male and 36.8% female), 3952 (26.3%) tested positive for dengue IgM antibody. 209 IgM proven dengue patients were hospitalized during the study period. During 2003, IgM positive cases were seen only during the months of July-December. In contrast, such cases were detected throughout the year from the 2004-2007. The median age of IgM positive patients decreased every year from 32.0 years in 2003 to 24.0 years in 2007 (p<0.001). Among hospitalized patients, nausea was the most common presenting feature found in 124/209 (59.3%) patients. Children presented with a higher median body temperature than adults (p = 0.010). In addition, neutropenia was seen more commonly in children while raised serum ALT levels were seen more commonly in adults (both p = 0.006). While a low total white cell count was more common in patients with dengue fever as compared to Dengue Hemorrhagic Fever (p = 0.020), neutropenia (p = 0.019), monocytosis (p = 0.001) and raised serum ALT level (p = 0.005) were observed more commonly in the latter group. CONCLUSIONS: Dengue virus is now endemic in Pakistan, circulating throughout the year with a peak incidence in the post monsoon period. Median age of dengue patients has decreased and younger patients may be more susceptible. Total and differential leukocyte counts may help identify patients at risk of hemorrhage.

Evaluation of two ELISA assay kits against RT-PCR for diagnosis of dengue virus infection in a hospital setting in Karachi, Pakistan.

OBJECTIVE: To evaluate two commercially available ELISA-based kits against RT-PCR for the diagnosis of dengue virus infection in a Tertiary Care center in Karachi. METHODS: During the 2006 Dengue outbreak, sera were collected from patients clinically classified as dengue fever and graded according to WHO grading. Out of these, 83 samples were selected randomly and analyzed using two different commercial kits (PanBio versus Calbiotech) and were compared with RT-PCR. Clinical charts of the inpatients were also reviewed. Statistical significance was considered at P < or = 0.05. RESULTS: Clinically, a total of 29 (69%) in-patients were diagnosed with dengue haemorrhagic fever, the remaining 13 (30.9%) were diagnosed as dengue fever. Diagnostic PCR was positive in 73 (87.9%) of the total 83 patients. PanBio capture ELISA had a sensitivity of 83.5%. Calbiotech on the other hand, had a sensitivity of 50.7%. The association of PanBio assay with PCR was found to be statistically significant (p<0.001). CONCLUSION: Although RT-PCR is considered as gold standard for diagnosis of dengue virus infection, serological methods play important role in diagnosis as they are cost effective and easily available, especially in dengue endemic countries. Sensitivity and specificity of commercial kits can be variable; therefore evaluation of commercial ELISA kits is important in local setting.