Anterior shear strength of the porcine lumbar spine after laminectomy and partial facetectomy

Degenerative lumbar spinal stenosis is the most common reason for lumbar surgery in patients in the age of 65 years and older. The standard surgical management is decompression of the spinal canal by laminectomy and partial facetectomy. The effect of this procedure on the shear strength of the spine has not yet been investigated in vitro. In the present study we determined the ultimate shear force to failure, the displacement and the shear stiffness after performing a laminectomy and a partial facetectomy. Eight lumbar spines of domestic pigs (7 months old) were sectioned to obtain eight L2–L3 and eight L4–L5 motion segments. All segments were loaded with a compression force of 1,600 N. In half of the 16 motion segments a laminectomy and a 50% partial facetectomy were applied. The median ultimate shear force to failure with laminectomy and partial facetectomy was 1,645 N (range 1,066–1,985) which was significantly smaller (p = 0.012) than the ultimate shear force to failure of the control segments (median 2,113, range 1,338–2,659). The median shear stiffness was 197.4 N/mm (range 119.2–216.7) with laminectomy and partial facetectomy which was significantly (p = 0.036) smaller than the stiffness of the control specimens (median 216.5, 188.1–250.2). It was concluded that laminectomy and partial facetectomy resulted in 22% reduction in ultimate shear force to failure and 9% reduction in shear stiffness. Although relatively small, these effects may explain why patients have an increased risk of sustaining shear force related vertebral fractures after spinal decompression surgery

Injury rates and injury risk factors among federal bureau of investigation new agent trainees

<p>Abstract</p> <p>Background</p> <p>A one-year prospective examination of injury rates and injury risk factors was conducted in Federal Bureau of Investigation (FBI) new agent training.</p> <p>Methods</p> <p>Injury incidents were obtained from medical records and injury compensation forms. Potential injury risk factors were acquired from a lifestyle questionnaire and existing data at the FBI Academy.</p> <p>Results</p> <p>A total of 426 men and 105 women participated in the project. Thirty-five percent of men and 42% of women experienced one or more injuries during training. The injury incidence rate was 2.5 and 3.2 injuries/1,000 person-days for men and women, respectively (risk ratio (women/men) = 1.3, 95% confidence interval = 0.9-1.7). The activities most commonly associated with injuries (% of total) were defensive tactics training (58%), physical fitness training (20%), physical fitness testing (5%), and firearms training (3%). Among the men, higher injury risk was associated with older age, slower 300-meter sprint time, slower 1.5-mile run time, lower total points on the physical fitness test (PFT), lower self-rated physical activity, lower frequency of aerobic exercise, a prior upper or lower limb injury, and prior foot or knee pain that limited activity. Among the women higher injury risk was associated with slower 300-meter sprint time, slower 1.5-mile run time, lower total points on the PFT, and prior back pain that limited activity.</p> <p>Conclusion</p> <p>The results of this investigation supported those of a previous retrospective investigation emphasizing that lower fitness and self-reported pain limiting activity were associated with higher injury risk among FBI new agents.</p

Mechanisms and management of loss of response to anti-TNF therapy for patients with Crohn's disease: 3-year data from the prospective, multicentre PANTS cohort study

This is the final version. Available from Elsevier via the DOI in this record. Background We sought to report the effectiveness of infliximab and adalimumab over the first 3 years of treatment and to define the factors that predict anti-TNF treatment failure and the strategies that prevent or mitigate loss of response. Methods Personalised Anti-TNF therapy in Crohn’s disease (PANTS) is a UK-wide, multicentre, prospective observational cohort study reporting the rates of effectiveness of infliximab and adalimumab in anti-TNF-naive patients with active luminal Crohn’s disease aged 6 years and older. At the end of the first year, sites were invited to enrol participants still receiving study drug into the 2-year PANTS-extension study. We estimated rates of remission across the whole cohort at the end of years 1, 2, and 3 of the study using a modified survival technique with permutation testing. Multivariable regression and survival analyses were used to identify factors associated with loss of response in patients who had initially responded to anti-TNF therapy and with immunogenicity. Loss of response was defined in patients who initially responded to anti-TNF therapy at the end of induction and who subsequently developed symptomatic activity that warranted an escalation of steroid, immunomodulatory, or anti-TNF therapy, resectional surgery, or exit from study due to treatment failure. This study was registered with ClinicalTrials.gov, NCT03088449, and is now complete. Findings Between March 19, 2014, and Sept 21, 2017, 389 (41%) of 955 patients treated with infliximab and 209 (32%) of 655 treated with adalimumab in the PANTS study entered the PANTS-extension study (median age 32·5 years [IQR 22·1–46·8], 307 [51%] of 598 were female, and 291 [49%] were male). The estimated proportion of patients in remission at the end of years 1, 2, and 3 were, for infliximab 40·2% (95% CI 36·7–43·7), 34·4% (29·9–39·0), and 34·7% (29·8–39·5), and for adalimumab 35·9% (95% CI 31·2–40·5), 32·9% (26·8–39·2), and 28·9% (21·9–36·3), respectively. Optimal drug concentrations at week 14 to predict remission at any later timepoints were 6·1–10·0 mg/L for infliximab and 10·1–12·0 mg/L for adalimumab. After excluding patients who had primary non-response, the estimated proportions of patients who had loss of response by years 1, 2, and 3 were, for infliximab 34·4% (95% CI 30·4–38·2), 54·5% (49·4–59·0), and 60·0% (54·1–65·2), and for adalimumab 32·1% (26·7–37·1), 47·2% (40·2–53·4), and 68·4% (50·9–79·7), respectively. In multivariable analysis, loss of response at year 2 and 3 for patients treated with infliximab and adalimumab was predicted by low anti-TNF drug concentrations at week 14 (infliximab: hazard ratio [HR] for each ten-fold increase in drug concentration 0·45 [95% CI 0·30–0·67], adalimumab: 0·39 [0·22–0·70]). For patients treated with infliximab, loss of response was also associated with female sex (vs male sex; HR 1·47 [95% CI 1·11–1·95]), obesity (vs not obese 1·62 [1·08–2·42]), baseline white cell count (1·06 [1·02–1·11) per 1 × 10⁹ increase in cells per L), and thiopurine dose quartile. Among patients treated with adalimumab, carriage of the HLA-DQA1*05 risk variant was associated with loss of response (HR 1·95 [95% CI 1·17–3·25]). By the end of year 3, the estimated proportion of patients who developed anti-drug antibodies associated with undetectable drug concentrations was 44·0% (95% CI 38·1–49·4) among patients treated with infliximab and 20·3% (13·8–26·2) among those treated with adalimumab. The development of antidrug antibodies associated with undetectable drug concentrations was significantly associated with treatment without concomitant immunomodulator use for both groups (HR for immunomodulator use: infliximab 0·40 [95% CI 0·31–0·52], adalimumab 0·42 [95% CI 0·24–0·75]), and with carriage of HLA-DQA1*05 risk variant for infliximab (HR for carriage of risk variant: infliximab 1·46 [1·13–1·88]) but not for adalimumab (HR 1·60 [0·92–2·77]). Concomitant use of an immunomodulator before or on the day of starting infliximab was associated with increased time without the development of anti-drug antibodies associated with undetectable drug concentrations compared with use of infliximab alone (HR 2·87 [95% CI 2·20–3·74]) or introduction of an immunomodulator after anti-TNF initiation (1·70 [1·11–2·59]). In years 2 and 3, 16 (4%) of 389 patients treated with infliximab and 11 (5%) of 209 treated with adalimumab had adverse events leading to treatment withdrawal. Nine (2%) patients treated with infliximab and two (1%) of those treated with adalimumab had serious infections in years 2 and 3. Interpretation Only around a third of patients with active luminal Crohn’s disease treated with an anti-TNF drug were in remission at the end of 3 years of treatment. Low drug concentrations at the end of the induction period predict loss of response by year 3 of treatment, suggesting higher drug concentrations during the first year of treatment, particularly during induction, might lead to better long-term outcomes. Anti-drug antibodies associated with undetectable drug concentrations of infliximab, but not adalimumab, can be predicted by carriage of HLA-DQA1*05 and mitigated by concomitant immunomodulator use for both drugs.Guts UKCrohn’s and Colitis UKCure Crohn’s ColitisAbbVieMerck Sharp and DohmeNapp PharmaceuticalsPfizerCelltrion Healthcar

LONG-TERM PERCEIVED DISABILITY FOLLOWING A HAMSTRING INJURY

Jessica Mutchler, Savannah L. McLain, Samuel J. Wilson, Megan Byrd, Benjamin Paquette, Diego Castro-Diaz, Barry A. Munkasy. Georgia Southern University, Statesboro, GA. BACKGROUND: Injuries to the hamstrings complex are one of the most common lower extremity injuries in athletic populations. It is currently unknown how psychological or sociological factors affect an athlete after the recovery process has ended and they’re returned to activity. Therefore, the purpose of this study was to explore long-term perceived disability in physically active adults following a hamstring injury. METHODS: Twenty-six physically active adults with (n=13) and without (n=13) a previous hamstring injury (age 21±1.68 y) completed a Qualtrics survey that included demographic questions for participant matching, the Oslo Sport Trauma’s Hamstring Outcome Score (HaOS), the Injury Psychological Readiness to Return to Sport (I-PRRS), and the Athletic Fear Avoidance Questionnaire (AFAQ). Multiple one-way ANOVAs compared the HaOS subscales and total score, I-PRRS scores, and AFAQ scores between previously injured hamstring individuals and their healthy, matched control after splitting the SPSS data file between competitive (HS_Comp and Con_Comp) and non-competitive athletes (HS_Non-Comp and Con_Non-Comp). RESULTS: There was a significant difference between HS_Non-Comp and Con_Non-Comp groups when comparing Pain subscale (80.71 + 8.5 vs. 98.57+1.96; p \u3c .001; d = 2.89), Function subscale (87.86+11.85, 99.28+1.89; p = 0.027; d = 1.34), and Total HaOS score (81.9+7.22 vs. 92.85+2.21; p = .002; d = 2.05). There were also significant differences in AFAQ scores between HS_Non-Comp and Con_Non-Comp groups (23+11.14 vs. 11.4+3.13; p = 0.05; d = 1.41), but not between the HS_Comp and Con_Comp groups (18.5+12.96 vs. 10.13+0.35; p = 0.09; d = 0.91). CONCLUSION: Non-competitive athletes with a previous hamstring injury reported a greater degree of perceived disability due to pain and function compared to non-competitive athletes with no history of hamstring injury. The results also suggest that fear of re-injury may exist after returning to activity, but confidence in performance may not change after returning to play. Future research should focus on the injury related fear avoidance and why non-competitive athletes had long-term reports of disability whereas competitive athletes did not. Access and utilization of medical professionals by non-competitive and competitive physically active populations following hamstring injury should be explored

Cifoplastia no tratamento da fratura vertebral por insuficiência: avaliação funcional prospectiva Cifoplastia en el tratamiento de la fractura vertebral por insuficiencia: evaluación funcional prospectiva Kyphoplasty in the treatment of vertebral compression fracture: prospective functional evaluation

OBJETIVO: Avaliar o resultado funcional e o grau de satisfação do tratamento cirúrgico utilizando cifoplastia em pacientes com fratura vertebral por insuficiência localizada na coluna tóraco-lombar. MÉTODOS: Foi realizado um estudo prospectivo em pacientes adultos, com diagnóstico de fratura vertebral por insuficiência com evolução superior a oito semanas, apresentando dor no local da fratura e edema ósseo evidente ao exame de RM. A avaliação funcional foi realizada através do Oswestry Disability Index 2.0 e da Escala Visual Analógica de Dor no pré- e pós-operatório. A satisfação pessoal com o tratamento foi quantificada pela escala de Johnson. RESULTADOS: Houve melhora significativa da dor com uma queda média de 6.4 pontos na Escala Visual Analógica de Dor ao final de doze meses de seguimento em comparação ao período pré-operatório (p < 00,5). A avaliação funcional mostrou 88% de resultados excelentes ou bons, sendo que sete pacientes (41%) apresentaram excelentes resultados e oito pacientes (47%) tiveram resultados bons. Dois pacientes (12%) mantiveram sua avaliação funcional inalterada. Quanto à graduação subjetiva de satisfação, 82% declararam-se satisfeitos sendo que 59% estavam completamente satisfeitos e 23% satisfeitos com mínimas restrições. Três pacientes (18%) declararam-se insatisfeitos com o resultado do procedimento. CONCLUSÃO: A cifoplastia mostrou-se efetiva em melhorar a função e liberar a dor em pacientes com fratura vertebral por insuficiência. A ocorrência de uma complicação grave (IAM) chama atenção para a necessidade de suporte hospitalar adequado durante a realização do procedimento.<br>OBJETIVO: Evaluar el resultado funcional y el grado de satisfacción del tratamiento quirúrgico mediante cifoplastia en pacientes con fractura vertebral debido a la insuficiencia situada en la columna toracolumbar. MÉTODOS: Se realizó un estudio prospectivo en pacientes adultos, con diagnóstico de fractura vertebral por insuficiencia, con tiempo de evolución de más de ocho semanas, con dolor en el sitio de la fractura y edema óseo evidente por resonancia magnética. La evaluación funcional se realizó mediante el Índice de Incapacidad de Oswestry 2.0 y la Escala Analógica Visual del Dolor antes y después de la operación. La satisfacción personal con el tratamiento fue medida por la escala de Johnson. RESULTADOS: Una mejora significativa en el dolor con una caída promedio de 6,4 puntos en la escala visual analógica del dolor al final de doce meses de seguimiento, en comparación con el período preoperatorio (p <0,05). La evaluación funcional mostró 88% de resultados excelentes o buenos, con 07 pacientes (41%) que tuvieron resultados excelentes y 08 pacientes (47%) buenos resultados. Dos pacientes (12%) se mantuvieron sin cambios la evaluación funcional. En cuanto al grado subjetivo de satisfacción, 82% dijeron que estaban satisfechos y 59% se mostraron satisfechos por completo, y el 23% satisfechos con restricciones mínimas. Tres pacientes (18%) informaron estar insatisfechos con el resultado del procedimiento. CONCLUSIÓN: La cifoplastia ha demostrado ser eficaz en la mejora de la función y la liberación del dolor en pacientes con fractura vertebral por insuficiencia. La aparición de una complicación grave (Infarto Agudo del Miocardio llama la atención sobre la necesidad de atención hospitalaria adecuada durante el procedimiento.<br>OBJECTIVE: To evaluate the functional outcome and degree of satisfaction of surgical treatment using kyphoplasty in patients with vertebral compression fractures located in the thoracolumbar spine. METHODS: Prospective study in which adult patients diagnosed with vertebral compression fracture with a course over eight weeks, with pain at the fracture site and bone edema evident by MRI imaging were identified and evaluated for the study. The functional evaluation was performed through the Oswestry Disability Index 2.0 and Visual Analogue Scale of Pain pre- and postoperatively. The personal satisfaction with treatment was measured by the scale of Johnson. RESULTS: A significant improvement in pain with an average fall of 6.4 points in the Visual Analogue Scale of Pain at the end of twelve months of follow-up compared to preoperatively (p < 00.5). The functional evaluation showed 88% excellent or good results, with seven patients (41%) with excellent results and eight patients (47%) with good results. Two patients (12%) maintained their functional assessment unchanged. As to the subjective degree of satisfaction, 82% said they were satisfied, and of those, 59% were completely satisfied and 23% satisfied with minimal restrictions. Three patients (18%) reported being dissatisfied with the outcome of the procedure. CONCLUSION: Kyphoplasty has proven effective in improving the function and relieving the pain in patients with vertebral compression fracture. The occurrence of a serious complication (AMI) calls attention to the need for proper hospital care during the procedure