Back to Authors

Nassr, Ahmad

https://orcid.org/0000-0002-7160-734X

Mayo Clinic

Mayo Clinic

Citations 107

Surgical Site Infection Prevention Following Spine Surgery
Aleem, Ilyas , Tan, Lee A. , Aleem, Ilyas S , Nassr, Ahmad , Riew, Kiehyun Daniel

Global Spine Journal | January 6, 2020 | Volume: 10 | Issue: 1_suppl | Pages: 92S-98S

10.1177/2192568219844228 Get It

Study Design: Literature review. Objectives: Surgical site infection (SSI) following spine surgery leads to significant patient morbidity, mortality, and increased health care costs. The purpose of this article is to identify risk factors and strategies to prevent SSIs following spine surgery, with particular focus on avoiding infections in posterior cervical surgery. Methods: We performed a literature review and synthesis to identify methods that can be used to prevent the development of SSI following spine surgery. Specific pearls for preventing infection in posterior cervical spine surgery are also presented. Results: SSI prevention can be divided into patient and surgeon factors. Preoperative patient factors include smoking cessation, tight glycemic control, weight loss, and nutrition optimization. Surgeon factors include screening and treatment for pathologic microorganisms, skin preparation using chlorhexidine and alcohol, antimicrobial prophylaxis, hand hygiene, meticulous surgical technique, frequent irrigation, intrawound vancomycin powder, meticulous multilayered closure, and use of closed suction drains. Conclusion: Prevention of SSI following spine surgery is multifactorial and begins with careful patient selection, preoperative optimization, and meticulous attention to numerous surgical factors. With careful attention to various patient and surgeon factors, it is possible to significantly reduce SSI rates following spine surgery.
Teriparatide treatment increases Hounsfield units in the lumbar spine out of proportion to DEXA changes
Mikula, Anthony L. , Puffer, Ross C. , Jeor, Jeffery D. St. , Bernatz, James T. , Fogelson, Jeremy L. , Sebastian, Arjun S. , Freedman, Brett A. , Currier, Bradford L. , Bydon, Mohamad , Yaszemski, Michael J. , Anderson, Paul A. , Elder, Benjamin D. , Larson, A. Noelle , Nassr, Ahmad

Journal of Neurosurgery: Spine | October 19, 2019 | Volume: 32 | Issue: 1 | Pages: 50-55

10.3171/2019.7.spine19654 Get It

OBJECTIVEThe authors sought to assess whether Hounsfield units (HU) increase following teriparatide treatment and to compare HU increases with changes in bone mineral density (BMD) as measured by dual-energy x-ray absorptiometry (DEXA).METHODSA retrospective chart review was performed from 1997 to 2018 across all campuses at our institution. The authors identified patients who had been treated with at least 6 months of teriparatide and compared HU and BMD as measured on DEXA scans before and after treatment.RESULTSFifty-two patients were identified for analysis (46 women and 6 men, average age 67 years) who underwent an average of 20.9 ± 6.5 months of teriparatide therapy. The mean ± standard deviation HU increase throughout the lumbar spine (L1–4) was from 109.8 ± 53 to 133.9 ± 61 HU (+22%, 95% CI 1.2–46, p value = 0.039). Based on DEXA results, lumbar spine BMD increased from 0.85 to 0.93 g/cm2 (+9%, p value = 0.044). Lumbar spine T-scores improved from −2.4 ± 1.5 to −1.7 ± 1.5 (p value = 0.03). Average femoral neck T-scores improved from −2.5 ± 1.1 to −2.3 ± 1.0 (p value = 0.31).CONCLUSIONSTeriparatide treatment increased both HU and BMD on DEXA in the lumbar spine, without a change in femoral BMD. The 22% improvement in HU surpassed the 9% improvement determined with DEXA. These results support some surgeons’ subjective sense that intraoperative bone quality following teriparatide treatment is better than indicated by DEXA results. To the authors’ knowledge, this is the first study demonstrating an increase in HU with teriparatide treatment.
A Novel Anatomic Landmark to Assess Adequate Decompression in Anterior Cervical Spine Surgery
Aleem, Ilyas , Alder, Jason , Popper, Joseph E., Freedman, Brett A. , Bydon, Mohamad , Yaszemski, Michael J. , Currier, Bradford L. , Nassr, Ahmad

Clinical Spine Surgery: A Spine Publication | August 27, 2019 | Volume: 32 | Issue: 8 | Pages: 345-349

10.1097/bsd.0000000000000877 Get It

Study Design: A retrospective study. Objectives: (1) To assess the reliability of using the posterior endplate valley (PEV) to predict the cranial-caudal location of the cervical pedicle intraoperatively; (2) to assess the impact of age on the cervical PEV-pedicle relationship, interpedicular distance, and foraminal height. Summary of Background Data: The cervical pedicle, which is the anatomic landmark defining the boundaries of the foramen, is hidden from view intraoperatively in the anterior cervical approach, potentially leading to incomplete foraminal decompression. An intraoperative landmark which heralds the location of the pedicle and therefore can be relied upon as a guide for decompression has not been previously described. Methods: We retrospectively reviewed cervical computed tomography images of younger (<50 y) and older (>50 y) patients. Using the coronal reconstructed image taken at the posterior margin of the vertebral body, we constructed a line between the superior aspect of the pedicles and measured the distance from this line to the PEV. Interpedicular distance and foraminal height were also measured. Results: One hundred patients were included in the final analysis. The mean distance (mm) from the pedicular line to the PEV from C3 to C7 respectively was 1.0±0.99, 0.01±0.76, 0.09±0.70, 0.20±0.71, and 0.27±0.79. No significant difference between young and elderly patients was noted (P<0.05). Intervertebral foraminal size was significantly greater in younger compared with elderly patients at all levels except C2–C3. The mean interpedicular distance was 23.05±1.76 mm. Conclusions: This study demonstrates, for the first time, that the PEV is an accurate surgical landmark that is consistently at most 1 mm from the superior aspect of the cervical pedicle in the subaxial spine. Furthermore, this study demonstrated that foraminal height was significantly larger in younger compared with elderly patients at all cervical levels below C3. Level of Evidence: Level 3.
A Review and Clinical Perspective of the Impact of Osteoporosis on the Spine
Carlson, Bayard C. , Robinson, William A. , Wanderman, Nathan , Sebastian, Arjun S. , Freedman, Brett A. , Anderson, Paul A. , Wanderman, Nathan R, Freedman, Brett A , Nassr, Ahmad

Geriatric Orthopaedic Surgery & Rehabilitation | July 17, 2019 | Volume: 10 | Issue: No issue available | Pages: No page available

10.1177/2151459319861591 Get It

Introduction: Osteopenia and osteoporosis are common conditions in the United States. The health consequences of low bone density can be dire, from poor surgical outcomes to increased mortality rates following a fracture. Significance: This article highlights the impact low bone density has on spine health in terms of vertebral fragility fractures and its adverse effects on elective spine surgery. It also reviews the clinical importance of bone health assessment and optimization. Results: Vertebral fractures are the most common fragility fractures with significant consequences related to patient morbidity and mortality. Additionally, a vertebral fracture is the best predictor of a subsequent fracture. These fractures constitute sentinel events in osteoporosis that require further evaluation and treatment of the patient’s underlying bone disease. In addition to fractures, osteopenia and osteoporosis have deleterious effects on elective spine surgery from screw pullout to fusion rates. Adequate evaluation and treatment of a patient’s underlying bone disease in these situations have been shown to improve patient outcomes. Conclusion: With an increased understanding of the prevalence of low bone mass and its consequences as well an understanding of how to identify these patients and appropriately intervene, spine surgeons can effectively decrease the rates of adverse health outcomes related to low bone mass.
Surgical Site Infections in Spine Surgery: Preoperative Prevention Strategies to Minimize Risk
Spina, Nicholas , Aleem, Ilyas , Lawrence, Brandon D. , Nassr, Ahmad

Global Spine Journal | December 13, 2018 | Volume: 8 | Issue: 4_suppl | Pages: 31S-36S

10.1177/2192568217752130 Get It

Study Design: Literature review. Objectives: A review of the literature identifying preoperative risk factors for developing surgical site infections after spine surgery and discussion of the preventive strategies to minimize risks. Methods: A review of the literature and synthesis of the data to provide an updated review on the preoperative management of surgical site infection. Results: Preoperative prevention strategies of reducing surgical site infections in spine surgery remains a challenging problem. Careful mitigation of modifiable patient comorbidities, blood glucose control, smoking, obesity, and screening for pathologic microorganisms is paramount to reduce this risk. Individualized antibiotic regimens, skin preparation, and hand hygiene also play a critical role in surgical site infection prevention. Conclusions: This review of the literature discusses the preoperative preventive strategies and risk management techniques of surgical site infections in spine surgery. Significant decreases in surgical site infections after spine surgery have been noted over the past decade due to increased awareness and implementation of the prevention strategies described in this article. However, it is important to recognize that prevention of surgical site infection requires a system-wide approach that includes the hospital system, the surgeon, and the patient. Continued efforts should focus on system-wide implementation programs including careful patient selection, individualized antibiotic treatment algorithms, identification of pathologic organisms, and preoperative decolonization programs to further prevent surgical site infections and optimize patient outcomes.
Office-Based Mesenchymal Stem Cell Therapy for the Treatment of Musculoskeletal Disease: A Systematic Review of Recent Human Studies
Law, Luke, Wijnen, André J. van , Eldrige, Jason S. , Mauck, William D. , Pingree, Mathew J., Yang, Juan , Muir, Casey W, Erwin, Patricia J., Bydon, Mohamad , Qu, Wenchun , van Wijnen, Andre J , Hunt, Christine , Nassr, Ahmad , Larson, A. Noelle , Muir, Casey

Pain Medicine | December 3, 2018 | Volume: 20 | Issue: 8 | Pages: 1570-1583

10.1093/pm/pny256 Get It

Abstract Background The use of mesenchymal stem cells (MSCs) in clinical applications for the treatment of musculoskeletal disease is steadily increasing in office-based practice. The so-called “first generation” of MSCs is defined as autologous stem cells that have undergone minimal manipulation and are used for a homologous purpose. Systematic reviews of the clinical trials completed to date of such MSCs enable practitioners to better understand what is currently known about the outcomes and side effects of such treatments. Study Design A systematic review of human clinical studies of office-based MSC therapy for the treatment of painful degenerative musculoskeletal conditions. Methods A search of the Ovid MEDLINE, EMBASE, and Scopus databases was conducted from 2006 through September 2016. Seven hundred sixty-one records were identified from database searching, and two records from reference review of included papers. Studies with human subjects that evaluated treatment of musculoskeletal disease with minimally manipulated MSCs were included. Results Eight studies were included in this review based on selection criteria. A total of 941 patients were included, 841 of whom received cellular products, and no significant adverse events were reported. Symptomatology generally improved, though no differences were seen over controls where present. Conclusion Support in the literature is strongest for the use of bone marrow aspirate concentrate (BMAC) injections for the treatment of knee pain, but applications of the use of BMAC and peripheral blood–derived MSCs for the treatment of hip pain, tendon pain, and disc pain have all been reported. Further research is required, with large randomized controlled trials.
Do Cervical Spine Surgery Patients Recall Their Preoperative Status?
Aleem, Ilyas , Currier, Bradford L. , Yaszemski, Michael J. , Poppendeck, Heidi, Huddleston, P.M. , Eck, Jason C., Rhee, John M. , Bydon, Mohamad , Freedman, Brett A. , Huddleston, Paul, Nassr, Ahmad , Huddleston, Paul M

Clinical Spine Surgery: A Spine Publication | October 5, 2018 | Volume: 31 | Issue: 10 | Pages: E481-E487

10.1097/bsd.0000000000000726 Get It

Study Design: This is a prospective cohort study. Objective: To characterize the accuracy of patient recollection of preoperative symptoms after cervical spine surgery. Summary of Background Data: Recall bias is a well-known source of systematic error. The accuracy of patient recall after cervical spine surgery remains unknown. Methods: Consecutive patients undergoing cervical spine surgery for myelopathy or radiculopathy were enrolled. Neck and arm numeric pain scores and Neck Disability Indices were recorded preoperatively. Patients were asked to recall their preoperative status at either short (<1 y) or long-term (≥1 y) follow-up. Actual and recalled scores were compared using paired t tests and relations were quantified using the Pearson correlation coefficients. Multivariable linear regression was used to identify factors impacting recollection. Results: In total, 73 patients with a mean age of 58.2 years were included. Compared with their preoperative scores, patients showed significant improvement in neck pain [mean difference (MD)=−2.9; 95% confidence intervals (CIs), −3.5 to −2.3], arm pain (MD, −3.4; 95% CI, −4.0 to −2.8), and disability (MD, −12.4%; 95% CI, −16.9 to −7.9). Patient recollection of preoperative status was significantly more severe than actual for neck pain (MD, +1.5; 95% CI, 0.8–2.2), arm pain (MD, +2.3; 95% CI, 1.6–3.0), and disability (MD, +5.8%; 95% CI, 2.4–9.2). Moderate correlation between actual and recalled scores with regard to neck (r=0.41), arm (r=0.50) pain, and disability (r=0.67) was seen. This was maintained across age, sex, and time between date of surgery and recollection. Over 30% of patients switched their predominant symptom from neck-to-arm pain or vice versa on recall of their preoperative symptoms. Conclusions: Relying on patient recollection does not provide an accurate measure of preoperative status after cervical spine surgery. Prospective and not retrospective collection of patient-reported outcomes remain the gold standard to measure and interpret outcomes after cervical spine surgery. Recall bias has the potential to affect patient satisfaction and requires further study.
Does patient selection account for the perceived cost savings in outpatient spine surgery? A meta-analysis of current evidence and analysis from an administrative database
Mundell, Benjamin F. , Gates, Marcus, Kerezoudis, Panagiotis , Alvi, Mohammed Ali , Freedman, Brett A. , Hohmann, Samuel F. , Bydon, Mohamad , Gates, Marcus J, Alvi, Mohammed Ali , Nassr, Ahmad

Journal of Neurosurgery: Spine | September 14, 2018 | Volume: 29 | Issue: 6 | Pages: 687-695

10.3171/2018.4.spine1864 Get It

OBJECTIVEFrom 1994 to 2006 outpatient spinal surgery increased 5-fold. The perceived cost savings with outcomes comparable to or better than those achieved with inpatient admission for the same procedures are desirable in an era where health expenditures are scrutinized. The increase in outpatient spine surgery is also driven by the proliferation of ambulatory surgery centers. In this study, the authors hypothesized that the total savings in outpatient spine surgery is largely driven by patient selection and biases toward healthier patients.METHODSA meta-analysis assessed patient selection factors and outcomes associated with outpatient spine procedures. Pooled odds ratios and mean differences were calculated using a Bayesian random-effects model. The authors extended this analysis in a novel way by using the results of the meta-analysis to examine cost data from an administrative database of academically affiliated hospitals. A Bayesian approach with priors informed by the meta-analysis was used to compare costs for inpatient and outpatient performance of anterior cervical discectomy and fusion (ACDF) and lumbar laminectomy.RESULTSSixteen studies with a total of 370,195 patients met the inclusion criteria. Outpatient procedures were associated with younger patient age (mean difference [MD] −2.34, 95% credible interval [CrI] −4.39 to −0.34) and no diabetes diagnosis (odds ratio [OR] 0.78, 95% CrI 0.54–0.97). Outpatient procedures were associated with a lower likelihood of reoperation (OR 0.42, 95% CrI 0.16–0.80), 30-day readmission (OR 0.39, 95% CrI 0.16–0.74), and complications (OR 0.29, 95% CrI 0.15–0.50) and with lower overall costs (MD −$121,392.72, 95% CrI −$216,824.81 to −$23,632.92). Additional analysis of the national administrative data revealed more modest cost savings than those found in the meta-analysis for outpatient spine surgeries relative to inpatient spine surgeries. Estimated cost savings for both younger patients ($555 for those age 30–35 years [95% CrI −$733 to −$374]) and older patients ($7290 for those age 65–70 years [95% CrI −$7380 to −$7190]) were less than the overall cost savings found in the meta-analysis.CONCLUSIONSCompared to inpatient spine surgery, outpatient spine surgery was associated with better short-term outcomes and an initial reduction in direct costs. A selection bias for outpatient procedures toward younger, healthier patients may confound these results. The additional analysis of the national database suggests that cost savings in the outpatient setting may be less than previously reported and a result of outpatient procedures being offered more frequently to younger and healthier individuals.
Management of Sacrococcygeal Chordoma
Ahmed, Ahmed T. , Morsy, Mohamed , Mustafa, Karim, Testini, Paola, Aleem, Ilyas , Murad, M. Hassan , Murad, Mohammad Hassan, Murad, M Hassan , Abdel-Rahman, Omar Mohammed , Nassr, Ahmad

Spine | March 14, 2018 | Volume: 43 | Issue: 19 | Pages: E1157-E1169

10.1097/brs.0000000000002638 Get It

Study Design. Systematic review and meta-analysis of observational studies. Objective. The aim of the study is to evaluate different treatment modalities in the management of sacrococcygeal chordoma. Summary of Background Data. Chordomas are primary malignant bone tumors associated with considerable morbidity and mortality. Methods. We searched MEDLINE, EMBASE, Cochrane Central-Register of Controlled Trials, and Scopus from inception to July 2015. Eligible studies included patients with sacrococcygeal chordoma treated exclusively with surgery, radiotherapy, or both. Two reviewers independently assessed the eligibility of potential studies, risk of bias, and extracted data. Outcomes of interest were all-cause mortality, progression-free survival, and metastases. We analyzed further surgical outcomes by resection margin. All outcomes were assessed at 60 months and more than 60 months following intervention. Results. We included 33 noncomparative studies reporting on 501 patients (mean age 57 years). Overall mortality rate was (16%) after surgical resection with adjuvant radiotherapy and (28%) after surgical resection, and (43%) after radiotherapy (P = 0.28). All-cause mortality following wide surgical resection was (32%) compared to (40%) after marginal resection (P = 0.51). Overall progression-free survival rate was (58%) after surgical resection with adjuvant radiotherapy and (55%) after surgery (P = 0.92). However, at more than 60 months follow-up, progression-free survival rates were significantly higher (P = 0.024) following surgical resection with adjuvant radiotherapy (74%) in comparison to surgery (55%) and radiotherapy (36%). Overall progression-free survival rates were nonsignificantly higher after wide surgical resection (66%) than marginal resection (33%) (P = 0.16). However, at 60 months follow-up, progression-free survival rates were significantly higher following wide surgical resection (73%) than marginal resection (33%) (P = 0.047). Conclusion. Sacrococcygeal chordoma is a difficult to treat disease entity. Until comparative studies become available, wide surgical resection and multidisciplinary management are the recommended approaches to improve patient outcomes. Level of Evidence: 3
The 2017 Cervical Spine Research Society International Traveling Fellowship
Scemama, Caroline, Tornero, Eduardo, Mesfin, Addisu , Zhou, Feifei , Kaito, Takashi , Nassr, Ahmad

Spine | December 13, 2017 | Volume: 43 | Issue: 4 | Pages: 235-238

10.1097/brs.0000000000002523 Get It