Drivers of surgery for the degenerative hip, knee, and spine: a systematic review.

BACKGROUND: Surgical treatment for degenerative conditions of the hip, knee, and spine has an impact on overall healthcare spending. Surgical rates have increased dramatically and considerable regional variation has been observed. The reasons behind these increasing rates and variation across regions have not been well elucidated. QUESTIONS/PURPOSES: We therefore identified demographic (D), social structure (SS), health belief (HB), personal (PR) and community resources (CR), and medical need (MN) factors that drive rates of hip, knee, and spine surgery. METHODS: We conducted a systematic review to include all observational, population-based studies that compared surgical rates with potential drivers (D, SS, HB, PR, CR, MN). We searched PubMed combining key words focusing on (1) disease and procedure; (2) study methodology; and (3) explanatory models. Independent investigators selected potentially eligible studies from abstract review and abstracted methodological and outcome data. From an initial search of 256 articles, we found 37 to be potentially eligible (kappa 0.86) but only 28 met all our inclusion criteria. RESULTS: Age, nonminority, insurance coverage, and surgeon enthusiasm all increased surgical rates. Rates of arthroplasty were higher for females with higher education, income, obesity, rurality, willingness to consider surgery, and prevalence of disease, whereas spinal rates increased with male gender, lower income, and the availability of advanced imaging. CONCLUSIONS: Regional variation in these procedures exists because they are examples of preference-sensitive care. With strategies that may affect change in factors that are potentially modifiable by behavior or resources, extreme variation in rates may be reduced.

Second opinion in spine surgery: A scoping review.

BACKGROUND: As a growing number of patients seek consultations for increasingly complex and costly spinal surgery, it is of both clinical and economic value to investigate the role for second opinions (SOs). Here, we summarized and focused on the shortcomings of 14 studies regarding the role and value of SOs before proceeding with spine surgery. METHODS: Utilizing PubMed, Google Scholar, and Scopus, we identified 14 studies that met the inclusion criteria that included: English, primary articles, and studies published in the past 20 years. RESULTS: We identified the following findings regarding SO for spine surgery: (1) about 40.6% of spine consultations are SO cases; (2) 61.3% of those received a discordant SO; (3) 75% of discordant SOs recommended conservative management; and (4) SO discordance applied to a variety of procedures. CONCLUSION: The 14 studies reviewed regarding SOs in spine surgery showed that half of the SOs differed from those given in the initial consultation and that SOs in spine surgery can have a substantial impact on patient care. Absent are prospective studies investigating the impact of following a first versus second opinion. These studies are needed to inform the potential benefit of universal implementation of SOs before major spine operations to potentially reduce the frequency and type/extent of surgery.

Impact of Cirrhosis on Morbidity and Mortality After Spinal Fusion.

STUDY DESIGN: Retrospective large database study. OBJECTIVE: To determine the impact of cirrhosis on perioperative outcomes and resource utilization in elective spinal fusion surgery. METHODS: Elective spinal fusion hospitalizations in patients with and without cirrhosis were identified using ICD-9-CM codes between the years of 2009 and 2011 using the Nationwide Inpatient Sample database. Main outcome measures were in-hospital neurologic, respiratory, cardiac, gastrointestinal, renal and urinary, pulmonary embolism, wound-related complications, and mortality. Length of stay and inpatient costs were also collected. Multivariable logistic regressions were conducted to compare the in-hospital outcomes of patients with and without cirrhosis undergoing spinal fusion. RESULTS: A total of 1 214 694 patients underwent elective spinal fusions from 2009 to 2011. Oh these, 6739 were cirrhotic. Cirrhosis was a significant independent predictor for respiratory (odds ratio [OR] = 1.43, confidence interval [CI] 1.29-1.58; P < .001), gastrointestinal (OR = 1.72, CI 1.48-2.00; P < .001), urinary and renal (OR = 1.90, CI 1.70-2.12; P < 0.001), wound (OR = 1.36, CI 1.17-1.58; P < 0.001), and overall inpatient postoperative complications (OR = 1.43, CI 1.33-1.53; P < .001). Cirrhosis was also independently associated with significantly greater inpatient mortality (OR = 2.32, CI 1.72-3.14; P < .001). Cirrhotic patients also had significantly longer lengths of stay (5.35 vs 3.35 days; P < .001) and inpatient costs ($36 738 vs $29 068; P < .001). CONCLUSIONS: Cirrhosis is associated with increased risk of perioperative complications, mortality and greater resource utilization. Cirrhotic patients undergoing spinal fusion surgeries should be counseled on these increased risks. Current strategies for perioperative management of cirrhotic patients undergoing spinal fusion surgery need improvement.

Outcomes and Complications After Spinal Fusion in Patients With Obstructive Sleep Apnea.

STUDY DESIGN: Retrospective database study. OBJECTIVE: To investigate the impact obstructive sleep apnea (OSA) has on perioperative complications, inpatient mortality, and costs in patients undergoing spinal fusions. METHODS: Hospitalizations for spinal fusion surgery between the years 2009 and 2011 were identified using the Nationwide Inpatient Sample and grouped into patients with and without OSA. Patient demographic data, comorbidities, hospital characteristics, hospitalization outcomes, and costs were extracted and compared. Multivariable logistic regressions were conducted to compare the in-hospital outcomes of patients undergoing spinal fusion with and without OSA. RESULTS: A total of 107 451 (7.7%) OSA patients who underwent spinal fusions were identified from 2009 to 2011. Compared with patients without OSA, OSA patients were significantly older, more likely to be male, and have significantly greater comorbidity burden. Multivariable regression analysis demonstrated that OSA had a significant independent association with slightly increased respiratory (odds ratio [OR] = 1.13, confidence interval [CI] = 1.09-1.16; P < .001), urinary and renal (OR = 1.11, CI = 1.07-1.16; P < .001) or overall inpatient complications (OR = 1.05, CI = 1.02-1.05; P < .001). OSA was also independently associated with significantly lower inpatient mortality (OR = 0.39, CI = 0.33-0.45; P < .001). CONCLUSIONS: While OSA confers greater comorbidity burden and is associated with slightly higher inpatient complication rates following spinal fusions, diagnosed OSA was not an independent predictor of inpatient mortality. A cautious interpretation of this finding is that on a national level, the current methods of preoperative medical optimization and inpatient management of OSA are satisfactory.

Impact of Sickle Cell Anemia on Inpatient Morbidity After Spinal Fusion.

STUDY DESIGN: A retrospective study. OBJECTIVE: To determine the impact of sickle cell anemia on perioperative outcomes and resource utilization in elective spinal fusion surgery. SUMMARY OF BACKGROUND DATA: Sickle cell anemia has been identified as an important surgical risk factor in otolaryngology, cardiothoracic surgery, general surgery, and total joint arthroplasty. However, the impact of sickle cell anemia on elective spine surgery is unknown. METHODS: Hospitalizations for elective spinal fusion surgery between the years of 2001-2014 from the US National Inpatient Sample were identified using ICD-9-CM codes and patients were grouped into those with and without sickle cell anemia. The main outcome measures were in-hospital neurological, respiratory, cardiac, gastrointestinal, renal and urinary, pulmonary embolism, and wound-related complications and mortality. Length of stay and inpatient costs were also collected. Multivariable logistic regressions were conducted to compare the in-hospital outcomes of patients undergoing elective spinal fusion with or without sickle cell anemia. RESULTS: From a total of 4,542,719 patients undergoing elective spinal fusions from 2001 to 2014, 456 sickle cell disease patients were identified. Sickle cell anemia is a significant independent predictor for pulmonary embolism [odds ratio (OR)=7.37; confidence interval (CI), 4.27-12.71; P<0.001], respiratory complications (OR=2.36; CI, 1.63-3.42; P<0.001), wound complications (OR=3.84; CI, 2.72-5.44; P<0.001), and overall inpatient complications (OR=2.58; CI, 2.05-3.25; P<0.001). Sickle cell anemia patients also have significantly longer length of stay (7.0 vs. 3.8 d; P<0.001) and higher inpatient costs ($20,794 vs. $17,608 P<0.05). CONCLUSIONS: Sickle cell anemia is associated with increased risk of perioperative complications and greater health care resource utilization. Sickle cell anemia patients undergoing spinal fusion surgeries should be counseled on these increased risks. Moreover, current strategies for perioperative management of sickle cell anemia patients undergoing spinal fusion surgery need to be improved.

Pseudo-Pedicle Heterotopic Ossification From Use of Recombinant Human Bone Morphogenetic Protein 2 (rhBMP-2) in Transforaminal Lumbar Interbody Fusion Cages.

We conducted a study to determine the common characteristics of patients who developed radiculopathy symptoms and corresponding heterotopic ossification (HO) from transforaminal lumbar interbody fusions (TLIF) using recombinant human bone morphogenetic protein 2 (rhBMP-2). HO can arise from a disk space with rhBMP-2 use in TLIF. Formation of bone around nerve roots or the thecal sac can cause a radiculopathy with a consistent pattern of symptoms. We identified 38 patients (26 males, 12 females) with a mean (SD) age of 50.8 (7.5) years who developed radiculopathy symptoms and corresponding HO from TLIF with rhBMP-2 in the disk space between 2002 and 2015. To document this complication and improve its recognition, we recorded common patterns of symptom development and radiologic findings: specifically, time from implantation of rhBMP-2 to symptom development, consistency with side of TLIF placement, and radiologic findings. Radicular pain generally developed a mean (SD) of 3.8 (1.0) months after TLIF with rhBMP-2. Development of radiculopathy symptoms corresponded to consistent "pseudo-pedicle"-like HO. In all 38 patients, HO arising from the annulotomy site showed a distinct pseudo-pedicle pattern encompassing nerve roots and the thecal sac. In addition, development of radiculopathy symptoms and corresponding HO appear to be independent of amount of rhBMP-2. HO resulting from TLIF with rhBMP-2 in the disk space is a pain generator and a recognizable complication that can be diagnosed by assessment of symptoms and computed tomography characteristics.

Does Addition of Tobramycin Powder Reduce Infection Rates After Spine Surgery?

STUDY DESIGN: Retrospective chart review. OBJECTIVES: To evaluate the efficacy of tobramycin and vancomycin powder in reducing surgical site infections in posterior lumbar instrumented fusion. METHODS: A multicenter, electronic database search was conducted for all patients who underwent posterior instrumented lumbar fusions. RESULTS: The addition of vancomycin powder decreased postoperative infections from an incidence of 5.7% down to a rate of 2.0%. This difference was statistically significant (P = .018). The addition of tobramycin powder to the wound in addition to vancomycin further decreased the infection rate down to 1.8%. The postoperative infection rate was statistically significant (P = .041) when compared with the no-powder group. However, the difference was not statistically significant (P = 1.00) when compared with vancomycin alone. There was also a trend toward gram-negative organisms with the addition of more antibiotic powder. In the control group, for example, the organisms cultured were 66% methicillin-sensitive Staphylococcus aureus and 33% gram-negative organisms. In the vancomycin group, 30% of the organisms cultured were Staphylococcus aureus and 60% gram-negative organisms. In the vancomycin and tobramycin powder group, 100% of the organisms cultured were gram-negative. CONCLUSIONS: There is a reduction in surgical site infections with addition of antibiotic powder to the wound prior to closure. However, the reduction in the infection rate was not as great with the addition of tobramycin powder to vancomycin alone and there was a noticeable change in the spectrum of organism cultured with this addition. Clinicians should consider the risk-to-benefit ratio in each case when deciding to use antibiotic powder.

Advances in spinal fusion.

Since its initial description about a century ago, spinal fusion has become a common surgical intervention in the treatment of various debilitating spinal disorders. However, given the complexities and demands of the procedure, patient selection remains a key component in the success of the operation. In this article, we will review the various indications for spinal fusion, the current advances in fusion techniques, as well as the potential complications associated with the procedure.

New method for determining apparent axial center of rotation of lumbar and thoracic spine segments.

One main question in spinal kinematics is the determination of the spine's apparent axial center of rotation. Previous research on this topic has yielded contradictory results. The objective of this study was to determine the apparent axial center of rotation for seven lumbar and six thoracic spinal segments by developing and validating a new method. A custom six-degree-of-freedom device, allowing full range of motion, was used with motion recording and analysis software. This system tracked a grid of markers on a specimen when rotational torque was applied in both clockwise and counterclock wise directions at 3.53 Nm, 7.05 Nm, 10.58 Nm, and 14.10 Nm. The area encompassing the apparent axial center of rotation was determined by identifying the five markers with the least amount of motion. The marker angular displacement was calculated as the angle between a virtual line drawn between two points in the initial and final torque conditions. Rotation in both directions was averaged. The lumbar and thoracic spinal segments averaged an apparent axial center of rotation at the posterior border of the vertebral endplates and the anterior border of the spinal canal, with average clockwise to counterclockwise angular displacement ratios of 0.87 and 0.97, respectively.