Jesse E. Bible

Radiation Exposure from Musculoskeletal Computerized Tomographic Scans

BACKGROUND Computerized tomographic scans are routinely obtained to evaluate a number of musculoskeletal conditions. However, since computerized tomographic scans expose patients to the greatest amounts of radiation of all imaging modalities, the physician must be cognizant of the effective doses of radiation that are administered. This investigation was performed to quantify the effective doses of computerized tomographic scans that are performed for various musculoskeletal applications. METHODS The digital imaging archive of a single institution was retrospectively reviewed to identify helical computerized tomographic scans that were completed to visualize the extremities or spine. Imaging parameters were recorded for each examination, and dosimetry calculator software was used to calculate the effective dose values according to a modified protocol derived from publication SR250 of the National Radiological Protection Board of the United Kingdom. Computerized tomographic scans of the chest, abdomen, and pelvis were also collected, and the effective doses were compared with those reported by prior groups in order to validate the results of the current study. RESULTS The mean effective doses for computerized tomographic scans of the chest, abdomen, and pelvis (5.27, 4.95, and 4.85 mSv, respectively) were consistent with those of previous investigations. The highest mean effective doses were recorded for studies evaluating the spine (4.36, 17.99, and 19.15 mSv for the cervical, thoracic, and lumbar spines, respectively). In the upper extremity, the effective dose of a computerized tomographic scan of the shoulder (2.06 mSv) was higher than those of the elbow (0.14 mSv) and wrist (0.03 mSv). Similarly, the effective dose of a hip scan (3.09 mSv) was significantly higher than those observed with knee (0.16 mSv) and ankle (0.07 mSv) scans. CONCLUSIONS Computerized tomographic scans of the axial and appendicular skeleton are associated with substantially elevated radiation exposures, but the effective dose declines substantially for anatomic structures that are further away from the torso.

Weight Lifting and Aortic Dissection: More Evidence for a Connection

Background/Aims: In 2003, we reported on a small number of patients in whom acute aortic dissection appeared to be causally related to intense weight lifting. If additional cases could be identified, the phenomenon of weight lifting induced aortic dissection would be further substantiated. We now report a substantially larger number of cases in which aortic dissection is associated with intense physical exertion. Methods: Additional cases of acute aortic dissection occurring at the time of intense physical exertion were accumulated and analyzed. Cases were culled from retrospective review of a large university data base and from reports forwarded to our attention from around the country. We determined type of activity bringing on symptoms, age and sex of the patients, location of the dissection (ascending or descending aorta), aortic size, therapy, and survival. Results: We identified 31 patients in whom acute aortic dissection occurred in the context of severe physical exertion, predominantly weight lifting or similar activities. All patients except one were males. Mean age was 47.3 (range = 19–76). All except four dissections were in the ascending aorta. Only three patients (9.7%) had a family history of aortic disease. Mean aortic diameter on the initial imaging study was 4.63 cm. Twenty-six of the 31 cases were diagnosed ante-mortem and 5 post-mortem. Overall, 10 of the 31 patients (32.2%) died. Of 24 patients reaching surgical therapy, 20 (83.3%) survived. Conclusion: Weight lifting related acute aortic dissection appears to be a real phenomenon, with increasing evidence for the association of extreme exertion with this catastrophic aortic event. Moderate aortic dilatation confers vulnerability to exertion-related aortic dissection. Individuals with known aortic dilatation should be cautioned to refrain from weight lifting or strenuous exertion. Routine echocardiographic screening of individuals engaging in heavy strength training should be considered, in order to prevent this tragic loss of life.

Normal functional range of motion of the cervical spine during 15 activities of daily living.

Study Design Prospective clinical study. Objective The purpose of this investigation was to quantify normal cervical range of motion (ROM) and compare these results to those used to perform 15 simulated activities of daily living (ADLs) in asymptomatic subjects. Summary of Background Data Previous studies looking at cervical ROM during ADLs have been limited and used measuring devices that do not record continuous motion. The purpose of this investigation was to quantify normal cervical ROM and compare these results with those used to perform 15 simulated ADLs in asymptomatic subjects. Methods A noninvasive electrogoniometer and torsiometer were used to measure the ROM of the cervical spine. The accuracy and reliability of the devices were confirmed by comparing the ROM values acquired from dynamic flexion/extension and lateral bending radiographs to those provided by the device, which was activated while the radiographs were obtained. Intraobserver reliability was established by calculating the intraclass correlation coefficient for repeated measurements on the same subjects by 1 investigator on consecutive days. These tools were employed in a clinical laboratory setting to evaluate the full active ROM of the cervical spines (ie, flexion/extension, lateral bending, and axial rotation) of 60 asymptomatic subjects (30 females and 30 males; age, 20 to 75 y) as well as to assess the functional ROM required to complete 15 simulated ADLs. Results When compared with radiographic measurements, the electrogoniometer was found to be accurate within 2.3±2.2 degrees (mean±SD) and the intraobserver reliabilities for measuring the full active and functional ROM were both excellent (intraclass correlation coefficient of 0.96 and 0.92, respectively). The absolute ROM and percentage of full active cervical spinal ROM used during the 15 ADLs was 13 to 32 degrees and 15% to 32% (median, 20 degrees/19%) for flexion/extension, 9 to 21 degrees and 11% to 27% (14 degrees/18%) for lateral bending, and 13 to 57 degrees and 12% to 92% (18 degrees/19%) for rotation. Backing up a car required the most ROM of all the ADLs, involving 32% of sagittal, 26% of lateral, and 92% of rotational motion. In general, personal hygiene ADLs such as washing hands and hair, shaving, and applying make-up entailed a significantly greater ROM relative to locomotive ADLs including walking and traveling up and down a set of stairs (P<0.0001); in addition, compared with climbing up these steps, significantly more sagittal and rotational motion was used when descending stairs (P=0.003 and P=0.016, respectively). When picking up an object from the ground, a squatting technique required a lower percentage of lateral and rotational ROM than bending at the waist (P=0.002 and P<0.0001). Conclusions By quantifying the amounts of cervical motion required to execute a series of simulated ADLs, this study indicates that most individuals use a relatively small percentage of their full active ROM when performing such activities. These findings provide baseline data which may allow clinicians to accurately assess preoperative impairment and postsurgical outcomes.

Preoperative Opioid Use as a Predictor of Adverse Postoperative Self-Reported Outcomes in Patients Undergoing Spine Surgery

BACKGROUND Opioids are commonly used for preoperative pain management in patients undergoing spine surgery. The objective of this investigation was to assess whether preoperative opioid use predicts worse self-reported outcomes in patients undergoing spine surgery. METHODS Five hundred and eighty-three patients undergoing lumbar, thoracolumbar, or cervical spine surgery to treat a structural lesion were included in this prospective cohort study. Self-reported preoperative opioid consumption data were obtained at the preoperative visit and were converted to the corresponding daily morphine equivalent amount. Patient-reported outcome measures were assessed at three and twelve months postoperatively via the 12-Item Short-Form Health Survey and the EuroQol-5D questionnaire, as well as, when appropriate, the Oswestry Disability Index and the Neck Disability Index. Separate multivariable linear regression analyses were then performed. RESULTS At the preoperative evaluation, of the 583 patients, 56% (326 patients) reported some degree of opioid use. Multivariable analyses controlling for age, sex, diabetes, smoking, surgery invasiveness, revision surgery, preoperative Modified Somatic Perception Questionnaire score, preoperative Zung Depression Scale score, and baseline outcome score found that increased preoperative opioid use was a significant predictor (p < 0.05) of decreased 12-Item Short-Form Health Survey and EuroQol-5D scores, as well as of increased Oswestry Disability Index and Neck Disability Index scores at three and twelve months postoperatively. Every 10-mg increase in daily morphine equivalent amount taken preoperatively was associated with a 0.03 decrease in the 12-Item Short-Form Health Survey physical component summary and mental component summary scores, a 0.01 decrease in the EuroQol-5D score, and a 0.5 increase in the Oswestry Disability Index and Neck Disability Index score at twelve months postoperatively. Higher preoperative Modified Somatic Perception Questionnaire and Zung Depression Scale scores were also significant negative predictors (p < 0.05). CONCLUSIONS Increased preoperative opioid consumption, Modified Somatic Perception Questionnaire score, and Zung Depression Scale score prior to undergoing spine surgery predicted worse patient-reported outcomes. This suggests the potential benefit of psychological and opioid screening with a multidisciplinary approach that includes weaning of opioid use in the preoperative period and close opioid monitoring postoperatively. LEVEL OF EVIDENCE Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Preoperative opioid use and its association with perioperative opioid demand and postoperative opioid independence in patients undergoing spine surgery.

Study Design. Prospective cohort. Objective. To assess whether preoperative opioid use is associated with increased perioperative opioid demand and postoperative opioid independence in patients undergoing spine surgery. Summary of Background Data. Previous work has demonstrated increased opioid requirements during the intraoperative and immediate postoperative period in patients with high levels of preoperative opioid use. Despite this, they remain a common agent class used for the management of pain in patients prior to spine surgery. Methods. A total of 583 patients were included. Self-reported daily opioid consumption was obtained preoperatively and converted into morphine equivalent amounts and opioid use was recorded at the 12-month postoperative time. Intraoperative and immediate postoperative opioid demand was calculated. Linear regression analyses for intraoperative and immediate postoperative opioid demand while logistic regression analyses for opioid independence at 12 months including relevant covariates such as depression and anxiety were performed. Results. The median preoperative morphine equivalent amount for the cohort was 8.75 mg, with 55% of patients reporting some degree of opioid use. Younger age, more invasive surgery, anxiety, and primary surgery were significantly associated with increased intraoperative opioid demand (P < 0.05). Younger age, anxiety, and greater preoperative opioid use were significantly associated with increased immediate postoperative opioid demand (P < 0.05). More invasive surgery, anxiety, revision surgery, and greater preoperative opioid use were significantly associated with a decreased incidence of opioid independence at 12 months postoperatively (P < 0.01). Conclusion. Greater preoperative opioid use prior to undergoing spine surgery predicts increased immediate postoperative opioid demand and decreased incidence of postoperative opioid independence. Psychiatric diagnoses in those using preoperative opioids were predictors of continued opioid use at 12 months. Patients may benefit from preoperative counseling that emphasizes minimizing opioid use prior to undergoing spine surgery. Level of Evidence: 2

Preoperative narcotic use and its relation to depression and anxiety in patients undergoing spine surgery.

Study Design. Prospective review of registry data at a single institution from October 2010 to June 2012. Objective. To assess whether the amount of preoperative narcotic use is associated with preoperative depression and anxiety in patients undergoing spine surgery for a structural lesion. Summary of Background Data. Previous work suggests that narcotic use and psychiatric comorbidities are significantly related. Among other psychological considerations, depression and anxiety may be associated with the amount of preoperative narcotic use in patients undergoing spine surgery. Methods. Five hundred eighty-three patients undergoing lumbar (60%), thoracolumbar (11%), or cervical spine (29%) were included. Self-reported preoperative narcotic consumption was obtained at the initial preoperative visit and converted to daily morphine equivalent amounts. Preoperative Zung Depression Scale (ZDS) and Modified Somatic Perception Questionnaire (MSPQ) scores were also obtained at the initial preoperative visit and recorded as measures of depression and anxiety, respectively. Resistant and robust bootstrapped multivariable linear regression analysis was performed to determine the association between ZDS and MSPQ scores and preoperative narcotics, controlling for clinically important covariates. Mann-Whitney U tests examined preoperative narcotic use in patients who were categorized as depressed (ZDS ≥ 33) or anxious (MSPQ ≥ 12). Results. Multivariable analysis controlling for age, sex, smoking status, preoperative employment status, and prior spinal surgery demonstrated that preoperative ZDS (P = 0.006), prior spine surgery (P = 0.007), and preoperative pain (0.014) were independent risk factors for preoperative narcotic use. Preoperative MSPQ (P = 0.083) was nearly a statistically significant risk factor. Patients who were categorized as depressed or anxious on the basis of ZDS and MSPQ scores also showed higher preoperative narcotic use than those who were not (P < 0.0001). Conclusion. Depression and anxiety as assessed by ZDS and MSPQ scores were significantly associated with increased preoperative narcotic use, underscoring the importance of thorough psychological and substance use evaluation in patients being evaluated for spine surgery. Level of Evidence: 2

Sterility of C-arm fluoroscopy during spinal surgery

Study Design. Prospective study evaluating the sterility of 25 C-arm drapes after their use during spine surgery. Objective. To use swab samples to evaluate the sterility of draped C-arms at the end of spine surgical cases and assess the integrity of the sterile technique. Summary of Background Data. Intraoperative fluoroscopy is used routinely in the operating room for a variety of spinal applications. Although the C-arm may help the surgeon assess spinal alignment and facilitate the placement of instrumentation, there are concerns that the C-arm may represent a potential source of contamination and increase the risk of developing a postoperative infection. Methods. This study included 25 surgical cases requiring a standard fluoroscopic C-arm that were performed by 2 spine surgeons. Sterile culture swabs were used to obtain samples from 5 defined locations on the C-arm drape after its use during the operation. The undraped technician’s console was sampled in each case as a positive control and an additional 25 C-arm drapes were swabbed immediately after they were applied to the C-arm unit in order to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates using a semiquantitative technique. Results. Contamination was noted on only 1 of 25 negative control drapes at a single location (4%). One hundred percent and 96% of the positive control swabs that were obtained from the negative controls and postoperative drapes exhibited growth, respectively. Although at least some degree of contamination was observed at all locations of the C-arm drape after surgery, the upper 2 sample sites demonstrated the greatest degree of contamination; the incidences of postoperative contamination were significantly greater for the top (56%, P < 0.000001) and upper front of the receiver (28%, P = 0.010) compared to the negative controls. In contrast, the lower front, receiver plate, and midportion of the C-arm were associated with lower rates of contamination (12%–20%). Conclusion. The upper portions of the C-arm clearly exhibited the greatest rates of contamination during spinal operations. This contamination most likely occurs when the undraped portions of the C-arm are rotated to acquire lateral images. As a result, we no longer consider the top portion of the C-arm drape to be sterile in these situations and we believe that avoiding contact with these areas may decrease the risks of intraoperative contamination and possibly postoperative infection as well.

Fibrinolysis is essential for fracture repair and prevention of heterotopic ossification.

Bone formation during fracture repair inevitably initiates within or around extravascular deposits of a fibrin-rich matrix. In addition to a central role in hemostasis, fibrin is thought to enhance bone repair by supporting inflammatory and mesenchymal progenitor egress into the zone of injury. However, given that a failure of efficient fibrin clearance can impede normal wound repair, the precise contribution of fibrin to bone fracture repair, whether supportive or detrimental, is unknown. Here, we employed mice with genetically and pharmacologically imposed deficits in the fibrin precursor fibrinogen and fibrin-degrading plasminogen to explore the hypothesis that fibrin is vital to the initiation of fracture repair, but impaired fibrin clearance results in derangements in bone fracture repair. In contrast to our hypothesis, fibrin was entirely dispensable for long-bone fracture repair, as healing fractures in fibrinogen-deficient mice were indistinguishable from those in control animals. However, failure to clear fibrin from the fracture site in plasminogen-deficient mice severely impaired fracture vascularization, precluded bone union, and resulted in robust heterotopic ossification. Pharmacological fibrinogen depletion in plasminogen-deficient animals restored a normal pattern of fracture repair and substantially limited heterotopic ossification. Fibrin is therefore not essential for fracture repair, but inefficient fibrinolysis decreases endochondral angiogenesis and ossification, thereby inhibiting fracture repair.

Analysis of single-incision versus dual-incision fasciotomy for tibial fractures with acute compartment syndrome.

Objectives: To analyze the rate of postoperative infection and nonunion after tibial fractures in patients treated for acute compartment syndrome (ACS) using (1) single-incision versus (2) dual-incision fasciotomy technique. Design: Retrospective. Setting: Level I trauma center. Patients: Review of all adult tibial fractures operatively treated (n = 2756) over a 12-year period identified 175 patients with concurrent ACS requiring fasciotomy. Of 60 patients treated with intramedullary nails, 36 patients had single-incision fasciotomy and 24 had dual-incision fasciotomy. Of 81 patients treated with plate fixation, 59 patients had single-incision fasciotomy and 22 had dual-incision fasciotomy. Intervention: Tibial fixation with fasciotomy for ACS. Main Outcome Measurements: Occurrence of postoperative infection and nonunion. Results: Both fasciotomy groups were similar across recorded patient and treatment characteristics. Need for skin graft was similar between fasciotomy groups. For patients treated with intramedullary nail (n = 60), 1 infection (2.8%) occurred in single-incision group versus 2 (8.3%) in dual-incision group (P = 0.558). Seven nonunions (19.4%) occurred in single-incision group versus 3 (12.5%) in dual-incision group (P = 0.726). For plate fixation patients (n = 81), 15 infections (25.4%) occurred with single-incision fasciotomy versus 5 infections (22.7%) with dual-incision fasciotomy (P = 1.000). Seven nonunions (11.9%) occurred with single-incision group versus 4 nonunions (18.2%) with dual-incision group (P = 0.479). Conclusions: This is the first study to compare a single-incision fasciotomy technique to a dual-incision technique in the setting of tibial fractures with ACS, with similar infection and nonunion rates with either technique. The choice of fasciotomy technique can be based on surgeon experience or patient condition as opposed to a suspected elevated infection or nonunion risk with either technique. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Microscope Sterility During Spine Surgery

Study Design. Prospective study. Objective. Assess the contamination rates of sterile microscope drapes after spine surgery. Summary of Background Data. The use of the operating microscope has become more prevalent in certain spine procedures, providing superior magnification, visualization, and illumination of the operative field. However, it may represent an additional source of bacterial contamination and increase the risk of developing a postoperative infection. Methods. This study included 25 surgical spine cases performed by a single spine surgeon that required the use of the operative microscope. Sterile culture swabs were used to obtain samples from 7 defined locations on the microscope drape after its use during the operation. The undraped technicians console was sampled in each case as a positive control, and an additional 25 microscope drapes were swabbed immediately after they were applied to the microscope to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates using a semiquantitative technique. Results. No growth was observed on any of the 25 negative control drapes. In contrast, 100% of preoperative and 96% of postoperative positive controls demonstrated obvious contamination. In the postoperative group, all 7 sites of evaluation were found to be contaminated with rates of 12% to 44%. Four of the 7 evaluated locations were found to have significant contamination rates compared with negative controls, including the shafts of the optic eyepieces on the main surgeon side (24%, P = 0.022), “forehead” portion on both the main surgeon (24%, P = 0.022) and assistant sides (28%, P = 0.010), and “overhead” portion of the drape (44%, P = 0.0002). Conclusion. Bacterial contamination of the operative microscope was found to be significant after spine surgery. Contamination was more common around the optic eyepieces, likely due to inadvertent touching of unsterile portions. Similarly, all regions above the eyepieces also have a propensity for contamination because of unknown contact with unsterile parts of the surgeon. Therefore, we believe that changing gloves after making adjustments to the optic eyepieces and avoid handling any portion of the drape above the eyepieces may decrease the risks of intraoperative contamination and possibly postoperative infection as well.