Effect of IV contrast on lumbar trabecular attenuation at routine abdominal CT: correlation with DXA and implications for opportunistic osteoporosis screening.

UNLABELLED: Osteoporosis remains under-diagnosed. Routine abdominal CT can provide opportunistic screening, but the effect of IV contrast is largely unknown. The overall performance for predicting osteoporosis was similar between enhanced and unenhanced scans. Therefore, both non-contrast and contrast-enhanced abdominal CT scans can be employed for opportunistic osteoporosis screening. INTRODUCTION: Osteoporosis is an important yet under-diagnosed public health concern. Lumbar attenuation measurement at routine abdominal CT can provide a simple opportunistic initial screen, but the effect of IV contrast has not been fully evaluated. METHODS: Mean trabecular CT attenuation values (in Hounsfield units, HU) at the L1 vertebral level were measured by oval region-of-interest (ROI) on both the unenhanced and IV-contrast-enhanced CT series in 157 adults (mean age, 62.0). All patients underwent correlative central DXA within 6 months of CT. Based on DXA BMD of the lumbar spine, femoral neck, and total proximal femur: osteoporosis, osteopenia, and normal BMD was present in 33, 77, and 47, respectively. Statistical analysis included Bland-Altman plots and receiver operating characteristic (ROC) curves. RESULTS: Mean difference (±SD) in L1 trabecular attenuation between enhanced and unenhanced CT series was +11.2 HU (±19.2) (95 % CI, 8.16-14.22 HU), an 8 % difference. Intra-patient variation was substantial, but no overall trend in the HU difference was seen according to underlying BMD. ROC area under the curve (AUC) for unenhanced and enhanced CT for diagnosing osteoporosis were similar at 0.818 and 0.830, respectively (p = 0.632). Thresholds for maintaining 90 % specificity for osteoporosis were 90 HU for unenhanced and 102 HU for enhanced CT. Thresholds for maintaining 90 % sensitivity for osteoporosis were 139 HU for unenhanced and 144 HU for enhanced CT. Similar diagnostic performance was seen for diagnosing low BMD (osteoporosis or osteopenia) using higher HU cut-offs. CONCLUSION: Contrast-enhanced CT shows an average increase of 11 HU over the unenhanced series for L1 trabecular attenuation. The overall performance for predicting osteoporosis is similar between the enhanced and unenhanced scans, thus either can be employed for initial opportunistic screening.

Sports and physical training injury hospitalizations in the army.

INTRODUCTION: Injuries are the leading health problem in the military services. Sports and physical training activities are an area in which a substantial number of injuries can occur. Although athletic injuries are not often investigated in military populations, the Armed Forces database provides a unique opportunity to investigate sports injuries. METHODS: An Army database of all hospital admissions for active duty Army personnel in the 1989-1994 period was used to study injuries resulting from sports and Army physical training. RESULTS: For the 6-year time period reviewed, there were 13,861 hospital admissions for injuries resulting from sports or Army physical training: 94% (13,020) of these admissions were men and 6% (841) were women. The rates of sports injuries were 38 and 18 per 10,000 person-years for men and women, respectively. Sports injuries accounted for an average of 29,435 lost duty days each year: Men lost an average of 13 days per injury and women lost an average of 11 days per injury. Acute musculoskeletal injuries in the categories of fractures, sprains/strains, and dislocations accounted for 82% of all injuries. The knee was the most often injured body area in both genders, with the anterior cruciate ligament (ACL) identified as the most frequently injured body part overall. The top seven injuries were virtually identical for men and women, with only slight variations in order. Although the rates of all hospitalized sports injuries were higher for men than women, women had a higher proportion of ACL injuries from basketball and softball, ankle fractures from softball and head injuries from basketball. For men, football and basketball contributed to the highest rates of injuries. The highest injury rates for women were from Army physical training and basketball. For both men and women, Army physical training was the leading cause of lumbosacral strains. CONCLUSIONS: Sports and Army physical training injuries account for a significant amount of lost duty time and impact military readiness.

Recurrent abdominal pain from abdominal adhesions in an endurance triathlete.

Abdominal adhesions have been described as developing postoperatively and as developing "spontaneously" in patients over 60 yr old. To our knowledge, abdominal adhesions have not been described as an etiology of recurrent abdominal pain in young endurance athletes, without prior history of abdominal surgery. We present a 28-yr-old endurance triathlete with recurrent abdominal pain in which multiple diagnostic imaging studies were unable to diagnose the etiology. Diagnostic laparoscopy revealed adhesions between the ascending colon and the anterior abdominal wall. Laparoscopic adhesiolysis was performed successfully and the athlete resumed his training several weeks post-laparoscopy without symptoms. One year later, the athlete remains pain free.

Abnormal eating behaviors in military women.

PURPOSE: The purpose of this study was to evaluate the prevalence of abnormal eating behaviors in women on active duty in the Army. METHODS: A total of 423 female soldiers from the general population on active duty volunteered to participate in this study. They completed the Eating Disorder Inventory (EDI) questionnaire. Each questionnaire was screened and any woman on active duty practicing abnormal eating behaviors (criteria set up by the authors) underwent an interview. A diagnosis, using DSM IV criteria, of one of the following was determined from the interview: 1) No eating disorder, (2) Anorexia nervosa, 3) Bulimia nervosa, 4) binge eating disorder, 5a) Eating disorder NOS, and 5b) Situational eating disorder. A situational eating disorder was defined as any abnormal eating behaviors consistent with an eating disorder NOS that was practiced intermittently and in response to external pressures associated with significant distress, such as military weigh-ins or army physical fitness testing (APFT). RESULTS: Of the 423 women on active duty who participated, 33.6% (N = 142) met the questionnaire screening criteria for being "at risk" for abnormal eating behaviors and underwent an interview. Of the 142 women interviewed, 33 (8%) women were diagnosed with an eating disorder. The women with eating disorders exercised, felt dissatisfied with their weight, and felt significantly more pressure about their weight than the women without eating disorders. In addition, they also had significantly greater scores on the Drive for Thinness (DT), Bulemia (B), and Body Dissatisfaction (BD) subscales, and the total EDI scores for both the 8 and 11 subscales. CONCLUSION: In the women on active duty in the Army studied, there was an 8% prevalence of eating disorders.

Deep water running: an effective non-weightbearing exercise for the maintenance of land-based running performance.

Deep water running (DWR) has become a well-recognized from of cardiovascular conditioning for injured athletes and has been used successfully to maintain running performance. DWR provides for decreased stress and weightbearing to injured tissue and joints, allows for maintenance of cardiovascular fitness and a training effect, and offers greater specificity of exercise in relation to running. During a 22-month period, 181 active duty Army soldiers, placed on temporary profiles for injuries that precluded them from their regular weightbearing physical fitness activities, participated in a DWR program. Injuries to the back, knee, and ankle were the most common reasons for referral to the program. This article reviews the physiological characteristics of DWR, specifics of DWR program design, DWR mechanics, and the advantages of DWR over other aerobic forms of exercise to maintain land running performance in military personnel on temporary non-weightbearing profiles.

Abnormal eating behaviors in female reserve officer training corps cadets.

The objective of this study was to evaluate the prevalence of abnormal eating behaviors in Reserve Officer Training Corps (ROTC) female cadets. A total of 310 female ROTC cadets participated in a prospective, cross-sectional study during summer training at Fort Lewis, Washington. All subjects completed the Eating Disorder Inventory and a supplemental questionnaire. Because of time constraints, clinical interviews were not administered. Of the 310 ROTC cadets, 20% met the screening criteria for being at risk for an eating disorder. The cadets at risk for eating disorders had significantly higher Drive for Thinness, Bulimia, and Body Dissatisfaction subscale scores and were more dissatisfied with their weight than cadets not at risk. There was no significant difference in reported ideal body weight and exercise intensity between the two groups. In the female ROTC cadet population evaluated, 20% practiced abnormal eating behaviors and were at risk for developing an eating disorder.

The female athlete triad: prevalence in military women.

The objective of this study was to define the prevalence of the female athlete triad, i.e., the simultaneous occurrence of disordered eating, amenorrhea, and osteoporosis, in military women. A total of 423 active duty female soldiers participated in a three-part prospective, cross-sectional study. Part 1 entailed completing the Eating Disorder Inventory and a clinical interview with those women "at risk" for an eating disorder. Part 2 consisted of a clinical evaluation and laboratory studies of any woman with menstrual irregularities. Part 3 evaluated the bone mineral density of all women meeting the inclusion criteria for parts 1 and 2 using dual-energy X-ray absorptiometry. Of the 423 active duty women who participated in the study, no subject exhibited the full female athlete triad. Thirty-three women (8%) had an eating disorder and 109 women (26%) were at risk for an eating disorder. Our results suggest that the female athlete triad is not a clinically significant problem for the Army.

Relationship between muscle abnormalities and symptom duration in lumbosacral radiculopathies.

A long held notion in the electrodiagnostic literature is that paraspinal muscles tend to show electromyographic abnormalities early on in a lumbosacral radiculopathy and that more distal muscles become abnormal later in the disease process. The purpose of this study was to determine whether paraspinal muscles and other major proximal and distal muscle abnormalities are related to lumbosacral radiculopathy symptom duration. A multivariate logit analysis of 139 patients (retrospectively identified) with electrodiagnostically confirmed lumbosacral radiculopathies was used to test these hypotheses. Maximum likelihood estimates showed no evidence of correlation between abnormal paraspinal muscles and symptom duration. Symptom duration was also insignificant for the remaining five lower limb muscles analyzed. We conclude that the probability of having electromyographic abnormalities is not related to symptom duration. A prospective study is needed to confirm these findings. Nonetheless, clinicians should use caution when interpreting electrodiagnostic findings based on symptom duration.

Cervical paraspinal muscle abnormalities and symptom duration: a multivariate analysis.

The purpose of this study was to determine whether paraspinal and other major proximal and distal muscle spontaneous activity (SA) is related to cervical radiculopathy (CR) symptom duration. A multivariate analysis of 124 (retrospectively identified) electrodiagnostically confirmed CRs was used to test these hypotheses. The results showed no evidence of correlation between SA and symptom duration for any of the upper limb muscles analyzed.

The relation between stress fractures and bone mineral density: evidence from active-duty Army women.

OBJECTIVE: To determine if bone mineral density (BMD) is associated with the probability of stress fractures in premenopausal women. DESIGN: Case-control study. SETTING: Large Army post, Fort Lewis, WA. PARTICIPANTS: Twenty-seven active duty Army women with documented stress fractures within the last 2 years and 158 female controls. METHODS AND MAIN RESULTS: All subjects were examined and interviewed. BMD of the femoral neck and posteroanterior lumbar spine (L2-L4) was measured using dual energy X-ray absorptiometry. Univariate comparisons revealed no significant differences in BMD of the femoral neck or lumbar spine between groups. Women with stress fractures had a significantly higher exercise intensity (428 vs 292 minutes per week, p<.05) and were more likely to be entry-level enlisted soldiers (63% vs. 44%, p<.05) than those without stress fractures. Multivariate analyses revealed a strong negative association between femoral neck BMD and the probability of stress fractures (lower BMD, higher risk). Exercise intensity and body mass index had a significant positive effect on BMD of the femoral neck and lumbar spine, yet both were associated with an increased probability of stress fractures. CONCLUSIONS: Femoral neck BMD was significantly associated with the probability of stress fractures. Optimal training programs should balance the beneficial indirect effect of increased exercise (through increased BMD) with its detrimental direct effect on stress fractures.

Effect of history and exam in predicting electrodiagnostic outcome among patients with suspected lumbosacral radiculopathy.

OBJECTIVE: To determine the extent to which the history and physical examination predict the outcome of the electrodiagnostic (EDX) evaluation in patients with suspected lumbosacral radiculopathy. DESIGN: Data for 170 subjects referred for low-back and lower limb symptoms were prospectively collected at five EDX laboratories. The sensitivity, specificity, positive and negative predictive values, and odds ratios were determined for symptoms and neurologic signs. RESULTS: Symptoms were not significantly associated with an EDX study or a lumbosacral radiculopathy. The physical examination was better at predicting that an EDX study would be abnormal in general than it was at predicting a lumbosacral radiculopathy in particular. Of those subjects with normal physical examinations, 15%-18% still had abnormal EDX findings. CONCLUSIONS: In a population of patients referred for an EDX study, the history and physical examination alone cannot reliably predict electrodiagnostic outcome.

Predicting electrodiagnostic outcome in patients with upper limb symptoms: are the history and physical examination helpful?

OBJECTIVE: To determine the effectiveness of medical history and physical examination in predicting electrodiagnostic outcome in patients with suspected cervical radiculopathy. METHODS: Data on 183 subjects prospectively collected at five different electrodiagnostic laboratories were analyzed (96 cervical radiculopathies, 45 normal studies, and 42 abnormal electrodiagnostic findings other than radiculopathy). The sensitivity, specificity, positive predictive value, negative predictive value, and odds ratios were determined for symptoms and neurologic signs. RESULTS: Symptoms of numbness, weakness, and tingling were associated with twice the probability of having abnormal electrodiagnostic study results in general, yet were not helpful in identifying a cervical radiculopathy. All single and combined physical examination components had poor sensitivities, with the exception of weakness, but much higher specificities. Patients with either weakness or reduced reflexes on physical examination were up to five times more likely to have abnormal electrodiagnostic findings. In subjects with any abnormal neurologic sign, the sensitivity improved to 84%, the positive predictive value was 79%, but the specificity was low (44%). Of those subjects with normal physical examination results, almost one half had an abnormal electrodiagnostic study result (negative predictive value 52%). CONCLUSIONS: In a population of patients with suspected cervical radiculopathy, medical history and physical examination are helpful yet not sufficient to predict the electrodiagnostic outcome.

Symptom duration and spontaneous activity in lumbosacral radiculopathy.

OBJECTIVES: A long-held notion in the electrodiagnostic literature is that paraspinal muscles tend to show spontaneous activity (fibrillations and positive sharp waves) on needle electromyography, early on in a lumbosacral radiculopathy, and that more distal muscles become abnormal later in the disease process. The purpose of this study was to determine whether paraspinal muscle and other major proximal and distal muscle spontaneous activity is related to a lumbosacral radiculopathy symptom duration. METHODS: A multicenter, prospective study that collected standard information on history, physical examination, and electrodiagnostic findings in patients with electrodiagnostically confirmed lumbosacral radiculopathies was undertaken. RESULTS: Multivariate probit analyses of 96 patients identified with a lumbosacral radiculopathy showed no evidence of correlation between spontaneous activity in the paraspinal muscles and symptom duration. Symptom duration was also nonsignificant in nine of the remaining ten lower limb muscles analyzed. CONCLUSION: These findings emphasize the limitations of using symptom duration when interpreting electrodiagnostic findings in lumbosacral radiculopathy.

Lumbosacral radiculopathy screen. Optimizing the number of muscles studies.

The literature is unclear as to which muscles and how many are required for a sensitive lumbosacral radiculopathy (LSR) screen. A retrospective study of 247 electrodiagnostically confirmed LSRs in 201 patients over a 3-yr period was conducted to determine how many muscles were required to identify a LSR. All LSRs showed abnormal spontaneous activity (positive waves or fibrillation potentials) in two or more muscles innervated by the same nerve root level but different peripheral nerves. All cases were categorized by radiculopathy level, and the most frequently abnormal individual muscles were combined into different muscle screens. The frequency with which each muscle screen identified a radiculopathy was the frequency with which one or more muscles in the screen displayed abnormal spontaneous activity divided by the total number of radiculopathies. The paraspinal muscles (PM) alone identified 88% of LSRs. Without PM, two muscle screens identified only 14-68%, three muscle screens identified 37-89% and four muscle screens identified 45-92%. Including PM, three muscle screens identified 86-94% of LSRs, four muscle screens identified 91-97% and five muscle screens yielded 94-98% identification. Seven to ten muscle screens resulted in minimal improvements in identifying a LSR with 98-99% identification. We conclude that five muscle LSR screens, including PM, are sufficient to identify LSRs while minimizing patient discomfort and examiner time.

Identifying lumbosacral radiculopathies: an optimal electromyographic screen.

OBJECTIVE: The objective of this study was to determine prospectively the optimal electromyographic screening examination of the lower limb that ensures identification of those lumbosacral radiculopathies that can be electrodiagnostically confirmed, yet minimizes the number of muscles studied. DESIGN: A prospective multicenter study was conducted from May 1996 to September 1997. Patients with suspected lumbosacral radiculopathy referred to participating electrodiagnostic laboratories were recruited and examined by needle electromyography using a standard set of muscles. Patients with electrodiagnostically confirmed lumbosacral radiculopathies were selected for analysis. Various muscle screens were tested against this group of patients with radiculopathies to determine the frequency with which each screen identified the patient with radiculopathy. RESULTS: There were 102 patients identified. When paraspinal muscles were one of the screening muscles, four-muscle screens identified 88-97% of the radiculopathies, five-muscle screens identified 94-98%, and six-muscle screens 98-100%. When paraspinal muscles were not part of the screen, identification rates were lower for all screens, and eight distal muscles were necessary to identify about 90% of the radiculopathies. CONCLUSIONS: Six-muscle screens with paraspinal muscles yielded consistently high identification rates. Studying additional muscles produced no improvements in identification.

Identification of cervical radiculopathies: optimizing the electromyographic screen.

OBJECTIVE: To determine the optimal electromyography screening examination of the upper limb that ensures detection of those cervical radiculopathies, which can be electrodiagnostically confirmed, yet minimizes the number of muscles studied. DESIGN: A prospective multicenter study was conducted from May 1996 to September 1997 at five institutions. Patients who were referred to participating electrodiagnostic laboratories with suspected cervical radiculopathy were recruited. A standard set of muscles were examined by needle electromyography. Patients with electrodiagnostically confirmed cervical radiculopathies, based on electromyography findings, were selected for analysis. Muscle screens were tested against this group to determine whether the screen identified the patients with radiculopathy. RESULTS: There were 101 patients with cervical radiculopathies representing all cervical root levels. When paraspinal muscles were one of the screening muscles, five muscle screens identified 90% to 98% of radiculopathies, six muscle screens identified 94% to 99%, and seven muscle screens identified 96% to 100%. When paraspinal muscles were not part of the screen, eight distal limb muscles recognized 92% to 95% of radiculopathies. CONCLUSION: This study demonstrated that six muscle screens including paraspinal muscles yielded consistently high identification rates. Studying additional muscles led to marginal increases in identification.

Cervical radiculopathies: relationship between symptom duration and spontaneous EMG activity.

The purpose of this multicenter study was to prospectively examine whether denervation in paraspinal muscles (PSM) and in other major proximal and distal muscles is related to symptom duration in cervical radiculopathies (CRs). Information was collected on 93 electrodiagnostically confirmed CRs using standardized history, physical examination, and electromyographic (EMG) screens. Multivariate, maximum-likelihood estimates showed no evidence of correlation between PSM spontaneous activity and symptom duration. Symptom duration was also nonsignificant in eight of the remaining nine upper limb muscles analyzed. We conclude that the probability of spontaneous activity is not related to symptom duration. Clinicians, therefore, should refrain from interpreting electrodiagnostic findings based upon duration of symptoms.