Guillermo F. Carrera

Excessive retroversion of the glenoid cavity. A cause of non-traumatic posterior instability of the shoulder.

Seventeen shoulders in ten adolescents were evaluated for non-traumatic posterior instability. Each patient had significant disability in throwing a ball, swimming, arm-blocking in football, and bench-pressing weights. Each patient had excessive retroversion of the glenoid. Five shoulders had a posterior opening-wedge osteotomy of the scapular neck to correct the excessive retroversion of the glenoid cavity. Acromial bone was used as graft material in the first four shoulders. Three shoulders lost some correction but only one required revision, which was done using cortical iliac bone as a graft and screw fixation. This technique was used primarily in the fifth shoulder. Excessive retroversion of the glenoid cavity is a developmental deformity and is considered the primary etiology of posterior instability of the shoulder. The posterior opening-wedge osteotomy of the scapular neck corrects the defect and the instability.

Prevalence of the Female Athlete Triad in High School Athletes and Sedentary Students

Objective:To determine the prevalence of the female athlete triad (low energy availability, menstrual dysfunction, and low bone mineral density) in high school varsity athletes in a variety of sports compared with sedentary students/control subjects. Design:Prospective study. Setting:Academic medical center in the Midwest. Participants:Eighty varsity athletes and 80 sedentary students/control subjects volunteered for this study. Intervention:Subjects completed questionnaires, had their blood drawn, and underwent bone mineral density testing. Main Outcome Measures:Each participant completed screening questionnaires assessing eating behavior, menstrual status, and physical activity. Each subject completed a 3-day food diary. Serum hormonal, thyroid-stimulating hormone, and prolactin levels were determined. Bone mineral density and body composition were measured by dual-energy x-ray absorptiometry. Results:Low energy availability was present in similar numbers of athletes (36%) and sedentary/control subjects (39%; P = 0.74). Athletes had more menstrual abnormalities (54%) compared with sedentary students/control subjects (21%) (P < 0.001). Dual-energy x-ray absorptiometry revealed that 16% of the athletes and 30% of the sedentary/control subjects had low bone mineral density (P = 0.03). Risk factors for reduced bone mineral density include sedentary control student, low body mass index, and increased caffeine consumption. Conclusions:A substantial number of high school athletes (78%) and a surprising number of sedentary students (65%) have 1 or more components of the triad. Given the high prevalence of triad characteristics in both groups, education in the formative elementary school years has the potential to prevent several of the components in both groups, therefore improving health and averting long-term complications.

Hindfoot Coronal Alignment: A Modified Radiographic Method

Accurate clinical evaluation of the alignment of the calcaneus relative to the tibia in the coronal plane is essential in the evaluation and treatment of hindfoot pathologic condition. Previously described radiographic views of the foot and ankle do not demonstrate the true coronal alignment of the calcaneus relative to the tibia. Some of these views impose on the patient an unnatural posture that itself changes hindfoot alignment, whereas other methods distort the coronal alignment by the angle of the x-ray beam. Our purpose was to develop a modified radiographic view and measurement method for determining an angular measurement of hindfoot coronal alignment based on a cadaver study of the radiographic characteristics of the calcaneus and motion analysis of standing subjects. The view was obtained by having the subject stand on a piece of cardboard to create a foot template. The template was then positioned so that each foot was x-rayed perpendicular to the cassette while still maintaining the natural base of support. A method using multiple ellipses was developed to determine more accurately the coronal axis of the posterior calcaneus. A study using cadavers was performed in which radio-opaque markers were placed on multiple bony landmarks on the calcaneus. The tibia was held fixed in a vertical position, and the foot was x-rayed using the above techniques in different degrees of rotation without changing the relation of the calcaneus to the tibia. The radiographs of the modified Cobey and our view were examined to verify which markers were visible at different angles of rotation and how the hindfoot alignment measurements changed with foot rotation. To define further the differences between the views, an analysis of postural stability was conducted while the subjects were standing with the feet in the positions for imaging both the Buck modification of the Cobey view and our hindfoot alignment view. The combined results of the cadaver, radiographic measurement, and postural stability segments of the study reveal that this coronal hindfoot alignment view and measurement method is reproducible, more closely measures “true” coronal hindfoot alignment, and is more clinically applicable because the alignment is measured while the patient is standing with a normal angle and base of stance. The modified radiographic measurement method relies on posterior calcaneal anatomic landmarks, is less affected by rotation of the foot and ankle, and is reproducible between observers.

Detection of osteomyelitis in the neuropathic foot: nuclear medicine, MRI and conventional radiography.

The diagnostic efficacy of (1) combined three-phase bone scintigraphy and In-111 labeled WBC scintigraphy (Bone/WBC), (2) MRI, and (3) conventional radiography in detecting osteomyelitis of the neuropathic foot was compared. Conventional radiography was comparable to MRI for detection of osteomyelitis. MRI best depicted the presence of osteomyelitis in the forefoot. Particularly in the setting of Charcot joints, Bone/WBC was more specific than conventional radiography or MRI.

The sacroiliac joints: anatomic, plain roentgenographic, and computed tomographic analysis.

Due to its unique bicompartmental anatomy and spatial configuration, the sacroiliac joint can be more accurately defined by computed tomography (CT) than conventional radiography. Using a tilted gantry and paraaxial scanning technique, the synovial portion of the joint is oriented vertically on the CT image, while the ligamentous portion is oriented oblique-horizontally. The tilted CT gantry technique allows full ventral-dorsal imaging of the synovial portion of the sacroiliac joint. We have found the accuracy of CT to be superior to conventional radiography in the detection of early erosive sacroiliitis and joint space narrowing. In all patients with discrepancy between the two radiologic techniques, the changes were either only demonstrated or better demonstrated by CT than conventional radiography.

Is There an Association between Athletic Amenorrhea and Endothelial Cell Dysfunction

PURPOSE To test the hypothesis that young females with athletic amenorrhea and oligomenorrhea show signs of early cardiovascular disease manifested by decreased endothelium-dependent dilation of the brachial artery. METHODS Ten women with athletic amenorrhea (mean +/- SE, age 21.9 +/- 1.2 yr), 11 with oligomenorrhea (age 20.8 +/- 1.1 yr), and 11 age-matched controls (age 20.2 +/- 1.1 yr) were studied. Study subjects were amenorrheic an average of 2.3 (range 0.6-5) yr and oligomenorrheic an average of 6.2 yr. All ran a minimum of 25 miles.wk. They were nonpregnant and free of metabolic disease. Brachial artery flow-mediated dilation (endothelium-dependent) was measured with a noninvasive ultrasound technique in each group. RESULTS Endothelium-dependent brachial artery dilation was reduced in the amenorrheic group (1.08 +/- 0.91%) compared with oligomenorrheic (6.44 +/- 1.3%; P< 0.05) and eumenorrheic (6.38 +/- 1.4%; P< 0.05) groups. CONCLUSION Athletic amenorrhea is associated with reduced endothelium-dependent dilation of the brachial artery. This may predispose to accelerated development of cardiovascular disease.

Chronic capitolunate instability.

Twelve patients, twelve to thirty-two years old, were evaluated for complaints of chronic vague pain, weakness, and clicking in the wrist that had followed a significant but remote dorsiflexion injury to the wrist. Although a standard orthopaedic examination and plain roentgenograms of the carpus were unremarkable, a dorsal-displacement stress test done under fluoroscopic control with the radius fixed showed dorsal subluxation of the capitate out of the cup of the lunate, accompanied by a marked feeling of apprehension by the patient. This was also associated with a painful snap or click due to a sudden dorsal attitude and ulnar shift of the lunate, best elicited with the wrist in slight ulnar deviation. We believe that this condition is due to attenuation of the radiocapitate ligament resulting from prior trauma. Eleven patients were operated on. The volar radiocapitate ligament was tightened by tethering its central portion to the radiotriquetral ligament, partially obliterating the space of Poirier. Slight extension of the wrist was lost by this procedure, but the capitate could no longer be passively displaced and the lunate became stable. Using both objective and subjective criteria, six patients had an excellent result; three, good; one, fair; and one, poor. There was an average final loss of 15 degrees of extension and 19 degrees of flexion of the wrist. The average length of follow-up was four years and four months (range, twenty-four to 109 months). We concluded that insufficiency of the radiocapitate ligament after trauma to the wrist is one cause of chronic symptomatic capitolunate instability. Shortening of the radiocapitate ligament is recommended to stabilize the lunate and capitate.

Listeriosis in immunosuppressed patients: A cluster of eight cases

Bactermia due to listeria monocytogenes developed in eight patients who were receiving immunosuppresive medications during a 15 month period at one hospital. Seven survived. Meningitis was documented in only the four who received kidney transplants. Their neurologic signs were minimal, indicating a need to treat any immunosuppressed patient with Listeria bacteremia for meningitis. During this period the incidence of Listeria bactermia in immunosuppressed patients greatly exceeded that previously observed in this hospital or reported elsewhere, but the incidence of infection with other opportunistic agents was not increased. As with previously decreased listeria outbreaks in nonimmunosuppressed patients, no source or mechanism of spread could be identified. Thus, disease due to L. monocytogenes may occur focally among immunosuppressed populations, a pattern which also appears to be emerging for other opportunistic agents. A patients exposure to different opportunistic agents may be as important as the kind of immunosuppressive therapy he recieves in determining which opportunistic infection he will acquire or even whether any infection will occur.

The os trigonum syndrome: use of bone scan in the diagnosis.

The os trigonum is an accessory bone of the foot found in 7% of the normal adult population. It is located at the posterolateral projection of the talus, and can occasionally give rise to symptoms of acute and chronic unexplained ankle pain. We report three patients, one with acute fracture and two with chronic ankle symptoms. Technetium 99 methylene diphosphonate showed intense focal uptake at the posterior talus pointing to the os trigonum as the site of symptoms. It was excised in two patients with complete relief. The third went on to develop an asymptomatic nonunion. We recommend bone scanning as a procedure that is helpful in delineating obscure pain in the ankle that may be due to chronic irritative nonunion of the os trigonum.

The Choledochocele: Correlation of Radiological, Clinical and Pathological Findings

Two cases of choledochocele are presented and 14 cases in the literature reviewed. Choledochocele is defined as a herniation of the common bile duct into the duodenum. This entity is distinguishable radiographically from duodenal diverticulum and duodenal duplication cyst by filling during cholangiography but not during upper gastrointestinal series. The duodenal diverticulum fills on upper gastrointestinal series but not on cholangiography. The duplication cyst will not fill with either method.