Opportunistic Use of CT Imaging for Osteoporosis Screening and Bone Density Assessment: A Qualitative Systematic Review.

BACKGROUND: The purpose of this study was to determine the clinical opportunities for the use of computed tomography (CT) imaging for inferring bone quality and to critically analyze the correlation between dual x-ray absorptiometry (DXA) and diagnostic CT as reported in the literature. METHODS: A systematic review of the MEDLINE database was performed in February 2016 using the PubMed interface. The inclusion criteria were English language, studies performed using living human subjects, studies pertaining to orthopaedics, use of conventional diagnostic CT scans, studies that measured cancellous bone, and studies that reported Hounsfield unit (HU) measurements directly rather than a computed bone mineral density. RESULTS: Thirty-seven studies that reported on a total of 9,109 patients were included. Of these, 10 studies correlated HU measurements of trabecular bone with DXA-based bone assessment. Reported correlation coefficients ranged between 0.399 and 0.891, and 5 of the studies reported appropriate threshold HU levels for diagnosing osteoporosis or osteopenia. CONCLUSIONS: Direct HU measurement from diagnostic CT scans has the potential to be used opportunistically for osteoporosis screening, but in its current state it is not ready for clinical implementation. There is a lack of exchangeability among different machines that limits its broad applicability. Future research efforts should focus on identifying thresholds at specific anatomic regions in high-risk patients in order to have the greatest impact on patients. However, using diagnostic CT to infer region-specific osteoporosis could be extraordinarily valuable to orthopaedic surgeons and primary care physicians, and merits further research.

Assessment of Vertebral Curves Using the Manual Post-It Technique.

STUDY DESIGN: A prospective study of a new technique. OBJECTIVE: The aims of this study were to report a manual technique for measuring vertebral curves on digital spine radiographs, and to assess the agreement of this technique with that of digital software for measuring vertebral curves. SUMMARY OF BACKGROUND DATA: Modern picture archiving and communication systems (PACS) typically include software for evaluating radiographic measurements. However, in the outpatient spine setting, patients may present with radiographs stored on a physical disc, which may not include software for measuring vertebral curves. Certain smartphone applications may be used to determine curve magnitude; however, the need exists for an accurate manual technique to measure vertebral curves on digital radiographs in the absence of available analytic software or smartphone technology. METHODS: We prospectively reviewed anteroposterior and lateral spine radiographs of 24 spinal deformity patients. Two independent observers measured Cobb angles for: (1) the major coronal curve; (2) the thoracic kyphosis (T2-T12); and (3) the lumbar lordosis (T12-S1). Measurements were made: (1) digitally using our institution's PACS; and (2) by a manual technique, which involves placement of an adhesive Post-It note directly on the computer screen, transcribing the angle onto the Post-It note with a pencil, and measuring the angle with a handheld goniometer. Intraclass correlation coefficients (ICCs) were calculated to determine the agreement between the 2 methods. RESULTS: For both observers, the agreement between the digital PACS and manual Post-It techniques was graded as excellent for both coronal and sagittal plane curves (all ICCs>0.9). Interobserver reliability between the 2 observers was also graded as excellent for both the PACS and Post-It techniques (all ICCs>0.9). CONCLUSIONS: The Post-It technique for measuring Cobb angles demonstrated excellent agreement with the PACS system in our series of spinal deformity patients. Curves on digital radiographs can be accurately measured using a convenient manual technique.

Simple Assessment of Global Bone Density and Osteoporosis Screening Using Standard Radiographs of the Hand.

PURPOSE: Osteoporosis and fragility fractures have consequences both at the individual level and to the overall health care system. Although dual-energy x-ray absorptiometry (DXA) is the reference standard for assessing bone mineral density (BMD), other, simpler tools may be able to screen bone quality provisionally and signal the need for intervention. We hypothesized that the second metacarpal cortical percentage (2MCP) calculated from standard radiographs of the hand or wrist would correlate with hip BMD derived from DXA and could provide a simple screening tool for osteoporosis. METHODS: Two hundred patients who had hand or wrist radiographs and hip DXA scans within 1 year of each other were included in this series. Mid-diaphyseal 2MCP was calculated as the ratio of the cortical diameter to the total diameter. We assessed the correlation between 2MCP and total hip BMD. Subjects were stratified into normal, osteopenic, and osteoporotic cohorts based on hip t scores, and thresholds were identified to optimize screening sensitivity and specificity. RESULTS: Second metacarpal cortical percentage correlated significantly with BMD and t scores from the hip. A 2MCP threshold of less than 60% optimized sensitivity (88%) and specificity (60%) for discerning osteopenic subjects from normal subjects, whereas a threshold of less than 50% optimized sensitivity (100%) and specificity (91%) for differentiating osteoporotic from normal subjects. CONCLUSIONS: By demonstrating that global BMD may be assessed from 2MCP, these data suggest that radiographs of the hand and wrist may have a role in accurately screening for osteopenia and osteoporosis. This simple investigation, which is already used ubiquitously for patients with hand or wrist problems, may identify patients at risk for fragility fractures and allow for appropriate referral or treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

The epidemiology of reoperation after flexor pulley reconstruction.

PURPOSE: We used a statewide database to determine the incidence of pulley reconstruction and to evaluate the influence of demographics on reoperation. We hypothesized that age, insurance status, and concomitant nerve or tendon procedure would influence the likelihood of reoperation. METHODS: We used the Statewide Planning and Research Cooperative System ambulatory surgery database from New York, which represents all outpatient surgery in the state. Patients who had flexor pulley reconstruction from 1998 to 2009 were identified using Current Procedural Terminology 4 codes. Subsequent surgery records for these patients were identified through 2010, allowing at least 1 year follow-up. Concomitant nerve procedure and flexor tendon repair/reconstruction were identified. The type and timing of subsequent procedures, including tenolysis and repeat pulley reconstruction, were recorded. Univariate statistics were calculated to compare age, sex, and payer type between patients with and without reoperation. A multivariable, logistic regression model was used to evaluate the association of the demographics with the chances of having reoperation. RESULTS: There were 623 patients who had flexor pulley reconstruction from 1998 to 2009. The incidence of pulley reconstruction was 0.27 per 100,000 persons, with an annual frequency of 52 procedures. There were 39 (6%) reoperations. There was no difference in age, concomitant nerve or tendon repair, or workers' compensation between patients with and without reoperation. Regression modeling showed a higher likelihood among men of having reoperation. CONCLUSIONS: Flexor pulley reconstructions are rare. One-quarter of surgeons performed only one flexor pulley reconstruction over a 12-year period. The 6% reoperation rate is similar to our previous findings for flexor tendon repair using similar methodology. Our report provides information that may be useful in counseling patients.