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Gary M Kiebzak

Publications and source records attributed to Gary M Kiebzak.

17 recordsLinked to original sources

Skeletal sites for osteoporosis diagnosis: the 2005 ISCD Official Positions.

The International Society for Clinical Densitometry (ISCD) has developed Official Positions to assist healthcare providers in addressing some of the issues inherent with the use of bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry (DXA) to diagnose osteoporosis, apply World Health Organization (WHO) T-score classifications, and monitor BMD changes over time. Differences exist, however, between the ISCD Official Position statement and that of the International Osteoporosis Foundation with respect to WHO criteria for skeletal sites. Consequently, a subcommittee of the ISCD was directed to address the application of the WHO classifications to specific skeletal sites and regions of interest. In 2005, the ISCD Position Development Conference reviewed the findings and prepared Official Positions, which address whether or not: (1) the lowest T-score of the total proximal femur, femoral neck, trochanter, and spine should continue to be used for diagnosis; (2) the WHO classification may be applied to a single vertebral body T-score; and (3) the ISCD should endorse the use of the National Health and Nutrition Examination Survey database for proximal femur T-score derivation. The resulting ISCD Official Positions, with their corresponding rationales and evidence are provided here, as well as questions that will need to be addressed in the future.

Absorptiometry, Photon↗

Effect of calcium tablets on interpretation of lumbar spine DXA scans.

Undissolved calcium (Ca) tablets in the gastrointestinal tract at the time of a dual-energy X-ray absorptiometry (DXA) scan could conceivably affect the accuracy of the lumbar spine bone mineral density (BMD) determination. We studied phantoms and volunteers to determine the effect of Ca tablets overlying bone, Ca tablets in the soft-tissue field, and Ca tablets overlapping both bone and soft tissue. For L1-4, a 500-mg Ca tablet taped to the phantom surface or the skin of volunteers resulted in <or=2.2% mean increase in measured BMD (less than the lumbar spine least significant change), changing the T-score for L1-4 very little. However, an overlying Ca tablet had a substantial effect on BMD of a single vertebral body. Greater effects were seen with higher amounts of tablet Ca and with lower BMD, resulting in as much as a 12.6% mean increase in single vertebral BMD in the in vivo series. Recent versions of DXA software successfully identified tablets in the soft-tissue field as artifact and eliminated the tablet pixels from the analysis. However, tablets overlapping bone and soft tissue necessitated operator intervention to either exclude the affected vertebral body or adjust edges by mapping the tablet as artifact and/or neutral field. A paraffin-coated Ca tablet swallowed by a volunteer was tracked serially by DXA during gastrointestinal transit. Similar effects were seen as with the phantom and volunteer studies using external tablets; there was little effect of the Ca tablet on L1-4 BMD either with the tablet overlying bone or in the soft-tissue field. We conclude that undissolved Ca tablets introduce small artifacts on L1-L4 BMD insufficient to alter diagnostic categorization of patients. However, if only two or three vertebral levels are available, misclassification of the patients may occur due to tablet artifact. The precision of monitoring BMD over time could also be adversely affected by tablet artifact if a tablet was directly overlying bone and undetected, especially with smaller regions of interest and with lower baseline BMD.

Absorptiometry, Photon↗

Relationship among MRTA, DXA, and QUS revisited.

Inexpensive, commercially produced devices that directly measure bone strength in vivo are not currently available. Mechanical response tissue analysis (MRTA), a unique prototype device, is an in vivo vibrational test that measures transverse bending stiffness (a measure of whole bone strength expressed as the product of estimated Young's modulus of elasticity and cross-sectional moment of inertia, EI, Nm2) at ulna midshaft. We compared speed of sound (SOS; [m/s]) in ulna cortical bone using a commercially available axial transmission quantitative ultrasound (QUS) device with EI using MRTA. Dual-energy X-ray absorptiometry (DXA) was used to provide an estimate of ulna size (cm2), bone mineral content (BMC; [g/cm]) and areal bone mineral density (BMD; [g/cm2]). The objective of the study was to determine if ulna SOS--alone or in combination with BMD from DXA--was correlated with ulna EI, thus becoming a surrogate measure of transverse bending stiffness, and thus whole bone strength. Data were collected from 138 female volunteers (18-86 yr). EI and SOS were significantly correlated, r = +0.218, p = 0.01, but r2 was very low, 4.8%. SOS and total ulna BMD were combined to estimate elastic modulus, which correlated with EI, r = +0.377, p < 0.0001; however, the correlation was not significantly better than with SOS alone. We conclude that axial transmission QUS is not a strong surrogate in vivo technique for estimating transverse bending stiffness.

Absorptiometry, Photon↗

Recalculation of the NHANES database SD improves T-score agreement and reduces osteoporosis prevalence.

UNLABELLED: In attempt to improve diagnostic agreement between manufacturers, a recent software update incorporated NHANES III data in GE Lunar densitometers. As a result, the femur neck and trochanter T-scores were lowered, and osteoporosis prevalence was increased. Use of a recalculated young-normal SD for the GE Lunar-adjusted NHANES III database improved diagnostic agreement and is recommended. INTRODUCTION: Use of manufacturer-specific normative databases for T-score derivation leads to discordance in T-score values and differences in diagnostic classification. To address this issue, the International Committee for Standards in Bone Measurement (ICSBM) recommended the NHANES III database for femur T-score derivation. Acquired on Hologic (Hol) instruments, this database requires conversion equations for application to other DXA systems. NHANES III total femur (TF) conversions for GE Lunar (GE) have previously been available, and femoral neck (FN) and trochanter (TR) equations were reported recently. Per the ICSBM recommendation, GE Lunar incorporated these values into their female database. This should produce T-score and diagnostic agreement between Hol and GE instruments; however, this has not been evaluated. MATERIALS AND METHODS: We compared GE femur scans in 115 postmenopausal women using software before and after the NHANES III software update. Subsequently, T-scores derived from femur scans obtained on GE and Hol densitometers were compared in a different group of 89 postmenopausal women. RESULTS: The NHANES III software update had no effect on measured BMD (g/cm2) at any femur region. However, because of changes in values used for T-score calculation (increase in the mean young-normal BMD at the FN and TR and a reduction in SD at the TR), the T-scores were lower (mean, 0.48 and 0.68, respectively) at the FN and TR using post-NHANES III software. Consequently, this update increased femur osteoporosis prevalence in these 115 women from 7.8% to 18.3%. Comparison of GE with Hol total proximal femur T-scores revealed a minimal difference (<0.1) and equal diagnoses of osteoporosis. FN and TR differences were larger, with mean GE T-scores lower than Hol (p < 0.001) by 0.17 and 0.50, respectively, thereby introducing osteoporosis diagnostic disagreement (13 [GE] versus 9 [Hol]). Our evaluation suggested that this disparity resulted from direct application of published NHANES III SDs at the FN and TR. As such, we applied the conversion formulae to the NHANES III published Hologic data and found the FN and TR SDs were greater than assumed by GE. Using our recalculated SD to derive T-scores reduced the mean GE/Hol T-score difference to 0.03 at the FN and 0.32 at the TR and resolved osteoporosis diagnostic disagreement. CONCLUSION: The GE NHANES III software update leads to lower FN and TR T-scores than obtained with Hol or prior GE software. Recalculation of the young-normal SD reduces this difference and is recommended. Clinicians are advised to avoid using the TR for diagnosis or, at a minimum, use caution when making treatment decisions based solely on T-score at this site.

Absorptiometry, Photon↗

Impact of using the ultradistal radius region of interest on diagnostic classification.

World Health Organization (WHO) criteria using T-scores for classifying patients as normal, osteopenic, or osteoporotic are based on bone mineral density (BMD, g/cm2) of the lumbar spine and hip and bone mineral content (BMC) (BMC, g) at the distal and midradius. There is no consensus on whether other forearm regions of interest (ROIs) can be used with the WHO criteria. Because the ultradistal radius region of interest (UDR) has a greater ratio of trabecular to cortical bone than midshaft portions of the radius, it is possible that more patients would be classified as osteoporotic if the UDR is measured. The objective of this study was to determine the prevalence of osteoporosis when using T-scores from the UDR in addition to PA lumbar spine, proximal femur (hip), and the radius 33% ROI. Retrospective data were obtained from three centers with differing patient demographics, thus reducing bias as a result of patient characteristics. Data were used only from patients who had a spine, hip, and forearm scan on the same day. Central dual-energy X-ray absorptiometry (DXA) systems included a GE Lunar DPX-L, DPX IQ, and Prodigy and a Hologic Delphi. Hologic data were for the ultradistal radius + ulna ROI (UDRU). Diagnostic classification (using the WHO T-score criteria) was made excluding and including the UDR and UDRU T-scores, in addition to lumbar spine (L2-L4 or L1-L4), hip (femoral neck, greater trochanter, or total), and the radius 33% ROI. The lowest T-score from any ROI determined the classification. For all GE Lunar patients (n = 409 women; age range: 20-96 yr), the distribution of normal, osteopenic, osteoporotic not using the UDR was 94 (23%), 170 (42%), and 145 (36%), respectively. The distribution when using the UDR was 67 (16%), 137 (33%), and 205 (50%), respectively. The difference in the ratio of normal + osteopenic versus osteoporotic when excluding and including the UDR T-scores was significant (p < 0.0001; two-tailed Fisher's exact test). For all Hologic patients (n = 153 women; age range: 44-93 yr), the distributions were 32 (21%), 66 (43%), and 55 (36%) not using and 31 (20%), 64 (42%), and 58 (38%), respectively, using the UDRU (not statistically significantly different). The group mean T-scores were lowest for the UDR compared to the spine and hip with GE Lunar but not Hologic patients.

Absorptiometry, Photon↗

Relationship between length of stay and dislocation rate after total hip arthroplasty.

The purpose of this study was to determine if decreased postoperative inpatient time (length of stay; LOS) after total hip arthroplasty (THA) was correlated with an increase in the dislocation rate after discharge. Reduced access to physical therapy, nursing reinforcement of dislocation precautions, and medical supervision could lead to a higher rate of adverse behaviors (such as inappropriate flexion and rotation) and accidents that might have otherwise been avoided in the initial 3 -months after surgery. We examined records from 850 patients (2 surgeons) who underwent primary THA from 1993 to 1998. LOS had progressively decreased over the 4 years since implementation of a clinical pathway (CP) in late 1993. The average LOS in 1992 was 6.6 days and was lowest in 1998 at 3.9 days. The dislocation rate before the CP was 0.5%. The dislocation rate increased significantly to 3.9% after implementation of the CP (P =.015). Use of the CP offers numerous advantages but is associated with a higher dislocation rate.

Arthroplasty, Replacement, Hip↗

Recovery of self-reported functional capacity after coronary artery bypass surgery.

STUDY OBJECTIVES: This study was conducted to determine the effects of age, gender, comorbid conditions, and exercise on the recovery of self-reported functional capacity after coronary artery surgery, and to identify predictors of 1-year functional capacity. PATIENTS: One hundred ninety-eight patients undergoing coronary artery bypass graft surgery. MEASUREMENTS AND RESULTS: Self-reported functional capacity was evaluated before surgery, and 3 months and 1 year postoperatively using the Veterans Specific Activity Questionnaire (VSAQ). Patients were classified into groups based on age, gender, comorbid conditions, and postoperative exercise. Repeated-measures analysis of variance was used to determine if groups differed with respect to functional capacity recovery and multiple linear regression was used to identify predictors of 1-year VSAQ score. A significant time by age interaction was found (p = 0.0001), with a more protracted recovery for older patients. There were significant group effects for gender (p = 0.0001), and presence of comorbid conditions (p = 0.0009); however, there were no time/group interactions for these variables. A significant group effect was found for postoperative exercise (p = 0.0001), with a trend toward group/time interaction (p = 0.096). Predictors of 1-year functional capacity were VSAQ score in the year prior to surgery and performance of regular aerobic exercise in the postoperative period. CONCLUSIONS: This study suggests that older patients attain good self-reported functional outcomes after surgery; however, the time course for recovery is more protracted than for younger patients. Functional capacity in the year prior to surgery and postoperative exercise are key predictors of 1-year functional capacity.

Activities of Daily Living↗

Transpedicular decompression and pedicle subtraction osteotomy (eggshell procedure): a retrospective review of 59 patients.

STUDY DESIGN: Outcomes of transpedicular decompression and/or osteotomy were analyzed retrospectively. OBJECTIVES: To determine the effectiveness of decompression and correction, fusion stability, procedural safety, neurologic outcome, complication rates, and overall patient outcomes. SUMMARY OF BACKGROUND INFORMATION: The "eggshell" procedure is reserved for complex reconstructive problems in the treatment of acute trauma, deformity, tumor, or infection. The technique encompasses a range of procedures from simple transpedicular decompression and posterior fusion to more complex procedures, including transpedicular vertebrectomy and strut-grafting or pedicle subtraction (closing wedge) osteotomy with posterolateral fusion. These procedures are completed through a single posterior midline incision, with anterior spinal canal decompression a transpedicular approach, accompanied by a posterior or posterolateral fusion and internal fixation. METHODS: From 1990 to 1998, 59 "eggshell" procedures were performed for 37 deformity cases and 22 tumor or infection cases. Forty-two patients had a minimum 2-year follow-up, averaging 4.5 +/- 2.5 years. Thirty-six patients were available for patient interview, physical examination, and radiographic analysis. Outcome data were collected using SF-36 and SRS instruments. RESULTS: No patients worsened neurologically, and all incomplete spinal cord injuries improved. All patients achieved solid fusion radiographically. Correction with osteotomy averaged 26 degrees. Systemic complication rates were low with a pulmonary complication rate of 5%. Blood loss averaged 2342 mL. Overall patient outcomes were below population norms, but patient satisfaction was very high. CONCLUSION: Overall, the results suggest that the "eggshell" procedure is a reliable and safe technique to achieve anterior decompression of the spinal canal and posterior stabilization through a single approach.

Adolescent↗

Undertreatment of osteoporosis in men with hip fracture.

BACKGROUND: Women are not aggressively treated for osteoporosis after hip fracture; the treatment status of men with hip fracture has not been extensively studied. OBJECTIVE: To evaluate the outcome and treatment status of men with hip fracture. METHODS: Data from medical records were obtained for 363 patients (110 men and 253 women) aged 50 years and older with atraumatic (low-energy) hip fracture who were admitted to St Luke's Episcopal Hospital between January 1, 1996, and December 31, 2000. Surveys were mailed to surviving patients. Main outcome variables were osteoporosis treatments (antiresorptive or calcium and vitamin D) at hospital discharge, current osteoporosis treatments at 1- to 5-year follow-up, bone mineral density testing, mortality, current disability, and living arrangements (home or institution). RESULTS: The mean age for men was 80 years vs 81 years for women. Most fractures (89% for men and 93% for women) resulted from falls from a standing height. At hospital discharge, 4.5% of men (n = 5) had treatment of any kind for osteoporosis, compared with 27% of women (n = 69) (P<.001). The 12-month mortality was 32% in men, compared with 17% in women (P =.003). Surveys were usable from 168 (87%) of 194 survivors. At 1- to 5-year follow-up, 27% (12/44) of men were taking treatment of any kind for osteoporosis, compared with 71% (88/124) of women (P<.001). Of those treated, 67% (8/12) of men and 32% (28/88) of women were taking calcium and vitamin D only. At 1- to 5-year follow-up, 11% of men had a bone mineral density measurement, compared with 27% of women. After hospital discharge, the number of men and women who required wheelchairs, walkers, and canes and who lived in institutions increased significantly. CONCLUSIONS: The burden of hip fracture is illustrated by the high incidence of postfracture disability and the high mortality rate in both men and women. Nevertheless, few men receive antiresorptive treatment.

Aged↗

Distal tarsal tunnel release with partial plantar fasciotomy for chronic heel pain: an outcome analysis.

This study evaluated the effectiveness of distal tarsal tunnel release with a partial plantar fasciotomy for chronic subcalcaneal pain syndrome in patients who failed nonoperative management through a retrospective review of all patients undergoing this procedure between 1994 and 1999. Distal tarsal tunnel release and a partial plantar fasciotomy were offered only to those patients with disabling heel pain and were performed under general anesthesia or ankle block. Seventy-five patients (80 heels), averaging 20 months of nonoperative treatment, were identified (group I). Postoperative outcome questionnaires (SF-36 and Foot Function Index [FFI]) were sent to these patients and 44 (46 heels) responded (group II). In group I, 88% of patients had a good to excellent result. Many continued with mild to moderate residual symptoms, which typically did not limit their activity. In group II, 91% of patients were somewhat to very satisfied with their outcome. Visual analogue scale scores for pain were reduced by a mean of 55. SF-36 scores, matched against a control group of patients receiving just nonoperative treatment, showed a statistically significant improvement in all pain and functioning subcategories. We conclude that a distal tarsal tunnel release with a partial plantar fasciotomy may successfully increase function and decrease pain in patients who fail nonoperative treatment.

Adult↗

Biomechanical testing of cadaveric specimens: importance of bone mineral density assessment.

The bone density of cadaveric specimens is highly variable and has a significant effect on the results of biomechanical testing but it is not often assessed before testing is performed in the lab. Bone mineral density (BMD) tests such as dual X-ray absorptiometry (DXA) are widely available, easy to perform and correlate highly and significantly with bone strength in many modes of failure. We present the results of two different studies performed on cadaveric foot and ankle specimens. In these studies the results vary significantly according to BMD, and this effect is not always eliminated with the use of matched pairs of cadaveric specimens.

Ankle Joint↗

What is the role of serial bone mineral density measurements in patient management?

The ability of dual X-ray absorptiometry (DXA) to monitor bone mineral density (BMD) has been well documented in epidemiologic and pharmaceutical trials. However, its application to monitoring of patients in clinical practice has been subject to recent controversies. Despite these controversies, most clinical centers rely on DXA for monitoring of patients, and therefore guidance is needed. In this article, we report the positions developed by an expert panel of the International Society for Clinical Densitometry on the use of densitometry for the serial measurement of bone mass for monitoring change in BMD. The panel found DXA to be a precise method of measuring change in BMD if used with an appropriate level of least significant change (LSC), at anatomic sites with good precision and response to therapy, and at 1- to 2-yr time intervals. Monitoring is acceptable for determining when therapy is indicated, and if an agent is not therapeutically effective (i.e., when bone loss occurs despite treatment). Each densitometry center should perform an in vivo precision study on individuals similar to the patient population at the center and determine LSC at a 95% confidence level. If such a precision study cannot be performed, benchmark precision might be used, although there was no agreement on what values should be used. The PA spine is the preferred anatomic site for monitoring. The total hip can be used when the spine study is technically invalid. We conclude with recommendations for further research.

Absorptiometry, Photon↗

A prospective trial of night splinting in the treatment of recalcitrant plantar fasciitis: the Ankle Dorsiflexion Dynasplint.

Twelve patients were treated with the Ankle Dorsiflexion Dynasplint (Dynasplint Systems Inc, Severna, Md) for recalcitrant plantar fasciittis. Using a modified plantar fasciitis functional assessment scale and a visual analog pain assessment scale for evaluation, 75% of patients reported improvement ofsymptoms at 1-month follow-up. The average percentage of weekly sleeping hours spent in the splint was 95%. There was no tendency to deterioration of results by 6 months postsplinting. The Ankle Dorsiflexion Dynasplint is effective in the treatment of recalcitrant heel pain in a majority of patients. This study supports its use for the treatment of recalcitrant plantar fasciitis.

Adult↗

The SF-36 general health status survey documents the burden of osteoarthritis and the benefits of total joint arthroplasty: but why should we use it?

OBJECTIVES: To document the disease burden of osteoarthritis and the benefits of total joint replacement by using the Short Form Health Survey (SF-36) general health status survey and evaluate other factors that could affect scores. STUDY DESIGN: Prospective study. PATIENTS AND METHODS: All patients scheduled for primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) (n = 622 preoperatively) in 2 years were surveyed using the SF-36, which assesses health-related quality of life (HRQOL) in patients' physical and social functioning and mental health. Follow-up surveys were administered 12 months after surgery to all patients and 3 and 24 months after surgery to a subset of patients. RESULTS: Preoperatively, patient scores were significantly lower than normative scores in the physical functioning, bodily pain, and social functioning domains. Preoperative scores were not different between THA and TKA patients. Women scored lower than men. Comorbid conditions were weakly associated with low SF-36 scores. Postoperatively, the largest incremental improvement in scores was seen at 3-month follow-up. Scores improved sooner and more substantially in THA vs TKA patients and in men vs women, paralleling improvement in clinical and subjective ratings of postoperative physical function and pain. CONCLUSIONS: The SF-36 has the sensitivity to document improvement in HRQOL after surgery and to reveal differences in THA vs TKA and in men vs women. However, routine use of outcome assessment instruments to monitor this patient population is costly and unjustified in our current healthcare environment.

Aged↗

Use of the SF36 general health status survey to document health-related quality of life in patients with coronary artery disease: effect of disease and response to coronary artery bypass graft surgery.

OBJECTIVE: The purpose of this study was to determine if the SF36 general health status survey has the sensitivity to detect physical function impairments before surgery and the expected improvement in health-related quality of life variables after elective coronary artery bypass graft (CABG) surgery. DESIGN: A prospective, nonrandomized study design was used. OUTCOME MEASURES: The SF36 general health status survey comprises 36 multiple choice questions sorted into 8 categories, or subscales, that describe overall health status. The scores of this survey were used to measure the outcome. INTERVENTION: The SF36 was administered before surgery and at 12-month follow-up. Patients were also queried about the occurrence of angina with normal activities of daily living. RESULTS: Before surgery (n = 81), scores for all SF36 subscales (with the exception of mental health) were lower than published normative data, indicating the disease burden of coronary artery disease. At 12-month follow-up, scores in 6 of 8 subscales improved significantly; general health and role-emotional scores did not change. These changes in SF36 scores at follow-up paralleled a decreased occurrence of angina; before CABG surgery, 75% of patients (61 of 81) had angina; at 12-month follow-up, only 3.7% of patients (3 of 81) had angina. CONCLUSIONS: The SF36 can be used effectively to document changes in health-related quality of life variables in patients with coronary artery disease after CABG surgery.

Activities of Daily Living↗