Rib-to-spine and rib-to-pelvis magnetically controlled growing rods: does the law of diminishing returns still apply?

PURPOSE

The Law Of Diminishing Returns (LODR) has been demonstrated for traditional growing rods, but there is conflicting data regarding the lengthening behavior of Magnetically Controlled Growing Rods (MCGR). This study examines a cohort of patients with early-onset scoliosis (EOS) with rib-to-spine or rib-to-pelvis-based MCGR implants to determine if they demonstrate the LODR, and if there are differences in lengthening behaviors between the groups.

METHODS

A prospectively collected multicenter EOS registry was queried for patients with MCGR with a minimum 2-year follow-up. Patients with rib-based proximal anchors and either spine- or pelvis-based distal anchors were included. Patients with non-MCGR, unilateral constructs, < 3 lengthenings, or missing > 25% datapoints were excluded. Patients were further divided into Primary-MCGR (pMCGR) and Secondary-MCGR (sMCGR).

RESULTS

43 rib-to-spine and 31 rib-to-pelvis MCGR patients were included. There was no difference in pre-implantation, post-implantation and pre-definitive procedure T1-T12 height, T1-S1 height, and major Cobb angles between the groups (p > 0.05). Sub-analysis was performed on 41 pMCGR and 19 sMCGR rib-to-spine patients, and 31 pMCGR and 17 sMCGR rib-to-pelvis patients. There is a decrease in rod lengthenings achieved at subsequent lengthenings for each group: rib-to-spine pMCGR (rho = 0.979, p < 0.001), rib-to-spine sMCGR (rho = 0.855, p = 0.002), rib-to-pelvis pMCGR (rho = 0.568, p = 0.027), and rib-to-pelvis sMCGR (rho = 0.817, p = 0.007). Rib-to-spine pMCGR had diminished lengthening over time for idiopathic, neuromuscular, and syndromic patients (p < 0.05), with no differences between the groups (p > 0.05). Rib-to-pelvis pMCGR neuromuscular patients had decreased lengthening over time (p = 0.01), but syndromic patients had preserved lengthening over time (p = 0.65).

CONCLUSION

Rib-to-spine and rib-to-pelvis pMCGR and sMCGR demonstrate diminished ability to lengthen over subsequent lengthenings.

Palliative care for persons with late-stage Alzheimer's and related dementias and their caregivers: protocol for a randomized clinical trial

BACKGROUND

Limited access to specialized palliative care exposes persons with late-stage Alzheimer's disease and related dementias (ADRD) to burdensome treatment and unnecessary hospitalization and their caregivers to avoidable strain and financial burden. Addressing this unmet need, the purpose of this study was to conduct a randomized clinical trial (RCT) of the ADRD-Palliative Care (ADRD-PC) program.

METHODS

The study will use a multisite, RCT design and will be set in five geographically diverse US hospitals. Lead investigators and outcome assessors will be masked. The study will use 1:1 randomization of patient-caregiver dyads, and sites will enroll N = 424 dyads of hospitalized patients with late-stage ADRD with their family caregivers. Intervention dyads will receive the ADRD-PC program of (1) dementia-specific palliative care, (2) standardized caregiver education, and (3) transitional care. Control dyads will receive publicly available educational material on dementia caregiving. Outcomes will be measured at 30 days (interim) and 60 days post-discharge. The primary outcome will be 60-day hospital transfers, defined as visits to an emergency department or hospitalization ascertained from health record reviews and caregiver interviews (aim 1). Secondary patient-centered outcomes, ascertained from 30- and 60-day health record reviews and caregiver telephone interviews, will be symptom treatment, symptom control, use of community palliative care or hospice, and new nursing home transitions (aim 2). Secondary caregiver-centered outcomes will be communication about prognosis and goals of care, shared decision-making about hospitalization and other treatments, and caregiver distress (aim 3). Analyses will use intention-to-treat, and pre-specified exploratory analyses will examine the effects of sex as a biologic variable and the GDS stage.

DISCUSSION

The study results will determine the efficacy of an intervention that addresses the extraordinary public health impact of late-stage ADRD and suffering due to symptom distress, burdensome treatments, and caregiver strain. While many caregivers prioritize comfort in late-stage ADRD, shared decision-making is rare. Hospitalization creates an opportunity for dementia-specific palliative care, and the study findings will inform care redesign to advance comprehensive dementia-specific palliative care plus transitional care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04948866. Registered on July 2, 2021.

Case report: vertebral body tethering for idiopathic scoliosis in a patient with bilateral phocomelia

PURPOSE

The purpose of this study is to present a case report of a patient with bilateral upper extremity phocomelia with progressive scoliosis, who underwent vertebral body tethering (VBT).

METHODS

This is a case report on the use of VBT in a patient with scoliosis and bilateral congenital phocomelia, with 5 year follow-up.

RESULTS

A male patient with bilateral phocomelia had early onset scoliosis that progressed to 45° at age 10. Surgical options were discussed, including traditional VBT, posterior spinal fusion, growing rods, magnetically controlled growing rods, and vertical expandible prosthetic titanium ribs. These options would limit the flexibility of the spine. Given these pitfalls, VBT was chosen, as it would address the scoliosis while maintaining trunk flexibility. Preoperatively, he had 45° right main thoracic curve, bending to 22°; he was Risser 0 with open triradiate cartilage. He underwent T6-T11 thoracoscopic VBT, with postoperative correction to 37°. Postoperatively, the patient was able to continue to use his lower extremities for writing, feeding, and personal grooming. He had no postoperative complications. At 3 years, his curve was 21°, and at 5 years was 19°.

CONCLUSION

This case describes a novel technique for treating scoliosis in patients with bilateral phocomelia. Other forms of scoliosis surgical treatment limit motion of the spine. Due to this, we present VBT as an option for this unique set of patients for correcting scoliosis, while also preserving trunk flexibility for its role in feeding and self-care.

Lengthening Behavior of Magnetically Controlled Growing Rods in Early-Onset Scoliosis: A Multicenter Study

BACKGROUND

The "law of diminishing returns" is described for traditional growing rods. Magnetically controlled growing rods (MCGRs) have become a preferred implant for the surgical treatment of early-onset scoliosis (EOS). We examined a large cohort of patients with EOS to determine whether the law of diminishing returns applies to MCGRs.

METHODS

A prospectively collected, multicenter registry was queried for patients with EOS treated with MCGRs. Patients with only spine-based implants and a minimum of 2 years of follow-up were included; patients with congenital scoliosis, single rods, <3 lengthenings, or >25% missing data were excluded. Patients were analyzed in 3 cohorts: primary MCGR (pMCGR) had first-time MCGR implants, secondary MCGR (sMCGR) were converted from an MCGR to a new MCGR, and conversion MCGR (cMCGR) were converted from a non-MCGR implant to MCGR.

RESULTS

A total of 189 patients in the pMCGR group, 44 in the cMCGR group, and 41 in the sMCGR group were analyzed. From post-MCGR placement to the most recent follow-up or pre-definitive procedure, there were no differences in the changes in major Cobb angle, T1-S1 height, or T1-T12 height over time between the pMCGR and cMCGR groups. There was a decrease in length achieved at subsequent lengthenings in all cohorts (p < 0.01), and the sMCGR group had a significantly poorer ability to lengthen at each subsequent lengthening versus the pMCGR and cMCGR groups (p < 0.02). The 1-year survival rate was 90.5% for pMCGR, 84.1% for sMCGR, and 76.4% for cMCGR; 2-year survival was 61.5%, 54.4%, and 41.4%, respectively; and 3-year survival was 37.6%, 36.7%, and 26.9%, respectively. Excluding MCGRs still expanding, 27.6% of pMCGRs, 8.8% of sMCGRs, and 17.1% of cMCGRs reached the maximum excursion. Overall, 21.7% reached the maximum excursion. Within the pMCGR cohort, idiopathic and neuromuscular etiologies had a decline in lengthening achieved over time (p < 0.001), while syndromic EOS demonstrated a preserved ability to lengthen over time (p = 0.51). When the etiological groups were compared with each other, the neuromuscular group had the least ability to lengthen over time (p = 0.001 versus syndromic, p = 0.02 versus idiopathic).

CONCLUSIONS

The MCGR experiences the law of diminishing returns in patients with EOS. We found that only 21.7% of rods expanded to within 80% of the maximum excursion.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Time to Completion of Pediatric PROMIS Computerized Adaptive Testing Measures and the SRS-22r in an Adolescent Idiopathic Scoliosis Population

BACKGROUND

Patient-reported outcome measures are useful tools to quantify patients' pre-treatment and post-treatment symptoms. Historically used "legacy measures", such as the Scoliosis Research Society-22 revised questionnaire (SRS-22r), are often disease-specific and can be time-intensive. Recently developed Patient-Reported Outcomes Measurement Information System (PROMIS) computerized adaptive testing (CAT) measures may reduce administrative burdens and permit more efficient outcome collection within clinic workflows. In an era of medicine where payments are becoming tied to outcomes, we sought to assess the time to completion (TTC) of 8 pediatric PROMIS CAT measures and the SRS-22r in adolescents with idiopathic scoliosis.

MATERIALS AND METHODS

Patients presenting to a large, urban tertiary referral hospital were prospectively enrolled into the study. Subjects were first-time survey respondents in various phases and types of treatment for adolescent idiopathic scoliosis. In total, 200 patients ranging from 10 to 17 years old completed 8 Pediatric PROMIS CATs and the SRS-22r. PROMIS CATs administered include Physical Activity, Mobility, Anxiety, Depressive symptoms, Peer Relationships, Physical Stress Experiences, Pain Behavior and Pain Interference. TTC was calculated using start and stop timestamps in the REDCap software.

RESULTS

The mean (±SD) TTC for each PROMIS CAT was 1.1 (±0.9) minutes with physical activity, mobility, anxiety, depressive symptoms, peer relationships, physical stress experiences, pain behavior, and pain interference taking 1.2, 1.4, 1.0, 0.9, 1.2, 1.0, 1.0, and 1.2 minutes on average to complete, respectively. Mean TTC for the SRS-22r was 5.2 (±3.0) minutes.

CONCLUSIONS

In this pediatric orthopaedic cohort, completion of 8 PROMIS CATs demonstrated minimal test-taker burden and time required for completion. These findings support rapid and easily integrable PROMIS CATs in clinical practice to aid in increased delivery of efficient, patient-centered care.

LEVEL OF EVIDENCE

III, cross-sectional study.

Construct Validity of Pediatric PROMIS Computerized Adaptive Testing Measures in Children With Adolescent Idiopathic Scoliosis

BACKGROUND

The use of patient-reported outcome measures, especially Patient-Reported Outcomes Measurement Information System (PROMIS) measures, has increased in recent years. Given this growth, it is imperative to ensure that the measures being used are validated for the intended population(s)/disease(s). Our objective was to assess the construct validity of 8 PROMIS computer adaptive testing (CAT) measures among children with adolescent idiopathic scoliosis (AIS).

METHODS

We prospectively enrolled 200 children (aged 10 to 17 y) with AIS, who completed 8 PROMIS CATs (Anxiety, Depressive Symptoms, Mobility, Pain Behavior, Pain Interference, Peer Relationships, Physical Activity, Physical Stress Experiences) and the Scoliosis Research Society-22r questionnaire (SRS-22r) electronically. Treatment categories were observation, bracing, indicated for surgery, or postoperative from posterior spinal fusion. Construct validity was evaluated using known group analysis and convergent and discriminant validity analyses. Analysis of variance was used to identify differences in PROMIS T -scores by treatment category (known groups). The Spearman rank correlation coefficient ( rs ) was calculated between corresponding PROMIS and SRS-22r domains (convergent) and between unrelated PROMIS domains (discriminant). Floor/ceiling effects were calculated.

RESULTS

Among treatment categories, significant differences were found in PROMIS Mobility, Pain Behavior, Pain Interference, and Physical Stress Experiences and in all SRS-22r domains ( P <0.05) except Mental Health ( P =0.15). SRS-22r Pain was strongly correlated with PROMIS Pain Interference ( rs =-0.72) and Pain Behavior ( rs =-0.71) and moderately correlated with Physical Stress Experiences ( rs =-0.57). SRS-22r Mental Health was strongly correlated with PROMIS Depressive Symptoms ( rs =-0.72) and moderately correlated with Anxiety ( rs =-0.62). SRS-22r Function was moderately correlated with PROMIS Mobility ( rs =0.64) and weakly correlated with Physical Activity ( rs =0.34). SRS-22r Self-Image was weakly correlated with PROMIS Peer Relationships ( rs =0.33). All unrelated PROMIS CATs were weakly correlated (| rs |<0.40). PROMIS Anxiety, Mobility, Pain Behavior, and Pain Interference and SRS-22r Function, Pain, and Satisfaction displayed ceiling effects.

CONCLUSIONS

Evidence supports the construct validity of 6 PROMIS CATs in evaluating AIS patients. Ceiling effects should be considered when using specific PROMIS CATs.

LEVEL OF EVIDENCE

Level II, prognostic.

Morphometric analysis of the proximal thoracic pedicles in Lenke II and IV adolescent idiopathic scoliosis: an evaluation of the feasibility for pedicle screw insertion

PURPOSE

Pedicles on the concave side of the proximal thoracic (PT) curve in adolescent idiopathic scoliosis (AIS) patients with Lenke II and IV deformities tend to be narrow and dysplastic, making pedicle screw (PS) insertion challenging. The aim of this study was to evaluate the feasibility for PS placement in these patients using pedicle chord length, diameter, and channel morphology.

METHODS

In this retrospective study, 56 consecutive AIS patients with Lenke II or IV curves who underwent instrumented posterior spinal fusion (PSF) were studied. The mean age at surgery was 14.8 years and the mean PT curve measured 45°. Two independent investigators evaluated all visible pedicles from T₁ to T₆ vertebral levels using axial images from intraoperative computed tomography-guided navigation recording the pedicle: (1) maximum transverse diameter 'd' at the isthmus, (2) maximum chord length 'l', and (3) qualitative assessment of the channel morphology (types A-D).

RESULTS

Two hundred and sixty-eight concave and 264 convex pedicles were measured. The mean 'd' of the concave pedicles at T₃ and T₄ was < 3.0 mm, compared to > 5.0 mm for the convex counterparts (p < 0.001). Of all concave pedicle channels, 48% had morphology characteristics that were riskier for PS cannulation (type C or D) compared to 2% of all convex pedicle channels (type A or B) (p < 0.001).

CONCLUSION

Almost half of all concave pedicles have morphologic characteristics that make them too small to accommodate a PS. Though PSs could be inserted using an in-out-in technique in these patients, alternative fixation anchors may improve strength and safety.

Entire-spine Magnetic Resonance Imaging Findings and Costs in Children With Presumed Adolescent Idiopathic Scoliosis

BACKGROUND

Patients with adolescent idiopathic scoliosis (AIS) are commonly monitored for curve progression with spinal radiographs; however, the utility of magnetic resonance imaging (MRI) screening is unclear. The purpose of this study was to assess the findings of screening MRI for patients with a nonsurgical curve size ordered during routine clinical care and compare them with MRI ordered for patients with large curves as part of preoperative screening.

METHODS

All consecutive patients with presumed AIS who underwent entire-spine MRI with a presumed diagnosis of idiopathic scoliosis at a single institution between 2017 and 2019 were retrospectively reviewed. Patients were stratified based on MRI indication into the following groups: preoperative evaluation, pain, neurological symptoms, abnormal radiographic curve appearance, rapidly progressive curve, and other. Neural axis abnormalities recorded included concern for tethered spinal cord, syringomyelia, and Chiari malformation. The MRI findings of preoperative patients with large curves were compared with all other patients. The number needed to diagnose (NND) a neurological finding was calculated in patients whose MRIs were ordered during routine clinical care. The amount charged for each patient undergoing entire-spine MRI was determined by review of our institution's Financial Decision Support system.

RESULTS

There were 344 patients included in this study with 214 (62%) MRIs performed for preoperative evaluation. Although MRI abnormalities were found in 49% of patients, only 7.0% (24/344) demonstrated neural axis abnormalities with no difference between preoperative and other indications (P=0.37). For patients with nonsurgical curves undergoing MRI due to a complaint of back pain (n=28), there were no neural axis abnormalities, and a lower rate of disk herniation/degenerative changes detected compared with preoperative MRI (3.6% vs. 18%, P=0.06). Among the 15 patients undergoing MRI for a neurological concern, 1 had a neural axis abnormality that required surgical detethering. The NND for MRI to detect a neural axis abnormality that potentially required neurosurgical intervention in nonpreoperative patients with a neurological concern was 34.4. The average cost for MRI was $17,816 (range: $2601 to $22,411) with a total cost of $2,368,439 for nonsurgical curves.

CONCLUSIONS

Entire-spine MRI for nonpreoperative indications including pain, abnormal radiographic curve appearance, and rapid curve progression has minimal utility for patients with AIS. For patients with neurological complaints, the NND a potentially treatment-altering finding with MRI is 34.4.

LEVEL OF EVIDENCE

Level II-diagnostic.

Difficulties in Treating Postirradiation Kyphosis in Adults: A Series of Five Cases

STUDY DESIGN

Clinical case series.

OBJECTIVE

To assess objective outcomes of surgical correction of post-external beam radiation therapy (ERBT) kyphosis in a series of five adults.

SUMMARY OF BACKGROUND DATA

EBRT is a well-established treatment for many cancers in children and adults. One complication associated with EBRT is postirradiation spine deformity. Scoliosis is the most common deformity, but kyphosis also occurs frequently. Differences in deformity patterns are likely related to the location and intensity of radiation. To our knowledge, no studies have addressed treatment of these deformities in adults, and the most recent case series (of children) was published in 2005.

METHODS

We present a series of five adults who underwent surgery for postirradiation kyphosis, with a mean follow-up of 3.8 years (range, 2.5-6.2 years).

RESULTS

Surgery improved the kyphotic deformity in all patients. Overall mean kyphotic deformity correction was 56° and was larger for cervical/cervicothoracic deformities (mean, 76°) than for lumbar deformities (mean, 42°) at midterm follow-up. Patients reported significant improvements in pain and self-image. Consistent with prior case series of children, we observed a high rate of complications (mean, 1.4 complications per patient) in adults. Three patients each underwent an unplanned surgical procedure because of a complication.

CONCLUSION

The surgical treatment of postirradiation kyphotic spinal deformity is challenging, with common postoperative complications such as infection, instrumentation failure, and pseudarthrosis. However, with modern surgical techniques and spinal instrumentation, excellent deformity correction can be achieved and maintained. We recommend performing a two-stage procedure for cervicothoracic deformity, with anterior release followed by posterior fusion and instrumentation. In thoracolumbar deformities, correction can be achieved through single-stage posterior fusion. Rigid spinopelvic fixation with sacral-alar-iliac screws and second-stage anterior lumbar interbody fusion at L5-S1 is recommended to reduce nonunion risk. Cement augmentation of proximal and distal anchors can help prevent junctional failure.

LEVEL OF EVIDENCE

Level IV.

The Military Extremity Trauma Amputation/Limb Salvage (METALS) Study: Outcomes of Amputation Compared with Limb Salvage Following Major Upper-Extremity Trauma

BACKGROUND

Severe upper-extremity injuries account for almost one-half of all extremity trauma in recent conflicts in the Global War on Terror. Few long-term outcomes studies address severe combat-related upper-extremity injuries. This study's objective was to describe long-term functional outcomes of amputation compared with those of limb salvage in Global War on Terror veterans who sustained severe upper-extremity injuries. Limb salvage was hypothesized to result in better arm and hand function scores, overall functional status, and quality of life, with similar pain interference.

METHODS

This retrospective cohort study utilized data from the Military Extremity Trauma Amputation/Limb Salvage (METALS) study for a subset of 155 individuals who sustained major upper-extremity injuries treated with amputation or limb salvage. Participants were interviewed by telephone 40 months after injury, assessing social support, personal habits, and patient-reported outcome instruments for function, activity, depression, pain, and posttraumatic stress. Outcomes were evaluated for participants with severe upper-extremity injuries and were compared with participants with concomitant severe, lower-extremity injury. The analysis of outcomes comparing limb salvage with amputation was restricted to the 137 participants with a unilateral upper-extremity injury because of the small number of patients with bilateral upper-extremity injuries (n = 18).

RESULTS

Overall, participants with upper-extremity injuries reported moderate to high levels of physical and psychosocial disability. Short Musculoskeletal Function Assessment (SMFA) scores were high across domains; 19.4% screened positive for posttraumatic stress disorder (PTSD), and 12.3% were positive for depression. Nonetheless, 63.6% of participants were working, were on active duty, or were attending school, and 38.7% of participants were involved in vigorous recreational activities. No significant differences in outcomes were observed between patients who underwent limb salvage and those who underwent amputation.

CONCLUSIONS

Severe, combat-related upper-extremity injuries result in diminished self-reported function and psychosocial health. Our results suggest that long-term outcomes are equivalent for those treated with amputation or limb salvage. Addressing or preventing PTSD, depression, chronic pain, and associated health habits may result in less disability burden in this population.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Pediatric Gartland Type-IV Supracondylar Humeral Fractures Have Substantial Overlap with Flexion-Type Fractures

BACKGROUND

Knowledge is limited about the diagnosis and treatment of modified Gartland type-IV supracondylar humeral fractures. We determined the prevalence of type-IV fractures, identified preoperative characteristics associated with these injuries, and assessed operative treatment characteristics.

METHODS

We retrospectively identified patients <16 years of age who underwent operative treatment of a supracondylar humeral fracture at 2 centers between 2008 and 2016. We compared patient, injury, and treatment characteristics between type-IV and type-III fracture groups (1:4, cases:controls). Preoperative radiographs were assessed by 4 pediatric orthopaedists blinded to fracture type. The odds of a fracture being type IV were assessed using univariate logistic regression for individual radiographic parameters. Significance was set at alpha = 0.05.

RESULTS

Type-IV fractures accounted for 39 (1.3%) of the supracondylar humeral fractures treated operatively during the study period. A type-IV fracture was associated with the following radiographic parameters: flexion angulation (odds ratio [OR] = 17; 95% confidence interval [CI] = 4.9 to 59), valgus angulation (OR = 5.6; 95% CI = 1.6 to 20), and lateral translation (OR = 4.1; 95% CI = 1.6 to 11) of the distal fragment; osseous apposition between the proximal and distal fragments (OR = 4.0; 95% CI = 1.8 to 9.0); and propagation of the fracture line toward the diaphysis of the proximal segment (OR = 9.2; 95% CI = 1.6 to 53). We found no significant differences in patient or injury characteristics between the groups. Compared with type-III fractures, type-IV fractures were treated more frequently with open reduction and percutaneous pinning (13% compared with 3.8%; p = 0.04) and were associated with longer mean operative time (82 ± 42 compared with 63 ± 28 minutes; p = 0.001).

CONCLUSIONS

We identified 5 preoperative radiographic parameters associated with greater odds of a supracondylar humeral fracture being type IV rather than type III. No patient or injury characteristic differed significantly between the groups. Substantial overlap likely exists between type-IV and flexion-type fractures. Type-IV fractures were associated with longer operative time and were treated with open reduction more frequently than were type-III fractures.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Catastrophic Failure of a Carbon-Fiber-Reinforced Polyetheretherketone Tibial Intramedullary Nail: A Case Report

CASE

We present a case of a rare low-energy catastrophic failure of a carbon-fiber-reinforced polyetheretherketone tibial intramedullary nail at 10 weeks after placement in a 36-year-old man. We describe our experience with extraction of the device.

CONCLUSION

Carbon-fiber composite implants are approved for clinical use in orthopaedic trauma applications. The rare failure of carbon-fiber implants presents unique challenges because typical extraction techniques cannot be used. With the patient described herein, a terminally threaded guidewire was used to cannulate and extract the distal segment of the nail.

Performance of microbial identification by MALDI-TOF MS and susceptibility testing by VITEK 2 from positive blood cultures after minimal incubation on solid media

Bloodstream infections (BSIs) are a leading cause of patient morbidity and mortality. Rapid identification of organisms from BSIs is critical for initiating targeted antimicrobial therapy. Although many methods exist for rapid identification, they do not provide detailed or definitive susceptibility information. We assessed the utility of both the VITEK MS and Bruker Biotyper MALDI-TOF mass spectrometers to identify organisms from a positive blood culture bottle after only 4 h of growth on solid media compared to identification from overnight growth using the VITEK MS. Additionally, we determined whether this limited growth could yield accurate antimicrobial susceptibility testing (AST) results compared to overnight growth using the VITEK 2 AST system. Overall, identifications using the VITEK MS and Biotyper had agreements of 127/150 (84%) and 133/150 (88%), respectively. For rapid AST, the overall categorical agreement was 1010/1017 (99.3%), where Gram-negative bacteria had concordant results for 743/750 (99.1%) organism-drug combinations and Gram-positive bacteria had concordant results for 265/267 (99.3%). Gram-negative bacteria had 4, 2, and 1 minor, major, and very major discrepancies, respectively, while Gram-positive bacteria had no minor errors, one major, and one very major discrepancy. In conclusion, organisms grown for only 4 h on solid media were accurately identified by MALDI-TOF MS and have concordant phenotypic AST profiles. This method can also be implemented using common commercial instruments, providing a way to improve upon identification and gain detailed susceptibility information without significant additional laboratory costs.

Selenoprotein P and apolipoprotein E receptor-2 interact at the blood-brain barrier and also within the brain to maintain an essential selenium pool that protects against neurodegeneration

Selenoprotein P (Sepp1) and its receptor, apolipoprotein E receptor 2 (apoER2), account for brain retaining selenium better than other tissues. The primary sources of Sepp1 in plasma and brain are hepatocytes and astrocytes, respectively. ApoER2 is expressed in varying amounts by tissues; within the brain it is expressed primarily by neurons. Knockout of Sepp1 or apoER2 lowers brain selenium from ∼120 to ∼50 ng/g and leads to severe neurodegeneration and death in mild selenium deficiency. Interactions of Sepp1 and apoER2 that protect against this injury have not been characterized. We studied Sepp1, apoER2, and brain selenium in knockout mice. Immunocytochemistry showed that apoER2 mediates Sepp1 uptake at the blood-brain barrier. When Sepp1(-/-) or apoER2(-/-) mice developed severe neurodegeneration caused by mild selenium deficiency, brain selenium was ∼35 ng/g. In extreme selenium deficiency, however, brain selenium of ∼12 ng/g was tolerated when both Sepp1 and apoER2 were intact in the brain. These findings indicate that tandem Sepp1-apoER2 interactions supply selenium for maintenance of brain neurons. One interaction is at the blood-brain barrier, and the other is within the brain. We postulate that Sepp1 inside the blood-brain barrier is taken up by neurons via apoER2, concentrating brain selenium in them.

Medical student appraisal: electronic resources for inpatient pre-rounding

BACKGROUND

Pre-rounding is essential to preparing for morning rounds. Despite its importance, pre-rounding is rarely formally taught within the medical school curriculum and more often informally learned by modeling residents. The evolution of mobile applications provides opportunities to optimize this process.

OBJECTIVES

To evaluate three options available to medical students while pre-rounding and promote adoption of mobile resources in clinical care.

METHODS

Six medical students formed the evaluation cohort. Students were surveyed to assess pre-rounding practices. Participants utilized paper-based pre-rounding templates for two weeks followed by two weeks of the electronic note-taking service Evernote. A review of mobile applications on the iTunes and Google Play stores was performed, with each application informally reviewed by a single student. The application Scutsheet was selected for formal review by all students. Data was collected from narrative responses supplied by students throughout the evaluation periods and aggregated to assess strengths and limitations of each application.

RESULTS

Pre-study responses demonstrated two consistent processes: verbal sign-out of overnight events and template use to organize patient information. The paper-based template was praised for its organization and familiarity amongst residents, but perceived as limited by the requirement of re-copying data into the hospital's electronic medical record (EMR). Evernote excelled due to compatibility across multiple operating systems, including accessibility from clinical workstations and ability to copy notes into the hospital's EMR. Scutsheet allowed for retention of data across multiple hospital days, but was limited by inability to export data or modify the electronic template. Aggregated user feedback identified the abilities to customize templates and copy information into the EMR as two prevailing characteristics that enhanced the efficiency of pre-rounding.

DISCUSSION

Mobile devices offer the potential to enhance pre-rounding efficiency for medical students and residents. A customizable Evernote-based system is described in sufficient detail for reproduction by interested students.

Medical student appraisal: applications for bedside patient education

BACKGROUND

Medical students are often afforded the privilege of counselling patients. In the past resources were limited to pen and paper or anatomic models. The evolution of mobile applications allows for limitless access to resources that facilitate bedside patient education.

OBJECTIVES

To evaluate the utility of six applications in patient education and promote awareness of implementing mobile resources in clinical care.

METHODS

Six medical students rotating on various clerkships evaluated a total of six mobile applications. Strengths, limitations, and suggested uses in clinical care were identified. Applications included Meditoons™, VisiblePatient™, DrawMD™, CardioTeach™, Visual Anatomy™, and 360° Patient Education Suite™. Data was generated from narrative responses supplied by each student during their evaluation period.

RESULTS

Bedside teaching was enhanced by professional illustrations and animations depicting anatomy and pathophysiology. Impromptu teaching was facilitated, as resources were conveniently available on a student's smartphone or tablet. The ability to annotate and modify images and subsequently email to patients was an extraordinary improvement in provider-patient communication. Universal limitations included small smartphone screens and the novelty of new technology.

DISCUSSION

Mobile applications have the potential to greatly enhance patient education and simultaneously build rapport. Endless opportunities exist for their integration in clinical practice, particularly for new diagnoses, consent for procedures, and at time of discharge. Providers should be encouraged to try new applications and utilize them with patients.

Defining parkinsonism in the Canadian Study of Health and Aging

This study sought an operational definition of parkinsonism in elderly people (n = 2,914) who underwent a clinical examination in the Canadian Study of Health and Aging (CSHA). Parkinsonism was defined as having two of the following features: (1) bradykinesia of face or limbs, (2) resting tremor, (3) rigidity, and (4) abnormality of gait and posture. The association of parkinsonism with other parkinsonian-related features (prior diagnosis of Parkinson's disease, use of drugs with extrapyramidal side effects, and use of antiparkinsonian medications) and variables not expected to be related to parkinsonism (stroke and Hachinski score > 5) was determined. Parkinsonism was identified in 337 people (11.6%). It was significantly more likely with other parkinsonian-related characteristics, and was not associated with a history of stroke, but was slightly higher among those subjects with a Hachinski score > 5. Posture and gait abnormalities were significantly associated with other parkinsonian-related variables, but were also more common among subjects with stroke-related features. When the gait and posture disturbance category was excluded as a parkinsonian sign, the narrower definition was more specific but less sensitive in detecting cases with a clinical diagnosis of Parkinson's disease. Despite limitations, the approach presented in this article is a valid method to operationalize parkinsonism from the dataset.

Racial and state differences in the designation of advance directives in nursing home residents

OBJECTIVES

To examine racial and state differences in the use of advance directives and surrogate decision-making in a nursing home population.

DESIGN

A retrospective cohort study.

SETTING

Nursing homes in the states of California (CA), Massachusetts (MA), New York (NY), and Ohio (OH).

PARTICIPANTS

Nursing home residents: 130,308 in CA, 59,691 in MA, 112,080 in NY, and 98,954 in OH.

MEASUREMENTS

Minimum Data Set information concerning resident race and whether or not residents have a living will (LW), a do not resuscitate (DNR) order, or a surrogate decision-maker (SDM).

RESULTS

The proportion of LWs, DNR orders, and SDMs varied significantly (P < .0001) by racial categories in each state. In general, whites were distinctly different from other racial categories. Whites were significantly more likely to have a LW (odds ratio (OR) = 1.9 (CA), OR = 2.2 (NY), OR = 4.9 (OH)), a DNR order (OR = 2.4 (CA), OR = 2.4 (MA), OR = 3.3 (NY), OR = 3.2 (OH)), and a SDM (OR = 1.1 (CA), OR = 1.2 (NY), OR = 1.6 (OH)) than were nonwhites, after adjusting for potentially confounding factors. Significant state differences (P < .0001) were observed in LWs, DNR orders, and SDMs and were most pronounced in residents of Ohio, who were significantly more likely to have a LW than were residents in other states (OR = 9.3).

CONCLUSIONS

Various resident characteristics explain some of the racial differences, although whites are still more likely to have a LW, a DNR order, or an SDM independent of various resident characteristics included in the adjusted analyses. This pattern is observed in all states, although the ORs varied by state. Some of these differences may be due to distinct cultural approaches to end-of-life care and lack of knowledge and understanding of advance directives. The distinctly higher rates of LWs among all racial groups in Ohio than in other states suggest that states can potentially increase the use of advance directives through intervention.

The hierarchy of functional loss associated with cognitive decline in older persons

OBJECTIVES

We studied a representative cohort of community-dwelling elderly persons to (i) examine the relationship between the loss of specific functional activities and cognitive status at the time of these losses, (ii) compare the cognitive status of participants who have and have not lost independence in these functional activities, and (iii) determine whether a hierarchical scale of functional loss is associated with declining cognitive status.

METHODS

A cohort of 5874 community-dwelling persons aged 65 years and older from the Canadian Study of Health and Aging I and II were analyzed. At baseline and 5 years later, cognitive status with the Modified Mini-Mental State Examination (3MS) and functional status with 14 Older American Resources and Services (OARS) items were measured. For each OARS functional item, the mean 3MS scores for persons who lost independence during the 5-year period versus those who did not were compared.

RESULTS

For each functional item, the 5-year decline in 3MS scores of persons who lost independence were significantly greater than those who remained independent (e.g., ability to do finances), with an 18-point decline for those who lost independence and a 2-point decline for those who retained independence. A hierarchy of functional items existed, with instrumental activities of daily living (ADLs) (e.g., shopping, banking, and cooking) being lost at higher cognitive scores than basic ADL items (e.g., eating, dressing, and walking), although there was some overlap.

CONCLUSIONS

This is the first prospective study using a large representative cohort of elderly persons to demonstrate that progressive cognitive decline is associated with a specific pattern of loss of functional tasks. Clear cognitive thresholds at which development of dependency in OARS functional items occurred. By providing estimates of the cognitive status of persons at the time at which they developed dependency in specific functional items, a natural hierarchy of functional loss associated with cognitive decline emerged. For caregivers, clinicians, and health policy makers, this information can help anticipate the pattern of functional decline and the subsequent care needs of persons with declining cognition, potentially improving the quality of life of these persons and their caregivers and playing an important part in health care planning.

Compressive properties of cancellous bone defects in a rabbit model treated with particles of natural bone mineral and synthetic hydroxyapatite

A rabbit model was developed to evaluate the compressive mechanical properties of cancellous bone defects treated with particles of selected bone graft substitute materials. A novel feature of the model was the precise retrieval of the site of implantation. A notable finding was a 9-fold increase in the modulus of elasticity of the defect implanted with a synthetic hydroxyapatite material after 26 weeks when compared to the modulus of the trabecular bone normally at the site. The compressive modulus of lesions treated with particles of a natural bovine bone mineral (anorganic bovine bone) was closer to the normal modulus of the cancellous bone at the site. While the compressive strength of the anorganic bone particles was less than that of normal bone, the site implanted with the bone mineral particles achieved compressive strength greater than normal after 6 weeks. Moreover, the anorganic bone particles accelerated the increase in strength of the lesion, at 6 weeks exceeding the strength achieved by the untreated defect after 26 weeks. The potential problem associated with the disparity in the compressive modulus between sites implanted with the synthetic HA particles and surrounding bone is discussed.

Randomized controlled trial of quadriceps training after proximal femoral fracture

OBJECTIVE

To determine whether systematic progressive high-intensity quadriceps training increases leg extensor power and reduces disability in patients rehabilitating after proximal femoral fracture.

DESIGN

Open parallel group randomized controlled trial comparing the addition of six weeks quadriceps training (40 patients) with standard physiotherapy alone (40 patients). The training group exercised twice weekly, with six sets of 12 repetitions of knee extension (both legs), progressing up to 80% of their one-repetition maximum.

SETTING

Orthogeriatric unit, and community follow-up.

SUBJECTS

Eighty patients rehabilitating after proximal femoral fracture.

MAIN OUTCOME MEASURES

Measurements of leg extensor power (Nottingham Power Rig), functional mobility (elderly mobility score), disability (Barthel Index) and quality of life (Nottingham Health Profile) were made at baseline, after six weeks (at the end of the intervention) and at 16 weeks.

RESULTS

Leg extensor power increased significantly in the quadriceps training group (fractured leg mean improvement at six weeks 157% (standard error 16), nonfractured leg 80% (12)) compared with the control group (63% (11) and 26% (8) respectively, unpaired Student's t-test p = 0.007 and p = 0.01 for between-group comparisons). Significant benefits were maintained at 16 weeks. Quadriceps training resulted in a greater increase in elderly mobility scale score compared with standard rehabilitation (between-group difference of 2.5 (95% CI 1.1,3.8) at week 6 and 1.9 (0.4,3.4) at week 16). Barthel score increased significantly from week 0 to 6 in the quadriceps training group compared with controls (Mann-Whitney U-test p = 0.05). Patients in the quadriceps training group scored significantly better in the energy subscore of the Nottingham Health Profile at the end of follow-up (Mann-Whitney U-test p = 0.0185).

CONCLUSIONS

Progressive high-intensity quadriceps training in elderly proximal femoral fracture patients increased leg extensor power and reduced disability. This was accompanied by an increase in energy as measured by the Nottingham Health Profile. This intervention may provide a simple practical way of improving outcome in these patients.

Movement and sound generation by the toadfish swimbladder

Although sound-producing (sonic) muscles attached to fish swimbladders are the fastest known vertebrate muscles, the functional requirement for such extreme speed has never been addressed. We measured movement of the swimbladder caused by sonic muscle stimulation in the oyster toadfish Opsanus tau and related it to major features of the sound waveform. The movement pattern is complex and produces sound inefficiently because the sides and bottom of the bladder move in opposite in and out directions, and both movement and sound decay rapidly. Sound amplitude is related to speed of swimbladder movement, and slow movements do not produce perceptible sound. Peak sound amplitude overlaps fundamental frequencies of the male's mating call because of muscle mechanics and not the natural frequency of the bladder. These findings suggest that rapid muscle speed evolved to generate sound from an inefficient highly damped system.

A comparison of mobility assessments in a geriatric day hospital

OBJECTIVE

To assess the sensitivity of the Elderly Mobility Scale (EMS) to detect improvements in mobility after physiotherapy in comparison with the Barthel Index (BI) and Functional Ambulation Category (FAC) in routine clinical day hospital practice.

SUBJECTS

Eighty-three patients who completed a course of physiotherapy were studied.

METHODS

Each was assessed by an independent physiotherapist before and after a programme of physiotherapy, using the EMS, BI and FAC.

RESULTS

The mean age was 79 years (SD 7.7). Fifty-three out of 83 (64%) patients were female and 92% were community dwelling. The median number of physiotherapy sessions undergone by each patient was 9 (range 3-51). All three scales detected an improvement in mobility with physiotherapy (p < 0.001). However, using the EMS, 68 out of 82 (83%) patients had a detectable improvement in mobility compared with only 34 out of 80 (42%) using the BI and 28 out of 81 (35%) using the FAC. Using a matched-pairs comparison, the EMS was significantly more likely to detect an improvement in mobility following physiotherapy within the study group than the BI (p < 0.001) or the FAC (p < 0.001).

CONCLUSION

Although all three scales detected improvements in mobility, the EMS detected mobility improvements in a significantly greater number of patients.

The association between antiulcer medication and initiation of cobalamin replacement in older persons

As chronic use of antiulcer medications might predispose older persons to cobalamin deficiency, we studied participants (> 65 years) in the clinical examination of the Canadian Study of Health and Aging to test the association between the use of an antiulcer medication (histamine-2 blocker or proton pump inhibitor) at baseline with initiation of cobalamin replacement during the 5 year follow-up period. Of 1054 eligible subjects, 125 (11.7%) were taking an antiulcer medication at baseline. At follow-up, 49 (4.6%) had started cobalamin replacement. Antiulcer medication use at baseline was significantly associated with the initiation of cobalamin therapy (odds ratio 2.56, 95% confidence interval 1.30-5.05), even after adjusting for age, gender and institutional residence (odds ratio 2.61, 95% confidence interval 1.31-5.23). There is an independent association between the use of antiulcer medication and initiation of cobalamin therapy. While the relationship is not unambiguously causal, this finding underscores the need for judicious prescribing of antiulcer medications for older persons.

Influence of bone densitometry results on the treatment of osteoporosis

BACKGROUND

Measurement of bone mineral density is widely used to diagnose osteoporosis. The objectives of this study are to determine how bone densitometry affects subsequent treatment of osteopenia and osteoporosis with either hormone replacement therapy or bisphosphonates and to examine clinical factors associated with starting either therapy after bone densitometry.

METHODS

We conducted a prospective study involving women over 50 years of age who were referred to a tertiary care hospital for the first time to undergo bone density measurement using dual-energy x-ray absorptiometry (DXA). Baseline clinical data were collected through face-to-face interviews before the test. Subsequently, the scans were reviewed and categorized as showing no bone loss, osteopenia or osteoporosis, based on World Health Organization criteria. Three months after DXA, subjects were contacted by telephone to determine their understanding of the test results and any new treatments started or recommended since the scan.

RESULTS

Of 383 women recruited at the time of their DXA, 335 (87.5%) completed the 3-month follow-up. Among those reached at follow-up, DXA results showed no bone loss in 119 (35.5%), osteopenia in 137 (40.9%) and osteoporosis in 79 (23.6%). The proportion of subjects with osteoporosis receiving either hormone replacement therapy or bisphosphonate therapy was 15.2% before the test, increasing to 63.3% after the scan. The following factors were independently associated with the initiation of either therapy: actual DXA result showing osteoporosis (odds ratio [OR] 7.2; 95% confidence interval [CI] 1.7-30.3), compared with a normal scan; subjects' perception that their scan showed bone loss (osteopenia, or osteoporosis) (OR 13.5; 95% CI 4.0-45.5) or that they were unclear about the results (OR 5.4; 95% CI 1.6-18.8), compared with the perception that the results were normal; and discussion of the DXA results with a physician (OR 5.5; 95% CI 1.9-16.0).

INTERPRETATION

The proportion of women with osteoporosis receiving hormone replacement therapy or bisphosphonate therapy increases after diagnosis with densitometry. However, communication by physicians so that patients understand their test results is a critical component in the initiation of therapy after bone densitometry.

A decision aid for long-term tube feeding in cognitively impaired older persons

OBJECTIVE

To describe the development and evaluation of a decision aid for long-term tube feeding in cognitively impaired older people.

DESIGN

Before-and-after study.

SETTING

Acute care hospitals in Ottawa, Canada.

PARTICIPANTS

Substitute decision makers for 15 cognitively impaired inpatients 65 years and older being considered for placement of a percutaneous endoscopic gastrostomy tube.

MEASUREMENTS

Questionnaires were used to compare the substitute decision makers' knowledge, decisional conflict, and predisposition regarding feeding tube placement before and after exposure to the decision aid. The acceptability of the decision aid was also assessed.

RESULTS

Substitute decision makers significantly increased their knowledge (P = .004) and decreased their decisional conflict (P = .004) regarding long-term tube feeding after using the decision aid. The impact of the decision aid on predisposition toward the intervention was greatest for those who were unsure of their preferences at baseline. All substitute decision makers found the decision aid helpful and acceptable despite very difficult and emotional circumstances.

CONCLUSIONS

A decision aid improves the decision-making process for long-term tube feeding in cognitively impaired older patients by decreasing decisional conflict and by promoting decisions that are informed and consistent with personal values. There are particular challenges for developing and evaluating these tools in the context of end-of-life decisions.

A cross-national comparison of institutionalized tube-fed older persons: the influence of contrasting healthcare systems

OBJECTIVE

Different health care settings may influence the type of patients selected for long-term tube-feeding. Clinical characteristics of older, tube-fed institutionalized subjects living in Ontario, Canada were compared with those in the United States (US).

DESIGN

A cross-sectional cohort study Setting: Nursing homes in the states of Mississippi, Texas, and Vermont (US) and chronic care facilities in Ontario.

PARTICIPANTS

Tube-fed residents older than age 65 living in facilities in the US between January 1, 1996, and March 31, 1997 (n = 859), and in institutions in Ontario between January 1, 1996, and December 31, 1997 (n = 913).

MEASUREMENTS

Data were obtained from Minimum Dataset assessments at both sites. Demographic and clinical characteristics were compared between tube-fed subjects living in the US and those in Canadian facilities.

RESULTS

In a logistic regression model, the following characteristics were significantly more likely to be found among tube-fed subjects in the US than in those in Ontario: greater impairment of cognitive performance, cardiopulmonary disease, a diagnosis of dementia, female, and age greater than 80 years. Characteristics that were significantly less likely to be present among the US tube-fed subjects included: recurrent lung aspirations, a chewing or swallowing problem, do not resuscitate status, restraint use, weight loss, and stroke.

CONCLUSIONS

Clinical characteristics differ between older, institutionalized tube-fed subjects in Ontario and in US nursing homes. In order to put these differences into context, consideration must be given to how the contrasting healthcare systems in these two countries may drive decision-making for long-term tube-feeding.

Survival after percutaneous endoscopic gastrostomy placement in older persons

BACKGROUND

The prolongation of life is an important consideration in the decision to initiate long-term tube feeding. This report critically synthesizes the evidence regarding the impact of percutaneous endoscopic gastrostomy (PEG) tube placement on survival in older persons.

METHODS

A systematic search was conducted using MEDLINE from January 1980 until January 1999. Articles reporting survival data in older persons (mean or median age >65 years) after PEG tube placement were identified. The number and age of subjects, length of follow-up, setting, and survival data were extracted from all eligible studies. Mortality data at 1, 2, 6, and 12 months after PEG placement were quantitatively synthesized. Clinical characteristics associated with decreased survival among subjects with PEG tubes were identified.

RESULTS

Five cohort studies compared survival in patients with and without feeding tubes in nursing homes, but none demonstrated a survival benefit. Another cohort study reported increased survival for tube-fed patients with amyotrophic lateral sclerosis. The pooled proportion of all subjects surviving after PEG placement was as follows: 1 month = 0.81 (95% confidence interval [CI], 0.74-0.88), 2 months = 0.70 (95% CI, 0.65-0.74), 6 months = 0.56 (95% CI, 0.20-0.92), and 12 months = 0.38 (95% CI, 0.26-0.49). Advanced age and malignancy were the factors most often reported to be associated with poorer survival among subjects with PEG tubes.

CONCLUSIONS

The impact of PEG placement on survival is not known because the level of evidence is limited. PEG tubes may prolong life in selected populations. However, the majority of older patients selected for PEG placement will not survive 1 year after the procedure. Certain factors may identify those patients more likely to derive a survival benefit from long-term tube feeding. This information may offer some guidance to decision makers for whom prolongation of life is an important factor in the tube-feeding decision.

A retrospective comparison of abdominal muscle strength following breast reconstruction with a free TRAM or DIEP flap

Abdominal weakness is a known potential complication of breast reconstruction with a pedicled or free TRAM flap. It has been presumed that the DIEP flap, which involves no muscle resection, does not compromise abdominal muscle strength but little objective research exists to substantiate this. The aims of this retrospective study were to compare abdominal muscle strength following free TRAM flap and DIEP flap, to compare both groups with a control group and to establish the effect of both procedures on functional activities. Fifty women (23 with a DIEP flap, 27 with a free TRAM flap) plus 32 non-operated controls underwent assessment of their abdominal and back extensor muscle strength on a KIN COM isokinetic dynamometer. Two questionnaires were used to establish the impact on function. The TRAM flap group had significant weakness of the abdominal and back extensor muscles compared with the DIEP flap group and the control group. The trend was for the DIEP flap group to have weaker abdominal muscles than the control group. There was a higher level of abdominal pain and a greater number of reported functional difficulties in the TRAM flap group than in the DIEP flap group. This study demonstrates that whilst the DIEP flap can reduce the strength deficit caused by the free TRAM flap, abdominal weakness can still result from the DIEP flap. A randomised controlled trial is currently underway to investigate the effect of preoperative abdominal exercises in preventing/minimising postoperative abdominal muscle weakness in this group.

Migration of polyethylene particles around stable implants in an animal model

The aim of this study was to test the hypothesis that a tight seal between bone and implant will eliminate the avenue of particle migration around stable implants. Three types of implants were used in rabbits (polished press-fit Ti-6Al-4V or plasma-sprayed hydroxyapatite [HA]-coated Ti-6Al-4V) or doughy stage polymethyl methacrylate (PMMA). Implants were placed in the condylar notch. Each animal received an intra-articular injection of high density polyethylene (PE) particles (10(8) in 0.4 mL; mean size 4.7 microns) at 4 and 6 weeks postoperatively. Eight weeks postoperatively, peri-implant tissues were examined for PE particles and osteolysis. In all cases, intracellular PE particles were seen at the bone-implant interface and within marrow. No osteolysis was observed. Bone apposition was determined by computerized image analysis. There was no significant difference in the percentage of bone apposition (+/- SD) among the three groups of implants: Ti-6Al-4V (68% +/- 19%), HA-coated Ti-6Al-4V (70% +/- 10%), and PMMA (59% +/- 12%). These results indicate that a polished Ti-6Al-4V surface is as effective as PMMA or HA coating in limiting migration of PE particles around stable osseointegrated implants in rabbits.

Tracheal rupture associated with intubation in cats: 20 cases (1996-1998)

OBJECTIVE

To characterize clinical features of tracheal rupture associated with endotracheal intubation in cats and to evaluate the most appropriate treatment for this condition.

DESIGN

Retrospective study.

ANIMALS

20 cats with a history of endotracheal intubation that subsequently developed dyspnea or subcutaneous emphysema.

PROCEDURE

Medical records of cats with a presumptive diagnosis of tracheal rupture associated with intubation were reviewed. Clinical and clinicopathologic data were retrieved.

RESULTS

Cats were evaluated 5 hours to 12 days after a surgical or medical procedure requiring general anesthesia with intubation had been performed. Fourteen (70%) cats were evaluated after dental prophylaxis. All cats radiographed had pneumomediastinum and subcutaneous emphysema. Eighteen of 19 cats were initially treated medically. Duration of medical treatment for cats that did not have surgery ranged from 12 to 72 hours. Cats that had surgery received medical treatment 3 to 24 hours prior to the surgical procedure. Medical treatment alone was administered to 15 cats that had moderate dyspnea, whereas surgical treatment was chosen for 4 cats that had severe dyspnea (open-mouth breathing despite treatment with oxygen) or worsening subcutaneous emphysema. Eighteen cats had improvement of clinical signs, 1 cat died after surgery, and 1 cat died before medical or surgical intervention.

CONCLUSIONS AND CLINICAL RELEVANCE

Most cats with tracheal rupture associated with intubation can be treated medically. Cats with worsening clinical signs (severe dyspnea, suspected pneumothorax, or worsening subcutaneous emphysema) should have surgery performed immediately to correct the defect.

The association between parkinsonism, Alzheimer's disease, and mortality: a comprehensive approach

BACKGROUND

The impact of parkinsonism on survival in older persons independent of dementia is not well understood.

METHODS

Participants in the clinical examination of the Canadian Study of Health and Aging who had parkinsonism and were older than age 65 were identified. The impact of parkinsonism on 5-year survival was determined for a combined cohort with and without dementia, and a stratified analysis was then conducted for the subgroups with Alzheimer's disease (AD) and those without dementia. Subjects with a previous diagnosis of Parkinson's disease and those prescribed drugs causing extrapyramidal side effects were excluded.

FINDINGS

A total of 721 subjects with AD and 1705 subjects without dementia were examined. After adjusting for age and residential status (community vs institution), parkinsonism was associated with poorer survival in the combined cohort (risk ratio 1.51; 95% CI, 1.22-1.85), in those with AD (risk ratio 1.34; 95% CI, 1.02-1.76), and those without dementia (risk ratio 1.54; 95% CI, 1.11-2.15). In the combined cohort, parkinsonism remained independently associated with higher mortality after adjusting for AD status (risk ratio 1.39; 95% CI, 1.13-1.72). In the subgroup with AD, parkinsonism remained associated with poorer survival after adjusting for severity of cognitive impairment (risk ratio 1.33; 95% CI. 1.04-1.74).

INTERPRETATION

Parkinsonism is significantly associated with poorer survival in older persons, regardless of whether they have dementia.

A cross-national survey of tube-feeding decisions in cognitively impaired older persons

OBJECTIVES

Many factors affect the decision to institute long-term tube-feeding in older persons. The objectives of this cross-national survey are to examine the tube-feeding decision-making process for cognitively impaired older persons from the perspective of the substitute decision-makers (SDM) and to contrast this process in US and Canadian healthcare settings.

DESIGN

Survey.

SETTING

Chronic care facilities in Ottawa and nursing homes in Boston.

PARTICIPANTS

Patients more than age 65 who were tube-fed for at least 2 months and who were unable to make their own healthcare decisions at the time of tube placement were identified at both sites. The SDMs of 46 patients in Ottawa and 48 patients in Boston were surveyed.

MEASUREMENTS

The survey asked questions relating to the following categories: health status of the patient, advance directives, communication with the healthcare team, perceived goals of tube-feeding, decision satisfaction, and sociodemographic data.

RESULTS

Tube-fed patients in Boston were more likely to have a diagnosis of dementia than those in Ottawa (60.4% vs 10.9%, P < .001) and were less likely to have had an acute neurological event (35.4% vs 71.7%, P < .001). There was a greater likelihood in Boston than in Ottawa (68.7% vs 6.5%, P < .001) for tube-feeding decisions to be made in a nursing home (vs an acute hospital). In the combined cohort, 19.1% of patients had a living will, and only 47.9% of SDMs felt confident that the patients would want to have a feeding tube. The majority of SDMs at both sites felt they understood the benefits (83.0%), but not the risks (48.9%), of tube-feeding. The most commonly perceived reasons for tube-feeding were to "prolong life" (84.0%) and to "prevent aspiration" (67.0%). Approximately half of all SDMs felt they had received adequate support from the healthcare team. A minority of SDMs (38.3%) at both sites stated that they would want a feeding tube for themselves, and only 40% of SDMs felt the feeding tube had improved the patients' quality of life.

CONCLUSIONS

A greater proportion of patients have feedings tubes inserted because of a degenerative dementia in Boston compared with an acute neurological event in Ottawa. Despite the difference in diagnostic indication for tube-feeding, the substitute decision-making process was seriously limited at both sites by poor implementation of the principle of substituted judgement, a need for broader advance directives, and improved transfer of knowledge between clinicians and decision-makers.

Patterns of outcome measurement in Parkinson's disease clinical trials

The study examines the pattern of use and clinimetric properties of clinical endpoints used in randomized trials for Parkinson's disease (PD). Randomized drug trials for PD were identified through a Medline search conducted from January 1966 until August 1998. The endpoints used in these trials were abstracted. Reports examining the clinimetric properties of the disease-specific scales used in these trials were also abstracted. Data regarding the consistency, accuracy, discrimination and feasibility of scales used in at least 10% of trials were determined. One hundred and thirty-seven articles met the inclusion criteria; 70.8% of trials used some clinical scale for PD as an endpoint. The Unified Parkinson's Disease Rating Scale (UPDRS) was the most commonly used scale (32.8%). Factors independently associated with the use of the UPDRS included: the study location in the US, mean age of subjects over 62.7 years and publication after 1994. The UPDRS was more thoroughly studied and superior in most clinimetric domains compared to scales developed earlier. Few studies included generic health status (2.9%) or cognitive measures (16.8%) as secondary endpoints. There have been definite improvements in the area of disease-specific measurement in PD trials since the introduction of the UPDRS. The results of studies that used instruments with poor or unreported clinimetric properties should be critically interpreted.

Assessing the quality of newspaper medical advice columns for elderly readers

BACKGROUND

Medical advice columns in newspapers can provide a valuable service by educating the general public about important health-related issues. However, these columns may be harmful if the advice or information given in them is incomplete, inappropriate or misleading. The objective of this study was to assess the safety and appropriateness of advice given to elderly readers of newspapers in medical advice columns.

METHODS

Medical advice columns published in Canadian newspapers in 1995 were identified from a CD-ROM database. The articles that were selected were published in English and contained medical advice pertinent to elderly people about topics that could be found in a textbook of geriatric medicine. Fifty articles, randomly selected from the 109 articles that met these criteria, were independently assessed by 5 geriatricians. A scoring system was used to rate the ability to determine to which population the article applied, how well fact was distinguished from opinion, the degree to which critical issues were addressed, the safety and the appropriateness of the advice. When the kappa statistic for inter-rater agreement was 0.74 or less, a 2-stage Delphi process was used in an attempt to reach consensus.

RESULTS

Agreement (kappa > 0.74) was eventually achieved for 232 (92.8%) of the 250 ratings. In 4 (8%) of the articles there was a high probability that the advice given could be applied to the wrong patient population; in 7 (14%) there was a high probability that opinion might be interpreted as fact; and in 11 (22%) the major critical issues were not identified. Of greatest concern, however, the advice in 25 (50%) of the articles was judged to be inappropriate, and in 14 (28%) advice may have been dangerous and potentially life-threatening.

INTERPRETATION

Although medical advice columns have the potential to improve the health of elderly readers, a significant percentage of these articles contain inappropriate or even potentially dangerous advice.

Decision-making for long-term tube-feeding in cognitively impaired elderly people

BACKGROUND

The decision to start long-term tube-feeding in elderly people is complex. The process by which such decisions are made is not well understood. The authors examined the factors involved in the decision to start long-term tube-feeding in cognitively impaired older people from the perspective of the substitute decision-maker.

METHODS

A telephone survey was administered to the substitute decision-makers of tube-fed patients over 65 years old in chronic care facilities in Ottawa. Subjects were recruited from September 1997 to March 1998. Patients were incapable of making their own decisions about tube-feeding. Data were collected on sociodemographic factors, patients' health status, advance directives, communication between the substitute decision-maker and the health care team, and the decision-maker's perceived goals of tube-feeding and satisfaction with the decision regarding tube-feeding.

RESULTS

Among the 57 cases in which the patient was eligible for inclusion in the study, 46 substitute decision-makers agreed to participate. Most of the patients had not given advance directives, and only 26 substitute decision-makers (56.5%) were confident that the patient would want to be tube-fed. A physician spoke with the substitute decision-maker about tube-feeding for 15 minutes or less in 17 cases (37.0%) and not at all in 13 cases (28.3%). Most of the substitute decision-makers (39 [84.8%]) felt that they understood the benefits of tube-feeding, but less than half (21 [45.7%]) felt that they understood the risks. The prevention of aspiration and the prolongation of life were the medical benefits most often cited as reasons for tube-feeding. Just over half (24 [52.2%]) of the substitute decision-makers felt that they had received adequate support from the health care team in making the decision. Substitute decision-makers of patients less than 75 years old were more likely than those of older patients to feel supported (odds ratio [OR] 4.2, 95% confidence interval [CI] 1.0-17.9). Compared with the physician's making the decision independently, substitute decision-makers felt more supported if they primarily made the decision (OR 16.5, 95% CI 2.7-101.4) or if they made the decision together with the physician (OR 5.3, 95% CI 1.0-27.9). Most (20 [43.5%]) of the substitute decision-makers did not feel that tube-feeding improved the patient's quality of life, and less than half (21 [45.7%]) indicated that they would choose the intervention for themselves.

INTERPRETATION

The substitute decision-making process for tube-feeding in cognitively impaired elderly people is limited by a need for advance directives, lack of confidence in substituted judgement and poor communication of information to the substitute decision-maker by the health care team.

Assessing muscle stiffness from quiet stance in Parkinson's disease

In previous studies, we developed a postural stiffness measure that is extracted from foot center-of-pressure (COP) trajectories from quietly standing individuals and is based on an analytical mechanical model of posture control. Here we apply this measure to patients with Parkinson's disease (PD). We correlated the postural stiffness measure with different clinical rating scales, obtained from patients. Kendall's rank correlation was highly significant between the stiffness measure and rigidity, bradykinesia, posture impairment, gait, and leg agility, respectively, as rated by the Unified Parkinson's Disease Rating Scale. These results provide further evidence that a higher intrinsic muscle stiffness may contribute to the aforementioned clinically defined symptoms. From a clinical standpoint, this work indicates that the proposed postural stiffness measure may be useful as an assessment tool for the evaluation of PD patients subsequent to pharmacological and surgical treatment.

Radiologic diagnosis and staging of head and neck squamous cell carcinoma

The predominant extracranial head and neck cancer in adults is squamous cell carcinoma. The purpose of this article is to discuss the radiographic evaluation of these patients with CT scans or MR imaging before therapeutic intervention. Specific focus is given to the efficacy of CT scans and MR imaging, as an adjunct to clinical staging for evaluation of the primary tumor, and metastatic adenopathy. MR imaging, because of its improved soft tissue contrast and multiplanar capability, is probably superior to CT scans for evaluation of the primary tumor in patients with squamous cell carcinoma. CT scans, however, remain the gold standard for identifying metastatic adenopathy and in most institutions remain the study of choice for evaluating this patient population.

Does artificial enteral nutrition prolong the survival of institutionalized elders with chewing and swallowing problems?

BACKGROUND

There is a lack of prognostic data regarding tube feeding of institutionalized elderly people. The objective of this study was to determine the impact of feeding tubes on the survival of nursing home residents with chewing and swallowing problems, and to follow the course of the tube-fed residents over one year.

METHODS

We conducted a cohort study with 12-month follow-up using Minimum Data Set resident assessments from 1991. Participants included 5,266 nursing home residents over the age of 65 with chewing and swallowing problems living in 272 Washington state nursing homes. Residents who had a feeding tube were identified. Baseline clinical characteristics and 12-month survival were compared for residents with and without feeding tubes. The proportion of tube-fed residents who became tube-free during the follow-up period was determined, and clinical features that predicted this outcome were examined.

RESULTS

Among the residents with chewing and swallowing problems, 10.5% had a feeding tube. After adjusting for potential confounding covariates, tube-fed residents had a significantly higher one-year mortality rate than those without feeding tubes (risk ratio, 1.44; 95% CI, 1.17-1.76). Of the 430 residents with feeding tubes who survived the follow-up period, 25.1% became free of a feeding tube. Age less than 87 years was associated with a significantly greater likelihood of becoming tube-free (odds ratio, 1.66; 95% CI, 1.03-2.6).

CONCLUSIONS

Residents selected for feeding tube placement have poorer survival after one year than residents who are not tube-fed. However, the feeding tubes are removed in a significant proportion of residents who survive one year. Residents with a potentially reversible condition, for whom the feeding tubes are a temporary intervention, need to be identified.

Interaction of stress, smoking, and dietary restraint in women

Smoking cessation often results in weight gain but certain subtypes of smokers may be more likely than others to gain weight. Women high in dietary restraint ("restrainers") increase food intake and gain more weight than nonrestrainers during smoking cessation. Restrainers have also been reported to increase food intake following laboratory stressors. Therefore, the present study was designed to measure the influence of stress on food intake and subjective distress during acute smoking abstinence in restrained and nonrestrained women. Participants were 48 women, 18-40 years old, comprising six groups (n = 8 per group) in a 2 x 3 x 2 design. Groups consisted of two levels of restraint (restrained and nonrestrained) and three levels of smoking (ad lib. smokers, abstinent smokers, and nonsmokers), whereas the within-participant manipulation involved two sessions differing in stress (stress and control). Snack foods were available for consumption. Results showed that distress, measured by the Stress-Arousal Checklist and visual analogue measures of tension and anxiety, was higher in the stress session for all groups except for restrainers who smoked ad lib. Furthermore, distress was significantly higher in smoke-abstinent restrainers during the stress session than all other conditions. However, despite differences in distress, no effect was observed for food intake. Desire for a cigarette showed a sharper increase over the stress session for restrainers compared with nonrestrainers but did not differ in the control session. These data suggest that restrainers may use smoking to reduce distress and may increase smoking, but not eating, during stress.

Exclusion of elderly subjects from clinical trials for Parkinson disease

OBJECTIVES

To determine whether subjects older than 75 years are included in the randomized controlled trials of antiparkinsonian medications conducted during the last 30 years and to identify study characteristics that are associated with the exclusion of patients of advanced age.

METHODS

A systematic search was conducted on MEDLINE from January 1966 until September 1996 of all randomized controlled trials of drugs used to treat the motor symptoms of Parkinson disease. Articles were abstracted for the age of subjects date of publication, geographic location, drug class studied, stage of Parkinson disease of subjects, and the number of subjects in each trial.

RESULTS

One hundred twelve articles met the inclusion criteria. The weighted mean (+/- SD) age for subjects in all trials was 62.2 +/- 3.9 years. Forty-two studies (37.5%) included subjects older than 75 years. However, in 31 articles (27.7%) it could not be determined if subjects older than 75 years were included. Among the 8 studies that provided the actual number of subjects within specific age groups, only 8 (5.5%) of 145 subjects were older than 75 years. Publication in the last decade was significantly associated with a decreased likelihood of including subjects older than 75 years (odds ratio, 0.19; 95% confidence interval, 0.06-0.62).

CONCLUSIONS

The relatively small number of subjects older than 75 years included in controlled trials of antiparkinsonian drugs seriously impedes our understanding of the efficacy and safety of these drugs in a large subgroup of frail patients for whom these products are prescribed. The tendency to exclude subjects of advanced age is highest in the most recently published articles that study new advances in pharmacotherapy. There is inadequate reporting of the age characteristics of subjects in clinical trials. This limitation hinders the synthesis of data regarding drug efficacy and toxicity relevant to older age groups.

Increased gait unsteadiness in community-dwelling elderly fallers

OBJECTIVE

To test the hypothesis that quantitative measures of gait unsteadiness are increased in community-dwelling elderly fallers.

STUDY DESIGN

Retrospective, case-control study.

SETTING

General community.

PARTICIPANTS

Thirty-five community-dwelling elderly subjects older than 70 years of age who were capable of ambulating independently for 6 minutes were categorized as fallers (age, 82.2 +/- 4.9 yrs [mean +/- SD]; n = 18) and nonfallers (age, 76.5 +/- 4.0 yrs; n = 17) based on history; 22 young (age, 24.6 +/- 1.9 yrs), healthy subjects also participated as a second reference group.

MAIN OUTCOME MEASURES

Stride-to-stride variability (standard deviation and coefficient of variation) of stride time, stance time, swing time, and percent stance time measured during a 6-minute walk.

RESULTS

All measures of gait variability were significantly greater in the elderly fallers compared with both the elderly nonfallers and the young subjects (p < .0002). In contrast, walking speed of the elderly fallers was similar to that of the nonfallers. There were little or no differences in the variability measures of the elderly nonfallers compared with the young subjects.

CONCLUSIONS

Stride-to-stride temporal variations of gait are relatively unchanged in community-dwelling elderly nonfallers, but are significantly increased in elderly fallers. Quantitative measurement of gait unsteadiness may be useful in assessing fall risk in the elderly.

The risk factors and impact on survival of feeding tube placement in nursing home residents with severe cognitive impairment

BACKGROUND

The provision of artificial enteral nutrition to an aged person with severe cognitive impairment is a complex dilemma in the long-term care setting.

OBJECTIVE

To determine the risk factors and impact on survival of feeding tubes in nursing home residents with advanced cognitive impairment.

METHODS

We conducted a cohort study with 24-month follow-up using Minimum Data Set resident assessments on 1386 nursing home residents older than 65 years with recent progression to severe cognitive impairment in the state of Washington. Residents within this population who underwent feeding tube placement were identified. Clinical characteristics and survival for a period of 24 months were compared for residents who were and were not tube fed.

RESULTS

Among the residents with recent progression to severe cognitive impairment, 9.7% underwent placement of a feeding tube. Factors independently associated with feeding tube placement included age younger than 87 years (odds ratio [OR], 1.85; 95% confidence interval [CI], 1.25-2.78), aspiration (OR, 5.46; 95% CI, 2.66-11.20), swallowing problems (OR, 3.00; 95% CI, 1.81-4.97), pressure ulcer (OR, 1.64; 95% CI, 1.23-2.95), stroke (OR, 2.12; 95% CI, 1.17-2.62), less baseline functional impairment (OR, 2.07; 95% CI, 1.27-3.36), no do-not-resuscitate order (OR, 3.03; 95% CI, 1.92-4.85), and no dementia (OR, 2.17; 95% CI, 1.43-3.22). Survival did not differ between groups of residents with and without feeding tubes even after adjusting for independent risk factors for feeding tube placement.

CONCLUSIONS

There are specific risk factors associated with feeding tube placement in nursing home residents with severe cognitive impairment. However, there is no survival benefit compared with similar residents who are not tube fed. These prognostic data are important for health care providers, families, and patients making decisions regarding enteral nutritional support in long-term care.

Altered fractal dynamics of gait: reduced stride-interval correlations with aging and Huntington's disease

Fluctuations in the duration of the gait cycle (the stride interval) display fractal dynamics and long-range correlations in healthy young adults. We hypothesized that these stride-interval correlations would be altered by changes in neurological function associated with aging and certain disease states. To test this hypothesis, we compared the stride-interval time series of 1) healthy elderly subjects and young controls and of 2) subjects with Huntington's disease and healthy controls. Using detrended fluctuation analysis we computed alpha, a measure of the degree to which one stride interval is correlated with previous and subsequent intervals over different time scales. The scaling exponent alpha was significantly lower in elderly subjects compared with young subjects (elderly: 0.68 +/- 0.14; young: 0.87 +/- 0.15; P < 0.003). The scaling exponent alpha was also smaller in the subjects with Huntington's disease compared with disease-free controls (Huntington's disease: 0.60 +/- 0.24; controls: 0.88 +/-0.17; P < 0.005). Moreover, alpha was linearly related to degree of functional impairment in subjects with Huntington's disease (r = 0.78, P < 0.0005). These findings demonstrate that strike-interval fluctuations are more random (i.e., less correlated) in elderly subjects and in subjects with Huntington's disease. Abnormal alterations in the fractal properties of gait dynamics are apparently associated with changes in central nervous system control.

Changes in taste and satiety in dietary-restrained women following stress

Stress has been shown to increase food consumption in women with high levels of dietary restraint (restrainers) but decrease consumption in nonrestrainers. The present study was designed to replicate the differential eating pattern following stress and measure physiological and subjective responses to food over repeated taste presentations. Restrained (N = 16) and nonrestrained (N = 16) women were given eight taste presentations of a food followed by an ad lib taste test. Between taste trials, half of the restrainers and nonrestrainers performed a variation of the Stroop stressor while remaining subjects sat quietly. Salivation to the food cue was measured at each trial as well as ratings of food liking, hunger, fullness, and arousal. Results showed significant effects of restraint on food liking and stress condition on hunger. Restrainers increased liking ratings over taste trials whereas ratings for nonrestrainers increased and then decreased to baseline levels by the last trial (p = 0.05). Nonstressed subjects showed an increase in hunger ratings, whereas ratings for stressed subjects did not show any stable directional pattern (p = 0.04). Salivary responses decreased for all groups (p = 0.01). A significant interaction of restraint by stress for intake was found (p = 0.03); restrainers increased consumption following stress whereas nonrestrainers decreased consumption as compared with controls. The data suggest that the Stroop task can influence intake in restrainers, but the changes in intake did not directly correspond to the changes observed during the presentations of the taste cues and stressor.