A prospective randomized trial examining the use of a closed suction drain shows no influence on strength or function in primary total knee arthroplasty.

AIMS: The aim of this study was to determine whether closed suction drain (CSD) use influences recovery of quadriceps strength and to examine the effects of drain use on secondary outcomes: quadriceps activation, intra-articular effusion, bioelectrical measure of swelling, range of movement (ROM), pain, and wound healing complications. PATIENTS AND METHODS: A total of 29 patients undergoing simultaneous bilateral total knee arthroplasty (TKA) were enrolled in a prospective, randomized blinded study. Patients were randomized to receive a CSD in one limb while the contralateral limb had the use of a subcutaneous drain (SCDRN) without the use of suction ('sham drain'). Isometric quadriceps strength was collected as the primary outcome. Secondary outcomes consisted of quadriceps activation, intra-articular effusion measured via ultrasound, lower limb swelling measured with bioelectrical impendence and limb girth, knee ROM, and pain. Outcomes were assessed preoperatively and postoperatively at day two, two and six weeks, and three months. Differences between limbs were determined using paired Student's t-tests or Wilcoxon's signed-rank tests. RESULTS: No significant differences were identified between limbs prior to surgery for the primary or secondary outcomes. No significant differences in quadriceps strength were seen between CSD and SCDRN limbs at postoperative day two (p = 0.09), two weeks (primary endpoint) (p = 0.7), six weeks (p = 0.3), or three months (p = 0.5). The secondary outcome of knee extension ROM was significantly greater in the CSD limb compared with the SCDRN (p = 0.01) at two weeks following surgery, but this difference was absent at all other intervals. Secondary outcomes of quadriceps activation, intra-articular effusion, lower limb swelling, and pain were not found to differ significantly at any timepoint following surgery. CONCLUSION: The use of CSD during TKA did not influence quadriceps strength, quadriceps activation, intra-articular effusion, lower limb swelling, ROM, or pain. These results have limited drain use by the authors in primary uncomplicated TKA. Cite this article: Bone Joint J 2019;101-B (7 Supple C):84-90.

Medical student clerkship performance and career selection after a junior medical student surgical mentorship program.

BACKGROUND: The impact of early medical school mentorship in students' clerkships performance and career selection is unknown. METHODS: We administered Introduction to Surgery, a resident-directed, semester-long, preclinical elective to junior medical students who answered a Likert-type survey after residency application. Elective participants (EPs) were compared with nonparticipant applicants (EAs), medical school class (MS), and national match outcomes (USA). RESULTS: All 18 EPs (7 M1's, 11 M2's) completed the elective and survey. EP reported more confidence and improved surgical skills, especially attributed to resident mentorship (F(13,237) = 2.3, P = 8*10(-3)). EP "honored" the clerkship more than MS (P = .05); 55.6% of EP, 37.5% of EA, and 27.7% of MS chose surgical fields, yielding a relative risk of 2.0 for EP vs MS (95% confidence interval: 1.3 to 3.2, P = 4*10(-3)). EP "strongly agree" with future mentorship programs (4.6/5), and 1 EP reported the course to be the "main reason" for applying to general surgery. CONCLUSIONS: Introduction to Surgery provides a model for a multifaceted junior medical student mentorship program, which has the potential to retain interested students for surgical career selection.

Clinical and molecular delineation of the 17q21.31 microdeletion syndrome.

BACKGROUND: The chromosome 17q21.31 microdeletion syndrome is a novel genomic disorder that has originally been identified using high resolution genome analyses in patients with unexplained mental retardation. AIM: We report the molecular and/or clinical characterisation of 22 individuals with the 17q21.31 microdeletion syndrome. RESULTS: We estimate the prevalence of the syndrome to be 1 in 16,000 and show that it is highly underdiagnosed. Extensive clinical examination reveals that developmental delay, hypotonia, facial dysmorphisms including a long face, a tubular or pear-shaped nose and a bulbous nasal tip, and a friendly/amiable behaviour are the most characteristic features. Other clinically important features include epilepsy, heart defects and kidney/urologic anomalies. Using high resolution oligonucleotide arrays we narrow the 17q21.31 critical region to a 424 kb genomic segment (chr17: 41046729-41470954, hg17) encompassing at least six genes, among which is the gene encoding microtubule associated protein tau (MAPT). Mutation screening of MAPT in 122 individuals with a phenotype suggestive of 17q21.31 deletion carriers, but who do not carry the recurrent deletion, failed to identify any disease associated variants. In five deletion carriers we identify a <500 bp rearrangement hotspot at the proximal breakpoint contained within an L2 LINE motif and show that in every case examined the parent originating the deletion carries a common 900 kb 17q21.31 inversion polymorphism, indicating that this inversion is a necessary factor for deletion to occur (p<10(-5)). CONCLUSION: Our data establish the 17q21.31 microdeletion syndrome as a clinically and molecularly well recognisable genomic disorder.

The extended trochanteric osteotomy in revision hip arthroplasty: a critical review of 166 cases at mean 3-year, 9-month follow-up.

We conducted a retrospective review of 192 consecutive revision hip arthroplasties with an extended proximal femoral osteotomy performed from 1992 through January 1998. Of these osteotomies, 166 had a minimum of 2 years of clinical and radiographic follow-up (range, 2-7.5 years; average, 3 years, 9 months). All patients had a femoral reconstruction with an extended trochanteric osteotomy and an extensively porous-coated, cementless femoral component. The average age at revision was 65.8 years (range, 26-84 years). Of the 166 osteotomies, 2 nonunions (1.2%) and 1 malunion (0.6%) were identified. Seventeen hips (10.2%) required reoperation. Pain and walking scores improved from a mean of 6.5 preoperatively to 9.8 postoperatively. The extended trochanteric osteotomy heals predictably and enhances the surgeons' ability to address many difficult issues encountered in revision arthroplasty.

Surveying Saccharomyces genomes to identify functional elements by comparative DNA sequence analysis.

Comparative sequence analysis has facilitated the discovery of protein coding genes and important functional sequences within proteins, but has been less useful for identifying functional sequence elements in nonprotein-coding DNA because the relatively rapid rate of change of nonprotein-coding sequences and the relative simplicity of non-coding regulatory sequence elements necessitates the comparison of sequences of relatively closely related species. We tested the use of comparative DNA sequence analysis to aid identification of promoter regulatory elements, nonprotein-coding RNA genes, and small protein-coding genes by surveying random DNA sequences of several Saccharomyces yeast species, with the goal of learning which species are best suited for comparisons with S. cerevisiae. We also determined the DNA sequence of a few specific promoters and RNA genes of several Saccharomyces species to determine the degree of conservation of known functional elements within the genome. Our results lead us to conclude that comparative DNA sequence analysis will enable identification of functionally conserved elements within the yeast genome, and suggest a path for obtaining this information.

Outcomes of external fixation of pediatric femoral shaft fractures.

Thirty-seven femoral shaft fractures, in 33 patients, were treated with unilateral external fixation after reduction from 1992 through 1998. Ten girls and 23 boys ranged in age from 4 to 14 years. Thirteen children had multiple injuries, whereas 20 children had isolated fractures. Average follow-up was 3 years, 9 months, with only five children lost to follow-up. The average duration in fixator was 107 days. Thirty-six of 37 fractures healed, and there was one delayed union. There was minimal angulation, and limb-length inequality was generally <1 cm; 72.7% had pin-tract infections. Eight (21.6%) patients refractured; four occurred in the four patients with bilateral femur fractures. We agree with previous reports that external fixation remains a viable option for treatment of pediatric femoral shaft fractures. However, in our series, rate of refracture (21.6%) after removal of the external fixator is significantly higher than previously reported in literature. Children with bilateral femur fractures were at greatest risk.

Comparative genomic sequence analysis of the human and mouse cystic fibrosis transmembrane conductance regulator genes.

The identification of the cystic fibrosis transmembrane conductance regulator gene (CFTR) in 1989 represents a landmark accomplishment in human genetics. Since that time, there have been numerous advances in elucidating the function of the encoded protein and the physiological basis of cystic fibrosis. However, numerous areas of cystic fibrosis biology require additional investigation, some of which would be facilitated by information about the long-range sequence context of the CFTR gene. For example, the latter might provide clues about the sequence elements responsible for the temporal and spatial regulation of CFTR expression. We thus sought to establish the sequence of the chromosomal segments encompassing the human CFTR and mouse Cftr genes, with the hope of identifying conserved regions of biologic interest by sequence comparison. Bacterial clone-based physical maps of the relevant human and mouse genomic regions were constructed, and minimally overlapping sets of clones were selected and sequenced, eventually yielding approximately 1.6 Mb and approximately 358 kb of contiguous human and mouse sequence, respectively. These efforts have produced the complete sequence of the approximately 189-kb and approximately 152-kb segments containing the human CFTR and mouse Cftr genes, respectively, as well as significant amounts of flanking DNA. Analyses of the resulting data provide insights about the organization of the CFTR/Cftr genes and potential sequence elements regulating their expression. Furthermore, the generated sequence reveals the precise architecture of genes residing near CFTR/Cftr, including one known gene (WNT2/Wnt2) and two previously unknown genes that immediately flank CFTR/Cftr.

Sentinel lymph node biopsy for breast cancer: the role of previous biopsy on patient eligibility.

Several reports have demonstrated the accurate prediction of axillary nodal status with radiolocalization and selective resection of sentinel lymph nodes (SLNs) in patients with breast cancer (BC). Because of concerns over lymphatic disruption, several authors have proposed that prior excisional breast biopsy is a contraindication for SLN biopsy. Clear unfiltered 99mtechnetium-sulfur colloid (1.0 mCi) was injected around the perimeter of the breast lesion (palpable and nonpalpable) or prior biopsy site. Resection of the radiolocalized SLN was then performed. Axillary lymph node dissection was performed immediately after SLN biopsy in the first 57 patients. Eighty-two BC patients underwent SLN biopsy. The SLN was localized in 98 per cent (80 of 82). The type of previously performed diagnostic biopsy or the location of the primary lesion did not influence the ability to localize the sentinel lymph node. In the 57 patients who had axillary lymph node dissection, metastatic disease was identified in 23 per cent (13 of 57). Axillary nodal status was accurately predicted in 98 per cent (56 of 57). Early experience with radiolocalization and selective resection of SLN in BC remains promising. By demonstrating the effective localization of the SLN regardless of the extent of prior biopsy, these data support expanding the number of patients potentially eligible for SLN biopsy.

Neutrophil priming state predicts capillary leak after gut ischemia in rats.

BACKGROUND: Multiple organ failure after serious injury or illness is a major determinant of mortality. An initial insult is believed to "prime" circulating neutrophils and induce systemic inflammation. Thereafter, a second insult will precipitate distant organ injury. The aim of these studies was to evaluate circulating neutrophil function after mesenteric ischemia-reperfusion to determine the neutrophil "priming state," a quantitative and clinically useful predictor of multiple organ failure. MATERIALS AND METHODS: Anesthetized Sprague-Dawley rats underwent superior mesenteric artery occlusion for 30 min or sham operation and were euthanized after 2, 6, or 24 h of reperfusion. Control animals had blood taken without any intervention. To determine changes in lung capillary permeability, another group of rats received Evan's blue, a dye that binds albumin, 1 h before sacrifice. Flow cytometric analysis was performed on 5 million white blood cells after removal of red cells by lysis and centrifugation. Neutrophil number, oxidative burst, and CD18 expression were measured. RESULTS: The number of circulating neutrophils was elevated similarly in rats subjected to sham operation or ischemia-reperfusion. Oxidative burst potential was increased at 2 h, maximum at 6 h, and normal at 24 h after reperfusion, but not in sham rats. CD18 expression was similar in all groups. There was a significant temporal correlation between the "priming state" of the circulating neutrophil, defined as the product of the neutrophil number times oxidative burst, and lung leak. CONCLUSIONS: The neutrophil "priming state" may allow the clinician to better predict those patients at greatest risk for multiple organ failure.

Decision making on surgical palliation based on patient outcome data.

BACKGROUND: Strategies for the effective application of palliative procedures are infrequently standardized and incompletely understood. The effect on patient outcome as determined by elements such as resolution of chief complaints, quality of life, pain control, morbidity of therapy, and resource utilization should predominate decisions regarding surgical palliative care. METHODS: Articles published between 1990 and 1996 on the surgical palliation of cancer were identified by a MEDLINE search and reviewed for designated parameters considered important for good palliative care. RESULTS: A total of 348 citations were included. Entries considered these fundamental elements: cost (2%); pain control (12%); quality of life (17%); need to repeat the intervention (59%); morbidity and mortality (61 %); survival (64%); and physiologic response (69%). Established methods for quality of life and pain assessment were sporadically utilized. CONCLUSIONS: In the current surgical literature, there is uncommon reporting of the range of data required to recommend sound palliative surgical choices.

Ischemia-reperfusion protects the rat small intestine against subsequent injury.

BACKGROUND: It has been suggested that multiple sublethal insults are commonly associated with the development of multiple organ failure (MOF). The gut is considered to be pivotal in the pathogenesis of MOF. This study investigated the effects of repeated ischemia-reperfusion of the rat small intestine. METHODS: Groups of rats underwent 30 min of superior mesenteric artery occlusion or sham operation followed by 24 h of reperfusion. They then received an additional 30 min of superior mesenteric artery occlusion and 2 h of reperfusion or sham operation. Small intestine was examined for mucosal injury, neutrophil infiltration, goblet cell number, and generation of the eicosanoids, prostaglandin E2, and leukotriene B4. Activation of neutrophils was assessed in systemic venous blood. RESULTS: Animals subjected to two insults of ischemia-reperfusion demonstrated significantly less mucosal injury than animals undergoing one episode of ischemia and 2 h of reperfusion, despite increased neutrophil infiltration, leukotriene B4, and activated systemic neutrophils. Goblet cell number was elevated in animals 24 h after the first ischemia-reperfusion insult and remained enhanced after the second episode of ischemia-reperfusion. CONCLUSIONS: The initial episode of ischemia-reperfusion caused an adaptive response associated with cytoarchitectural preservation following the subsequent insult. Increased mucus production was associated with mucosal protection. Nevertheless, repeated ischemia-reperfusion potentiated the local inflammatory response and the systemic activation of neutrophils.

Guidelines for the safe use of radioactive materials during localization and resection of the sentinel lymph node.

BACKGROUND: Several reports have demonstrated accurate prediction of nodal metastasis with radiolocalization and selective resection of the radiolocalized sentinel lymph node (SLN) in patients with breast cancer and melanoma. As reliance on this technique grows, its use by those without experience in radiation safety will increase. METHODS: Tissue obtained during radioguided SLN biopsies was examined for residual radioactivity. Specimens with a specific activity greater than the radiologic control level (RCL) of 0.002 microCi/g were considered radioactive. Radiation exposure to the surgical team was measured. RESULTS: A total of 24 primary tissue specimens and 318 lymph nodes were obtained during 57 operations (37 for breast cancer, 20 for melanoma). All 24 (100%) of the specimens injected with radiopharmaceutical and 89 of 98 (91%) of the localized nodes were radioactive after surgery. Activity fell below the RCL 71+/-3.6 hours in primary tissue specimens, 46+/-1.7 hours in nodes from melanoma patients, and 33+/-3.5 hours in nodes from breast cancer patients (P = .037). The hands of the surgical team (n = 22 cases) were exposed to 9.4+/-3.6 mrem/case. CONCLUSION: Although low levels of radiation exposure are associated with radiolocalization and resection of the SLN, the presented guidelines ensure conformity to existing regulations and allow timely pathologic analysis.

The role of speed of processing, inhibitory mechanisms, and presentation order in trail-making test performance.

The roles of speed of processing, inhibition, and presentation order in the Trail Making Test (TMT) performance were examined. One-hundred ten undergraduates performed the TMT (1/2 received order Part A-Part B, 1/2 received order Part B-Part A) and also completed computerized tests of inhibitory functioning and speed of processing. Neither speed of processing nor inhibitory functioning affected TMT performance. However, order of presentation significantly affected TMT performance. Presentation order is an important variable to consider in TMT performance.

Nitric oxide mediates acute lung injury by modulation of inflammation.

Nitric Oxide's (NO) function in vasomotor control, inflammation, and signal transduction makes it an attractive potential mediator of the capillary leak seen in acute lung injury. Despite extensive study, the role of NO in intestinal ischemia/reperfusion-induced capillary leak remains controversial. Rats were treated with vehicle, norepinephrine, or L-NNA (nitric oxide synthase inhibitor) and then underwent sham laparotomy or 30 min SMA occlusion followed by 1 to 12 h of reperfusion. Evan's Blue dye was administered 1 h before animals were euthanized. Ratios of bronchoalveolar lavage or small-intestine lavage to serum dye concentrations were calculated as measures of capillary leak. Circulating neutrophil activation was measured with a nitroblue tetrazolium reduction assay. In vehicle-treated animals, both capillary leakage and PMN activation peaked at 4 h of reperfusion. These parameters returned to baseline by 12 h. Treatment with L-NNA accelerated ischemia/reperfusion-induced PMN activation as well as accelerated capillary leak from 4 to 1 h. Treatment with norepinephrine (hypertensive control) increased the magnitude of lung capillary leak but had no effect on the timing of ischemia/reperfusion-induced PMN activation or ischemia/reperfusion-induced capillary leak. These data show that intestinal ischemia/reperfusion-induced systemic capillary leak is associated with systemic neutrophil activation. Nitric oxide synthase inhibition accelerates ischemia/reperfusion-induced capillary leak and mediates the capillary leak seen in acute lung injury by modulating neutrophil activation.

Ultrasonographically guided injection improves localization of the radiolabeled sentinel lymph node in breast cancer.

BACKGROUND: Several reports have demonstrated the accurate prediction of axillary nodal status (ANS) with radiolocalization and selective resection of sentinel lymph nodes (SLN) in breast cancer. To date, no technique has proven to be superior in localizing the SLN. METHODS: 1.0 mCi of clear unfiltered 99mtechnetium sulfur colloid was injected under ultrasonographic (US) guidance around the perimeter of the breast lesion (palpable and nonpalpable) or previous biopsy site. Resection of the radiolocalized nodes was performed, followed by complete axillary lymph node dissection (AXLND). RESULTS: Forty-two breast cancer patients underwent SLN biopsy after US-guided radiopharmaceutical injection. The SLN was localized in 41 patients (98%). The type of previously performed diagnostic biopsy did not influence the ability to localize the sentinel lymph node. Pathology revealed nodal metastasis in 7 of the 41 evaluable patients (17%). ANS was accurately predicted in 40 of 41 patients (98%). CONCLUSIONS: Early experience with radiolocalization and selective resection of SLN in breast cancer remains promising. Use of US-guided injection facilitates localization of the SLN, perhaps as a result of more accurate placement of the radionuclide marker. Use of this technique allowed for effective management of patients regardless of tumor size or the extent of prior biopsy, thereby expanding the potential number of eligible patients for SLN biopsy.

Fighting the symptoms of merger mania.

Hospital mergers and acquisitions create uncertainty and confusion among philanthropists. How can we reassure them about the future use of their gifts?

Effect of internal mammary harvest on postoperative pain and pulmonary function.

Forty-three patients undergoing median sternotomy were evaluated for postoperative pain and pulmonary function. Group 1 (n = 26) had harvest of the internal mammary artery (IMA) and group 2 (n = 17) did not. Postoperative pain and pulmonary function were evaluated on the fifth postoperative day. Both groups showed a decrease in forced expiratory volume in 1 second (group 1, 44%; group 2, 39%), but there was no significant difference in the loss between the two groups (p = 0.32). Using a numeric rating scale, there was significant increase in postoperative pain in group 1 (group 1, 6.35; group 2, 3.82; p = 0.0002). There is a suggestion that internal mammary artery harvesting itself worsens postoperative pulmonary function tests, and this may be related to a significant increase in postoperative pain.