Recommendations on prevention and screening for colorectal cancer in Hong Kong.

Colorectal cancer is the commonest cancer in Hong Kong. The Cancer Expert Working Group on Cancer Prevention and Screening was established in 2002 under the Cancer Coordinating Committee to review local and international scientific evidence, assess and formulate local recommendations on cancer prevention and screening. At present, the Cancer Expert Working Group recommends that average-risk individuals aged 50 to 75 years and without significant family history consult their doctors to consider screening by: (1) annual or biennial faecal occult blood test, (2) sigmoidoscopy every 5 years, or (3) colonoscopy every 10 years. Increased-risk individuals with significant family history such as those with a first-degree relative diagnosed with colorectal cancer at age ≤60 years; those who have more than one first-degree relative diagnosed with colorectal cancer irrespective of age at diagnosis; or carriers of genetic mutations associated with familial adenomatous polyposis or Lynch syndrome should start colonoscopy screening earlier in life and repeat it at shorter intervals.

Recommendations on prevention and screening for breast cancer in Hong Kong.

In Hong Kong, breast cancer is the most common cancer among women and poses a significant health care burden. The Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) was set up in 2002 by the Cancer Coordinating Committee to review and assess local and international scientific evidence, and to formulate recommendations for cancer prevention and screening. After considering the local epidemiology, emerging scientific evidence, and local and overseas screening practices, the CEWG concluded that it was unclear whether population-based breast cancer screening did more harm than good in local asymptomatic women at average risk. The CEWG considers that there is insufficient evidence to recommend for or against population-based mammography screening for such individuals. Women who consider breast cancer screening should be adequately informed about the benefits and harms. The CEWG recommends that all women adopt primary preventive measures, be breast aware, and seek timely medical attention for suspicious symptoms. For women at high risk of breast cancer, such as carriers of confirmed BRCA1/2 deleterious mutations and those with a family history of breast cancer, the CEWG recommends that they seek doctor's advice for annual mammography screening and the age at which the process should commence. Additional annual screening by magnetic resonance imaging is recommended for confirmed BRCA1/2 mutation carriers or women who have undergone radiation therapy to the chest between the age of 10 and 30 years. Women at moderate risk of breast cancer should discuss with doctors the pros and cons of breast cancer screening before making an informed decision about mammography screening every 2 to 3 years.

Plastic surgical management of the contralateral breast in post-mastectomy breast reconstruction.

Breast reconstruction following mastectomy can be reliably undertaken using many different techniques. Although excellent cosmetic results can be achieved without contralateral balancing surgery, many unilateral breast reconstructions require a balancing procedure on the contralateral breast in order to achieve symmetry; the ultimate goal in breast reconstruction. This article attempts to summarise the existing literature on the plastic surgical management of the contralateral breast. It also outlines the multifactorial and complex issues involved in the planning and undertaking of such surgery with illustrative examples. The implications for future oncological management and radiological surveillance following the procedure are also discussed in brief.

Pleuropancreatic fistulae: specialist center management.

BACKGROUND AND AIMS: Internal pancreatic fistulae are uncommon sequelae of severe acute pancreatitis. Due to their low prevalence, experience in the management of this condition remains sparse outside specialist centers and management remains controversial. We report our experience with pleuropancreatic fistulae (PPF). PATIENTS: Six patients (three males, median age 34 years [range, 32-74 years]) with PPF were managed in our unit over a 24-month period from April 2006 to April 2008. The etiology of pancreatitis was alcohol (four), gallstones (one), and unknown cause (one). All patients had documented pleural effusions with amylase content >1,000 iu/dl. RESULTS: All patients underwent computerized tomography (CT) and magnetic resonance imaging (MRI) cross-sectional scanning to identify the site of ductal disruption. CT alone was able to identify the disruption in four cases and a combination of CT and MRI localized the ductal disruption in all patients. Five of six patients required ERCP and placement of a pancreatic duct (PD) stent. No patient required pancreatic surgery and all patients remain well at a median follow up of 39 weeks. CONCLUSION: Pleuropancreatic fistulae can present a challenging diagnostic dilemma. A multi-disciplinary approach addressing nutritional support and endotherapy allows successful non-operative resolution within specialist units.

Combined phacoemulsification and nonpenetrating deep sclerectomy in the treatment of chronic angle-closure glaucoma with cataract.

PURPOSE: To review the result of nonpenetrating deep sclerectomy (NPDS) combined with phacoemulsification in the treatment of chronic angle-closure glaucoma (CACG) with coexisting cataract. METHODS: This is a retrospective review of 29 eyes of 26 patients who had undergone combined NPDS and phacoemulsification for cataract and CACG between January 2001 and June 2003. The visual acuity, intraocular pressure (IOP), and complications were analyzed. RESULTS: The mean follow-up period was 33.8 months (range 23.3 to 54.0 months). Postoperative visual acuity improved in 21 eyes (72%) and remained the same in 6 eyes (21%). The IOP was reduced significantly from 20.3+/-3.9 mmHg (mean +/- SD) preoperatively to 15.9+/-3.1 mmHg postoperatively at last follow-up visit (p<0.001). The number of antiglaucoma medications was also reduced significantly from 2.9+/-0.8 (mean +/- SD) preoperatively to 1.0+/-1.2 at last follow-up (p<0.001). Fifteen eyes (52%) achieved complete success with IOP < or = 21 mmHg without antiglaucoma medications and 25 eyes (86%) achieved qualified success with IOP < or = 21 mmHg with or without medications at the last follow-up visit. Of the 25 eyes achieving qualified success, 24 (96%) had a reduction in the number of medications. There were 4 failures, defined as uncontrolled IOP requiring further filtering operation or oral drug treatment. Intraoperative complications included one accidental anterior chamber puncture and one iris plug intraoperatively. Postoperative complications included one choroidal effusion, three wound leaks requiring repair, and two punctate epithelial erosions. There was no shallowing of the anterior chamber, hyphema, hypotony, or infection encountered. CONCLUSIONS: Combined NPDS and phacoemulsification could be a safe and effective surgical option for the management of CACG with cataract.

Biomechanics of procedures used in adult flatfoot deformity.

A flatfoot deformity can occur secondary to fairly obvious causes, or more subtle and less definable entities. Complicating the situation further, it is likely that the cause of an acquired flatfoot deformity in an adult is multifactorial. This likelihood makes the definition, diagnosis, and appropriate treatment of this condition a daunting task. More research is needed to define further the biomechanics of the foot and to understand the significance of the forces that combine to create flatfoot deformity.

The effect of posterior tibial tendon dysfunction on hindfoot kinematics.

This biomechanical study investigated the functional role of the posterior tibial tendon (PTT) in acquired flatfoot mechanics. Acquired flatfoot deformity has been attributed to PTT dysfunction; however, the progression from acute dysfunction to end-stage deformity has not been fully demonstrated. Eight human cadaver lower leg and foot specimens were used in two phases of experimental testing. In Phase 1, intact (normal) specimens were loaded to simulate (a) heel strike, (b) stance, and (c) heel rise both with and without PTT function. Then, each specimen was subjected to a procedure designed to create a simulated flatfoot deformity. The resulting flattened feet were used in Phase 2 to examine the effect of restoring PTT function to a flatfoot model. During both phases of testing, the 3-D kinematic orientation of the hindfoot complex was recorded. Small but statistically significant changes in the angular orientation of the hindfoot complex were observed, during both Phase 1 and 2 testing, when comparing the effects of a functional and dysfunctional PTT. The greatest angular changes were recorded during heel rise. For the normal foot, the small changes observed in the orientation of the hindfoot complex following release of the PTT load suggest that the intact osteo-ligamentous structure of the hindfoot is initially able to maintain normal alignment following acute PTT dysfunction. Once the soft tissues have been weakened, as in our flatfoot model, the PTT had little effect in overcoming the soft tissue laxity to correct the position of the foot.

Tensile mechanics of the developing cervical spine.

This study examined the effect of spinal development (developmental age) on the tensile mechanics of the cervical spine. A total of 68 isolated functional spinal units were subjected to tensile loading to document their mechanical response (tensile stiffness and ultimate failure load). Cadaveric baboon specimens, ranging in age from 2 to 26 human-equivalent years, were used due to the limited availability of human tissues in the pediatric age range. Statistically significant correlation was found between developmental age and both tensile stiffness and ultimate failure load. Furthermore, differences in these properties were observed as a function of spinal level. In addition to providing age-related data for the developing spine, our findings suggest that reasonable scaling relationships exist between the adult and the child spine. These relationships provide a basis for scaling adult properties to the child, which may abet the development of pediatric neck injury tolerance values.

Glenohumeral kinematics and capsulo-ligamentous strain resulting from laxity exams.

OBJECTIVE: Identification and quantification of strain in shoulder capsular-ligamentous structures during clinical exams and validation of this testing on cadavers. METHODS: Mercury strain gauges were sutured in seven locations on shoulders from cadavers. An electromagnetic tracker quantified humeral head translations during laxity exams. Strain and humeral position were acquired during performance of Sulcus, Feagin, Apprehension, Load and Shift, Drawer, and Hawkins tests. RESULTS: Anterior humeral head translation in neutral position was primarily constrained by the coracohumeral ligament. With the arm abducted, anterior middle and inferior ligaments also became active. External rotation and abduction activated inferior and middle capsules. Posterior capsule constrained motion for posterior tests in neutral and abduction. Superior and inferior capsular ligaments were active during inferior tests in neutral position. With abduction, inferior ligaments provided primary translation constraint. CONCLUSION: Study of kinematics and strain evaluation on cadavers can yield useful information on mechanisms of glenohumeral instability. Relevance This study clarifies the contribution of specific structures of the shoulder to strain in the joint capsule. It also identifies which structures are challenged by provocative laxity exams commonly used by orthopaedic physicians.

Canal geometry changes associated with axial compressive cervical spine fracture.

STUDY DESIGN: A laboratory study using isolated ligamentous human cadaveric cervical spines to investigate canal occlusion during (transient) and after (steady-state) axial compressive fracture. OBJECTIVES: To determine whether differences exist between transient and postinjury canal occlusion under axial compressive loading, and to examine the effect of loading rate on canal occlusion. SUMMARY OF BACKGROUND DATA: Prior studies have shown no correlation between neurologic deficit and canal occlusion measurements made on radiographs and computed tomography scans. The authors hypothesized that postinjury radiographic assessment does not provide an appreciation for the transient occlusion that occurs during the traumatic fracture event, which may significantly affect the neurologic outcome. METHODS: Twelve human cervical spines were instrumented with a specially designed canal occlusion transducer, which dynamically monitored canal occlusion during axial compressive impact. Six specimens were subjected to a fast-loading rate (time to peak load, approximately 20 msec), and the other six were subjected to a slow-loading rate (time to peak load, approximately 250 msec). After impact, two different postinjury canal occlusion measurements were performed. RESULTS: Each of the six specimens subjected to the fast-loading rate incurred burst fractures, whereas the slow-loading rate produced six wedge-compression fractures. For the fast-rate group, the postinjury occlusion-measurements were significantly smaller than the transient occlusion. In contrast, transient occlusion was not found to be significantly different from postinjury occlusion in the slow-rate group. All of the comparisons between loading rate groups showed significant differences, with the fast-rate fractures producing larger amounts of canal occlusion in every category. CONCLUSIONS: The findings indicate that even if canal occlusion could be measured immediately after axial compressive trauma, the measurement would underestimate the maximal amount of transient canal occlusion. Therefore, postinjury measurement of canal occlusion may indicate a smaller degree of neurologic deficit than what might be expected if the transient occlusion could be measured.

Health education--Hong Kong's experience.

The HKSAR Department of Health is the Government's health adviser and agency to execute health care policies and statutory functions. It safeguards the health of the community through promotive, preventive, curative and rehabilitative services. The Department invests in health promotion activities and discharges its functions through three designated units, namely the Central Health Education Unit, Oral Health Education Unit and the Red Ribbon Centre for AIDS education, as well as through client contacts at primary and specialised health care centres. The Department is set to enhance its health information base, advocate for intersectoral collaboration and community participation in health, and engage in wider research and evaluation of health promotion interventions.

Subluxation of the talocalcaneal joint in adults who have symptomatic flatfoot.

BACKGROUND: When flatfoot is acquired during adulthood, the shape of the foot changes. In addition to a decreased arch, there may be valgus angulation of the hindfoot or abduction of the forefoot, or both. However, there is little objective information to provide a better understanding of the anatomical or morphological changes that occur in acquired adult flatfoot. We wondered if such an understanding of the three-dimensional anatomy might shed light on the pathway by which these changes occur. We designed this study to measure the three-dimensional position of the talocalcaneal joint in patients who have painful flatfoot. METHODS: Computed tomography scans of the feet of eight patients who had symptomatic flatfoot were used to construct a model of the talocalcaneal articulation. The scans were performed on a custom loading frame developed to simulate weight-bearing with the foot in a neutral position while a seventy-five-newton axial compressive load was applied. The digital data from the scans were used to make three-dimensional computer models of the articular surfaces of the talus and calcaneus of each foot. These models then were used to calculate the percentage of the articular surface that was in contact and, conversely, the percentage that was subluxated. Two surfaces were modeled for each bone; the posterior facet formed one surface, and the anterior and middle facets were combined to form the second surface. The data were compared, with use of Mann-Whitney nonparametric U analysis, with those derived from scans of the feet of four patients without a deformity of the hindfoot who served as controls. RESULTS: A mean (and standard deviation) of 68+/-9 percent of the posterior facet of the calcaneus was in contact with the talus in the patients who had flatfoot compared with 92+/-2 percent in the controls, and a mean of 51+/-23 percent of the anterior and middle facets of the calcaneus was in contact with the talus in the patients who had flatfoot compared with 95+/-6 percent in the controls. These differences were significant (p = 0.0066 for both). CONCLUSIONS: Marked subluxation of the talocalcaneal joint occurs in some patients who have symptomatic planoabductovalgus deformity.

Biomechanical analysis of the first metatarsocuneiform arthrodesis.

This investigation was designed to help define the unique loading characteristics of the first metatarsocuneiform arthrodesis procedure. Part I of this investigation employed nine fresh frozen, matched-pair cadaveric specimens. One specimen in each pair had the subchondral plate removed from the opposing joint surfaces, while the remaining specimen had only the articular cartilage removed. All specimens were stabilized in an identical manner utilizing two 3.5-mm cortical screws. Part II of the investigation also utilized nine fresh frozen, matched-pair cadaveric specimens. Only the articular cartilage was removed prior to placement of fixation. All specimens were stabilized with two crossing 3.5-mm cortical screws. Placement of a third screw was randomized between specimens of a matched pair. Specimens were loaded to failure in cantilever bending utilizing a materials tester. There was a statistically significant (p = .04) greater load to failure and bending moment in specimens with an intact subchondral plate. Values for construct stiffness were not found to be significantly different (p = .95) between specimens with and without a subchondral plate. Although the addition of a third screw increased the load to failure and bending moments, differences were not found to be statistically different (p = .11-.21) from two screws. Preserving the subchondral plate will enhance the stability of the first metatarsocuneiform arthrodesis. Two or three screws can be employed to shield the fusion site from loading; however, three screws were shown to be more effective than two.

Effect of variations in calcaneocuboid fusion technique on kinematics of the normal hindfoot.

Calcaneocuboid fusion with lengthening of the lateral column of the foot has been advocated as a method of treating flatfoot deformity. This study was designed to determine how the length of the lateral column chosen or the position of the foot selected when performing this fusion affect hindfoot kinematics in normal cadaver feet. An electromagnetic tracking system was used to monitor the positions of the talus, calcaneus, navicular, and cuboid while the intact cadaver feet were moved passively and then under reproducible loads. Calcaneocuboid fusion was then performed on these feet first with the feet in neutral position and the lateral column of normal length, then lengthened 10 mm or shortened 5 mm, and then with the lateral column lengthened 10 mm and the feet positioned in plantar flexion and eversion or dorsiflexion and inversion. Kinematic measurements were made at each stage using the same loads. Fusing the calcaneocuboid joint with lengthening or shortening the lateral column and the feet in neutral position did not affect hindfoot joint motion compared with intact. Changing the position of the foot for fusion, however, resulted in significant decreases in motion in the talocalcaneal and talonavicular joints. Tibiotalar joint motion was unaffected. This study, therefore, demonstrates that when fusing the calcaneocuboid joint, attention should be paid to maintaining a neutral position of the foot.

Alterations in talar morphology associated with adult flatfoot.

To gain a better understanding on the anatomy of the factors contributing to symptomatic flatfoot, we compared the shape of the talus in feet that were flat to that in control tali from feet with a normal arch. Computed tomographic (CT) scans were performed on 9 adult patients with 10 symptomatic flatfoot deformities. CT scans of 10 feet being evaluated for acute trauma not involving the talus were randomly selected as controls. Flatfoot tali tended to be of greater overall length than the control tali, and this difference was not statistically significant. Statistically significant differences were found when comparing ratios of talar length with talar width (P = 0.011), talar length with talar height (P = 0.001) (they were long relative to their height and width), and head length with head width (P = 0.001) for individual tali from the two groups. The tali from the flatfoot group were narrower in width and shorter in height when compared with overall length and had heads that were more elongated in the transverse plane than tali in feet with a normal appearance. CLINICAL CORRELATION: When performing surgical correction of a flatfoot in an adult, appearance of the foot rather than standard radiographic parameters should be used to judge the reduction. The altered shape of the bone may alter the standard radiographic parameters.

Damage to bicycle helmets involved with crashes.

The objective was to evaluate the relationship between helmet damage and head injuries in helmeted bicyclists in a sub-study of a large case-control study of bicycle injuries and helmet effectiveness. The setting consisted of seven hospital emergency departments in Seattle, WA. Hospitalized patients and medical examiners cases were included. The participants in the study were helmeted bicyclists who suffered a head injury or who damaged or hit their helmet in a crash. The Snell Memorial Foundation laboratory evaluated the helmets, blinded to crash circumstance and injury diagnosis. Damage was scored on a five-point scale (0 = none to 4 = destroyed). The damage location for each helmet was coded into regions (six longitudinal and three latitudinal) and mapped onto a three-dimensional CAD (computer-aided design) model of a helmet. The same procedure was also followed for injury location, which was mapped onto a three-dimensional ISO (International Organization for Standardization) headform for visualization of head-injury distribution. 785 helmeted subjects met the criteria for inclusion in the sub-study, and 527 helmets were purchased and evaluated (67%). 316 (60%) of the helmets had no or minimal damage, and 209 (39.7%) had significant damage (score 2, 3 or 4). Helmet types were 49.7% hard shell, 34.2% thin shell and 16.1% no shell. The risk of head and brain injury increased if the helmet was destroyed: OR = 5.3 (95% CI 2.9, 9.9) and OR = 11.2 (95% CI 3.5, 37.9), respectively. A high proportion of helmet impacts were along the front edge of the helmet, with a preponderance of head injuries in the same region. The large number of impacts to the front rim of the helmet, combined with the substantial number of riders with injuries to the forehead, indicate that some helmets, because of poor fit or wearing style, expose the forehead to injury. In addition, the data indicate that for a small proportion of injuries, the energy to the helmet may exceed design limits.