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Introduction: Whether under- or oversizing of the femoral component of cemented hip hemiarthroplasties impacts the risk of periprosthetic fractures (PPF) has only been examined experimentally. This study was carried out to add more knowledge about the risks of PPF in cemented polished tapered hemiarthroplasties. Methods: 20 patients with PPF following hip hemiarthroplasty with cemented Exeter V40 stems were compared to 50 controls who never suffered PPF having received the same type of Exeter hemiprosthesis for the same indication. The difference between stem size and post-hoc radiographic ideal templated size was investigated as a predictor of PPF. Results: Cases had a median size difference to post-hoc templating of –2, while controls had a median size difference of –1 ( p = 0.09). An ROC curve constructed to find an optimal cutoff point in size difference between cases and controls arrived at an area under curve of 63%, with –1.5 as the cutoff. Patients with size differences exceeding –1.5 had a statistically significant increased PPF risk (odds ratio = 3.8, 95% confidence interval, 1.1–13.3, p < 0.05). This group covered 55% of all cases. Conclusion: An implanted femoral component that is 2 or more sizes smaller than the template that is shown to be appropriate will increase the risk of PPF in Exeter hip hemiarthroplasties.

Prosthetic alignment is an essential process to rehabilitate patients with amputations. This study presents, for the first time, an invented device to read and record prosthesis alignment data. The digital device consists of seven main parts: the trigger, internal shaft, shell, sensor adjustment button, digital display, sliding shell, and tip. The alignment data were read and recorded by the user or a computer to replicate prosthesis adjustment for future use or examine the sequence of changes in alignment and its effect on the posture of the patient. Alignment data were recorded at the anterior/posterior and medial/lateral positions for five patients. Results show the high level of confidence to record alignment data and replicate adjustments. Therefore, the device helps patients readjust their prosthesis by themselves, or prosthetists to perform adjustment for patients and analyze the effects of malalignment.

Using a custom mobile application to evaluate the reliability and validity of the Component Timed-Up-and-Go test to assess prosthetic mobility in people with lower limb amputation.Cross-sectional design.National conference for people with limb loss.A total of 118 people with non-vascular cause of lower limb amputation participated. Subjects had a mean age of 48 (±13.7) years and were an average of 10 years post amputation. Of them, 54% ( n = 64) of subjects were male.None.The Component Timed-Up-and-Go was administered using a mobile iPad application, generating a total time to complete the test and five component times capturing each subtask (sit to stand transitions, linear gait, turning) of the standard timed-up-and-go test. The outcome underwent test-retest reliability using intraclass correlation coefficients (ICCs) and convergent validity analyses through correlation with self-report measures of balance and mobility.The Component Timed-Up-and-Go exhibited excellent test-retest reliability with ICCs ranging from .98 to .86 for total and component times. Evidence of discriminative validity resulted from significant differences in mean total times between people with transtibial (10.1 (SD: ±2.3)) and transfemoral (12.76 (SD: ±5.1) amputation, as well as significant differences in all five component times ( P .05). Convergent validity of the Component Timed-Up-and-Go was demonstrated through moderate correlations with the PLUS-M ( rThe Component Timed-Up-and-Go is a reliable and valid clinical tool for detailed assessment of prosthetic mobility in people with non-vascular lower limb amputation. The iPad application provided a means to easily record data, contributing to clinical utility.

Self-adjustment of hearing aid gain can provide valuable information about the gain preferences of individual listeners, but these preferences are not well understood. Listeners with mild-to-moderate hearing loss used self-adjustment to select amplification gain and compression parameters in real time on a portable touch screen device while listening in quiet and noisy backgrounds. Adjustments to gain prescribed by the National Acoustics Laboratories' non-linear fitting procedure (NAL-NL2) showed large between-subject variability. Known listener characteristics (age, gender, hearing thresholds, hearing aid experience, acceptable noise level, and external ear characteristics) and listener engagement with the self-adjustment software were examined as potential predictors of this variability. Neither listener characteristics nor time spent adjusting gain were robust predictors of gain change from NAL-NL2. Listeners with less than 2 years of hearing aid experience and who also had better hearing thresholds tended to select less gain, relative to NAL-NL2, than experienced hearing aid users who had poorer thresholds. Listener factors explained no more than 10% of the between-subject variance in deviation from NAL-NL2, suggesting that modifying prescriptive fitting formulae based on the factors examined here would be unlikely to result in amplification parameters that are similar to user-customized settings. Self-adjustment typically took less than 3 min, indicating that listeners could use comparable technology without a substantial time commitment.

PurposeTo compare patient-matched instrumentation (PMI) with conventional total knee arthroplasty (TKA) in terms of limb alignment and component position.MethodsNine men and 36 women (mean age, 69.5 years) who underwent PMI TKA were compared with 20 men and 25 women (mean age, 69.3 years) who underwent conventional TKA by the same team of surgeons with the same prosthesis and protocols in terms of limb alignment and component position using the Perth protocol computed tomography, as well as bone resection measurements, operating time, and the number of trays used.ResultsThe PMI and conventional TKA groups were comparable in terms of age, body mass index, tourniquet time, operating time, and the number of trays used. For limb alignment and component position, the 2 groups differed significantly in sagittal femoral component position (2.4° vs. 0.9°, p=0.0008) and the percentage of knees with femoral component internally rotated ≥1° with respect to the transepicondylar axis (20% vs. 55%, p=0.001). The difference was not significant in terms of limb alignment, coronal and rotational femoral component position, or coronal and sagittal tibial component position. Intra-operatively, all patient-matched cutting blocks demonstrated acceptable fit and stability. No instrument-related adverse events or complications were encountered. One (2.2%) femur and 6 (13.3%) tibiae were recut 2 mm for optimal ligament balancing. Two femoral components were upsized to the next size, and 2 tibial components were upsized and 2 downsized to the next size.ConclusionPMI was as accurate as conventional instrumentation in TKA. There was no significant difference in limb alignment or femoral and tibial component position in the coronal and sagittal planes between PMI and conventional TKA. PMI had a higher tendency to achieve correct femoral component rotation.

Objective Polyetheretherketone (PEEK) is a bioinert thermoplastic that has been investigated for its potential use in craniofacial reconstruction; however, its use in clinical practice is limited by a poor integration with adjacent bone upon implantation. To improve the bone–implant interface, two strategies have been employed: to modify its surface or to impregnate PEEK with bioactive materials. This study attempts to combine and improve upon the two approaches by modifying the internal structure into a trabecular network and to impregnate PEEK with mesenchymal stem cells. Furthermore, we compare the newly designed PEEK scaffolds' interactions with both bone-derived (BMSC) and adipose (ADSC) stem cells. Design Customized PEEK scaffolds were designed to incorporate a trabecular microstructure using a computer-aided design program and then printed via selective laser sintering (SLS), a 3D-printing process with exceptional accuracy. The scaffold structure was evaluated using microCT. Scanning electron microscopy (SEM) was used to evaluate scaffold morphology with and without mesenchymal stem cells (MSCs). Adipose and bone marrow mesenchymal cells were isolated from rats and cultured on scaffolds. Cell proliferation and differentiation were assessed using alamarBlue and alkaline phosphatase assays, respectively. Cell morphology after one week of co-culturing cells with PEEK scaffolds was evaluated using SEM. Results SLS 3D printing fabricated scaffolds with a porosity of 36.38% ± 6.66 and density of 1.309 g/cm2. Cell morphology resembled viable fibroblasts attaching to the surface and micropores of the scaffold. PEEK scaffolds maintained the viability of both ADSCs and BMSCs; however, ADSCs demonstrated higher osteodifferentiation than BMSCs ( p Conclusions This study demonstrates for the first time that SLS 3D printing can be used to fabricate customized porous PEEK scaffolds that maintain the viability of adipose and bone marrow-derived MSCs and induce the osteodifferentiation of the adipose-derived MSCs. The combination of 3D printed PEEK scaffolds with MSCs could overcome some of the limitations using PEEK biopolymers for load-bearing bone regeneration in craniofacial reconstruction.

Objective Our objective is to determine appropriate specifications for smaller tongue blade for Japanese pediatric patients with cleft palate (CP) and mandibular micrognathia. Patients We investigated 59 patients who underwent palatoplasty. Patients were divided into two groups: the micrognathia (MG) group consisted of 11 patients and the normognathia (NG) group consisted of 48 patients. Interventions The following five items were investigated retrospectively: (1) gender, (2) cleft type, (3) age at the time of surgery, (4) weight at the time of surgery, and (5) distance from the tongue blade base to the posterior pharyngeal wall (Dis). Result There was a significant difference (P < .01) in age at the time of surgery and in Dis between groups, but not in weight. The minimum values were 55 mm for the MG group. As for correlations between age and weight at the time of surgery, the P values for the MG and NG groups were .993 and .052, respectively. As for correlations between weight at the time of surgery and Dis, the P values for the MG and NG groups were .987 and .099, respectively. Conclusions It was difficult to predict Dis on the basis of the patient's age and weight measured preoperatively. The minimum Dis was 55 mm, equal to the length from the base to the tip of the Dingman Mouth Gag tongue blade currently in use, suggesting that a tongue blade of approximately 50 mm in length, shorter than the current minimum specifications, may be appropriate.

Background Lower extremity amputation (LEA) is a major surgical procedure with a high risk of significant morbidity and mortality. The objective of this study was to describe mortality and functionality outcomes following this procedure in a developing country. Methods This is a retrospective study of all patients undergoing LEA for non-traumatic etiology between 2007 and 2017. Medical records were used to retrieve demographics, comorbidities, and perioperative complications of identified patients. Patients were contacted to follow-up on their medical, postoperative care, and ambulatory status. Mortality and postoperative functionality rates were analyzed. Results The study included 78 patients. Median follow-up duration was 24 months. Hypertension (81%) and diabetes (79%) were the most common comorbidities. Mortality rates at 30 days, 1, and 5 years were 10.3, 29.2, and 65.5%, respectively. Mortality was significantly associated with age > 70 at amputation ( p = 0.042), hypertension ( p = 0.003), chronic kidney disease ( p = 0.031), and perioperative sepsis ( p = 0.01). Only 1.6% of patients were discharged into a specialized care center, and only 27% of patients were ambulatory postoperatively, although 90.5% were fitted with a prosthesis. Conclusions Survival following major amputation in a developing country is currently comparable to more developed regions of the world. Major discrepancy seems to exist in ambulatory status following the procedure. Discharge placement policies should be properly set, and rehabilitation centers funding should be increased. Awareness may also be warranted to educate patients and families about the value and positive impact of rehabilitation centers.

Self-fitting hearing aids (SFHAs)-devices that enable self-directed threshold measurements leading to a prescribed hearing aid (HA) setting, and fine-tuning, without the need for professional support-are now commercially available. This study examined outcomes obtained with one commercial SFHA, the Companion (SoundWorld Solutions), when support was available from a clinical assistant during self-fitting. Participants consisted of 27 experienced and 25 new HA users who completed the self-fitting process, resulting in 38 user-driven and 14 clinician-driven fittings. Following 12 weeks' experience with the SFHAs in the field, outcomes measured included the following: coupler gain and output, HA handling and management skills, speech recognition in noise, and self-reported benefit and satisfaction. In addition, the conventionally fitted HAs of 22 of the experienced participants who had user-driven fittings were evaluated. Irrespective of HA experience, the type of fitting (user- or clinician-driven) had no significant effect on coupler gain, speech recognition scores, or self-reported benefit and satisfaction. Users selected significantly higher low-frequency gain in the SFHAs when compared with the conventionally fitted HAs. The conventionally fitted HAs were rated significantly higher for benefit and satisfaction on some subscales due to negative issues with the physical design and implementation of the SFHAs, rather than who drove the fitting process. Poorer cognitive function was associated with poorer handling and management of the SFHAs. Findings suggest that with the right design and support, SFHAs may be a viable option to improve the accessibility of hearing health care.

Modern hearing instruments contain logging technology to record data, such as the acoustic environments in which the device is being used and how the signal processing is consequently operating. Combined with patient data, such as the audiogram, this information gives a more comprehensive picture of the user and their relationship with the aid. Here, a relatively large, anonymized dataset ( 4300,000 devices, 4150,000 wearers) from a hearing-aid manufacturer was data mined for connections between subsets of the logged varieties of data. Apart from replicating links that have previously been reported in labor-intensive studies, a link between device style (in-the-ear/behind-the-ear) and the sound levels of encountered environments was demonstrated, suggesting that some device types are more successful from a lifestyle perspective. Furthermore, the data also suggested links between the audiogram and the sound environments in which the aid was operated. Modeling the expected link between the environment and the microphone directionality settings revealed patterns of either abnormal fitting or where the aid was not operating correctly—factors that may indicate a failed fitting.Given the necessarily redacted nature of the dataset, the reported findings represent a proof-of-concept of the use of relatively large-scale data mining to guide and assess hearing-aid fitting procedures for possible benefits to the clinician, manufacturer, and patient.

This research was conducted to evaluate the efficacy of an online speech perception test (SPT) for the measurement of hearing and hearing aid fitting in comparison with conventional methods. Phase 1 was performed with 88 people to evaluate the SPT for the detection of significant hearing loss. The SPT had high sensitivity (94%) and high selectivity (98%). In Phase 2, phonetic stimulus–response matrices derived from the SPT results for 408 people were used to calculate “Infograms™.” At every frequency, there was a highly significant correlation ( p

Background: Contemporary total ankle prostheses embody design changes intended to address weaknesses in first-generation implants. Due to these changes, outcomes of the newer designs are of particular interest. We have previously published self-reported patient outcomes for the STAR (Scandinavian Total Ankle Replacement) prosthesis. The present study documents radiographic outcome measurements for the STAR prosthesis at intermediate to long-term follow-up. Methods: Of 89 consecutive ankle replacements performed between July 1998 and April 2007, 79 had a minimum follow-up of 2 years and were followed prospectively. Serial radiographs were measured by 2 of the authors, including varus, valgus, alpha, beta, and gamma angles, as well as point contact ratio. Inter- and intrarater reliability was calculated and reported. A “severe” subgroup of patients with preoperative coronal plane deformity exceeding 10 degrees was assessed separately. Preoperative and immediate postoperative measurements were compared and maintenance of correction evaluated on subsequent radiographs. Heterotopic ossification and pericomponent lucency were documented and followed, and subsequent procedures were recorded to follow survivorship. The mean follow-up was 8.0 years. Results: Of the 79 ankles, 25 underwent a secondary surgery (31.6%). Coronal correction averaged 5.1 degrees ( P < .001), and this was maintained to final follow-up. The severe subgroup (n = 21), with a mean preoperative coronal angulation of 16.1 degrees, was corrected to 4.6 degrees at final follow-up ( P < .001). The severe subgroup had a higher secondary surgery rate at 33.3%, with metallic component revision or failure occurring in 3 cases (14.3%) compared to 8 (10.1%) in the entire cohort. The heterotopic ossification rate was 100%, slightly higher than prior reports. Conclusions: STAR prosthesis survivorship was similar to that documented in prior studies of second-generation implants in European patient cohorts. Statistically significant correction in coronal alignment was achieved immediately after surgery and maintained until a final mean follow-up of 8 years, even in patients with preoperative deformity greater than 10 degrees. Level of Evidence: Level III, retrospective cohort study.

Palatal and pharyngeal surgeries often require wide visibility and access. Various mouth gags and retractors have been devised and many modifications suggested to optimize these surgeries. The Dingman mouth gag, one of the commonly used retractors, offers a lot of advantages in terms of good mouth opening, tongue retraction, self-retaining cheek retractors, and anchorage for sutures, but it has a main limitation in that it allows only limited visibility of the anterior palate and alveolus. Hence, a modification of the Dingman mouth gag is presented for better visibility of and accessibility to the anterior palate.

Background: Ankle fusions fixed with anterior plates use fluoroscopic guidance to direct screws toward the subtalar joint. Special imaging views that visualize the subtalar joint are difficult to use and can be unreliable. This study evaluated whether a single lateral ankle view would provide adequate information to judge whether a screw penetrated the subtalar joint and identified strategies that would improve this technique. Methods: In 5 cadaveric ankles fixed with anterior plates, talar screws were placed up to the subtalar joint without penetration using lateral fluoroscopy to guide screw length. After dissection, the true distance from the screw tip to subchondral surface was measured. In addition, 4 readers measured the perceived distance from screw tip to subchondral surface using direct lateral, 10 degrees cephalad tilt lateral, and 10 degrees caudal tilt lateral fluoroscopic images on 2 separate occasions. Results: Nineteen (63%) of 30 screws penetrated the subchondral bone, and screw length determined using fluoroscopy was significantly longer than screw length measured directly (29.4 ± 5.5 mm vs 27.3 ± 8.5 mm, P = .014). Measurement of screw tip to bone distance demonstrated a high level of within-reader (kappa = .871, P < .001) and between-reader agreement (kappa = .807, P < .001), but poor specificity of determining screw penetration (0.50, χ2 = 22.1, P < .001) and poor correlation between radiographically measured and actual distances between screw tip and bone margin ( r = .35, P < .001). Tilting the c-arm 10 degrees cephalad and directing screws toward the posterior facet improved the ability to detect screw penetration and directing screws toward the middle facet diminished it ( P < .05). A safe zone of screw placement was defined by region. Conclusion: Use of a lateral fluoroscopic image to guide talar screw placement may lead to an unacceptably high rate of subtalar joint penetration. Clinical Relevance: Understanding the limitations of lateral fluoroscopy when using anterior ankle fusion plates may minimize screw penetration into the subtalar joint and diminish development of subtalar arthropathy.

Intramedullary nailing is the standard fixation method for displaced diaphyseal fractures of the tibia. An optimal nail design should both facilitate insertion and anatomically fit the bone geometry at its final position in order to reduce the risk of stress fractures and malalignments. Due to the nonexistence of suitable commercial software, we developed a software tool for the automated fit assessment of nail designs. Furthermore, we demonstrated that an optimised nail, which fits better at the final position, is also easier to insert. Three-dimensional models of two nail designs and 20 tibiae were used. The fitting was quantified in terms of surface area, maximum distance, sum of surface areas and sum of maximum distances by which the nail was protruding into the cortex. The software was programmed to insert the nail into the bone model and to quantify the fit at defined increment levels. On average, the misfit during the insertion in terms of the four fitting parameters was smaller for the Expert Tibial Nail Proximal bend (476.3 mm2, 1.5 mm, 2029.8 mm2, 6.5 mm) than the Expert Tibial Nail (736.7 mm2, 2.2 mm, 2491.4 mm2, 8.0 mm). The differences were statistically significant ( p ≤ 0.05). The software could be used by nail implant manufacturers for the purpose of implant design validation.

Two amplification features were examined using auditory tasks that varied in stimulus familiarity. It was expected that the benefits of certain amplification features would increase as the familiarity with the stimuli decreased. A total of 20 children and 15 adults with normal hearing as well as 21 children and 17 adults with mild to severe hearing loss participated. Three models of ear-level devices were selected based on the quality of the high-frequency amplification or the digital noise reduction (DNR) they provided. The devices were fitted to each participant and used during testing only. Participants completed three tasks: (a) word recognition, (b) repetition and lexical decision of real and nonsense words, and (c) novel word learning. Performance improved significantly with amplification for both the children and the adults with hearing loss. Performance improved further with wideband amplification for the children more than for the adults. In steady-state noise and multitalker babble, performance decreased for both groups with little to no benefit from amplification or from the use of DNR. When compared with the listeners with normal hearing, significantly poorer performance was observed for both the children and adults with hearing loss on all tasks with few exceptions. Finally, analysis of across-task performance confirmed the hypothesis that benefit increased as the familiarity of the stimuli decreased for wideband amplification but not for DNR. However, users who prefer DNR for listening comfort are not likely to jeopardize their ability to detect and learn new information when using this feature.

In the past decades, more than 40 mitral valve annuloplasty rings of various shapes and consistency were marketed for mitral regurgitation (MR), although the effect of ring type on clinical outcome remains unclear. Our objective was to review the literature and apply a simplification method to make rings of different shapes and rigidity more comparable. We studied relevant literature from MEDLINE and EMBASE databases related to clinical studies as well as animal and finite element models. Annuloplasty rings were clustered into 3 groups as follows: rigid (R), flexible (F), and semirigid (S). Only clinical articles regarding degenerative (DEG) or ischemic/dilated cardiomyopathy (ICM) MR were included and stratified into these groups. A total of 37 rings were clustered into R, F, and S subgroups. Clinical studies with a mean follow-up of less than 1 year and a reported mean etiology of valve incompetence of less than 60% were excluded from the analysis. Forty-one publications were included. Preimplant and postimplant end points were New York Heart Association class, left ventricular ejection fraction (LVEF), left ventricular end-systolic dimension (LVESD), and left ventricular end-diastolic dimension (LVEDD). Statistical analysis included paired-samples t test and analysis of variance with post hoc Bonferroni correction. P < 0.05 indicated statistical difference. Mean ± SD follow-up was 38.6 ± 27 and 29.7 ± 13.2 months for DEG and ICM, respectively. In DEG, LVEF remained unchanged, and LVESD decreased in all subgroups. In our analysis, LVEDD decreased only in F and R, and S did not change; however, the 4 individual studies showed a significant decline. In ICM, New York Heart Association class improved in all subgroups, and LVEF increased. Moreover, LVESD and LVEDD decreased only in F and S; R was underpowered (1 study). No statistical difference among R, F, and S in either ICM or DEG could be detected for all end points. Overall, owing to underpowered data sets derived from limited available publications, major statistical differences in clinical outcome between ring types could not be substantiated. Essential end points such as recurrent MR and survival were incomparable. In conclusion, ring morphology and consistency do not seem to play a major clinical role in mitral valve repair based on the present literature. Hence, until demonstrated otherwise, surgeons may choose their ring upon their judgment, tailored to specific patient needs.

Purpose.To assess the accuracy of templating in total hip arthroplasty (THA).Methods.Anteroposterior pelvic radiographs of 20 men and 33 women aged 17 to 80 (mean, 60) years who underwent uncemented THA of the right (n=24) and left (n=29) sides using a single prosthesis were reviewed. A 30-mm–diameter scaling ball was placed between the patient's legs for calculating the magnification factor (MF) of the radiographs. The planned THA was templated using computer software. The positioning of the scaling ball was measured. The preoperative MF was calculated as the size of the ball on radiograph divided by the true size of the ball times 100. The true MF was calculated as the size of the cup on radiograph divided by the true size of the cup times 100. The accuracy of the preoperative MF was calculated as the preoperative MF divided by the true MF times 100.Results.The cup size and stem size were predicted correctly (within one size error) in 87% and 92% of the patients, respectively; no template size was greater than 3 size errors. The overall mean pre-and post-operative MFs differed significantly (122% vs. 127%, p±0.001), as did the mean postoperative MFs between males and females (126% vs. 128%, p=0.006). Assuming the MF was constant, and the postoperative measurement was the most accurate, the mean accuracy of preoperative MF was 96% (range, 89.6–99.9%), whereas the relative mean height of the scaling ball was 30 (range, 1–90) mm away from the correct height. The accuracy of the preoperative MF did not correlate with body mass index, the scaling ball position, and the accuracy of cup and stem templates.Conclusion.If the MF of 127% is constant across different patients, using a MF of 127% is more accurate than using the scaling ball technique.

Objective: This study aimed to review current knowledge regarding implantation of the Vibrant Soundbridge floating mass transducer (FMT) at the round window (round window vibroplasty) as well as to form a consensus on steps for a reliable, stable surgical procedure. Data Sources: Review of the literature and experimental observations by the authors. Conclusion: Round window (RW) vibroplasty has been established as a reliable procedure that produces good and stable results for patients with conductive or mixed hearing loss. The experience gained over the past few years of the authors’ more than 200 implantations has led to consensus on several key points: (1) a wide and bloodless access to the middle ear with facial nerve monitoring, (2) the careful and correct identification and exposure of the round window membrane, (3) a good setup for efficient energy transition of the FMT, namely, perpendicular placement of the FMT with no contact to bone and the placement of cartilage behind the FMT to create a preloaded “spring” function, and (4) 4 points of FMT fixation: a rim of the round window bony overhang left intact both anterior and posterior to the FMT, conductor link stabilization, and cartilage behind the FMT. In addition, the FMT should be covered with soft tissue.

Purpose To show applications of different types of gas-permeable contact lenses in patients with keratoconus and to compare visual acuity (VA) results. Methods A total of 229 eyes of 133 patients who used different types of rigid gas-permeable contact lenses between April 2003 and April 2010 at the Cornea and Contact Lens Unit of Eye Clinic 2 of the Ministry of Health, Ulucanlar Eye Training and Research Hospital, were included. Visual acuity of patients was classified as uncorrected and corrected with eyeglasses and corrected with contact lenses. The patients were compared in terms of VA, daily contact lens wear time, and complications. Results A total of 70 out of 133 (52.6%) patients in our study were male, and 63 (47.4%) were female. The mean age was 25.9 ± 7.03 years (12-45). As for the classification of the 229 eyes included in the study, 136 of 229 (59.4%) eyes had moderate keratoconus, 88 (38.4%) had advanced keratoconus, and 5 (2.2%) had severe keratoconus. Following the contact lens application, the VA in all patients increased when compared to uncorrected and corrected with eyeglasses groups and the difference was statistically significant (p0.5) in terms of increase in VA. When patients were evaluated in terms of contact lens wear times, it was observed that Boston Equalens II was preferred by patients wearing lenses 4–8 hours/day. For patients wearing lenses more than 8 hours a day, Rose K lens was used the most. No serious complication was observed in any of the patients that would lead them to stop wearing contact lenses during the follow-up period. There was also no need for keratoplasty in any patient during the follow-up period. Conclusions We detected an increase in VA in patients with rigid contact lenses. In addition, some contact lenses were better tolerated by patients and were used for a longer time during the day.

A major decision at the time of hearing aid fitting and dispensing is the amount of amplification to provide listeners (both adult and pediatric populations) for the appropriate compensation of sensorineural hearing impairment across a range of frequencies (e.g., 160–10000 Hz) and input levels (e.g., 50–75 dB sound pressure level). This article describes modern prescription theory for hearing aids within the context of a risk versus return trade-off and efficient frontier analyses. The expected return of amplification recommendations (i.e., generic prescriptions such as National Acoustic Laboratories—Non-Linear 2, NAL-NL2, and Desired Sensation Level Multiple Input/Output, DSL m[i/o]) for the Speech Intelligibility Index (SII) and high-frequency audibility were traded against a potential risk (i.e., loudness). The modeled performance of each prescription was compared one with another and with the efficient frontier of normal hearing sensitivity (i.e., a reference point for the most return with the least risk). For the pediatric population, NAL-NL2 was more efficient for SII, while DSL m[i/o] was more efficient for high-frequency audibility. For the adult population, NAL-NL2 was more efficient for SII, while the two prescriptions were similar with regard to high-frequency audibility. In terms of absolute return (i.e., not considering the risk of loudness), however, DSL m[i/o] prescribed more outright high-frequency audibility than NAL-NL2 for either aged population, particularly, as hearing loss increased. Given the principles and demonstrated accuracy of desensitization (reduced utility of audibility with increasing hearing loss) observed at the group level, additional high-frequency audibility beyond that of NAL-NL2 is not expected to make further contributions to speech intelligibility (recognition) for the average listener.

The objectives of the present study were to determine ( 1 ) whether differences in the radiographic appearance of the of the proximal femoral canal exist on corresponding AP pelvis and AP hip radiographs, and ( 2 ) whether radiographic assessment of canal shape is accurate with reference to computed tomography (CT). In a retrospective study, corresponding radiographs and CT scans of 100 consecutive patients with primary hip OA were evaluated. Active shape modelling (ASM) was performed to assess the variation in proximal femoral canal shape and to identify differences between AP hip and AP pelvis views. Differences in the medial cortical flare between radiographs and CT were quantified using least squares curve fitting. ASM identified significant differences in the assessment of canal shape on corresponding AP hip and AP pelvis views. Curve fitting demonstrated a good agreement between AP hip radiographs and CT. Agreement between AP pelvis radiographs and CT was less good. In contrast to AP pelvis radiographs, AP hip radiographs allow a more accurate and reliable assessment of proximal femoral canal shape in the frontal plane in primary hip OA. Our findings may improve stem fit in total hip arthroplasty without the routine use of CT.

Cochlear implant systems that combine electric and acoustic stimulation in the same ear are now commercially available and the number of patients using these devices is steadily increasing. In particular, electric-acoustic stimulation is an option for patients with severe, high frequency sensorineural hearing impairment. There have been a range of approaches to combining electric stimulation and acoustic hearing in the same ear. To develop a better understanding of fitting practices for devices that combine electric and acoustic stimulation, we conducted a systematic review addressing three clinical questions: what is the range of acoustic hearing in the implanted ear that can be effectively preserved for an electric-acoustic fitting?; what benefits are provided by combining acoustic stimulation with electric stimulation?; and what clinical fitting practices have been developed for devices that combine electric and acoustic stimulation? A search of the literature was conducted and 27 articles that met the strict evaluation criteria adopted for the review were identified for detailed analysis. The range of auditory thresholds in the implanted ear that can be successfully used for an electric-acoustic application is quite broad. The effectiveness of combined electric and acoustic stimulation as compared with electric stimulation alone was consistently demonstrated, highlighting the potential value of preservation and utilization of low frequency hearing in the implanted ear. However, clinical procedures for best fitting of electric-acoustic devices were varied. This clearly identified a need for further investigation of fitting procedures aimed at maximizing outcomes for recipients of electric-acoustic devices.

Intracranial vertebral artery dissection can be associated with subarachnoid hemorrhage (SAH) and pseudoaneurysm formation. Dissecting aneurysms have a high risk of rebleeding in the acute phase. To our knowledge, the management of an acute vertebrobasilar junction dissecting aneurysm associated with a basilar non-fusion has not been previously reported. We report here a case of SAH due to rupture of a dissecting aneurysm involving the vertebrobasilar junction and extending to involve the right limb and proximal junction of a non-fused basilar artery, managed by insertion of a flow-diverting stent with excellent clinical outcome and long-term patency of the flow diverter.

Knee joint implants developed by western companies have been imported to Korea and used for Korean patients. However, many clinical problems occur in knee joints of Korean patients after total knee joint replacement owing to the geometric mismatch between the western implants and Korean knee joint structures. To solve these problems, a method to determine the representative dimension parameter values of Korean knee joints is introduced to aid in the design of knee joint implants appropriate for Korean patients. Measurements of the dimension parameters of 88 male Korean knee joint subjects were carried out. The distribution of the subjects versus each measured parameter value was investigated. The measured dimension parameter values of each parameter were grouped by suitable intervals called the “size group,” and average values of the size groups were calculated. The knee joint subjects were grouped as the “patient group” based on “size group numbers” of each parameter. From the iterative calculations to decrease the errors between the average dimension parameter values of each “patient group” and the dimension parameter values of the subjects, the average dimension parameter values that give less than the error criterion were determined to be the representative dimension parameter values for designing knee joint implants for Korean patients.

Purpose.To report the long-term results of total hip arthroplasty (THA) using small size Exeter femoral stems.Methods.Eight men and 34 women aged 60 to 83 (mean, 70) years underwent 45 THAs using the Exeter small stem with offsets of 30 mm (n=3), 33 mm (n=15), and 35.5 mm (n=27). The Harris hip score was assessed pre- and post-operatively. Stem alignment and axial subsidence of the stem were measured. Radiolucent lines around the femur were recorded at 14 Gruen zones. Completeness and thickness of the cement mantle and cement fractures were also noted. Ectopic ossification, if present, was graded. Stem loosening was based on the Olsson definitions.Results.The mean follow-up was 9 (range, 5–12) years. The mean Harris hip score improved from 37 (range, 13–61) to 80 (range, 47–96) [pConclusion.The results of Exeter small stems for patients with small femurs are good.

To assess the effect of intensive statins therapy on the outcome of small-diameter vascular prosthesis, we investigated whether atorvastatin treatment (30 mg/d) could accelerate the re-endothelialization process and improve the patency rate in a canine infrarenal abdominal aorta-expanded polytetrafluoroethylene (ePTFE) bypass model. Furthermore, we also evaluated the effect of atorvastatin on the migratory and adherent capacity of circulating endothelial progenitor cells (EPCs) in vitro. Improved patency was confirmed by Doppler sonography and arteriography. Histological and scanning electron microscopy illustrated enhanced re-endothelialization process. Treatment with atorvastatin enhanced the circulating pool of EPCs with fortified migratory and adherent capacity. Reverse transcriptase—polymerase chain reaction (RT-PCR) analysis showed that atorvastatin treatment increased endothelial nitric oxide synthase (eNOS) and kinase insert domain receptor (KDR) messenger RNA (mRNA) expression in cultured EPCs and neointima. In conclusion, intensive statin therapy could be considered a favorable option to improve small-diameter vascular graft patency.

Purpose. To evaluate the discrepancy between the anatomical axis of the distal femur of Japanese patients and the stem position of 5 types of femoral components. Methods. Lateral radiographs of 12 men and 88 women aged 31 to 83 (mean, 59) years with rheumatoid arthritis were evaluated. The discrepancy between the anatomical axis of the distal femur and the stem position of 5 types of femoral components (Nexgen LCCK, Press-Fit Condylar, Scorpio, Total Stabilizer, and Rotating Hinge) was determined by superimposing the template of each model over each lateral radiograph. Results. The anatomical axis varied widely among our patients, as did the stem position of the 5 femoral components. Stems of all 5 femoral components tended to be more posterior than the anatomical axis. The discrepancy was smallest in the Nexgen LCCK, followed by the Press-Fit Condylar components. It was >3 mm in the other 3 models. In 35% of the patients, none of the prosthesis could be placed in an appropriate position. Smaller-size prostheses appear necessary for the Japanese. Conclusion. The stem position should be an important factor guiding selection of the appropriate model. The currently available femoral components may not be appropriate for the Japanese. Prostheses with appropriately positioned stems for Japanese patients with rheumatoid arthritis should be developed.

There is lack of a systematic approach concerning how to select an adequate hearing aid and how to evaluate its efficacy with respect to the personal needs of rehabilitation. The goal of this study was to examine the applicability and added value of two widely used self-reporting questionnaires in relation to the evaluation of hearing aid fitting. We analyzed responses, pre- and postfitting, from 1,319 subjects who completed the Client Oriented Scale of Improvement (COSI) and a slightly adapted version of the Amsterdam Inventory for Auditory Disability and Handicap (in Dutch: AVAB). Most COSI responses were at or near the maximum possible score. Results show a close relation between COSI’s degree of change and final ability (Spearman’s rho = 0.71). Both AVAB and COSI showed a significant effect of hearing aid experience, but—in contrast to AVAB—COSI did not show a significant effect of the degree of hearing loss. In addition, a Friedman test showed significant differences between six dimensions of auditory functioning for both AVAB and COSI, although post hoc analysis revealed that for COSI, the dimension speech in quiet explained most variation between dimensions. In conclusion, the effects of hearing loss were more salient in AVAB, while both AVAB and COSI showed differences regarding hearing aid experience. Combining the advantages of both methods results in a detailed evaluation of hearing aid rehabilitation. Our results therefore suggest that both methods should be used in a complementary manner, rather than separately.

The method of paired comparisons was introduced into the hearing aid literature nearly 50 years ago. Over time, studies have found paired comparisons to be sensitive, valid, and reliable in determining either the perceptual difference or relative ranking among hearing aids and electroacoustic characteristics. With the increasing number of adjustable electroacoustic parameters in today’s digital hearing aids—and the lack of procedural guidelines necessary to fit many of them—the method of paired comparisons provides the clinician with the ability to compare different devices, electroacoustic characteristics, memory settings, or combinations of these variables under the listener’s everyday listening conditions. Furthermore, this procedure provides the clinician with the ability to individualize the prescriptive approach—which is predicated mainly on hearing threshold data and listening in quiet—so that a combination of parameters can be set to optimize the user’s listening needs in a given environment. In this article, the authors present an overview of the theoretical principle supporting this procedure, the various paired-comparison strategies and associated approaches, the advantages of this method, and recommended procedures for implementing the method of paired comparisons in the fitting of today’s sophisticated hearing aids.

Seventy-seven patients implanted with unilateral resurfacing prosthesis were recruited from four centres. Serial whole blood samples were collected and ion levels were analysed. In most cases, the ion levels stabilized by 3 months. The 24 month median ion levels were 1.49ug/l for chromium and cobalt. In approximately 50% of patients the increase in chromium and cobalt level was less than 1ug/l. There were 6 patients with abnormally high metal ion levels. Of these 4 were significant outliers, had high ion levels that became apparent between 12 and 24 months after implantation, and had a high cup abduction angle. Not all patients with high cup abduction angles demonstrated high levels. There were differences in ion levels between the four centres that correlated with variation in acetabular component placement. Variability in ion levels was seen with the same prosthesis, underscoring the importance of surgical technique, longitudinal analysis, and multi-centre trials.

When hearing aid gain is prescribed by software, gain is calculated based on the average acoustics for the age of patient, gender, mold type, and so on. The acoustics of the individual's ear often vary from the average values, so there will be a mismatch between the prescribed gain and the real-ear gain. Real-ear measurement can be used to verify the gain and adjust it to meet targets, but the quality of the match will be limited by the number of channels and the flexibility of the hearing aid. A potential way to improve this process is to generate a filter that compensates for variations in real-ear insertion gain due to individual ear acoustics. Such a filter could be included in the processing path of a digital hearing aid. This article describes how such a filter can be generated using the windowing method, and the principle is demonstrated in a real ear. The approach requires communication between the real-ear measurement and hearing aid programming software. A finite impulse response filter with group delay just over 2 ms matched insertion gain to target values within the acceptable tolerance defined by British Society of Audiology guidelines.

Changes in the sensory environment modify our sensory experience and may result in experience-related or learning-induced reorganization within the central nervous system. Hearing aids change the sensory environment by stimulating a deprived auditory system; therefore, they may be capable of inducing changes within the central auditory system. Examples of studies that have shown hearing aid induced perceptual and/or physiological changes in the adult human auditory system are discussed. Evidence in the perceptual domain is provided by studies that have investigated (a) speech perception, (b) intensity discrimination, and (c) loudness perception. Evidence in the physiological domain is provided by studies that have investigated acoustic reflex thresholds and event-related potentials. Despite the controversy in the literature concerning the rate, extent, and clinical significance of the acclimatization effect, there is irrefutable evidence that the deprived auditory system of some listeners can be modified with hearing aid experience.

The effect of the contrast agent iohexol on reference vessel size in patients with proximal left anterior descending disease is unknown. Quantitative coronary angiography and intravascular ultrasound were performed in 15 patients with atherosclerotic disease of the proximal left anterior descending. Mean proximal reference vessel diameter was 2.95 ± 0.59 mm with quantitative coronary angiography and 4.65 ± 0.66 mm with intravascular ultrasound ( P < .05). Intracoronary injection of iohexol resulted in a significant decrease in intravascular ultrasound-measured proximal reference vessel diameter from 4.65 ± 0.66 mm to 4.47 ± 0.68 mm ( P = .002). Vasoconstrictive response to iohexol in the proximal reference vessel ranged from −0.04 mm to 0.5 mm with a mean of 0.18 ± 0.16 mm. This study shows that iohexol can cause significant vasoconstriction of the proximal reference vessel in patients with severe disease involving the proximal left anterior descending.

Previous studies of CAD/CAM-produced sacrificial patterns for removable partial denture frameworks have been documented but to date, no such restorations have been test-fitted to a patient. This paper provides details of the first trial fitting to a patient of an RPD framework, the sacrificial pattern of which was produced by CAD/CAM and RP technologies. A cast of the patient was scanned and the normal procedures of dental surveying and pattern build were undertaken with reference to the scanned model using computer-aided design. A sacrificial pattern of the design was produced by rapid prototyping technology. After spruing the pattern, investment-casting and finishing techniques were carried out according to conventional principles. The framework was successfully trial-fitted to the patient and clinically judged to be acceptable for the next stage of denture fabrication, that of adding acrylic bases and artificial teeth.

The Ilizarov fixator consists of tensioned wires that attach bone segments to a modular frame. The aim of this study was to establish the accuracy and precision of the wire-tensioning device supplied with the Ilizarov external fixation system. The device was used to tension a wire in direct opposition to a calibrated load cell. Five subjects tested three devices, at each of their four tension settings, in two separate sessions. Subjects could not see the true tension during the test. There were significant differences between the results for different subjects ( p

Adaptive dynamic range optimization (ADRO) is an amplification strategy that uses digital signal processing techniques to improve the audibility, comfort, and intelligibility of sounds for people who use cochlear implants and/or hearing aids. The strategy uses statistical analysis to select the most information-rich section of the input dynamic range in multiple-frequency channels. Fuzzy logic rules control the gain in each frequency channel so that the selected section of the dynamic range is presented at an audible and comfortable level. The ADRO processing thus adaptively optimizes the dynamic range of the signal in multiple-frequency channels. Clinical studies show that ADRO can be fitted easily to all degrees of hearing loss for hearing aids and cochlear implants in a direct and intuitive manner, taking the preferences of the listener into account. The result is high acceptance by new and experienced hearing aid users and strong preferences for ADRO compared with alternative amplification strategies. The ADRO processing is particularly well suited to bimodal and hybrid stimulation which combine electric and acoustic stimulation in opposite ears or in the same ear, respectively.

The Desired Sensation Level (DSL) Method was originally developed in the early 1980s to provide clinicians with a systematic, science-based approach to pediatric hearing instrument fitting that ensures audibility of amplified speech by accounting for factors that are uniquely associated with the provision of amplification to infants and young children who have hearing loss. This review identifies and describes several of the primary factors that have been considered in the development of the DSL Method. Specifically, the issues discussed relate to: (1) the definition and measurement of relevant acoustic, electroacoustic and audiometric variables; (2) how the external ear acoustics of infants and young children are accounted for in the DSL Method for both audiometric assessment and in the fitting of amplification; and (3) how the DSL Method has evolved concurrently with developments in hearing instrument and electroacoustic measurement technologies. Finally, current issues in the field are identified that have motivated the development of version 5.0 of the DSL Method for hearing instrument fitting.

We conducted a study to determine whether application sharing and desktop videoconferencing using the Internet constituted a viable method for remotely configuring a microprocessor-controlled lower-extremity prosthesis. A DSL broadband connection (operated at 256 kbit/s) was used to connect two prosthetic care facilities over the public Internet. PC-based videoconferencing was used with application sharing for the remote configuration of the prosthesis and to view information on the load and angle of the prosthetic knee. Fifteen people with trans-femoral amputations had the settings for their prosthesis scrambled before a specialist at another site remotely configured the device. There were no significant differences between the original and online settings. Clinicians at both sites considered that 14 out of 15 sessions were successful (one trial involved technical problems with the knee unit that were unrelated to the telemedicine trial). The clients rated their satisfaction with the technique as excellent (47%), above average (33%) or average (20%). The present study shows that a combination of desktop videoconferencing and T.120 application sharing can be used for the remote configuration of assistive devices.

Reciprocal walking orthoses are routinely used by thoracic lesion patients for ambulation using crutches. A primary reason for their prescription is to provide therapeutic benefit and improved independence. To achieve this, maximum efficiency of walking and acceptance of the device is necessary to promote long-term compliance. Lateral rigidity in the orthosis influences walking efficiency, but the structural properties of conventional techniques for producing a sufficiently rigid body brace makes them unattractive. Currently patients and clinicians are forced to choose between greater efficiency or cosmesis of the orthosis. Composite materials have the potential to permit the required rigidity in a structure that is less obtrusive. However, their material properties could lead to unsafe forms of failure unless suitable manufacturing methods are devised. It is therefore inappropriate to supply prototypes to patients for field evaluation until laboratory investigation of innovative production methods has ensured that the orthosis is safe. A production technique has been devised that is ostensibly suitable. Prototype body braces have been tested and have been shown to have improved structural properties and safe failure modes. A test programme implemented on a complete concept orthosis has confirmed that improved lateral rigidity can be achieved with a less obtrusive body brace, and that it will behave safely for long enough to permit field evaluation.

10 years of experience with endovascular AAA repair has yielded important information regarding the relationship between stent-graft design and stent-graft performance. Commercially available systems differ in important ways. General conclusions regarding endovascular AAA repair need to be qualified by reference to a specific system, or systems. Nevertheless, one can draw conclusions regarding the observed effects of certain design features, some of which are common to several devices. For example: tapered, trackable delivery systems (≤20 French in diameter) rarely fail to traverse tortuous iliac arteries: transmural barbs provide the most secure means of proximal attachment, column strength is of little value; proximal stent migration is becoming the primary late failure mode; modular stent-grafts are more versatile than unibody stent-grafts; fully-stented graft limbs are less prone to thrombosis than unstented graft limbs, iliac implantation and low porosity are associated with lower rates of aneurysm dilatation in the absence of endoleak (endotension); any movement between the angle of a stent and the overlying fabric will lead to graft erosion; unpolished (black) Nitinol is prone to fracture; and a long trunk/short limb combination is more stable than a short trunk/long limb combination.

Aesthetic prostheses must fulfill a functional as well as an aesthetic role. The function of these prostheses may be perceived as an additional passive support, or as an instrument of social function and an aid to the patient. This functional role has been observed in the continued use of these prostheses over several years. We reviewed our experience with prescription, fitting and follow-up care in 2847 patients. Classification of these patients was based on their age, level of amputation (with or without functional pinch) and cause of amputation. Analysis of the data ratifies our indications for prosthesis fitting. The long-term wearing of these aesthetic prostheses confirms their use as therapeutic tools.

To evaluate the functioning of the Durham hip joint wear simulator, the wear rates of ultra high molecular weight polyethylene (UHMWPE) and polytetrafluoroethylene (PTFE) acetabular cups articulating against 22 mm diameter cobalt-chromium-molybdenum (CoCrMo) femoral heads were studied. A wear test was conducted in a lubricant of distilled water at 37°C for a duration of 4.8 million cycles. The average penetration rate for the CoCrMo femoral heads against UHMWPE acetabular cups was 0.03mm/106cycles, while penetration rate for PTFE cups was some twenty times greater. These results are of a similar order of magnitude to other simulator studies in distilled water and are in a similar ratio to clinical data.

The generation of submicrometre sized polyethylene particles has been shown to be one of the major causes of osteolysis, loosening and failure of total replacement joints. It has been reported that intramedullary brushing of the femoral canal with polymer brushes prior to total hip arthroplasty results in the release of polymer particles into the femoral canal. The aim of this study was to isolate and characterize these particles on the basis of morphology and size and to determine whether these particles may play a role in osteolysis and loosening of the total hip prostheses. It was found that the majority of the particles shed by the polymer brushes were submicrometre in size and were similar in morphology to UHMWPE wear particles isolated from periprosthetic tissues. In addition, the majority of the particles released by the brushes were in the biologically active size range (0.1-10μm), and may contribute to osteolysis and loosening of hip prostheses.

This paper describes a method for measuring electrically elicited auditory reflex thresholds (EARTs) in young children who use the CLARION® Multi-Strategy™ Cochlear Implant. The EART is an objective measure that can guide the fitting of a cochlear implant in individuals who are unable to perform behavioral tasks required to program the device. Reflexes were obtained in 11 of 17 pediatric Clarion users. The EART current level indicated a point at which an auditory percept was present and the sound was loud, but not uncomfortable. The EART then was used as a basis for conditioning behavioral responses, and as a guideline for setting most comfortable loudness levels.

One of the main issues in hearing-aid fittings is the abnormal perception of the user’s own voice as too loud, “boomy,” or “hollow.” This phenomenon known as the occlusion effect be reduced by large vents in the earmolds or by open-fit hearing aids. This review provides an overview of publications related to open and closed hearing-aid fittings. First, the occlusion effect and its consequences for perception while using hearing aids are described. Then, the advantages and disadvantages of open compared with closed fittings and their impact on the fitting process are addressed. The advantages include less occlusion, improved own-voice perception and sound quality, and increased localization performance. The disadvantages associated with open-fit hearing aids include reduced benefits of directional microphones and noise reduction, as well as less compression and less available gain before feedback. The final part of this review addresses the need for new approaches to combine the advantages of open and closed hearing-aid fittings.

After amputation digital prostheses are infrequently used. With modern methods of fabrication both cosmetic and functional use are now possible. We have assessed the use of single digit prostheses in a district general hospital setting.

A discussion of the protocols used particularly in the clinical application of the Desired Sensation Level (DSL) Method is presented in this chapter. In the first section, the measurement and application of acoustic transforms is described in terms of their importance in the assessment phase of the amplification fitting process. Specifically, the implications of individual ear canal acoustics and their impact on accurately defining hearing thresholds are discussed. Detailed information about the statistical strength of the real-ear-to-coupler difference (RECD) measurement and how to obtain the measure in young infants is also provided. In addition, the findings of a study that examined the relationship between behavioral and electrophysiologic thresholds in real-ear SPL is described. The second section presents information related to the electroacoustic verification of hearing instruments. The RECD is discussed in relation to its application in simulated measurements of real-ear hearing instrument performance. In particular, the effects of the transducer and coupling method during the RECD measurement are described in terms of their impact on verification measures. The topics of insertion gain, test signals, and venting are also considered. The third section presents three summary tables that outline the hearing instrument fitting process for infants, children, and adults. Overall, this chapter provides both clinical and scientific information about procedures used in the assessment and verification stages of the DSL Method.