Auricular reconstruction using biofabrication-based tissue engineering strategies

Auricular malformations, which impose a significant social and psychological burden, are currently treated using ear prostheses, synthetic implants or autologous implants derived from rib cartilage. Advances in the field of regenerative medicine and biofabrication provide the possibility to engineer functional cartilage with intricate architectures and complex shapes using patient-derived or donor cells. However, the development of a successful auricular cartilage implant still faces a number of challenges. These challenges include the generation of a functional biochemical matrix, the fabrication of a customized anatomical shape, and maintenance of that shape. Biofabrication technologies may have the potential to overcome these challenges due to their ability to reproducibly deposit multiple materials in complex geometries in a highly controllable manner. This topical review summarizes this potential of biofabrication technologies for the generation of implants for auricular reconstruction. In particular, it aims to discuss how biofabrication technologies, although still in pre-clinical phase, could overcome the challenges of generating and maintaining the desired auricular shapes. Finally, remaining bottlenecks and future directions are discussed.

Pressure effects on the nose by an in-flight oxygen mask during simulated flight conditions

BACKGROUND

Dutch F-16 fighter pilots experience oxygen mask inflicted nasal trauma, including discomfort, pain, skin abrasions, bruises and bone remodelling. Pressure and shear forces on the nose might contribute to causing these adverse effects. In this study, it was evaluated how flight conditions affected the exerted pressure, and whether shear forces were present.

METHODS

The pressure exerted by the oxygen mask was measured in 20 volunteers by placing pressure sensors on the nose and chin underneath the mask. In the human centrifuge, the effects on the exerted pressure during different flight conditions were evaluated (+3G_z, +6G_z, +9G_z, protocolised head movements, mounted visor or night vision goggles, NVG). The runs were recorded to evaluate if the mask's position changed during the run, which would confirm the presence of shear forces.

RESULTS

Head movements increased the median pressure on the nose by 50 mm Hg and on the chin by 37 mm Hg. NVG, a visor and accelerative forces also increased the median pressure on the nose. Pressure drops on the nose were also observed, during mounted NVG (-63 mm Hg). The recordings showed the mask slid downwards, especially during the acceleration phase of the centrifuge run, signifying the presence of shear forces.

CONCLUSIONS

The exerted pressure by the oxygen mask changes during different flight conditions. Exposure to changing pressures and to shear forces probably contributes to mask-inflicted nasal trauma.

The effect of lower extremity nerve decompression on health-related quality of life and perception of pain in patients with painful diabetic polyneuropathy: a prospective randomized trial

AIMS

The aim of this study was to assess whether surgical decompression of nerves in the lower extremity in people with painful diabetic polyneuropathy would have an effect on health-related quality of life and to determine minimal clinically important differences in pain and quality of life scores.

METHODS

The design was a randomized controlled trial in which 42 participants with painful diabetic painful neuroapthy underwent unilateral decompression of nerves in their left or right leg, using the other leg as a control, with 12 months follow-up. Surgical decompression was performed at the tibial, superficial, deep and common peroneal nerves. Preoperatively, and at 6 and 12 months post operatively, a visual analogue scale for pain and the 36 item short-form health survey and EuroQual 5 Dimensions questionnaires were completed.

RESULTS

At 12 months follow-up, the visual analogue scale was significantly reduced, but decompression surgery did not significantly alter health-related quality of life scores. The minimal clinically important difference for visual analogue scale reduction was determined at 2.9 points decrease, a threshold reached by 42.5% of the study population.

CONCLUSIONS

Although decompression surgery does not influence health-related quality of life, it achieves a clinically relevant reduction of pain in ~42.5% of people with diabetic peripheral neuropathy. It can therefore be considered for patients who do not adequately respond to pain medication.

A pragmatic approach to infants with Robin sequence: a retrospective cohort study and presence of a treatment algorithm

Objectives

Initial approaches to and treatments of infants with Robin sequence (RS) is diverse and inconsistent. The care of these sometimes critically ill infants involves many different medical specialties, which can make the decision process complex and difficult. To optimize the care of infants with RS, we present our institution’s approach and a review of the current literature.

Material and methods

A retrospective cohort study was conducted among 75 infants diagnosed with RS and managed at our institution in the 1996–2012 period. Additionally, the conducted treatment regimen in this paper was discussed with recent literature describing the approach of infants with RS.

Results

Forty-four infants (59 %) were found to have been treated conservatively. A significant larger proportion of nonisolated RS infants than isolated RS infants needed surgical intervention (53 vs. 25 %, p = .014). A mandibular distraction was conducted in 24 % (n = 18) of cases, a tracheotomy in 9 % (n = 7), and a tongue–lip adhesion in 8 % (n = 6). Seventy-seven percent of all infants had received temporary nasogastric tube feeding. The literature review of 31 studies showed that initial examinations and the indications to perform a surgical intervention varied and were often not clearly described.

Conclusions

RS is a heterogenic group with a wide spectrum of associated anomalies. As a result, the decisional process is challenging, and a multidisciplinary approach to treatment is desirable. Current treatment options in literature vary, and a more uniform approach is recommended.

Clinical Relevance

We provide a comprehensive and pragmatic approach to the analysis and treatment of infants with RS, which could serve as useful guidance in other clinics.

Professional opinion on oral cleft during pregnancy: a comparison between Israel and The Netherlands

OBJECTIVE

The aim of this study was to assess the opinion of obstetric care providers who perform prenatal ultrasounds to screen for anomalies and who advise women about their options, including termination of pregnancy, when an oral cleft is detected. We compared providers' opinions about pregnancy termination for isolated oral cleft in The Netherlands, where the number of terminations is low, and in Israel, where the number is high.

METHODS

Online questionnaires were used. The questions assessed the providers' views regarding the estimated burden of treatment, the functioning ability, and the level of happiness of children with an oral cleft and their parents. Additionally, we assessed providers' opinions on pregnancy termination for isolated oral cleft.

RESULTS

In The Netherlands, more professionals considered oral cleft a disability (rate differences 17.8%, 95% confidence interval: 0.5-33.1%) than in Israel. In the Netherlands, 10.6% of respondents (compared with 11.1% in Israel) thought that an isolated cleft was a reason for terminations of pregnancy (TOP) (rate differences 0.6%, 95% confidence interval: -12% to 10.9%).

CONCLUSIONS

Prenatal care providers in The Netherlands and Israel do not differ in their opinions about the severity of oral cleft and the acceptability of TOP for an isolated oral cleft. This study shows that prenatal care providers' attitudes do therefore not explain the dramatic difference between these countries in the number of TOP for isolated oral cleft.

Conservative treatment of thumb base osteoarthritis: a systematic review

PURPOSE

To provide a systematic review of randomized controlled trials regarding the conservative treatment of thumb base osteoarthritis (OA).

METHODS

A systematic literature search was conducted in the electronic bibliographic databases Medline (Pubmed) and Embase (both starting year to May 2014) using predetermined criteria for studies on nonoperative treatment of thumb base OA.

RESULTS

Twenty-three articles fulfilled our inclusion criteria. Systematic evaluation demonstrated the following: (1) Hand therapy can possibly reduce pain. However, owing to the lack of good-quality (randomized controlled) trials with sufficient follow-up time, no proper conclusions can be drawn. (2) Although both steroid and hyaluronate intra-articular injections can provide pain relief, most authors conclude that injection of hyaluronate is more effective. Follow-up is rather short with a maximum of 12 months in 1 study. Furthermore, study comparison is hampered by heterogeneity of study design and outcome parameters. (3) The use of orthoses reduces pain without effect on function, strength, or dexterity. Included studies used various types of orthoses. Follow-up times varied (2 wk-7 y). (4) There is no justification for the use of transdermal steroid delivery. (5) There is insufficient evidence justifying the use of leech therapy. (6) There are no high-level evidence studies specifically evaluating the effect of analgesics and patient education in joint protection in patients with thumb base OA.

CONCLUSIONS

There are only a few high-quality studies addressing the conservative treatment of trapeziometacarpal OA. Available evidence suggests only some effect of orthoses and intra-articular hyaluronate or steroid injections.

Effect of surgical decompression of nerves in the lower extremity in patients with painful diabetic polyneuropathy on stability: a randomized controlled trial

OBJECTIVE

To investigate the effect of decompression of nerves in the lower extremity in patients with painful diabetic polyneuropathy on static balance using a sensitive pressure mat system.

DESIGN

Non-blinded randomized controlled trial.

SETTING

Single center study performed at the University Medical Center Utrecht between 2010-2013.

SUBJECTS

Patients with painful diabetic polyneuropathy assessed with the Diabetic Neuropathy Symptom score and Diabetic Neuropathy Examination between 18-90 years. Exclusion criteria were: physical problems leading to instability, BMI>35 kg/m2, ankle fractures in history, amputations proximal to the tarsometatarsal joints, active foot ulcer(s), severe occlusive peripheral vascular diseases.

INTERVENTION

Unilateral surgical nerve decompression at four sites in the lower extremity, the contralateral limb was used as control (within-patient comparison), with one year follow-up.

MAIN MEASURES

Preoperatively and 6 and 12 months postoperatively, weight bearing and five variables of sway of the center of pressure were measured with a pressure mat with eyes open and eyes closed. T-test was used for evaluation of postoperative results.

RESULTS

Thirty-nine Patients met inclusion criteria and were enrolled for stability testing. Postoperatively no significant differences for sway variables and weight bearing were seen compared to preoperatively measurements.

CONCLUSIONS

There is no evidence that surgical decompression of nerves of the lower extremity influences stability within one year after surgery in patients with painful diabetic polyneuropathy.

Impact of laparoscopy for diagnosis and treatment in patients with disorders of sex development

OBJECTIVE

To review laparoscopy in patients with disorders of sex development (DSD) in order to clarify its usefulness in diagnosis, devising subsequent therapeutic strategies and managing patients with various conditions.

PATIENTS AND METHODS

Between April 1992 and December 2012, 29 laparoscopic surgeries were performed in 25 DSD patients. Among them, ten were diagnostic laparoscopy including gonadal biopsy, and 19 were therapeutic laparoscopy. Surgical procedures and complications were evaluated.

RESULTS

For diagnostic laparoscopy, laparoscopic gonadal biopsy was performed in three patients. Inspection, with or without open gonadal biopsy, was performed on four out of seven patients with 46XY DSD or mixed gonadal dysgenesis (MGD). Additional surgery was planned and performed based on diagnostic laparoscopic findings in six out of seven patients. In the three patients with ovotesticular DSD, the gonadal pathology was diagnosed as: testis/ovary in one, testis/ovotestis in one and ovary/ovotestis in one--this was from the laparoscopic inspection and/or gonadal biopsy. However, the final diagnoses were bilateral ovotestis in two patients and ovary/ovotestis in one patient. For therapeutic laparoscopy, surgical procedures were: gonadectomy in 17 patients (bilateral in 13, unilateral in three, partial in two); hysterectomy in two patients; orchiopexy in one; and sigmoid vaginoplasty in one patient (included multiple procedures). There were no severe perioperative complications. In the four patients with a history of diagnostic laparoscopy, no severe intra-abdominal adhesions that would disturb therapeutic laparoscopic surgery were observed.

CONCLUSION

While diagnostic laparoscopy was helpful in devising a therapeutic surgical strategy in most of the patients with DSD who were suspected as having complex gonadal status or Müllerian duct derivatives, attention must be paid to precisely diagnosing the gonadal status in ovotesticular DSD. On the other hand, therapeutic laparoscopic surgeries were valuable procedures in treating DSD patients, even with a history of previous diagnostic laparoscopy.

Exerted pressure by an in-flight oxygen mask

BACKGROUND

F-16 pilots wear an in-flight oxygen mask to prevent hypoxemia. In the contact area with the mask, the pilots experience nasal discomfort and pain, and may even develop nasal deformities. A likely cause is the pressure exerted by the mask. In this study the hypothesis was that the change in pressure exerted on the nose would be higher than on the chin, an area free of symptoms.

METHODS

Six F-16 pilots and five healthy former F-16 pilots volunteered to participate in this observational pilot study. At baseline the pilots donned mask and helmet. The median delta pressure (deltap) recordings at baseline were compared to the exerted deltap during the experimental head movements.

RESULTS

At baseline, there was no significant difference between the median deltap on the nose and chin (2 vs. 1.6 mmHg, T = 2). Head movements increased the median deltap on the nose by 50 mmHg (T = 0) and on the chin by 31 mmHg (T = 0) when compared to baseline. Head movements also decreased the pressure by -20 mmHg (T = 1.75) on the nose and -11 mmHg (T = 0) on the chin.

CONCLUSIONS

The data show that the baseline deltap is higher on the nose than on the chin. The head movements both increased and decreased the exerted pressure on the nose and the chin. These observations suggest that further evaluation of the effect of flight conditions on the exerted pressure is worthwhile to understand its contribution to the nasal symptoms.

Microtia in the Netherlands: clinical characteristics and associated anomalies

BACKGROUND

In Europe there have been few detailed reports on the clinical characteristics of microtia patient populations. The objective of the present study is to contribute to our insight of microtia in Europe by examining the Dutch microtia population treated in the University Medical Center Utrecht (UMCU) with regards to its clinical features and associated anomalies. In addition, an overview of the literature is provided for thorough comparison.

METHODS

A retrospective chart review was performed for all microtia patients referred to the UMCU for reconstructive surgery of the auricle over the period 1990-2012. Previous studies were identified by a systematic search of the electronic literature databases PubMed and Embase. In a subsequent meta-analysis the results from the literature review were pooled by geographical region to facilitate comparison.

RESULTS

A total of 204 microtia patients were referred for reconstructive surgery during 1990-2012. This group was characterized by a male predominance of 60.8%. Unilateral disease was observed in 91.7% of patients, affecting the right auricle in 66.3%. In unilateral patients lobule type microtia was seen in 59.9%, (small) concha type in 34.4% and anotia in 5.7%. The more frequent anomalies associated with microtia were atresia of the acoustic meatus (76.0%), preauricular skin tags (30.5%), hemifacial microsomia (27.5%), facial nerve paralysis (8.3%) and congenital heart disease (2.5%). Familial occurrence of microtia was reported for 2.0% of UMCU patients and for 10.0% of patients in the literature.

CONCLUSION

The clinical characteristics of microtia in the Netherlands correspond to those reported for other patient populations in the literature. Most congenital anomalies associated with microtia in Dutch patients belong to the Oculo-Auriculo-Vertebral Spectrum. The considerable degree of familial microtia observed in the literature points to a substantial genetic component in the etiology of the condition.

The fixation of a collagen type I/III membrane in the distal radioulnar joint of a human cadaver model

Damage to the cartilage of the distal radioulnar joint frequently leads to pain and limitation of movement, therefore repair of this joint cartilage would be highly desirable. The purpose of this study was to investigate the fixation of scaffold in cartilage defects of this joint as part of matrix-assisted regenerative autologous cartilage techniques. Two techniques of fixation of collagen scaffolds, one involving fibrin glue alone and one with fibrin glue and sutures, were compared in artificially created cartilage defects of the distal radioulnar joint in a human cadaver. After being subjected to continuous passive rotation, the methods of fixation were evaluated for cover of the defect and pull out force. No statistically significant differences were found between the two techniques for either cover of the defect or integrity of the scaffold. However, a significantly increased mean pull out force was found for the combined procedure, 0.665 N (0.150 to 1.160) versus 0.242 N (0.060 to 0.730) for glue fixation (p = 0.001). This suggests that although successful fixation of a collagen type I/III scaffold in a distal radioulnar joint cartilage defect is feasible with both forms of fixation, fixation with glue and sutures is preferable.

T-bar reconstruction of constricted ears and a new classification

For the correction of constricted ears, many techniques are described in the literature, the majority based on Tanzer's classification of 1975. The improvements in ear reconstruction published by Brent, Nagata, Firmin and Park make better outcomes possible. It is therefore that a new classification for constricted ears is proposed, together with an alternative technique for correction of group IIA and IIB deformities, using a T-strut of costal cartilage to reconstruct the underdeveloped or missing superior crus of the antihelix.

Ultrasound findings after surgical decompression of the tarsal tunnel in patients with painful diabetic polyneuropathy: a prospective randomized study

OBJECTIVE

It has been hypothesized that the development of diabetic polyneuropathy (DPN) is due to swelling of the nerve, as well as thickening and stiffening of the surrounding ligaments, causing chronic compression of nerves. We aimed to examine the effect of surgical decompression of the tibial nerve on the mean cross-sectional area (CSA).

RESEARCH DESIGN AND METHODS

We performed a randomized controlled trial of 42 subjects with painful DPN diagnosed using the Diabetic Neuropathy Score. A computer randomized for the surgery arm of the study. A control group consisting of 38 healthy subjects was included. An experienced sonographer measured the CSA and thickness-to-width (T/W) ratio of the tibial nerve, as well as the thickness of the flexor retinaculum.

RESULTS

CSA is significantly larger in patients with painful DPN (8.4 ± 3.9 mm(2)) than in control subjects (6.4 ± 1.3 mm(2)), P = 0.007. The T/W ratio in patients with painful DPN is 0.64 and in control subjects 0.59, P = 0.03. Patients with DPN have a significantly thicker retinaculum (1.07 mm) than control subjects (0.84 mm), P < 0.001. Mean follow-up was 28.2 weeks (range 23-45). Difference between baseline and follow-up in the operated leg was 1.49 mm(2) and in the control leg 1.81 mm(2), P = 0.674.

CONCLUSIONS

Decompression of the tibial nerve does not result in a significant difference between baseline and follow-up in CSA using ultrasound between the operated and control leg. Ultrasound measurements show a significantly increased CSA, a significantly thicker retinaculum, and a significantly increased T/W ratio in patients with painful DPN compared with healthy control subjects. Clinical trial reg. no. NTR2344, www.trialregister.nl.

Oxygen mask fit analysis in F-16 fighter pilots using 3D imaging

BACKGROUND

The majority of Dutch F-16 pilots experience in-flight oxygen mask related nasal discomfort and injury. We aimed to analyze the fit of the oxygen mask.

METHODS

We successfully scanned 35 pilots with a 3D scanner to measure the distance between the contact area on the nose and the oxygen mask in seven points, and the difference (delta) in angle between the nose and the mask relative to the facial midline. Ill fit was defined as > or = 4 mm distance, or delta > or = 4 degree angle. Intraclass correlation coefficients were used to objectify the reproducibility of the measurements.

RESULTS

There were 35 pilots who had > or = 4 mm distance between the nasal dorsum and the mask and 14 pilots had delta > or = 4 degree angle. Reproducibility of the distance measurements was excellent (R > or = 0.93, CI 95% 0.86-0.96) and of the angle measurements was good (R = 0.72, CI 95% 0.5-0.8).

CONCLUSION

The room for displacement that we found may be a contributor to the discomfort. It is indicative of an ill fit of the oxygen mask, since all subjects had complaints. We recommend evaluating whether improved fixation of the mask and simultaneous reduction of the pressure on the nose will improve comfort.

Prevalence of feeding disorders in children with cleft palate only: a retrospective study

OBJECTIVES

The purpose of this study in children with cleft palate only (CPO) is to (1) explore the prevalence of feeding problems on a retrospective basis, (2) investigate rates of nasogastric (NG) feeding, (3) examine the prevalence of associated disorders and/or syndromes (AssD/S), (4) investigate if there are certain risk factors associated with feeding difficulties, NG feeding, and failure of breastfeeding, and (5) investigate the effect of palatoplasty on feeding difficulties.

MATERIALS AND METHODS

In total, 90 questionnaires were included in this study. The medical records were reviewed.

RESULTS

Feeding difficulties were reported in 67% (n = 60) of all cases. NG feeding was given in 32% (n = 28) of all children. Forty-nine children (54%) have associated malformations. There is no significant relation for gender, gestational age, and birth weight as risk factors for feeding difficulties, NG feeding, and failure of breastfeeding. The severity of the cleft is significantly related to the prevalence of AssD/S. After palatoplasty, feeding difficulties improved in 79% of the CPO children.

CONCLUSIONS AND CLINICAL RELEVANCE

First, our results clearly indicate that children with CPO are at high risk of developing feeding difficulties (67%); NG feeding is often necessary (32%). Second, our results also indicate that the more severe the cleft, the more likely the chance for AssD/S. Third, the severity of the cleft is significantly related to the prevalence of AssD/S. Fourth, there is no significant relation for gender, gestational age, and birth weight as risk factors for feeding difficulties, NG feeding, and failure of breastfeeding. Fifth, improvement of feeding difficulties after surgery supports the importance of the soft palate closure in relation to sucking patterns and feeding skills.

Inflammatory mediators in posttraumatic radiocarpal osteoarthritis

PURPOSE

To identify the mediator profile in healthy, pre-osteoarthritis (OA) and end-stage OA radiocarpal joints. We hypothesized that there would be an increase in soluble mediators in posttraumatic wrist OA.

METHODS

We obtained radiocarpal synovial fluid samples from 3 groups of patients: healthy control (n = 12) samples were collected during wrist ganglion resection; pre-osteoarthritic (n = 16) samples, during a 3-ligament tenodesis procedure for complete scapholunate dissociation; and end-stage OA (n = 20) samples in patients with proven radiological OA changes. Using a multiplex enzyme-linked immunosorbent assay, we measured 12 mediators: interleukin (IL)-1β, tumor necrosis factor-α, oncostatin-M, interferon-γ, IL-4, IL-6, IL-7, IL-8, IL-10, IL-13, IL-1RA, and osteoprotegerin. Statistical analysis was performed using analysis of variance and Bonferroni-corrected post hoc tests.

RESULTS

Mediators IL-6, IL-10, and interferon-γ were increased in OA wrists compared to healthy and pre-OA samples. Tumor necrosis factor-α, oncostatin-M, osteoprotegerin, IL-8, and IL-1RA were detected but not at increased levels in OA wrists. We found no differences between healthy and pre-OA joints in all 12 mediators. Mediators IL-4, IL-7, IL-13, and IL-1β were not detected in either healthy, pre-OA or end-stage OA samples.

CONCLUSIONS

We identified no differences between healthy and pre-OA samples, suggesting no alteration in inflammatory status at the time of the 3-ligament tenodesis procedure. Consequently, mechanical disturbance seems to be the driving force toward OA and OA-associated inflammation in this stage of scapholunate dissociation. Increased levels of interferon-γ, IL-6, and IL-10 confirm inflammatory changes in the mechanically disturbed posttraumatic radiocarpal joint.