What Parents of Children Born with a Cleft Lip and/or Palate Want to Know About the Care for their Child.

OBJECTIVE: Adequate health information that matches the needs of care recipients is a prerequisite for patient-centered care. To facilitate the provision of tailored and timely information, it isimportant to understand the information needs of parents of children and adolescents with cleft lip and/or palate (CL/P) themselves, and in addition they were asked how they experienced the provided care-related information. DESIGN: A cross-sectional study employing questionnaires and semi-structured interviews. SETTING: Participants were recruited from a cleft palate-craniofacial care unit in a major tertiary hospital in the Netherlands. PARTICIPANTS: Participants were parents or guardians of children with CL/P, and two adolescents with CLP. They were recruited through the outpatient clinic during multidisciplinary consultation or after clinical admission. RESULTS: In total, fifty-five questionnaires were completed by parents or guardians and eleven interviews were conducted with nine parents of children with CL/P and two adolescents with CL/P. In general, participants reported to be satisfied with provided information during hospital admission or multidisciplinary cleft team consultations (mean 8.0, scale 0-10). In addition, 25.5% (n = 14) indicated that information to prepare for hospital admission was lacking (eg, practical information). Thematic qualitative analysis yielded five main information needs: 1) Clear communication during the care process, 2) Overview of the care trajectory, 3) Specific care plan information, 4) Presentation of information and 5) Guidance and support. CONCLUSIONS: Our findings emphasize the importance of gaining insights into wishes and information needs from care recipients who can provide insights in their information needs. With these findings, information provision should be redesigned to improve and to foster the further transition to family-centered care.

A usability evaluation of the perceived user friendliness, accessibility, and inclusiveness of a personalized digital care pathway tool.

OBJECTIVE: This study aimed to acquire insight into the perceived user friendliness, accessibility and inclusiveness of a personalized digital care pathway. MATERIALS & METHODS: Usability of the tool was tested in an experimental setting. Mixed methods data collection consisted of scenario-based eye tracking tests in a web- or mobile-based prototype of the tool, followed by a questionnaire assessing user friendliness (System Usability Scale; SUS) and a structured interview. Inclusiveness was assessed by subgroup comparisons based on language proficiency, age and education level. Via purposive sampling a heterogeneous population of users (N = 24) was recruited. Eye tracking was used to measure gaze behavior. RESULTS: Overall, participants were satisfied with the tool (scale 0-10, 7.5; SD = 1.29). User friendliness of the mobile version (68.3; SD = 21.6) was higher than the web version (50.9; SD = 17.3) measured by SUS score (0-100). With regard to accessibility, eye tracking scenarios showed that the menu bar was hard to find (17% mobile, 55% web). In all scenario's, information was found faster in the mobile version than the web version. Attention was easily drawn to images. Regarding inclusiveness of the tool, we found significantly longer completing time of the scenario tasks for low language proficiency (p-value = 0.029) and higher age subgroups (p-value = 0.049). Lower language proficiency scored a significant lower SUS score (p-value = 0.012). CONCLUSIONS: Overall, user friendliness and accessibility were positively evaluated. Assessment of inclusiveness emphasized the need for tailoring digital tools to those with low language proficiency and/or an older age. Co-creation of digital care tools with users is therefore important to match users' needs, make tools easily understandable and accessible to all users, and ultimately result in better uptake and impact.

The assessment of sexual wellbeing in treatment-seeking transgender individuals: a systematic review of the medical literature.

Sexual-wellbeing is recognized as an important aspect of quality-of-life. Yet, no overview exists of which aspects of sexual-wellbeing have been assessed in trans individuals seeking or undergoing medical treatment, nor is it clear what tools are used to evaluate the effect of medical treatment on sexual-wellbeing. First, to identify which topics pertaining to sexual-wellbeing have been assessed in transgender individuals in a medical context. Second, to determine which tools have been used for measuring aspects of sexual-wellbeing. A conceptual framework of sexual-wellbeing, was used as reference. A literature search (in PubMed, Embase, Cochrane Library) was performed up to March 10th, 2020. Studies that assessed aspects of sexual-wellbeing in transgender individuals' medical context were included in this review. Specific sexual topics addressed in each study were extracted by two independent reviewers. Thematic analysis was performed to identify sexual themes. Additionally, tools used to measure topics related to sexuality in transgender individuals were identified. In 172 papers, a total of 178 topics related to sexual-wellbeing were identified. Ten overarching themes were identified; sexuality, enacted sexual script, sexual activities, sexual relations, sexual response cycle, genital function, sexual function, sexual pleasure, sexual satisfaction, and quality-of-sex-life. Functional aspects of sexuality are assessed most frequently. A variety of methods was used to evaluate aspects related to sexual-wellbeing in trans individuals and over 50 different tools were identified. Self-developed questionnaires were used most frequently (n = 80), followed by chart reviews (n = 50), self-developed structured interviews (n = 37) and physical examination (n = 13). 23 previously developed questionnaires were used, all of which were developed for a cisgender population. Many studies in trans individuals touch on topics related to sexual-wellbeing, however, a comprehensive conceptualisation of (10 themes of) sexual-wellbeing is still lacking. Still, no valid tool exists for assessing sexual-wellbeing in the trans population, but is much needed.

Long-Term Changes in Free Nipple Graft Morphology and Patient-Reported Outcomes in Gender-Affirming Mastectomies.

BACKGROUND: After gender-affirming mastectomies with free nipple grafts, satisfaction with nipples tends to fall short behind chest outcomes. This might be related to changes in nipple areolar complex (NAC) dimensions over time. Therefore, the aim of this study is to establish the long-term changes in NAC morphology and compare these to cisgender male NAC outcomes. MATERIALS: An observational, cross-sectional study was performed. Data from two prospective cohorts were collected: (1) transgender men after a mastectomy with free nipple grafts and (2) cisgender men (reference sample). Demographics and 3-D images were collected for both groups. NAC measurements were performed on the 3-D images at 4 time points (7-, 30-, 90- and 365-days postoperative) in transgender men and once in cisgender men. Furthermore, the BODY-Q (nipple module) was administered postoperatively at 30-, 90- and 365-days in transgender men. RESULTS: In total, 67 transgender and 150 cisgender men were included. NAC width and height in trans men changed from 21.5 mm (±2.7) to 23.8 mm (±3.9, p<0.001) and 16.2 mm (±2.5) to 14.7 mm (±3.0, p=0.01) within a year, respectively. On average, the NACs increasingly rotated 21 degrees in the latero-caudal direction (p<0.001). The mean NAC width and height in cisgender men were 28.1 mm (±5) and 20.7 mm (±4), being significantly larger than in transgender men. Satisfaction for size, shape and flatness decreased significantly after postoperative day 30 (p=<0.05) in transgender men. CONCLUSIONS: Morphology of and satisfaction with the NACs in transgender men significantly changed over time. Understanding and incorporating these differences into pre-operative counseling and surgical planning might help increase patient satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The development of burn scar contractures and impact on joint function, disability and quality of life in low- and middle-income countries: A prospective cohort study with one-year follow-up.

OBJECTIVE: The aim of this study was to assess the development of burn scar contractures and their impact on joint function, disability and quality of life in a low-income country. METHODS: Patients with severe burns were eligible. Passive range of motion (ROM) was assessed using lateral goniometry. To assess the development of contractures, the measured ROM was compared to the normal ROM. To determine joint function, the normal ROM was compared to the functional ROM. In addition, disability and quality of life (QoL) were assessed. Assessments were from admission up to 12 months after injury. RESULTS: Thirty-six patients were enrolled, with a total of 124 affected joints. The follow-up rate was 83%. Limited ROM compared to normal ROM values was observed in 26/104 joints (25%) at 12 months. Limited functional ROM was observed in 55/115 joints (48%) at discharge and decreased to 22/98 joints (22%) at 12 months. Patients who had a contracture at 12 months reported more disability and lower QoL, compared to patients without a contracture (median disability 0.28 versus 0.17 (p = 0.01); QoL median 0.60 versus 0.76 (p = 0.001)). Significant predictors of developing joint contractures were patient delay and the percentage of TBSA deep burns. CONCLUSION: The prevalence of burn scar contractures was high in a low-income country. The joints with burn scar contracture were frequently limited in function. Patients who developed a contracture reported significantly more disability and lower QoL. To limit the development of burn scar contractures, timely access to safe burn care should be improved in low-income countries.

Within-patient randomized clinical trial comparing incisional negative-pressure wound therapy with suction drains in gender-affirming mastectomies.

BACKGROUND: Incisional negative-pressure wound therapy (iNPWT) is widely adopted by different disciplines for multiple indications. Questions about the most appropriate uses and value of iNPWT have been raised. METHODS: An open-label within-patient RCT was conducted in transgender men undergoing gender-affirming mastectomies. The objective was to determine the effect of iNPWT as a substitute for standard dressing and suction drains on wound healing complications. One chest side was randomized to receive the iNPWT intervention, and the other to standard dressing with suction drain. The primary endpoints were wound healing complications (haematoma, seroma, infection, and dehiscence) after three months. Additional outcomes were pain according to a numerical rating scale and patient satisfaction one week after surgery. RESULTS: Eighty-five patients were included, of whom 81 received both the iNPWT and standard treatment. Drain removal criteria were met within 24 h in 95 per cent of the patients. No significant decrease in wound healing complications was registered on the iNPWT side, but the seroma rate was significantly increased. In contrast, patients experienced both significantly less pain and increased comfort on the iNPWT side. No medical device-related adverse events were registered. CONCLUSION: Substituting short-term suction drains with iNPWT in gender-affirming mastectomies increased the seroma rates and did not decrease the amount of wound healing complications. Registration number: NTR7412 (Netherlands Trial Register).

The ideal location of the male nipple-areolar complex: A pinpointing algorithm.

Background: In the treatment of gender dysphoria, appropriate nipple-areola complex (NAC) positioning is essential for achieving a natural appearing male chest after subcutaneous mastectomy. An accurate predictive model for the ideal personalized position of the NAC is still lacking. The aim of this study is to determine the anthropometry of the male chest to create individualized guidelines for appropriate NAC positioning in the preoperative setting. Materials and methods: Cisgender male participants were recruited. Multiple chest measurements were manually recorded. Best subset regression using linear models was used to select predictors for the horizontal coordinate (nipple-nipple distance; NN) and vertical coordinate (sternal notch-nipple distance; SNN) of the NAC. Internal validation was assessed using bootstrapping. Furthermore, a cohort of transgender men who had received a mastectomy with replantation of nipples according to current practice was identified. Comparison testing between the algorithm and standard practice was performed to test the limitations of standard practice. Results: One hundred and fifty cis male participants were included (median age: 26, IQR: 22-34 years). Four predictors were found to predict NN (age, weight, chest circumference (CC), anterior-axillar fold to anterior-axillar fold (AUX-AUX)) and reads as follows: NN = 4.11 + 0.035*age + 0.041*weight + 0.093*CC + 0.140*AUX-AUX Two predictors were found to predict SNN (NN and weight), and reads as follows: SNN = 7.248 + 0.303*NN + 0.072*weight. Both models performed well (Bootstrapped R2: 0.63 (NN), 0.50 (SNN)) and outperformed previous models predicting NAC position. Ninety-six transgender men were eligible for evaluation of current practice and showed an average placement error of -0.9 cm for NN and +2.2 cm for SNN. Conclusion: The non-standardized approach of NAC repositioning results in a significant error of nipple placement. We suggest that the two predictive models for NN and SNN can be used to optimize NAC positioning on the masculinized chest wall.Supplemental data for this article is available online at https://doi.org/10.1080/26895269.2021.1884926.

Functional Outcomes and Urological Complications after Genital Gender Affirming Surgery with Urethral Lengthening in Transgender Men.

PURPOSE: We determined the urological complications and lower urinary tract function after genital gender affirming surgery with urethral lengthening in transgender men. MATERIALS AND METHODS: A single center, retrospective cohort study was performed from January 2013 to January 2018. Patient demographics, medical history, perioperative data, surgical and urological complications, and preoperative and postoperative urological outcomes were obtained. RESULTS: Of the 63 patients included in the study 8 (13%) underwent metoidioplasty and 55 (87%) phalloplasty, comprised of 27 (43%) free radial forearm flap, 19 (30%) anterolateral thigh flap and 9 (14%) superficial circumflex iliac artery perforator flap surgeries. In phalloplasty the types of urethral lengthening were tube-in-tube free radial forearm flap in 27 (49%), free radial forearm flap (second fasciocutaneous flap) in 18 (33%), superficial circumflex iliac artery perforator flap in 5 (9%) or labial in 5 (9%). Mean followup was 23 months (range 12 to 71). Stricture formation occurred in 35 (63%) phalloplasty and 5 (63%) metoidioplasty cases. Urethral fistula formation occurred in 15 (27%) phalloplasty and 4 (50%) metoidioplasty cases. Mean time to strictures and fistulas was approximately 3 months. Overall 46 (73%) patients needed revision surgery because of fistulas/strictures. After treatment 44 (70%) patients were able to void from the tip of the phallus. No clinically relevant differences in International Prostate Symptom Scores, frequency volume charts and uroflowmetry were found preoperatively vs postoperatively. CONCLUSIONS: Genital gender affirming surgery with urethral lengthening is a complex procedure with a high complication rate. After treating complications no clinically relevant differences in urological functioning were recorded. The majority of transgender men could void from the tip of the penis and showed favorable urological outcomes.

Short-term cost-effectiveness of one-stage implant-based breast reconstruction with an acellular dermal matrix versus two-stage expander-implant reconstruction from a multicentre randomized clinical trial.

BACKGROUND: Implant-based breast reconstruction (IBBR) is the most commonly performed reconstructive procedure and its economic impact is significant. This study aimed to analyse whether a direct one-stage IBBR with use of an acellular dermal matrix (ADM) is more cost-effective than two-stage (expander-implant) breast reconstruction. METHODS: The BRIOS (Breast Reconstruction In One Stage) study was an open-label multicentre RCT in which women scheduled for skin-sparing mastectomy and immediate IBBR were randomized between one-stage IBBR with ADM or two-stage IBBR. Duration of surgery and hospital stay, and visits for the primary surgery, unplanned and cosmetic procedures were recorded. Costs were estimated at an institutional level. Health status was assessed by means of the EuroQol Five Dimensions 5L questionnaire. RESULTS: Fifty-nine patients (91 breasts) underwent one-stage IBBR with ADM and 62 patients (92 breasts) two-stage IBBR. The mean(s.d.) duration of surgery in the one-stage group was significantly longer than that for two-stage IBBR for unilateral (2·52(0·55) versus 2·02(0·35) h; P < 0·001) and bilateral (4·03(1·00) versus 3·25(0·58) h; P = 0·017) reconstructions. Costs were higher for one-stage compared with two-stage IBBR for both unilateral (€12 448 (95 per cent c.i. 10 722 to 14 387) versus €9871 (9373 to 10 445) respectively; P = 0·025) and bilateral (€16 939 (14 887 to 19 360) versus €13 383 (12 414 to 14 669); P = 0·002) reconstructions. This was partly related to the use of relatively expensive ADM. There was no difference in postoperative health status between the groups. CONCLUSION: One-stage IBBR with ADM was associated with higher costs, but similar health status, compared with conventional two-stage IBBR. Registration number: NTR5446 ( http://www.trialregister.nl).

Predictors of complications after direct-to-implant breast reconstruction with an acellular dermal matrix from a multicentre randomized clinical trial.

BACKGROUND: In the multicentre randomized trial BRIOS (Breast Reconstruction In One Stage), direct-to-implant (DTI) breast reconstruction with an acellular dermal matrix (ADM) was associated with a markedly higher postoperative complication rate compared with two-stage tissue expander/implant breast reconstruction. This study aimed to identify factors that contribute to the occurrence of complications after DTI ADM-assisted breast reconstruction. METHODS: Data were obtained from the BRIOS study, including all patients treated with DTI ADM-assisted breast reconstruction. Logistic regression analyses were performed to identify factors predictive of postoperative complications. RESULTS: Fifty-nine patients (91 breasts) were included, of whom 27 (35 breasts) developed a surgical complication. Reoperations were performed in 29 breasts (32 per cent), with prosthesis removal in 22 (24 per cent). In multivariable analyses, mastectomy weight was associated with complications (odds ratio (OR) 1·94, 95 per cent c.i. 1·33 to 2·83), reoperations (OR 1·70, 1·12 to 2·59) and removal of the implant (OR 1·55, 1·11 to 2·17). Younger patients (OR 1·07, 1·01 to 1·13) and those who received adjuvant chemotherapy (OR 4·83, 1·15 to 20·24) more frequently required reoperation. In univariable analyses, adjuvant radiotherapy showed a trend towards more complications (OR 7·23, 0·75 to 69·95) and removal of the implant (OR 5·12, 0·76 to 34·44), without reaching statistical significance. CONCLUSION: Breast size appeared to be the most significant predictor of complications in DTI ADM-assisted breast reconstruction. The technique should preferably be performed in patients with small to moderate sized breasts. Registration number: NTR5446 ( http://www.trialregister.nl).

Autologous fat grafting in onco-plastic breast reconstruction: A systematic review on oncological and radiological safety, complications, volume retention and patient/surgeon satisfaction.

OBJECTIVE: This study presents an up-to-date overview of the literature on autologous fat grafting (AFG) in onco-plastic breast reconstruction, with respect to complications, oncological and radiological safety, volume retention and patient/surgeon satisfaction. BACKGROUND: Although AFG is increasingly being applied in onco-plastic breast reconstruction, a comprehensive overview of the available evidence for this procedure is still lacking. METHODS: A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was conducted. Case series, cohort studies and randomized controlled trials (RCTs) reporting on relevant outcomes of breast reconstruction with supplemental AFG were included. RESULTS: In total, 43 studies were included reporting on 6260 patients with a follow-up period ranging from 12 to 136 months. The average locoregional and distant oncological recurrence rates after breast reconstruction with AFG were 2.5% (95% confidence interval (CI) 1.7-3.7) and 2.0% (95% CI 1.1-3.5), respectively. Fewer cysts and calcifications were seen on radiological images for this procedure than for other types of breast surgery. However, more biopsies were performed based on radiological findings (3.7% vs. 1.6%), and more cases of fat necrosis (9.0% vs 4.7%) were seen after treatment with AFG. The total complication rate of 8.4% (95% CI 7.6-9.1) is lower than those reported following other reconstructive breast procedures. The mean volume retention was 76.8% (range 44.7-82.6%) with a satisfaction rate of 93.4% for patients and 90.1% for surgeons. CONCLUSIONS: AFG in breast reconstruction is a promising technique. Safety is not compromised as cancer recurrence and complications are not observed. Whether AFG interferes with radiological follow-up remains to be elucidated. Randomized trials with sound methodology are needed to confirm these conclusions.

Single-stage breast reconstruction using Strattice™: A retrospective study.

INTRODUCTION: Strattice™, a porcine acellular dermal matrix, has emerged as a product to augment implant-based breast reconstruction. It aims to resolve problems related to poor tissue coverage of the implant. Presently, evidence justifying the use of Strattice in breast reconstruction is lacking. The objective of this study is to assess the clinical outcomes of a patient cohort that underwent single-stage implant-based breast reconstruction with the additional use of Strattice. METHODS: We conducted a retrospective chart review of patients who underwent single-stage breast reconstruction with the use of Strattice. All cases of breast reconstruction after oncologic or prophylactic mastectomy between 2010 and 2014 in one of eight different centres in the Netherlands were included. Patient demographics, treatment characteristics and clinical outcome data were collected. The outcomes were presented using descriptive statistics, and the associations were evaluated using Fisher's exact test. RESULTS: Eighty-eight patients who underwent either unilateral (60 patients) or bilateral (25 patients) (n = 110 breasts) single-stage breast reconstruction with the use of Strattice were identified. The indication for mastectomy was therapeutic in 69.1% (76) of cases and prophylactic in 30.9% (34) of cases. The reported minor complications included seroma (20.9%), skin necrosis (20.0%), wound dehiscence (11.8%), erythema/inflammation (14.5%) and infection (11.8%). In 22 breasts (22.7%), reoperation was necessary, with explantation of the implant in 11 breasts (11.8%). CONCLUSIONS: In this cohort, the total complication rate was very high (78%). Although most complications were minor, reoperation was performed in 22.7%, with explantation of the implant in 11.8% of breasts. We suggest that patient selection, experience of the surgeon and handling of early complications are factors playing a crucial role in the success of the operation. The use of a Strattice sheet in single-stage implant-based breast reconstruction may be a promising technique, but more evidence from prospective, randomized studies is necessary to justify its use. LEVEL OF EVIDENCE: IV.

Long-Term Creep Behavior of the Intervertebral Disk: Comparison between Bioreactor Data and Numerical Results.

The loaded disk culture system is an intervertebral disk (IVD)-oriented bioreactor developed by the VU Medical Center (VUmc, Amsterdam, The Netherlands), which has the capacity of maintaining up to 12 IVDs in culture, for approximately 3 weeks after extraction. Using this system, eight goat IVDs were provided with the essential nutrients and submitted to compression tests without losing their biomechanical and physiological properties, for 22 days. Based on previous reports (Paul et al., 2012, 2013; Detiger et al., 2013), four of these IVDs were kept in physiological condition (control) and the other four were previously injected with chondroitinase ABC (CABC), in order to promote degenerative disk disease (DDD). The loading profile intercalated 16 h of activity loading with 8 h of loading recovery to express the standard circadian variations. The displacement behavior of these eight IVDs along the first 2 days of the experiment was numerically reproduced, using an IVD osmo-poro-hyper-viscoelastic and fiber-reinforced finite element (FE) model. The simulations were run on a custom FE solver (Castro et al., 2014). The analysis of the experimental results allowed concluding that the effect of the CABC injection was only significant in two of the four IVDs. The four control IVDs showed no signs of degeneration, as expected. In what concerns to the numerical simulations, the IVD FE model was able to reproduce the generic behavior of the two groups of goat IVDs (control and injected). However, some discrepancies were still noticed on the comparison between the injected IVDs and the numerical simulations, namely on the recovery periods. This may be justified by the complexity of the pathways for DDD, associated with the multiplicity of physiological responses to each direct or indirect stimulus. Nevertheless, one could conclude that ligaments, muscles, and IVD covering membranes could be added to the FE model, in order to improve its accuracy and properly describe the recovery periods.

Posterior lumbar interbody fusion using non resorbable poly-ether-ether-ketone versus resorbable poly-L-lactide-co-D,L-lactide fusion devices. Clinical outcome at a minimum of 2-year follow-up.

Previous papers on resorbable poly-L-lactide-co-D,L-lactide (PLDLLA) cages in spinal fusion have failed to report adequately on patient-centred clinical outcome measures. Also comparison of PLDLLA cage with a traditionally applicable counterpart has not been previously reported. This is the first randomized prospective study that assesses clinical outcome of PLDLLA cage compared with a poly-ether-ether-ketone (PEEK) implant. Twenty-six patients were randomly assigned to undergo instrumented posterior lumbar interbody fusion (PLIF) whereby either a PEEK cage or a PLDLLA cage was implanted. Clinical outcome based on visual analogue scale scores for leg pain and back pain, as well as Oswestry Disability Index (ODI) and SF-36 questionnaires were documented and analysed. When compared with preoperative values, all clinical parameters have significantly improved in the PEEK group at 2 years after surgery with the exception of SF-36 general health, SF-36 mental health and SF-36 role emotional scores. No clinical parameter showed significant improvement at 2 years after surgery compared with preoperative values in the PLDLLA patient group. Only six patients (50%) in the PLDLLA group showed improvement in the VAS scores for leg and back pain as well as the ODI, as opposed to 10 patients (71%) in the PEEK group. One-third of the patients in the PLDLLA group actually reported worsening of their pain scores and ODI. Three cases of mild to moderate osteolysis were seen in the PLDLLA group. Following up on our preliminary report, these 2-year results confirm the superiority of the PEEK implant to the resorbable PLDLLA implant in aiding spinal fusion and alleviating symptoms following PLIF in patients with degenerative spondylolisthesis associated with either canal stenosis or foramen stenosis or both and emanating from a single lumbar segment.

The results of downgrading moderate and severe slipped capital femoral epiphysis by an early Imhauser femur osteotomy.

PURPOSE: Patients with moderate and severe slipped capital femoral epiphysis (SCFE) develop osteoarthritis earlier in life in association with mechanical impingement. METHODS: To correct deformity and diminish impingement, we performed epiphysiodesis combined with an Imhauser intertrochanteric osteotomy (ITO) in moderate and severe slipped capital femoral epiphysis. We downgraded the angle of the head relative to the acetabulum into an angle corresponding to a mild slip or even an anatomical position. Our hypothesis is that the avoidance of anterior impingement at an early stage can prevent the development of osteoarthritis. RESULTS: The results of 28 patients (32 hips) were evaluated. Outcome parameters were SF-36, Harris Hip Score, range of motion, Kellgren-Lawrence score, chondrolysis and avascular necrosis. After a median follow-up of 8 (range 2-25) years, the group was clinically, functionally and socially performing well. Radiologically, there was no sign of chondrolysis or avascular necrosis, and more than 80% of the patients did not show any signs of osteoarthritis. CONCLUSIONS: Based on these results, we conclude that a one-stage Imhauser ITO combined with epiphysiodesis performed on patients with moderate and severe SFCE gives satisfactory results.

Resorbability of rigid beta-tricalcium phosphate wedges in open-wedge high tibial osteotomy: a retrospective radiological study.

The open-wedge high tibial osteotomy (OWHTO) is a well accepted treatment modality for patients with osteoarthritis of the medial compartment associated with genu varum. To fill in the osteotomy gap 30% macroporosity rigid beta-tricalcium phosphate (beta-TCP) is frequently used as a stable resorbable bone substitute. However, the resorbability of these beta-TCP wedges is not known. The aim of this study was to investigate this. Twenty-one OWHTO procedures in seventeen patients were performed with the use of 30% macroporosity rigid beta-TCP wedges. The osteotomies were fixed using an angle-stable locking plate. Conventional AP and lateral radiographs were examined in order to assess the resorbability of the 30% macroporosity rigid beta-TCP wedges as a function of time. A radiological classification system consisting of five phases was used to monitor the resorption of the 30% macroporosity rigid beta-TCP wedges. The mean duration of follow-up was 62 months (+/-23 range of 28-99). In all 21 cases, remnants of the 30% macroporosity rigid beta-TCP wedges were still present at maximum follow-up. Although the boundaries between 30% macroporosity rigid beta-TCP wedges and bone remained slightly visible, all osteotomies were completely consolidated and full osseointegration took place. In 16 out of 21 knees the fixation system was removed after a mean duration of 32 months (+/-19 range of 6-62). In six out of 21 knees a conversion to a knee arthroplasty was performed after a mean duration of 56 months (+/-18 range of 37-82). The OWHTO did not interfere with the placement of knee prostheses. Complete resorption of 30% macroporosity rigid beta-TCP wedges did not take place up to 8 years after operation.

Mechanobiology of bone tissue.

In order to obtain bones that combine a proper resistance against mechanical failure with a minimum use of material, bone mass and its architecture are continuously being adapted to the prevailing mechanical loads. It is currently believed that mechanical adaptation is governed by the osteocytes, which respond to a loading-induced flow of interstitial fluid through the lacuno-canalicular network by producing signaling molecules. An optimal bone architecture and density may thus not only be determined by the intensity and spatial distribution of mechanical stimuli, but also by the mechanoresponsiveness of osteocytes. Bone cells are highly responsive to mechanical stimuli, but the critical components in the load profile are still unclear. Whether different components such as fluid shear, tension or compression may affect cells differently is also not known. Although both tissue strain and fluid shear stress cause cell deformation, these stimuli might excite different signaling pathways related to bone growth and remodeling. In order to define new approaches for bone tissue engineering in which bioartificial organs capable of functional load bearing are created, it is important to use cells responding to the local forces within the tissue, whereby biophysical stimuli need to be optimized to ensure rapid tissue regeneration and strong tissue repair.

Differences in osteocyte density and bone histomorphometry between men and women and between healthy and osteoporotic subjects.

Bone defects related to osteoporosis develop with increasing age and differ between males and females. It is currently thought that the bone remodeling process is supervised by osteocytes in a strain-dependent manner. We have shown an altered response of osteocytes from osteoporotic patients to mechanical loading, and osteocyte density is reduced in osteoporotic patients, which might relate to imperfect bone remodeling, leading to lack of bone mass and strength. Hence, information on osteocyte density will contribute to a better understanding of bone biology in males and females and to the assessment of osteoporosis. Osteocyte density as well as conventional histomorphometric parameters of trabecular bone were determined in cancellous iliac crest bone of healthy postmenopausal women and men and of osteoporotic women and men. Osteocyte density was higher in healthy females than in healthy males and lower in osteoporotic females than in healthy females. Bone mass was reduced in osteoporotic patients, both male and female. In females, trabecular number was reduced, whereas in males, trabecular thickness was reduced and eroded surface was increased. There were no correlations between the parameter groups bone architecture, bone formation, bone resorption, and osteocyte density. These results are consistent with impaired osteoblast function in osteoporotic patients and with a different mechanism of bone loss between men and women, in which osteocyte density might play a role. The reduced osteocyte numbers in female osteoporotic patients might relate to imperfect bone remodeling leading to lack of bone mass and strength.

Mechanotransduction of bone cells in vitro: mechanobiology of bone tissue.

Mechanical force plays an important role in the regulation of bone remodelling in intact bone and bone repair. In vitro, bone cells demonstrate a high responsiveness to mechanical stimuli. Much debate exists regarding the critical components in the load profile and whether different components, such as fluid shear, tension or compression, can influence cells in differing ways. During dynamic loading of intact bone, fluid is pressed through the osteocyte canaliculi, and it has been demonstrated that fluid shear stress stimulates osteocytes to produce signalling molecules. It is less clear how mechanical loads act on mature osteoblasts present on the surface of cancellous or trabecular bone. Although tissue strain and fluid shear stress both cause cell deformation, these stimuli could excite different signalling pathways. This is confirmed by our experimental findings, in human bone cells, that strain applied through the substrate and fluid flow stimulate the release of signalling molecules to varying extents. Nitric oxide and prostaglandin E2 values increased by between two- and nine-fold after treatment with pulsating fluid flow (0.6 +/- 0.3 Pa). Cyclic strain (1000 microstrain) stimulated the release of nitric oxide two-fold, but had no effect on prostaglandin E2. Furthermore, substrate strains enhanced the bone matrix protein collagen I two-fold, whereas fluid shear caused a 50% reduction in collagen I. The relevance of these variations is discussed in relation to bone growth and remodelling. In applications such as tissue engineering, both stimuli offer possibilities for enhancing bone cell growth in vitro.

Effect of mechanical set point of bone cells on mechanical control of trabecular bone architecture.

The architecture of trabecular bone is thought to be controlled by mechanosensitive bone cells, where hormones provide a background for their responses to mechanical signals. It has been suggested that, in osteoporosis, this response is hampered by changed hormonal levels, thereby increasing the mechanical set point of the cells, which would lead to bone loss. We have investigated if a temporary increase of the mechanical set point causes deterioration of trabecular bone architecture, such as seen in osteoporosis. Furthermore, the effects of a changed loading pattern were investigated for the same reason. For this purpose, we used a computer simulation model, which was based on the regulation of bone architecture by mechanosensitive osteocytes. It was found that a temporary shift of the mechanical set point causes no lasting changes in architecture. Although an increase of the mechanical set point induces bone loss, the mechanism of bone loss (trabecular thinning) differs from what is observed in osteoporosis (loss of whole trabeculae). Hence, a change of the mechanical set point alone cannot explain bone loss as seen in osteoporosis. On the other hand, the removal of load components in a particular direction resulted in irreversible loss of whole trabeculae. These results indicate that such temporary changes in loading patterns could be important risk factors for osteoporosis.