A more patient-friendly use of circular fixators in deformity correction

PURPOSE: The evaluation of a construction that allows the exchange of circular and unilateral external fixators on the same fixation pins to the bone in outpatient circumstances during bone lengthening and alignment procedures. METHODS: Nine children were treated with this concept. After bone lengthening and alignment, the circular fixators were exchanged for unilateral fixators in the outpatient clinic to hold the position of the bony parts during the consolidation phase. RESULTS: The decrease of time needed to use the circular fixator during the treatment was considered to be an improvement in comfort. CONCLUSIONS: The concept of using both a circular and a unilateral external fixator in a construction that allows the exchange of the external fixators in outpatient circumstances combines the advantages of both systems, and creates more options in the different stages of bone deformity correction. Patient comfort is increased by the decrease of time needed to use the circular fixator

Implementation by simulation; strategies for ultrasound screening for hip dysplasia in the Netherlands

Background: Implementation of medical interventions may vary with organization and available capacity. The influence of this source of variability on the cost-effectiveness can be evaluated by computer simulation following a carefully designed experimental design. We used this approach as part of a national implementation study of ultrasonographic infant screening for developmental dysplasia of the hip (DDH). Methods: First, workflow and performance of the current screening program (physical examination) was analyzed. Then, experimental variables, i.e., relevant entities in the workflow of screening, were defined with varying levels to describe alternative implementation models. To determine the relevant levels literature and interviews among professional stakeholders are used. Finally, cost-effectiveness ratios (inclusive of sensitivity analyses) for the range of implementation scenarios were calculated. Results: The four experimental variables for implementation were: 1) location of the consultation, 2) integrated with regular consultation or not, 3) number of ultrasound machines and 4) discipline of the screener. With respective numbers of levels of 3,2,3,4 in total 72 possible scenarios were identified. In our model experimental variables related to the number of available ultrasound machines and the necessity of an extra consultation influenced the cost-effectiveness most. Conclusions: Better information comes available for choosing optimised implementation strategies where organizational and capacity variables are important using the combination of simulation models and an experimental design. Information to determine the levels of experimental variables can be extracted from the literature or directly from experts

Acetabular rim extension using a personalized titanium implant for treatment of hip dysplasia in dogs: short-term results

Hip dysplasia (HD) is a common orthopedic problem in young dogs. To decrease the laxity of the hip joint related to HD, the surgical treatments are recommended to increase femoral head coverage. ACEtabular rim eXtension (ACE-X) using a personalized 3-dimensional printed titanium shelf implant is a new surgical treatment to increase femoral head coverage and decrease laxity of the dysplastic hip joint, however, the efficacy is less know. Client-owned dogs older than 6 months with clinical signs of coxofemoral joint subluxation and radiographic evidence of HD with no or mild osteoarthritis (OA) were included. The Norberg angle (NA), linear percentage of femoral head overlap (LFO), and percentage of femoral head coverage (PC) were investigated radiographically and with computed tomography (CT) before and after surgery. OA was graded (scores 0–3) according to the maximum osteophyte size measured on CT. In addition, joint laxity (Ortolani) test results, gait analysis, and the Helsinki chronic pain index (HCPI) questionnaire were obtained at preoperative, immediately postoperative and at 1.5- and 3-month evaluations. Acetabular rim extension was performed in 61 hips of 34 dogs; NA, LFO, and PC were significantly higher immediately postoperatively and at the 1.5- and 3-month follow-up examinations compared with preoperative values (p < 0.05). Osteophyte size gradually increased over time (p < 0.05). The OA score significantly increased between preoperatively and directly postoperatively, and between preoperatively and at 3-month follow-up (p < 0.05). The laxity test normalized in 59 out of 61 hips after surgery, and the HCPI questionnaire showed that the pain score decreased significantly at 1.5 and 3 months, postoperatively. The force plate showed no significant improvement during the 3 months follow-up. Although pain reduction by the implant was unclear in short-term results, a personalized shelf implant significantly increased femoral head coverage and eliminated subluxation of the dysplastic hip joint. Further studies are required to study the long-term efficacy of gait, chronic pain, and progression of osteoarthritis

Orthopaedic management of Hurler’s disease after hematopoietic stem cell transplantation: a systematic review

The introduction of hematopoietic stem cell transplantation (HSCT) has significantly improved the life-span of Hurler patients (mucopolysaccharidosis type I-H, MPS I-H). Yet, the musculoskeletal manifestations seem largely unresponsive to HSCT. In order to facilitate evidence based management, the aim of the current study was to give a systematic overview of the orthopaedic complications and motor functioning of Hurler's patients after HSCT. A systematic review was conducted of the medical literature published from January 1981 to June 2010. Two reviewers independently assessed all eligible citations, as identified from the Pubmed and Embase databases. A pre-developed data extraction form was used to systematically collect information on the prevalence of radiological and clinical signs, and on the orthopaedic treatments and outcomes. A total of 32 studies, including 399 patient reports were identified. The most frequent musculoskeletal abnormalities were odontoid hypoplasia (72%), thoracolumbar kyphosis (81%), genu valgum (70%), hip dysplasia (90%) and carpal tunnel syndrome (63%), which were often treated surgically during the first decade of life. The overall complication rate of surgical interventions was 13.5%. Motor functioning was further hampered due to reduced joint mobility, hand dexterity, motor development and longitudinal growth. Stem cell transplantation does not halt the progression of a large range of disabling musculoskeletal abnormalities in Hurler's disease. Although prospective data on the quantification, progression and treatment of these deformities were very limited, early surgical intervention is often advocated. Prospective data collection will be mandatory to achieve better evidence on the effect of treatment strategies

Bone mineral density in developing children with osteogenesis imperfecta

Background and purpose - Osteogenesis imperfecta (OI) is a heritable disorder of connective tissue caused by a defect in collagen type I synthesis. For bone, this includes fragility, low bone mass, and progressive skeletal deformities, which can result in various degrees of short stature. The purpose of this study was to investigate development of bone mineral density in children with OI. Patients and methods - Development of lumbar bone mineral density was studied retrospectively in a cohort of 74 children with OI. Mean age was 16.3 years (SD 4.3). In 52 children, repeated measurements were available. Mean age at the start of measurement was 8.8 years (SD 4.1), and mean follow-up was 9 years (SD 2.7). A longitudinal data analysis was performed. In the total cohort (74 children), a cross-sectional analysis was performed with the latest-measured BMD. Age at the latest BMD measurement was almost equal for girls and boys: 17.4 and 17.7 years respectively. Result - Mean annual increase in BMD in the 52 children was 0.038 g/cm(2)/year (SD 0.024). Annual increase in BMD was statistically significantly higher in girls, in both the unadjusted and adjusted analysis. In cross-sectional analysis, in the whole cohort the latest-measured lumbar BMD was significantly higher in girls, in the children with OI of type I, in walkers, and in those who were older, in both unadjusted and adjusted analysis. Interpretation - During 9 years of follow-up, there appeared to be an increase in bone mineral density, which was most pronounced in girls. One possible explanation might be a later growth spurt and older age at peak bone mass in boy