Mid-term results of autologous matrix-induced chondrogenesis for large chondral defects in hips with femoroacetabular impingement syndrome.

Aims: The purpose of this study was to evaluate the mid-term outcomes of autologous matrix-induced chondrogenesis (AMIC) for the treatment of larger cartilage lesions and deformity correction in hips suffering from symptomatic femoroacetabular impingement (FAI). Methods: This single-centre study focused on a cohort of 24 patients with cam- or pincer-type FAI, full-thickness femoral or acetabular chondral lesions, or osteochondral lesions ≥ 2 cm2, who underwent surgical hip dislocation for FAI correction in combination with AMIC between March 2009 and February 2016. Baseline data were retrospectively obtained from patient files. Mid-term outcomes were prospectively collected at a follow-up in 2020: cartilage repair tissue quality was evaluated by MRI using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Patient-reported outcome measures (PROMs) included the Oxford Hip Score (OHS) and Core Outcome Measure Index (COMI). Clinical examination included range of motion, impingement tests, and pain. Results: A total of 12 hips from 11 patients were included (ten males, one female, mean age 26.8 years (SD 5.0), mean follow-up 6.2 years (SD 5.2 months)). The mean postoperative MOCART score was 66.3 (SD 16.3). None of the patients required conversion to total hip arthroplasty. Two patients had anterior impingement. External hip rotation was moderately limited in four patients. There was a correlation between MOCART and follow-up time (rs = -0.61; p = 0.035), but not with initial cartilage damage, age, BMI, or imaging time delay before surgery. PROMs improved significantly: OHS from 37.4 to 42.7 (p = 0.014) and COMI from 4.1 to 1.6 (p = 0.025). There was no correlation between MOCART and PROMs. Conclusion: Based on the reported mid-term results, we consider AMIC as an encouraging treatment option for large cartilage lesions of the hip. Nonetheless, the clinical evidence of AMIC in FAI patients remains to be determined, ideally in the context of randomized controlled trials.

Isolating factors for the prediction of rebound after guided growth with tension band plating for the valgus deformity of the knee.

Purpose: The conditions leading to growth rebound after hemiepiphysiodesis are still poorly understood. This article analyzes the radiographical outcomes after guided growth with tension band plating, using plates in idiopathic genu valgum patients and attempts to generate a predictive model of growth rebound. Methods: Patients with idiopathic genu valgum deformity who received tension band plating were selected for evaluation. We only analyzed coronal plane deformities. Only patients with a long-standing X-ray before tension band plating surgery, a long-standing X-ray at tension band plating removal, and a long-standing X-ray at the latest follow-up after tension band plating removal were considered for this study. The change of mechanical axis deviation between the tension band plating removal and the last follow-up was evaluated for rebound, and ordinal logistic regression was performed to determine the relevant variables for predictive modeling rebound growth. Results: Overall, 100 patients (189 legs) were analyzed. The mean mechanical axis deviation at tension band plating removal was 8.4 mm in varus direction, and the mean mechanical axis deviation at the last follow-up was -3.4 mm (p ≤ 0.001). However, 111 legs (59%) showed rebound growth, 57 (30%) stayed stable, and 21 (11%) showed a continuous correction. Six significant factors significantly influencing rebound were isolated which are clinically relevant: sex, age, baseline mechanical axis deviation, mechanical lateral distal femoral angle, and mechanical medial proximal tibial angle, and mechanical axis deviation correction rate. Mechanical axis deviation correction rate had the highest odds ratios. The machine learning classification model for predicting rebound growth built from the study data showed a misclassification rate of 39%. Conclusion: There was a high rate of rebound growth in this cohort, especially for patients at a young age at implantation. The highest risk factors for rebound growth were male sex, and high correction rates, such as found during peak growth spurt. The proposed classification model needs more data to improve its predictive power before it can be used in clinics. Level of evidence: Level III.

Lean Body Mass in Boys With Prader-Willi Syndrome Increases Normally During Spontaneous and Induced Puberty.

CONTEXT: Prader-Labhart-Willi syndrome (PWS) is a rare genetic disorder characterized by intellectual disability, behavioural problems, and hypothalamic dysfunction combined with specific dysmorphisms. In PWS, growth hormone treatment is given primarily to improve body composition, yet lean body mass (LBM) does not normalize. Male hypogonadism is frequent in PWS and becomes evident during puberty. While LBM increases in normal boys during puberty, it is not known whether LBM and muscle mass concomitantly increase in PWS during spontaneous or induced puberty. OBJECTIVE: To describe the peripubertal increment in muscle mass in boys with PWS undergoing growth hormone treatment. DESIGN: Single-center, retrospective descriptive study, using data from 4 years before until 4 years after onset of puberty. SETTING: Primary referral centre for PWS. PATIENTS: Thirteen boys diagnosed with genetically proven PWS. The mean age at onset of puberty was 12.3 years; the mean observation period before (after) onset of puberty was 2.9 (3.1) years. INTERVENTION: Puberty was induced upon pubertal arrest. All boys received internationally standardized growth hormone treatment. MAIN OUTCOME MEASURE: Lean mass index (LMI) determined by dual energy X-ray absorptiometry. RESULTS: LMI increased by 0.28 kg/m2 per year before puberty and by 0.74 kg/m2 per year after the onset of puberty. The time before puberty explained less than 10% of the variation in LMI, whereas the time after puberty onset explained about 25%. CONCLUSION: Boys with PWS showed a recognizable increment in LMI during both spontaneous and induced puberty compared with the prepubertal phase, which was within the trajectories of normal boys. Therefore, timely testosterone substitution in the absence or at arrest of puberty during growth hormone treatment is important to optimize peak LBM in PWS.

Measurement properties of PROMIS short forms for pain and function in patients receiving knee arthroplasty.

BACKGROUND: While there are a few studies on measurement properties of PROMIS short forms for pain and function in patients with knee osteoarthritis, nothing is known about the measurement properties in patients with knee arthroplasty. Therefore, this study examined the measurement properties of the German Patient-Reported Outcomes Measurement Information System (PROMIS) short forms for pain intensity (PAIN), pain interference (PI) and physical function (PF) in knee arthroplasty patients. METHODS: Short forms were collected from consecutive patients of our clinic's knee arthroplasty registry before and 12 months post-surgery. Oxford Knee Score (OKS) was the reference measure. A subsample completed the short forms twice to test reliability. Construct validity and responsiveness were assessed using scale-specific hypothesis testing. For reliability, Cronbach's alpha, intraclass correlation coefficients, and agreement using standard error of measurement (SEMagr) were used. Agreement was used to determine standardised effect sizes and smallest detectable changes (SDC90). Individual-level minimal important change (MIC) was calculated using a method of adjusted prediction. RESULTS: Of 213 eligible patients, 155 received questionnaires, 143 returned baseline questionnaires and 119, 12-month questionnaires. Correlations of short forms with OKS were large (│r│ ≥ 0.7) with slightly lower values for PAIN, and specifically for men. Cronbach's alpha values were ≥ 0.84 and intraclass correlation coefficients ≥ 0.90. SEMagr were around 3.5 for PAIN and PI and 1.7 for PF. SDC90 were around 8 for PAIN and PI and 4 for PF. Follow-up showed a relevant ceiling effect for PF. Correlations with OKS change scores of around 0.5 to 0.6 were moderate. Adjusted MICs were 7.2 for PAIN, 3.5 for PI and 5.7 for PF. CONCLUSION: Our results partly support the use of the investigated short forms for knee arthroplasty patients. The ability of PF to differentiate between patients with high perceived recovery is limited. Therefore, the advantages and disadvantages should be strongly considered within the context of the intended use.

Percutaneous minimal invasive Achilles tendon lengthening improves clinical and radiographic outcomes in severe flexible flatfeet with shortened triceps sureae complex in early childhood: A retrospective study.

BACKGROUND: Severe flexible flatfeet with triceps surae complex shortening are prognostically unfavorable in early childhood and may compromise normal foot development. METHODS: This retrospective, IRB-approved study included 20 children (38 feet) under 6 years with severe flexible flatfeet and triceps surae complex shortening. Treatment included minimally invasive percutaneous achilles tendon lengthening followed by a 4-week cast fixation and corrective orthotic therapy under talo-navicular reposition for at least 6-months. Preoperative weightbearing x-rays and at the last available follow-up included anteroposterior talus-first metatarsal angle and lateral talus pitch, Meary's and talocalcaneal angle and were compared to reference values. ROM, surgeon-rated clinical outcomes and complications/re-interventions were evaluated. RESULTS: Age at surgery was 3.7 years (1.3-5.9 y) and follow-up time was 4.3 years (1.1-8.9 y). No complications occurred. Clinical outcome was good (68 %) to very good (26 %). Ratio of normal angles increased significantly for three angles. Dorsiflexion ROM improved from -5.0 ± 6.8° at baseline to 15.7 ± 7.6°. CONCLUSIONS: With significant improvements in clinical and radiographic outcomes, minimal-invasive percutaneous Achilles tendon lengthening followed by orthotic therapy seems to be a valuable treatment option for selected preschool-aged patients with severe, flexible flatfeet with significantly shortened triceps surae. LEVEL OF EVIDENCE: IV.

Gonadal Hormone Substitution in People with Prader-Labhart-Willi Syndrome: An International Prader-Willi Syndrome Organisation Survey.

BACKGROUND: Prader-Labhart-Willi syndrome (PWS) is a rare genetic disorder characterized by intellectual disability, behavioural problems, hypothalamic dysfunction, and specific dysmorphisms. Hypothalamic dysfunction causes growth hormone deficiency, dysregulation of energy balance, and hypogonadism. Although hypogonadism is prevalent in PWS, there are no clear guidelines for diagnosis and treatment. In particular, gonadal hormone substitution is a matter of debate due to concerns associated with the potentially induced aggressive behaviour, foremost in males, by sex steroids. METHODS: In 2019, a workshop dedicated to hypogonadism was held prior to the 10th International PWS Organization Conference. In this context, we designed a questionnaire to assess "the current standard of care" of hypogonadism in children and adults with PWS, which was sent out to physicians caring for people with PWS worldwide. RESULTS: Responses were received from a total of 24 centres located in 19 countries. Participating centres treat a total number of at least 1,000 children and adults with PWS. Responses showed limited consensus on who should be treated or at what age treatment should commence. Remarkably, very few behavioural problems were attributed to hormone substitution. CONCLUSION: Based on our findings, we make recommendations to progress the knowledge on hypogonadism in PWS and improve daily practice.

Measurement properties of PROMIS short forms for pain and function in total hip arthroplasty patients.

INTRODUCTION: While the Patient-Reported Outcomes Measurement Information System (PROMIS) is mainly designed for computer adaptive testing, its static short forms (SF) are used when a paper-pencil format is preferred or item banks are not yet translated into the target language. This study examined the measurement properties of the German PROMIS-SF for pain intensity (PAIN), pain interference (PI) and physical function (PF) in total hip arthroplasty (THA) patients. METHODS: SF were collected before and 12 months post-surgery. Higher scores indicate more PAIN, higher PI and better PF. Oxford Hip Score (OHS) was the main reference measure. Six months post-surgery, a subsample completed the SF twice within 14 days to test reliability. RESULTS: Of 172 eligible patients, 147 consented to participate and received questionnaires; 132 (74 males) returned baseline questionnaires (mean age 65.8 ± 10.2 years) and 116, 12-month questionnaires. Forty-five patients provided test-retest data. Correlations of all SF with OHS were large (│r│ ≥ 0.7; confidence intervals did not include 0.50). Cronbach's alpha values were: PAIN, 0.86; PI, 0.93; PF, 0.91. Intraclass correlation coefficients were: PAIN, 0.77; PI, 0.81; PF, 0.69. Standard errors of measurement were: PAIN, 3.8; PI, 2.8; PF, 3.6. Smallest detectable change thresholds were: PAIN, 8.8; PI, 6.6; PF, 8.4. Follow-up data showed a ceiling effect (best score) for PAIN (66%), PI (76%), and PF (66%). SF change scores showed large correlations with OHS change scores (│r│ > 0.6). CONCLUSION: Our results provide some evidence of construct validity, and acceptable reliability and responsiveness of PROMIS-SF for pain and function in THA patients. These SF can thus be considered acceptable for use, although patients' improvement in physical function might be underestimated due to the large follow-up PF score ceiling effects.

Measurement qualities of PROMIS instruments are mainly assessed for computer adaptive testing but not for non-adaptive short questionnaires. As these questionnaires are in use, their measurement properties must also be evaluated. Results from computer adaptive testing cannot simply be transferred.We studied the measurement qualities of the German PROMIS short questionnaires for pain intensity, pain interference and physical function in patients undergoing hip replacement. We wanted to see how these questionnaires perform when compared to the Oxford Hip Score, a standard questionnaire commonly used to test hip-related disability in these patients.The three questionnaires can be considered acceptable for use in hip replacement patients, but some limitations do exist. Patient improvement in physical function might be underestimated because many patients reach the highest possible score and further improvements cannot be measured. Also, any small but important improvement in physical function cannot be distinguished from measurement error in individual patients.

The increase in child obesity in Switzerland is mainly due to migration from Southern Europe - a cross-sectional study.

BACKGROUND: Novel height, weight and body mass index (BMI) references for children in Switzerland reveal an increase in BMI compared to former percentile curves. This trend may be the result of children with parents originating from Southern European countries having a higher risk of being overweight compared to their peers with parents of Swiss origin. We examined the association of generational, migration-related and socioeconomic factors on BMI in Switzerland and expect the results to lead to more targeted prevention programs. METHODS: From contemporary cross-sectional data, we calculated subgroup-specific BMI percentiles for origin. Results for children of Swiss origin were compared with historical BMI data from Zurich. We tested for the association of overweight and obesity with origin and compared the distributions of BMI percentile ranks. Logistic regression analyses were applied to predict probabilities of being overweight or obese by origin and the Swiss neighborhood index of socioeconomic position (SSEP). RESULTS: Compared to the BMI from two generations ago, the newly calculated BMI increased only slightly for children with both parents from Switzerland; 1.2% of these girls and 1.6% of these boys are obese. In the Swiss population, 13% of the children have parents from Southern Europe and the proportion of obesity is 57 and 42% in these boys and girls, respectively. Their BMI medians correspond to those of their parents' countries of origin. For the probability of being overweight or obese, the SSEP differences are less important than the status of origin. CONCLUSION: We identified children with both parents from Southern Europe as the main influence driving the increase in BMI in Switzerland over the past 50 years. A differentiated consideration of the proportions of various migrant groups within cross-sectional samples is essential when monitoring BMI. Ignoring fluctuations can lead to false conclusions.

Contemporary height, weight and body mass index references for children aged 0 to adulthood in Switzerland compared to the Prader reference, WHO and neighbouring countries.

Background: In 2011, WHO growth curves replaced those of Prader and colleagues (First Zurich longitudinal study) in Switzerland.Aim: To present contemporary height-, weight- and body mass index (BMI)-for-age references reflecting children's growth in modern Switzerland.Subjects and methods: Cross-sectional sample comprising 30,141 boys and girls aged 0-20 years measured between 2012 and 2019. Height, weight and BMI reference curves were created using the LMS method. Derived percentiles were compared with those of Prader, WHO and neighbouring countries.Results: Growth in the first 5 years is almost identical with Prader curves. Thereafter children are taller, yet their final height is only about 1 cm higher. Today's children, in particular boys, are considerably heavier. In comparison with WHO growth references, Swiss children are taller from the second year until adulthood; the WHO 3rd percentiles lie about 4 cm below those of our updated references. Weight and BMI median percentiles from our sample are similar to those of WHO and higher than the Prader curves. However, the course of the 97th BMI percentile WHO curves extends well below the 97th percentile of the updated Swiss curves.Conclusion: This study provides contemporary reference data for assessing individual growth based on height, weight and BMI of Swiss children.

Measurement properties of PROMIS short forms for pain and function in orthopedic foot and ankle surgery patients.

PURPOSE: To examine the measurement properties of the German PROMIS short forms for pain intensity (PAIN), pain interference (PI) and physical function (PF) in orthopedic foot and ankle surgery patients. METHODS: Patient-rated outcomes were collected from consecutive patients of our foot and ankle registry before and 6 months after surgery. Measurement properties were tested according to the COnsensus-based Standards for the selection of health status Measurement Instruments (COSMIN). The German Foot Function Index (FFI-D) served as a legacy measure. RESULTS: 748 patients were included in our cross-sectional sample. Longitudinal and test-retest data were available for 202 and 65 patients, respectively. Construct validity of all short forms was good. All Cronbach's α and intraclass correlation coefficients were > 0.7. The smallest detectable change (SDC) was highest for PF (8.9) and lowest for PI (6.5). Minimal important change was 4 to 5 points and thus smaller than SDC for all instruments. We observed a baseline ceiling effect for PF. PI showed insufficiently correlated change scores with FFI-D disability change scores, and therefore failed the responsiveness testing. CONCLUSION: Our study showed some adequate psychometric properties, but also certain aspects regarding interpretability and responsiveness that researchers must be aware of when using PROMIS short forms of pain and function in foot and ankle surgery patients.