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Dive into the research topics where Melinda M. Witbreuk is active.

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Featured researches published by Melinda M. Witbreuk.


Journal of Children's Orthopaedics | 2009

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

Melinda M. Witbreuk; M. Bolkenbaas; M. G. Mullender; I. N. Sierevelt; Philip P. Besselaar

PurposePatients with moderate and severe slipped capital femoral epiphysis (SCFE) develop osteoarthritis earlier in life in association with mechanical impingement.MethodsTo 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.ResultsThe 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.ConclusionsBased 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.


Journal of Bone and Joint Surgery-british Volume | 2009

Prolonged treatment with the Pavlik harness in infants with developmental dysplasia of the hip

J. A. van der Sluijs; L. De Gier; J. I. Verbeke; Melinda M. Witbreuk; J. E. H. Pruys; B.J. van Royen

We prospectively studied the benefits and risks of prolonged treatment with the Pavlik harness in infants with idiopathic developmental dysplasia of the hip. Bracing was continued as long as abduction improved. It was started at a mean age of four months (1 to 6.9). Outcome measures were the number of successful reductions, the time to reduction, the acetabular index and evidence of avascular necrosis at follow-up at one year. In 50 infants with 62 subluxated and dislocated hips (42 Graf type III and 20 type IV), 37 were reduced successfully with a mean time to reduction of 13.4 weeks (sd 6.8). Bracing was successful in 31 type-III (73.8%) and in only six type-IV hips (20%, p = 0.002). Avascular necrosis was seen in ten hips. Prolonged treatment with the Pavlik harness for developmental dysplasia of the hip over the age of one month can be beneficial in type-III hips, but it is unclear as to whether this is the optimal treatment, since it may postpone the need for closed or open reduction to a more unfavourable age. The use of the Pavlik harness in type-IV hips in this age group is questionable, but if used, prolonged bracing is not advised.


Journal of Children's Orthopaedics | 2013

Slipped capital femoral epiphysis and its association with endocrine, metabolic and chronic diseases: a systematic review of the literature

Melinda M. Witbreuk; F. J. van Kemenade; J. A. van der Sluijs; Elise P. Jansma; J. Rotteveel; B.J. van Royen

PurposePuberty, obesity, endocrine and chronic systemic diseases are known to be associated with slipped capital femoral epiphysis (SCFE). The mechanical insufficiency of the physis in SCFE is thought to be the result of an abnormal weakening of the physis. However, the mechanism at the cellular level has not been unravelled up to now.MethodsTo understand the pathophysiology of endocrine and metabolic factors acting on the physis, we performed a systematic review focussing on published studies reporting on hormonal, morphological and cellular abnormalities of the physis in children with SCFE. In addition, we looked for studies of the effects of endocrinopathies on the human physis which can lead to cause SCFE and focussed in detail on hormonal signalling, hormone receptor expression and extracellular matrix (ECM) composition of the physis. We searched in the PubMed, EMBASE.com and The Cochrane Library (via Wiley) databases from inception to 11th September 2012. The search generated a total of 689 references: 382 in PubMed, 232 in EMBASE.com and 75 in The Cochrane Library. After removing duplicate papers, 525 papers remained. Of these, 119 were selected based on titles and abstracts. After excluding 63 papers not related to the human physis, 56 papers were included in this review.ResultsActivation of the gonadal axis and the subsequent augmentation of the activity of the growth hormone–insulin-like growth factor 1 (GH-IGF-1) axis are important for the pubertal growth spurt, as well as for cessation of the physis at the end of puberty. The effects of leptin, thyroid hormone and corticosteroids on linear growth and on the physis are also discussed. Children with chronic diseases suffer from inflammation, acidosis and malnutrition. These consequences of chronic diseases affect the GH-IGF-1 axis, thereby, increasing the risk of the development of SCFE. The risk of SCFE and avascular necrosis in children with chronic renal insufficiency, growth hormone treatment and renal osteodystrophy remains equivocal.ConclusionsSCFE is most likely the result of a multi-factorial event during adolescence when height and weight increase dramatically and the delicate balance between the various hormonal equilibria can be disturbed. Up to now, there are no screening or diagnostic tests available to predict patients at risk.


Acta Orthopaedica | 2015

Malunion of distal radius fractures in children Remodeling speed in 33 children with angular malunions of >= 15 degrees

Kimberly T V Jeroense; Tim America; Melinda M. Witbreuk; Johannes A. van der Sluijs

Background and purpose — Distal forearm fractures in children have excellent remodeling potential. The current literature states that 15° is the maximum acceptable angulation limit, though studies focusing on remodeling capacity above this value are lacking. We present data on the remodeling process in children with distal radius malunions with an angulation of ≥ 15°. Patients and methods — Retrospectively, we radiographically evaluated the remodeling in 33 children (aged 3–14 years) with 40 distal radius fractures healed in ≥ 15° angulation in the dorsovolar (DV) plane (n = 32) and/or the radioulnar (RU) plane (n = 8). Malunion angulation at the start and at last follow-up was measured on AP and lateral-view radiographs. Mean follow-up time was 9 (3–29) months. Results — All fractures showed remodeling. Mean DV malunion angulation was 23° (15–49) and mean RU malunion angulation was 21° (15–33). At follow-up, this had remodeled to mean 8° (–2 to 21) DV and 10° (3–17) RU. Mean remodeling speed (RS) was 2.5° (0.4–7.6) per month. There was a negative correlation between RS and remodeling time (RT) and a positive correlation between RS and malunion angulation. The relationship between RS and RT was exponential. RS was not found to be related to age or sex. Interpretation — Remodeling speed decreases exponentially over time. Its starting value depends on the amount of angulation of distal radius fractures. This compensates for the increased need for remodeling in severely angulated fractures.


PLOS ONE | 2016

Knee Moment-Angle Characteristics and Semitendinosus Muscle Morphology in Children with Spastic Paresis Selected for Medial Hamstring Lengthening

Helga Haberfehlner; Richard T. Jaspers; Erich Rutz; Jules G. Becher; Jaap Harlaar; Johannes A. van der Sluijs; Melinda M. Witbreuk; Jacqueline Romkes; Marie Freslier; Reinald Brunner; Huub Maas; Annemieke I. Buizer

To increase knee range of motion and improve gait in children with spastic paresis (SP), the semitendinosus muscle (ST) amongst other hamstring muscles is frequently lengthened by surgery, but with variable success. Little is known about how the pre-surgical mechanical and morphological characteristics of ST muscle differ between children with SP and typically developing children (TD). The aims of this study were to assess (1) how knee moment-angle characteristics and ST morphology in children with SP selected for medial hamstring lengthening differ from TD children, as well as (2) how knee moment-angle characteristics and ST morphology are related. In nine SP and nine TD children, passive knee moment-angle characteristics and morphology of ST (i.e. fascicle length, muscle belly length, tendon length, physiological cross-sectional area, and volume) were assessed by hand-held dynamometry and freehand 3D ultrasound, respectively. At net knee flexion moments above 0.5 Nm, more flexed knee angles were found for SP compared to TD children. The measured knee angle range between 0 and 4 Nm was 30% smaller in children with SP. Muscle volume, physiological cross-sectional area, and fascicle length normalized to femur length were smaller in SP compared to TD children (62%, 48%, and 18%, respectively). Sixty percent of the variation in knee angles at 4 Nm net knee moment was explained by ST fascicle length. Altered knee moment-angle characteristics indicate an increased ST stiffness in SP children. Morphological observations indicate that in SP children planned for medial hamstring lengthening, the longitudinal and cross-sectional growth of ST muscle fibers is reduced. The reduced fascicle length can partly explain the increased ST stiffness and, hence, a more flexed knee joint in these SP children.


Journal of Bone and Joint Surgery-british Volume | 2015

The head-shaft angle of the hip in early childhood: a comparison of reference values for children with cerebral palsy and normally developing hips.

J. van der List; Melinda M. Witbreuk; Annemieke I. Buizer; J. A. van der Sluijs

The recognition of hips at risk of displacement in children with cerebral palsy (CP) is a difficult problem for the orthopaedic surgeon. The Gross Motor Function Classification System (GMFCS) and head-shaft angle (HSA) are prognostic factors for hip displacement. However, reference values for HSA are lacking. This study describes and compares the development of HSA in normal hips and children with CP. We selected 33 children from a retrospective cohort with unilateral developmental dysplasia of the hip (DDH) (five boys, 28 girls) and 50 children (35 boys, 15 girls) with CP with GMFCS levels II to V. HSA of normal developing hips was measured at the contralateral hip of unilateral DDH children (33 hips) and HSA of CP children was measured in both hips (100 hips). Measurements were taken from the radiographs of the children at age two, four and seven years. The normal hip HSA decreased by 2° per year (p < 0.001). In children with CP with GMFCS levels II and III HSA decreased by 0.6° (p = 0.046) and 0.9° (p = 0.049) per year, respectively. The HSA did not alter significantly in GMFCS levels IV and V. Between the ages of two and eight years, the HSA decreases in normal hips and CP children with GMFCS level, II to III but does not change in GMFCS levels IV to V. As HSA has a prognostic value for hip displacement, these reference values may help the orthopaedic surgeon to predict future hip displacement in children with CP.


Journal of Pediatric Orthopaedics B | 2013

Retrospective radiographic evaluation of treatment results of developmental dysplasia of the hip in walking-age children

Nicole A. M. Heesakkers; Melinda M. Witbreuk; Philip P. Besselaar; Johannes A. van der Sluijs

We evaluated treatment results of 22 children (32 hips) with idiopathic hip dislocation after walking age in two Dutch academic hospitals. The Tönnis classification was used preoperatively. Outcome was measured using the Severin and Kalamchi classification. The mean age at treatment was 24 months and the mean follow-up was 6.8 years. In 24 hips (73%), a perfect outcome was found (Kalamchi score⩽1 and Severin score of 1). A fair or a poor outcome according to Severin (≥3) was found in five hips (15%). Treatment of a hip dislocation beyond 18 months of age usually results in adequate hip development with limited avascular necrosis. Level of evidence: Level III.


Human Movement Science | 2017

Analysis of gait patterns pre- and post- Single Event Multilevel Surgery in children with Cerebral Palsy by means of Offset-Wise Movement Analysis Profile and Linear Fit Method

Andrea Ancillao; Marjolein M. van der Krogt; Annemieke I. Buizer; Melinda M. Witbreuk; Paolo Cappa; Jaap Harlaar

Gait analysis is used for the assessment of walking ability of children with cerebral palsy (CP), to inform clinical decision making and to quantify changes after treatment. To simplify gait analysis interpretation and to quantify deviations from normality, some quantitative synthetic descriptors were developed over the years, such as the Movement Analysis Profile (MAP) and the Linear Fit Method (LFM), but their interpretation is not always straightforward. The aims of this work were to: (i) study gait changes, by means of synthetic descriptors, in children with CP that underwent Single Event Multilevel Surgery; (ii) compare the MAP and the LFM on these patients; (iii) design a new index that may overcome the limitations of the previous methods, i.e. the lack of information about the direction of deviation or its source. Gait analysis exams of 10 children with CP, pre- and post-surgery, were collected and MAP and LFM were computed. A new index was designed asa modified version of the MAP by separating out changes in offset (named OC-MAP). MAP documented an improvement in the gait pattern after surgery. The highest effect was observed for the knee flexion/extension angle. However, a worsening was observed as an increase in anterior pelvic tilt. An important source of gait deviation was recognized in the offset between observed tracks and reference. OC-MAP allowed the assessment of the offset component versus the shape component of deviation. LFM provided results similar to OC-MAP offset analysis but could not be considered reliable due to intrinsic limitations. As offset in gait features played an important role in gait deviation, OC-MAP synthetic analysis was proposed as a novel approach to a meaningful parameterisation of global deviations in gait patterns of subjects with CP and gait changes after treatment.


PLOS ONE | 2018

Outcome of medial hamstring lengthening in children with spastic paresis: A biomechanical and morphological observational study

Helga Haberfehlner; Richard T. Jaspers; Erich Rutz; Jaap Harlaar; Johannes A. van der Sluijs; Melinda M. Witbreuk; Kim van Hutten; Jacqueline Romkes; Marie Freslier; Reinald Brunner; Jules G. Becher; Huub Maas; Annemieke I. Buizer

To improve gait in children with spastic paresis due to cerebral palsy or hereditary spastic paresis, the semitendinosus muscle is frequently lengthened amongst other medial hamstring muscles by orthopaedic surgery. Side effects on gait due to weakening of the hamstring muscles and overcorrections have been reported. How these side effects relate to semitendinosus morphology is unknown. This study assessed the effects of bilateral medial hamstring lengthening as part of single-event multilevel surgery (SEMLS) on (1) knee joint mechanics (2) semitendinosus muscle morphology and (3) gait kinematics. All variables were assessed for the right side only. Six children with spastic paresis selected for surgery to counteract limited knee range of motion were measured before and about a year after surgery. After surgery, in most subjects popliteal angle decreased and knee moment-angle curves were shifted towards a more extended knee joint, semitendinosus muscle belly length was approximately 30% decreased, while at all assessed knee angles tendon length was increased by about 80%. In the majority of children muscle volume of the semitendinosus muscle decreased substantially suggesting a reduction of physiological cross-sectional area. Gait kinematics showed more knee extension during stance (mean change ± standard deviation: 34±13°), but also increased pelvic anterior tilt (mean change ± standard deviation: 23±5°). In most subjects, surgical lengthening of semitendinosus tendon contributed to more extended knee joint angle during static measurements as well as during gait, whereas extensibility of semitendinosus muscle belly was decreased. Post-surgical treatment to maintain muscle belly length and physiological cross-sectional area may improve treatment outcome of medial hamstring lengthening.


Journal of Children's Orthopaedics | 2015

The prognostic value of the head-shaft angle on hip displacement in children with cerebral palsy

J. P. J. van der List; Melinda M. Witbreuk; Annemieke I. Buizer; J. A. van der Sluijs

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J. A. van der Sluijs

VU University Medical Center

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Annemieke I. Buizer

VU University Medical Center

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B.J. van Royen

VU University Medical Center

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Jaap Harlaar

VU University Medical Center

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F. J. van Kemenade

VU University Medical Center

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Huub Maas

VU University Amsterdam

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Jules G. Becher

VU University Medical Center

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