Thomas Dreher

Different culture media affect growth characteristics, surface marker distribution and chondrogenic differentiation of human bone marrow-derived mesenchymal stromal cells

BackgroundBone marrow-derived mesenchymal stromal cells (BM-MSCs) play an important role in modern tissue engineering, while distinct variations of culture media compositions and supplements have been reported. Because MSCs are heterogeneous regarding their regenerative potential and their surface markers, these parameters were compared in four widely used culture media compositions.MethodsMSCs were isolated from bone marrow and expanded in four established cell culture media. MSC yield/1000 MNCs, passage time and growth index were observed. In P4, typical MSC surface markers were analysed by fluorescence cytometry. Additionally, chondrogenic, adipogenic and osteogenic differentiation potential were evaluated.ResultsGrowth index and P0 cell yield varied importantly between the media. The different expansion media had a significant influence on the expression of CD10, CD90, CD105, CD140b CD146 and STRO-1. While no significant differences were observed regarding osteogenic and adipogenic differentiation, chondrogenic differentiation was superior in medium A as reflected by GAG/DNA content.ConclusionsThe choice of expansion medium can have a significant influence on growth, differentiation potential and surface marker expression of mesenchymal stromal cells, which is of fundamental importance for tissue engineering procedures.

FGF-2 addition during expansion of human bone marrow-derived stromal cells alters MSC surface marker distribution and chondrogenic differentiation potential.

Although clinical applications using mesenchymal stromal cells (MSCs) are becoming more frequent, procedures for their in vitro culture are far from standardized. Growth factors such as FGF‐2 are frequently added during expansion to improve population growth and differentiation characteristics. However, up to now its influence on surface marker distribution of MSCs has been close to unknown. The purpose of this study was therefore to analyse effects of FGF‐2 supplementation on pre‐selection of MSC subpopulations.

Motion analysis of the upper extremity in children with unilateral cerebral palsy—An assessment of six daily tasks

Restrictions in range of motion of the upper extremity are common in patients with unilateral cerebral palsy (CP). The purpose of this study was to investigate movement deviations of the upper extremity in children with unilateral CP by means of 3D motion capture as well as by the use of easy to use scores and questionnaires (MACS, MRC, MAS, ABILHAND-Kids). 16 children with a spastic, unilateral CP were included and compared to a group of 17 typically developing adolescents (TD). The movement time and range of motion (ROM) of six uni- and bimanual daily tasks were compared and correlated with the scores and questionnaires. Movement times increased significantly with involvement according to MACS in all tasks. The restrictions in ROM were pronounced in the forearm. As a compensatory mechanism the children of the MACS 2 and 3 groups showed increased trunk movement. Furthermore, there was a positive correlation between the MACS and the ABILHAND-Kids Questionnaire. In contrast to previous studies, which reported a correlation between the restrictions in ROM and the MACS, this study showed no consistent correlation between the restrictions in ROM neither with the MACS nor with the ABILHAND-Kids. While the MACS and the ABILHAND-Kids function as a simple rating tool for clinical use, the detailed analysis of different daily tasks using 3-D-motion capture provides more detailed information about the movement deviations and spatiotemporal parameters.

Factors associated with recurrence after femoral derotation osteotomy in cerebral palsy

Femoral derotation osteotomy (FDO) as gold standard treatment for internal rotation gait in cerebral palsy (CP) leads to satisfying short-term results, whereas rates of recurrence up to 33% are reported in long-term outcome studies. The purpose of this study was therefore to identify factors contributing to recurrence of internal rotation gait in patients with CP who were treated with FDO in childhood. 70 patients (age: 10 (± 3.3) years at surgery) with bilateral CP and internal rotation gait were examined pre-, one year and at least five years (mean 8 ± 2 years) postoperatively after distal or proximal FDO, using standardized clinical examination and 3D gait-analysis. 27 patients had a good hip rotation one year postoperatively (between 5° external and 15° internal for both limbs) and were considered for the analysis of factors contributing to recurrence of internal rotation gait. Regarding all included patients both mean hip rotation and foot progression angle improved significantly (p < 0.001) from pre- to postoperative. A significant deterioration in hip rotation (more involved side) (p < 0.001) from one year postoperatively to the long-term follow-up can be observed. Younger age, reduced hip joint impulse, increased plantar flexion and internal foot progression angle postoperatively could be identified as factors for recurrence. FDO on average leads to a satisfactory correction of internal rotation gait. In order to improve the long-term outcome after FDO the time of multilevel surgery should be indicated as late as possible and the different factors leading to potential recurrence should be considered.

Fluorescence activated enrichment of CD146+ cells during expansion of human bone-marrow derived mesenchymal stromal cells augments proliferation and GAG/DNA content in chondrogenic media

BackgroundWhile numerous subpopulations of BM-MSCs have been identified, the relevance of these findings regarding the functional properties remains mostly unclear. With regards to attempts of enhancing differentiation results by preselecting certain MSC subtypes, we have evaluated the efficiency of CD146 purification during expansion, and evaluated whether these measures enhanced MSC differentiation results.MethodsHuman MSCs were derived from bone marrow of six donors and cultured in two different culture media. After P1, MSCs were purified by either magnetic or fluorescence sorting for CD146, with unsorted cells as controls. Growth characteristics and typical MSC surface markers were assessed from P0 to P3. After P3, chondrogenic, osteogenic and adipogenic differentiation potential were assessed.ResultsDespite a high variability of CD146 expression among the donors, fluorescence sorting significantly increased the number of CD146+ cells compared to control MSCs, while magnetic sorting led to a lesser enrichment. Osteogenic and adipogenic differentiation potential was not affected by the sorting process. However, FACS-sorted cells showed significantly increased GAG/DNA content after chondrogenic differentiation compared to control MSCs.ConclusionFACS sorting of CD146+ cells was more efficient than magnetic sorting. The underlying mechanism of increased GAG/DNA content after enrichment during expansion remains unclear, but may be linked to increased proliferation rates in these cells.

The effects of muscle-tendon surgery on dynamic electromyographic patterns and muscle tone in children with cerebral palsy

During multilevel surgery, muscle-tendon lengthening (MTL) is commonly carried out in children with cerebral palsy. However, it is unclear if MTL also modifies increased muscle tone and if pathologic activation patterns are changed as an indirect effect of the biomechanical changes. Since investigations addressing this issue are limited, this study aimed at evaluating the effects of MTL on muscle tone and activation pattern. Forty-two children with spastic diplegia who were treated by MTL underwent standardized muscle tone testing (modified Ashworth and Tardieu test), dynamic EMG and three-dimensional gait analysis before, one and three years after MTL. For the evaluation of muscle activation patterns the norm-distance of dynamic EMG data was analyzed. Range of motion and joint alignment in clinical examination were found to be significantly improved one year after MTL. However, deterioration of these parameters was noted after three years. Muscle tone was significantly reduced one year postoperatively but showed an increase after three years. Joint kinematics were found significantly closer to reference data of age matched controls initially after surgery, but deteriorated until three years postoperatively. However, the EMG patterns of the muscles which were surgically addressed were found to be unchanged in either follow-up. These findings suggest that despite the influence of MTS on biomechanics and physiology (muscle tone reduction and improvements of joint mobility and gait pattern) MTS does not change abnormal patterns of muscle activation. Recurrence of increased muscle tone and deterioration of kinematic parameters three years after surgery may be attributed to these persistent pathologic activation patterns.

Hip-joint congruity after Dega osteotomy in patients with cerebral palsy: long-term results.

IntroductionNeurogenic hip dislocation is quite common in children with cerebral palsy (CP). The purpose of this study was to evaluate the long-term outcome of single-event multilevel surgery (SEMLS) in combination with hip reconstruction by using a periacetabular osteotomy as described by Dega concerning post-operative remodeling and plasticity of the femoral head post-operatively.MethodsA total of 72 patients with CP as the primary disease and in whom a complex surgical hip reconstruction was performed during SEMLS between 1998 and 2004 were included in the study. There were 45 men and 27 women, with a median age of 7.6 (4.7–16.3) years at the time SEMLS was performed. The mean follow-up time was 7.7xa0years (4.9–11.8). X-rays were taken before and after surgery, and Rippstein 1 and 2 were used for follow-up. As the most reliable value for decentration, migration percentage (MP) as described by Reimers was used. To measure hip-joint cover at follow-up, the centre-edge angle was used. The hip was divided into four different categories according to sphericity and congruity. Using this approach, we could evaluate joint remodeling.ResultsPre-operatively, the mean MP measured by X-ray was 68xa0%. Directly after surgery, this value decreased on average by 12xa0% and at the long-term follow-up was 16.0xa0% on average. A high rate of incongruence was observed on X-rays taken directly after surgery: 66 hip joints were classified as incongruent. The number of aspherical and incongruent joints decreased to 54 at the follow-up examination.ConclusionData of our study with high plasticity of the hip joint suggest that even if the femoral head is deformed and a persistent incongruency after surgery is expected, hip reconstruction can be recommended.

Motion patterns in activities of daily living: 3- year longitudinal follow-up after total shoulder arthroplasty using an optical 3D motion analysis system

BackgroundTotal shoulder arthroplasty (TSA) can improve function in osteoarthritic shoulders, but the ability to perform activities of daily living (ADLs) can still remain impaired. Routinely, shoulder surgeons measure range of motion (ROM) using a goniometer. Objective data are limited, however, concerning functional three-dimensional changes in ROM in ADLs after TSA in patients with degenerative glenohumeral osteoarthritis.MethodsThis study included ten consecutive patients, who received TSA for primary glenohumeral osteoarthritis. The patients were examined the day before, 6 months, and 3 years after shoulder replacement as well. We compared them with a control group (n = 10) without any shoulder pathology and measured shoulder movement by 3D motion analysis using a novel 3 D model. The measurement included static maximum values, the ability to perform and the ROM of the ADLs “combing the hair”, “washing the opposite armpit”, “tying an apron”, and “taking a book from a shelf”.ResultsSix months after surgery, almost all TSA patients were able to perform the four ADLs (3 out of 40 tasks could not be performed by the 10 patients); 3 years postoperatively all patients were able to carry out all ADLs (40 out of 40 tasks possible). In performing the ADLs, comparison of the pre- with the 6-month and 3-year postoperative status of the TSA group showed that the subjects did not fully use the available maximum flexion/extension ROM in performing the four ADLs. The ROM used for flexion/extension did not change significantly (preoperatively 135°-0° -34° vs. 3 years postoperatively 131° -0° -53°). For abduction/adduction, ROM improved significantly from 33°-0° -27° preoperatively to 76° -0° -35° postoperatively. Compared to the controls (118°) the TSA group used less ROM for abduction to perform the four ADLs 3 years postoperatively.ConclusionTSA improves the ability to perform ADL and the individual ROM in ADLs in patients with degenerative glenohumeral osteoarthritis over the course of 3xa0years. However, TSA patients do not use their maximum available abduction ROM in performing ADLs. This is not related to limitations in active ROM, but rather may be caused by pathologic motion patterns, impaired proprioception or both.

Long‐term development of gait after multilevel surgery in children with cerebral palsy: a multicentre cohort study

We investigated the long‐term efficacy and safety of multilevel surgery (MLS) in ambulatory children with bilateral spastic cerebral palsy (CP).

3D motion capture using the HUX model for monitoring functional changes with arthroplasty in patients with degenerative osteoarthritis.

BACKGROUNDnAlthough shoulder hemiarthroplasty (SHA) can improve function in osteoarthritic shoulders, the ability to perform activities of daily living (ADL) may remain impaired. Shoulder surgeons routinely measure parameters such as range of motion, pain, satisfaction and strength. A common subjective assessment of ADL is part of the Constant Score (CS). However, there is limited objective evidence on whether or not shoulder hemiarthroplasty can restore normal range of motion (ROM) in ADL.nnnMETHODSnThe study included eight consecutive patients (n=8; seven women, one man), who underwent SHA for glenohumeral osteoarthritis. The patients were examined the day before, as well as 6 months and 3 years after shoulder replacement. They were compared with a control group with no shoulder pathology, and shoulder movement was measured with 3D motion analysis using the Heidelberg Upper Extremity (HUX) model. Measurements included static maximum values and four ADL.nnnRESULTSnComparing the preoperative to the 3-year postoperative static maximum values, there were significant improvements for abduction from 50.5° (SD ± 3 2.4°) to 72.4° (SD ± 38.2°; p=0.031), for adduction from 6.2° (SD ± 7.7°) to 66.7° (SD ± 18.0°; p=0.008), for external rotation from 15.1° (SD ± 27.9°) to 50.9° (SD ± 27.3°; p=0.031), and for internal rotation from -0.6° (SD ± 3.9°) to 35.8° (SD ± 28.2°; p=0.031). There was a trend of improvement for flexion from 105.8° (SD ± 45.7°) to 161.9° (SD ± 78.2°; p=0.094) and for extension from 20.6° (SD ± 17.0°) to 28.0° (SD ± 12.5°; p=0.313). The comparison of the 3-year postoperative ROM between the SHA group and controls showed significant differences in abduction; 3-year postoperative SHA ROM 72.4° (SD ± 38.2°) vs. 113.5° (SD ± 29.7°) among controls (p=0.029). There were no significant differences compared to the control group in adduction, flexion/extension and rotation 3 years after SHA surgery. In performing the ADL, the pre- to the 6-month and 3-year postoperative status of the SHA group resulted in a significant increase in ROM in all planes (p<0.05). Comparing the preoperative to the 3-year postoperative ROM used in ADL, there was an improvement in the flexion/extension plane, showing an improvement trend from preoperative 85°-0°-25° to postoperative 127°-0°-38° (p=0.063). In comparison, controls used a significantly greater ROM during ADL with mean flexion/extension of 139°-0°-63° (p=0.028). For the abduction/adduction plane, ROM improved significantly from preoperative 25°-0°-19° to postoperative 78°-0°-60° (p=0.031). In comparison to controls with abduction/adduction of 118°-0°-37° 3 years postoperative, the SHA group also used significantly less ROM in the abduction/adduction plane (p=0.028).nnnCONCLUSIONnWhile SHA improves ROM in ADL in patients with degenerative glenohumeral osteoarthritis, it does not restore the full ROM available for performing ADL compared to controls. 3D motion analysis with the HUX model is an appropriate measurement system to detect surgery-related changes in shoulder arthroplasty.