Bastian Marquass

Repair of Chronic Osteochondral Defects Using Predifferentiated Mesenchymal Stem Cells in an Ovine Model

Background: The use of mesenchymal stem cells (MSCs) to treat osteochondral defects caused by sports injuries or disease is of particular interest. However, there is a lack of studies in large-animal models examining the benefits of chondrogenic predifferentiation in vitro for repair of chronic osteochondral defects. Hypothesis: Chondrogenic in vitro predifferentiation of autologous MSCs embedded in a collagen I hydrogel currently in clinical trial use for matrix-associated autologous chondrocyte transplantation facilitates the regeneration of a chronic osteochondral defect in an ovine stifle joint. Study Design: Controlled laboratory study. Methods: The optimal predifferentiation period of ovine MSCs within the type I collagen hydrogel in vitro was defined by assessment of several cellular and molecular biological parameters. For the animal study, osteochondral lesions (diameter 7 mm) were created at the medial femoral condyles of the hind legs in 10 merino sheep. To achieve a chronic defect model, implantation of the ovine MSCs/hydrogel constructs was not performed until 6 weeks after defect creation. The 40 defects were divided into 4 treatment groups: (1) chondrogenically predifferentiated ovine MSC/hydrogel constructs (preMSC-gels), (2) undifferentiated ovine MSC/hydrogel constructs (unMSC-gels), (3) cell-free collagen hydrogels (CF-gels), and (4) untreated controls (UCs). Evaluation followed after 6 months. Results: With regard to proteoglycan content, cell count, gel contraction, apoptosis, compressive properties, and progress of chondrogenic differentiation, a differentiation period of 14 days in vitro was considered optimal. After 6 months in vivo, the defects treated with preMSC-gels showed significantly better histologic scores with morphologic characteristics of hyaline cartilage such as columnarization and presence of collagen type II. Conclusion: Matrix-associated autologous chondrocyte transplantation with predifferentiated MSCs may be a promising approach for repair of focal, chronic osteochondral defects. Clinical Relevance: The results suggest an encouraging method for future treatment of focal osteochondral defects to prevent progression to osteoarthritis.

Matrix-Associated Implantation of Predifferentiated Mesenchymal Stem Cells Versus Articular Chondrocytes: In Vivo Results of Cartilage Repair After 1 Year

Background: The use of predifferentiated mesenchymal stem cells (MSC) leads to better histological results compared with undifferentiated MSC in sheep. This raises the need for a longer term follow-up study and comparison with a clinically established method. Hypothesis: We hypothesized that chondrogenic in vitro predifferentiation of autologous MSC embedded in a collagen I hydrogel leads to better structural repair of a chronic osteochondral defect in an ovine stifle joint after 1 year. We further hypothesized that resulting histological results would be comparable with those of chondrocyte-seeded matrix-associated autologous chondrocyte transplantation (MACT). Study Design: Controlled laboratory study. Methods: Predifferentiation period of ovine MSC within collagen gel in vitro was defined by assessment of several cellular and molecular biological parameters. For the animal study, 2 osteochondral lesions (7-mm diameter) were created at the medial femoral condyles of the hind legs in 9 sheep. Implantation of MSC gels was performed 6 weeks after defect creation. Thirty-six defects were divided into 4 treatment groups: (1) chondrogenically predifferentiated MSC gels (pre-MSC gels), (2) undifferentiated MSC gels (un-MSC gels), (3) MACT gels, and (4) untreated controls (UC). Histological, immunohistochemical, and radiological evaluations followed after 12 months. Results: After 12 months in vivo, pre-MSC gels showed significantly better histological outcome compared with un-MSC gels and UC. Compared with MACT gels, the overall scores were higher for O’Driscoll and International Cartilage Repair Society (ICRS). The repair tissue of the pre-MSC group showed immunohistochemical detection of interzonal collagen type II staining. Radiological evaluation supported superior bonding of pre-MSC gels to perilesional native cartilage. Compared with previous work by our group, no degradation of the repair tissue between 6 and 12 months in vivo, particularly in pre-MSC gels, was observed. Conclusion: Repair of chronic osteochondral defects with collagen hydrogels composed of chondrogenically predifferentiated MSC shows no signs of degradation after 1 year in vivo. In addition, pre-MSC gels lead to partially superior histological results compared with articular chondrocytes. Clinical Relevance: The results suggest an encouraging method for future treatment of focal osteochondral defects without donor site morbidity by harvesting articular chondrocytes.

Knotless anatomic double-layer double-row rotator cuff repair: a novel technique re-establishing footprint and shape of full-thickness tears

The standard technique for restoring footprint after full-thickness tears of the rotator cuff includes double-row or transosseous-equivalent techniques. However, the anatomically typical bird’s beak shape and profile of tendon insertion may not be originally restored and biomechanics may be altered. In this report, the authors describe a technique that involves creating two intratendinous stitches at different levels of the torn tendon. The first passes through the bursal-side layer, the second stitch through the joint-side layer. Both stitches may be performed in mattress suture configuration. The anchorage is performed by knotless anchors in order to avoid knots lying within the insertion area. The footprint is restored first medially then laterally by the use of double-row principles. The joint-side suture is anchored within the medially placed anchor. The bursal-side suture is anchored by a laterally placed anchor. The anatomic insertion and restoration of the shape and profile may be enabled by the described double-layer suture technique. Using a double-layer double-row repair may potentially improve functional results of rotator cuff repair constructs.

Biomechanical Evaluation of Knotless Anatomical Double-Layer Double-Row Rotator Cuff Repair: A Comparative Ex Vivo Study

Background The layered configuration of the rotator cuff tendon is not taken into account in classic rotator cuff tendon repair techniques. Hypothesis The mechanical properties of (1) the classic double-row technique, (2) a double-layer double-row (DLDR) technique in simple suture configuration, and (3) a DLDR technique in mattress suture configuration are significantly different. Study Design Controlled laboratory study. Methods Twenty-four sheep shoulders were assigned to 3 repair groups of full-thickness infraspinatus tears: group 1, traditional double-row repair; group 2, DLDR anchor repair with simple suture configuration; and group 3, DLDR knotless repair with mattress suture configuration. After ultrasound evaluation of the repair, each specimen was cyclically loaded with 10 to 100 N for 50 cycles. Each specimen was then loaded to failure at a rate of 1 mm/s. Results There were no statistically significant differences among the 3 testing groups for the mean footprint area. The cyclic loading test revealed no significant difference among the 3 groups with regard to elongation. For the load-to-failure test, groups 2 and 3 showed no differences in ultimate tensile load when compared with group 1. However, when compared to group 2, group 3 was found to have significantly higher values regarding ultimate load, ultimate elongation, and energy absorbed. Conclusion The DLDR fixation techniques may provide strength of initial repair comparable with that of commonly used double-row techniques. When compared with the knotless technique with mattress sutures, simple suture configuration of DLDR repair may be too weak. Knotless DLDR rotator cuff repair may (1) restore the footprint by the use of double-row principles and (2) enable restoration of the shape and profile. Clinical Relevance Double-layer double-row fixation in mattress suture configuration has initial fixation strength comparable with that of the classic double-row fixation and so may potentially improve functional results of rotator cuff repair.

Saisonale Verteilung von Diagnosen und DRG in der Unfallchirurgie

ZusammenfassungHintergrundDurch die Erfassung von „diagnosis related groups“ (DRG) und Diagnosen lässt sich deren Verteilung im Jahresverlauf ableiten. Ein gehäuftes Auftreten von Erkrankungen zu bestimmten Zeiten kann so identifiziert werden.Patienten und MethodeFür die Zeit von 2004–2010 erfassten wir 22.293 Hauptdiagnosen und DRG an der unfallchirurgischen Klinik. Verletzungen mit gleicher Lokalisation und Behandlung wurden zusammengefasst.ErgebnisseDie häufigsten Verletzungen waren das Schädel-Hirn-Trauma, Wirbelkörper- und Unterschenkelfrakturen. Für diese zeigte sich keine Häufung im Jahresverlauf. Proximale Humerusfrakturen traten im Winter etwa 25% häufiger auf als im Sommer, Frakturen des oberen Sprunggelenks etwa 33% häufiger. Die Gonarthrose ist im Winter doppelt so oft Behandlungsdiagnose wie im Sommer.SchlussfolgerungEs gilt zu prüfen, inwiefern logisitische Folgerungen aus diesen Ergebnissen eine Effizienzsteigerung bewirken können. Das zugrunde liegende Analyseverfahren ist generell für jedes Klinikum anwendbar und stellt ein valides Controlling-Instrument dar.AbstractBackgroundRecording DRGs and diagnoses allows their distribution to be shown over the course of the year. Thus, cumulative seasonal occurrence of diseases can be detected.Patients and methodsFrom 2004 to 2010 we recorded 22,293 main diagnoses and DRGs at the clinic for trauma surgery. Injuries with the same localization and treatment were pooled.ResultsThe most frequent injuries were concussion, followed by spinal and lower leg fractures. They showed no seasonal accumulation. Proximal fractures of the humerus occurred approx. 25% more often in winter and ankle fractures about 33% more frequently. The diagnosis of osteoarthritis of the knee is twice as high in the winter as in the summer.ConclusionIt has to be verified if logistic conclusions of these results can lead to more efficiency in a hospital. The underlying analysis is applicable for every hospital and poses a valid controlling tool.BACKGROUND Recording DRGs and diagnoses allows their distribution to be shown over the course of the year. Thus, cumulative seasonal occurrence of diseases can be detected. PATIENTS AND METHODS From 2004 to 2010 we recorded 22,293 main diagnoses and DRGs at the clinic for trauma surgery. Injuries with the same localization and treatment were pooled. RESULTS The most frequent injuries were concussion, followed by spinal and lower leg fractures. They showed no seasonal accumulation. Proximal fractures of the humerus occurred approx. 25% more often in winter and ankle fractures about 33% more frequently. The diagnosis of osteoarthritis of the knee is twice as high in the winter as in the summer. CONCLUSION It has to be verified if logistic conclusions of these results can lead to more efficiency in a hospital. The underlying analysis is applicable for every hospital and poses a valid controlling tool.

Infiltration of the pes anserinus complex by an extraarticular diffuse-type giant cell tumor (D-TGCT)

This report describes the case of a 26-year-old woman with a recurrent extraarticular diffuse-type tenosynovial giant cell tumor (D-TGCT) of the medial region of the knee affecting the pes anserinus and hamstring tendons. Presurgical MRI did not exclude infiltrative properties of the tumor. In the histological evaluation, the tumor showed an aggressive dispersion by infiltrating the collagenous tissue of the hamstring tendons. The treatment included a resection of the pes anserinus complex with distal semitendinosus and gracilis tendons. Regarding extraarticular D-TGCT a review of the literature showed a predominant affection of the medial region of the knee and thigh.

Mittelfristige klinische und radiologische Ergebnisse nach autologer osteochondraler Transplantation unter Berücksichtigung der Lebensqualität

BACKGROUND Treatment of full-thickness cartilage defects remains a challenge in musculoskeletal surgery. Autologous osteochondral transplantation represents a possible solution for the repair of affected areas. However, some problems like degenerative changes of the transplanted cylinders and the surrounding cartilage or lack of cylinder integration to the surrounding cartilage arise with this method. Thus mid-term results respecting the quality of life are useful for assessment of the method. PATIENTS/MATERIAL AND METHODS We investigated 22 patients with a mean follow-up of 88 ± 14.5 months after autologous osteochondral transplantation due to a full-thickness cartilage defect of the medial femoral condyle. Beside clinical scores we assessed at follow-up the quality of life using the SF-36 health survey and the EQ-5D. Furthermore, radiological changes were detected and MRI was performed in 21 patients. A control group of 19 patients, treated with microfracture, was matched in terms of BMI, gender and age. Exclusion criteria for this group were tibial kissing lesion, ligament instability, arthrosis and malalignment. RESULTS In a longitudinal comparison with results 13.5 months after operation, no difference in Lysholm score was found. In plain radiographs higher degrees of arthritic changes in the medial compartment compared to the unaffected knee were observed. MRI revealed a mean modified MOCART score of 41.2 ± 7.7 for the OAT group and of 39.4 ± 16.1 for the microfracture group, without being significant. For OAT patients all cylinders showed an osseous integration. However, cylinder oedema was found in 9 patients. Those patients had a higher intensity of pain on a visual analogue scale. Quality of life was better for OAT patients in the physical scale of SF-36, but not in the mental scale. CONCLUSION Autologous osteochondral transplantation has an unaltered significance in treating full-thickness cartilage defects and leads to satisfying mid-term results. The development of early arthritic changes might not be preventable by this method. Oedema of the transplanted cylinders is attended by higher pain intensity and might be an indirect sign of cartilage degeneration.

Saisonale Verteilung klinischer Kennzahlen (DOC-Study)

ZusammenfassungHintergrundDas Diagnosis-related groups(DRG)-System wurde 2004 verpflichtend in Deutschland eingeführt. „Case mix“ (CM), „case mix index“ (CMI) und die Fallzahl sind grundlegende Kennzahlen. Sowohl deren saisonale Verteilung und auch die Verteilung von Hauptdiagnosen und DRGs könnten zu logistischen Konsequenzen im Krankenhaus führen.MethodikZwischen 2004 und 2013 wurden alle Hauptdiagnosen und DRGs der stationären Patienten der unfallchirurgischen Klinik des Universitätsklinikums Leipzig erfasst. Die monatliche und saisonale Verteilung wurde mittels ANOVA analysiert.ErgebnisseDie durchschnittliche monatliche Fallzahl betrug 265 ± 25, der durchschnittliche CM 388,50 ± 51,75, der CMI 1,46 ± 0,15 jeweils ohne signifikante saisonale Häufung (p > 0,1). Die Gehirnerschütterung war die häufigste Diagnose im beobachteten Zeitraum (3739 Fälle) gefolgt von proximalen Humerusfrakturen (699). Signifikante Verteilungsunterschiede konnten für Humeruskopffrakturen im monatlichen (p = 0,018) sowie jahreszeitlichen Vergleich (p = 0,006) mit einem Maximum im Winter gezeigt werden. Auch Radius- (p = 0,01) und Außenknöchelfrakturen (p ≤ 0,001) treten im Winter am häufigsten auf. Weichteilverletzungen der Schulter sind im Frühjahr am seltensten (p = 0,04). DRGs weisen keine saisonale Verteilungshäufung auf (p > 0,1).DiskussionDie signifikante Häufung von Verletzungen in bestimmten Monaten/Jahreszeiten sollte in Bezug auf logistische Konsequenzen in einer Klinik berücksichtigt werden (OP-Kapazität, Personalanforderung). Zur Erstellung einer Bedarfsanalyse ist die Betrachtung der Diagnosen besser geeignet als die von DRGs.AbstractObjectivesThe German diagnosis-related groups remuneration system (G-DRG) was implemented in 2004 and patient-related diagnoses and procedures lead to allocation to specific DRGs. This system includes several codes, such as case mix (CM), case mix index (CMI) and number of cases. Seasonal distribution of these codes as well as distribution of diagnoses and DRGs may lead to logistical consequences for clinical management.MethodsFrom 2004 to 2013 all the main diagnoses and DRGs for inpatients were recorded. Monthly and seasonal distributions were analyzed using ANOVA.ResultsThe average monthly number of cases was 265 ± 25 cases, the average CM was 388.50 ± 51.75 and the average CMI was 1.46 ± 0.15 with no significant seasonal differences (p > 0.1). Concussion was the most frequently occurring main diagnosis (3739 cases) followed by fractures of the humeral head (699). Significant distribution differences could be shown for humeral head fractures in monthly (p = 0.018) and seasonal comparisons (p = 0.006) with a maximum in winter. Radius (p = 0.01) and ankle fractures (p ≤ 0.001) also occurred most frequently in winter. Non-bony lesions of the shoulder were significantly less in spring (p = 0.04). The DRGs showed no evidence of a monthly or seasonal clustering (p > 0.1).ConclusionThe significant clustering of injuries in specific months and seasons should lead to logistic consequences (e.g. operating room slots, availability of nursing and anesthesia staff). For a needs assessment the analysis of main diagnoses is more appropriate than DRGs.OBJECTIVES The German diagnosis-related groups remuneration system (G-DRG) was implemented in 2004 and patient-related diagnoses and procedures lead to allocation to specific DRGs. This system includes several codes, such as case mix (CM), case mix index (CMI) and number of cases. Seasonal distribution of these codes as well as distribution of diagnoses and DRGs may lead to logistical consequences for clinical management. METHODS From 2004 to 2013 all the main diagnoses and DRGs for inpatients were recorded. Monthly and seasonal distributions were analyzed using ANOVA. RESULTS The average monthly number of cases was 265 ± 25 cases, the average CM was 388.50 ± 51.75 and the average CMI was 1.46 ± 0.15 with no significant seasonal differences (p > 0.1). Concussion was the most frequently occurring main diagnosis (3739 cases) followed by fractures of the humeral head (699). Significant distribution differences could be shown for humeral head fractures in monthly (p = 0.018) and seasonal comparisons (p = 0.006) with a maximum in winter. Radius (p = 0.01) and ankle fractures (p ≤ 0.001) also occurred most frequently in winter. Non-bony lesions of the shoulder were significantly less in spring (p = 0.04). The DRGs showed no evidence of a monthly or seasonal clustering (p > 0.1). CONCLUSION The significant clustering of injuries in specific months and seasons should lead to logistic consequences (e.g. operating room slots, availability of nursing and anesthesia staff). For a needs assessment the analysis of main diagnoses is more appropriate than DRGs.

Endoscopic Removal of a Scapular Osteophyte Using Scapulothoracic Arthroscopy

This article describes the removal of a scapular osteophyte from the subscapular space by scapulothoracic arthroscopy. The endoscopic technique allows a gentle approach to the subscapular space without causing a large amount of surgical trauma and therefore leads to good cosmetic and functional results.

Osteoid Osteoma of the Proximal Fibula: An Uncommon Location with the Indication for Open Surgery

Purpose. This is a case report of a patient with an osteoid osteoma of the proximal fibula. The objective is to illustrate a rare tumor location that requires open surgery due to closeness of neurological structures. Methods. Clinical and roentgenographic findings, treatment, and histological appearance are presented. Results. Local pain and swelling of the proximal fibula with improvement under salicylates led to the diagnosis of an osteoid osteoma, what was confirmed with an MRI scan. Due to proximity to the common peroneal nerve, we decided for open surgery. During the operation, the nerve was seen to cross the tumor site making it necessary to retract it to expose the entire tumor. Histologically, typical features of osteoid osteoma with a rather well-defined nidus surrounded by sclerotic bone were seen. A complete removal was performed. Conclusion. Osteoid osteomas of the proximal fibula are rare. When planning surgery, the common peroneal nerve must be identified, and its further distal course should be taken into account to avoid iatrogenic damage to the nerve.