Christina Roll

Influence of the growth factors PDGF‐BB, TGF‐β1 and bFGF on the replicative aging of human articular chondrocytes during in vitro expansion

Decreasing replicative potential and dedifferentiation of articular chondrocytes during expansion in cell culture are essential limitations for tissue engineering and cell therapy approaches. Telomeres and telomerase play a key role in cell development, aging, and tumorigenesis. There is evidence that growth factors are involved in regulating telomerase activity. Therefore, the objective was to evaluate the effect of selected growth factors on telomere biology of serially passaged chondrocytes. Human articular chondrocytes were isolated from cartilage of three patients undergoing total knee arthroplasty. The chondrocytes were cultured in monolayer with the growth factors PDGF‐BB, TGF‐β1, and bFGF. Telomere length was measured by telomere restriction fragment length assay, and telomerase activity was determined by quantifying the gene expression of its catalytic subunit hTERT by rtPCR. Chondrocytes cultured with PDGF‐BB and TGF‐β1 showed a significantly higher proliferation rate than control cells. None of the growth factor cultures revealed an accelerated rate of telomere shortening. Telomerase was not expressed in significant amounts in any of the chondrocyte cultures. Growth factor treatment of chondrocyte cell cultures for cell therapy purposes can be regarded as safe in terms of telomere biology.

Outcome after complex trauma of the foot

BACKGROUNDnIn 1997, H. Zwipp. proposed a 5-point scoring system for the classification of complex trauma of the foot. However, outcome and quality of life after this type of injury have not been studied systematically.nnnPATIENTSnSeventy-four patients with a complex injury of the foot were treated between 2001 and 2007. Fifty patients met the inclusion criteria for a prospective cross-sectional study. American Foot and Ankle Society score, the Short Form 12, and the Visual Analogue Scale-Foot and Ankle Score were recorded. All patients were examined by an experienced orthopedic surgeon and a certified pedorthist. Functional assessment was completed by dynamic baropedography.nnnRESULTSnPrimary amputation was necessary in 11, secondary amputation in 7 patients. A compartment syndrome was diagnosed in 29 patients. Soft tissue coverage was achieved in eight patients using a free vascular flap. The complication rate was 32%. Mean follow-up was 4 years (1-7 years). At that time, the American Foot and Ankle Society score was 66.2, the Short Form 12 score 38.2 (physical health component scale), and the Visual Analogue Scale-Foot and Ankle score was 51.9. Orthopedic shoes were necessary in 44% of the patients; however, compliance was low, and 52% of the orthopedic devices were insufficient. Pedographic evaluation demonstrated changes in gait in 82% of the patients.nnnCONCLUSIONnEarly outcome after complex trauma of the foot was essentially determined by soft tissue injury, whereas long-term outcome was determined more by the trauma of the bones and joints. Objective measurements such as dynamic pedography helped to better understand patients limitations. Orthotic supply could be improved in a reasonable number of the patients.

[The minimally invasive stabilization of the dorsal pelvic ring with the transiliacal internal fixator (TIFI)--surgical technique and first clinical findings].

ZusammenfassungDer transiliakale Fixateur interne (TIFI) ist eine Technik zur minimal-invasiven Stabilisierung von Iliosakralfugensprengungen sowie lateralen und transforaminalen Sakrumfrakturen. Über Mini-Inzisionen werden beidseits 7,0xa0mm USS-Pedikelschrauben (Universal-Spine-System, Synthes) 1–2 cm kranial der Spina iliaca posterior superior parallel zur Linea glutea posterior eingebracht. Der Schraubenverbindungsstab wird subfaszial eingeschoben und mit den Pedikelschrauben winkelstabil verbunden.In einer prospektiven Studie traten bei einem Kollektiv von 31 Patienten mit vertikal instabilen Beckenbrüchen, die mit dem TIFI stabilisiert wurden, 2 Wundinfektionen sowie 1 Implantatlockerung auf. Implantatfehllagen sowie implantatbedingte Gefäß-Nerven-Läsionen wurden nicht beobachtet. 2xa0Jahre postoperativ zeigten sich bei den Typ-C-Instabilitäten 50% gute bis sehr gute Ergebnisse. Die ersten Erfahrungen zeigen somit, dass sich mit dem TIFI sowohl IS-Fugensprengungen als auch laterale und transforaminale Sakrumfrakturen stabilisieren lassen. Eine geschlossene Reposition und minimal-invasive Implantationstechnik sind dabei möglich. Bei einem sehr geringen Risiko von intraoperativen Gefäß- und Nervenverletzungen bietet der TIFI eine ausreichende biomechanische Stabilität.AbstractThe Trans Iliacal Internal Fixator (TIFI) is a minimally invasive technique for the stabilization of sacro-iliac joint ruptures and fractures lateral to the sacral ala or through the sacral foramen. In this study, 7.0xa0mm pedicle screws of the Universal-Spine-System (USS, Synthes) were inserted 1–2xa0cm on the cranial side of the posterior superior iliac spine and parallel to the superior gluteal line. The connecting bar was inserted subfascially and fixed with the locking head pedicle screws to form an fixed-angle construction. In a prospective study 31 patients with vertical shear injuries of the pelvis were treated with the TIFI. There were two wound infections and one loosening of a pedicle screw. None of the screws were incorrectly positioned and no neuro-vascular lesions were caused by the implant. 2 years postoperatively we found 50% good and excellent results for type C pelvic ring injuries.Early findings show that the TIFI is well suited to stabilization of sacro-iliac joint ruptures and fractures of the lateral sacrum. Closed reduction and minimally invasive insertion technique are possible. The implant leads to sufficient biomechanical stability but there is a very low intraoperative risk of neuro-vascular lesion.

Osteo-fasciocutaneous parascapular flap transfer for reconstruction of the first ray of the foot

BackgroundSevere bone and soft tissue defects of the first metatarsal bone after trauma, tumor resection or osteomyelitis are challenging to treat. Partial amputation of the foot may be the consequence. However, due to its significance for gait, salvage of the first ray should be considered, whenever possible. One option for bone and soft tissue reconstruction, therefore, might be an osteo-fasciocutaneous parascapular flap transfer.MethodsFive patients with bone and soft tissue defects of the first ray of the foot but intact MTP joint were treated with osteo- fasciocutaneous parascapular flap transfer, two after tumor resection, and three after severe bone and soft tissue trauma. Patients were followed for 12–36xa0months clinically and radiologically.ResultsAll flaps survived. One revision was necessary because of venous thrombosis, which was treated successfully by thrombectomy and patch plastic. All osteosyntheses united and the scapular bone transplant adapted nicely to the new loading conditions. All patients were content with the result and would agree to have the operation again. Two patients were able to stand tiptoe and go jogging, one patient still had limitations of ADLs due to the concomitant injuries.ConclusionThe osteo- fasciocutaneous flap proved to be very versatile and safe for foot reconstruction due to its favorable vascular anatomy. In all patients (partial), amputation of the foot could be avoided.

Die minimal-invasive Stabilisierung des dorsalen Beckenrings mit dem transiliakalen Fixateur interne (TIFI)

ZusammenfassungDer transiliakale Fixateur interne (TIFI) ist eine Technik zur minimal-invasiven Stabilisierung von Iliosakralfugensprengungen sowie lateralen und transforaminalen Sakrumfrakturen. Über Mini-Inzisionen werden beidseits 7,0xa0mm USS-Pedikelschrauben (Universal-Spine-System, Synthes) 1–2 cm kranial der Spina iliaca posterior superior parallel zur Linea glutea posterior eingebracht. Der Schraubenverbindungsstab wird subfaszial eingeschoben und mit den Pedikelschrauben winkelstabil verbunden.In einer prospektiven Studie traten bei einem Kollektiv von 31 Patienten mit vertikal instabilen Beckenbrüchen, die mit dem TIFI stabilisiert wurden, 2 Wundinfektionen sowie 1 Implantatlockerung auf. Implantatfehllagen sowie implantatbedingte Gefäß-Nerven-Läsionen wurden nicht beobachtet. 2xa0Jahre postoperativ zeigten sich bei den Typ-C-Instabilitäten 50% gute bis sehr gute Ergebnisse. Die ersten Erfahrungen zeigen somit, dass sich mit dem TIFI sowohl IS-Fugensprengungen als auch laterale und transforaminale Sakrumfrakturen stabilisieren lassen. Eine geschlossene Reposition und minimal-invasive Implantationstechnik sind dabei möglich. Bei einem sehr geringen Risiko von intraoperativen Gefäß- und Nervenverletzungen bietet der TIFI eine ausreichende biomechanische Stabilität.AbstractThe Trans Iliacal Internal Fixator (TIFI) is a minimally invasive technique for the stabilization of sacro-iliac joint ruptures and fractures lateral to the sacral ala or through the sacral foramen. In this study, 7.0xa0mm pedicle screws of the Universal-Spine-System (USS, Synthes) were inserted 1–2xa0cm on the cranial side of the posterior superior iliac spine and parallel to the superior gluteal line. The connecting bar was inserted subfascially and fixed with the locking head pedicle screws to form an fixed-angle construction. In a prospective study 31 patients with vertical shear injuries of the pelvis were treated with the TIFI. There were two wound infections and one loosening of a pedicle screw. None of the screws were incorrectly positioned and no neuro-vascular lesions were caused by the implant. 2 years postoperatively we found 50% good and excellent results for type C pelvic ring injuries.Early findings show that the TIFI is well suited to stabilization of sacro-iliac joint ruptures and fractures of the lateral sacrum. Closed reduction and minimally invasive insertion technique are possible. The implant leads to sufficient biomechanical stability but there is a very low intraoperative risk of neuro-vascular lesion.

Calcaneocuboid joint involvement in calcaneal fractures.

BACKGROUNDnThe reported incidence of calcaneocuboid joint (CCJ) involvement in calcaneal fractures varies considerably. It is largely unknown to what extent CCJ involvement accounts for outcome in these fractures. Therefore, the goal of this study was to analyze the incidence and effects of CCJ involvement in calcaneal fractures.nnnMETHODSnThe clinical records of 106 patients, treated between 2000 and 2004, were reviewed for fracture classification, injury mechanism, surgical treatment, and complications. In a prospective cross-sectional study, 44 patients were assessed clinically (SF-36 American Orthopaedic Foot and Ankle Society score) and radiographically. Gait analysis was performed using dynamic pedography.nnnRESULTSnSixty-eight percent of all fractures had involvement of the CCJ. Fractures with CCJ involvement were caused by a more severe injury than fractures without CCJ involvement (Mann-Whitney U test, p = 0.03); this is reflected by a strong association between CCJ involvement and fracture classification (Spearman, p < 0.006). Patients with involvement of the CCJ-especially those with a postoperative step in the CCJ-achieved a lower SF-36 score as well as a lower American Orthopaedic Foot and Ankle Society score than patients without CCJ involvement. CCJ involvement was associated with more difficulties in walking on rough surface (Spearman, p = 0.020). Limitations during gait were confirmed by dynamic pedography. Grading of posttraumatic osteoarthritis was associated with fracture classification (chi test p < 0.02) and quality of reduction (chi test p < 0.01).nnnCONCLUSIONSnThese results indicate that calcaneal fractures with involvement of the CCJ are associated with more severe trauma and worse outcome. Thus, the CCJ should be given more credit during surgery and in our research efforts.

Evaluation of hyperbaric oxygen therapy for free flaps using planar optical oxygen sensors. Preliminary results

OBJECTIVESnThis study was designed to determine if a) hyperbaric oxygen increases the tissue oxygenation of free flaps and b) verification of this effect is possible by using a recently validated and innovative method for two-dimensional pO₂ measurement (Luminescence lifetime imaging = LLI).nnnMETHODSnSix patients with a free parascapular flap transplanted to the lower limb received hyperbaric oxygen (HBOT) therapy. The HBOT regimen consisted of treatment over 90 minutes with 100% O₂ (FiO₂ 1.0) at 240 kPa (Marx-Schema). The transcutaneous oxygen partial pressure (ptcO₂) was measured over the entire flap with the use of luminescence lifetime imaging (LLI) before and 30, 60, 120 minutes after treatment. The LLI is based on the oxygen dependent quenching of phosphorescence of the indicator dye platinum (II)-octaethyl-porphyrin implemented in a polystyrene sensor foil.nnnRESULTSnIn all six free flaps we could find a significant increase of tissue oxygen over the entire flap in form of increased R-values as well as subsequently calculated absolute ptcO₂ values over a period of 120 min after hyperbaric therapy. The ptcO₂ values increased significantly from 42.59 ± 1.11 Torr before to 81.14 ± 5.95 Torr after hyperbaric treatment (p < 0.001). Even after 2 hours the ptcO₂ values were significantly higher (83.45 ± 13.80 Torr) compared with values prior to HBOT (p < 0.006).nnnCONCLUSIONSnThe findings of this study demonstrated an increase of oxygen supply over the entire flap after hyperbaric oxygen therapy.

Temperature Profile of Radiofrequency Probe Application in Wrist Arthroscopy: Monopolar Versus Bipolar

PURPOSEnThe purpose of this study was to investigate the changes in temperature during wrist arthroscopy comparing monopolar and bipolar radiofrequency energy (RFE).nnnMETHODSnA standard wrist arthroscopy was performed on 14 arms of 7 cadavers without irrigation or with continuous irrigation with 0.9% saline solution and gravity-assisted outflow through an 18-gauge needle. We treated 7 wrists with a bipolar device (VAPR II with 2.3-mm side effect electrodes; DePuy Mitek, Westwood, MA) and 7 wrists with a monopolar device (OPES Ablator for small joints, 45°; Arthrex, Naples, FL). The temperature was recorded simultaneously from 7 predefined anatomic landmarks.nnnRESULTSnWe observed an increase in the temperature corresponding to the time of energy application. The highest measured peak temperatures were 52°C (monopolar) and 49.5°C (bipolar) without irrigation. Continuous irrigation led to a significant reduction in the temperature at the site of the energy application. The mean temperature decreased by 7°C for the monopolar system and 5°C for the bipolar system when irrigation was used. For both radiofrequency devices, we found a decrease in the temperature proportional to the distance of the sensors to the radiofrequency probe.nnnCONCLUSIONSnMonopolar and bipolar RFE can be safely used in wrist arthroscopy if a continuous irrigation system is applied and the energy impulse does not exceed 5 to 10xa0seconds. However, it should be used with great care to avoid local heat damage especially at the cartilage.nnnCLINICAL RELEVANCEnThis basic science study was performed to gain data concerning the temperature in wrist arthroscopy and to broaden the knowledge about the risks when using RFE. Furthermore, we sought to control side effects of RFE by finding the best applied form of RFE regarding duration and pulsation (monopolar/bipolar).

Functional donor-site morbidity following (osteo-) fasciocutaneous parascapular flap transfer.

Problem:The parascapular flap is extremely versatile in the armamentarium of the plastic surgeon. However, little is known about the donor-site morbidity. Our purpose was to investigate limitations and problems arising at the donor site of parascapular flaps. Methods:Twenty patients with free parascapular flaps were followed up over a period of 3 years. Donor-site morbidity was evaluated using standardized evaluation forms. Constant score was calculated to judge shoulder function, SF-36 score was used to evaluate patient satisfaction. Results:All flaps survived in our series. In 2 patients, delayed wound healing was recorded at the donor site. In 3 patients, shoulder function was limited. In 1 patient, the brachial plexus was affected, and another had preexisting rotator cuff disease. Scar dimensions varied considerably; however, cosmetic aspects of the donor site were not a complaint. Discussion:This is the first report evaluating donor-site morbidity of parascapular flaps. Limitations in shoulder function are low if correct operative technique with refixation of the musculature is maintained. In general, patients did not have any complaints about the cosmetic appearance of the donor site.

Value of 3D Reconstructions of CT Scans for Calcaneal Fracture Assessment

Background: The interpretation of CT scans for the evaluation of calcaneal fractures is difficult. Three-dimensional (3D) reconstruction (volume rendering technique [VRT]) has been valuable in the evaluation of irregularly shaped bones. However, their value for the analysis of calcaneal fractures is still debated. Therefore, the objective of this study was to assess the effect of additional use of 3D CTs in calcaneal fractures. Methods: In a prospective multicenter study, the CT data set of 5 different fractures was presented to 57 evaluators. First, the participating surgeons were asked to assess the fractures on the basis of axial, coronal, and sagittal reconstructions using a multiple-choice questionnaire. Second, 3D reconstructions (VRT) were presented. The CT scans were validated by the intraoperative findings and the results were compared to the model solution of 3 foot and ankle surgeons. Intra- and interrater reliabilities were calculated. Results: The proportion of intraobserver agreement was 82%, with Cohen kappa of κ = 0.748 (P < .001). Interrater agreement varied between 0.772 (P = .006) for the assessment of concomitant fractures and 0.987 (P < .001) for the suggested approach. The evaluation of several items improved after presentation of the 3D CTs (Cochrane Q test, P < .001). The benefit of 3D imaging was higher in inexperienced surgeons and complex fractures (Friedman test P < .001). Conclusion: The evaluation of CT scans of calcaneal fractures was improved by the additional use of 3D images (VRT). Level of Evidence: Level II, prospective comparative study.