[Conventional epiphyseal chondrosarcoma of childhood and adolescence: a case report]. / Konventionelles epiphysäres Chondrosarkom des Kindes- und Jugendalters: ein Fallbericht.

INTRODUCTION: Conventional chondrosarcoma is the second most common primary malignant bone tumor and usually occurs at older adult ages. It is rare in childhood and adolescence. CASE HISTORY: This case report presents the treatment course of a 13-year-old boy with a symptomatic chondrogenic tumor of the right distal femur. Histopathologically, an epiphyseal intermediate-grade chondrosarcoma (G2) was diagnosed. DISCUSSION: Based on the following case, potential radiological and histopathological differential diagnoses, such as chondroblastoma or chondroblastic osteosarcoma, are discussed against the background of current standards in orthopedic oncology.

[Treatment concepts for complications after resection and defect reconstruction of pelvic tumours]. / Behandlungskonzepte von Komplikationen nach Resektion und Defektrekonstruktion pelviner Tumoren.

BACKGROUND: Partial pelvic resection, internal hemipelvectomy or sacrectomy as a result of bone sarcoma is still challenging. No matter what kind of reconstruction is used, there is still a much higher rate of complications in pelvic surgery compared to sarcoma surgery of the long bones. OBJECTIVES: We describe the most common complications in pelvic sarcoma surgery and specific complications related to the reconstruction method. Handling strategies for these complications are specified. METHODS: We performed a literature search and report our own experiences in the troubleshooting of pelvic surgery-related complications to gain an up-to-date overview of the state-of-the-art in management strategies. RESULTS: Prospective randomized trials or meta-analyses on this topic are lacking. The literature search depicted that, besides local recurrence, deep infection after reconstruction is the most serious complication. An early revision with radical debridement has to be performed in order to save the reconstruction. In the case of a deep infection, the removal of all implants with a total loss of the reconstruction is often unavoidable. Therefore, an individualized risk-benefit analysis prior to surgery with respect to the type of reconstruction, or no reconstruction at all (hip transposition), together with the patient is advisable. CONCLUSIONS: Complications-especially infections-after hemipelvectomy or sacrectomy are common. In the case of infection, in some cases, an early revision is the only chance to prevent a reconstruction from explantation.

[Complication management following resection and reconstruction of the upper limbs and shoulder girdle]. / Komplikationsmanagement nach Tumorresektion und Defektrekonstruktion an der oberen Extremität und am Schultergürtel.

BACKGROUND: Sarcomas of the upper limbs commonly affect the proximal humerus or scapula. Complications after tumor resection and reconstruction are rare but cannot be neglected, particularly after tumor endoprosthetic reconstructions. MATERIALS AND METHODS: The most common complications after resection of sarcomas of the upper limbs and shoulder girdle are described, and current knowledge regarding complication management is presented. Additionally, a selective literature search was performed, incorporating personal experiences. RESULTS: Wound healing disorders and infections after tumor resection without specific reconstruction (clavicle resection, scapulectomy) usually respond well to conservative or surgical treatment. However, periprosthetic infections after reconstruction using a megaendoprosthesis constitute a severe and frequent complication, with an incidence of 5-10%. Two-stage implant replacement still represents the gold standard, although in selected cases, one-stage revision with retention of the prosthetic stem appears warranted. Secondary amputation as a result of periprosthetic infection is rare compared to the situation with infections of the lower limb. Mechanical complications necessitating surgical revision are mostly limited to joint dislocation after inverse total shoulder replacement (TSR). (Sub)luxation in anatomic TSR can be tolerated provided there is no tendency toward perforation of the skin in a asymptomatic patient. Biological reconstructions are most often indicated for reconstruction of intercalary defects of the humerus, and revision is necessitated most frequently by mechanical complications. Despite multiple surgical revisions, stable reconstructions and limb salvage can usually be achieved in the upper limb.

[Current results of tumour endoprosthetics in adolescents and adults]. / Aktuelle Ergebnisse der Tumorendoprothetik bei Jugendlichen und Erwachsenen.

BACKGROUND: The majority of osteoarticular defects after tumor resection in adolescent and adult patients are reconstructed using megaendoprosthetic implants. However, even infant and pre-teen children undergo reconstruction of defects using so-called growing prostheses with an increasing frequency. OBJECTIVES: Presentation of current techniques, outcomes and the most common complications of megaendoprosthetic reconstruction following tumour resection. METHODS: Selective literature review and discussion of current concepts and knowledge in megaendoprosthetic reconstruction against personal experience and treatment strategies. RESULTS: Megaendoprosthetic reconstructions achieve good functional results and long-term limb salvage (ca. 90% of cases) in adolescent and adult patients. Still, periprosthetic infection and mechanical failure of joint components are among the most common complications observed. In infant and pre-teen children treated by reconstruction using a growing prosthesis, mandatory maintenance operations-in the process of elongating the implant-must also be considered when assessing complication risks. CONCLUSIONS: Megaendoprosthetic reconstructions of osteoarticular defects are a standard procedure in adolescent and adult patients. Despite a substantial complication rate, limb salvage is achieved in a majority of patients. When using growing prostheses in younger children, one needs to be aware of additional servicing procedures that occur independently of those arising from complications.

[Endoprostheses for stump formation after hip disarticulation]. / Endoprothesen zur Stumpfbildung nach Hüftexartikulation.

BACKGROUND: Hip disarticulation is a psychologically and physically demanding procedure. However, it remains a therapeutical option whenever limb salvage proves impossible due to sarcoma, severe implant-associated infections or trauma. The stump lengthening procedure (SLP) is a surgical technique that allows partial salvage of the thigh through endoprosthetic proximal femur replacement after hip disarticulation, depending on the amount of viable soft tissue coverage. This leads to a more appealing visual appearance, facilitates prosthetic fitting and significantly improves limb function. OBJECTIVES: Description of indications for SLP, surgical technique, presentation of clinical and functional outcomes. METHODS: Review of applying literature and presentation of outcomes of our own SLP collective. RESULTS: The risk of local recurrence does not increase after SLP compared to hip disarticulation. While the majority of patients can be fitted with an exoprosthesis, a walking aid is usually necessary for ambulation. Exoprostheses are usually worn throughout the entire day, and patients manage distances of a mean of 2000 metres, even if reconstruction lengths are less than 10 cm. Patients aged 50 years or older tend to wear their exoprosthesis for shorter periods of daywear and achieve significantly poorer functional scores. Postoperative complications are common at a rate of 52%. Periprosthetic infection (21%) and soft tissue perforation of the implant with subsequent implant-associated infection (14%) were the most severe complications observed. CONCLUSIONS: The stump lengthening procedure poses a feasible alternative to classic hip disarticulation in patients with multiple prior operations and/or advanced stages of disease. It leads to satisfactory cosmetic and functional results without jeopardizing local tumor control. Stump perforation presents as the most common complication. Apart from improving the ability to sit down comfortably, both patients treated with a curative and palliative intent manage to ambulate using exoprostheses. With increasing age at the time of operation, walking aids are necessary for ambulation.

[Instability after operative and conservative treatment of isolated Mason type II fractures]. / Instabilität nach operativer und konservativer Versorgung von isolierten Mason-II-Frakturen.

BACKGROUND: Radial head fractures are the most frequent fractures of the elbow joint in adults. For Mason type II fractures without concomitant injuries favorable results have been shown with operative and conservative management. There is insufficient evidence concerning elbow joint stability after conservative treatment compared to open reduction and internal fixation (ORIF). MATERIALS AND METHODS: All patients with isolated Mason type II (two part fracture displaced >2 mm and <5 mm) radial head fractures between 1 January 2003 and 1 April 2013 were retrospectively reviewed. Exclusion criteria were age <18 years, associated fractures of the ipsilateral extremity or elbow luxation. A total of 50 patients (mean age 44.2 years, range 19-71 years) who received either ORIF (n = 31) or conservative treatment (n = 19) were included. The mean follow-up was 43.2 months (range 9-61 months). Patients were evaluated using the Disability of the Arm, Shoulder and Hand (DASH) score, Mayo Elbow Performance score (MEPS), and Oxford Elbow score (OES). Joint stability (varus and valgus stress) was assessed under fluoroscopy and a distinction was made between slight instability (angulation <10°), moderate instability (angulation ≥10°) and gross instability (elbow dislocation). RESULTS: Residual fracture displacement (conservative: 2.7 mm, ORIF: 1.4 mm, p < 0.042) and varus/valgus joint stability (3% ORIF vs. 26% conservative, p = 0.031) showed significant differences. The stability as tested by a radiological dynamic procedure showed an instability after ORIF in 3% of the joints compared to 26% after conservative treatment; however, this did not influence the short to mid-term clinical outcome: No significant differences were found in the DASH score (conservative 33 points, ORIF 36 points), MEPS (conservative 76 points, ORIF 78 points) and OES (conservative 41 points, ORIF 43 points). DISCUSSION: Both conservative management and operative treatment had a good functional outcome. Operative treatment showed a positive tendency concerning radiological and functional outcome without statistical significance.

[Is the discharge letter still relevant? : Chances and risks of "Medical apps" in orthopedics and traumatology]. / Ist der Entlassungsbrief noch zeitgemäß? : Chancen und Risiken von "Medical Apps" in Orthopädie und Unfallchirurgie.

CURRENT SITUATION: The discharge letter currently represents the gold standard of the information and transfer document in the field of inpatient orthopedic and trauma patient care. In the age of digitization, the smartphone is penetrating more and more areas of life as an omnipresent internet access medium and is thus fundamentally influencing the awareness of our society. Whereas the use of applications on smartphones is already well established today, the range of medical apps is rudimentary. The potential of apps on smartphones as an innovative digital communication medium is undeniable, but the currently available medical apps in orthopedics and trauma surgery are available to a small patient clientele only. FORECAST: Currently, the use of medical apps is not an adequate alternative to the discharge letter. However, it is only a matter of time before the innovative potential of applications is used as a communication tool in outpatient and inpatient care. It is, therefore, essential to start creating the legal, ethical and medical framework and to establish a relevant regulatory body.

[The acetabulum nonunion: reconstruction and reosteosynthesis : A long-term outcome]. / Die Acetabulumpseudarthrose: Rekonstruktion und Reosteosynthese : Ein Langzeitergebnis.

Acetabular nonunions are rare, especially after operative treatment of an acetabular fracture. There are only single reports of the reconstruction and therapy of acetabular nonunion. Furthermore, there are fewer reports for treatment of acetabular nonunion with a long follow-up. We report a successful revision of an acetabular nonunion after transversal fracture and previous operative intervention, as well as the long-term follow-up after revision surgery.

[Necrotizing fasciitis - a clinical diagnosis]. / Nekrotisierende Fasziitis ­ eine klinische Diagnose.

Necrotizing fasciitis is a life-threatening clinical pattern, which may lead to multi-organ failure and death with delayed diagnosis or inadequate treatment. We report on a 68-year old patient who developed necrotizing fasciitis of the right elbow with multiorgan failure and long-term ventilation after an accidental and minor injury. The patient survived as a result of an early diagnosis and surgical intervention. In this case report we want to clarify the diagnosis and treatment of necrotizing fasciitis and give an overview of the recent literature on the topic.

Veno-venous extracorporeal membrane oxygenation in obese surgical patients with hypercapnic lung failure.

BACKGROUND: In patients with a body mass index (BMI) > 35 kg/m(2) , or in extreme cases weighting > 250 kg, we are faced with special challenges in therapy and logistics. The aim was to analyze the feasibility of the extracorporeal membrane oxygenation (ECMO) in these patients. METHODS: We report 12 adult patients [10 male, 2 female; mean age 56.7 (34-74) years; mean BMI 47.9 (35-88.6) kg/m(2) ] with acute lung failure treated with veno-venous ECMO from 1 January 2009 to 30 June 2013. All patients were cannulated percutaneously into the right internal jugular vein and one of the femoral veins at the bedside. RESULTS: The mean time to ECMO after admission to the intensive care unit (ICU) was 2 days (0-10), and the mean ECMO run time was 9 days (4 h-20 days). Lung failure occurred in the contexts of wound infection (two patients), anaphylactic shock (one patient), major trauma (one patients) and pneumonia after surgery (four patients), and respiratory failure in abdominal sepsis (four patients). The mean time in the ICU was 31 days (0-89), and the mean time at the hospital was 38 days (0-101). Three patients died on the system because of multiorgan failure; nine patients were weaned from ECMO (75%); and six were patients discharged from the ICU and from the hospital (survival rate 50%). CONCLUSIONS: ECMO in obese patients is feasible and life saving. Therefore, a percutaneous cannulation remains feasible. The goals of the ECMO therapy include early spontaneous breathing, tracheotomy, rapid reduction of sedation and adequate analgesia. Rehabilitation includes nutritional therapy, as well as psychiatric therapy and bariatric surgery, as perspectives for the future.

[Management of the cut-out of various forms of osteosynthesis for proximal femoral fractures]. / Management des Cut-out verschiedener Osteosyntheseformen bei proximalen Femurfrakturen.

Proximal femoral fractures are a common type of injury in older people. A cut-out of the femoral neck screw after initial osteosynthetic surgery of proximal femoral fractures is a frequent and feared complication. There could be different causes for cut-outs. Osteoporosis and necrosis of the femoral head could be biological reasons for cut-outs; however, mechanical factors, such as reduction, implant position and morphological characteristics of fractures also have a major influence on the cut-out rate. The treatment of the cut-out is often complex and depends on the destruction of the femoral head and the acetabulum. If the bone quality is still good and the head is not completely destroyed, a reosteosynthesis can be performed. Conversion to an endoprosthetic replacement is often the only possibility. Endoprosthetic treatment is often complex and associated with a high morbidity.

Impact of topography and added TiN-coating on adult human dermal fibroblasts after seeding on titanium surface in-vitro.

Complications of transcutaneous osseointegrated prosthetic systems (TOPS) focus on the metal-cutaneous interface at the stoma. Besides pain due to scare tissue as well as undefined neuropathic disorders, there is high evidence that the stoma presents the main risk causing hypergranulation and ascending infection. To restore the cutaneous barrier function in this functional area, soft-tissue on- or in-growth providing a vital and mechanically stable bio-artificial conjunction is considered a promising approach. In this study we assessed viability and proliferation of adult human dermal fibroblasts (HDFa) on modifications of a standard prosthetic titanium surface. Un-coated (TiAl6V4) as well as a titanium-nitrite (TiN) coated additive manufactured porous three-dimensional surface structures (EPORE®) were seeded with HDFa and compared to plain TiAl6V4 and polystyrene surfaces as control. Cell viability and proliferation were assessed at 24 h and 7 days after seeding with a fluorescence-based live-dead assay. Adhesion and cell morphology were analyzed by scanning electron microscopy at the respective measurements. Both EPORE® surface specifications revealed a homogenous cell distribution with flat and spread cell morphology forming filopodia at both measurements. Proliferation and trend to confluence was seen on un-coated EPORE® surfaces with ongoing incubation but appeared substantially lower on the TiN-coated EPORE® specification. While cell viability on both EPORE® specifications was comparable to plain TiAL6V4 and polystyrene controls, cell proliferation and confluence were less pronounced when compared to controls. The EPORE® topography allows for fibroblast adhesion and viability in both standard TiAl6V4 and - to a minor degree - TiN-coated specifications as a proof of principle.

[Intramedullary nailing of coated and uncoated nails in infected tibial pseudarthrosis : Results of a retrospective examination of 56 patients]. / Intramedulläre Nagelung von beschichteten und unbeschichteten Nägeln bei Tibia-Infektpseudarthrosen : Ergebnisse einer retrospektiven Untersuchung von 56 Patienten.

BACKGROUND: In surgery for sepsis it is a well-established principle that no internal osteosynthetic material should be implanted in cases of chronic osteomyelitis. Therefore, the surgical treatment with intramedullary nails is so far used only rarely in cases of chronic osteomyelitis. OBJECTIVE: This study analyzed whether the implantation of tibial intramedullary nails is an effective treatment for chronic osteomyelitis and how high is the rate of reinfection. MATERIAL AND METHODS: A retrospective analysis of patients with an infected pseudarthrosis of the tibia in whom a gentamycin-coated nail (ETN) or an uncoated tibial intramedullary nail (UCN) was implanted between December 2011 and December 2019 was carried out. The preoperative, perioperative and postoperative results were evaluated. RESULTS: During the study period 29 patients received a UCN and 27 patients received an ETN. Of the patients 95% (n = 53) had been previously unsuccessfully treated with external fixation. Postoperative complications occurred in 45% of the patients and more often in the ETN group (48% vs. 41%). Reexacerbation of the infection occurred in 20 patients and more frequently in the UCN group (38% vs. 33%). The nonunion already showed a bony consolidation at the time of the exacerbation in 10 patients (50%). At the end of the follow-up a consolidation was present in 48 patients (86%), more frequently in the UCN group (90% vs. 78%). Of the patients 50 (89%) reached full weight bearing without any differences between the groups. CONCLUSION: Despite a relatively high a rate of postoperative complications the risk of reinfection was acceptable with good functional and radiological results. The main general advantages of nailing are without doubt the high primary stability, the implantation with preservation of the soft tissue and the improved wearing comfort for patients.

[Success factors and obstacles in the implementation of competence-oriented teaching in surgery]. / Erfolgsfaktoren und Hindernisse bei der Implementierung kompetenzorientierter Lehre in der Chirurgie.

BACKGROUND AND OBJECTIVES: For successful competence-oriented teaching at the medical faculties it is important to identify the factors that influence its implementation in order to benefit from the strengths and balance out weaknesses. The present study examined the success factors and obstacles of the implementation of competence-oriented teaching in the surgical discipline from the point of view of students and lecturers. METHODS: After implementation of competence-oriented teaching based on the teaching goals of the NKLM, in clinical examination courses (bedside teaching and block internship, BP) at two hospitals, a qualitative content analysis and quantification of the answers were performed using focus group interviews and questionnaires with students (S) and lecturers (D). RESULTS: During the summer semester 2022 a total of 31 students and 14 lecturers were interviewed in focus groups and 143 questionnaires (123 S, 20 D) were analyzed. For the students the presence of concrete competences/teaching goals, guidelines for the lesson, transparent goals and ability to demand teaching goals as well as structured lessons and mentoring were the main success factors. Lecturers on the other hand reported the presence of concrete goals, assistance for the lesson preparation and the activity of the students as success factors. The results of the questionnaires showed that the majority (88% S, 75% D) were informed about the teaching goals and considered them to be followed (84%S, 95% D). Obstacles were the factors "time", "mentoring" and "information". Factors that were between negative and positive (indifferent factors) were "uncertainty about competence-orientation" and "uncertainty how to examine the teaching success". DISCUSSION: Transparent structure and teaching goals as well as a mentoring system are the success factors for the implementation of competence-oriented lessons and should be used as strengths. Indifferent factors represent weaknesses and need to be addressed by training and instruction. Restricted time and personnel resources are the immanent problems that hamper the implementation and require fulminant structural changes.

[Post-traumatic bipolar dislocation of the clavicle: is operative treatment reasonable?]. / Posttraumatische bipolare Luxation der Klavikula : Ist die operative Versorgung sinnvoll?

Bipolar dislocation of the clavicle ("floating clavicle") is extremely rare. It exists no standardised treatment for this trauma and the treatment is often conservative. This is mainly an anterior displacement of the sternoclavicular joint (type III according to Allman) and a posterior dislocation of the acromioclavicular joint (type IV according to Rockwood).We report on a 60 year old male who fell onto the right shoulder. He sustained a 'floating clavicle' and had a massive dislocation, impairment of range of motion and pain. Venous congestion was observable. We stabilised the dislocated acromioclavicular joint with a Balser's plate, the sternoclavicular joint was fixed with PDS cord tension band technique around the first rip and the sternum. In addition we resected the anterior part of the distal clavicle to get a better cosmetic result. Post-operatively the patient had an excellent range of motion without any further symptoms after six weeks and one year. Venous congestion was not more observable.In most of the cases dislocations of both ends of the clavicle are treated conservatively. We recommend an operative treatment especially in young and active patients to avoid re-dislocation and to archive better cosmetic results.

[Sacrum fractures and lumbopelvic instabilities in pelvic ring injuries: classification and biomechanical aspects]. / Sakrumfrakturen und lumbopelvine Instabilitäten bei Beckenringverletzungen: Klassifikation und biomechanische Aspekte.

Multiplanar posterior pelvic ring instabilities are severe injuries and typically occur in the os ilium, the sacroiliac joint, the sacrum and/or in a combination of these sites. They pose challenges to the orthopedic trauma surgeon during reconstruction, particularly when these injuries are associated with multiplanar sacral fractures and involvement of the lumbosacral junction. Due to the multidirectional forces affecting the pelvic ring, one has to have basic knowledge about the mechanism of injury, its biomechanics, and the various treatment options. In the following we give an overview on injury classifications, biomechanical aspects of the injuries and various types of operative treatments and osteosynthesis techniques.

[Anatomical and radiological aspects in lumbopelvic fixation]. / Anatomische Aspekte und Bildgebung zur lumbopelvinen Fixation.

Spinal and pelvic surgery (as in neuromuscular scoliosis or unilateral highly unstable vertical sacral fractures or unstable H- or U-shaped sacral fractures) relies on lumbopelvic fixation. This technique belongs to the standard procedures for lumbosacral injuries in orthopedic surgery. Preoperatively, a CT scan with 1 mm slices is essential to detect anatomical variants and cortical narrow nesses. For optimal insertion of pedicel screws, knowledge of the pedicle diameter and length is necessary and screws should be placed convergent to each other taking into consideration the pedicle length and angle. For placement of the iliac screws exact knowledge of the anatomy is essential to avoid cortical wall perforation and neurovascular injuries. The safest screw path was determined as the bony canal between the posterior superior iliac spine (PSIS) and the anterior inferior iliac spine (AIIS). Intraoperatively, standard fluoroscopic views allow safe placement of the screws. The aim of the following manuscript is to illustrate anatomical and morphological aspects of the spine and pelvis as well as to describe important bony landmarks and optimal intraoperative C-arm views for optimal screw insertion.

[Unilateral triangular lumbopelvic stabilization: indications and techniques]. / Unilaterale trianguläre lumbopelvine Stabilisierung: Indikationen und Technik.

Operative fixation has become treatment of choice for unstable sacral fractures. Osteosynthesis for these fractures results in loss of reduction in up to 15%. Vertical sacral fractures involving the S1 facet joint (Isler 2 and 3) may lead to multidirectional instability. Multidirectional instability of the posterior pelvic ring and lumbopelvic junction may be stabilized and forces balanced by a so-called lumbopelvic triangular fixation. Lumbopelvic triangular fixation combines vertical fixation between the lumbar vertebral pedicle and the ilium, with horizontal fixation, as an iliosacral screw or a transiliacal plate osteosynthesis. The iliac screw is directed from the posterior superior iliac spine (PSIS) to the anterior inferior iliac spine (AIIS). Thereby, lumbopelvic fixation decreases the load to the sacrum and SI joint and transfers axial loads from the lumbar spine directly onto the ilium. Triangular lumbopelvic fixation allows early full weight bearing and therefore reduces prolonged immobilization. The placement of iliac screws may be a complex surgical procedure. Thus, the technique requires thorough surgical preparation and operative logistics. Wound-related complications may occur. Preexisting Morell-Lavalée lesions increase the risk for infection. Prominent implants cause local irritation and pain. Hardware prominence and pain are markedly reduced with screw head recession into the PSIS.

[Portfolio-based learning in surgery : Making competencies "visible"]. / Portfoliobasiertes Lernen in der Chirurgie : Kompetenzen "sichtbar" machen.

BACKGROUND: Due to an increasing competence orientation of medical studies, surgical curricula are being adapted in many places. In addition to surgical knowledge and practical skills, these should also teach competencies in differential diagnostics and treatment. The teaching of surgical knowledge through lectures and seminars and the demonstration of practical skills, e.g., through the use of logbooks in the Bock Practical Surgery (BP), only allows limited active engagement with surgical competencies on differential diagnostics and treatment. A reflection-based portfolio allows, through the independent written elaboration of surgical topics, an active engagement with the competencies and promises a higher learning effect. In the context of the implementation of such a portfolio as part of the proof of activity in BP, the effects on the acquisition of competencies and on the way of learning were investigated. MATERIAL AND METHODS: Using a mixed methods approach, we compared competence acquisition using a reflection-based portfolio with learning using a logbook. Students conducted a self-assessment of competencies using questionnaire surveys before and after the BP. Through focus group interviews with discussions among students using a guideline, we explored the different ways of acquiring competencies. In addition, the examination and evaluation results of both cohorts were compared. RESULTS AND DISCUSSION: Students' self-assessed competency acquisition and examination and evaluation results showed no differences when comparing the two cohorts. During the focus group interviews, we were able to show that in the perception of the students, surgical competencies can be made more visible and thus more explicit with the help of a reflection-based portfolio. In addition, self-regulated learning was promoted without neglecting practical skills. Students demanded greater supervision and guidance by mentors in both groups.

Evaluation of articular cartilage in patients with femoroacetabular impingement (FAI) using T2* mapping at different time points at 3.0 Tesla MRI: a feasibility study.

OBJECTIVES: To define the feasibility of utilizing T2* mapping for assessment of early cartilage degeneration prior to surgery in patients with symptomatic femoroacetabular impingement (FAI), we compared cartilage of the hip joint in patients with FAI and healthy volunteers using T2* mapping at 3.0 Tesla over time. MATERIALS AND METHODS: Twenty-two patients (13 females and 9 males; mean age 28.1 years) with clinical signs of FAI and Tönnis grade ≤ 1 on anterior-posterior x-ray and 35 healthy age-matched volunteers were examined at a 3 T MRI using a flexible body coil. T2* maps were calculated from sagittal- and coronal-oriented gradient-multi-echo sequences using six echoes (TR 125, TE 4.41/8.49/12.57/16.65/20.73/24.81, scan time 4.02 min), both measured at beginning and end of the scan (45 min time span between measurements). Region of interest analysis was manually performed on four consecutive slices for superior and anterior cartilage. Mean T2* values were compared among patients and volunteers, as well as over time using analysis of variance and Student's t-test. RESULTS: Whereas quantitative T2* values for the first measurement did not reveal significant differences between patients and volunteers, either for sagittal (p = 0.644) or coronal images (p = 0.987), at the first measurement, a highly significant difference (p ≤ 0.004) was found for both measurements with time after unloading of the joint. Over time we found decreasing mean T2* values for patients, in contrast to increasing mean T2* relaxation times in volunteers. CONCLUSION: The study proved the feasibility of utilizing T2* mapping for assessment of early cartilage degeneration in the hip joint in FAI patients at 3 Tesla to predict possible success of joint-preserving surgery. However, we suggest the time point for measuring T2* as an MR biomarker for cartilage and the changes in T2* over time to be of crucial importance for designing an MR protocol in patients with FAI.