Spontaneous healing of acute ACL ruptures: rate, prognostic factors and short-term outcome.

INTRODUCTION: Anterior cruciate ligament (ACL) reconstruction is considered the first line treatment in ACL rupture. However, some patients return to high intensity sport activities and show a normal knee function without ACL reconstruction. Therefore, aim of this study was to evaluate the rate and prognostic factors of spontaneous healing in patients with ACL rupture and the short-term functional outcome. METHODS: The rate, prognostic factors and short-term functional results of spontaneous healing in patients with ACL rupture were evaluated in 381 patients. Morphology of ACL rupture and extent of posterior tibial slope (PTS) were classified by MR- and x-ray imaging. In patients with normal knee stability in anesthesia examination and healed ACL during the arthroscopy 6 weeks after trauma ACL reconstruction was canceled. IKDC -, Tegner Activity Score, KT 1000 testing and radiological characteristics were collected 12 months postoperatively in these patients. RESULTS: 14.17% of the patients with ACL rupture showed a spontaneous healing after 6 weeks. Femoral ACL-rupture (p < 0.02) with integrity of ligament stump > 50% (p < 0.001), without bundle separation (p < 0.001) and decreased PTS (p < 0.001) was found significantly more often in patients with a spontaneous healed ACL. The average IKDC score was high at 84,63 in patients with healed ACL at 1 year follow-up, but KT 1000 testing was inferior compared to non-injured side. CONCLUSION: Spontaneous healing of a ruptured ACL happened in 14% of the patients. Especially in low-demand patients with femoral single bundle lesions without increased posterior tibial slope delayed ACL surgery should be considered to await the possibility for potential spontaneous ACL healing.

Outcome of Surgical and Conservative Treatment of Patients with Shoulder Impingement Syndrome - a Prospective Comparative Clinical Study.

PURPOSE OF THE STUDY Subacromial impingement is one of the most common reasons for shoulder pain. The surgical management of this condition has recently become the focus of criticism because of the rising number of surgical procedures and the lack of superiority of surgical over conservative treatment. In this prospective comparative study, we compared standardised conservative care with surgical treatment and placed special emphasis on the patients' ability to work. MATERIAL AND METHODS A total of 106 patients (25 women, 81 men; mean age: 45.4 12.3 years) were included in this prospective comparative clinical study. Patients in the non-operative arm (n = 42) received standardised physiotherapy. Patients in the surgical arm (n = 38) underwent arthroscopic subacromial decompression. All patients were followed up at 3, 6 and 12 months. Shoulder function (Constant score), pain (Numerical Rating Scale), and the duration of inability to work were assessed. RESULTS Shoulder function and pain improved significantly with both kinds of treatment. At no time of follow up we detected significant differences between the two treatment options. An analysis of the patients' ability to work showed that conservative treatment was superior to surgical treatment at 3-month follow-up (0.3 versus 5.0 weeks; p < 0.001) and between 4 and 6-month after intervention (0.2 versus 1.6 weeks; p = 0.032). DISCUSSION In the study presented here, significant improvements in function (Constant score) and pain (NRS) were achieved in both the non-operative and the surgical arm. There were no significant differences between the two groups at any time point. These results are similar to those reported by other authors in recent studies. Unlike other research work, however, our study demonstrated a major difference in the development and duration of inability to work. CONCLUSIONS Conservative and surgical treatment of subacromial impingement syndrome led to similar outcomes for shoulder pain and function at 3, 6 and 12 months after intervention. However, patients who were managed conservatively returned to work significantly earlier than patients who underwent surgery. Key words: subacromial impingement, shoulder, constant score, pain, ability to work.

[Premature wear of total knee arthroplasty in sports shown in a golfer]. / Vorzeitiger Verschleiß von Knieendoprothesen im Sport am Beispiel eines Golfers.

Sport with an endoprosthesis is controversially discussed, whereas golf with a knee endoprosthesis is usually allowed. This case shows that playing golf can lead to severe wear of the prosthesis. The wear pattern of the components of the prosthesis suggests increased rotational loads. A change to a constrained prosthesis was made because of metal-to-metal contact. It is important to inform the patient before surgery about sports with endoprosthesis. Athletic loads are not part of prosthesis testing according to ISO.

Deactivation of cardiovascular implantable electronic devices in patients nearing end of life : Reality or only recommendation?

BACKGROUND: Current guidelines recommend considering deactivation of cardiac implantable electronic devices (CIEDs) in patients nearing death. We evaluated the implementation of this recommendation in unselected deceased individuals with CIEDs. METHODS: Over a 7-month period in 2016, all deceased persons taken to the Rostock crematorium were prospectively screened for CIEDs and these were interrogated in situ. Pacing rate, pacing mode, and lead output were documented as well as patient data including location and time of death. In implantable cardioverter-defibrillators (ICDs), tachycardia therapy adjustment and occurrence of shocks 24 h prior to death were also recorded. RESULTS: We examined 2297 subjects, of whom 154 (6.7%) had CIEDs. Of these subjects, 125 (100%) pacemakers (PMs) and 27 (96.4%) ICDs were eligible for analysis. Death in persons with ICDs occurred most frequently in hospital (55.6%), while this was less frequently the case for individuals with PMs (43.2%). Furthermore, 33.3% of subjects with ICDs and 18.5% with PMs died in palliative care units (PCU). Shock therapies were switched off in three (60%) individuals with ICDs who died in the PCU, whereas antibradycardia therapy was not withdrawn in any PM patient in the PCU. Therapy withdrawal occurred in two patients with PMs (1.3%) who died in hospital. Patients with PMs had high ventricular pacing rates at the last interrogation (69 ± 36.0%) and often suffered atrioventricular block (39.2%). Six (25%) of the 24 active ICDs presented shocks near the time of death. CONCLUSION: Many CIED patients died in hospital; nonetheless, in practice, CIED deactivation near death is rarely performed and might be less feasible in subjects with PMs. However, there is still a need to consider deactivation, especially in individuals with ICDs, as one fourth of them received at least one shock within 24 h prior to death.

[Osteotomies around the knee for ligament insufficiency]. / Kniegelenknahe Osteotomien bei Bandinsuffizienzen.

BACKGROUND: The osseous geometry of the lower limb has a significant impact on knee instability after ligament injuries, and osseous malalignment has been shown to be a significant risk factor for the failure of ligament reconstruction procedures. Therefore, osteotomies around the knee have gained importance as a combined or isolated treatment option in the ligament deficient and malaligned knee. In addition to unloading of an arthritic knee compartment, osteotomies are also performed to protect a reconstructed ligament and to stabilize the joint without ligament surgery. PROCEDURE: In addition to the correction of varus or valgus malalignment, correction of sagittal imbalance by modifying the tibial slope is an emerging concept. Even small modifications of the tibial slope (≤5°) have been shown to change the anterior-posterior translation in a clinically significant manner. Especially in the case of chronic posterior or posterolateral instability, a valgus-producing and slope-increasing high tibial osteotomy is usually the first treatment option, and ligament surgery is only performed optionally. Isolated modification of the tibial slope is performed infrequently, however, a slope-decreasing osteotomy should be considered in patients with multiple failed ACL reconstructions and a tibial slope of >12°.

Stem cells and bFGF in tendon healing: Effects of lentiviral gene transfer and long-term follow-up in a rat Achilles tendon defect model.

BACKGROUND: The influence of stem cells and lentiviral expression of basic fibroblastic growth factor (bFGF) on tendon healing and remodelling was investigated in an in-vivo long-term (12 weeks) rat Achilles tendon defect model. METHODS: In sixty male Lewis rats, complete tendon defects (2.4 mm) were created and either left untreated (PBS) or treated by injection of stem cells lentivirally expressing the enhanced green fluorescence marker gene eGFP (MSC-LV-eGFP) or basic fibroblast growth factor bFGF (MSC-LV-bFGF). Tendons were harvested after 12 weeks and underwent biomechanical and (immuno)-histological analysis. RESULTS: After 12 weeks the mean ultimate load to failure ratio (treated side to contralateral side) in biomechanical testing reached 97 % in the bFGF-group, 103 % in the eGFP-group and 112 % in the PBS-group. Also in the stiffness testing both MSC groups did not reach the results of the PBS group. Histologically, the MSC groups did not show better results than the control group. There were clusters of ossifications found in all groups. In immunohistology, only the staining collagen-type-I was strongly increased in both MSC groups in comparison to PBS control group. However, there were no significant differences in the (immuno)-histological results between both stem cell groups. CONCLUSION: The biomechanical and (immuno)-histological results did not show positive effects of the MSC groups on tendon remodelling in a long-term follow-up. Interestingly, in later stages stem cells had hardly any effects on biomechanical results. This study inspires a critical and reflected use of stem cells in tendon healing.

[Biomaterials in orthopedics]. / Biomaterialien in der Orthopädie.

Biomaterials are artificial or natural materials, which are used in living organisms for a wide variety of reasons. Currently, there are biomaterials available for practically all types of tissue and can fulfill temporary and permanent functions. Ideally, materials used for temporary roles should be completely resorbed after the fulfilling the function and those with a permanent role should remain stable within the body. Many of the currently available biomaterials do not possess these optimal features. Those with temporary roles often remain unchanged within the organism or only induce an incomplete regeneration and those with permanent roles suffer biological alterations which reduce the function. Despite the enormous number of biomaterials, it must always be considered whether the therapeutic target can be achieved without using an implant.

Adjunctive surgical atrial fibrillation ablation during cardiac surgery: real life experiences.

AIM: Several tools have been invented for surgical atrial fibrillation (AF) ablation. In this study, we investigated the real world efficacy of intraoperative AF ablation (AFA) with radiofrequency-energy or cryo-ablation and performed an electro-anatomical remap in some patients with recurrences. METHODS: Seventy-three consecutive patients (53 male, median age of 69 ± 7 years) with history of AF underwent cardiac surgery for valve repair (74 % mitral defects, 60 % aortic defects) and/or coronary artery bypass graft procedures (56 %). During a follow-up of 23 ± 11 months after AFA we performed intensified holter-monitoring (4-7 days). Patients with symptomatic relapse of atrial arrhythmias (AA) were offered the opportunity for additional electrophysiological examination (EPE). RESULTS: During 23 ± 11 months after AFA, 45 patients (62 %) had recurrent AA. In eight patients we performed EPE. In all 8 cases, septal circumferential lesions could be demonstrated during mapping with discrete gaps. All lateral veins were isolated however, posteriorly deep inside the vein leaving the antral region completely untreated. Neither roof lines nor mitral isthmus lines were complete. Performing catheter ablation, all veins could be isolated and seven patients were free of any arrhythmias during follow up (9 ± 5 months) without taking antiarrhythmic drugs. CONCLUSION: Surgical AF ablation may often be incomplete rendering sobering results in unselected patients. Completion of the ablation is feasible with catheter ablation with good clinical outcome.

[The German Cartilage Registry (KnorpelRegister DGOU) for evaluation of surgical treatment for cartilage defects: experience after six months including first demographic data]. / Das KnorpelRegister DGOU zur Erfassung von Behandlungsergebnissen nach Knorpeloperationen: Erfahrungen nach 6 Monaten und erste epidemiologische Daten.

The German Cartilage Registry (KnorpelRegister DGOU) has been introduced in October 2013 and aims on the evaluation of patients who underwent cartilage repair for symptomatic cartilage defects. It represents a nation-wide cohort study which has been introduced by the working group "Tissue Regeneration" of the Germany Society of Orthopaedic Surgery and Traumatology and is technically based upon a web-based remote data entry (RDE) system. The present article describes first experiences with the registry including patient and treatment characteristics. Between October 2013 and April 2014, a total of 230 patients who had undergone surgical cartilage repair for symptomatic full-thickness cartilage defects of the knee has been included in the German Cartilage Registry from 23 cartilage repair centres. Mean age was 37.11 years (SD 13.61) and mean defect size was 3.68 cm(2) (SD 0.23). Since the introduction of the KnorpelRegister DGOU the total number of registered patients has increased steadily up to the most recent figure of 72 patients within one month. Patients were treated mainly according to the recommended therapies. The highest percentage in therapy is represented by the bone marrow stimulation techniques (55.02 %) as well as by the autologous chondrocyte transplantation (34.92 %). Unlike the patient collective in the majority of prospective randomised controlled trials, the patient population within the registry shows a high proportion of patients with accompanying pathologies, with an age of more than 50 years at the time of treatment and with unfavourably assessed accompanying pathologies such as an affection of the opposite cartilage surface or a previously resected meniscus. In summary, the technical platform and forms of documentation of the KnorpelRegister DGOU have proved to be very promising within the first six months. Unlike data from other clinical trials, the previous analysis of the patients' data and therapies reflects successfully the actual medical care situation of patients with cartilage defects of the knee joint. This analysis also provides new information on subgroups of patients that have not yet been recorded in the scientific literature. This will be part of the first analysis of clinical treatment data. An expansion of the KnorpelRegister DGOU to patients with cartilage defects of the ankle and hip joints is already decided upon and initialised.

[Arthroscopic resection of the acromioclavicular joint]. / Arthroskopische Resektion des Akromioklavikulargelenks.

OBJECTIVE: Arthroscopic resection of the painful and degenerative altered acromioclavicular (AC) joint without destabilization of the joint and therefore pain relief and improvement in function. INDICATIONS: Conservative failed therapy of painful AC joint osteoarthritis. Impingement caused by caudal AC joint osteophytes. Lateral clavicular osteolysis. CONTRAINDICATIONS: General contraindications (infection, local tumor, coagulation disorders), higher grade instability of the AC joint (resection only together with stabilization). SURGICAL TECHNIQUE: Diagnostic glenohumeral arthroscopy. Treatment of accompanying lesions (subacromial impingement, rotator cuff, long head of biceps). Subacromial arthroscopy with bursectomy (partial) and visualization of the AC joint. Resection of caudal osteophytes. Localization of the anterior portal using a spinal needle in the outside-in technique. Resection of 2-3 mm of the acromial side and the 3-4 mm of the clavicular side with shaver/acromionizer. RESULTS: An isolated open AC joint resection was performed in 9 studies and an arthroscopic resection in 6 studies. Good and very good results were obtained in 79% (range 54-100%) in open resection and 91% (range 85-100%) in arthroscopic resections. Patients were able to return to activities of daily life more quickly after arthroscopic resections than after open surgery.

Stem cells and basic fibroblast growth factor failed to improve tendon healing: an in vivo study using lentiviral gene transfer in a rat model.

BACKGROUND: The aim of this controlled study was to investigate the influence of mesenchymal stem cells (MSCs) and lentiviral (LV) expression of basic fibroblast growth factor (bFGF) on tendon remodeling in an in vivo rat model of an Achilles tendon defect. METHODS: In eighty-four male Lewis rats, complete 2.4-mm tendon defects were created and were either left untreated (the phosphate-buffered saline solution [PBS] group) or were treated with mesenchymal stem cells expressing enhanced green fluorescent protein (the MSC-LV-eGFP group) or with mesenchymal stem cells expressing basic fibroblast growth factor lentivirally (the MSC-LV-bFGF group). After fourteen and twenty-eight days, the tendons were harvested and analyzed biomechanically and immunohistologically. RESULTS: After fourteen days, both mesenchymal stem cell groups were slightly superior in biomechanical testing. However, only the PBS control group showed a significant increase in biomechanical results over time (fourteen versus twenty-eight days; p = 0.012). Biomechanical results were better after twenty-eight days for the control group than for both MSC groups. However, the difference was significant only with regard to the stiffness results in the comparison of the PBS control and the eGFP stem cell group (p = 0.024). Histologically, the MSC groups had no better results than the control group after fourteen and twenty-eight days. In immunohistology, only labeling for type-I procollagen was strongly increased in both MSC groups in comparison with the PBS control group (p = 0.0009 for the MSC-LV-bFGF group and p = 0.0041 for the MSC-LV-eGFP group at fourteen days, and p = 0.004 and p = 0.132, respectively, at twenty-eight days). There were no significant differences in the immunohistological results between the stem cell groups. CONCLUSIONS: The biomechanical and immunohistological results showed that mesenchymal stem cells in both groups had only partially positive effects on tendon remodeling in the initial stages; however, in later stages, stem cells had potentially negative effects on biomechanical results. The additional expression of bFGF in stem cells had negligible effects on tendon remodeling. CLINICAL RELEVANCE: Preliminary studies using stem cells are partially promising; however, there are no relevant clinical data showing that stem cells are of significant benefit. The present study should lead to a more critical evaluation and thoughtful use of stem cells in humans until more clinical data are available.

[Conservative therapy of osteoarthritis]. / Konservative Therapie der Gonarthrose.

Osteoarthritis of the knee is a degenerative joint disease with progressive degradation of articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking and joint effusion depending on the stage of the disease. In an effort to delay major surgery, patients with knee osteoarthritis are offered a variety of nonsurgical modalities, such as weight loss, exercise, physiotherapy, bracing, orthoses, nonsteroidal anti-inflammatory drugs (NSAIDs) and intra-articular viscosupplementation or corticosteroid injection. In general, the goals of these therapeutic options are to decrease pain and improve function. Some of these modalities may also have a disease-modifying effect by altering the mechanical environment of the knee. Chondroprotective substances, such as lucosamine, chondroitin sulphate and hyaluronic acid are safe and provide short-term symptomatic relief while the therapeutic effects remain uncertain.

[Arthroscopically assisted therapy of avascular necrosis of the femoral head]. / Arthroskopisch gestützte Behandlung der aseptischen Hüftkopfnekrose.

OBJECTIVE: Preservation of the hip joint function by treatment of the avascular necrosis of the femoral head in adults or at least avoiding progression. INDICATIONS: Avascular necrosis of the femoral head in adults in Steinberg stages I-III. In patients with Steinberg stage IVa (subchondral collapse ≤ 15% of the articular surface, depression < 2 mm) hip joint salvage therapy in early stages of femoral head collapse. CONTRAINDICATIONS: Manifest osteoarthritis of the hip joint. Joint infection. Relative contraindications: subchondral collapse > 15% of the articular surface or depression > 2 mm (Steinberg stage IVb and above). Persisting risk factors for a progression of avascular necrosis (e.g., alcohol abuse, chemotherapy, local irradiation, high-dose cortisone therapy) and obesity (BMI > 40). SURGICAL TECHNIQUE: Arthroscopy of the hip joint in case of cartilage defects and/or potential collapse of the femoral head. Without collapse of the femoral head and absence of severe damage of the cartilage: core decompression using a guiding sleeve through a lateral approach (Steinberg II, III). Subsequently curettage of the necrotic area through a central drill hole and insertion of autogenic bone cylinders using an OATS harvester (Steinberg II b/c, III b/c). In Steinberg stage IVa, reconstruction of the outline of the femoral head is attempted by reduction of the impressed portion (under intraoperative fluoroscopy). POSTOPERATIVE MANAGEMENT: Limited weight bearing (10 kg) of the operated leg for 6 weeks. In cases of large necrotic defects located directly beneath the subchondral bone (Steinberg IIIc) as well as subchondral collapse with flattening of the femoral head (Steinberg IVa) limited weight bearing (10 kg) for 12 weeks. RESULTS: Early results of femoral head preserving therapy in 53 patients (56 hips, consecutively treated between June 2004 and December 2009) after 33 ± 20 months: success rate (no arthroplasty, no reoperation, no radiological progress associated with clinical symptoms) 86% for patients treated with Steinberg stages I-III. Failure of the head preserving therapy with concern to the mentioned criteria depending on the initial Steinberg stage: 0 (0%) for stage I, 2 (10%) for stage II, 3 (25%) for stage III, and 4 (31%) for stage IVa.

[Calcific tendinitis of the shoulder]. / Die Kalkschulter - Tendinosis calcarea.

Calcific tendinitis of the shoulder is a process involving crystal calcium deposition in the rotator cuff tendons, which mainly affects patients between 30 and 50 years of age. The etiology is still a matter of dispute. The diagnosis is made by history and physical examination with specific attention to radiologic and sonographic evidence of calcific deposits. Patients usually describe specific radiation of the pain to the lateral proximal forearm, with tenderness even at rest and during the night. Nonoperative management including rest, nonsteroidal anti-inflammatory drugs, subacromial corticosteroid injections, and shock wave therapy is still the treatment of choice. Nonoperative treatment is successful in up to 90% of patients. When nonsurgical measures fail, surgical removal of the calcific deposit may be indicated. Arthroscopic treatment provides excellent results in more than 90% of patients. The recovery process is very time consuming and may take up to several months in some cases.

Biomechanics of the goat three bundle anterior cruciate ligament.

The goat is a widely used animal model for basic research on the anterior cruciate ligament (ACL), but the biomechanical role of the different bundles [intermediate (IM), anteromedial (AM), posterolateral (PL)] of the ACL is unclear. Therefore, the aim of this study is to describe the biomechanical function of the different bundles and evaluate its use for a double bundle ACL reconstruction model. A CASPAR Stäubli RX90 robot with a six degree-of-freedom load cell was used for measurement of anterior tibial translation (ATT) (mm) and in situ forces (N) at 30 degrees (full extension), 60 degrees , 90 degrees as well as rotational testing at 30 degrees in 14 paired goat knees before and after each bundle was cut. When the AM-bundle was cut, the ATT increased significantly at 60 degrees and 90 degrees of flexion (p < 0.05). When the PL-bundle was cut, the ATT increased only at 30 degrees. However, most load was transferred through the big AM-bundle while the PL-bundle shared significant load only at 30 degrees, with only minimal contribution from the IM-bundle at all flexion degrees. The observed biomechanical results in this study are similar to the human ACL observed previously in the literature. Though anatomically discernible, the IM-bundle plays only an inferior role in ATT and might be neglected as a separate bundle during reconstruction. The goat ACL shows some differences to the human ACL, whereas the main functions of the ACL bundles are similar.

[Arthroscopic ventral shoulder stabilization]. / Die arthroskopische ventrale Schulterstabilisierung.

Traumatic antero-inferior dislocation of the shoulder is a common injury among the young athletic population. The incidence of reluxation after conservative treatment in young patients is up to 80%. Arthroscopic antero-inferior shoulder stabilization has become the gold standard in recent years due to technical and material improvement. The recurrence rate after arthroscopic and open surgery is similar (approximately 6.5%), but morbidity after arthroscopic surgery is less. The authors of this paper advise the use of suture anchors for refixation of the capsulolabral complex. An antero-inferior approach is used for ideal positioning of the anchors on the glenoid rim and lesions of the superior biceps tendon or other co-morbidities can be addressed at the same time. In conclusion arthroscopic shoulder stabilization is an appropriate treatment for antero-inferior shoulder dislocation.

The structure of the coracoacromial ligament: fibrocartilage differentiation does not necessarily mean pathology.

The coracoacromial ligament forms part of the coracoacromial arch and is implicated in impingement syndrome and acromial spur formation. Here, we describe its structure and the composition of its extracellular matrix. Ligaments were obtained from 15 cadavers, nine from older people (average age 74.7 years) and six from younger individuals (average age 24.2 years). Cryosections of methanol-fixed tissue were cut and sections were immunolabelled with monoclonal antibodies against collagens, glycosaminoglycans, proteoglycans, matrix proteins and neurofilament proteins. Both ligament entheses were highly fibrocartilaginous and immunolabelled strongly for type II collagen, aggrecan and link protein. The area of labelling was more extensive in older people. However, fibrocartilage also characterized the ligament midsubstance, particularly with increased age. Signs of fibrocartilage degeneration were more common in older people. Ligament fat (containing blood vessels and nerve fibers) was conspicuous in both age groups, especially between fiber bundles at the entheses. We conclude that fibrocartilage is a normal feature but becomes more pronounced with age. It is not necessarily pathological, for it simply indicates that the ligament is subject to compression and/or shear. Nevertheless, the prominence of fibrocartilage at the acromial enthesis may relate to the frequency with which enthesophytes develop.

[3D-Culturing of human osteoblastic cells with vessel like nutrient supply]. / 3D-Kultivierung humaner osteoblastärer Zellen unter gefässähnlicher Nährstoffversorgung.

AIM: The treatment of large, critical-size bone defects is a major therapeutic problem in orthopaedic and reconstructive surgery. The engineering of bone tissue could be used to replace lost bone mass. However, scaffolds seeded with vital cells and cultured in vitro suffer from poor oxygen and nutrient supply centrally, when the constructs exceed a critical volume. Therefore, we have established an osteoblastic cell culture in a new 3D-culture chamber with an artificial, vessel-like central membrane, allowing continuous nutrient supply. METHOD: Human osteoblasts were cultured in a 3D-like manner using a perfusion chamber for one week. In this system, the nutrient supply is guaranteed by a vessel-like, semipermeable polysulfone membrane with a continuous flow of medium. After fixation and cryosectioning, histological and immunohistological staining and scanning electron microscopy was carried out. RESULTS: Examinations reveal 3D cell growth around the central vessel. Formation of an extracellular matrix, rich in collagen type I and fibronectin, was detected immunohistochemically. Furthermore, we demonstrated cell adherence to the membrane and examined the surface morphology by scanning electron microscopy. CONCLUSION: The innovative approach for 3D-culturing of human osteoblasts in a system with a central nutrient supply opens up new possibilities for the in vitro cultivation for tissue engineering.

[Anatomy of the superior labrum complex of the shoulder]. / Die Anatomie des oberen Labrumkomplexes im Schultergelenk.

The outstanding progress achieved in MRI and arthroscopic techniques has forced orthopedic surgeons to consider the anatomy of the shoulder joint in detail. The superior labrum complex shows a broad range of variations, which is the reason for some difficulties regarding diagnostic conclusions as well as therapeutic considerations. In particular, the differentiation between the normal and pathological adherence of the labrum is a serious clinical problem. The glenoid labrum consists of circularly arranged collagenous fibers attached to the osseous margin of the glenoid by a fibrocartilaginous transitional zone. The cranial part of the labrum is more compact than the caudal one. It is also connected to the joint capsule and the integrated ligaments. Most of the fibers of the long head of the biceps tendon insert at the supraglenoid tubercle, only some of them continue in the fibrous ring. So-called SLAP lesions have to be differentiated from variations. In up to 18% of the patients normal clefts can be seen, e. g., sublabral holes, and in less than 6% other rare variations, e. g., the so-called Buford complex.