Gelatin-based haemostyptic Spongostan as a possible three-dimensional scaffold for a chondrocyte matrix?: an experimental study with bovine chondrocytes.

The gelatin-based haemostyptic compound Spongostan was tested as a three-dimensional (3D) chondrocyte matrix in an in vitro model for autologous chondrocyte transplantation using cells harvested from bovine knees. In a control experiment of monolayer cultures, the proliferation or de-differentiation of bovine chondrocytes was either not or only marginally influenced by the presence of Spongostan (0.3 mg/ml). In monolayers and 3-D Minusheet culture chambers, the cartilage-specific differentiation markers aggrecan and type-II collagen were ubiquitously present in a cell-associated fashion and in the pericellular matrix. The Minusheet cultures usually showed a markedly higher mRNA expression than monolayer cultures irrespective of whether Spongostan had been present or not during culture. Although the de-differentiation marker type-I collagen was also present, the ratio of type-I to type-II collagen or aggrecan to type-I collagen remained higher in Minusheet 3-D cultures than in monolayer cultures irrespective of whether Spongostan had been included in or excluded from the monolayer cultures. The concentration of GAG in Minusheet cultures reached its maximum after 14 days with a mean of 0.83 +/- 0.8 microg/10(6) cells; mean +/-, SEM, but remained considerably lower than in monolayer cultures with/without Spongostan. Our results suggest that Spongostan is in principle suitable as a 3-D chondrocyte matrix, as demonstrated in Minusheet chambers, in particular for a culture period of 14 days. Clinically, differentiating effects on chondrocytes, simple handling and optimal formability may render Spongostan an attractive 3-D scaffold for autologous chondrocyte transplantation.

[Development of a catalogue of undergraduate learning objectives for orthopaedics and traumatology]. / Entwicklung des Lernzielkatalogs "Muskuloskelettale Erkrankungen, Verletzungen und traumatische Notfälle" für Orthopädie-Unfallchirurgie im Medizinstudium.

BACKGROUND: The development towards a combined speciality of orthopaedic and trauma surgery requires not only consolidation and revision of the postgraduate education training programme but also the development of a catalogue of learning objectives as a uniform basis for undergraduate medical training in the new speciality at German medical schools and teaching hospitals. MATERIALS AND METHODS: Based on the Frankfurt catalogue of learning objectives for trauma surgery and the Ulm catalogue of learning objectives for orthopaedics, a task force of experts developed a combined catalogue of learning objectives for the new speciality. Experts from both specialities classified the learning objectives into two levels of knowledge and four grades of skills competence, in addition to objectives for attitudes and social competence. RESULTS: The section on general operative specialities contains 120 items classified into 39 learning objectives for knowledge and 83 for skills. Two learning objectives comprise both knowledge and skills. The section on orthopaedic and trauma surgery comprises 141 learning objectives, including six items for skills and 138 for knowledge, as well as three learning objectives for both knowledge and skills. In addition, 22 learning objectives deal with aspects of attitude and social competence. CONCLUSION: Although this alliance of orthopaedics and trauma surgery is recent, the commission has developed not only a collection of topics but a joint catalogue of learning objectives for undergraduate training that can be used nationwide. This catalogue paves the way for modern education that looks to the future. The integrated recommendations for content prioritisation, links to other subjects and specialities, and the integration of didactic methods facilitate local implementation of the learning objectives without loss of academic freedom.

[Development of a catalogue of undergraduate learning objectives for orthopaedics and traumatology]. / Entwicklung des Lernzielkatalogs "Muskuloskeletale Erkrankungen, Verletzungen und traumatische Notfälle" für Orthopädie--Unfallchirurgie im Medizinstudium.

BACKGROUND: The developments towards a combined specialty of orthopaedic and trauma surgery requires not only the consolidation and revision of the postgraduate education training programme but also the development of a catalogue of learning objectives as a uniform basis for undergraduate medical training in the new specialty at German medical schools and teaching hospitals. MATERIALS AND METHODS: Based on the Frankfurt Catalogue of Learning Objectives for Trauma Surgery and the Ulm Catalogue of Learning Objectives for Orthopaedics, a task force of experts has developed a combined catalogue of learning objectives for the new specialty. The experts of both specialties classified the learning objectives into 2 levels for knowledge, into 4 grades of competence for skills, as well as attitudes and social competence. RESULTS: The general part of the operative specialties contains 120 items classified into 39 learning objectives for knowledge and 83 for skills. Two learning objectives comprise both knowledge and skill. The part orthopaedic and trauma surgery comprises 141 learning objectives, six items for skills, 138 for knowledge, as well as three learning objectives for both knowledge and skills. In addition, 22 learning objectives deal with aspects of attitudes and social competence. CONCLUSION: In spite of the only recent alliance of orthopaedics and trauma surgery, the commission has developed not only a collection of topics, but also a usable joint catalogue of learning objectives for undergraduate training with a nationwide recommendation character. The catalogue paves the way for a forward-looking, modern education. The integrated recommendations for the prioritisation, the linkage to other subjects and specialties, and the integration of didactic methods facilitate the local implementation of the learning objectives without loosing any academic freedom.

[Autologous chondrocyte transplantation in the ankle joint. Rational or irrational?]. / Autologe Chondrozytentransplantation am oberen Sprunggelenk. Rational oder irrational?

Ankle sprains are one the most common injuries of the lower limb. Fractures, ligamentous lesions, and cartilaginous damage are often associated. Nevertheless the injury is often misjudged and concomitant chondral lesions are assessed late. In the case of a symptomatic osteocartilaginous lesion of the talus, which can be illustrated by MRI or X-ray, operative intervention is indicated. Methods such as microfracturing, mosaicplasty, and autologous chondrocyte transplantation (ACT) are in clinical use. The latter is well known and being established as the treatment of choice for large cartilage defects in the knee. Due to the good results in the knee and the technological improvements (three-dimensional tissue constructs seeded with autologous chondrocytes) this method is being increasingly applied for cartilage lesions of the talus. In contrast to the mosaicplasty donor site morbidity is low and the size of the defect is not a limiting factor. The current studies about ACT of the talus show a stable repair of the defect with mostly hyaline-like cartilage and high patient satisfaction. Therefore, the procedure can be recommended for lesions>1 cm2. Concomitant treatment of posttraumatic deformities (malalignment), ligamentous instabilities, and especially the reconstruction of bony defects are compulsory.

Proprioceptive skills and functional outcome after anterior cruciate ligament reconstruction with a bone-tendon-bone graft.

Several studies have shown that patients with anterior cruciate ligament (ACL) reconstruction have an improved proprioceptive function compared to subjects with ACL-deficient knees. The measurement of functional scores and proprioception potentially provides clinicians with more information on the status of the ACL-reconstructed knees. To evaluate proprioception in patients following ACL reconstruction with a bone-tendon-bone (BTB) graft, we used the angle reproduction in the sitting, lying and standing positions and the one-leg hop test. Forty-five patients between 19 and 52 years of age were investigated in a 36-month period after the operation. For functional performance measurement, the International Knee Documentation Committee (IKDC) score was used. Very good and good results were seen in 95% of cases. All patients returned to the same activity level as seen before ACL repair. There was a significant difference in the active angle reproduction test between the ACL-reconstructed knees and normal knees in the active sitting position. Tests with passive angle adjustment in the sitting, lying and active standing positions did not show any differences in proprioceptive skills. Good to very good results in the one-leg hop test we found in 95% of patients. After ACL reconstruction, deficiencies in the active angle reproduction test were very small but, nevertheless, were still observed. Overall, the functional and proprioceptive outcomes demonstrate results to recommend the procedure.

[Radiological and clinical functional examinations 36 months after anterior cruciate ligament repair by a patellar tendon graft]. / Radiologische und klinisch funktionelle Untersuchung 36 Monate nach vorderer Kreuzbandplastik mittels Patellarsehnentransplantat.

AIM: The aim of this study was to examine radiological and functional outcome measurements after anterior cruciate ligament (ACL) reconstruction with a bone-tendon-bone (BTB) graft. Investigations included assessment of bony integration conditions regarding the use of bioabsorbable cross pins or a lateral screw for femoral graft fixation. A description of radiological parameters in contrast with IKDC findings is also given. METHOD: After ACL injuries, 45 patients underwent an ACL repair. For tibial tunnel placement the tibial guide was used in full knee extension. A size-specific femoral aimer was placed by using the transtibial technique in the "over the top" position and the tunnel was reamed with the acorn reamer to 30 mm depth. In 15 patients the BTB graft was fixed with a titanium blunt nose screw from the lateral aspect. The cross-pin technique with bioabsorbable RIGIDFIX implants was used in 30 patients. All patients underwent a follow-up study 36 month postoperatively. Geometric tests of digitised X-rays were performed. For clinical and functional outcome studies of ACL repairs the IKDC score is widely accepted. The score was modified into numeric parameters for 15 selected groups of the IKDC score. All 15 categories were rated from 1 to 4 points (Category A = 4, B = 3, C = 2, D = 1). Clinical and radiological results were statistically analysed. RESULTS: According to the literature, tunnel placement tibial was physiological in 91% and femoral in 93% of the cases. The femoral tunnel was completely invisible in all patients. No necrosis or pathological findings in former pin holes were seen. In 24 patients the medial compartment space was smaller, but less than 50 % compared to intraoperative X-rays. Even if the mean of tibial tunnel widening was 2.65 mm it was statistically not connected to the results of the IKDC score or X-ray findings of the femoral tunnel. Results in the IKDC groups and categories were seen to be in accord with overall very good and good outcomes. The modified IKDC score showed a mean of 55 points with a range from 46 as lowest (1 patient) and 60 in 4 patients (9%) as highest numeric score. CONCLUSION: Lateral femoral fixation with screws or bioabsorbable cross-pins shows a biological bony incorporation of a BTB graft. Tibial tunnel widening was seen but without any functional effects. Overall radiological and functional outcomes based on the IKDC score demonstrate results in favour of ACL reconstruction with BTB grafts. Due to the narrowing of the medial compartment space, more radiological outcome studies with a special emphasis on degenerative aspects have to be done.

[Intra-articular pain during gonarthrosis: a case report about an extremely increased cathepsin expression in chondrocytes]. / Intraartikulärer Schmerz bei Gonarthrose: Ein Fallbericht über eine stark erhöhte Expression der Cathepsine in Chondrozyten.

AIM AND BACKGROUND: Cysteine proteases as cathepsins K and L as well as matrix metalloproteases are considered to be basically involved in collagen turnover. Degenerative joint diseases such as gonarthrosis are characterised by massive cartilage degradation mediated by increased activities of these proteases. These enzymes are, therefore, interesting targets for the treatment of painful arthritic joint diseases. The aim of these studies was to reconsider the hypothesis that cathepsin activities are enhanced in patients suffering from osteoarthritis. METHOD AND RESULTS: We report on a 69-year-old female suffering from severe pain due to predominant retropatellar arthrosis. The clinical symptoms of this patient did not significantly differ from that of 30 other patients who were involved in this study. All patients undergone an endoprosthetic knee joint replacement. During the operation we harvested cartilage probes and isolated the chondrocytes from the joint cartilage for determination of the mRNA and the activities of cathepsins B, H, K and L. Compared to chondrocytes isolated from the control patients we found the activity of cysteine proteases to be extremely enhanced in chondrocytes of this patient. Moreover, the concentration of cystatin c, an endogenous inhibitor of cathepsins, was not detectable. CONCLUSION: The results raise doubts on the predominant role of cysteine proteases in severe cartilage destruction.

[The subacromial impingement syndrome]. / Das subakromiale Impingementsyndrom.

The subacromial impingement syndrome describes the pathological contact between the rotatory cuff and the acromion. It is only a symptom and not a generic term for the different pathological diseases of the subacromial region. It is the diagnostical aim to verify the pathogenesis of the impingement syndromes and it is essential to differentiate structural versus functional causes. The diagnosis "impingement syndrome" should not have an acromioplastic procedure as general consequence. Because the expression "impingement syndrome" does not show causal approach it should no longer be used as a diagnosis. The term subacromial syndrome, in conjunction with the underlying pathological cause, acquires more therapeutic and prognostic clarity.

[Transgluteal mini-incision. Technique and our own results]. / Transgluteale Miniinzision : Technik und eigene Resultate.

BACKGROUND: A transgluteal mini-incision technique according to the approach of Bauer et al. is described. MATERIAL AND METHODS: Altogether 194 patients were supplied with a cementless primary total hip endoprosthesis using this approach. Our own results regarding ASA, body mass index, operation time, transfusions, the course of the Hb values, and the use of drugs against pain are described. RESULTS: The approach does not show any dependence on ASA and BMI. Operation time, blood loss, and use of drugs against pain are not influenced by it. Angled reamers and impactors are mandatory to prevent additional damage of soft tissue. The cosmetic benefit seems to be the only advantage. The approach cannot be recommended for general use.

Press fit fixation of cementless cups: how much stability do we need indeed?

INTRODUCTION: Using screws for a better primary and secondary fixation has been discussed in the literature of the recent years, although the principle of press fit has been explained as the principle of a push-button. The authors wanted to compare their own results in patients using X-rays from the postoperative course to decide if it is really safer to use screws or not. MATERIALS AND METHODS: Two hundred and twenty one consecutive, not selected patients were treated with total hip arthroplasty using a cementless cup type Duraloc. They were followed up over a time of 5 years for radiological changes of the bony acetabulum around the cup ("acetabular zones" according to De Lee and Charnley). One hundred and ten cups were additionally fixed with one to three screws at the upper part in region C1, 101 cups were implanted without the use of screws. RESULTS: Periprosthetic changes visible on the radiographs (immediate postoperative gaps, subsequent sclerosis and radiolucent lines) were assessed according to the time of their appearance. A gap in zone C2 was seen more often immediately after operation within the group without screws (17.8% vs. 7.3%) and disappeared within the following 25 months. Within the group with screws significantly more often a gap was found in zone C1 and C3 compared to the group without screws (7.3% vs. 1.9%). In the group with screws a sclerosis of the bone in zone C1 developed in 32.7% mostly within the first 5 months. It was followed by a radiolucent line in zone C3 in 28.2% mainly within 5-25 months postoperatively and in zone C1 in 20.9% within 16 months. Significantly less seldom were these phenomena seen at the cups without screw fixation. There was no correlation between lateral or medial positioning and deviations from the ideal inclination to the bony changes around the cups. No signs of loosening occurred in either group. CONCLUSION: Less radiological changes around the cup if no screws were used and no disadvantages within this group led to the conclusion that an additional screw fixation in principle is not necessary in press-fit cups.

Osteointegration of hydroxyapatite-titanium implants coated with nonglycosylated recombinant human bone morphogenetic protein-2 (BMP-2) in aged sheep.

Osteointegration of metal implants into aged organisms can be severely compromised due to reduced healing capacity of bone, lack of precursor cells for new bone formation, or osteoporosis. Here, we report on successful implant healing in a novel model of aged sheep in the presence of nonglycosylated bone morphogenetic protein 2 (BMP-2). Ewes of 8 to 12 years with significant radiologic and histologic signs of osteoporosis and adipocytic bone marrow received a cylindrical hydroxyapatite-titanium implant of 12 x 10 mm. BMP-2 has been produced as a bacterial recombinant fusion protein with maltose-binding protein and in vitro generation of mature BMP-2 by renaturation and proteolytic cleavage. A BMP-2 inhibition ELISA was developed to measure the in vitro release kinetics of bioactive human BMP-2 from immersed solid implant materials by using Escherichia coli expressed and biotinylated recombinant human BMP-2 receptor IA extracellular domain (ALK-3 ECD). The implants were placed laterally below both tibial plateaus, with the left leg implant carrying 380 microg BMP-2. Both implant types became integrated within the following 20 weeks. The control implant only integrated at the cortical bone, and little new bone formation was found within the pre-existing trabecular bone or the marrow cavity. Marrow fat tissue was partially replaced by unspecific connective tissue. In contrast, BMP-2-coated implants initiated significant new bone formation, initially in trabecular arrangements to be replaced by cortical-like bone after 20 weeks. The new bone was oriented towards the cylinder. Highly viable bone marrow appeared and filled the lacunar structures of the new bone. In mechanical tests, the BMP-2-coated implants displayed in average 50% higher stability. This animal model provided first evidence that application of nonglycosylated BMP-2 coated on solid implants may foster bone healing and regeneration even in aged-compromised individuals.

[Metatarsalgia. Differential diagnosis and therapeutic algorithm]. / Metatarsalgie. Differenzialdiagnose und Therapie.

Metatarsalgia is explained as localized or more diffuse tenderness beneath the metatarsal heads. The pain may be attributed to various etiologies. Pathological changes affecting the positional relationship of the metatarsals in the sagittal plane can cause increased pressure and friction forces during weight bearing. Since the length of the metatarsals displays a wide range of disparity only a few pathological settings, i.e., brachymetatarsia, require surgical correction. Beside those disorders of positional relationship, metatarsalgia may be due to lesser toe deformities, osteonecrosis of a lesser metatarsal head (Koehler's disease), and neurological disorders (Morton's neuroma). Apart from the etiology increased load, which is transferred to the central metatarsals, can be treated successfully with orthotic devices. If conservative measures fail, surgical treatment can be indicated. Prior to any operative therapy it is mandatory to perform a detailed analysis of the underlying pathology to avoid persistent pain or recurrence of the deformity.

[The acquired buckling-flatfoot. A foot deformity due to obesity?]. / Der erworbene Knick-Plattfuss Eine Fussdeformität des Ubergewichtigen?

Flatfoot deformity is characterized by a multiplanar hindfoot malalignment. Although the etiology remains unclear, the deformity is mainly attributed to ligamentous laxity and dysfunction of the posterior tibial tendon. Obesity is thought to be a risk factor that additionally impairs hindfoot stability. Performing a retrospective clinical and radiological study, we compared two groups, each with 75 patients. One group included patients with a flatfoot deformity stage 2, while the other group showed no hindfoot malalignment. Reviewing the weight and calculating the body mass index revealed significantly increased values for those patients with flatfoot deformity (P=0.034 and P>0.001, respectively). This correlation should be considered during the decision-making process on surgical strategies. In obese patients with flatfoot deformity, stage 2 soft tissue reconstruction and hindfoot osteotomies should be combined with hindfoot arthrodeses, i.e. subtalar fusion, to maintain sufficient and durable stability.

[Periprosthetic bone loss after total hip endoprosthesis. Dependence on the type of prosthesis and preoperative bone configuration]. / Verlauf der periprothetischen Knochendichte nach Hüfttotalendoprothesenimplantation. Abhängigkeit von Prothesentyp und knöcherner Ausgangssituation.

The changes of the periprosthetic bone density were examined with DEXA in 81 patients over a period of 1 year after implantation of cementless total hip endoprosthesis. Four types of endoprostheses (Vision 2000/Duraloc, ALPHA-Fit/ALPHA-Lock Plus, CLS/Allofit, Mayo/Trilogy) were implanted. Information on the changes of the periprosthetic bone density depending on the type of the prosthesis and the bony situation at the femur before operation was expected from these measurements. In all types of stems the strongest reduction of the bone density was found in the region of the calcar femoris, and the smallest changes were found distally and medially of the tip of the prostheses. In the prosthesis with shorter stem the change of the bone density was altogether clearly lower than in prostheses with longer stem. With increasing size of the prosthesis with proximally porous coating made from cobalt-chrome alloy, proximal atrophy was observed more frequently, whilst in the prosthesis made from titanium alloy with completely rough-blasted surface the distal hypertrophy increased. A low preoperative corticalis-bone marrow index strengthened the proximal atrophy in proximally porously coated prosthesis made from cobalt-chrome alloy and led in the prosthesis with completely rough-blasted surface more often to distal hypertrophy of the bone.

[5-year follow-up study of total knee arthroplasty by means of EMG mapping]. / Nachuntersuchungsergebnisse mittels EMG-Mapping - 5 Jahre nach Knieendoprothesenimplantation.

AIM: The objective of the present study was to evaluate the long-term functional results after implantation of a total knee arthroplasty (TKA) objectively and quantitatively. METHOD: Functional parameters (muscular coordination, strength and range of motion) and the subjective satisfaction of the patients were measured by means of EMG mapping, isokinetics, ultrasound and a questionnaire in 21 patients with TKA 5.1 years after implantation of the TKA. RESULTS: 81 % of the investigated patients were subjectively satisfied. The isokinetic results showed a significant improvement of the extensor strength and of the relation between flexors and extensors. Patients who had been more physically active over these 5 years reached significantly better results. The results of EMG mapping showed good overall retention of the satisfactory coordination levels resulting from the initial in-patient rehabilitation. But the coordination patterns demonstrated clear changes showing highly activated areas in the region of the M. vastus medialis. The range of motion and the contraction capacity showed no further improvement compared with the results 26 weeks after implantation of the TKA. CONCLUSION: Long-term results after implantation of a TKA showed a good muscular coordination, strength and range of motion. A higher physical activity level led to better functional results and greater overall satisfaction of TKA patients 5 years after implantation.

Effect of bupivacaine application on cholinesterase activities, total protein- and albumin concentration in serum and cerebrospinal fluid.

The rationale of this study was to determine whether Bupivacaine used for spinal anesthesia alters the specific secretory activity of nerve cells and/or the function of the blood/cerebrospinal fluid barrier. Four groups were assessed: (1) patients undergoing spinal anesthesia using Bupivacaine for lower limb surgery, (2) spinal Bupivacaine anesthesia without subsequent surgery, (3) local facet joint infiltration using Bupivacaine, and (4) general anesthesia for lower limb surgery without Bupivacaine application. Cholinesterase activities, total protein- and albumin concentrations in serum as well as in cerebrospinal fluid were significantly decreased after surgical intervention under spinal Bupivacaine anesthesia but remained unchanged following spinal Bupivacaine application without surgery. No significant correlation was found between Bupivacaine dosage and parameter alteration. There was no influence of intrathecal Bupivacaine application on the albumin ratio cerebrospinal fluid/serum, nor was there any significant alteration of total protein- or albumin concentrations and butyrylcholinesterase activity in the serum as a result of local injection of Bupivacaine to facet joints. These serum parameters were reduced after surgery under general anesthesia. Alterations of serum- and cerebrospinal fluid parameters investigated after surgery are not related to Bupivacaine application but to effects linked to operative treatment, i.e. suppressed secretory cell activity or protein depletion owing to blood loss. We conclude that the secretory function of cholinesterase-releasing nerve cells is not affected by spinal application of Bupivacaine. The blood/cerebrospinal fluid barrier remains intact.

Acetylcholinesterase assay for cerebrospinal fluid using bupivacaine to inhibit butyrylcholinesterase.

BACKGROUND: Most test systems for acetylcholinesterase activity (E.C.3.1.1.7.) are using toxic inhibitors (BW284c51 and iso-OMPA) to distinguish the enzyme from butyrylcholinesterase (E.C.3.1.1.8.) which occurs simultaneously in the cerebrospinal fluid. Applying Ellman's colorimetric method, we were looking for a non-toxic inhibitor to restrain butyrylcholinesterase activity. Based on results of previous in vitro studies bupivacaine emerged to be a suitable inhibitor. RESULTS: Pharmacokinetic investigations with purified cholinesterases have shown maximum inhibition of butyrylcholinesterase activity and minimal interference with acetylcholinesterase activity at bupivacaine final concentrations between 0.1 and 0.5 mmol/l. Based on detailed analysis of pharmacokinetic data we developed three equations representing enzyme inhibition at bupivacaine concentrations of 0.1, 0.2 and 0.5 mmol/l. These equations allow us to calculate the acetylcholinesterase activity in solutions containing both cholinesterases utilizing the extinction differences measured spectrophotometrically in samples with and without bupivacaine. The accuracy of the bupivacaine-inhibition test could be confirmed by investigations on solutions of both purified cholinesterases and on samples of human cerebrospinal fluid. If butyrylcholinesterase activity has to be assessed simultaneously an independent test using butyrylthiocholine iodide as substrate (final concentration 5 mmol/l) has to be conducted. CONCLUSIONS: The bupivacaine-inhibition test is a reliable method using spectrophotometrical techniques to measure acetylcholinesterase activity in cerebrospinal fluid. It avoids the use of toxic inhibitors for differentiation of acetylcholinesterase from butyrylcholinesterase in fluids containing both enzymes. Our investigations suggest that bupivacaine concentrations of 0.1, 0.2 or 0.5 mmol/l can be applied with the same effect using 1 mmol/l acetylthiocholine iodide as substrate.

Salvage of the upper extremity in cases of tumorous destruction of the proximal humerus.

Malignant bone tumours or metastasis of the upper humerus may cause significant loss of function especially in those patients with resectional arthroplasty of the shoulder. One method for achieving functional reconstruction of the humerus concerned is replacement with a modular endoprosthesis. Little is known about clinical and radiological results in these rare circumstances. Between 1993 and 1997 we treated 21 patients (22 shoulders) with enlarged osteolytic destructions of the proximal humerus caused by metastatic spread or primary malignant tumours. Patients with additional involvement of the glenoid were excluded from this study. The average follow-up was 3.9 years. Every 3 months all patients were followed-up clinically and radiographically. Prior to surgery, diagnosis was established by incisional biopsy and the outcome determined the therapeutic algorithm (radiotherapy, chemotherapy, surgery). In most cases of metastatic lesions, surgery was the first treatment. According to the regional spread of the tumour, various amount of bone and soft tissues had to be removed. The distal stem of the prosthesis was inserted in a cementless way and secured to bone with two interlocking screws. The length of the diaphyseal part depended on the site of osteotomy. Soft-tissue coverage of the large implant was achieved in all patients. Early complications were lymphogenic oedema and superficial wound dehiscence. One patient developed a deep infection, which had to be managed surgically. According to the functional rating system of the Musculoskeletal Tumour Society for the upper extremity the overall results were inversely proportional to the extent of resection. None of our patients achieved unrestricted motion of the shoulder concerned. The most important finding was a proximal migration of the prosthesis causing a painful subacromial impingement, mainly a consequence of the resection of the deltoid muscle and the rotator cuff. In summary, a modular endoprosthesis cannot be recommended generally as the method of choice. If the muscular balance of the shoulder is too weak to act as a joint centralizer the endoprosthesis has no advantage over a simple diaphyseal spacer.

[Complications and therapy after arthroscopic interventions of the knee joint]. / Komplikationen und deren Therapie nach arthroskopischen Eingriffen am Kniegelenk.

Complications following arthroscopic knee surgery are known from the literature to be relatively rare. It hence is all the more important for the rehabilitation staff to know the possible risks for complications. Usually it is quite sufficient to perform a good clinical examination in case of complications in order to be able to carry out the necessary therapeutic measures in regular contact with the surgeons involved. Among the most dangerous complications requiring immediate therapy are the extraarticular vascular complication, the knee joint infection, and the intraarticular bleeding complication. Responsible teamwork among surgeons and rehabilitation staff will be the key to a successful treatment outcome.