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During three 'Polarstern' cruises to the ice-covered Greenland Sea (spring 1997, summer 1994, autumn 1995) studies on the under-ice habitat (morphology, hydrography, ice-algal biomass) and on the macrofaunal, autochthonous under-ice amphipods (species diversity, abundance) were carried out in order to describe environmental controls and seasonal patterns in this community. In spring, the ice underside was rather smooth and whitish, while in summer melting structures and sloughed-off ice-algal threads were observed, in autumn detritus clumps accumulated in depressions at the ice underside. Only in summer, a thin layer of warm (up to -0.6 [degrees] C) and less saline (as low as S = 6.3) water was found at the ice-water interface above Polar Water. Integrated ice-algal biomass was highest during autumn (2.6 mg chl a [m.sup.-2]) and lowest during summer (1.2 mg chl a [m.sup.-2]). Four species of under-ice amphipods occurred in spring and summer (Apherusa glacialis, Onisimus glacialis, O. nanseni, Gammarus wilkitzkii), but only the last species was observed at the ice underside in autumn. A. glacialis and G. wilkitzkii were equally abundant in spring; A. glacialis dominated in summer. The highest total abundance of amphipods occurred during summer (31.9 ind. [m.sup.-2]), compared to lower abundances in spring and autumn (5.3 and 1.1 ind. [m.sup.-2], respectively). A factor analysis revealed seasonal patterns in the data set, which mainly influences. A. glacialis, and species-specific relations between several environmental factors and the distribution of under-ice amphipods. Abundance of A. glacialis was closely related to the under-ice hydrography and ice-legal biomass, whereas the other amphipod species were more influenced by the under-ice morphology. It is therefore stated that the observed thinning of the Arctic sea ice and the resulting increased meltwater input and change in morphology of floes will have a profoundly adverse effect on the under-ice amphipods.

The vertical distribution of algal communities found in marine sea ice in the central Arctic and the Greenland Sea is reported. Using algal pigments and cell counts from the surface, the interior and the bottom layer of ice floes, it was shown that pennate diatoms dominate the bottom layer, while phototrophic flagellates and cysts dominate the upper parts. Differences between the results and previously reported data from other coastal locations suggest that there are several biological regimes in Arctic sea ice.

Objective: Treatment of tumors of the pelvic girdle by resection of part or all of the innominate bone with preservation of the extremity. Implantation and stable fixation using a custom-made megaprosthesis to restore painless joint function and loading capacity. The surgical goal is to obtain a wide surgical margin and local tumor control., Indications: Primary bone and soft tissue sarcomas, benign or semi-malignant aggressive lesions, metastatic disease (radiation resistance and/or good prognosis)., Contraindications: Limited life expectancy and poor physical status, extensive metastatic disease, persistent deep infection or recalcitrant osteomyelitis, poor therapeutic compliance, local recurrence following a previous limb-sparing resection, extensive infiltration of the neurovascular structures and the intra- and extrapelvic soft tissues., Surgical Technique: Levels of osteotomy are defined preoperatively by a CT-controlled manufactured three-dimensional 1:1 model of the pelvis. Using these data, the custom-made prosthesis and osteotomy templates are then constructed by the manufacturer. The anterior (internal, retroperitoneal) and posterior (extrapelvic, retrogluteal) aspects of the pelvis are exposed using the utilitarian incision surgical approach. The external iliac and femoral vessels are mobilized as they cross the superior pubic ramus. The adductor muscles, the rectus femoris and sartorius muscle are released from their insertions on the pelvis and the obturator vessels and nerve are transected. If the tumor extends to the hip joint, the femur is transected at a level distal to the intertrochanteric line to ensure hip joint integrity and to prevent tumor contamination. A large myocutaneous flap with the gluteus maximus muscle is retracted posteriorly. The pelvitrochanteric and small gluteal muscles are divided near their insertion in the upper border of the femur. To release the hamstrings and the attachment of the sacrotuberous ligament, the ischial tuberosity is exposed. After osteotomy using the prefabricated templates, the pelvis is released and the specimen is removed en bloc. The custom made prosthesis can either be fixed to the remaining iliac bone or to the massa lateralis of the sacrum. The released muscles are refixated on the remaining bone or the implant., Postoperative Management: Time of mobilization and degree of weight-bearing depends on the extent of muscle resection. Usually partial loading of the operated limb with 10 kg for a period of 6-12 weeks, then increased loading with 10 kg per week. Thrombosis prophylaxis until full weight bearing. Physiotherapy and gait training. At follow-up, patients are monitored for local recurrence and metastases using history, physical examination, and radiographic studies., Results: Between 1994 and 2008, 38 consecutive patients with periacetabular tumors were treated by resection and reconstruction with a custom-made pelvic megaprosthesis. The overall survival of the patients was 58% at 5 years and 30% at 10 years. One or more operative revisions were performed in 52.6% of the patients. The rate of local recurrence was 15.8%. Deep infection (21%) was the most common reason for revision. In two of these cases (5.3%), a secondary external hemipelvectomy had to be performed. There were four cases of aseptic loosening (10.5%) in which the prosthesis had to be revised. Six patients had recurrent hip dislocation (15.8%). In four of them a modification of the inserted inlay and an implantation of a trevira tube had to be performed respectively. Peroneal palsy occurred in 6 patients (15.8%) with recovery in only two. There were 4 operative interventions because of postoperative bleeding (10.5%). The mean MSTS score for 12 of the 18 living patients was 43.7%. In particular, gait was classified as poor and almost all patients were reliant on walking aids. However, most patients showed good emotional acceptance.

Objective: Management of primary or secondary acetabular bone loss (D'Antonio type I-IV ). Implantation and stable fixation using a cementless, cranially extended oval press-fit cup to restore painless joint function and loading capacity., Indications: Septic or aseptic loosening of the acetabular component after total hip arthroplasty. Acetabular bone loss after tumor resection. Primary acetabular bone defects in developmental dysplasia of the hip., Contraindications: Persistent deep infection. Bone defects including the parts of the iliac bone adjoining the sacrum (fixation of the stem in the ilium is not possible any more)., Surgical Technique: Complete exposure of the acetabular defect using a standard approach. Removal of the loose cup. Excision of soft and granulation tissue from the acetabular ground and the rim. Reaming of the acetabulum with sequentially larger hemispheric reamers until an adequate bony bed is created for the insertion of the cranial socket. Eccentric cranial sockets without a craniolateral flap are preferable for use in type I and II defects with teardrop lysis mostly involving the craniolateral acetabulum, if a trihedral press-fit fixation can be achieved. Supplementary screw fixation through the acetabular ground, is possible. If a type III defect is present, the authors recommend the use of cranial sockets with an anatomic flap in order to increase primary stability by supplementary screw fixation. This is especially recommended for the management of deficiencies in the medial or posterior wall. If there is pelvic discontinuity (type IV), adequate acetabular reconstruction with primary stability of the component can only be achieved by a supplementary intramedullary structured stem fixed in the dorsal part of the ilium., Postoperative Management: Partial loading of the operated limb with 10 kg for a period of 6-12 weeks. Then increased loading with 10 kg per week. Thrombosis prophylaxis until full weight bearing. Physiotherapy and gait training., Results: A total of 50 cup revisions using the ESKA cranial socket system were clinically and radiologically analyzed with an average follow-up of 65.7+/-28.5 months (26-123 months). Defects were classified according to D'Antonio. There were 21 type II, 23 type III, and six type IV defects. The Harris Hip Score increased from 40 preoperatively to 68.3 points postoperatively. Four patients had recurrent hip dislocation requiring replacement of the inlay. In four cases of aseptic loosening, the acetabular component had to be revised. With revision of the acetabular component as an endpoint, implant survival was 92% after an average of 5.4 years.

A number of drugs can have "side effects" on bone metabolism and formation, causing bone atrophy, impaired mineralisation, as well as osteonecrosis. In both clinical and general practitioner settings, these forms of bone damage have been hitherto considered as adverse drug side effects and have received insufficient attention; moreover, they have not been the subject of patient information. Preventive measures are not instigated prior to initiation of medication and even after onset of bone damage, therapeutic strategies are poorly implemented. Even fracture healing with its complex, staged course can be both positively and negatively influenced by a number of drugs and these effects require monitoring. Recommendations regarding practical screening and therapy of drug-induced osteopathies are presented.

Photosynthetic parameters of phytoplankton and sea ice algae from landfast sea ice of the Chukchi Sea off Point Barrow, Alaska, were assessed in spring 2005 and winter through spring 2006 using Pulse Amplitude Modulated (PAM) fluorometry including estimates of maximum quantum efficiency (F(v)/F(m)), maximum relative electron transport rate (rETR(max)), photosynthetic efficiency (alpha), and the photoadaptive index (E(k)). The use of centrifuged brine samples allowed to document vertical gradients in ice algal acclimation with 5 cm vertical resolution for the first time. Bottom ice algae (0-5 cm from ice-water interface) expressed low F(v)/F(m) (0.331-0.426) and low alpha (0.098-0.130 (micromol photons m(-2)s(-1))(-1)) in December. F(v)/F(m) and alpha increased in March and May (0.468-0.588 and 0.141-0.438 (micromol photons m(-2)s(-1))(-1), respectively) indicating increased photosynthetic activity. In addition, increases in rETR(max) (3.3-16.4 a.u.) and E(k) (20-88 micromol photons m(-2) s(-1)) from December to May illustrates a higher potential for primary productivity as communities become better acclimated to under-ice light conditions. In conclusion,photosynthetic performance by ice algae (as assessed by PAM fluorometry) was tightly linked to sea ice salinity, temperature, and inorganic nutrient concentrations (mainly nitrogen).

Upper and plantar heel pains are differentiated from one another. Plantar heel pain is usually caused by plantar fasciitis. A heel spur is a side effect and is not related to the cause of the symptoms. Upper heel pain is mostly caused by tendonitis of the Achilles tendon or Haglund exostosis. Only through an exact diagnosis is an adequate and usually conservative therapy possible. If the conservative therapy should fail, it is nevertheless important to clarify the indication for surgery to prevent the problems from becoming chronic.

The family physician can provide his patient with useful information to help him decide in favor of or against a total hip replacement procedure. This also applies to the choice of the most suitable endoprosthetic system, such pre-operative measures as discontinuation or change of medication, and the assessment of possible perioperative or postoperative complications.

Injuries seen in football players mainly affect the knee and ankle joints and muscles. The causes include chronic overstrain and traumatization usually resulting from physical contact between opponent players. Torsional trauma of the joints results in excessive stressing of the capsular ligaments, potentially leading to rupture of the structures involved. Therapeutic options range from conservative measures to reconstructive or prosthetic surgery. While muscular injuries have a good prognosis with regard to the chances of continuing sports activities, injuries to ligaments often enforce a lengthy pause from sports. Extensive injuries to cartilages can terminate a player's sporting career. However, new procedures that take account of physiological biomechanics, together with the further development of surgical technologies now often allow players to regain their pre-injury level of fitness. Specific rehabilitation is a major therapeutic means of preventing further injury.

On account of the considerable variability of the clinical situation, treatment of soft tissue sarcoma requires an individually oriented multimodal approach. In the case of patients with superficial low-grade tumors measuring less than 5 cm in diameter, resection alone is usually adequate. In the event of medium-grade lesions, resection with negative margins, resection in combination with radiotherapy achieves excellent local control rates associated with an overall survival rate of almost 80%. In patients with high-grade sarcomas measuring more than 5 cm in diameter, local control can be achieved with resection and radiotherapy, although every second such patient develops metastases. For patients with local recurrence, further resection should be considered/performed. Radiotherapy is all the more effective, the smaller the postoperative tumor cell burden.

Owing to the relatively high incidence of this condition (2 in 1,000 neonates) and the poor functional outcome of inadequate treatment, clubfoot represents a major clinical problem. Although its etiology is not fully known, modern three-dimensional analyses have led to a better understanding of the pathomorphology and provide a new basis for a differentiated therapeutic strategy. Of central importance is early diagnosis and immediate postpartum initiation of primarily conservative treatment taking the form of intensive redressment measures. Depending on the residual deformity, an appropriate surgical procedure aimed at achieving complete correction should be done between the age of 4 to 6 months. To ensure a lasting positive outcome, rigorous follow-up physiotherapeutic treatment and close surveillance are essential.