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The SoLid experiment aims to measure neutrino oscillation at a baseline of 6.4 m from the BR2 nuclear reactor in Belgium. Anti-neutrinos interact via inverse beta decay (IBD), resulting in a positron and neutron signal that are correlated in time and space. The detector operates in a surface building, with modest shielding, and relies on extremely efficient online rejection of backgrounds in order to identify these interactions. A novel detector design has been developed using 12800 5 cm cubes for high segmentation. Each cube is formed of a sandwich of two scintillators, PVT and 6LiF:ZnS(Ag), allowing the detection and identification of positrons and neutrons respectively. The active volume of the detector is an array of cubes measuring 80× 80× 250 cm (corresponding to a fiducial mass of 1.6 T), which is read out in layers using two dimensional arrays of wavelength shifting fibres and silicon photomultipliers, for a total of 3200 readout channels. Signals are recorded with 14 bit resolution, and at 40 MHz sampling frequency, for a total raw data rate of over 2 Tbit/s. In this paper, we describe a novel readout and trigger system built for the experiment, that satisfies requirements on: compactness, low power, high performance, and very low cost per channel. The system uses a combination of high price-performance FPGAs with a gigabit Ethernet based readout system, and its total power consumption is under 1 kW. The use of zero suppression techniques, combined with pulse shape discrimination trigger algorithms to detect neutrons, results in an online data reduction factor of around 10000. The neutron trigger is combined with a large per-channel history time buffer, allowing for unbiased positron detection. The system was commissioned in late 2017, with successful physics data taking established in early 2018. The SoLid experiment aims to measure neutrino oscillation at a baseline of 6.4 m from the BR2 nuclear reactor in Belgium. Anti-neutrinos interact via inverse beta decay (IBD), resulting in a positron and neutron signal that are correlated in time and space. The detector operates in a surface building, with modest shielding, and relies on extremely efficient online rejection of backgrounds in order to identify these interactions. A novel detector design has been developed using 12800 5 cm cubes for high segmentation. Each cube is formed of a sandwich of two scintillators, PVT and 6LiF:ZnS(Ag), allowing the detection and identification of positrons and neutrons respectively. The active volume of the detector is an array of cubes measuring 80x80x250 cm (corresponding to a fiducial mass of 1.6 T), which is read out in layers using two dimensional arrays of wavelength shifting fibres and silicon photomultipliers, for a total of 3200 readout channels. Signals are recorded with 14 bit resolution, and at 40 MHz sampling frequency, for a total raw data rate of over 2 Tbit/s. In this paper, we describe a novel readout and trigger system built for the experiment, that satisfies requirements on: compactness, low power, high performance, and very low cost per channel. The system uses a combination of high price-performance FPGAs with a gigabit Ethernet based readout system, and its total power consumption is under 1 kW. The use of zero suppression techniques, combined with pulse shape discrimination trigger algorithms to detect neutrons, results in an online data reduction factor of around 10000. The neutron trigger is combined with a large per-channel history time buffer, allowing for unbiased positron detection. The system was commissioned in late 2017, with successful physics data taking established in early 2018.

The SoLid experiment has been designed to search for an oscillation pattern induced by a light sterile neutrino state, utilising the BR2 reactor of SCK$\bullet$CEN, in Belgium. The detector leverages a new hybrid technology, utilising two distinct scintillators in a cubic array, creating a highly segmented detector volume. A combination of 5 cm cubic polyvinyltoluene cells, with $^6$LiF:ZnS(Ag) sheets on two faces of each cube, facilitate reconstruction of the neutrino signals. % The polyvinyltoluene scintillator is used as an $\overline{\nu}_e$ target for the inverse beta decay of ($\overline{\nu}_e + p \rightarrow e^{+}+n$), with the $^6$LiF:ZnS(Ag) sheets used for associated neutron detection. Scintillation signals are read out by a network of wavelength shifting fibres connected to multipixel photon counters. Whilst the high granularity provides a powerful toolset to discriminate backgrounds; by itself the segmentation also represents a challenge in terms of homogeneity and calibration, for a consistent detector response. The search for this light sterile neutrino implies a sensitivity to distortions of around $\mathcal{O}$(10)\% in the energy spectrum of reactor $\overline{\nu}_e$. Hence, a very good neutron detection efficiency, light yield and homogeneous detector response are critical for data validation. The minimal requirements for the SoLid physics program are a light yield and a neutron detection efficiency larger than 40 PA/MeV/cube and 50 \% respectively. In order to guarantee these minimal requirements, the collaboration developed a rigorous quality assurance process for all 12800 cubic cells of the detector. To carry out the quality assurance process, an automated calibration system called CALIPSO was designed and constructed., Comment: Submitted to JINST

This paper presents a comprehensive optimisation study to maximise the light collection efficiency of scintillating cube elements used in the SoLid detector. Very short baseline reactor experiments, like SoLid, look for active to sterile neutrino oscillation signatures in the anti-neutrino energy spectrum as a function of the distance to the core and energy. Performing a precise search requires high light yield of the scintillating elements and uniformity of the response in the detector volume. The SoLid experiment uses an innovative hybrid technology with two different scintillators: polyvinyltoluene scintillator cubes and $^6$LiF:ZnS(Ag) screens. A precision test bench based on a $^{207}$Bi calibration source has been developed to study improvements on the energy resolution and uniformity of the prompt scintillation signal of antineutrino interactions. A trigger system selecting the 1~MeV conversion electrons provides a Gaussian energy peak and allows for precise comparisons of the different detector configurations that were considered to improve the SoLid detector light collection. The light collection efficiency is influenced by the choice of wrapping material, the position of the $^6$LiF:ZnS(Ag) screen, the type of fibre, the number of optical fibres and the type of mirror at the end of the fibre. This study shows that large gains in light collection efficiency are possible compared to the SoLid SM1 prototype. The light yield for the SoLid detector is expected to be at least 52$\pm$2 photo-avalanches per MeV per cube, with a relative non-uniformity of 6 %, demonstrating that the required energy resolution of at least 14 % at 1 MeV can be achieved., 25 pages, 19 figures, published in JINST 2018_JINST_13_P09005

The SoLid collaboration has developed a new detector technology to detect electron anti-neutrinos at close proximity to the Belgian BR2 reactor at surface level. A 288$\,$kg prototype detector was deployed in 2015 and collected data during the operational period of the reactor and during reactor shut-down. Dedicated calibration campaigns were also performed with gamma and neutron sources. This paper describes the construction of the prototype detector with a high control on its proton content and the stability of its operation over a period of several months after deployment at the BR2 reactor site. All detector cells provide sufficient light yields to achieve a target energy resolution of better than 20%/$\sqrt{E(MeV)}$. The capability of the detector to track muons is exploited to equalize the light response of a large number of channels to a precision of 3% and to demonstrate the stability of the energy scale over time. Particle identification based on pulse-shape discrimination is demonstrated with calibration sources. Despite a lower neutron detection efficiency due to triggering constraints, the main backgrounds at the reactor site were determined and taken into account in the shielding strategy for the main experiment. The results obtained with this prototype proved essential in the design optimization of the final detector. This paper is dedicated to our SCK$\cdot$CEN colleague, Edgar Koonen, who passed away unexpectedly in 2017. Edgar was part of the SoLid collaboration since its inception and his efforts were vital to get the experiment started. He will be duly missed., 29 pages, 23 figures, submitted to JINST

Spondylodiscitis is a severe infectious disease of the intervertebral discs and of the adjacent parts of the vertebral bodies, culminating in destruction of the mobile segment. It is accompanied by a mortality rate of approximately 15%. Severe courses of the disease can also lead to abscess formation and dispersal of sepsis. Malpositioning of the axis organ and deficits in neurological function up to paraplegia are also possible complications. Timely diagnostics and targeted therapy contribute to minimizing the risk of significant health disorders. This review article gives a summary of important algorithms in the diagnostics and treatment and discusses them against the background of currently available literature. According to the current state of knowledge the surgical treatment of spondylodiscitis provides many advantages and is therefore the method choice, even if a conservative approach can be successful in selected cases. The endpoints of treatment are cleansing of the infection with normalization of laboratory parameters of inflammation and the osseous fusion of the mobile segment.

The next generation of very-short-baseline reactor experiments will require compact detectors operating at surface level and close to a nuclear reactor. This paper presents a new detector concept based on a composite solid scintillator technology. The detector target uses cubes of polyvinyltoluene interleaved with $^6$LiF:ZnS(Ag) phosphor screens to detect the products of the inverse beta decay reaction. A multi-tonne detector system built from these individual cells can provide precise localisation of scintillation signals, making efficient use of the detector volume. Monte Carlo simulations indicate that a neutron capture efficiency of over 70% is achievable with a sufficient number of $^6$LiF:ZnS(Ag) screens per cube and that an appropriate segmentation enables a measurement of the positron energy which is not limited by gamma-ray leakage. First measurements of a single cell indicate that a very good neutron-gamma discrimination and high neutron detection efficiency can be obtained with adequate triggering techniques. The light yield from positron signals has been measured, showing that an energy resolution of 14%/$\sqrt{E({\mathrm{MeV}})}$ is achievable with high uniformity. A preliminary neutrino signal analysis has been developed, using selection criteria for pulse shape, energy, time structure and energy spatial distribution and showing that an antineutrino efficiency of 40% can be achieved. It also shows that the fine segmentation of the detector can be used to significantly decrease both correlated and accidental backgrounds., 17 pages, 15 figures, submitted to JINST

103 patients with 106 Muller straight stem prostheses could be evaluated clinically and radiologically after an average follow-up period of 6.8 years (range 5 to 10 ys.). Although until now no revision for aseptic loosening has become necessary 3 p.c. of the stems and 11 p.c. of the acetabular components showed radiological loosening. The clinical results were rated as satisfactory. After surgery 67 p.c. of the patients were completely painfree, 28 p.c. still had slight pain, 4 p.c. moderate and 1 p.c. severe pain. The investigation concentrated particularly on radiographic changes of the interface of the femur. Whereas radiolucency typically was non-progressive and located in the proximal part of the femur we found an increasing atrophy of the cortical bone on the calcar. Moreover, we found a continuous and increasing subsidence of the stem during the whole period of observation. At the time of follow up 56 p.c. of the straight stems had subsided about 2 mm and more. Calcar atrophy and radiolucency were significantly less present in femurs with a tapered medullary canal than in those with a cylindrical shape.

27 cemented stems were implanted in fresh-frozen human cadaver femora with third generation antegrade cementing technique and with prechilled vacuum-mixed and pre-pressurized Palacos R bone cement. 3 groups with different implantation techniques were compared according to the achieved cement mantle thickness distribution. Group 1 (modified stem fixation): 7 canulated stems inserted over guidetubes that were fixed in distal synthetic plugs (3 Willert CF-30 and 4 flanged Charnley stems). The guidetubes served simultaneously for stem centralization and evacuation of the intramedullary cavity. Group 2: 12 stems with distal centralizers with fins (4 flanged Charnley, 8 anatomic cemented AC), and Group 3: 8 stems without centralizer (4 Willert CF-30 and 4 flanged Charnley). For analysis, each femur was cut into mean 25 cross-sections (range, 22 - 31). Contact radiographs were taken and digitized with a sampling distance of 0,12mm (204.8 dpi). Using a custommade computer program (FemStat 1.001), the cement mantle thickness was determined at mean 650 implant surface points per cross section. Results: The percentage of critical cement mantle thickness was lower for the canulated stems with guidetube. Here 14.1% of the measurements were smaller than 2mm. For the stems with distal centralizer and without centralizer this was 28.3% and 28.2% (p = 0.003 and p = 0.002, U-test). Cement mantles smaller than 1mm were also reduced for group 1 (2.8% compared with 4.7% and 7.5%) but this was not significant (p = 0.384 and p = 0.094). The stems without centralizers had only slightly inferior cement mantles if compared to stems with distal centralizers with fins (for < 2mm p = 0.571, for < 1mm p = 0.305). Comparing different cementing techniques for one constant type of prosthesis (Charnley) the canulated stems with guide tubes provided a significantly better cement mantle thickness than the stems with distal centralizers (for < 2mm 10.3% compared with 26.6%, p = 0.029; for < 1mm 1.5% compared with 3.4%, p = 0.343). Distal centralizers failed, as the intramedullary cavity is elliptic in cross section and the gaps between the wings caused malposition. For all stems in group 3 improvement of the cement mantle thickness was predominantly achieved in the distal and middle third of the femur. Conclusion: The implantation technique with canulated stems inserted over a guidetube allows superior stem positioning leading to a more favourable cement mantle.

The equipment available for rehabilitation of patients with joint conditions still lacks a device that, in common with usual physiotherapeutic measures (manipulation, proprioceptive neuromuscular facilitation, Bobath therapy), is based on traction and/or compression or oscillating forms. The novel "Shoulder Rotator" is such a simple device for the variable treatment of shoulder disorders in all three spatial dimensions. After individual instruction, the patient performs rotating glenohumeral exercises with simultaneous glenohumeral joint traction, compression, or oscillations against static or dynamic resistance. The "Shoulder Rotator" is similar to the established continuous passive motion device for the shoulder and is mounted on a mobile chair. The electronic device control is computerised and permits a wide variety of treatment options, individual regimes, and documentation. The oscillating, compression/distraction mode of operation provides an analgesic effect. The isolated compression mode along the rotatory axis enables conditioning of joint proprioception. The distraction mode along the rotatory axis facilitates muscular relaxation. Resistive rotatory exercises strengthen the rotatory glenohumeral muscles and help centre the humeral head in the glenoid. In addition to the advantage of adding documentation of treatment progress as required for evidence-based medicine, this novel device may bring about a cost-effective, genuine quality improvement in shoulder rehabilitation.

We describe the mid-term clinical results of the surgical treatment of primary degenerative arthritis of the sternoclavicular joint in eight women. They had not responded to conservative treatment and underwent a limited resection arthroplasty. For pre-and postoperative clinical evaluation we used the Rockwood score for the sternoclavicular joint. Postoperatively, the Constant score was also determined. The mean follow-up was 31 months (10 to 82). The median Rockwood score increased from 6 to 12.5 points. The median postoperative Constant score was 87 (65 to 91). Four patients had an excellent, three a good, and one a poor result. All patients were pleased with the cosmetic result. Resection arthroplasty is an effective and safe treatment for chronic, symptomatic degenerative arthritis of the sternoclavicular joint with a high degree of patient satisfaction.

This paper presents the results of histologic studies conducted in the context of tenosynovectomy of the flexor tendons to treat carpal tunnel syndrome. The most common findings were inflammatory changes of the synovial sheath, vascular pathology and fibrous changes of the connective tissue.

In this paper the kinematics of arm abduction in the scapular plane of 38 healthy experimental subjects is reported. The ratio of the glenohumoral and the scapulothoracic components of the motion were determined and the influence of the abduction speed and of the external load on it were investigated. The investigation of the effect of abduction speed involved all 38 subjects. Each of them performed one slow and one fast abduction. Statistical analysis showed that there were large differences between individuals, but that for any one individual the abduction process is essentially reproducible. For the one individual there is a strong, linear relationship between glenohumeral and scapulothoracic rotation. The slope of the regression of the glenohumeral component on total arm abduction varied from 0.75 to 0.5 with a sample mean of 0.66. It means that only two-thirds of arm abduction occurs in the glenohumeral joint, the remaining third taking place via scapular rotation. In slowly performed abductions the slope of the regression was significantly greater than in the high-speed movements, but differences were very small. In the investigation of the effect of external load, statistical analysis indicated that the slope of the intraindividual regression is largely independent of the load. The possibility of observer bias was analysed, too. It was found that the standard deviation of the abduction parameters determined by different observers was between 6 and 10% of that between different experimental subjects. RELEVANCE: A knowledge of the kinematics of the shoulder joint is necessary to understand subacromial pathology and in particular impingement problems. The scapulohumeral rhythm depends on the balanced and coordinated function of the muscles involved. The activation pattern of the abductor muscles, as reflected in shoulder kinematics, seems to be individual and stored as an engram.

The radiation exposure during biomechanical investigation of the shoulder joint done with a digital radiography system (Polytron 1000 VR - Siemens) was measured experimentally. Total radiation dose and surface dose were determined by phantom measurements. The radiation exposure per image is about 1/6 to 1/7 of that of a conventional study. The digital radiography system used is thus suitable for kinesiologic studies of large joints in healthy volunteers.

A series of 90 patients, 85 males and 5 females, all with ACL-ruptures had a follow up between 5 and 12 years. All of them had a primary arthrotomy with or without meniscectomy but in no case an operative repair of the ACL-rupture was done. The most concomitant injury was a torn medial meniscus in 76.3%, a damaged lateral meniscus was found in 17.1%, chondromalacia was seen in 53%, either of tibia, femur or patella. Nearly 60% of the patients could resume their former sports activities in some cases on a lower level, whereas 33% had to change their sport or even had to give up any sport. 75%-80% of the patients with partial or total meniscectomy and 90% of those without meniscectomy estimated the outcome as good or fair. In contrast to this 61% rsp. 86% of the patients with partial or total meniscectomy had an osteoarthritis of grade III and IV, patients without meniscectomy in only 23%.

On the basis of clinical cases, the application possibilities of a newly developed portable EMG amplifier in the field of physiotherapy. The device permits continuous recording of the EMG activity of the muscles requiring therapy over any desired period of time.

Emergency caesarean section was performed in a 40-year-old woman with solutio placentae. A Couvelaire uterus was diagnosed, showing typical blue-purple discolorations of the uterine wall, which are in fact haemorrhages caused by disseminated intravascular coagulation.

The equipment available for rehabilitation of patients with joint conditions still lacks a device that, in common with usual physiotherapeutic measures (manipulation, proprioceptive neuromuscular facilitation, Bobath therapy), is based on traction and/or compression or oscillating forms. The novel "Shoulder Rotator" is such a simple device for the variable treatment of shoulder disorders in all three spatial dimensions. After individual instruction, the patient performs rotating glenohumeral exercises with simultaneous glenohumeral joint traction, compression, or oscillations against static or dynamic resistance. The "Shoulder Rotator" is similar to the established continuous passive motion device for the shoulder and is mounted on a mobile chair. The electronic device control is computerised and permits a wide variety of treatment options, individual regimes, and documentation. The oscillating, compression/distraction mode of operation provides an analgesic effect. The isolated compression mode along the rotatory axis enables conditioning of joint proprioception. The distraction mode along the rotatory axis facilitates muscular relaxation. Resistive rotatory exercises strengthen the rotatory glenohumeral muscles and help centre the Numeral head in the glenoid. In addition to the advantage of adding documentation of treatment progress as required for evidence-based medicine, this novel device may bring about a cost-effective, genuine quality improvement in shoulder rehabilitation.

The equipment available for rehabilitation of patients with joint conditions still lacks a device that, in common with usual physiotherapeutic measures (manipulation, proprioceptive neuromuscular facilitation, Bobath therapy), is based on traction and/or compression or oscillating forms. The novel "Shoulder Rotator" is such a simple device for the variable treatment of shoulder disorders in all three spatial dimensions. After individual instruction, the patient performs rotating glenohumeral exercises with simultaneous glenohumeral joint traction, compression, or oscillations against static or dynamic resistance. The "Shoulder Rotator" is similar to the established continuous passive motion device for the shoulder and is mounted on a mobile chair. The electronic device control is computerised and permits a wide variety of treatment options, individual regimes, and documentation. The oscillating, compression/distraction mode of operation provides an analgesic effect. The isolated compression mode along the rotatory axis enables conditioning of joint proprioception. The distraction mode along the rotatory axis facilitates muscular relaxation. Resistive rotatory exercises strengthen the rotatory glenohumeral muscles and help centre the humeral head in the glenoid. In addition to the advantage of adding documentation of treatment progress as required for evidence-based medicine, this novel device may bring about a cost-effective, genuine quality improvement in shoulder rehabilitation.

In our laboratory for biomechanics, a new isolation amplifier was developed with which to record the electromyographic activity of muscles inaccessible to surface electrodes, in particular that of the rotator cuff. Our basic premisses were maximum safety for the patient or subject investigated, and optimal signal processing. These were achieved by a triple galvanic separation of the patient/subject from the battery power supply and the signal cables and by careful selection of the electronic components.

The purpose of this study was to evaluate the efficacy of three screening tests in detecting glaucoma in its early stage: the Tendency Oriented Perimetry (TOP) and Frequency Doubling Perimetry (FDP) visual field tests, and the Glaucoma Diagnostic (GDx) nerve fibre layer analyser. Eighteen patients with glaucoma who showed an early defect on HFA c 24-2 and twenty normals underwent the three tests. TOP showed a sensitivity of 94.4% and a specificity of 75%, FDP showed a sensitivity of 72.2% and a specificity of 100%, and GDx a sensitivity of 77.7% and a specificity of 60%.

Isolated fractures of the Trochlea humeri are only rarely seen because in case of indirect trauma this portion of the elbow is only partially exposed to transmitted forces and in case of direct injury adjacent elements are also involved. On the lateral films a half-moon shaped fragment in front of the Humerus together with joint effusion are indicative of this type of fracture. Depending on the grade of dislocation of the fragment, which has to be shown radiologically, conservative or operative management are chosen.

103 patients with 106 Müller straight stem prostheses could be evaluated clinically and radiologically after an average follow-up period of 6.8 years (range 5 to 10 ys.). Although until now no revision for aseptic loosening has become necessary 3 p.c. of the stems and 11 p.c. of the acetabular components showed radiological loosening. The clinical results were rated as satisfactory. After surgery 67 p.c. of the patients were completely painfree, 28 p.c. still had slight pain, 4 p.c. moderate and 1 p.c. severe pain. The investigation concentrated particularly on radiographic changes of the interface of the femur. Whereas radiolucency typically was non-progressive and located in the proximal part of the femur we found an increasing atrophy of the cortical bone on the calcar. Moreover, we found a continuous and increasing subsidence of the stem during the whole period of observation. At the time of follow up 56 p.c. of the straight stems had subsided about 2 mm and more. Calcar atrophy and radiolucency were significantly less present in femurs with a tapered medullary canal than in those with a cylindrical shape.

In our laboratory for biomechanics, a new isolation amplifier was developed with which to record the electromyographic activity of muscles inaccessible to surface electrodes, in particular that of the rotator cuff. Our basic premisses were maximum safety for the patient or subject investigated, and optimal signal processing. These were achieved by a triple galvanic separation of the patient/subject from the battery power supply and the signal cables and by careful selection of the electronic components.

This paper presents the results of histologic studies conducted in the context of tenosynovectomy of the flexor tendons to treat carpal tunnel syndrome. The most common findings were inflammatory changes of the synovial sheath, vascular pathology and fibrous changes of the connective tissue.

Following irrigation-suction drainage and synovectomy in 68 knee joints for empyema between 1971 and 1987, all were available for clinical and radiological follow-up. Since in 24 cases the empyema occurred after total knee arthroplasty, this group of patients was evaluated separately. The mean follow-up time in the no-prosthesis group was 8.3 and that in the prosthesis group, 5.3 years. In particular the aetiological factors, the bacterial pathogens and the effect of infection on radiological signs of degeneration were studied. The clinical results, including subjective findings, were assessed with the aid of HSS score. Our late results show that the prognosis for knee joint empyema can be rated as good if it is diagnosed early and treated aggressively. The poor outcome in a few cases was rather the result of underlying local disease and concomitant factors, and seemed not to be an immediate consequence of the infection itself. The relatively poor results in prosthesis group have to be referred predominantly to cases dating from the early years of total arthroplasty, with implants of the metal-on-metal type.

In this paper the kinematics of arm abduction in the scapular plane of 38 healthy experimental subjects is reported. The ratio of the glenohumoral and the scapulothoracic components of the motion were determined and the influence of the abduction speed and of the external load on it were investigated. The investigation of the effect of abduction speed involved all 38 subjects. Each of them performed one slow and one fast abduction. Statistical analysis showed that there were large differences between individuals, but that for any one individual the abduction process is essentially reproducible. For the one individual there is a strong, linear relationship between glenohumeral and scapulothoracic rotation. The slope of the regression of the glenohumeral component on total arm abduction varied from 0.75 to 0.5 with a sample mean of 0.66. It means that only two-thirds of arm abduction occurs in the glenohumeral joint, the remaining third taking place via scapular rotation. In slowly performed abductions the slope of the regression was significantly greater than in the high-speed movements, but differences were very small. In the investigation of the effect of external load, statistical analysis indicated that the slope of the intraindividual regression is largely independent of the load. The possibility of observer bias was analysed, too. It was found that the standard deviation of the abduction parameters determined by different observers was between 6 and 10% of that between different experimental subjects. RELEVANCE: A knowledge of the kinematics of the shoulder joint is necessary to understand subacromial pathology and in particular impingement problems. The scapulohumeral rhythm depends on the balanced and coordinated function of the muscles involved. The activation pattern of the abductor muscles, as reflected in shoulder kinematics, seems to be individual and stored as an engram.

Thirty-one elbow joints in 29 patients (28 males, only 1 female), operated on for osteochondritis dissecans, were available for follow-up after an average of 10 years. The mean age at diagnosis was 24.4 years, but 11 patients were younger than 20. In 23 out of 29 patients the right elbow was involved, including 2 cases with bilateral involvement. In 20 cases removing the free bodies was the only surgical procedure performed, but in 2 cases it was combined with resection of the radial head. At follow-up, only one-third of the patients had no complaints. Nevertheless, daily activity was not restricted for any of the cases. Degenerative arthritic changes were found in only a few cases. These results are illustrated by means of three typical cases, which are compared with six similar cases in the international literature.

We have carried out an electromyographical examination of the activity of five different regions of the deltoid muscle during abduction/adduction in various body postures with different biomechanical actions of arm gravity. The results show that the deltoid action is highly differentiated in its different regions and is not restricted only to the generation of an abducting moment in the shoulder joint. There is obviously a biomechanical contribution, mainly by its spinal and clavicular regions, to the stabilization of the glenohumeral joint and to the control of the selected plane of abduction.

In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after Goldthwait-operation. The subjective and clinical findings were excellent rsp. good in 70%, whereas the x-ray findings showed osteoarthritis of the femoropatellar joint in 60%. Concerning the aetiopathological factors we found an increased external torsion of the afflicted extremity measured by computed tomography.

A case of septic Candida albicans arthritis of the knee in a patient with systemic candidiasis is presented. Systemic and intra-articular cellular immune responses to C albicans and various bacterial antigens were monitored for 15 weeks. It is shown that the candida induced blastogenesis of synovial fluid lymphocytes was much more stimulated than that of peripheral blood lymphocytes, and that the proportion of activated cells expressing HLA class II antigens was markedly increased in the synovial fluid. Strong cellular immune responses to Candida albicans could still be shown many weeks after the synovial fluid aspirates had become sterile. For the first time synovial fluid derived, CD4 positive T lymphocyte clones with specificity for candida antigens were characterised and further propagated in vitro.

The radiation exposure during biomechanical investigation of the shoulder joint done with a digital radiography system (Polytron 1000 VR - Siemens) was measured experimentally. Total radiation dose and surface dose were determined by phantom measurements. The radiation exposure per image is about 1/6 to 1/7 of that of a conventional study. The digital radiography system used is thus suitable for kinesiologic studies of large joints in healthy volunteers.

Calcifying tendinitis of the shoulder joint is a relatively common condition. Its pathogenesis is well documented in anatomical-pathological terms. The clinical observation of four unusual locations in the upper limb makes us to suspect the same pathological process as in the supraspinatus location. The clinical course of calcifying tendinitis in a typical location is discussed in detail.

Cartilage damage in the knee joints of rats was induced with a single intraarticular injection of 10 mg papain. Such damage was indicated by a decrease in the content of glycosaminoglycans and histologically detectable alterations in the surface of patellar cartilage. Daily treatment of the rats with N-acetylglucosamine by gavage led to an increase of the glycosaminoglycans of the cartilage and of incorporation of the radioactive precursor of glycosaminoglycan synthesis, 3H-glucosamine hydrochloride, in comparison to control animals treated with saline. The incidence of pathological alterations of the cartilage in histological samples was reduced.

Basing on 13 dislocations of 215 total hip arthroplasties are presented the characteristics of this complication. All things considered the dislocation following total hip arthroplasty seems to be no serious complication, if there is no severe operation failure and if the necessary treatment consisting in plastic cast immobilisation is performed.

A series of 90 patients, 85 males and 5 females, all with ACL-ruptures had a follow up between 5 and 12 years. All of them had a primary arthrotomy with or without meniscectomy but in no case an operative repair of the ACL-rupture was done. The most concomitant injury was a torn medial meniscus in 76.3%, a damaged lateral meniscus was found in 17.1%, chondromalacia was seen in 53%, either of tibia, femur or patella. Nearly 60% of the patients could resume their former sports activities in some cases on a lower level, whereas 33% had to change their sport or even had to give up any sport. 75%-80% of the patients with partial or total meniscectomy and 90% of those without meniscectomy estimated the outcome as good or fair. In contrast to this 61% rsp. 86% of the patients with partial or total meniscectomy had an osteoarthritis of grade III and IV, patients without meniscectomy in only 23%.

Four cases of malignant synovialoma (synonym: synovial sarcoma) of the sole of the foot are reported. A striking feature of all four cases was the long delay before the final diagnosis was made. Although this condition is rare, our cases nevertheless show that chronic neuralgiform pain close to the joint should prompt consideration of this tumor in the differential diagnosis. However, even surgical revision or explorations do not always reveal the tumor.

On the basis of clinical cases, the application possibilities of a newly developed portable EMG amplifier in the field of physiotherapy. The device permits continuous recording of the EMG activity of the muscles requiring therapy over any desired period of time.

Melorheostosis, Osteopoikilosis and Osteopathia striata Clinical Relevance and Bone Scintigraphy Melorheostosis, Osteopoikilosis and Osteopathia striata are rare conditions. Although there is no casual therapy for any of the three diseases, differential diagnosis is important because concomitant or resulting impairments deserve orthopaedic or medical treatment. The analysis of typical cases with their clinical, roentgenological and radionuclide presentation shows the need of an accurate diagnosis to prevent senseless treatment or lost therapeutic opportunities.

Osteochondritis dissecans (OD) of the lateral tibial condyle is a rare condition. A review of the literature revealed only nine cases in seven patients. We report about a new case. It is widely accepted that this form of OD originates from an accessory center of ossification. Our case supports this theory. Although comparative roentgenograms of the left knee, taken because of complaints in the right one, were interpreted to be normal, retrospective analysis clearly revealed the lateral intercondylar eminence of the left knee to have been irregular many years before the onset of symptoms. Association with a classical OD in the contralateral knee is striking in most of the reported cases.

Infekte stellen immer noch die am meisten gefurchtete Komplikation bei der Endoprothetik dar. Wegen ihrer fast subkutanen Lage sind Knieendoprothesen hier besonders anfallig [1, 3, 5, 7].

We present a case of radial tunnel syndrome with long-standing complete paralysis, successfully treated by internal neurolysis and reconstruction of the perineurium. The therapeutic attitude is discussed and the differential diagnosis with resistant tennis elbow is stressed.

Surgical hernia repair in an apparently normal man leaded to the diagnosis of internal male pseudohermaphroditism after removal of a cystic structure which proved to be a remnant of the Müllerian duct on microscopic examination. The diagnosis was confirmed at explorative laparotomy in search of the second testicle. The terminology of the condition is reviewed and the therapeutic attitude is discussed.