[Tumor-induced osteomalacia caused by an FGF23-secreting myopericytoma : Case report and literature review]. / Tumorinduzierte Osteomalazie, verursacht durch ein FGF23-sezernierendes Myoperizytom : Literaturübersicht und Fallbericht.

BACKGROUND: The symptoms of muscle weakness, bone pain and fragility fractures can be an indication of osteomalacia. Phosphate is often not considered within osteologic parameters, decreased levels are therefore easily overseen. The additional test for fibroblast growth factor 23 (FGF23) as indicator for tumor-induced osteomalacia (TIO) is still largely unfamiliar. OBJECTIVE: By emphasizing the role of phosphate and furthermore FGF23 in bone metabolism illustrated by the long-term disease process of our clinical case we would like to introduce these parameters to a broader public. METHODS: We performed a literature search via PubMed and Google Scholar with the relevant key words and summarized the diagnostic and therapeutic information. The studies evaluated were mainly case reports. We present a case report of a 70-year-old patient with TIO and a myopericytoma and retrospectively analyzed the clinical case. The follow-up was 6 months. RESULTS: Our literature search found one case of TIO and evidence of FGF23 among 124 cases of myopericytomas in total. Over 300 cases of TIO are reported. In our case, we retrospectively found an FGF23-secreting myopericytoma in the phosphaturic mesenchymal tumors (PMT) group to be the cause of pseudarthrosis on the right humerus shaft and increasing disablement in a patient with osteomalacia. After surgical resection the patient was mobile again, and the osteologic parameters, especially phosphate, normalized from 0.21 to 1.52 mmol/l. CONCLUSION: Low phosphate levels are the decisive indication of TIO in our case. Therefore, we should always think of phosphate level control when dealing with osteomalacia. A hypophosphatemia and hyperphosphaturia should be recognized in time and be diagnostically verified. The additional FGF23 test (c-terminal and intact FGF23) should be considered.

[Closed medial talus dislocation with damage to the tibial nerve]. / Geschlossene mediale Talusluxation mit N.-tibialis-Schädigung.

This article reports a case of medial dislocation of the talus as a rare injury caused by a fall from a low height.Treatment recommendations given in the literature for this rare injury are heterogeneous but closed reduction is predominant. Little is known about possible obstacles in closed reduction. The known complications include posttraumatic arthritis and necrosis of the talus.A posttraumatic lesion of the tibial nerve has not been reported, which is why a treatment recommendation is illustrated and discussed based on this case report.

Mid-term outcome of arthroscopic AMIC for the treatment of articular cartilage defects in the knee joint is equivalent to mini-open procedures.

INTRODUCTION: We present the first retrospective study that compares two various autologous matrix-induced chondrogenesis (AMIC) surgical interventions to repair grade III-IV cartilage defects in the knee. Patients who underwent minimally invasive (arthroscopy) or open (mini-arthrotomy) AMIC were followed up to 2 years to investigate if minimally invasive AMIC is superior to open procedures. MATERIALS AND METHODS: Overall n = 50 patients with focal and contained grade III-IV articular cartilage defects in the knee joint were followed in a consecutive cohort study. 20 patients were treated arthroscopically (female 7, male 13; age: mean 38.2 years, range 18-70 years; BMI: mean 27.0, range 18.7-34.7; defect size: mean 3.1 cm2, range 1.0-6.0 cm2), and 30 patients via mini-arthrotomy (female 13, male 17; age: mean 34.4 years, range 14-53 years, BMI: mean 23.9, range 18.4-28.7; defect size: mean 3.4 cm2, range 1.5-12.0 cm2). The primary defect localization was the medial femoral condyle. RESULTS: AMIC led to a significant improvement of VAS pain, KOOS and Lysholm scoring for up to 2 years compared to pre-op. Outcome analysis revealed no significant differences between the two different surgical approaches. CONCLUSIONS: Our results suggest that mini-open AMIC is equivalent to the arthroscopic procedure. The anticipatory hypothesis that minimally invasive approaches bring greater patient benefit per se could not be confirmed. Therefore, we recommend to perform AMIC where indicated and suggest that the surgeon's personal skills profile guide the choice of surgical approach. LEVEL OF EVIDENCE: III.

Modified direct anterior approach in minimally invasive hip hemiarthroplasty in a geriatric population: a feasibility study and description of the technique.

INTRODUCTION: The direct anterior approach (DAA) is generally accepted method for minimal invasive arthroplasty of the hip. As good results for total hip arthroplasty are already published, there is a lack of evidence for the implantation of bipolar hip hemiarthroplasty (BHH) in elderly patients with osteoporosis after femoral neck fracture. MATERIALS AND METHODS: For hip arthroplasty using a direct anterior approach (DAA) in elderly patients with femoral neck fractures, a number of modifications of the original technique are being described. The modified DAA considers in particular the co-morbidity and the bone quality of the geriatric patient population. A consecutive series of 16 hemiarthroplasties using this technique is presented. In all 16 cases, the BHH was implanted in modified DAA technique. Mobility measured by 4-item Barthel Index, pain via visual analogue scale (VAS), duration of surgery, external length of incision and blood loss were evaluated. RESULTS: There was no major operative complication during the procedures. The pain level decreased from 7 (preoperatively) to 0 at postoperative day 40. The Barthel Index increased from 5 at first postoperative day to 40 at day 40. Early postoperative mobilisation is efficiently accelerated. Mean operating time was 71 min; the medium skin incision length was 8 cm. The mean haemoglobin level decreased from 118 g/dl preoperatively to 101 g/dl at first postoperative day. CONCLUSION: The described modifications of the DAA help to implant a BHH gently in elderly patients with increasing risk of complications like iatrogenic fractures, wound or prosthesis infections and haematoma. This will hopefully lead to a faster rehabilitation and lower mortality rate for patients with femoral neck fractures in the future.

Correlation of the Histological ICRS II Score and the 3D MOCART Score for the Analysis of Aged Osteochondral Regenerates in a Large Animal Model.

OBJECTIVE: Reliable outcome measures are essential to predict the success of cartilage repair techniques. Histology is probably the gold standard, but magnetic resonance imaging (MRI) has the potential to decrease the need for invasive histological biopsies. The 3D magnetic resonance observation of cartilage repair tissue (MOCART) score is a reliable yet elaborate tool. Moreover, literature is controversial concerning the correlation of histology and MRI. DESIGN: To test the applicability of the International Cartilage Regeneration and Joint Preservation Society (ICRS) II and MOCART 3D score for the evaluation of aged osteochondral regenerates in a large animal model, and to identify correlating histological and MRI parameters. Osteochondral defects in medial femoral condyles of n = 12 adult sheep were reconstructed with biodegradable bilayer implants. About 19.5 months postoperation, n = 10 joints were analyzed with MRI (3D MOCART score). Histological samples were analyzed using the ICRS II score; both pre- and post-training. The intraclass correlation coefficient, the inter-rater reliability, and the 95% confidence interval were calculated. Matching histological and MRI parameters were tested for correlation. RESULTS: We found a statistically significant correlation of all histological parameters. MRI parameters reflecting "overall" assessments had very strong inter-rater correlations. Statistically significant strong correlations were found for the MRI parameters defect filling, cartilage interface, bone interface, and surface. For defect overall (MRI) and overall assessment (ICRS II), we found a significant yet mild correlation. CONCLUSIONS: The ICRS II and the 3D MOCART score are applicable to aged osteochondral regenerates. Prior training on the scoring systems is essential. Select MRI and histological parameters correlate; however, the only statistically significant correlation was found for overall assessment.

Biopolymer augmentation of the lag screw in the treatment of femoral neck fractures--a biomechanical in-vitro study.

The cut-out of the sliding screw is one of the most common complications in the treatment of intertrochanteric fractures. The reasons for the cut-out are: a suboptimal position of the hip-screw in the femoral head, the type of fracture and poor bone quality. The aim of this study was to reproduce the cut-out event biomechanically and to evaluate the possible prevention of this event by the use of a biopolymer augmentation of the hip screw. Concerning the density and compression force of osteoporotic femoral bone polyurethane foam according to the terms of the Association for Standard Testing Material (ASTMF 1839-97) was used as test material. The polyurethane foam Lumoltan 200 with a compression force of 3.3 Mpa and a density of 0.192 g/cm(3) was used to reproduce the osteoporotic bone of the femoral fragment (density 12 lbm/ft(3)). A cylinder of 50 mm of length and 50 mm of width was produced by a rotary splint raising procedure with planar contact. The axial load of the system was performed by a hydraulic force cylinder of a universal test machine type Zwick 1455, Ulm, Germany. The CCD-angle of the used TGN-System was preset at 130 degrees. The migration pattern of the hip screw in the polyurethane foam was measured and expressed as a curve of the distance in millimeter (mm) against the applied load in Newton (N) up to the cut-out point. During the tests the implants reached a critical changing point from stable to unstable with an increased load progression of steps of 50 Newton. This unstable point was characterized by an increased migration speed in millimeters and higher descending gradient in the migration curve. This peak of the migration curve served as an indicator for the change of the hip screw position in the simulated bone material. The applied load in the non-augmented implant showed that in this group for a density degree of 12 (0,192 g/cm(3)) the mean force at the failure point was 1431 Newton (+/- 52 Newton). In the augmented implant we found that the mean force at the failure point was 1987 Newton (+/- 84 Newton). This difference was statistically significant. In conclusion, the bone density is a significant factor for the stability of the hip screw implant. The osteosynthesis with screws in material with low density increases the chance for cut-out. A biopolymer augmented hip screw could significantly improve the stability of the fixation. The use of augmentation with a fast hardening bone replacement material containing polymer-ceramic changes the point of failure under axial load in the osteoporotic bone model and could significantly improve the failure point. Our study results indicate, that a decrease of failure in terms of cut-out can be achieved with polymer augmentation of hip screws in osteoporotic bones.

Clinical results of resection arthrodesis by triangular external fixation for posttraumatic arthrosis of the ankle joint in 89 cases.

UNLABELLED: The methods for ankle arthrodesis differ significantly, probably a sign that no method is clearly superior to others. In the last ten years there is a clear favour toward internal fixation. We retrospectively evaluate the technique and evaluate the clinical long term results of external fixation in a triangular frame. PATIENTS AND METHODS: From 1994 to 2001 a consecutive series of 95 patients with end stage arthritis of the ankle joint were treated. Retrospectively the case notes were evaluated regarding trauma history, medical complaints, further injuries and illnesses, walking and pain status and occupational issues and the clinical examination before arthrodesis. Mean age at the index procedure was 45.4 years (18-82), 67 patients were male (70.5%). Via a bilateral approach the malleoli and the joint surfaces were resected. An AO fixator was applied with two Steinmann-nails inserted with approximately 8 cm distance in the distal tibia, one in the neck of the talus and one in the dorsal calcaneus. The fixator was removed after approximately 12 weeks. Follow up examination at mean 4.4 years included a standardised questionnaire and a clinical examination including the criteria of the AOFAS-Score and radiographs. RESULTS: Due to different complications, 8 (8.9%) further surgical procedures were necessary including 1 below knee amputation. In 4 patients a non-union of the ankle arthrodesis developed (4.5%). The mean AOFAS score improved from 20.8 to 69.3 points. CONCLUSION: Non-union rates and clinical results of arthrodesis by triangular external fixation of the ankle joint do not differ to internal fixation methods. The complication rate and the reduced patient comfort reserve this method mainly for infected arthritis and complicated soft tissue situations.

Subjective evaluation of a novel method of dose reduction by optical re-exposure of conventional radiographs - a multi-observer region of interest evaluation in an animal model.

A procedure previously been described that has an effect on the image quality and radiation dose of conventional radiographs already at the time of acquisition [Paech A, Schulz AP, Hahlbrauck B, Kiene J, Wenzl ME, Jürgens C. Physical evaluation of a new technique for X-ray dose reduction: measurement of signal-to-noise ratio and modulation transfer function in an animal model. Physica Medica 23 (2007):33-40]. This development is using X-ray sensitization by optical re-exposure. Aim of this study was to establish if the results of optical re-exposure measured with SNR and MTF also meant that the subjective quality of 50% dose-reduced and re-exposed radiographs of bony structures was equal or better than conventional full dose radiographs of the same area. Freshly slaughtered anterior shoulders of lambs served as the animal model. A comminuted fracture in the middle of the shaft was artificially produced. After taking a normal exposed reference image, dose-reduced, five underexposed images were prepared. These underexposed X-rays were then optically re-exposed for a defined period of time before development. The subjective changes in the image quality (information loss or gain) of the images were compared to the reference image and evaluated by 16 physicians with large experience in diagnosis of orthopedic radiographs. The evaluation of the observers scoring showed a significant decrease in the subjective image quality regarding the detail recognition in all images apart from the images re-exposed for 60s. In conclusion, there is a possibility of reducing the collective radiation dose whilst keeping a high degree of diagnostic reliability. Film sensitization provides a technically simple and inexpensive procedure, which can be easily integrated into common film development processes and could considerably reduce patient radiation exposure as well as improve image quality and thus detail recognition.

Physical evaluation of a new technique for X-ray dose reduction: measurement of signal-to-noise ratio and modulation transfer function in an animal model.

Aim of this study was to record objective changes in image quality of optically re-exposed, radiation-reduced X-ray images in comparison to a normally exposed reference image in an animal model. Under investigation is the question if optical re-exposure of conventional, radiation-reduced X-ray images partially or even fully compensates the loss of information caused by underexposure. Dose-reduced, underexposed images were prepared by reducing the mAs product to 50% with constant anode voltage. Reproduction of the image was performed with a 52% decrease in the radiation dose. Comparing different re-exposure times, the optimal time was found to be 60s. These underexposed X-rays were then optically re-exposed for a defined period of time before development. In all X-ray images of the animal model, different osseous structures were defined as regions of interest (ROI) for evaluation of the objective changes in image quality. The density curves were plotted with the two-beamed densitometer. The contrast transfer factors as the function of local frequency were determined from this, which served as the basis for calculating the modulation transfer factor. To establish if X-ray sensitisation by optical re-exposure leads to a change in the sensitometric gradation, the sensitometric curves were determined using a standardized aluminum scale and thermal luminescence dosimetry. In the comparison the lowest correlation with the standard technique film (X-ray 1) was seen in the purely dose-reduced X-ray. In the range of 1.6-3.4Lp/mm, both SNR curves have an identical course. Despite a 52% dose reduction in the re-exposed image, both densitometry curves of the conventional and re-exposed X-ray show an almost identical distribution of the transmittance levels. In conclusion film sensitisation provides a technically simple and inexpensive procedure, which is easily integrated into previous film development processes and considerably reduces the patient radiation exposure as well as clearly improving the image quality.

[Clinical impact of operative multidisciplinarity for severe defect injuries of the lower extremity]. / Klinische Bedeutung der operativen Interdisziplinarität bei schweren Defektverletzungen der unteren Extremität.

BACKGROUND: The aim of this study was to examine the impact of our multidisciplinary therapeutical concept (MTC) on the clinical outcome in posttraumatic defect injuries of the lower extremity. PATIENTS AND METHODS: Since 1999, we have performed a free tissue transfer in 37 patients. In group 1 (n = 21), our MTC was started more than two weeks (range: 17 to 83 days) after trauma and in group 2 (n = 16) within two weeks (range: four to twelve days) after trauma. Both groups were comparable with respect to trauma severity. RESULTS: 100 % patients of group 1 and 25 % patients of group 2 had clinical and microbiological manifestations of wound infection after admission in our clinic. Significantly more operations were necessary in group 1 compared to group 2 (7.3 +/- 2.6 versus 2.9 +/- 0.8; p < 0.05), until definitive wound closure could be achieved. The postoperative course was uneventful in 35 cases. All injured extremities could be salvaged. Multistaged bone reconstructions by means of spongious or tricortical bone from the iliac crest were successful in all cases. Hospital stay after admission to our clinic was significantly longer in group 1 compared to group 2 (57 +/- 12 days versus 31 +/- 7 days, p < 0.05). CONCLUSIONS: In our study, the early start of MTC significantly reduced the risk for wound infection, the number of surgical revisions before definite wound closure and time until bone and wound healing was completed.

Arthroscopic-assisted treatment of a reversed hill-sachs lesion: description of a new technique using cerament.

Purpose. Impaction fractures of the anterior aspect of the humeral head, the reversed Hill-Sachs lesion, are common in posterior shoulder dislocation. We present a new technique to address these lesions arthroscopic-assisted with the use of a bone substitute. Methods. We report the case of a 45-year-old male with a reversed Hill-Sachs lesion after posterior shoulder dislocation. Initially a glenohumeral arthroscopy is performed to address concomitant intra-articular injuries. Guided by the k-wire a cannulated sizer was inserted for reduction of the fracture under arthroscopic visualization. For reduction of the impacted part of the humeral head the subcortical defect was filled with an injectable bone substitute (Cerament) to prevent secondary dislocation. Results. X-ray at follow-up 6 months after the index procedure documents the bony remodeling of the bone substitute. At that time the patient was pain-free (VAS 0) and satisfied with the outcome (Constant score: 78, Rand-36 score: 84, Rowe score: 81) with a good ROM. Conclusions. In conclusion, arthroscopic-assisted reconstruction of reversed Hill-Sachs lesions with an injectable bone substitute is feasible and may provide patients with all the benefits of an anatomic reconstruction with decreased risks related to open surgery.

Midterm Results of 58 Fractures of the Coronoid Process of the Ulna and their Concomitant Injuries.

BACKGROUND: In general, fractures of the coronoid process are rare and usually occur in combination with additional elbow joint injuries. The treatment of these injuries aims to regain a stable as well as a flexible and loadable joint. Although there is currently little evidence, therapy recommendations remain controversial. Therefore, the aim of this study was to prognostically determine relevant factors for therapy recommendation by analysing a representative patient population of two trans-regional trauma centres. MATERIAL AND METHODS: Seventy-seven patients with a fracture of the coronoid process were treated within an 8-year period (2001 to 2009). After an average of 48 months (SD 31), treatment outcome of 58 patients (75%) was acquired. The results were statistically analysed. RESULTS: The average age of the patient was 51.8 years (SD 13.6); 36 were male and 34 had a fracture on the right arm. Applying the fracture types of the coronoid process in accordance with Regan/Morrey, the result was: Type I (19), II (17) and III (22). Further injuries were also detected: 40 radial head fractures, 17 proximal ulnar fractures and 2 fractures of the olecranon. A luxation was detected in 44 of the 58 patients (76%). The patients' average MEPS (Mayo Elbow Performance Score) was 80.6 points (SD 18), with significant differences between the various therapy strategies. Fifteen% of the coronoid process fractures were reconstructable to a limited extent only by means of osteosynthesis. In 33% of the patients, instabilities remained. The average extension/flexion came to 107° (SD 28), and pronation and supination 153° (SD 38). CONCLUSION: At present, a surgical therapy of ligamentary injuries cannot be statistically justified. A stable osseous reconstruction appears to make more sense. The strongest negative prognostic parameters in our patient population were: therapy with an external fixator, immobilisation for more than 21 days, the occurrence of complications and unstable osteosyntheses on the coronoid process.

Initial results of the s3-humerus plate.

Fractures of the humeral head account for 5% of all fractures and incidence increases with age. Depending on fracture form and patients age a wide variety of therapeutical options exist. Stable fractures can be treated conservatively, while the majority of unstable and displaced fractures require surgical treatment. Many different surgical options are available; open reduction and internal fixation are widely preferred. The S3 Proximal Humerus Plate is a contoured plate to match the complex shape of the proximal humerus. It is designed to be positioned distal to the greater tuberosity preventing subacromial impingement.Between august 1 and 30, 2007, 5 patients meeting the inclusion criteria (that is primary operative stabilization within 7 days after trauma in a standardized way and minimal follow up period of 3 month) with acute fractures of the proximal humerus were treated with S3 Proximal Humerus Plate. Follow up was performed using the Constant Score. The mean age was 59.0 years. According to the Neer classification fractures were rated as Neer 2,3 and 4. A mean Constant score of 72.3 (57-86) points was obtained.We did not observe any complications like humeral head necroses, loss of reduction, deep infection or breakage of the plate.