Peter Jürgen Meeder

Treatment of Painful Vertebral Fractures by Kyphoplasty in Patients With Primary Osteoporosis: A Prospective Nonrandomized Controlled Study

This study investigates the effects of kyphoplasty on pain and mobility in patients with osteoporosis and painful vertebral fractures compared with conventional medical management.

Strontium enhances osseointegration of calcium phosphate cement: a histomorphometric pilot study in ovariectomized rats

BackgroundCalcium phosphate cements are used frequently in orthopedic and dental surgeries. Strontium-containing drugs serve as systemic osteoblast-activating medication in various clinical settings promoting mechanical stability of the osteoporotic bone.MethodsStrontium-containing calcium phosphate cement (SPC) and calcium phosphate cement (CPC) were compared regarding their local and systemic effects on bone tissue in a standard animal model for osteoporotic bone. A bone defect was created in the distal femoral metaphysis of 60 ovariectomized Sprague-Dawley rats. CPC and SPC were used to fill the defects in 30 rats in each group. Local effects were assessed by histomorphometry at the implant site. Systemic effects were assessed by bone mineral density (BMD) measurements at the contralateral femur and the spine.ResultsFaster osseointegration and more new bone formation were found for SPC as compared to CPC implant sites. SPC implants exhibited more cracks than CPC implants, allowing more bone formation within the implant. Contralateral femur BMD and spine BMD did not differ significantly between the groups.ConclusionsThe addition of strontium to calcium phosphate stimulates bone formation in and around the implant. Systemic release of strontium from the SPC implants did not lead to sufficiently high serum strontium levels to induce significant systemic effects on bone mass in this rat model.

Bone cement implantation syndrome

Bone cement implantation syndrome (BCIS) is characterised by hypotension, hypoxaemia, cardiac arrhythmias, cardiac arrest or any combination of these, leading to death in 0.6–1% of patients. One of the mechanisms suggested to explain these complications is diffuse microembolisation of the lungs as a consequence of extrusion of the bone marrow content by the pressurised bone cement. By reducing intramedullary pressure and changing the operative technique, BCIS can be diminished, but deaths still occur. An anaphylactoid mechanism as a major factor in BCIS is receiving renewed attention since increased plasma histamine levels were recently demonstrated after the implantation of bone cement and a prosthesis. Therefore, we conducted a prospective, randomised study to demonstrate the potential benefit of histamine-receptor-blocking agents in patients undergoing cemented hip arthroplasty. Thirty patients were divided into two groups: group 1, the control group, received no histamine-receptor-blocking agents; group 2, the antihistamine group, received H1 and H2-receptor-blocking agents in standard dosages preoperatively. Both groups were comparable concerning age, sex and physical status (ASA criteria). There was no hospital mortality in either group. Thirteen patients of group 1 demonstrated a sudden fall by more than 10% of their blood pressure, level of PaO2 or both. Fourteen patients of group 2 showed similar changes. The mean decrease of blood pressure in group 1 was 14.6 mmHg (SD 36.8) and in group 2 20.5 mmHg (SD 33.43). The difference is not significant (P = 0.65). The mean decrease of PaO2 in group 1 was 30.5 mmHg (SD 30.5) and in group 2 33.4 mmHg (SD 34.1). The difference is not significant (P = 0.81). Overall, we found even a slight disadvantage for patients receiving antihistamine drugs (statistically not significant). Therefore, histamine-receptor-blocking agents do not have a prophylactic potential in BCIS.

External fixation of intra-articular fracture of the distal radius in young and old adults

Forty patients (18–89 years old, mean 58 years) with comminuted intra-articular fractures of the distal radial end (AO-type C 2 or C 3) treated with external fixation could be followed for an average of 2.3 years. After 3 weeks, the distraction was released, and after another 3 weeks, the device was removed. Complications seen were one malunion, one radial shaft fracture caused by excentric drilling of a Schanz screw, one Sudeck atrophy, and one subcutaneous pin-track infection. Radial and ulnar deviations were reduced to 52% and 71% of the untreated wrist, whereas the range of motion in the other planes reached about 80% or more of the healthy side. In all, 82.5% of the patients showed good or excellent radiological and functional results. This study demonstrates that external fixation of distal radial C 2 and 3 fractures for 6 weeks results in good recovery for young patients and elderly patients with osteoporosis.

Kyphoplasty for Patients With Multiple Myeloma Is a Safe Surgical Procedure: Results From a Large Patient Cohort

INTRODUCTION Only in recent years has balloon kyphoplasty gained significance in the treatment of vertebral fractures as an adequate minimally invasive vertebral stabilization technique. Kyphoplasty has also increasingly been used to treat vertebral osteolyses caused by multiple myeloma (MM). PATIENTS AND METHODS In our cohort of 76 patients with MM with a total of 190 vertebral fractures treated with kyphoplasty, we performed a 30-day postoperative analysis of cement leakage, neurologic symptoms, pulmonary embolism, and infections. RESULTS Painful osteolytic or fractured vertebrae or even imminent vertebral instability caused by osteolyses were seen as indications for kyphoplasty. One case of pulmonary embolism was observed because of cement leakage as the only postoperative complication. CONCLUSION By careful interdisciplinary indication setting and a standardized treatment model, kyphoplasty presents a very safe and effective procedure for the treatment of vertebral osteolyses and fractures caused by MM.

Minimal invasive Reposition und innere Stabilisierung osteoporotischer Wirbelkörperfrakturen (Ballonikyphoplastie)

Zusammenfassung.Operationsziel:Wiederaufrichtung eines frakturierten Wirbelkörpers mit einem aufblasbaren Ballonsystem, das minimal invasiv über Stichinzisionen transpedikulär platziert wird. Der geschaffene Hohlraum wird nach Entfernung der Ballons mit Polymethylmetacrylat-(PMMA-)Zement aufgefüllt und somit von innen her stabilisiert.Indikationen:Osteoporotische Kompressionsfrakturen von Wirbelkörpern mit erhaltener Lamina dorsalis (Hinterwand).Durch Metastasen bedingte Osteolysen im Wirbelkörper.Primäre gutartige Wirbelkörpertumoren, z. B. Hämangiome. Traumatische Wirbelkörperkompressionsfrakturen mit intakter Hinterwand.Kontraindikationen:Instabile Wirbelkörperfrakturen mit zerstörter Hinterwand.Gerinnungsstörungen.Bandscheibenleiden mit radikulärer Symptomatik.Vollständig zusammengebrochene Wirbelkörper (Vertebra plana).Operationstechnik:In Bauchlagerung unter Bildwandlerkontrolle beidseitiges transpedikuläres Vorschieben einer Hohlnadel bis in das dorsale Drittel des Wirbelkörpers. Entfernen der Yamshidi-Nadeln und Einbringen beider Arbeitskanülen über vorgelegte Führungsdrähte. Mit einem Handbohrer wird über die Arbeitskanülen in der Wirbelkörperspongiosa ein Kanal für die Ballonkatheter geschaffen. Einbringen der Ballonkatheter; langsames Auffüllen mit Kontrastmittel. Ständige Druckkontrolle über Manometer. Lagekontrolle durch Bildwandler in beiden Ebenen. Nach Aufrichtung des Wirbelkörpers wird der Ballon entleert und entfernt. Auffüllung des Hohlraums mit Knochenzement. Kontrolle im seitlichen Strahlengang, um einen Zementaustritt in den Spinalkanal zu vermeiden. Nach Aushärten des Zements Entfernen der Arbeitskanülen und Hautnaht.Ergebnisse:In einer prospektiven Studie an 95 Patienten mit osteoporotischen Wirbelkörperfrakturen (165 behandelte Wirbelkörper) zeigt sich nach Kyphoplastie und PMMA- oder Calciumphosphat-Zementauffüllung eine deutliche Beschwerdebesserung bei 89% der Operierten. Eine Wiederaufrichtung der Wirbelkörper war im Mittel um 16% der behandelten Wirbel möglich. Ein Zementaustritt—ohne Komplikationen—fand sich bei 14 Wirbelkörpern (8%) und lag somit deutlich unter den publizierten Werten bei der Vertebroplastie mit 20–70% Leckage.Abstract.Objective:Restoration of height of a fractured vertebral body with an inflatable balloon system introduced transpedicularly into the vertebral body. The system creates a cavity that is filled with bone cement. This minimally invasive procedure creates an internal stabilization.Indications:Osteoporotic vertebral compression fractures with an intact posterior wall.Osteolytic metastases.Primary benign vertebral tumors such as hemangiomata. Traumatic compression fractures with an intact posterior wall.Contraindications:Unstable burst fractures involving the posterior wall.Coagulopathies.Disk herniation accompanied by radiculopathy.Compression of entire vertebral body (vertebra plana).Surgical Technique:In prone position and under fluoroscopic control transpedicular placement of Yamshidi needles into the posterior third of the vertebral body through stab incisions. Insertion of guide wires through these needles for proper placement of working cannulae. Drilling of a channel for insertion of the balloon system. Under fluoroscopy in two planes, pressure-controlled filling of the balloon with a contrast medium. Once the proper vertebral height has been obtained, removal of contrast medium and balloon and filling of the cavity with cement avoiding any leakage into the spinal canal. Once the cement has hardened, removal of working cannulae, skin closure.Results:In a prospective study of 95 patients (165 vertebral bodies) with osteoporotic fractures treated with PMMA cement or calcium phosphate filling, we observed a marked symptom reduction in 89%. The average restoration of height amounted to 16%. Cement leakage not leading to any complications occurred in 14 vertebral bodies (8%), a percentage far below published values of 20–70%.

Minimally Invasive Reduction and Internal Stabilization of Osteoporotic Vertebral Body Fractures (Balloon Kyphoplasty)

AbstractObjective:Restoration of height of a fractured vertebral body with an inflatable balloon system introduced transpedicularly into the vertebral body. The system creates a cavity that is filled with bone cement. This minimally invasive procedure creates an internal stabilization.Indications:Osteoporotic vertebral compression fractures with an intact posterior wall. Osteolytic metastases. Primary benign vertebral tumors such as hemangiomata. Traumatic compression fractures with an intact posterior wall.Contraindications:Unstable burst fractures involving the posterior wall. Coagulopathies. Disk herniation accompanied by radiculopathy. Compression of entire vertebral body (vertebra plana).Surgical Technique:In prone position and under fluoroscopic control transpedicular placement of Yamshidi needles into the posterior third of the vertebral body through stab incisions. Insertion of guide wires through these needles for proper placement of working cannulae. Drilling of a channel for insertion of the balloon system. Under fluoroscopy in two planes, pressure- controlled filling of the balloon with a contrast medium. Once the proper vertebral height has been obtained, removal of contrast medium and balloon and filling of the cavity with cement avoiding any leakage into the spinal canal. Once the cement has hardened, removal of working cannulae, skin closure.Results:In a prospective study of 95 patients (165 vertebral bodies) with osteoporotic fractures treated with PMMA cement or calcium phosphate filling, we observed a marked symptom reduction in 89%. The average restoration of height amounted to 16%. Cement leakage not leading to any complications occurred in 14 vertebral bodies (8%), a percentage far below published values of 20–70%.

Students’ Attitude to Modern Teaching Principles in the Field of Traumatology

Introduction:This study evaluates the implementation of the reform study system HeiCuMed (Heidelberger Curriculum Medicinale) in the field of traumatology at the University of Heidelberg. Goals of the reform study system are in close relation to practical knowledge combined with improvement of social and communicative skills of the student.Materials and Methods:At the end of the course, questionnaires are distributed which evaluate three different topics: whether specific goals of the reform study system are achieved, which type of lesson was able to achieve these goals and what was the most effective way to acquire the necessary knowledge. Relevance of answers are evaluated with points (1, 2 no relevance; 4,5 high relevance; 3 neutral).Results:One hundred and forty-eight students undergo traumatological education within the new reform study system. Feedback of questionnaires is 59%. Specific goals like “Recognition of problems” and “interdisciplinary thinking” are considered to be achieved. “Prioritization” and “self responsibility” are achieved to a lesser extent. “Bed-side teaching” and “integrated seminars” are considered as good types of teaching. “Problem-based learning (PBL) sessions” and “subject-oriented lectures” are considered inferior to reach the specific goals in the traumatological education. Less favourably received was “computer based learning”. Required knowledge for board examinations is thought to be acquired best with “classical self study”. Second best way is thought to be the teachers of the HeiCuMed team. “Student learning groups” and “final exam” are considered equal, however, acquisition of knowledge is considered limited. Acquisition of knowledge “from students involved in the HeiCuMed sessions” and “compulsory attendance” was considered negative.Conclusions:The reform study system HeiCuMed in the field of traumatology is overall positively received. Improved motivation of students and self-competence are clearly visible.

Die Fixateur-externe-Osteosynthese distaler Radiusfrakturen nach dem Prinzip der Ligamentotaxis

Im Zeitraum vom 01. 01.1988 bis zum 31.10. 1991 wurden bei 73 Patienten mit komplexen, intraartikularen Radiusfrakturen vom Typ C 2 und C 3 die Indikation zur Fixateur-externe-Osteosynthese gestellt. Trotz der sechswochigen Di-straktion zeigten von den 40 nachuntersuchten Patienten 32 gute funktionelle und radiologische Ergebnisse. Die Wiederherstellung des volaren Kippwinkels gelang jedoch nur in 10% der Falle.