[Recurrent effusion and granulomatous synovitis following total knee arthroplasty in association with latex allergy]. / Rezidivierende Ergussbildung und granulomatöse Synovitis nach Knietotalendoprothesenimplantation bei Latexallergie.

An increasing number of articles report about allergic reactions in association with total knee arthroplasty. While most studies focus on allergic reactions to metallic components, few reports exist about reactions to bone cement or its ingredients. Allergy to natural rubber latex is a major occupational problem in the health care sector and a problem even in other occupations in which protective gloves are used. The allergic reaction to latex ranges from a minor skin rash to anaphylactic shock. Preventing exposure to latex is the key to managing and preventing this allergy. We report about a patient who developed recurrent effusion and granulomatous synovitis following total knee arthroplasty in association with latex allergy.

[A hinged external fixator for treatment of complex elbow joint injuries]. / Der Bewegungsfixateur zur frühfunktionellen Behandlung komplexer osteoligamentärer Verletzungen des Ellenbogengelenks.

BACKGROUND: The treatment of complex injuries of the elbow joint by a hinged fixator is a new concept of external transfixation with guided movement in a defined monocentric axis. Biomechanical investigations using cadaver specimens showed that the monocentric guidance ensures additional stability in these unstable osteoligamentous injuries, allows early functional treatment, and can be used in primary but also in revision surgery. PATIENTS AND METHODS: Between 1997 and 2004, 23 patients with complex fractures of the elbow joint were treated with a hinged monocentric external fixator after open reduction and internal fixation. The early functional treatment started 6.4 days (mean) postoperatively; the average range of motion (ROM) was 58 degrees. RESULTS: The early functional treatment using a hinged fixator resulted in a mean increase in the range of motion of up to 71 degrees within an average time course of 34.7 days. In 18 patients a significant increase in the ROM was seen; in 4 patients no improvement in the ROM could be achieved. Only one patient showed a decrease in ROM (5 degrees). Follow-up examinations after 10 months revealed a mean ROM of 88 degrees. CONCLUSION: In agreement with the literature, our results provide evidence that the use of a hinged monocentric external fixator in combination with early functional therapy results in an increase in the ROM and represents a beneficial device and concept in the treatment of complex injuries of the elbow joint.

Stiffness measurement of the neocallus with the Fraktometer FM 100.

INTRODUCTION: The assessment of fracture healing is subjective, and neither radiology nor manual examination allows a reliable determination of bone healing. Fracture healing control in the treatment of tibia shaft fracture with external fixator by a stiffness measurement system (Fraktometer FM 100) is known from clinical studies. The purpose of this study was to follow stiffness control at external fixator in healing of callotasis with the stiffness measurement system. MATERIALS AND METHODS: From 1994 to 1997 stiffness measurements with the described system (Fraktometer FM 100) were performed in the BG-Clinic Ludwigshafen to assess the healing course in 11 cases of callotasis at lower limb. RESULTS: In ten cases, regular healing could be followed by signal decrease; in one case, a persistent signal without tendency to decrease was able to reveal callotasis failure at an early point of time. The investigation could also show the importance of bending stiffness control. One case of late axis deformation after fixator removal occurred because of disregarding delayed bending signal decrease. CONCLUSION: Measurements of the external fixator's stiffness after callotasis can provide useful additional information for further treatment strategy.

[Kinematic investigations of the talocrural joint in human cadaver specimens. Basic studies for the development of a hinged fixator]. / Biomechanische Untersuchungen der Achsenkinematik an menschlichen Sprunggelenken Grundlagenuntersuchungen für die Entwicklung eines Bewegungsfixateurs.

To determine the specifications of a hinged fixator for the upper ankle joint, biomechanical investigations were performed on 20 human cadaver specimens and the talocrural axis was recorded by X-ray cinematography in all levels of the space. The results showed a medium variation of the axis in zero position (mean: 5.8 degrees ) from 3 degrees to 10 degrees in the anterior-posterior view. The span of the axis migration around zero position amounted to a minimum of 3 degrees and a maximum value of 10 degrees (mean: 7.2 degrees ). It could be ascertained that the axis kinetics does not move linearly in all cases. The talus rotation (the axle deviation from the sagittal plane) amounted to a minimum value of 2 degrees and a maximum value of 12 degrees (mean: 5.3 degrees ). In the transverse level, the axis kinetics was tracked by separate X-ray markings of the lateral and medial cortical of the talus in the zero point of the talocrural axis. The results were typical migration curves of the X-ray markings, demonstrating a ventral convex curve at the medial and lateral cortex. This migration of the cortex crossing point of the axis was geometrically entered in a coordinate system. The variance of the axis cortex crossing point at the medial cortical was X(M)=4.2 mm (min: 2 mm, max: 7 mm) and Y(M)=4.7 mm (2-7 mm), at the lateral cortical X(L)=3.7 mm (1-9 mm) and Y(L) =4.1 mm (1-8 mm). Regarding the clinical relevance for the development of a hinged fixator for the upper ankle joint, the results indicate that an external axis guidance of these axoids is not possible, but that an adjusted axis is necessary taking into consideration the values measured using ligamentotaxis.

Monitoring and healing analysis of 100 tibial shaft fractures.

BACKGROUND: We assessed the value of measuring biomechanical stiffness by assessing the fixator's external deformation as an objective means for monitoring fracture healing and determining the postoperative treatment regime, as compared to clinical and radiographic means of evaluation. PATIENTS AND METHODS: One hundred patients with tibial shaft fractures managed by unilateral external fixation had their fracture stiffness monitored. Stiffness was measured and clinical and radiological examinations were performed every 3-4 weeks. RESULTS: The time required for healing as indicated by stiffness measurement was an average of 2.5 weeks earlier than by radiological assessment. Eighty-two patients healed within 19 weeks (12.1+/-3.3 weeks) and ten patients in the following 6 weeks (24+/-4.3 weeks). Eight patients did not show an increase in fracture stiffness and received intramedullary nailing at a second operation. The average healing time was 11.3+/-4 weeks for type A, 13.1+/-3.6 weeks for type B fractures, and 15.1+/-5.9 weeks for type C fractures. The healing time for closed fractures was 11.3+/-3.2 weeks and for open fractures 14+/-4.9 weeks. CONCLUSIONS: The measurement of fracture stiffness allows the detection of patients at risk for nonunions. The healing time increased with increasing fracture gap size and was less in patients with younger age, less complex fractures, and lesser degrees of soft tissue damage.

[Treatment of complex elbow injuries by joint-spanning articulated fixator]. / Die Behandlung komplexer Ellbogenverletzungen mit einem gelenküberbrückenden Fixateur mit Bewegungsachse.

Biomechanical investigations in eight specimen elbow joints to test articulated external fixation showed correct extension-flexion joint position between 0 and 120 degrees. The central axis through the radial and ulnar condyles varies less than 3 degrees in total. X-ray cinematography showed correct articulation in all cases without subluxation. In six patients with persistent subluxation and complex fracture of the proximal ulna external fixation with an additional articulation was placed. All patients began with physiotherapy on the 3rd day after operation, the range of joint motion was 0-30-95 degrees in all cases, after 6 weeks 0-30-110 degrees. Additional articulated external fixation at the elbow joint can be an alternative treatment to long-term transfixation of the elbow in cases of complex injury.

[Diagnostic and incidence of the rupture of the posterior cruciate ligament]. / Diagnostik und Inzidenz der Verletzungen des hinteren Kreuzbands.

The purpose of this article is to evaluate the incidence and to give a general review of the examination of the posterior ligament complex. At least ca. 8-10 % of all severe ligament injuries concern the posterior cruciate ligament, which means, that an estimated 4,000-5,000 Germans suffer a PCL rupture every year. Motor-vehicle accidents are the most common cause of the injury, but sports-related traumas (football, skiing) have increased in recent years. The high number of high-energy mechanisms involved (up to 90 %), cause ligament ruptures often to be associated with other injuries, especially fractures of the femur and tibia head. In polytrauma patients PCL ruptures are frequently recognized very late, because the possibility of this kind of injury is often not considered during the clinical examination. The same holds for the diagnosis of monotrauma patients. The initial step in the evaluation is to obtain a thorough history (including the mechanism of injury) and to perform a physical examination. The instability after a PCL rupture may present as an ACL rupture, because the anterior drawer test seems to be positive. The anterior/posterior drawer test must be assessed with other evaluation procedures to distinguish between anterior und posterior instabilities. The posterior sag sign, the quadriceps active test or the reversed pivot-shift may indicate a PCL rupture. A correct roentgenogram can reveal an avulsion of the tibia and can prove posterior instability due to a posterior translation of the tibia. A quantitative examination (clinical or X-ray) of the instability and the indication of combined injury of the posterior cruciate ligament and the posterolateral complex are necessary for the therapeutic decision (operative/conservative). A rupture of the PCL may occur occasionally as a result of a luxation of the knee (reduced spontaneously) before the medical evaluation. A thorough neurovascular examination is essential. Magnetic resonance imaging can be important to the diagnosis of an acute injury, but it is not essential for the choice between operative and non-operative treatment. Arthroscopy has been found to have a high degree of accuracy in the diagnosis of ligament ruptures of the knee, but it is still an operative treatment, so that it can only be used if an operation of repair or reconstruction is planned anyway. Before operative treatment of chronic complex instability, potential osseous abnormalities (varus morphotype) must be revealed; in case of uncertainty, an X-ray control is necessary.

[Augmented repair as therapy of fresh injury of the posterior cruciate ligament]. / Therapie der frischen Verletzung des hinteren Kreuzbands mit augmentierter Naht.

The discussion about the therapy of the posterior cruciate ligament persists. Conservative treatment, augmented repair, and reconstruction with autografts are discussed. From 1993 to 1997, 49 patients with posterior cruciate ligament rupture had repair Trevira ligament augmentation of 3 mm. There were 21 isolated and 28 combined ruptures. In 5 cases bony avulsions were refixed by screw or additional hook plate. Investigation of 36 patients, in 15 cases with isolated ligamentous ruptures was made. Osseous avulsion had good results in all cases. Isolated posterior cruciate ligament rupture showed good stability in 7 of 15 cases and instability of 2 + in 8 cases. The medial range Lysholm score was 76.8 (+/- 21.6), the OAK score showed 2 very good and 5 good results, 3 fair and 5 bad results. Using the IKDC score led to 3 very good and 4 good results, 2 fair and 6 bad results. Using subjective criteria, 10 patients described results as very good or good, 2 fair and 3 bad. Posterior cruciate ligament rupture with additional knee injury or fracture of the leg showed bad results in 60 % of cases, and good or fair results in only 40 %. We think augmented repair of fresh injury of the posterior cruciate ligament can be used as an alternative therapy to reconstruction with autograft.

[Comparative studies on the ingrowth behavior and the bone adhesion of various implant materials. An animal experiment]. / Vergleichende Untersuchungen über das Anwachsverhalten und die Knochenhaftung verschiedener Implantatwerkstoffe. Eine tierexperimentelle Untersuchung.

Each of 36 mongrel dogs received implants of the following six materials: methyl methacrylate, carbon fibre composite, aluminium oxide-ceramic, titanium alloy, pure titanium and hydroxylapatite (HA). Test rods 7 mm in diameter were used to perform a push-out test, and discs with a diameter of 25 mm and a thickness of 5 mm were used for a plane traction test. The animals got a fluorochrome labelling and were harvested 8 weeks after operation. The results of the push-out test were a stability of 3.6 N/mm2 for HA and very low values for all the other materials, while the plane tension test showed a stability of 1.6 N/mm2 for the HA discs and values that were not even measurable for all the other materials. The interface of HA and the bone could not be separated by mechanical forces; usually the bone or the ceramic material fractured beneath the interface, so that the real stability of the interface must be rated very high. Light and fluorescence microscopy revealed a close bone connection for HA and only partial connections for the other materials. HA-coated materials may have a future in orthopaedics surgery.

[Semirigid plate osteosyntheses using absorbable polymers as temporary implants. II. Animal experiment studies]. / Semirigide Plattenosteosynthesen unter Verwendung absorbierbarer Polymere als temporäre Implantate. II. Tierexperimentelle Untersuchungen.

Polylactide-l test rods showed an initial stability of 130 N/mm2 in the three-point bending test; the stability decreased after implantation in the dorsal muscle of the rat within 5 weeks to about half the initial value. The copolymer materials showed less initial strength, and the stability decreased under the same conditions much earlier. All materials showed good tissue compatibility. After a transverse section of the beagle radius was stabilized with plates and screws out of polylactide-l, a delayed bony union with callus formation was observed.

[Semirigid plate osteosyntheses using absorbable polymers as temporary implants. I. Introduction, chemical composition and material-related studies]. / Semirigide Plattenosteosynthesen unter Verwendung absorbierbarer Polymere als temporäre Implantate.

Possible indications for the use of biodegradable implants are presented and the chemical compounds in question are briefly described. The results of a laboratory investigation to determine mechanical stability, tensile strength and molecular weight are reported, in order to characterize the polymers and co-polymers of the lactide under study.