Morphometrische Analyse zur Funktion eines innovativen, individuell anpassbaren Kunststoffimplantats für die Stabilisierung proximaler Humerusfrakturen Eine anatomische Studie

2019 wurden in Deutschland insgesamt 61.606 proximale Humerusfrakturen erfasst. Die Inzidenz pro 100.000 Einwohner beträgt 90,8 und zeigte in den Jahren 2009 bis 2019 eine Zunahme von 10%. Zur Versorgung der proximalen Humerusfraktur sind neben der konservativen Therapie im Bereich der operativen Behandlung verschiedene rein metallbasierte Osteosynthesetechniken beschrieben. Im Rahmen dieser anatomischen Studie wurde die Anwendung eines neuartigen, intramedullär platzierten, photodynamischen Polymers (IlluminOssTM) hinsichtlich der Anwendbarkeit untersucht. Präparate des proximalen Humerus wurden vermessen und Knochen sowie Markraum freipräpariert und gesäubert. Die äußeren Dimensionen wurden bestimmt, nachfolgend erfolgte eine Osteotomie im distalen Schaftbereich. Retrograd wurde ein Dacron-Ballon eingeführt welcher mit einem lichtempfindlichen Monomer aufgefüllt wurde. Die Positionierung und Auffüllung wurde radiologisch kontrolliert. Unter Applikation einer Lichtquelle mit bestimmter Wellenlänge erfolgte die Polymerisation und damit die Aushärtung des Monomers. Neun weibliche und sechs männliche Präparate (Durchschnittsalter 83,7 Jahre) wurden nach entsprechender Befüllung in die Auswertung einbezogen. Es erfolgte die Anfertigung computertomografischer Schnittbilder. In der semiquantitativen Auswertung zeigte sich bei der Entfaltung des Ballons eine weitgehende Auffüllung des epi- und metaphysären Anteils des proximalen Humerus. Die 15 Einzelimplantate zeigten eine Übereinstimmung hinsichtlich ihrer Ausformung mit in Relation zum Gesamtvolumen der Auffüllung nur geringen Auffüllungsdefekten. Im Schaftbereich fand eine nahezu vollständige Auffüllung des Markraumes statt. Die dreidimensionale Darstellung des Implantats zeigte eine auch für die chirurgischen Techniken relevante Augmentationsmöglichkeiten des beim alten und hochaltrigen Patientenkollektiv rarefizierten spongiösen Knochens in Epi- und Metapyhse des proximalen Humerus. Aufgrund des Kunststoffcharakters des intramedullären Implantates ist die additive Instrumentierung sowohl von Humeruskopf als auch von Humerusschaft mit gebräuchlichen Osteosynthesemitteln möglich, sodass die Kombination der beiden Verfahren in der klinischen Versorgung möglich ist und weiter untersucht werden sollte. Die hier vorliegende Untersuchung bezieht sich auf alte und hochaltrige Oberarmknochen und kann dementsprechend nicht auf die Situation bei jüngeren Kollektiven übertragen werden

Treatment of chronically unreduced complex dislocations of the elbow

Chronic dislocation of the elbow is an exceedingly disabling condition associated with severe instability, limitation of elbow function and significant pain. Due to the potentially conflicting goals of restoring elbow stability and regaining a satisfactory arc of motion, successful treatment is a challenge for the experienced trauma surgeon. We report our treatment strategy in three patients suffering from chronically unreduced fracture-dislocations of the elbow. The treatment protocol consists of in situ neurolysis of the ulnar nerve, distraction and reduction of the joint using unilateral hinged external fixation and repair of the osseous stabilizers. A stable elbow was achieved in all patients, without the need of reconstruction of the collateral ligaments. At final follow-up, the average extension/flexion arc of motion was 107° (range, from 100° to 110°). The average MEPI score at follow-up was 93, and the average DASH score was 19. This is a promising treatment protocol for the treatment of chronically unreduced complex elbow dislocations to restore elbow stability and regain an excellent functional outcome

Photodynamic intramedullary bone stabilization of pathological fractures

Pathological fractures of long tubular bones are stabilized with conventional implants. Essentially, plates and intramedullary nails are used for stabilization and are two different techniques, which compete with each other with respect to the surgical treatment. A large number of such means of osteosynthesis are commercially available but are primarily focused on acute fractures in otherwise biologically healthy bones. The pathological fracture or the treatment of impending pathological fractures due to metastatic osteolysis differs from the treatment of healthy bones in some fundamental aspects. The characteristics of pathological fractures make the development of new technologies that meet the specific needs of both the patient and the surgeon desirable. A new approach in treatment is stabilization of internal long bone fractures by the use of a cylindrical balloon implant, which is introduced into the bone via a small proximal or distal hole and then filled and expanded to a much larger diameter with a liquid monomer. The curing process is initiated with the application of blue light forming a rigid implant by polymerization (IlluminOss (TM)). Many of the well-known disadvantages of conventional implants can be eliminated with this technology. Specifically, with respect to the irregular shape of the natural medullary canal it is possible to completely fill the medullary canal of the tubular bone. The filling of the canal provides torsional stability without the use of interlocking screws. Similarly, the use of the balloon technique enables minimally invasive surgery and furthermore permits the additive use of conventional metallic plates whenever necessary. The new balloon techniques show high primary stability in the treatment of pathological shaft fractures. In particular cases, the addition of a supplemental plate osteosynthesis is recommended

Osteoporotic bone fractures: intramedullary augmentation and hybrid osteosynthesis

The increasing number of people who are living longer and have a far more active lifestyle is inevitably associated with greater numbers of fractures. Stabilization of these fractures in older patients with plates and screws is complicated by fragile bone substance, especially in osteoporotic bone, since osteosynthesis with a conventional plate depends exclusively on the holding power of the screws. Therefore, treatment requires new stabilization technologies designed for these specific tasks. A small diameter polyethylene terephthalate (PET, Dacron (R)) balloon is delivered in a minimally invasive fashion and placed within the canal, transversing the fracture. Once positioned, the balloon is expanded with a liquid monomer to fill the medullary canal. The liquid monomer is then rapidly cured using visible blue light, forming a patient-customized intramedullary implant that stabilizes the entire length of the bone in contact with the implant. The described intramedullary implant can be easily drilled in any position or location, providing a substantial increase in screw holding power. Thus, a major advantage of the technique is the possibility to augment the newly formed balloon nail with a conventional plate and screws at the primary stabilization or at any later time

Mallet finger: a simulation and analysis of hyperflexion versus hyperextension injuries

The goal of this study was to simulate the mechanisms of hyperflexion and hyperextension injuries of the distal interphalangeal (DIP) joint of the hand and to analyze the resulting extensor tendon injury patterns. The hypotheses were raised that hyperflexion trauma leads to a plastic deformation of the extensor tendon aponeurosis, with or without a small bony avulsion fragment but without joint surface involvement, and that hyperextension injuries can create a shear fracture of the dorsal lip of the distal phalanx, without injury to the extensor tendon aponeurosis. Loading was applied with a swinging pendulum impacting the distal phalanx in 103 human specimens in either an extended or flexion position. After loading, injury patterns were analyzed radiologically and histologically. There was evidence that hyperflexion trauma leads to a plastic deformation or rupture of the extensor tendon. Bony tendon avulsion was evident in 12.2 % of cases. With hyperextension, the extensor tendon remained intact in all cases, but there were large fracture fragments involving the articular surface in 4.1 % of cases. The results of the study show that force on the flexed joint leads to overstretching of the extensor tendon, and to an associated dorsal bony avulsion with intact joint line. Force applied to the joint in extension can lead to a bony dorsal edge fracture with articular involvement and with it, a palmar DIP joint capsule rupture. The results illuminate a direct correlation between the mechanism of injury and the pattern of injury in the clinical picture of mallet finger

Effective management of bone fractures with the IlluminOss® photodynamic bone stabilization system: initial clinical experience from the European Union registry

The IlluminOss® system (IS) uses a light-curable polymer contained within an inflatable balloon catheter, forming a patient customized intramedullary implant. A registry was established in Germany and The Netherlands to prospectively collect technical and clinical outcomes in patients treated with IS for fractures of the phalange, metacarpal, radius, ulna, distal radius, fibula, clavicle and/or olecranon. Humeral, femoral, tibial and pelvic fractures were included under compassionate use. Procedural success included successful placement of the device at the target fracture site and achievement of fracture stabilization. Clinical and radiographic assessments were made postoperatively through 12 months. One hundred thirty two patients (149 fractures) were enrolled with most fractures (85%) resulting from low-energy trauma. Simple fractures predominated (47%) followed by complex (23%) and wedge (16%) fractures. Procedural success was achieved in all patients and no implants required removal or revision. Normal range of motion was realized in 87% of fractures. Radiographically, there was substantial cortical bridging, total dissolution of the fracture line, and complete fracture healing. Across a variety of fracture types, the IS provides a safe and effective approach for rapid healing and functional recovery