title: [The rotationally stable screw-anchor with trochanteric stabilizing plate (RoSA/TSP) : First results in unstable trochanteric femur fractures].
abstract: BACKGROUND
  In unstable trochanteric fractures, the extramedullary rotationally stable screw-anchor (RoSA) combines the benefits of the load and rotational stability of the blade with the advantages of the screw (pull-out resistance, compression capability) in a single load carrier, and was designed to prevent femoral neck shortening by using an additional locked trochanteric stabilizing plate (TSP).
  
  
  OBJECTIVE
  The aim of the current prospective cohort study was the clinical evaluation of the RoSA/TSP system regarding the mechanical re-operation rate and the amount of postoperative femoral neck shortening.
  
  
  METHODS
  From September 2011 to January 2014 80 patients with unstable trochanteric fractures underwent internal extramedullary fixation with the RoSA/TSP (Königsee Implantate GmbH, Allendorf, Germany). Due to fracture stability and after induction of compression, additional long locked antitelescoping screws (AT, n = 1-4) were placed reaching the femoral head. Radiological (femoral neck shortening) and clinical re-examination of patients (n = 61) was performed 6-10 weeks and 6-10 months later.
  
  
  RESULTS
  In the 61 re-examined patients (76 %) femoral neck shortening was very low with 2 mm 6-10 months after operation. Re-operations occurred in 8 % (n = 6) and in 4 % (n = 3) as prophylactic surgical intervention. Whereas one-third (4 %) of re-operations occurred due to iatrogenic surgical problems from the first operation two-thirds of patients (8 %) had a re-operation due to delay of bone union (3× nonunion, 3 planned removals of AT-screws to improve healing). The in-hospital mortality was 3 % (n = 2).
  
  
  CONCLUSIONS
  The fixation of unstable trochanteric femur fractures using the RoSA/TSP in a first clinical setting led to a great primary stability, with significant advantages with regard to limited femoral neck shortening. However, the rigidity of the construct with its consequences regarding bone healing can be challenging for the surgeon. Nevertheless, in some cases of revision it could be beneficial for stability.
authors: Abteilung für Allgemein-, Viszeral- und Unfallchirurgie, RoMed Klinik, Bad Aibling, Deutschland.
authors: K-J
authors: KJ
authors: Maier
authors: Klinik für Unfall-, Hand- und Wiederherstellungschirurgie, Universitätsklinikum Gießen und Marburg GmbH, Marburg, Deutschland.
authors: B
authors: B
authors: Bücking
authors: Klinik für Unfall- und Wiederherstellungschirurgie, Uniklinik RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Deutschland.
authors: K
authors: K
authors: Horst
authors: Klinik für Unfall- und Wiederherstellungschirurgie, Uniklinik RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Deutschland.
authors: H
authors: H
authors: Andruszkow
authors: Klinik für Unfall- und Wiederherstellungschirurgie, Uniklinik RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Deutschland.
authors: F
authors: F
authors: Hildebrand
authors: Klinik für Unfall- und Wiederherstellungschirurgie, Uniklinik RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Deutschland. mknobe@ukaachen.de.
authors: M
authors: M
authors: Knobe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001860:Bone Plates; D001863:Bone Screws; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000295:instrumentation / Q000379:methods*; D018460:Fractures, Comminuted / Q000000981:diagnostic imaging / Q000601:surgery*; D006620:Hip Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000601:surgery; D012086:Reoperation; D013525:Surgical Instruments; D053441:Suture Anchors
keywords: Femoral neck shortening; Rotationally stable screw-anchor plate system (RoSA); Screw-blade combination; Trochanteric stabilizing plate (TSP); Unstable trochanteric femoral fracture