Less-invasive-stabilizing-System (LISS)

Zusammenfassung

In einer prospektiven, nicht randomisierten Studie wurden zwischen Februar 1997 und September 1998 29 frische distale Femurfrakturen mit dem LIS-System versorgt. In die Nachuntersuchung wurden 29 Frakturen eingeschlossen. Die durchschnittliche Nachuntersuchungszeit betrug 6 Monate (1,5–16 Monate). Postoperativ kam es in 1 Fall zu heterotopen Ossifikationen mit Einschränkung der Kniegelenkbeweglichkeit, in 1 Fall zu einer tiefen Beinvenenthrombose mit Lungenembolie und in 3 Fällen zu tiefen Infekten, davon 2-mal als Folge offener Frakturen. In 2 Fällen kam es zu Schraubenausrissen. Die Zeit bis zur knöchernen Durchbauung betrug durchschnittlich 3,1 Monate (2,5–4,5 Monate), die Zeit bis zur Vollbelastung 3 Monate (1,5–5 Monate). Die Kniegelenkbeweglichkeit war in 15 Fällen – mit einer Nachuntersuchungszeit >3 Monate – 121° (mindestens 20°, maximal 140°). Der Lysholm-Score konnte für 9 Patienten ermittelt werden und ergab im Durchschnitt 67,5 Punkte (48–92 Punkte), der Neer-Score 69,8 Punkte (49–88 Punkte). Die Anwendung des LISS ermöglicht eine komplikationslose Ausheilung ohne Notwendigkeit der Knochentransplantation.

Abstract

In a prospective nonrandomized study conducted between February 1997 and September 1998, 29 displaced fractures of the distal femur were stabilized with an angular stable interlocking plate system (Less Invasive Stabilization System, LISS) designed for minimally invasive placement. The average age of these patients was 54 (range 20–92) years, and they were followed up for a mean of ¶6 months (1.5–16 months). Postoperative complications included heterotopic ossification (HO) limiting knee motion (1 case), deep thrombosis with pulmonary embolism (1) and deep infection (3 cases). Implant- and technique-related complications included proximal screw pull-out in the first 2 months after injury in 2 cases, which was treated by proximal screw exchange. In a 37-year-old woman with an increased antetorsion angle of 32° (internal rotation deformity) postoperatively a rotational correction was performed. Time to fracture healing averaged 3.1 (range 2.5–4.5) months in 23 cases. Time to full weight-bearing averaged 3 (range 1.5–5) months. The Lysholm score was available for 9 patients, and the mean calculated for these patients was 67.5 points (range 48–92), while the Neer (28) score for 9 patients with follow-up of more than 1 year averaged 69.8 (range 49–88) points (1 failure, 3 unsatisfactory, 4 satisfactory, 1 excellent result). The use of the LISS applied for distal femoral fractures with a correct technique led to uneventful bony healing with no necessity for the additional morbidity of a bone graft.