The avulsion fracture of the V-th metatarsal and Jones fractures often show delayed and non-union. The tension belt osteosynthesis shows often soft tissue problems due to the thin soft tisshe covering. A new minimal invasive method with the 3,5mm XXS nail and the clinical results are presented.

Percutaneously the fracture is reduced with a K-wire as a joy stick. This or if the direction needed is different a second K-wire as guide is introduced and with a canulated 3,5 mm drill the place for the nail is prepared. Proximal and distal to the fracture one threaded wire locking and fracture compression through the nail (proximal longitudinal holes) are performed.

77 patients with a XXS nail fixation of MT V fractures were treated from July 1999 to Jan.2006. Clinical and radiological re-examination at 1 to 6 years were performed. The AOFAS was 22 pre- and 96 postoperatively. No pseudarthrosis but in 53 patients implant removal was done in part due to local discomfort. This was strictly correlated to the length of the threaded wires to the bone surface. 95% reached pretrauma activity levels. Satisfaction was 9 from 10 points.

The XXS nails allow a percutaneous stable fixation of the avulsion and Jones fractures of the V-th metatarsus. The complication rate is low.

Distal radius fractures are typical and frequent fracture of elderly woman with reduced bone density. Thus implant fixation is more difficult. Dorsal and radial comminution are frequent in these patients and so reduction and angle stable osteosynthesis needed. The angle stable plate, often also multidirectional is today the most common stabilisation device. Because of the introduction of bulky and bended implants as the Micronail or Targon DR wich require difficult opening of the bone with awles we decided to test the XS radius nail witch is a 4,5mm or 3,5mm straight nail and witch is introduced after guide wire placement and over drilling with a canulated drill of the same diameter. It is locked parallel to the joint in 3 different directions with angular stability with threaded wires.

Methods 16 radius sawbones were osteotomised corresponding to a A3 Fracture and stabilised with a angle stable plate (8) and XS nail (8). 1000 alternating load cycles from 20–200N were performed and the deformation was registered. Also a FE analysis with the MSC Patran/Marc softwere were performed.

Also the calculated deformation in the FE study was 20% lower. Also deformation amplitude was lower with 0.31mm compared to 0.42mm in the plate group. The differences however were not significant.

Both devices show good biomechanical results. The XS nail has the advantage of mainly intraosseus position, simple operation technique with introduction over a guide wire from the proc. Styloideus radii and over drilling with a canulated drill of the same size. The exposure of the N rad. superf. must be performed. First clinical evaluation is presented.

Due to the results we developed a anatomically adapted XS radius nail. The results of the first 100 patients are presented.

Clinical Problem

Pilon fractures and distal metaphyseal fractures of the tibia are associated with a high rate of soft tissue and bone healing problems.

We started to use the XS and XS nail as minimal invasive procedure for the management of these fractures in July 2000 first for the fibula and since for the fibula and pilon itself but extended metaphseal comminution are contraindication for the XS nail.

Because of soft tissue problems and higher loading capacity of intramedullary implants the XS Nail was also used for ankle fracture osteosynthesis but as in all articular fractures with open reduction,