[Halm-Zielke instrumentation in idiopathic scoliosis. Results in 25 consecutive patients with a minimum follow-up of 2 years].
OBJECTIVE
Halm-Zielke Instrumentation (HZI) was developed to eliminate the disadvantage of VDS-Zielke in terms of lack of primary stability and in order to simplify sagittal plane control. Since 1993 we study within a prospective clinical trial, whether HZI fulfills these demands.


METHODS
HZI is an anterior double-rod system with a two screw per vertebral body fixation. The longitudinal components consist of a threaded VDS-rod and a solid rod, which are attached to a hinge-conducted lid plate. 25 consecutive patients with idiopathic scoliosis and curves ranging from 36 degrees to 92 degrees were treated with HZI. The follow-up period ranges from 2 to 4 years.


RESULTS
Correction of the frontal plane within the instrumented levels averaged 71.4% and 70.4% postoperatively and at follow-up, respectively. Derotation averaged 51.7% and mean correction of the tilt of the lowest instrumented vertebra was 69.5% at final follow-up. Thoracolumbar kyphosis was present in 7 patients and always completely corrected. One implant related complication, a screw breakage 12 months postoperatively without adverse effects was noted. There was no case of pseudarthrosis. All patients were mobilized without any additional external immobilization in terms of a brace or cast and were allowed to go swimming for physio-therapeutical purposes immediately after wound healing.


CONCLUSIONS
This study proves that HZI is a primary stable implant to perform the Ventral Derotation Spondylodesis. The VDS-typical implant related disadvantages are eliminated. With this the period of rehabilitation is shortened by many months due to avoidance of cast and brace treatment.
Halm
H
H
Klinik für Wirbelsäulenchirurgie-Skoliozezentrum-Zentrum für Thoraxwanddeformitäten, Klinikum Neustadt/Ostsee.
Niemeyer
T
T
Halm
B
B
Liljenqvist
U
U
Steinbeck
J
J
D000293:Adolescent; D000328:Adult; D002648:Child; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000209:etiology*; D011446:Prospective Studies; D012600:Scoliosis / Q000209:etiology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation*; D016896:Treatment Outcome