Abstract
Introduction: The Taylor Spatial Frame (TSF) is a circular external fixator based on a hexapod system consisting of two carbon fiber rings connected with six telescopic struts. In conjunction with a software program the TSF allows for correction of deformities in 6 axis. After completion of the computer generated distraction plan a residual program can be used to correct any residual malalignment. Although the TSF received marketing clearance in 1997 and is used in specialized centers around the world, there is, up to date, only one MEDLINE report of two cases treated with the TSF. We present the results of 48 cases of limb lengthening and/or deformity correction using the TSF frame.
Patients and Methods: Between June 1999 and Septem-ber 2002 we implanted a total of 102 Taylor Spatial Frames (TSF). Only cases with a minimum follow up of 6 months after removal of the frame were included in our retrospective study. Thirty-six patients with a total of 48 TSF fixators met the inclusion criteria. The 23 female and 13 male patients had a mean age of 16 years (range:4-49). Eleven cases showed a post-traumatic deformity,13 cases a metabolic, 9 a congenital, 8 a osteodysplastic deformity and 7 showed various underlying pathologies. Seven TSF frames were implanted on the femur, whereas the remaining 41 frames were applied to the tibia.
Results: In 25 cases lengthening was the main treatment goal and in 23 cases the TSF was applied for angular or rotational deformity correction. The mean lengthening achieved in the group of patients treated was 40 mm (range: 20-70) and a mean healing index of 52.73 days/cm (28-105). In the patients who were treated to correct a deformity, the mean healing index was 159.69 days/cm (88-276). The highest mean healing index (178.91 days/cm) was found in patients where a metabolic disease was the underlying pathology, whereas patients treated for congenital lateral longitudinal defects showed the lowest mean healing index (53.25 days/cm). Complications included a superficial pin infection occurred in 66.6 % of the cases. There was no case of deep infection . Further complications were temporary postoperative sensory disturbance in 2 cases, premature consolidation of the fibula requiring re-oste-otomy in 2 cases, femoral fracture after removal of the frame in one case and dislocation of the frame with the need to change the position of a pin in another case. There were no hardware associated complications. A residual program was generated in 15 cases, 3 cases needed 2 and one case 4 residual programs to achieve the desired correction.
Conclusion: The healing index varied widely within our patient population. We assume that the healing index is not applicable to the correction of angular or rotational deformities with a lengthening less than 2 cm. The possibility of performing residual correction in all axis without the need to change the frame setup is a main advantage of the TSF and is very time saving during follow up examinations. Preoperative frame assembly is easy and fast compared to the standard Ilizarov system. A computer printed day-by-day prescription of strut adjustments makes it easy for the patient to perform the distraction and augments patient compliance.
Local Host: British Society for Children’s Orthopaedic Surgery. Conference Theme: Congenital Deficiencies of the Lower Limb. These abstracts were prepared by A.Catterall.
