Results of Total Knee Arthroplasty with NexGen LPS-flex Implant Using Navigation System (Brain Lab): Results with a 5-year Follow-up

PURPOSE: To evaluate the clinical and radiological results of patients that underwent total knee arthroplasty (TKA) with a NexGen LPS-Flex implant using a Navigation system (Brain Lab). MATERIALS AND METHODS: Between January 2001 and December 2005, 55 knees in 46 patients which used the NexGen LPS-Flex implant with a Navigation system (Brain Lab) for primary TKA were clinically and radiologically evaluated after a minimum follow-up of 5 years. Evaluation included preoperative and postoperative range of motion (ROM), Knee Society Score (KSS), tibio-femoral angle and postoperative complications. RESULTS: Knee ROM was increased from 118.9degrees preoperatively to 126.9degrees at the last follow up. In addition, the preoperative flexion contracture improved from 6.5degrees to 1.8degrees postoperatively. The mean KSS and functional score were improved from 59.8 and 51.2 to postoperative scores of 86.4 and 85.2 respectively. The rate of appearance of radiolucency in X-ray was 21.8%. One case of superficial skin infection and one case of aseptic loosening were noted as complications but, did not require a revision surgery. CONCLUSIONS: TKA with NexGen LPS-Flex implant using Navigation system (Brain Lab) showed satisfactory improvement in pain and function, but more long term follow up will be needed to complete verification.

Simultaneous Reduction of Contralateral Malar Complex in Cases of Unilateral Zygoma Bone Fracture

PURPOSE: Reduction by simply assembling bones is recognized as treatment for a zygoma fracture. However, in patients who originally had a protruding zygoma, the fractured parts look like malarplasty after the edema subsides, giving a soft impression which patients notice. Thus, we created symmetry through simultaneous contralateral malar reduction in a unilateral zygoma fracture. METHODS: In this study, the patients who had surgery between July, 2008 and December, 2009 with admission were object. In 76 patients with a zygoma fracture, the patients with bilateral zygoma fractures were excluded. Among 48 patients who had a reduction only after a unilateral zygoma fracture, the patients hoping for a reduction of their rough protruding zygoma were analyzed with front cephalometry. The study progressed on 22 patients who had simultaneous contralateral malar reduction in a unilateral zygoma fracture with consent. After fixing the fracture, we did a straight zygoma osteotomy through a 1.5cm intraoral incision. After that, we created symmetry with a special ruler and fixed the broken zygomatic arch with a screw and plate. We evaluated the facial index and satisfaction with a statistical analysis before and after the surgery. RESULTS: In 22 patients, there was no reoperation except for 1 patient who had a zygoma fracture. None of the patients were treated for infection or hematoma. Two patients complained of paresthesia after the malar reduction operation, but this subsided in 4 months. Most of them were satisfied with the malar reduction, especially the women, and we obtained a better mid facial contour with decreased facial width(p<0.05). CONCLUSION: Existing zygoma fracture surgery focuses on anatomical reduction. However, we need to have a cosmetic viewpoint in fractures as interests of face contour arise. Thus, contralateral malar reduction got a 4.7 (range 0~5) from patients who had malar reduction surgery in our hospital. Although adjusting to all zygoma fractures has limitations, it can be a new method in zygoma fractures when there are limited indications of protruding zygoma and careful attention is given to patients' high demands.