header advert
Results 1 - 3 of 3
Results per page:
Applied filters
Include Proceedings
Dates
Year From

Year To
Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 127 - 127
1 May 2011
Hoffmann F Jovanovic M Muschik M
Full Access

Introduction: With ceramic on ceramic bearing surfaces in total hip arthroplasty audible noise is a frequently documented problem. With increasing head size, there is less chance of component-on-component impingement and therefore a decreased risk of chipping, breaking and maybe noise occurrence.

Material and Methods: Prospective multicentre follow-up study of n=149 cases (91 males and 58 females). All patients were treated with either 32 or 36mm ceramic on ceramic articulation (Bionit®) in combination with the non-cemented modular pressfit cup seleXys® (Mathys Ltd Bettlach, Switzerland). There were n=4 patients with bilateral surgery. 56 patients received a 32mm head whereas 93 patients were treated with a 36mm head. In the group with 32 mm head diameter 79% were women, whereas in the 36 mm group only 16% were women. Patients were operated between December 2005 and January 2007. The mean age at surgery was 67.2 years (range, 46.3 – 86.4 years). Mean body mass index was 28.0 kg/m2 (range, 17.1 – 45.4 kg/m2). Patients were followed clinically and radiographically at three and six months, then after one and two years.

Results: 5 patients died and 2 patients were lost to follow-up. Only one patient reported squeaking noise immediately after the operation. At the one year follow-up the patient reported a feeling of subluxation and the noise turned into a clicking. The patient had to be revised after 14 months with a polyethylene inlay. No other revisions had taken place.

Patients with femoral heads of 32 mm and 36 mm diameter had excellent clinical results after 2 years follow-up for flexion angle, range of motion and Harris Hip Score. The Harris Hip Score increased from a pre-operative mean of 48.7 points to 93.5 points. Hip flex-ion increased from 91° to 113°. The Visual Analogue Scale for pain decreased from 6.7 to 0.9 and VAS for satisfaction increased from 3.2 to 9.3.

Conclusion: Compared to other studies the occurrence of noise and resulting revision procedures is very low. We assume that the insertion of bigger heads may reduce this problem and simultaneously allow the patient a better range of motion. The non-cemented modular cup combined with a ceramic inlay and a ceramic femoral head is a safe implant with excellent clinical results after two years.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 325 - 325
1 Mar 2004
Muschik M Schlenzka D Yrjšnen T
Full Access

Aims: To determine whether in operatively treated scoliosis patients loss of correction after implant removal for late infection can be avoided by reinstrumentation.

Methods: A retrospective review of 937 scoliosis patients treated by instrumented posterior fusion. Forty-þve (5%) developed late infection 2.9±1.7(0.5–8.0) yrs p.op. They were treated either by implant removal alone (HR, n=35) or by implant removal, re-instrumentation and augmentation of fusion (RI& F, n=10). Pseudarthrosis was found in 5 patients. Wound healing was uneventful in all patients of both groups after revision. There was no difference in mean Cobb angles between the groups neither before initial scoliosis operation nor before the revision.

The mean follow-up time after revision was 4 years. Results: Radiographically, there was a signiþcant loss of correction after revision operation. At the time of reoperation mean curve correction was 40.4%, being 28.8% at follow-up (p< 0.05).

There was a signiþcant difference in the radiographic outcome between the two revision techniques: In the RI& F-Group, the þnal thoracic Cobb angle correction. was 45.1% as compared to 20.8% in the HR-Group (p=0.03).

Conclusions: One-stage hardware removal and re-instrumentation is a safe procedure and prevents loss of correction in the treatment of late infection after posterior instrumentation and fusion for scoliosis.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_II | Pages 126 - 126
1 Jul 2002
Muschik M Schlenzka D Kupferschmidt C
Full Access

The goal of the present study is to investigate if one of the two dorsal operative procedures (rod-rotation versus translation technique) leads to a better radiographic correction of idiopathic adolescent thoracic scoliosis after operative treatment.

The operative technique in scoliosis surgery introduced by Cotrel and Dubousset attempts to achieve an improvement of the sagittal profile and a derotation of the vertebrae, in addition to a correction of the main curvature of the scoliotic spine by rotation of the convex-side rod (rod-rotation). The technique of segmental correction was described by Luque. Correction of the scoliosis is performed after fixation of each vertebral body with wire cerclages, followed by segmental correction of the deformed spine. The Universal Spinal System was introduced and an operating technique was developed to take advantage of the principle of segmental correction of scoliosis (translation technique).

The radiographic outcomes in two groups comprising a total of 69 adolescent patients treated for idiopathic thoracic scoliosis with dorsal instrumentation by the use of a unified implantation system (Universal Spinal System) were compared retrospectively by an independent observer. In 30 patients an intraoperative correction of the scoliosis was performed by translation technique (translation group) and in 39 patients the correction was achieved by Cotrel-Dubousset instrumentation (rod-rotation group). The mean follow-up interval was 40 months with a minimum of 12 months. The preoperative radiographic measurements of the scoliotic spines showed no significant differences between the two groups.

In both patient groups, the thoracic primary curve, lumbar secondary curve, and apical rotation of the thoracic curve were improved by the operation. The thoracic primary curve was corrected from 50 6° to 24 7° (p< 0.01) in the translation group and from 54 11° to 22 11° (p< 0.01) in the rod-rotation group. The extent of the correction of the thoracic curve was significantly greater in the rod-rotation group than in the translation group (59% versus 52% correction; p< 0.01). Thoracic apical rotation was corrected from 21 ± 9° to 16 ± 10° (p< 0.01) in the rod-rotation group and from 19 ± 9° to 17 ± 7° (p< 0.05) in the translation group. Lumbar apical rotation and the sagittal profile were unchanged in both groups.

Based on the results of this study with a small number of patients, the ability of the translation technique to correct the thoracic major curvature seems to be less than that of the rod-rotation technique. No differences are to be expected in the correction of the lumbar minor curvature or of the rotation of the thoracic apex. Neither procedure is expected to influence the sagittal profile or lumbar rotation.