Introduction: Obesity is often considered as a risk-factor for higher complication rates and worse clinical outcome of fusion surgery in the lumbar spine and is therefore sometimes not performed in obese patients despite relative indication for surgery. The goal of this study was to evaluate whether BMI is a predictive factor for clinical outcome after monosegmental fusion surgery in the lumbar spine.

Patients and Methods: The present study is a retrospective analysis of prospectively collected data in a consecutive series of patients.

Between April 2002 and April 2007, a total of 467 patients underwent monosegmental lumbar fusion in a single spine-center. Preoperatively and at 6 weeks and 1 year follow-up, SF36 and Oswestry-Disability-Index scores were collected. We excluded patients who underwent surgery due to infections, tumor and trauma, as well as revision surgeries, and all patients with incomplete datasets, so that 223 patients were included in the study. Of those patients, variables considered as risk-factors like age, BMI and the presence of diabetes mellitus were assessed from the medical records. A multiple regression model for those parameters and clinical outcome was cretated. Results: In an unadjusted model, BMI did not at all predict clinical outcome, in a multivariate model adjusted for baseline outcome values of SF36, Oswestry-Disability index and age, a slight trend towards negative correlation between BMI and outcome could be shown (p=0.06).

Conclusion: This study suggests that BMI alone is not a good predictor of clinical outcome of monosegmental lumbar fusion and that therefore this kind of surgery should not be withheld from patients only because of obesity.

Since total disc replacement (TDR) has broadened the spectrum of surgical treatment of degenerative spine diseases many comparison studies, particularly with interbody fusions (IF), have been done. Even though comparable results concerning functionality, radiologic results and subjective rating of life-quality have been presented, very few data about athletic activity before and after spine surgery exists.

Material and Methods: Between 1/2002 and 10/2006 181 patients had interbody fusions and 57 had a total disc replacement. Of 86 IF-patients and 25 patients with TDR we have complete data, which was collected in pre- and postoperative clinic and radiologic routine control with standardised questionnaires containing evaluation of level (frequency) and sort of sport. Patients are matched according to demographic data and preoperative activity beside the most important match of operation method.

Results: Patients with Total disc replacement show a later resumption of sports (19 weeks) than fusion patients (14 weeks), but more TDR patients (60%) achieve their preoperative level of sport than IF-patients (36%) do. Vice versa to the Fusion group in the TDR group more patients start a new sport after surgery than to stop one. Percentage of patients doing sports post- compared to preoperative is higher in both groups. Less patients having a TDR complain about technical limitations during practicing sports than fusion patients.

Discussion: Despite later resumption of athletic activity TDR seems to be the better surgical treatment of degenerative disc diseases in active patients and athletes due to overall higher sports levels. If long term results can keep up with short time follow ups has to be questioned.

Kyphoplasty is an efficient tool in the treatment of primary tumours (plasmocytoma) and osteolytic metastasis. Especially in plasmocytoma the current chemotherapy has increased life expectancy significantly. Therefore minimal-invasive stabilisation is not only a palliative treatment but really increases quality of life in those cases.

Kyphoplasty offers several special tools and techniques to lower the leakage rate which is especially high with other cementoplasty techniques in the osteolytic spine.

Materials and Methods: Prospective study of all vertebral tumours compared to osteoporotic fractures treated with kyphoplasty in 2004. 6 months follow up with VAS, SF36 and Oswestry score.

Results: In 2004 we performed 67 Kyphoplasties. 12 kyphoplasties were performed in tumour cases (5 plasmocytoma and 7 metastasis). No complications occurred during surgery and during hospital stay. Follow-up included 11 tumours (1 death during F/U) and 46 osteoporotic fractures. 1 patient was treated with combined decompression/kyphoplasty. The pain level (VAS) was significantly reduced in all cases within 2 days (osteoporotic group 2,2 – tumour group 5,4) and reached nearly the same result after 6 weeks which persisted for 6 months (osteoporotic group 1,6, tumour group 2,1). The SF 36/Oswestry Score improved accordingly in both groups. At 6 weeks and 6 months F/U no statistical difference in the scores was seen.

Conclusion: Kyphoplasty is a safe treatment method for osteolytic vertebral tumours with vertebral collapse. Clinically the results don’t differ from conventional cases. In cases with canal compromise, a combination with open techniques is possible. Special kyphoplasty techniques allow a reconstruction of the lytic wall and minimise leakage and cement dislocation. Significant improvement of life quality can be achieved offering the spine surgeon a valuable tool in the treatment of spinal metastasis.

Purpose: A complete collapse of osteoporotic vertebral fractures is difficult to treat. Restoration of vertebral height is very difficult, if ever possible. Kyphoplasty has been shown to restore vertebral compression fractures; however the best results are achieved in fractures without total collapse. Nevertheless some fractures develop osteonecrosis and pseudarthosis which can be easily seen on X-ray. For those cases we performed a retrospective study in order to evaluate the capacity of kyphoplasty in those difficult situations.

Methods: We analyzed the pre- and postoperative X-rays of vertebra plana treated between 2002 and 2005. Vertebral height (vh -anterior, middle and posterior) and kyphotic angle were measured with a digital imaging system. 2 independent examiners classified the preoperative X-rays into fractures with osteonecrosis/pseud-arthrosis (group 1) and without osteonecrosis (group 2). Statistical analysis with the non-parametric Mann-Whitney test was performed.

Results: Between 2002 and 2005 we performed 315 kyphoplasties. A total collapse of the vertebra (vertebra plana) was treated in 15 cases. Mean age 76 years, SD 5.2 years, average time of treatment after fracture 4 months. Osteonecrosis was persistent in 8 cases. The osteonecrosis group found a statistically significant higher degree of vertebral reconstruction (p < 0.013 - group 1: anterior vh 33%, middle vh 37,8%, posterior vh 19,1%; group 2: anterior vh 4,9%, middle vh 17,5%, posterior vh 1,8%). No significant difference was found in the analysis of the pre- and postop. kyphotic angle which could be due to the small sample size as the mean values are three-fold elevated in group 1 (p = 0.146, group 1: restoration mean 9,1° - maximum 18°; group 2: restoration mean 3,5° - maximum 13°).

Conclusions: Osteonecrosis is a positive predictive sign for the potential of vertebral reconstruction. Vertebral height can be significantly improved in those patients and the major changes of the kyphotic angle are possible. Even after 4 months, correction of the deformity is possible with kyphoplasty. However, without this sign, restoration of the vertebral height and correction of kyphosis is limited to rare cases.