RESUMO
BACKGROUND: Both nonoperative and operative treatments for spinal metastasis are expensive interventions. Patients' expected 3-month survival is believed to be a key factor to determine the most suitable treatment. However, to the best of our knowledge, no previous study lends support to the hypothesis. We sought to determine the cost-effectiveness of operative and nonoperative interventions, stratified by patients' predicted probability of 3-month survival. METHODS: A Markov model with four defined health states was used to estimate the quality-adjusted life years (QALYs) and costs for operative intervention with postoperative radiotherapy and radiotherapy alone (palliative low-dose external beam radiotherapy) of spine metastases. Transition probabilities for the model, including the risks of mortality and functional deterioration, were obtained from secondary and our institutional data. Willingness to pay thresholds were prespecified at $100,000 and $150,000. The analyses were censored after 5-year simulation from a health system perspective and discounted outcomes at 3% per year. Sensitivity analyses were conducted to test the robustness of the study design. RESULTS: The incremental cost-effectiveness ratios were $140,907 per QALY for patients with a 3-month survival probability >50%, $3,178,510 per QALY for patients with a 3-month survival probability <50%, and $168,385 per QALY for patients with independent ambulatory and 3-month survival probability >50%. CONCLUSIONS: This study emphasizes the need to choose patients carefully and estimate preoperative survival for those with spinal metastases. In addition to reaffirming previous research regarding the influence of ambulatory status on cost-effectiveness, our study goes a step further by highlighting that operative intervention with postoperative radiotherapy could be more cost-effective than radiotherapy alone for patients with a better survival outlook. Accurate survival prediction tools and larger future studies could offer more detailed insights for clinical decisions.
Assuntos
Neoplasias da Coluna Vertebral , Humanos , Neoplasias da Coluna Vertebral/cirurgia , Análise Custo-Benefício , Análise de Custo-Efetividade , ProbabilidadeRESUMO
OBJECTIVE: To identify factors that influence shoulder balance and to determine whether a model can be made to predict shoulder balance after corrective surgery. METHODS: This is a retrospective study in which we examined the records of with adolescent idiopathic scoliosis (AIS) patients who underwent single posterior spinal correction and fusion using all pedicle screws with derotation in our institution between January 2008 and June 2010. For the radiographic outcome measurement, we measured the preoperative lumbar curve, the main thoracic curve, and their difference (L_TH_D), and the degree of correction of the lumbar curve, the main thoracic curve, and their difference (c_L_TH_D) to evaluate their influence on postoperative shoulder balance. The preoperative flexibility of the proximal non-fusion curve on the immediate postoperative tilt of the upper endplate of the uppermost vertebra of fusion segments (Up_FuS) was used to evaluate and predict the shoulder balance at follow-up. RESULTS: For patients who had shoulder balance at follow-up, the average balance time was 7.1 months, and in most of them, balance was detected within 12 months. The main thoracic curve has the greatest influence on preoperative shoulder tilt and correction of the main thoracic curve has the greatest influence on the postoperative alteration in shoulder balance. To evaluate the influence on the preoperative shoulder tilt, the lumbar curve must be larger than the main thoracic curve both pre operatively and postoperatively. If the preoperative flexibility of the proximal non-fusion curve on the immediate postoperative Up_FuS includes the horizontal line (With Horizontal group), shoulder balance can be ensured. The postoperative Up_FuS can be evaluated based on the preoperative Up_FuS and the degree of correction of the lumbar and main thoracic curves. CONCLUSION: Shoulder balance can be ensured in patients in the With Horizontal group after surgery. If the preoperative Up_FuS and the degree of correction of the main thoracic curve and the lumbar curve are considered in the preoperative plan, the desired postoperative Up_FuS can be achieved, ensuring shoulder balance at follow-up.