Objectives: Description of early results using a new modality in musculoskeletal oncology.

Introduction: Radiofrequency as a malignant tumor ablative modality has been employed during the last decade in liver tumors. Extra-hepatic application in malignancies is new and its indications are not precisely defined. It has been used for more than ten years for osteoid osteoma ablation. Radiofrequency allows destruction of a precise sphere around the application tip. Ablation efficiency is monitored by the change in tissue conductance following tissue necrosis.

Methods: 10 patients scheduled to undergo limb sparing surgery were included. During the pre-operative angiography and embolization, tumors were treated by radio-frequency ablation. The precise location of the needle electrode was defined by real-time ultrasonography. The relation of the needle tip to large blood vessels was monitored by comparison of ultrasonography to angiography. Thus, precise ablation of the tumor tissue was possible without risk to the neurovascular bundle.

Results: Tumor necrosis was uniform in the center of the ablative sphere and declined to 60 percent in the periphery. No complications were encountered.

Discussion: This method appears to allow further shrinkage of the tumors prior to limb sparing surgery. This technique is rapid and does not require delay of surgery, as does isolated limb perfusion or neo-adjuvant chemotherapy. The procedure can be performed in sedated patients, thus obviating the need for general anesthesia prior to limb sparing surgery. It can be employed in areas were isolated limb perfusion is not anatomically feasible such as the pelvis. Further studies are required in order to better define the role of this technique as compared to intra-arterial chemotherapy or isolated limb perfusion.

Study design: In order to evaluate a new CECT (Continuous Enhanced Circulation Therapy) based on protocol for DVT prevention a prospective, randomize, single-blind study was designed to compare the effect of the new protocol to the current standard of care in DCT prophylaxis (LMWH).

Objectives: To evaluate and compare the incidence and severity of DVT between the two groups.

Background: Total hip and knee replacements are operations particularly prone to thromboembolic complications. Recommendations regarding prophylaxis have changed over the years. A treatment protocol was proposed, based upon the CECT system as the primary DVT prophylaxis method with the addition of low dose aspirin. This protocol is using two very safe treatment modalities with very low risk for adverse effects. The CECT system applies continuous mechanical enhancement of venous blood flow through a miniature, mobile, battery operated system.

Methods: 39 patients, who underwent total hip or knee replacement, were prospectively randomized into two groups. In the study group the patients received CECT system starting immediately after the induction of anesthesia and covering the operation and the first 5 postoperative days, within 12 hours after surgery aspirin 100 mg per day was added. In the control group the patients received Enoxaparin 40 mg per day for 5 postoperative days. A venography was performed at the 5th to 8th post-operative day and the DVT prevalence was compared.

Results: In the study group 3 patients out of 21 (14.3%) were found to have DVT (1 of them proximal), compared to 8 patients out of 18 (44.4%) in the control group (5 of them proximal). The differences between the two groups are statistically significant for both total and proximal DVT rates (p=0.037).

In the study group only 1 patient needed prolonged high dose anticoagulant treatment while 6 patients in the enoxaparin group were treated (p=0.020).

The cumulative incidence of adverse events in the study group was significantly lower than that observed in the control group (p=0.000). Average postoperative hospital stay was 8.4 days in the study group and 11.7 days in the control group (p=0.002).

The CECT device was very well tolerated by the patients and facilitated early mobilization.

Conclusions: The protocol combining CECT and Aspirin was found to be both safe the effective. Comparison to the standard prophylaxis with enoxaparin revealed significant advantage of the proposed protocol with: better DVT prevention, less adverse events and shorter hospital stay. Further research is needed in order to establish the place of this prophylaxis protocol as the treatment of choice in orthopaedic patients.

Vertebral fracture due to a metabolic bone disease or a neoplastic disease is a common and debilitating condition. It most often is associated with either osteoporosis or metastatic bone disease. Some of the patients suffering from such fractures continue to complain of back pain and deformity despite optimal medical therapy, including radiotherapy and biphosphonates.

Vertebroplasty, i.e. transcutaneous injection of bone cement into the vertebral body can serve as an internal fixation device and allows restoration of mechanical strength and partial restoration of the vertebral height.

During the year 2000, 17 vertebrae in 12 patients were injected. These were either lumbar or thoracic vertebrae. All patients reported decrease in pain and improved ambulation capacity.

Two minor complications were encountered including headache lasting for 72 hours prior to spontaneously resolving. This possibly indicates a transarachnoidal approach, the other complication has been cement leak below the posterior longitudinal ligament. The patient reported pain amelioration. No emergency surgical interventions were necessary to date.

Treatment of metastatic bone disease should be staged, with only a few vertebrae injected in each session, to prevent pulmonary embolization.

Vertebroplasty appears to allow excellent palliative treatment in patients suffering from unresectable primary tumors of the vertebrae, or more commonly, metastatic bone tumors as well as osteoporotic fractures.