Percutaneous Cementoplasty for the Pelvis in Bone Metastasis: 12-Year Experience.

BACKGROUND: In advanced cancer patients, pelvic bone metastasis often causes pain and gait disturbance. The use of percutaneous bone cement [polymethylmethacrylate (PMMA)] injection for pain management and strengthening in pelvic bone metastasis has rarely been reported. To evaluate this method, we aimed to determine surgical outcomes and complications over a long-term follow-up period using a large patient group. PATIENTS AND METHODS: We retrospectively collected data from 178 patients who underwent percutaneous cementoplasty for pelvic metastatic lesions, 201 in total. Surgical outcomes evaluated included pain reduction and improvement of ambulation. Mortality within 1 month after procedure and pulmonary embolism caused by thrombus, fat, tumor emboli, or bone cement were investigated as surgical complications. For long-term survivors, pain relapse and mechanical failure were analyzed. The mean follow-up period was 12.6 months, and there were 159 fatalities at last follow-up. RESULTS: The mean regional pain numerical rating scale scores decreased from 6.1 preoperatively to 2.4 1 month after procedure (p < 0.01). Gait function was maintained, worsened, and uncheckable in 68%, 24%, and 8% of patients, respectively, 1 month after procedure. Of long-term survivors followed up for > 12 months (n = 53), there were no significant changes in serial plain radiographs, and regional pain aggravation was observed in 9%. Pulmonary cement embolism and bone cement implantation syndrome was observed in 11% and 10%, respectively. However, all patients with these complications were asymptomatic. CONCLUSIONS: Percutaneous cement injection into the pelvis is a feasible and safe palliative surgical option for patients with advanced malignancy in terms of pain reduction and maintenance of ambulatory function under regional anesthesia.

Preliminary results: use of multi-hole injection nails for intramedullary nailing with simultaneous bone cement injection in long-bone metastasis.

OBJECTIVE: For symptomatic metastasis of the long bones, intramedullary nailing has been the most accepted fixation method. Intramedullary nailing has effective control of pain, perioperative bleeding, and local tumor progression by augmentation with bone cement around the nail. Here, we report the preliminary results of a new surgical implant that allows for simultaneous injection of bone cement while inserting a percutaneous, flexible intramedullary nail. MATERIALS AND METHODS: We performed palliative surgeries for long-bone metastasis using a multi-hole injection nail (MIN) with multiple side holes in the distal one third. When the nail tip entered the metastatic cancer lesion, the bone cement injection was started, and continued until the nail was completely seated. Ten patients with advanced cancer underwent palliative surgery using the new implant with simultaneous bone cement injection for humeral (n = 4), femoral (n = 4), and tibial (n = 2) metastases. RESULTS: The mean operative time was 42 min (range, 36-52 min). The mean length of the injection nail was 23.0 cm (range, 18.0-33.0 cm), and the mean volume of cement was 28.0 ml (range, 14.0-40.0 ml). Marked pain palliation (p < 0.001) and functional recovery (p = 0.01) were verified. The mean Musculoskeletal Tumor Society (MSTS) functional score improved significantly from 12.5 at 6 weeks preoperatively, to 24.9 postoperatively. No acute postoperative complications, including cement embolism, occurred. CONCLUSION: This minimally invasive surgical method with MIN could be useful for stabilization of long-bone metastases in patients with advanced cancer.

Joint-preserving palliative surgery using self-locking screws of intramedullary nail and percutaneous cementoplasty for proximal humeral metastasis in the advanced cancer patients.

BACKGROUND: We introduced a palliative joint-preserving surgery using proximal self-locking screws of intramedullary (IM) nail and percutaneous cementoplasty (PC) in patients with proximal humeral metastases, including the head and neck, and evaluated the outcome of the surgical method. METHODS: Twenty-three patients (mean age = 63.0 ± 11.8 years, M:F = 14:9) had IM nailing with a self-locking screw system and PC for the treatment of humeral head and neck metastases. Usually, three proximal locking screws were inserted after IM nailing, and 20.9 ± 8.0 ml of polymethylmethacrylate (PMMA) bone cement was injected in the perimetal osteolytic area. RESULTS: Regional anesthesia with interscalene block was performed in 87.0% (20/23), and the duration of surgery (from anesthesia to awakening) was approximately 40-55 min. Red blood cell was not transfused intra- and/or postoperatively in 65.2% (15/23). The localized preoperative pain (visual analog scale (VAS), 8.2 ± 3.1) was gradually decreased at postoperative 1 week (VAS, 4.9 ± 2.1) and at 6 weeks (VAS, 2.9 ± 2.1) (P < 0.001). Among nine patients who underwent F-18-FDG PET/CT, the proximal humeral metastasis around PC showed improved, stable, and aggravated states in five (55.6%), three (33.3%), and one patient (11.1%), respectively. Meanwhile, 88.8% (8/9) of patients showed aggravation at the naive bone metastasis area. CONCLUSION: The selection of the self-locking screw type of the IM nail and PC was helpful in preventing fixation failure for joint-preserving palliative surgery in the proximal humeral metastasis.

Percutaneous Cementoplasty For Acetabulum In Patients With Bone Metastasis.

The purpose of this study is to demonstrate the surgical technique and to show the results of percutaneous cementoplasty (PC) for acetabular metastases using lateral approach under regional anesthesia. Forty-two cases underwent PC for acetabular metastases. The PC was performed using spinal anesthesia, lateral approach and fluoroscopic guidance. We assessed visual analogue scale (VAS) and revised musculoskeletal tumor society (MSTS) rating system and maximum standardized uptake value (SUVmax) of the acetabular lesion using F-18-FDG PET/CT before and after the PC. The mean injected volume of polymethylmethacrylamide to the pelvis was 21±11.8 ml. The mean of regional VAS (6.2±1.1 vs. 3.1±2.7, p<0.001), MSTS (10.3±3.9 vs. 18.3±3.2, p<0.001) and local SUVmax (8.6±5.2 vs. 5.7±3.6 , p = 0.012) on PET/CT showed significant reductions after surgery. Twenty-three patients (55%) died of disease at mean 11.8±4.8 months after surgery. PC using lateral approach and regional anesthesia could be a simple and safe surgical method for relieving pain and maintaining skeletal stability against acetabular metastasis.

Whole Blood Titanium Concentration after Limb Salvage Surgery with Three-Dimensional-Printed Ti6Al4V Implants.

Background: Three-dimensional (3D)-printed customized implants can be fabricated and utilized for all bones with massive bone defects. The main safety issues with 3D-printed implants made of Ti6Al4V alloy are related to the release of metal debris and residual powder. In this study, we investigated the perioperative titanium concentrations in whole blood and peri-implant fluid samples of patients who underwent limb salvage surgery with a 3D-printed Ti6Al4V implant. Methods: Nineteen patients who underwent limb salvage surgery with 3D-printed Ti6Al4V implants were divided into two groups: the serial samples group and the follow-up group. To observe metal distribution and clearance in the body, serial samples of blood and peri-implant fluid from the surgical drain were prospectively collected for five patients in the serial samples group. For the remaining 14 patients who were followed up for more than a year, blood samples were collected only once. Results: In the serial samples group, the mean baseline titanium concentration was 0.78 µg/L (range, 0.1-2.2 µg/L): 3 patients showed peak concentration before the third postoperative month, while 2 patients still showed an increasing pattern at this point. Total titanium mass in the surgical drain showed a wash-out phenomenon in a week, with a significant uniform decrease (p = 0.04). In 14 patients in the follow-up group, the mean titanium concentration in the whole blood was 10.8 µg/L (range, 0.3-36.6 µg/L). For the 14 patients with a long-term follow-up, the aluminum and vanadium concentrations were all negligible. Conclusions: Whole blood titanium concentrations were higher after surgery using 3D-printed implants than after that using conventional orthopedic implants, but markedly lower than in patients with implant failure. None of the patients developed serious clinical adverse effects during follow-up.

Evaluation of Intraosseous Pressure during Pelvic Percutaneous Cement Injection: An In Vitro Study in Swine.

Background: A minimally invasive procedure for symptomatic pelvic bone metastasis is a feasible option for advanced cancer patients, and bone cement injection plays an essential role. Pulmonary embolism caused by thrombus, fat, or tumor emboli is a major complication related to bone cement injection, and increasing intraosseous pressure is a predisposing factor. This study aimed to quantify the degree of pressure change in the pelvic bone during percutaneous bone cement injection and investigate whether there is a significant decrease in intraosseous pressure when a decompressive route is additionally established. Methods: Bone cement injection into the acetabulum of swine pelvises by simulating the actual surgical procedure in terms of the injection method, bone cement, and surgical instruments was performed while recording the intraosseous pressure. Twenty swine pelvises were used and grouped into a decompression group and a non-decompression group. Bone cement injection and pressure measurement were conducted in the same way in both groups, but an additional decompressive route was established for each pelvis in the decompression group. Continuous variables were compared using the Mann-Whitney test. Results: The mean amount of injected bone cement was 19.8 mL and 20.3 mL and the mean speed of bone cement injection was 0.14 mL/sec and 0.12 mL/sec in the decompression group and the non-decompression group, respectively. The mean peak intraosseous pressures was 10.5 kPa with decompression and 37.8 kPa without decompression, and the difference was statistically significant (p < 0.01). Conclusions: Intraosseous pressure during bone cement injection into swine pelvises was similar to that during vertebroplasty or kyphoplasty. When the additional decompression route was established, the intraosseous pressure decreased to one third the level.

MRI-guided navigation surgery with temporary implantable bone markers in limb salvage for sarcoma.

BACKGROUND: Technical errors during navigation-assisted bone tumor resection may occur by: (1) incorrect registration of images and corresponding anatomic points of bone sent to the navigation system; and (2) incorrect fusion of two or more images that have been transported to the navigation system. QUESTIONS/PURPOSES: We investigated new methods of navigation surgery to minimize technical errors during the registration and image fusion processes and specifically asked whether a navigated cannula probe would reduce unnecessary soft tissue dissection, and allow percutaneous registration and implantation of a reference base tracker in the margin of bone to be resected. METHODS: We performed direct MRI-guided navigation surgery without image fusion on a patient with osteosarcoma using absorbable pins as temporary implanted bone markers that prevent artifacts on MR images. RESULTS: Direct MRI-guided navigation surgery was possible using bone markers. A navigated cannula probe allowed percutaneous registration and a navigated blade-shaped probe provided a real-time check on the narrow osteotomy gap. The surgical procedure was facilitated by implantation of a reference base tracker on the margin of bone to be resected. CONCLUSIONS: Our modified technique of MRI-guided navigation surgery for patients with a malignant bone tumor may reduce processing errors by increased accuracy and be helpful for joint preserving surgery.

Minimally invasive surgery for femoral neck fractures using bone cement infusible hollow-perforated screw in high-risk patients with advanced cancer.

OBJECTIVE: Pathologic or osteoporotic femoral neck fractures usually treated with joint replacement surgery rather than joint-preserving surgery because multiple screw fixation has a high risk for fixation failure and nonunion as well as the need for a postoperative protection period. However, joint-preserving surgery might be preferable in high-risk patients with short life expectancy due to advanced disease. Recently introduced hollow-perforated screws are devices for achieving percutaneous fixation by simultaneous injection to the weak bone area through its multiple side holes. We report our experience of surgical treatment of femoral neck fractures by controlled bone cement injection into the femoral head and neck through a modified hollow-perforated screw in patients with advanced cancer. METHODS: We modified the hollow perforated screw with variable placing of screw-side holes as fracture patterns. Polymethylmethacrylate (PMMA) bone cement was injected through the screw holes to control its injection into the selective areas of the femoral head and neck while avoiding the fracture sites. One or two of these were fixed percutaneously in 12 patients who have Garden stage I or II femoral neck fractures in the advanced state of advanced cancer. Seven patients had pathologic fracture by metastatic cancer, but 5 had osteoporotic fractures. RESULTS: Eleven patients died a mean of 4.1 months after surgery and 1 patient lived with ability to walk for 48 months. Sixteen modified hollow perforated-screws and 16 standard cannulated screws were used for fixation. The mean volume of cement injection was 13.8 ml. The complication developed in 4 patients: cement leakage to the hip joint in 2 patients, subtrochanteric fracture in 1 patient (5 months after surgery) and fixation failure in 1 patients (2 months after surgery). Nine patients could walk with or without a walking aid, and all others also could return to the prefracture-ambulation state with effective pain relief on the third postoperative day. CONCLUSION: This current surgical method could be useful in patients with short life expectancy because of quick pain relief, early return to ambulation, simple operative procedures and short hospital stay. The modified hollow perforated screw which has a diversity of side hole locations for the regulation of bone cement injection into the planned area seems useful for selective femoral neck fractures.

Palliative percutaneous stabilization of lower extremity for bone metastasis using flexible nails and bone cement.

OBJECTIVE: Percutaneous stabilization (PS; percutaneous flexible nailing and intramedullary bone cement injection) was performed at lower extremity long bones in patients with multiple bone metastases with short life expectancy to get mechanical stability and local tumor control. We evaluated the usefulness of PS by clinical status, F-18-FDG PET-CT and bone scintigraphy (BS). METHODS: Patients comprised 15 patients (total 20 sites) who had undergone PS for the metastatic bone tumors of lower extremity long bones (femur and tibia). After percutaneous flexible nailing, bone cement was injected (mean amount=15.5±6.4 ml). Patients' clinical status was evaluated by visual analog scale (VAS). Qualitative assessment of PET-CT and BS was categorized by improved, stable and aggravated states of PS lesion. Quantitative assessment of PET-CT was performed by maximum and mean standardized uptake value (SUVmax and SUVmean). RESULTS: PS was performed in all of the patients without complication, and showed significant pain improvement of VAS (7.2±0.2 vs. 2.8±0.3, P<0.001). PS lesion showed improved state in 65% (13/20) and stable state in 35% (7/20). However, naive bony metastatic lesion showed mostly aggravated state in 90% (19/20) in the same patients, which was significantly different compared with PS lesion (P<0.001). In PS lesion, SUVmax (10.1±6.9 vs. 7.1±5.2, P=0.008) and SUVmean (6.2±4.8 vs. 4.6±3.7, P=0.008) showed significantly decreased uptake after PS. CONCLUSION: By PS in lower extremity long bones, patients can reduce regional pain, and has the possibility of local tumor control. PS can be performed for lower extremity bone metastasis in poor general condition to perform conventional intramedullary nailing.

Minimally invasive surgery of humeral metastasis using flexible nails and cement in high-risk patients with advanced cancer.

This study was conducted to evaluate the preliminary outcome of palliative minimally invasive surgery for humeral metastasis in patients who have multiple advanced cancers with short life expectancy. Percutaneous Ender nailing and direct transcortical intramedullary cementing were performed on a total of 15 patients with metastatic disease of the humerus. The origins of the cancers were the lung (n=9), breast (n=3), colon (n=2) and liver (n=1). Each patient had multiple unresectable organic metastases and proved to be at high risk for anesthesia and bloody surgery. All procedures were performed under regional anesthesia and fluoroscopic guidance. The mean amount of intramedullary cement injection after Ender nailing was 13.4ml. The mean of the numeric rating scale (NRS) score for pain decreased from 9.6 points before surgery to 3.6 points after surgery (P<0.001). The mean of the Musculoskeletal Tumor Society (MSTS) functional score increased from 10.6 points before surgery to 19.9 points after surgery (P<0.001). Seven patients died within 7 months. There were no complications associated with cement leakage, fixation failure and surgical wound even in cases of early postoperative radiation or chemotherapy. Percutaneous flexible nailing along with intramedullary cementing could be a useful minimally invasive surgical method for the palliation of humeral metastasis in selective terminal cancer patients by providing immediate reliable fixation and effective pain relief.

Grafting using injectable calcium sulfate in bone tumor surgery: comparison with demineralized bone matrix-based grafting.

BACKGROUND: Injectable calcium sulfate is a clinically proven osteoconductive biomaterial, and it is an injectable, resorbable and semi-structural bone graft material. The purpose of this study was to validate the clinical outcomes of injectable calcium sulfate (ICS) grafts as compared with those of a demineralized bone matrix (DBM)-based graft for filling in contained bony defects created by tumor surgery. METHODS: Fifty-six patients (41 males and 15 females) with various bone tumors and who were surgically treated between September 2003 and October 2007 were included for this study. The patients were randomly allocated into two groups, and either an ICS graft (28 patients) or a DBM-based graft (28 patients) was implanted into each contained defect that was developed by the surgery. The radiographic outcomes were compared between the two groups and various clinical factors were included for the statistical analysis. RESULTS: When one case with early postoperative pathologic fracture in the DBM group was excluded, the overall success rates of the ICS and DBM grafting were 85.7% (24/28) and 88.9% (24/27) (p > 0.05), respectively. The average time to complete healing was 17.3 weeks in the ICS group and 14.9 weeks in the DBM group (p > 0.05). Additionally, the ICS was completely resorbed within 3 months, except for one case. CONCLUSIONS: Although the rate of resorption of ICS is a concern, the injectable calcium sulfate appears to be a comparable bone graft substitute for a DBM-based graft, with a lower cost, for the treatment of the bone defects created during surgery for various bone tumors.