Does the Relationship Between Bone Cement and the Intravertebral Cleft of Kummell Disease Affect the Efficacy of PKP?

OBJECTIVE: To study the relationship between distribution of bone cement and intravertebral cleft of patients with Kummell disease on the clinical effect of percutaneous kyphoplasty (PKP). METHODS: According to the relationship between the distribution of bone cement and the cleft in the vertebrae, a total of 92 patients with Kummell disease who underwent PKP in our hospital were divided into 2 groups. Specifically, the bone cement of patients in group A was localized in the cleft of the vertebrae and did not infiltrate around the cleft, while that of group B patients not only filled the cleft of the vertebrae, but also distributed diffusely around the cleft of the vertebrae. The amount of bone cement injected, leakage rate, visual analogue scale (VAS) score, Oswestry Disability Index (ODI), and vertebral imaging changes before operation, and 2 days and 1 year after operation were compared between the 2 groups. RESULTS: The amount of bone cement injected and the permeability of bone cement in group B were higher than those in group A (P < 0.05). The scores of VAS and ODI in both groups were significantly improved after operation, but the two scores in group B were better than those in group A one year after operation. The height of anterior vertebral body and Cobb's angle of kyphosis in the 2 groups were significantly improved after operation, but 1 year after operation, those in group B were better than those in group A. CONCLUSIONS: PKP was an effective method for treating Kummell disease. At the same time, the relationship between the distribution of bone cement and the cleft in the vertebral body was an important factor affecting the curative effect after PKP. The effect of the distribution pattern of bone cement filled with intravertebral cleft and diffusely distributed around the fissures was better than that of bone cement confined in the vertebral cleft.

Occipitocervical Fusion via Cervical Pedicle Fixation Assisted with O-arm Navigation.

OBJECTIVE: To describe the clinical outcomes of occipitocervical fusion (OCF) using cervical pedicle fixation with assistance of O-arm navigation and present its clinical feasibility. METHODS: From January 2015 to December 2016, eight patients with a variety of diagnoses were surgically treated with occipitocervical fusion using cervical pedicle screws under O-arm navigation. All patients received full workup consisting of clinical and radiological assessments. Perioperative parameters including operating time, intraoperative blood loss, postoperative complications, surgical outcomes were recorded. Postoperative data were acquired resorting to the scheduled follow-up 3, 6 and 12 months after their discharge and annually afterwards. The Japanese Orthopaedic Association (JOA) Scores and American Spinal Injury Association (ASIA) Scale were used to evaluate neurological function. The accuracy of screw placement was classified according to a modified classification of Gertzbein and Robbins. The fusion status was evaluated in reference to the Bridwell's posterior fusion grades. RESULTS: The patient cohort comprised of five males and three females, with the average age of 51.9 years (range from 18 to 74 years). The patients all showed indications for OCF and were performed with polyaxial screws through cervical pedicles. The average operation time was 274 min (range from 226 to 380 min), with the intraoperative blood loss of 437.5 mL and the blood transfusion volume of 481.3 mL. The average follow-up time was 23.5 months (range from 17 to 32 months). All patients exhibited radiographic evidence of osseous fusion by X-ray and computed tomography (CT) at the final follow-up. No neurovascular complications were found during the follow-up time, and the clinical symptoms were observed to be significantly improved in all the patients. Thirty-four cervical pedicle screws were implanted within the eight patients, with the accuracy of cervical pedicle screw placements as 94.1% (32/34), among which, two pedicle screws were found to broken through the cervical pedicles that were evaluated as Grade II. CONCLUSIONS: Occipitocervical fusion via cervical pedicle fixation assisted with O-arm navigation is a feasible and safe procedure with a vast range of indications.

Minimally Invasive Pedicle Screw Fixation Combined with Percutaneous Kyphoplasty Under O-Arm Navigation for the Treatment of Metastatic Spinal Tumors with Posterior Wall Destruction.

OBJECTIVE: To evaluate the safety and efficacy of O-arm-guided minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for metastatic spinal tumors with posterior wall destruction. METHODS: Patients who underwent minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for pathological vertebral fractures with posterior wall defects from January 2015 to December 2017 were followed up for 1 year. Visual analogue scale (VAS), SF-36 scores, middle vertebral height, posterior vertebral height, and the accuracy of pedicle screws were assessed preoperatively, postoperatively, and 1 year after surgery. The operation time, time from operation to discharge, blood loss, volume of bone cement, and leakage of bone cement were recorded. RESULTS: Twenty-three patients (13 females and 10 males) who met our criteria were followed up for 1 year. The operation time of these patients was 162.61 ± 33.47 min, the amount of bleeding was 230.87 ± 93.76 mL, the time from operation to discharge was 4.35 ± 2.42 days, and the volume of bone cement was 3.67 ± 0.63 mL. The VAS score decreased from 7.04 ± 1.07 to 2.65 ± 0.93 before surgery (P = 0.000) and remained at 2.57 ± 0.79 1 year after surgery. Compared with the preoperative SF-36 scores for physical pain, physiological function, energy, and social function, the postoperative scores were significantly improved (P = 0.000). The height of the middle vertebral body increased from 14.47 ± 2.96 mm before surgery to 20.18 ± 2.94 mm (P = 0.000), and remained at 20.44 to 3.01 mm 1 year after surgery. The height of the posterior vertebral body increased from 16.56 ± 3.07 mm before operation to 22.79 ± 4.00 mm (P = 0.000), and 22.45 ± 3.88 mm 1 year after surgery. The 23 patients had a total of 92 pedicle screws; 85 screws were Grade A and 7 screws were Grade B. There was no leakage of bone cement after surgery. CONCLUSION: In the short term, O-arm-guided minimally invasive pedicle screw fixation combined with kyphoplasty is safe and effective in the treatment of metastatic spinal tumors with posterior wall destruction.