Comparison of electromagnetic and optical navigation assisted Endo-TLIF in the treatment of lumbar spondylolisthesis.

Uniportal full endoscopic posterolateral transforaminal lumbar interbody fusion (Endo-TLIF) with percutaneous pedicle screw fixation is a promising, minimally invasive method for the treatment of lumbar spondylolisthesis. However, repeated radiation exposure from X-rays and the steep learning curve remain to be improved.

[Construction and biological assessment of tissue engineering intervertebral disc].

OBJECTIVE: To investigate the value of bone marrow-mesenchymal stem cells (BM-MSCs) transformed by nucleus pulposus (NPs) for construction of tissue engineering disc. METHODS: BM-MSCs and fetal NPs were cultured in vitro, planted on polylactic acid-polyglycolic acid copolymer (PLGA), and observed with inverted microscope and scanning electronic microscope. PLGA scaffolds with adherent BM-MSCs and NPs, as well as BM-MSCs and NPs suspension were implanted into intervertebral discs of New Zealand white rabbits, respectively. Intervertebral signal intensity was evaluated by Thompson grading 12 weeks later. Proteoglycan and type IIcollagen were determined by spectrophotometric method and immunohistochemistry, respectively. RESULTS: Spindle or multi-angular BM-MSCs turned into fibro-like phenotype coculture of BM-MSCs and NPs, which grew well with normal morphology when they attached on PLGA scaffolds. There was statistical difference in intervertebral signal intensity, and the expression of proteoglycan and type IIcollagen between PLGA scaffolds group and control group (P < 0.05), the content of proteoglycan was (3.93 ± 0.31) mg/100 mg in the PLGA scaffolds group whereas (3.52 ± 0.26) mg/100 mg in the control group. CONCLUSIONS: BM-MSCs can be induced into NPs by cocultivation, and PLGA scaffolds can provide good growing conditions, and maintain high mechanical properties and spacial structure which meet the requirement of tissue engineering disc to prevent degeneration.

Accuracy and deviation analysis of robot-assisted spinal implants: A retrospective overview of 105 cases and preliminary comparison to open freehand surgery in lumbar spondylolisthesis.

BACKGROUND: Whether the accuracy of robot-assisted spinal screw placement is significantly higher than that of freehand and the source of robotic deviation remain unclear. METHODS: Clinical data of 105 patients who underwent robot-assisted spinal surgery was collected, and screw accuracy was evaluated by computed tomography according to the modified Gertzbein-Robbins classification. Patients were grouped by percutaneous and open surgery. Intergroup comparisons of clinical and screw accuracy parameters were performed. Reasons for deviation were determined. Thirty-one patients with lumbar spondylolisthesis undergoing open robot-assisted surgery and the same number of patients treated by open freehand surgery were compared for screw accuracy. RESULTS: Screw accuracy was not significantly different between the percutaneous and open groups in both intra- and postoperative evaluations. Tool skiving was identified as the main cause of deviation. The proportion of malpositioned screws (grade B + C + D) was significantly higher in the freehand group than in the robot-assisted group. However, remarkably malpositioned (grade C + D) screws showed no significant differences between the groups. No revision surgery was necessary. CONCLUSIONS: Robot-assisted spinal instrumentation manifests high accuracy and low incidence of nerve injury. Tool skiving is a major cause of implant deviation.

Massively prolapsed intervertebral disc herniation with interlaminar endoscopic spine system Delta endoscope: A case series.

BACKGROUND: Surgery is often indicated for patients with massively prolapsed intervertebral disc herniation. The interlaminar endoscopic spine system (iLESSYS) Delta 6-mm working channel endoscope has advantages over other systems. The aim of this study was to explore the benefits and complications of using the iLESSYS Delta for the treatment of massively prolapsed intervertebral disc herniation. AIM: To explore the clinical benefits of treating massively prolapsed lumbar intervertebral disc herniation with the iLESSYS Delta endoscope. METHODS: In this study, the data of 37 patients who underwent surgery with the iLESSYS Delta endoscope at The Affiliated Hospital of Qingdao University were retrospectively analyzed. Intraoperative blood loss, operation time, and complications were collected. The visual analog scale (VAS), oswestry disability index (ODI), and modified MacNab criteria were determined before and at 1 d, 3 mo, and 6 mo after surgery. RESULTS: The mean intraoperative blood loss was 20.4 ± 1.2 mL. The mean operation time was 97.3 ± 12.4 min. The VAS scores for leg and back pain decreased from 68.0 ± 7.3, 34.4 ± 8.5 before operation to 2.5 ± 1.7, 5.5 ± 1.9 at 6 mo after surgery, respectively. The ODI also decreased from 60.2 ± 7.3 to 17.9 ± 3.4 at 6 mo after surgery. The improvement rate of the MacNab score was 86.4%, which was considered excellent. No spinal dural injury, nerve root injury, secondary protrusion of intervertebral disc, or myeloid hypertension was found during follow-up. CONCLUSION: The iLESSYS Delta 6-mm working channel endoscope has several advantages in terms of clinical and functional benefits, complications, and low risk of residual vertebral pulp in treating patients with massively prolapsed intervertebral disc herniation.

[Diagnosis and treatment of disc herniation at cervical vertebra 7-thoracic vertebra 1 (C(7)-T(1))].

OBJECTIVE: To study the outcome of laminoforaminotomy with posterolateral discectomy for patients with lateral disc herniation at C(7)-T(1). METHODS: From August 2000 to August 2008, 12 patients with lateral disc herniation at C(7)-T(1) underwent posterolateral discectomy were analyzed retrospectively. Neurologic function were evaluated with the Motor Scoring System. Preoperative motor were compared with postoperative one. The unique clinical manifestation, imageology features and intraoperative findings were analyzed. RESULTS: All these twelve patients were lateral type. All the patients showed hand intrinsic muscles atrophy and hand weakness. Nine patients had no paraesthesia. The average follow-up period was 26 months. Postoperative scores were significantly higher than preoperative ones. CONCLUSIONS: Disc herniation at C(7)-T(1) is predominantly lateral type and present C(8) nerve motor deficit (hand intrinsic muscles atrophy and hand weakness) and only minority has paraesthesia in C(8) nerve dermatome. Posterolateral cervical discectomy technique is safe and effective for patients with lateral disc herniation at C(7)-T(1).

Lentivirus-mediated TGF-ß3, CTGF and TIMP1 gene transduction as a gene therapy for intervertebral disc degeneration in an in vivo rabbit model.

The present study examined the effects of transforming growth factor (TGF)-ß3, connective tissue growth factor (CTGF) and tissue inhibitor of metalloproteinase 1 (TIMP1) gene transduction, using a lentiviral vector, on rabbit intervertebral disc degeneration in vivo, with the intention of investigating their potential use in gene therapy. A model of lumbar intervertebral disc degeneration was created by needle puncture into the annulus fibrosus of 15 New Zealand white rabbits. Empty lentivirus or recombinant lentiviral plasmid lenti-TGFß3-P2A-CTGF-T2A-TIMP1 was injected into degenerative lumbar intervertebral discs (representing the control and experimental groups, respectively), whilst untreated degenerative lumbar intervertebral discs served as the puncture group. After 16 and 20 weeks, magnetic resonance imaging (MRI) was conducted and the changes in intensity on micrographs of degenerative intervertebral discs were measured. The mRNA levels of aggrecan and type II collagen in nucleus pulposus tissue were determined by reverse transcription-polymerase chain reaction, and protein expression levels of type II collagen and aggrecan were determined by western blot analysis. MRI results indicated that intervertebral disc degeneration was ameliorated in the experimental group when compared with the control and the puncture group. Furthermore, the expression levels of type II collagen and aggrecan in the puncture and control groups were significantly lower than in the experimental group (P<0.05). In conclusion, lenti-TGFß3-P2A-CTGF-T2A-TIMP1 co-transduction can promote synthesis of aggrecan and type II collagen in degenerative intervertebral discs, thereby delaying intervertebral disc degeneration. These results indicate the potential of gene therapy in treatment of intervertebral disc degeneration.

One stage laminoplasty and posterior herniotomy for the treatment of myelopathy caused by cervical stenosis with cervical disc herniation.

The aim of the study was to introduce a method of one stage laminoplasty and posterior herniotomy for myelopathy caused by cervical stenosis with cervical disc herniation and to evaluate the clinical efficacy of this surgery. From 1999 to 2008, 18 patients with myelopathy caused by cervical stenosis with cervical disc herniation who underwent this procedure were included. The average age was 63 years (range 48-74 years), and the average follow-up period was 46 months (range 3-108 months). Neurologic status was evaluated using the JOA scoring system. Neurological symptoms improvement was seen in all patients after surgery. The average JOA score was 14.22±1.86 by final follow-up, which was higher than preoperative values (P<0.01), and the average improvement in neurological function was 76.63%. Neurologic examination showed that excellent results had been obtained by 10 patients, good results by 8 patients, with no fair or poor results. 2 patients developed cerebrospinal fluid leakage after surgery and recovered during the follow-up period. One patient with cervical disc herniation developed postoperative C5 palsy on the axle side on the third day after surgery. She completely recovered by 1 month after surgery. No other patients experienced postoperative neurologic complications. Complete anterior and posterior decompression of the spinal cord was achieved after surgery. We concluded that one stage laminoplasty and posterior herniotomy is an effective, reliable, and safe procedure for the treatment of myelopathy caused by cervical stenosis with cervical disc herniation.