Objective To assess the mid-term effectiveness of anterior decompression and fusion with nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage in treatment of cervical spondylotic myelopathy. Methods A retrospective study was made on 48 patients with cervical spondylotic myelopathy who underwent anterior decompression and fusion with n-HA/PA66 cage between August 2008 and January 2010. There were 33 males and 15 females with an average age of 54.5 years (range, 42-72 years). The disease duration was 3-12 months (mean, 6 months). The affected segments included 35 cases of single segment (C3, 4 in 7, C4, 5 in 18, and C5, 6 in 10) and 13 cases of double segments (C3-5 in 7 and C4-6 in 6). Of 48 patients, 28 was diagnosed as having intervertebral disc protrusion, 12 as having ossification of posterior longitudinal ligament, and 8 as having vertebral osteophyte; 35 patients underwent single segmental anterior corpectomy and fusion, and 13 patients underwent single segmental anterior discectomy and fusion. The pre- and post-operative radiographs (cervical anteroposterior and lateral X-ray films and three-dimensional CT scans) were taken to measure the segmental height and lordosis angle. Brantigan et al assessment standard and visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores were used to evaluate the graft fusion and the improvement of clinical symptoms, respectively. Results All patients were followed up for 46 months on average (range, 36-54 months). No cage breaking, displacement, or sliding was found. At last follow-up, 36 cases were rated as Brantigan grade E, 10 cases as grade D, and 2 cases as grade C; the fusion rate was 96%. Both segmental height and lordosis angle were corrected significantly at immediate and 6 months after operation and last follow-up than those before operation (P lt; 0.05), but no significant difference was found among different time points after operation (P gt; 0.05). At last follow-up, the cage subsidence was (1.3 ± 1.0) mm. The VAS and JOA scores at 6 months after operation and last follow-up were significantly improved when compared with preoperative scores (P lt; 0.05), and the scores at last follow-up were superior to ones at 6 months after operation (P lt; 0.05). Conclusion The mid-term effectiveness of anterior decompression and fusion with the n-HA/PA66 cage in patients with cervical spondylotic myelopathy is satisfactory because it can effectively restore and maintain segmental height and lordosis angle and promote osseous fusion.
Objective To investigate the surgical method and prel iminary cl inical result of managing the patient with lumbar burst fracture but not suitable for single-level fixation and fusion surgery with the reservation of the fractured vertebral body and the anterior decompression. Methods From September 2007 to December 2008, 11 patients with lumbar burst fracture underwent the removal of the posterior superior corner of the injured vertebral body, the removal of the inferior intervertebral disc adjacent to the injured vertebral body, bone graft fusion, and internal fixation. There were 8 males and3 females aged 21-48 years old (average 29.4 years old). All the fractures caused by fall ing from high places. Imaging exams confirmed all the fractures were Denis type B burst fracture. The fracture level was at the L1 in 4 cases, the L2 in 4 cases, the L3 in 2 cases, and the L4 in 1 case. Before operation, the nerve function was graded as grade B in 4 cases, grade C in 3 cases, and grade D in 4 cases according to Frankel scales; the visual analogue scale (VAS) was (7.30 ± 0.98) points; lateral X-ray films displayed the kyphosis Cobb angel was (24.94 ± 12.21)°; the adjacent superior and inferior intervertebral disc height was (12.78 ± 1.52) mm and (11.68 ± 1.04) mm, respectively; CT scan showed the vertebral canal sagittal diameter was (9.56 ± 2.27) mm; CT three-dimensional reconstruction revealed that the intact part of the injured vertebra was less than 50% vertebra body height and the fracture l ine crossed the pedicle. The time from injury to operation was 3-11 days (average 4.8 days). The neurological and radiological evaluations were carried out immediately and 3 months after operation, respectively, and compared with the condition before operation. Results All the patients successfully underwent the surgery. The wound all healed by first intention. All the patients were followed up for 6-18 months (average 14 months). All the patients had a certain degree of nerve function recovery. The Frankel scales in all the patients were increased by 1-2 grade immediately and 3 months after operation. The VAS score was (2.80 ± 1.49) points immediately after operation and (1.54 ± 0.48) points 3 months after operation, suggesting there were significant differences among three time points (P lt; 0.05). The vertebral canal sagittal diameter was significantly enlarged to (18.98 ± 4.82) mm immediately after operation and was (19.07 ± 4.37) mm 3 months after operation. The Cobb angle was (7.78 ± 4.52)° immediately after operation and (8.23 ± 3.57)° 3 months after operation. There were significant differences between before and after operation (P lt; 0.05). For the adjacent superior and inferior intervertebral disc height, there was no significant difference when the value immediately or 3 months after operation was compared with that of before operation (P gt; 0.05). X-ray films and CT scan 3 months after operation showed good internal fixation without theoccurrence of loosing and displacement. Conclusion For the treatment of lumbar burst fracture, the method of reserving the injured vertebral body and anterior decompression can decompress the vertebral canal and shorten the duration for bony fusion.
To compare and evaluate the whole effect of anterior decompression approach to treat cervical spondylotic myelopathy by using cervical retractor systems and the traditional surgical approach. Methods From April 2001 to August 2004, group A included 30 males and 23 females aging from 31 to 69 years, and the involved time was from 7 months to 15 years. Involved segments included 22 one-segments, 24 two-segments and 7 three-segments. In all 53 cases, anterior windowing decompression and fusion with autograft and titanium plate internal fixation by using traditionalcircular saw were performed. Group B included 48 males and 20 females aging from 33 to 74 years, and the involved time was from 5 months to 18 years. Involved segments included 23 one-segments, 34 two-segments and 11 three-segments. In all 68 cases, anterior undermined far-reaching decompression and fusion with autograft and titanium plate internal fixation by using removing disc merely in the single-level or separately in the multilevels employing self-retractor and Caspar cervical retractor systems via interspinal approach were performed. X-rays and MRI showed cervical disc degeneration, herniation and spinal cord compression. The surgery time, loss of blood, vertebral body fusion time, difference in height of involved segments preor postoperatively and compl ications were counted up and compared between the two groups. Improvement rate of spinal function pre- or postoperatively were valued by using JOA score. Results A total of 92 cases including 42 of group A and 50 of group B were followed up for 3 to 5 years, mean 3.5 years. In group A, surgery time, loss of blood, time of vertebral body fusion, difference in height of involved segments pre- or postoperatively, and improvement ratio of spinal function were(76.80 ± 28.41) min,(564.00 ± 181.96) mL,(12.10 ± 3.58) weeks, (1.30 ± 0.67) mm and 0.49% ± 0.14%, respectively. In group B, they were(57.90 ± 15.01) min,(317.50 ± 136.92) mL,(9.75 ± 1.36) weeks, (3.00 ± 0.56) mm and 0.71% ± 0.17% , respectively. The differences between the two groups were significant in all measured values(P lt; 0.05). Compl ications occurred in 7 cases ofgroup A including 1 spinal cord injury, 1 plate displacement, 1 bonegraft displacement and 4 disfunctions of il iac region. No compl ication happened in group B. Conclusion Anterior decompression approach using cervical retractor systems is significantly superior to the traditional approach as to the whole effect to treat cervical spondylotic myelopathy, and furtherperfects the traditional anterior decompression approach. The modified approach is scientific, safe and easily spread.
Objective To explore the injury mechanism of the severethoracolumbar burst fracture and the necessity of anterior decompression and reconstruction with internal fixation. Methods From January 1999 to January 2004, 21 patients were treated with anterior decompression and reconstruction. The fractures were located at T12 in 6 patients, L1 in12, L2 in 4, L3 in 3,and L4 in 1. Four patients were treated with the “anterior approach” and “posterior approach” surgeries for severe column fractures.Results All the patients were restored to the normal physiological radian, and the spinal canal was decompressed completely. They werefollowed up for 1-6 years, and the bony fusion was observed radiologically.The spinal cord function was improved to the 1-3 Frankel grade in all the patients except 2. There were no such complications as leakage of the cerebrospinal fluid, platescrew loosening or breaking, or segment instability. The clinical effects were satisfactory. Conclusion The operation of the anterior decompression and reconstruction with internal fixation for severe thoracolumbar burst fracture has advantages of complete decompression, full bonegrafting, and firm internal fixation. It canrestore the spinal height and improve the spinal cord function.