Objective To investigate the operational method of cervical vertebral flavectomy and its cl inical appl ication in the management of cervical canal stenosis. Methods From June 1997 to June 2007, 25 patients suffering from cervical spinal canal stenosis caused by obvious flaval l igament hypertrophy were given flavectomy. There were 22 males and 3 females, with an age range of 32 to 68 years (average 54 years). The course of disease was from 3 weeks to 7 years, with an average of 3 years and 7 months. All patients had degenerative cervical canal stenosis; of them, 5 cases had a history of cervical injury 2 to 3 weeks before operation (3 cases of fall ing injury and 2 cases of traffic accident injury). The X-ray film, CT, and MRI examinations showed that the compression locations were C4-7 in 12 cases, C3-7 in 9 cases, C5-7 in 3 cases, and C6,7 in 1 case. Spinous process and vertebral lamella were exposed by central posterior approach. The insertions of flaval l igaments were cut off at the superior vertebral lamella border, then the starting points of which were cut down from the anterior side of the upper vertebral lamella at their inferior border after l ifting up the flaval l igaments. The residual flaval l igaments in front of the vertebral lamella were scraped off by slope rongeur, the dura mater then could be seen to inflate from the intervertebral lamella space, showing the compression having been rel ieved. Twenty-five cases were all given posterior flavectomy. At 1 week to 3 months after operation, 12 patients received anterior cervical discectomy or vertebral gaining decompression with fusion by bone graft. Results The time for flavectomy was from 60 to 180 minutes, with an average of 95 minutes. The blood loss during operation was from 90 to 360 mL, with an average of 210 mL. The dura maters were lacerated by knife tips during operation with the cervical vertebrae in hyperflexion in 2 cases. Immediate suture and repair were performed and there were no postoperative cerebrospinal fluid leakage. All the incisions healed by first intension after operation. All of the 25 cases were followed up from 2 to 10 years, with an average of 3 years and 9 months. All patients had no compl ication of axial symptoms, and no restenosis at their operation site of cervical canal stenosis. The section area ratios of functional spinal canal to spinal cord were 1.12 ± 0.07 before operation and 2.11 ± 0.19 at 24 months after operation, showing significant difference (P lt; 0.05). The range of motion of cervical vertebrae was (39.4 ± 3.2)º befeore operation and (42.1 ± 2.9)° at 24 months after operation in 13 cases without anterior cervical discectomy fusion, showing no significant difference (P gt; 0.05); was (34.3 ± 3.4)° before operation and (29.2 ± 3.6)° at 24 months after operation in 12 cases with anterior cervical discectomy fusion, showing significant difference (P lt; 0.05). The bone graft achieved bony union 3-5 months after operation (average 3.8 months). The Japanese Orthopaedic Association (JOA) scores were 7.9 ± 2.2 before operation and 15.6 ± 1.4 at 24 months after operation, showing significant difference (P lt; 0.05), with an average improvement rate of 86.3%. Conclusion Cervical flavectomy could rel ieve compression to spinal cord and nerves caused by the flaval l igament hypertrophy without damaging the normal integral ity of bony canal, thus avoiding the compl ication of axial symptoms and so on which are encountered in open-door expansile cervical laminoplasty.
Objective To evaluate the cl inical results of posterior microendoscopic foraminotomy in the treament of cervical radiculopathy and cervical intervertebral disc protrusion. Methods From February 2004 to June 2007, 24 cases of cervical radiculopathy received posterior microendoscopic foraminotomy. There were 16 males and 8 females, aging 42-68 years (59 years on average), including 16 cases of cervical radiculopathy and 8 cases of cervical intervertebral disc protrusion.The course of disease was 6-15 months. The affected intervertebral discs were C4, 5 in 8 cases, C5, 6 in 12 cases, and C6, 7 in 4 cases. The radiological examinations showed that 8 protrusions included 6 soft tissue protusions and 2 rigid tissue protusions, and that cervical radiculopathy were caused by yellow l igament hypertrophy, Luschka’s joint hyperplasia, and abnormal position of facet joint. According to Japanese Orthopedic Association (JOA), the score before operation was (12.60 ± 1.52) points. Results The operation time was 90 to 120 minutes (100 minutes on average), the bleeding during operation was 100 to 150 mL (120 mL on average). Nerve root pain were rel ieved completely in 19 cases and were rel ieved partly in 4 cases. One case of calcified nucleus pulposus had neurological traction injury and recovered completely after 3 months. All cases were followed up 24-36 months (28 months on average). The radiological examinations after operation showed the intervertebral disc site was decompressed completely and the height of intervertebral disc and the cervical segmental al ignment were normal. At 24 months postoperatively, the JOA score was (16.10 ± 0.29) points, showing significant difference when compared with that of preoperation (P lt; 0.01). Conclusion The posterior microendoscopic foraminotomy can get to the operation site with miniincision, decrease tissue damage during operation, and avoid narrow intervertebral space, so it has satisfactory cl inical results.