Regis W. Haid

Anterior cervical plating enhances arthrodesis after discectomy and fusion with cortical allograft.

OBJECTIVE Anterior plate fixation has gained widespread acceptance for the treatment of cervical spondylosis, theoretically enhancing the rate of arthrodesis. There are few studies comparing fusion rates after anterior cervical discectomy and fusion (ACDF) with and without a plate. The purpose of this study was to evaluate the efficacy of anterior cervical plating for fusion enhancement after one- and two-level ACDF with cortical allograft. METHODS A retrospective review was performed with 251 patients who underwent one- or two-level ACDF with cortical allograft and plate stabilization between 1993 and 1999. An independent surgeon reviewer determined fusion status and complications. A successful fusion was defined by the absence of lucency around the graft, evidence of bridging bone between the endplate and the graft, and the absence of movement on dynamic imaging scans. Follow-up data, ranging from 9 months to 3.6 years, were available for 233 patients. A control group of 289 patients who underwent ACDF without plating was described in a previously published report by the senior author (RWH). Therefore, a total of 540 patients were evaluated for determination of the efficacy of anterior cervical plating with cortical allograft bone. Statistical significance was determined by &khgr;2 test. RESULTS The fusion rates for one- and two-level ACDF with anterior fixation were 96 and 91%, respectively, compared with 90 and 72% for one- and two-level ACDF without anterior fixation. The observed increases in fusion rates for both one- and two-level procedures proved to be statistically significant (P < 0.05). There were no recorded infectious, neurological, or graft-related complications among the cohort treated with anterior cervical plating. Compared with the results for the cohort treated without anterior cervical plates, there was a statistically significant decrease in the graft-related complication rate with the application of plates (P < 0.001). Two patients who received plates were noted to have adjacent-segment degenerative changes that required surgical intervention. No hardware fractures were noted; however, one patient was noted to have a single displaced screw, without clinical consequences. CONCLUSION The use of anterior cervical plating after one- and two-level ACDF with allograft cortical bone significantly enhanced arthrodesis. The improved fusion rate and negligible complication rate associated with anterior cervical plating are compelling factors justifying its use in the treatment of cervical spondylosis.

C1-C2 transarticular screw fixation for atlantoaxial instability : a 6-year experience

OBJECTIVEWe review a 6-year, single-center experience using the technique of C1–C2 transarticular screw fixation for atlantoaxial instability in 75 consecutive operations. METHODSThe study group was composed of 43 men and 32 women, with a mean age of 44 years (range, 8–76 yr). Each patient had documented atlantoaxial instability. In 28 patients (37%), atlantoaxial instability was a result of trauma; in 22 patients, (29%), it was a result of rheumatoid arthritis; in 16 patients (21%), it was a result of prior surgery; and in 9 patients (12%), it was a result of congenital abnormalities. All patients underwent stabilization with C1–C2 transfacetal screws and a posterior interspinous construct. Nine patients had unilateral screws placed. Postoperatively, the patients were maintained in a rigid cervical orthosis for a mean of 11 weeks (range, 8–15 wk); five patients were immobilized with halo fixation for a mean of 13 weeks (range, 10–16 wk). The mean follow-up period was 2.4 years (range, 1–5.5 yr). RESULTSOsseous fusion was documented in 72 patients (96%). There were no hardware failures; however, three patients developed pseudarthrosis. Two superficial wound infections (one at the graft site and one at the cervical incision site) required antibiotic therapy. Four patients had transient suboccipital hypesthesia. No instances of an errant screw, dural laceration, or injury to the vertebral artery, spinal cord, or hypoglossal nerve were noted. CONCLUSIONC1–C2 transarticular screw fixation supplemented with an interspinous construct yielded a 96% fusion rate, with a low incidence of complications. We attribute our successful outcomes to careful preoperative assessment and meticulous surgical technique.

Comparison of the Mini-open versus Laparoscopic Approach for Anterior Lumbar Interbody Fusion: A Retrospective Review

OBJECTIVE The anterior lumbar interbody fusion (ALIF) procedure has become an accepted fusion technique for treating patients with degenerative disorders of the lumbar spine. Many consider laparoscopic ALIF to be the least invasive approach. A modification of the open laparotomy—the “mini-open” approach—is an attractive alternative. In this retrospective review, a comparison of these two ALIF approaches is presented. METHODS We conducted a retrospective review of 98 patients who underwent ALIF procedures between 1996 and 2001 in which either a mini-open or a laparoscopic approach was used. Patient demographics, intraoperative parameters, length of hospitalization, and technique-related complications associated with the use of these two approaches were compared. The subset of patients who underwent L5–S1 ALIF procedures was analyzed separately. Statistical analysis was conducted with &khgr;2 and Student’s paired t tests. RESULTS Between 1996 and 2001, a total of 98 patients underwent ALIF. A laparoscopic approach was used in 47 of these patients, and the mini-open technique was used in the other 51 patients. Operative preparation and procedure time were longer with the use of a laparoscopic approach, and significantly greater during L5–S1 ALIF procedures (P < 0.05). A marginal but significant increase in length of stay was observed after mini-open ALIF procedures (P < 0.05). The immediate postoperative complication rate was greater after mini-open ALIF procedures, 17.6 versus 4.3% (P < 0.05); however, the rate of retrograde ejaculation was higher in the laparoscopic group, 45 versus 6% (P < 0.05). CONCLUSION Both the laparoscopic and mini-open techniques are effective approaches to use when performing ALIF procedures. On the basis of the data obtained in this retrospective review, the laparoscopic approach does not seem to have a definitive advantage over the mini-open exposure, particularly in an L5–S1 ALIF procedure. In our opinion, the mini-open approach possesses a number of theoretical advantages; however, the individual surgeon’s preference ultimately is likely to be the dictating factor.

C1-C2 transarticular screw fixation : technical aspects

OBJECTIVEI review posterior atlantoaxial fusion with transarticular screw fixation, including indications, complications, and operative technique, emphasizing my experience. METHODSThe indications for C1–C2 transarticular screw fixation include traumatic injuries to the atlantoaxial complex, instability resulting from inflammatory disease (rheumatoid arthritis), and congenital abnormalities (os odontoideum). All patients underwent stabilization using cannulated C1–C2 transfacetal screws by the method described by Magerl. Supplemental interspinous fusion with bicortical autologous iliac crest graft and titanium cable was used to restore the posterior tension band by use of the method described by Sonntag’s group. Preoperatively, all patients underwent imaging with plain radiographs, magnetic resonance imaging, and axial computed tomography. Patients were maintained in a rigid cervical orthosis postoperatively. RESULTSMeasures used to improve safety and efficacy include patient positioning, fluoroscopic guidance, preoperative magnetic resonance imaging, axial computed tomography, and open reduction of C1–C2 subluxation before screw passage. In this series of 75 patients, fusion was obtained in 72 patients (96%). There were no instances of vertebral artery injury, errant screw placement, instrumentation failure, dural laceration, spinal cord injury, or hypoglossal nerve injury. CONCLUSIONC1–C2 transarticular screw fixation with a posterior tension band construct provides excellent fusion rates with few perioperative complications. Preoperative imaging and meticulous surgical technique improve outcomes.

Treatment of degenerative cervical disc disease

The different clinical presentations and treatment options available to treat neck pain from degenerative disc disease have been discussed. With proper patient selection, good correlation between clinical and radiographic findings, and selecting the correct procedure for each patient, surgical treatment of cervical radiculopathy and myelopathy can be one of the most gratifying operations performed in neurosurgery.

Corpectomy and stabilization with methylmethacrylate in patients with metastatic disease of the spine: a technical note.

Corpectomy with methylmethacrylate reconstruction and stabilization in patients with metastatic disease of the spine has been performed for several years. Stainless steel Steinmann pins or K-wires are commonly used to facilitate fixation of the acrylic to the vertebral bodies above and below the resection site. The use of these ferromagnetic substances precludes the optimal use of magnetic resonance imaging in the postoperative period. We now report the use of commercially available titanium screws in conjunction with the methylmethacrylate to eliminate this problem and provide for improved postoperative imaging.