Frank P. Cammisa

STUDY DESIGN: Retrospective review of a large series of patients who underwent spinal surgery at a single institution during a 10-year period. OBJECTIVES: To further clarify the frequency of incidental durotomy during spine surgery, its treatment, associated complications, and results of long-term clinical follow-up. SUMMARY OF BACKGROUND DATA: Incidental durotomy is a relatively common occurrence during spinal surgery. There remains significant concern about it despite reports of good associated clinical outcomes. There have been few large clinical series on the subject. METHODS: A retrospective review was conducted of clinical and surgical records and radiographic data for consecutive patients who underwent spinal surgery performed by the two senior surgeons from January 1989 through December 1998. RESULTS: A total of 2144 patients were reviewed, and 74 were found to have dural tears occurring during or before surgery. Incidental durotomy occurred at the time of surgery in 66 patients (3.1% overall incidence). Incidence varied according to the specific procedure performed but was highest in the group that underwent revision surgery. The incidence of clinically significant durotomies occurring during surgery but not identified at the time was 0.28%. All dural tears that occurred during surgery and were recognized (60 of 66) were repaired primarily. Pseudomeningoceles developed in five of the remaining six patients. All six patients had subsequent surgical repair of dural defects because of failure of conservative therapy. A mean follow-up of 22.4 months was available and showed good long-term clinical results for all patients. CONCLUSIONS: Incidental durotomy, if recognized and treated appropriately, does not lead to long-term sequelae.

Between 1991 and 1992, 103 consecutive patients (average age, 65 years) underwent decompressive surgery for treatment of typical lumbar spinal stenosis. Clinical results at 1-year followup revealed that four patients had revision surgery. At 2- to 5-years followup, there were no additional revision surgeries. Two patients underwent revision surgery for a deep infection, and two underwent revision surgery for a superficial infection. Outcome results showed that 77 patients completed the questionnaire, 15 were lost to followup and 11 died. Postoperative results showed that 64 of 77 patients had no or mild pain, 72 of 77 patients stated that they were satisfied or somewhat satisfied with their overall results of surgery, and 73 of 77 were satisfied with pain relief. Younger patients had greater improvement in function and a greater reduction in severity scores. However, satisfaction was similar in both groups. Survivorship results (failure was revision surgery) showed at the end of 4 years, a patient had a 95% chance of not having revision surgery. Statistically, there was no association between outcome and cofactors such as scoliosis, spondylolisthesis, number of levels decompressed, discectomy, or smoking. Satisfaction rates for older patients were similar to patients younger than 65 years although physical function scores and severity scores were less.

Two hundred twenty-four consecutive patients underwent elective posterior lumbar spinal surgery over a 3 1/2-year span at the University of Miami/Jackson Memorial Medical Center. Patients ranged in age from 17 to 87 years, and 58% were male. Fifty-eight patients underwent revision surgery, and 65 patients required fusions, including 35 necessitating internal fixation. One hundred seventy-four patients (78%) were requested to participate in a preoperatively donated autologous blood (PDAB) program. Six of these patients were excluded from participation, and 168 patients banked 425 U of autologous blood. Eighty percent of the patients participating in the PDAB program received some or all of their donated blood. Intraoperative blood salvage was used in 37% of cases. Seven patients received homologous blood: four in addition to salvaged and donated blood, two that were unable to donate blood due to positive hepatitis B serology, and one erroneously. The combined use of PDAB and intraoperative salvage program allowed autologous blood replacement to meet the total transfusion requirements of 96% of the patients who predeposited blood, including 94% of those undergoing spinal fusions. Autologous blood comprised 99% of the total blood replacement used in this series, and 95% of the patients requiring blood transfusions received only autologous blood. Establishment of a protocol judiciously using PDAB in conjunction with intraoperative blood salvage can result in virtual elimination of the need for homologous blood transfusion in elective lumbar spine surgery.