Pseudarthrosis of the lumbar spine - Outcome after circumferential fusion

Study Design. Twenty-five patients with a pseudarthrosis after previous spinal fusion surgery were reviewed after a circumferential fusion was performed. Objectives. To determine the fusion rate and its relation to outcome, i.e., pain reduction and return to work, and associated complications. Summary of Background Data. Circumferential fusion has become a common procedure with more patients undergoing multiple operations. The operation is thought to improve the fusion rate with a low complication rate. However, the procedure has not been evaluated specifically for the management of pseudarthrosis. Methods. Twenty-five patients were reviewed regarding age, gender, smoking status, previous back surgeries, extent of leg and back pain, occupation, levels of surgery, type of instrumentation, blood loss, and complications. A minimum follow-up period of 2 years included evaluation of radiographs, pain levels, medication, and return to work. Results. Twenty percent of patients were heavy smokers. An average of 2.2 previous procedures had been performed, and the average follow-up period was 2-7 years. Eighty percent of patients underwent multiple-level fusions. A solid fusion was achieved in 100%. Complications included two painful instrumentation devices requiring removal, one retroperitoneal hematoma, one anterior abdominal wall dehiscence, and one case of pneumonia. Pain scores improved from 7.4 to 4.7 for back pain, and 5.4 to 2.8 for leg pain, respectively. Both improvements were statistically significant (P < 0.01 and 0.003, respectively). However, only 52% of patients reduced their pain by a full category. Forty-one percent were still taking narcotics intermittently or consistently, and 53% returned to work or were actively seeking employment. Discussion. A fusion rate of 100% was noted in the face of factors often placing patients at high risk for developing a pseudarthrosis, namely multiple levels of previous spinal surgery, including previous pseudarthrosis, and a habit of heavy smoking. Complications were few. However, the satisfactory outcome rate was only somewhat better than 50%, based on a lack of substantial pain improvement and return to work.