Follow-up of Patients With Delayed Union After Posterior Fusion With Pedicle Screw Fixation

Abstract

Bone union occurred more than 2 years after posterior fusion with PS in about 30% of patients with delayed union. Its occurrence was related to the intervertebral range of motion and disc height. Firm bone union was not necessarily essential for good clinical results.

Radiographic Changes in Patients with Pseudarthrosis After Posterior Lumbar Interbody Arthrodesis Using Carbon Interbody Cages

“…Tokuhashi et al concluded that osseous union occurred more than two years after posterior arthrodesis with pedicle screws in approximately 30% of patients with delayed union and that the radiolucent zones disappeared over time in approximately two-thirds of the patients 10,11 . In the present study, the mean grades for screw and cage radiolucent zones deteriorated up to one year, when the maximum radiolucent zones occurred, and then improved up to four or five years, with the increases up to three years reaching significance.…”

“…Fusion status is described by terms such as successful fusion, pseudarthrosis, nonunion, and delayed union; however, these terms are not clearly defined. Tokuhashi et al declared that it is not reasonable to define a failure to achieve osseous union within one year after posterior spinal surgery as pseudarthrosis, and the condition should instead be called delayed union 10 . McAfee pointed out that, in the absence of evidence of successful fusion, it is useful to think of spinal fusion status as ''indeterminate'' in the first two postoperative years 1 .…”

“…Conversely, motion on radiographs, the absence of continuous trabecular osseous bridging, and the presence of radiolucent zones surrounding the pedicle screws and interbody cages on postoperative radiographs or CT scans have each been widely accepted as definite indicators of pseudarthrosis after these procedures 8 . However, Tokuhashi et al reported that the postoperative pedicle screw radiolucent zone disappeared over time in approximately two-thirds of patients treated with posterior lumbar arthrodesis and its presence did not necessarily indicate permanent pseudarthrosis 10,11 . We therefore conducted a prospective study to determine the natural course that can be expected when pseudarthrosis follows posterior lumbar interbody arthrodesis using current pedicle screws and metal or nonmetal interbody cages.…”

Anterior stand-alone fusion revisited: a prospective clinical, X-ray and CT investigation

“…Finally, the CT scans in the pseudarthrosis group were performed after a premature FU of only 9.9 months following the index surgery in comparison to 20.4 months in the cohort of patients without pseudarthrosis. Previous studies have, however, pointed out that significantly longer FU is required for an appropriate fusion assessment, and in these particular cases, the term 'delayed union' may be more appropriate than the term 'pseudarthrosis' [71][72][73].…”

Correlation Between Quality of Life and Osteolysis Around Lumbar Pedicle Screws

“…16 It is known that fusion failure of the arthrodesis can be a source of pain, according to some authors, but there are few reports in the literature, and there is no definitive conclusion as to whether there is a direct relationship between the presence of a radiolucent halo and one of the unfavorable clinical outcomes, such as the presence of postoperative pain. 8,18 Quality of life refers to the dimensions of life that can be affected by diseases or their treatment. 19 It is known that low back pain has a direct negative impact on the patient's quality of life, and that it is a condition commonly associated with severe pain and great physical, social and psychological disability, [20][21][22] leading to deficits four times greater when compared to the general population, after adjusting for age and comorbidities.…”