Correct identification of fusion levels in surgical planning for the management of adolescent idiopathic scoliosis is a complex task. Several classification systems and algorithms exist to assist surgeons in determining the appropriate levels to be instrumented. The Lenke classification is the benchmark system. Among the many factors and measurements that are taken into account when selecting the proper upper instrumented vertebra and lower instrumented vertebra are planning for selective fusion; preserving motion segments; preventing proximal and/or distal junctional kyphosis, shoulder imbalance, and neck pain; and maintaining short fusion lengths. Existing treatment algorithms do not account for every exception, and further research is required to improve long-term surgical outcomes.
Introduction Aim of this study was to analyze the rate of tether breakages after lumbar vertebral body tethering (VBT) and to study the effects and possible benefits of the use of a 2-tether construct. Tether breakage is a known mechanical complication after VBT. However, the literature only refers to thoracic VBT, and no data on the breakage rate or 2-tether construct after lumbar VBT are available. Materials and methods Patients who underwent lumbar VBT with lowest instrumented vertebra at L3 or L4 and had a 1-year follow-up were included. Radiologic data were obtained preoperatively, at the 1st standing X-ray and at the 1-year follow-up to study breakage rate, loss of correction and lumbar lordosis in 1-and 2-tether constructs. Results Data from 30 patients (mean age 14.7 ± 1.8) were available, 12 with double tether. Double tether did not decrease lumbar lordosis. The breakage rate was 24% in segments instrumented with a single tether and 16% in segments instrumented with a double tether (OR 1.6, p = 0.4). Lumbar loss of correction was 10° ± 6.8° in the entire cohort and 12.1° ± 5.4° in patients with a breakage (p = 0.2). Revision rate was 10%, due to tether breakage and loss of correction. Conclusion Breakage rate after lumbar VBT is high, but was improved with the use of a 2-tether construct. Despite tether breakage, loss of correction was limited and the revision rate low. The use of a double tether does not have a kyphotic effect on the lumbar spine.
Educational Objectives
1.
Explain the etiology, epidemiology and clinical presentation of quadriceps tendon injuries.
2.
Describe the role of ultrasound and magnetic resonance imaging in the diagnosis of quadriceps tendon ruptures.
3.
Discuss the surgical techniques for management of acute and chronic quadriceps tendon ruptures.
4.
Restate the complications and outcomes following repair of quadriceps tendon ruptures.
Quadriceps tendon ruptures are uncommon injuries. Degenerative changes in the tendon are felt to be an important precondition for rupture. We retrospectively reviewed 45 quadriceps tendon ruptures in 42 patients. Quadriceps tendon ruptures occurred most often in the sixth and seventh decade of life. Men were affected six times as often as women. A tissue sample from the rupture-zone was obtained in 22 cases and histologic analysis was performed. Degenerative changes were present in only 14 (64%) of the 22 samples. We observed an increasing ratio of degenerative to nondegenerative tendons with increasing patient age. Our data suggests that quadriceps tendon rupture, especially in younger patients, can occur in the absence of pathologic tendon degeneration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.