Microdiscectomy for symptomatic lumbar disc herniations in young, active patients with a preponderance of leg pain who have failed nonoperative treatment demonstrated a high success rate based on validated outcome measures, patient satisfaction, and return to active duty. Patients with disc herniations at the L5-S1 level had significantly better outcomes than did those at the L4-L5 level. Patients with sequestered or extruded lumbar disc herniations had significantly better outcomes than did those contained herniations. Patients with contained disc herniations, a predominance of back pain, on restricted duty and smoking should be counseled before surgery of the potential for less satisfaction, poorer outcomes scores, and decreased return to duty rates.

Our study has shown that when EMF tracking was used for image-guided lumbar pedicle screw placement, accuracy was improved and the incidence and degree of cortical perforations that may place neurovascular structures at risk was also reduced. Current system requirements for set-up and image acquisition, however, do add time to the procedure, and when factored in, do not yet result in a decrease in the use of fluoroscopy or screw insertion time.

Twenty volunteers (40 feet) with no prior foot injury underwent standardized abduction stress and standing AP radiographs. Subsequently, the Lisfranc and dorsal tarsometatarsal ligaments in nine feet from cadavers were sectioned in a varying sequential manner, and interval standardized radiographs of abduction stress and AP simulated weightbearing were obtained. On abduction stress radiographs in 39 of 40 feet of volunteers and nine of nine feet of cadavers before sectioning, a line tangential to the medial aspect of the navicular and medial cuneiform (medial column line) intersected the base of the first metatarsal. Combining the sectioning of the Lisfranc and dorsal tarsometatarsal ligaments produced a disruption of the medial column line in all feet from cadavers. Disruption of this medial column line may be a simple and valuable diagnostic tool for determining significant ligamentous injury to the tarsometatarsal interval.

Our study has shown that EMF image-guided thoracic pedicle screw placement results in a similar incidence of safely placed screws as does conventional fluoroscopy. When set-up time and image-capture time were factored in for image guidance, the average time to insert a pedicle screw was equal for both techniques. The use of EMF image guidance significantly reduced fluoroscopic time and thus radiation exposure per screw compared with conventional fluoroscopic techniques.

No abstract