MRI Radiological Predictors of Requiring Microscopic Lumbar Discectomy After Lumbar Disc Herniation.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate radiological differences in lumbar disc herniations (herniated nucleus pulposus [HNP]) between patients receiving microscopic lumbar discectomy (MLD) and nonoperative patients. METHODS: Patients with primary treatment for an HNP at a single academic institution between November 2012 to March 2017 were divided into MLD and nonoperative treatment groups. Using magnetic resonance imaging (MRI), axial HNP area; axial canal area; HNP canal compromise; HNP cephalad/caudal migration and HNP MRI signal (black, gray, or mixed) were measured. T test and chi-square analyses compared differences in the groups, binary logistic regression analysis determined odds ratios (ORs), and decision tree analysis compared the cutoff values for risk factors. RESULTS: A total of 285 patients (78 MLD, 207 nonoperative) were included. Risk factors for MLD treatment included larger axial HNP area (P < .01, OR = 1.01), caudal migration, and migration magnitude (P < .05, OR = 1.90; P < .01, OR = 1.14), and gray HNP MRI signal (P < .01, OR = 5.42). Cutoff values for risks included axial HNP area (70.52 mm2, OR = 2.66, P < .01), HNP canal compromise (20.0%, OR = 3.29, P < .01), and cephalad/caudal migration (6.8 mm, OR = 2.43, P < .01). MLD risk for those with gray HNP MRI signal (67.6% alone) increased when combined with axial HNP area >70.52 mm2 (75.5%, P = .01) and HNP canal compromise >20.0% (71.1%, P = .05) cutoffs. MLD risk in patients with cephalad/caudal migration >6.8 mm (40.5% alone) increased when combined with axial HNP area and HNP canal compromise (52.4%, 50%; P < .01). CONCLUSION: Patients who underwent MLD treatment had significantly different axial HNP area, frequency of caudal migration, magnitude of cephalad/caudal migration, and disc herniation MRI signal compared to patients with nonoperative treatment.

Implantation of a bone-anchored annular closure device in conjunction with tubular minimally invasive discectomy for lumbar disc herniation: a retrospective study.

BACKGROUND: Minimally invasive techniques for lumbar discectomy have been recommended as superior to open techniques due to lower blood loss, lower rates of infection and shorter recovery. There are, however, concerns that this approach does not sufficiently remove the herniated nuclear material, thus leaving the patient susceptible to reherniation requiring reoperation. The purpose of this study was to examine the safety and viability of an annular closure device in limiting reherniation and reoperation in a cohort of patients undergoing minimally invasive lumbar discectomy with the assistance of an annular closure device. METHODS: We retrospectively analysed the results from patients treated by a single surgeon between March 2011 and December 2017. All patients had been diagnosed with a large (≥ 5 mm) defect and were treated via minimally invasive surgical techniques. Outcomes included demographic data, the procedural duration and the rates of symptomatic reherniation and reoperation. RESULTS: 60 patients were included in the study. The mean age was 42 years (range: 19-66); mean BMI was 24.1 (range: 16.7-36.3). Mean surgical duration was 29 min (range: 16-50). Reoperation was required in 5% (3/60) of patients, although only 3% (2/60) experienced symptomatic reherniation at the index level. No other complications were reported. CONCLUSIONS: In our study, the use of an annular closure device during minimally invasive lumbar discectomy in a population of patients with large herniations was associated with low rates of reherniation and reoperation at the index level. While more research is required, the results of this study demonstrate the safety and viability of the annular closure device as an adjunct to minimally invasive discectomy.

The manubrium as an external guide for centralizing anterior cervical plates: technique tips and initial experience.

STUDY DESIGN: Technique tips and retrospective review of prospectively collected data. OBJECTIVE: To describe a technique for centralizing cervical plates using the center of the manubrium as a primary external guide and its alignment with the mandible as a secondary guide. SUMMARY OF BACKGROUND DATA: Proper alignment of cervical plates is desirable to avoid improper placement of screws and possibly altered biomechanical performance. Large body habitus may portend suboptimal exposure, a limited utility of skin surface landmarks for level determination, and may make it difficult to reliably centralize plates in the coronal plane during anterior cervical surgery. METHODS: We describe a technique that uses the center of the manubrium to determine the midline of the cervical spine and align a line drawn through the manubrium with the center of the mandible to provide a central axis for placing cervical plates along the entire cervical spine. We used anteroposterior fluoroscopy to validate that a line from the middle of the manubrium to the mandible bisected the spinous processes and midline of the vertebral bodies. We prospectively collected data on 39 consecutive patients undergoing anterior cervical discectomy and fusion with cervical plates using this technique. RESULTS: The mean amount of angulation and translation about a midline axis were 2.24 degrees +/- 1.49 degrees and 1.04 +/- 0.86 mm, respectively. There were no statistical differences among 1-level, 2-level, and 3-level fusions (P > 0.05). The intraobserver correlation coefficient for the measurement technique was R = 0.90 (P = 0.0016). CONCLUSION: We validated that the midline of the cervical spine is in line with a straight bovie cord connecting the midline of the manubrium to the midline of the mandible using anteroposterior fluoroscopy. Using this line, we prospectively centered cervical plates with no significant difference between levels. These data may also serve as a benchmark for assessing cervical plate alignment.

Anterior cervical decompression and fusion with plate fixation as an outpatient procedure.

BACKGROUND CONTEXT: Outpatient cervical spine surgery has previously been described for posterior laminoforaminotomy and anterior microdiscectomy with allograft fusion. Anterior cervical discectomy and fusion (ACDF) with plate fixation has not, to our knowledge, been described as an outpatient procedure. PURPOSE: The objective of this study was to evaluate the safety and feasibility of ACDF with instrumentation when performed as an outpatient in a free-standing ambulatory surgical center. Additionally, the authors sought to determine any patient selection bias and its effect on outcome. STUDY DESIGN: This study is a retrospective medical record review. PATIENT SAMPLE: The sample included all patients who underwent one or two level ACDF with plate fixation at levels C4-5 or below as an adjunct to autogenous iliac crest bone graft or structural allograft from 1998 to 2002 by the two senior authors. OUTCOME MEASURES: Complications were assessed clinically with special attention to dysphagia and respiratory complications. Inpatient lengths of stay and postoperative hospital admission or readmission were also measured. METHODS: Thirty consecutive patients were treated at a free-standing ambulatory surgery center, whereas two control groups, each of 30 consecutive patients, had surgery performed in the hospital and were admitted overnight for observation. The first control group consisted of admitted patients before the commencement of patient selection for the outpatient group; the second control group was comprised of admitted patients who had surgery performed concurrently with the outpatient group. The study group was evaluated on the first postoperative day and 3 weeks after surgery. RESULTS: Ninety patients underwent ACDF plate fixation at 140 different levels. Forty patients were treated at one level, and 50 were treated at two levels. The three groups were comparable in age, sex, and body mass index. There were no major complications. Seven patients (13%) had minor postoperative complications among the controls: transient dysphagia in three (5%) and graft donor site pain in four (14%). Three patients (10%) in the outpatient group had minor complications (all had dysphagia). Among the controls, four patients (7%) had increased length of stay owing to complications. Four patients (7%) in the combined control group were readmitted for early complications; no patient was admitted for a complication after outpatient surgery. CONCLUSIONS: In the present study, selection criteria for outpatient surgery included one or two level involvement C4-5 or lower, absence of myelopathy, subjective neck size, and estimated operative time. The data did not otherwise suggest a difference in the surgical populations. The outpatient group had a lower complication rate compared with the controls. This was likely the result of selection bias. Transient dysphagia was the most prevalent complication in the outpatient group.

Manifestations of hereditary multiple exostoses.

The solitary osteochondroma, a common pediatric bone tumor, is a cartilage-capped exostosis. Hereditary multiple exostosis is an autosomal dominant disorder manifested by the presence of multiple osteochondromas. Linkage analysis has implicated mutations in the EXT gene family, resulting in an error in the regulation of normal chondrocyte proliferation and maturation that leads to abnormal bone growth. Although exostoses are benign lesions, they are often associated with characteristic progressive skeletal deformities and may cause clinical symptoms. The most common deformities include short stature, limb-length discrepancies, valgus deformities of the knee and ankle, asymmetry of the pectoral and pelvic girdles, bowing of the radius with ulnar deviation of the wrist, and subluxation of the radiocapitellar joint. For certain deformities, surgery can prevent progression and provide correction. Patients with hereditary multiple exostosis have a slight risk of sarcomatous transformation of the cartilaginous portion of the exostosis.