Tomohiro Hikata, Kota Watanabe, Nobuyuki Fujita, Akio Iwanami, Naobumi Hosogane, Ken Ishii, Masaya Nakamura, Yoshiaki Toyama and Morio Matsumoto
The object of this study was to investigate correlations between sagittal spinopelvic alignment and improvements in clinical and quality-of-life (QOL) outcomes after lumbar decompression surgery for lumbar spinal canal stenosis (LCS) without coronal imbalance.
The authors retrospectively reviewed data from consecutive patients treated for LCS with decompression surgery in the period from 2009 through 2011. They examined correlations between preoperative or postoperative sagittal vertical axis (SVA) and radiological parameters, clinical outcomes, and health-related (HR)QOL scores in patients divided according to SVA. Clinical outcomes were assessed according to Japanese Orthopaedic Association (JOA) and visual analog scale (VAS) scores. Health-related QOL was evaluated using the Roland-Morris Disability Questionnaire (RMDQ) and the JOA Back Pain Evaluation Questionnaire (JOABPEQ).
One hundred nine patients were eligible for inclusion in the study. Compared to patients with normal sagittal alignment prior to surgery (Group A: SVA < 50 mm), those with preoperative sagittal imbalance (Group B: SVA ≥ 50 mm) had significantly smaller lumbar lordosis and thoracic kyphosis angles and larger pelvic tilt. In Group B, there was a significant decrease in postoperative SVA compared with the preoperative SVA (76.3 ± 29.7 mm vs 54.3 ± 39.8 mm, p = 0.004). The patients in Group B with severe preoperative sagittal imbalance (SVA > 80 mm) had residual sagittal imbalance after surgery (82.8 ± 41.6 mm). There were no significant differences in clinical and HRQOL outcomes between Groups A and B. Compared to patients with normal postoperative SVA (Group C: SVA < 50 mm), patients with a postoperative SVA ≥ 50 mm (Group D) had significantly lower JOABPEQ scores, both preoperative and postoperative, for walking ability (preop: 36.6 ± 26.3 vs 22.7 ± 26.0, p = 0.038, respectively; postop: 71.1 ± 30.4 vs 42.5 ± 29.6, p < 0.001) and social functioning (preop: 38.7 ± 18.5 vs 30.2 ± 16.7, p = 0.045; postop: 67.0 ± 25.8 vs 49.6 ± 20.0, p = 0.001), as well as significantly higher postoperative RMDQ (4.9 ± 5.2 vs 7.9 ± 5.7, p = 0.015) and VAS scores for low-back pain (2.68 ± 2.69 vs 3.94 ± 2.59, p = 0.039).
Preoperative sagittal balance was not significantly correlated with clinical or HRQOL outcomes after decompression surgery in LCS patients without coronal imbalance. Decompression surgery improved the SVA value in patients with preoperative sagittal imbalance; however, the patients with severe preoperative sagittal imbalance (SVA > 80 mm) had residual imbalance after decompression surgery. Both clinical and HRQOL outcomes were negatively affected by postoperative residual sagittal imbalance.
Narihito Nagoshi, Osahiko Tsuji, Daisuke Nakashima, Ayano Takeuchi, Kaori Kameyama, Eijiro Okada, Nobuyuki Fujita, Mitsuru Yagi, Morio Matsumoto, Masaya Nakamura and Kota Watanabe
Intramedullary cavernous hemangioma (CH) is a rare vascular lesion that is mainly characterized by the sudden onset of hemorrhage in young, asymptomatic patients, who then experience serious neurological deterioration. Despite the severity of this condition, the therapeutic approach and timing of intervention for CH remain matters of debate. The aim of this study was to evaluate the clinical characteristics of CH patients before and after surgery and to identify prognostic indicators that affect neurological function in these patients.
This single-center retrospective study included 66 patients who were treated for intramedullary CH. Among them, 57 underwent surgery and 9 patients received conservative treatment. The authors collected demographic, symptomology, imaging, neurological, and surgical data. Univariate and multivariate logistic regression analyses were performed to identify the prognostic indicators for neurological function.
When comparing patients with stable and unstable gait prior to surgery, patients with unstable gait had a higher frequency of hemorrhagic episodes (52.4% vs 19.4%, p = 0.010), as assessed by the modified McCormick Scale. The lesion was significantly smaller in patients who underwent conservative treatment compared with surgery (2.5 ± 1.5 mm vs 5.9 ± 4.1 mm, respectively; p = 0.024). Overall, the patients experienced significant neurological recovery after surgery, but a worse preoperative neurological status was identified as an indicator affecting surgical outcomes by multivariate analysis (OR 10.77, 95% CI 2.88–40.36, p < 0.001). In addition, a larger lesion size was significantly associated with poor functional recovery in patients who had an unstable gait prior to surgery (8.6 ± 4.5 mm vs 3.5 ± 1.6 mm, p = 0.011).
Once a hemorrhage occurs, surgical intervention should be considered to avoid recurrence of the bleeding and further neurological injury. In contrast, if the patients with larger lesion presented with worse preoperative functional status, surgical intervention could have a risk for aggravating the functional deficiencies by damaging the thinning cord parenchyma. Conservative treatment may be selected if the lesion is small, but regular neurological examination by MRI is needed for assessment of a change in lesion size and for detection of functional deterioration.
Sanjeev Ariyandath Sreenivasan, Kanwaljeet Garg, Manmohan Singh and Poodipedi Sarat Chandra
Satoshi Nori, Akio Iwanami, Akimasa Yasuda, Narihito Nagoshi, Nobuyuki Fujita, Tomohiro Hikata, Mitsuru Yagi, Takashi Tsuji, Kota Watanabe, Suketaka Momoshima, Morio Matsumoto, Masaya Nakamura and Ken Ishii
A number of studies have reported that surgery for cervical intramedullary tumors via the posterior approach can result in postoperative sagittal malalignment of the cervical spine; however, the risk factors remain unclear. The purpose of this study was to investigate the changes in cervical spinal alignment after surgery for cervical intramedullary tumors in adults and to elucidate the risk factors for cervical spinal sagittal misalignment.
Data for the period from April 2001 to December 2011 for all adults who had undergone surgery for cervical intramedullary spinal cord tumors at a single institution were retrospectively analyzed to determine the postoperative changes in cervical spine alignment. Patients younger than 20 years of age and those who required postoperative radiotherapy were excluded from the study. Patients were divided into 2 groups according to tumor location: upper tumor (U) group, in which the central region of the tumor was above the C-5 level; and lower tumor (L) group, in which the central region of the tumor was at or below the C-5 level. Changes in alignment of the cervical spine were measured on plain lateral radiographs. Data on atrophy of the deep extensor muscles (DEMs), tumor location, detachment of the DEMs from the C-2 spinous process, the C2–7 angle before surgery, patient age at surgery, tumor histology, patient sex, tumor size, and number of laminae affected were reviewed for each patient, and the correlation of each of these factors with cervical spinal malalignment was evaluated using statistical analysis.
The 54 adults eligible for analysis had a mean age of 49.1 years. Ependymoma was the most common cervical intramedullary tumor (63.0%) in this series. In the tumor location U group, the kyphotic angle of the C2–7 spinal segments increased after surgery (−5.8° ± 2.8°). In contrast, in the L group, the C2–7 lordotic angle increased after surgery (6.4° ± 2.6°). In the univariate analysis, atrophy of the DEMs, detachment of the DEMs from the C-2 spinous process, and an upper cervical location of the tumor were identified as factors significantly correlated with the development of cervical spinal kyphosis after surgery. Multiple linear regression analysis revealed the following as risk factors for kyphotic change of the cervical spine after surgery: 1) atrophy of the DEMs after surgery (β = −0.54, p < 0.01), and 2) detachment of the DEMs from the C-2 spinous process (β = −0.37, p < 0.01).
Atrophy of the DEMs after surgery and detachment of the DEMs from the C-2 spinous process are directly related to the risk of cervical spinal kyphosis after surgery for cervical intramedullary tumors in adults. Therefore, preservation of the DEMs, especially those attached to the C-2 spinous process, is important for the prevention of kyphotic malalignment of the cervical spine after surgery for intramedullary tumors.