Neurological manifestations of thoracic myelopathy.

INTRODUCTION: Investigation of preoperative manifestations of thoracic myelopathy in a large population has not been reported. The aim of this study was to identify symptoms specific to anatomical pathology or compressed segments in thoracic myelopathy through investigation of preoperative manifestations. MATERIALS AND METHODS: Subjects were 205 patients [143 men, 62 women; mean age, 62.2 (range 21-87 years)] with thoracic myelopathy who underwent surgery at our affiliate institutions from 2000 to 2011. The disease distribution included ossification of the ligamentum flavum (OLF) in 106 patients, ossification of the posterior longitudinal ligament (OPLL) in 17, OLF with OPLL in 17, intervertebral disc herniation (IDH) in 23, OLF with IDH in 3, and spondylosis in 39. We assessed (1) initial and preoperative complaints, (2) neurological findings, (3) Japanese Orthopaedic Association scores (JOA, full score, 11 points), (4) the compressed segments, and (5) preoperative duration. Multivariate analyses were performed to examine potential relationships between preoperative manifestations and anatomical pathology or compressed segments. RESULTS: The multivariate analyses revealed relationships between lower limb muscle weakness and T10/11 anterior compression; lower limb pain and T11/12 anterior compression; low back pain and T11/12 compression; and hyporeflexia in the patellar tendon reflex/foot drop and T12/L1 anterior compression. CONCLUSION: This study elucidated symptoms specific to anatomical pathology or compressed segments in thoracic myelopathy. These relationships can be helpful in the initial investigation of thoracic diseases, although additional measures such as MRI or CT are necessary for definitive diagnosis.

Laminoplasty for cervical myelopathy caused by subaxial lesions in rheumatoid arthritis.

OBJECT: Although controversy exists regarding surgical treatment for rheumatoid subaxial lesions, no detailed studies have been conducted to examine the efficacy of laminoplasty in such cases. To discuss indications for laminoplasty in rheumatoid subaxial lesions, the authors retrospectively investigated clinical and radiological outcomes in patients who underwent laminoplasty for subaxial lesions. METHODS: Thirty patients (11 men and 19 women) underwent laminoplasty for rheumatoid subaxial lesions. The patients were divided into those with mutilating-type rheumatoid arthritis (RA) and those with nonmutilating-type RA according to the number of eroding joints. As of final follow-up examination laminoplasty resulted in improvement of myelopathy in 24 patients (seven with mutilating- and 17 with nonmutilating-type RA) and transient or no improvement in six (five with mutilating- and one with nonmutilating-type RA). In the group with mutilating-type RA, significantly poorer results were displayed (p < 0.05). In most patients preoperative radiographs demonstrated vertebral slippage less than or equal to 5 mm at only one or two levels. Postlaminoplasty deterioration of subaxial subluxation and unfavorable alignment change occurred significantly more often in patients with mutilating-type RA (p < 0.05). CONCLUSIONS: Patients with nonmutilating-type RA can benefit from laminoplasty for myelopathy due to subaxial lesions.

Sagittal alignment of the subaxial cervical spine after C1-C2 transarticular screw fixation in rheumatoid arthritis.

Several articles reported the association between the development of subaxial kyphosis and the hyperlordotic fixation of C1-C2. However, their patients were heterogeneous in both primary disease and operative procedure. Transarticular screw fixation has become a popular procedure for C1-C2 arthrodesis instead of wiring techniques in which C1-C2 is difficult to fix in the intended alignment. Furthermore, in rheumatoid arthritis (RA) patients, subaxial lesions play an important role in potential subaxial alignment changes. The subaxial influences after C1-C2 transarticular screw fixation in patients with RA are unclear. To investigate the radiographic features of the subaxial cervical spine after C1-C2 transarticular screw fixation for RA, we reviewed 28 cases of C1-C2 transarticular screw fixation for rheumatoid atlanto-axial subluxation. The sagittal alignment of C1-C2 and the subaxial cervical spine was measured and the factors that affect subaxial alignment were investigated. Subaxial alignment became less lordotic in the postoperative course. The C1-C2 fixation angle and subaxial alignment showed a negative linear correlation. However, no significant correlation was found between changes in the C1-C2 angle and changes in the subaxial alignment. Four patients had a postoperative kyphotic subaxial deformity. Neurologic deterioration recurred in 4 patients, because of the postoperative development of subaxial subluxation. Common radiographic changes included an increase in C1-C2 lordosis, constant inclination of C1, an anterior shift of C2, and a decrease in C2-C7 lordosis. Many factors, not only C1-C2 angle, are associated with subaxial sagittal alignment change after C1-C2 transarticular screw fixation.