Prediction of incomplete decompression after cervical laminoplasty on magnetic resonance imaging: The modified K-line.

OBJECTIVES: The original K-line was developed on plain radiograph to predict incomplete indirect decompression for the patients with ossification of the posterior longitudinal ligament. The current study modified the K-line on magnetic resonance imaging (MRI) to determine risk factors for incomplete decompression after laminoplasty and to provide a guide for predicting incomplete decompression after laminoplasty and making decisions regarding the surgical approach in patients with cervical spondylotic myelopathy (CSM). PATIENTS AND METHODS: A retrospective review of 47 patients with CSM after laminoplasty was conducted. The modified K-line was defined as a line connecting both anterior points of the spinal cord at the level of the inferior vertebrae endplates of C2 and C7 on sagittal T1-weighted MR image. Quantitative analysis of the interval between the maximal anterior compression factor and the modified K-line (IAK) was performed to investigate the efficiency and practicality of this modified K-line. Data analysis involved logistic regression and Spearman rank correlation coefficient. RESULTS: Thirteen patients (27.7%) had postoperative residual anterior compression of the spinal cord (ACS). Univariate logistic regression with backward stepwise procedure showed that only IAK (odds ratio: 0.301; 95% confidence interval: 0.134-0.673, P=0.003) was a significant risk factor for the occurrence of postoperative ACS. Incidence of ACS was 80% in patients with an IAK of less than 1.5mm and 96.2% in those whose IAK is 0mm. CONCLUSION: The modified k-line can provide a guide for predicting poor clinical outcome after laminoplasty and making decisions regarding the surgical approach in patients with CSM.

Predictors for Surgical Outcome of Laminoplasty for Cervical Spondylotic Myelopathy.

BACKGROUND: There were no precise researches showing which parameters with regard to degree of cervical stenosis and sagittal cervical alignment are the most crucial for surgical outcomes after laminoplasty for cervical spondylotic myelopathy (CSM). The objectives of this study were to investigate to what extent the preoperative parameters may have a direct influence on postoperative neurologic recovery, and to determine the crucial determinants of prognosis. METHODS: A retrospective review of 83 patients with CSM after laminoplasty was conducted. Magnetic resonance imaging parameters evaluation included presence/absence of signal change on T1 and T2 and anatomic measurements, including cervical canal compromise and cervical alignment. Data analysis involved logistic regressions and Spearman rank correlation coefficients. Receiver operator characteristic (ROC) curves were computed to evaluate the contribution of the original model. RESULTS: Univariate logistic regression showed that age (odds ratio = 0.822; 95% confidence interval, 0.729-0.927; P = 0.001), baseline Japanese Orthopedic Association (JOA) score (odds ratio = 1.700; 95% confidence interval, 1.158-2.496; P = 0.007), cervical curvature index (Ishihara) score (CCI) (odds ratio = 1.123; 95% confidence interval, 1.030-1.225; P = 0.008), maximum canal compromise (MCC) (odds ratio = 0.940; 95% confidence interval, 0.885-0.998; P = 0.041), and signal intensity (odds ratio = 0.139; 95% confidence interval, 0.033-0.580; P = 0.007) were independent prognostic indicators after laminoplasty. A ROC curve was computed based on the probability of the five predictors, with an area under the curve of 0.929 ± 0.028. CONCLUSIONS: Age and baseline JOA scores were crucial clinical predictors of outcome after laminoplasty for patients with CSM. Regarding the predictive value, CCI, MCC, and patterns of signal intensity changes on T1-/T2-weighted images were crucial determinants of prognosis of neurologic outcome.

Prediction of prognosis in patients with cervical spinal cord injury without radiologic evidence of trauma using MRI.

The purpose of this study was to investigate whether pre- to postoperative changes of increased signal intensity (ISI) of the spinal cord as seen on T2-weighted magnetic resonance imaging (MRI) reflect the surgical outcome in patients with cervical spinal cord injury without radiologic evidence of trauma (SCIWORET). In this study, 54 patients with SCIWORET who underwent expansive laminoplasty were retrospectively analyzed. All patients underwent MRI at an average of 1.9 days (range, 1-5 days) after injury and 7.9 days (range, 6-10 days) postoperatively. The pre- and postoperative range and degree of ISI were measured on computer software using the same sagittal view on T2-weighted MRI. Then, the post-preoperative ratio of range and degree of ISI were calculated. Pre- and postoperative neurologic evaluations were performed according to the criteria proposed by the Japanese Orthopedic Association (JOA). A significant negative correlation existed between the ratio of range of ISI and the recovery rate (r=-0.504, P<.01). The ratio of degree of ISI negatively correlated with the recovery rate, but this was not statistically significant. Patients were divided into 2 groups according to the ratio of degree of ISI: group A included patients with a ratio of degree of ISI of ≤1 (n=24) and group B included patients with a ratio of degree of ISI of >1 (n=30). Patients' mean recovery rate was 65.0%±6.3% in group A and 52.4%±7.4% in group B. A significant difference was found between the 2 groups (P<.001, Student's t test) when comparing recovery rate. The pre- to postoperative changes of the range and degree of ISI significantly reflected prognosis for surgical outcome in patients with SCIWORET.

[Repair of the soft tissue defects at legs with free tissue flap anastomosed with descendant branch of lateral femoral circumflex artery].

OBJECTIVE: To investigate the therapeutic effect of free tissue flap anastomosed with reverse descendant branch of lateral femoral circumflex artery for severe soft tissue defect at leg. METHODS: The severe soft tissue defect at leg, without any vessels for anastomosis of free tissue flap, was reconstructed with free tissue flap, which was anastomosed with proximal end of descendant branch of lateral femoral circumflex artery and great saphenous vein. From Oct. 2004 to Dec. 2009, 36 cases were treated with 15 cases of latissimus dorsi musculocutaneous flaps, 12 cases of anterolateral femoral flaps, and 9 cases of thoracoumbilicus flaps. RESULTS: All the 36 free flaps survived completely. The patients were followed up for 6 months to 2.5 years with good cosmetic results. CONCLUSIONS: It is effective and practical to repair the severe soft tissue defects at legs with the reverse descendant branch of lateral femoral circumflex artery to carry the free flaps.

[Repair of defects at the end of fingers with island flaps pedicled with digital artery].

OBJECTIVE: To investigate the therapeutic effect of island flaps pedicled with digital artery for the defects at the end of fingers. METHODS: 63 cases with 72 soft tissue defects at the end of fingers were treated with the island flaps. The flap size ranged from 8 mm x 11 mm to 21 mm x 27 mm. RESULTS: All the flaps survived completely. The follow-up period ranged from 4 to 19 months. The functional and cosmetic results were satisfactory. The two-point discrimination was 7 to approximately 9 mm. The TAM functional examination showed excellent in 59 fingers, good in 11 fingers and common in 2 fingers. CONCLUSIONS: The technique with island flap is simple and reliable for the defects at the end of fingers.