Cervical Paraspinal Muscle Atrophy Rates Following Laminoplasty and Laminectomy with Fusion for Cervical Spondylotic Myelopathy

Imbalance of Muscles Around the Cervical Spine in Patients with Degenerative Cervical Spondylotic Kyphosis and Myelopathy

BACKGROUND

To measure the muscle strength around the cervical spine; clarify the relationships among muscles, cervical sagittal alignment, and cervical spondylotic myelopathy (CSM); and understand the process underlying loss of cervical lordosis.

METHODS

Sex, age, course of illness, and radiological data were obtained for patients with CSM and a control group of healthy individuals. C2-7 Cobb angles were measured in cervical radiographs, and the vertebral body areas (VBAs) and cross-sectional areas (CSAs) of the deep flexors, superficial flexors, deep extensors, and superficial extensors were measured from the C3/4 to C6/7 intervertebral levels in T2-weighted axial magnetic resonance images. The CSA/VBA ratio was compared among CSM patients with and without degenerative cervical kyphosis (DCK) and control group.

RESULTS

Patients with CSM, especially those with DCK, showed an imbalance of muscles around the cervical spine. The CSA/VBA ratios of superficial flexor/superficial extensor at the C3/4 level (P = 0.036), total flexors/total extensors at the C6/7 level (P = 0.006), total deep muscles/total superficial muscles at the C4/5 level (P = 0.004), and total deep muscles/total superficial muscles at the C6/7 level (P = 0.031) differed significantly among the 3 groups. The CSM with DCK group tended to show larger CSA/VBA ratios of flexors/extensors and superficial muscles/deep muscles.

CONCLUSIONS

The greater strength of the flexors relative to the extensors and the superficial muscles compared with the deep muscles plays a role in pathogenesis of CSM with DCK, indicating the importance of neck and shoulder muscle-strengthening exercises in patients showing CSM with DCK.

Comparison of time-dependent resistance isometric exercise and active range of motion exercise in alleviating the sensitization of postoperative axial pain after cervical laminoplasty

BACKGROUND

Postoperative axial pain (PAP) is a significant complication after cervical laminoplasty.

OBJECTIVE

To investigate pain sensitization in PAP patients and effects of time-dependent resistance isometric exercise compared to active range-of-motion exercise on PAP.

STUDY DESIGN

Retrospective cohort analysis.

METHODS

211 patients undergoing postoperative 12-week exercises were evaluated for pressure pain threshold (PPT), temporal summation (TS) and both cross-sectional area and fatty infiltration of paraspinal muscles preoperatively and 3 months postoperatively. There patients underwent Numeric rating pain scale (NRS) and neck disability index (NDI) 3 and 6 months postoperatively.

RESULTS

At postoperative 3-month assessments, fewer patients undergoing isometric exercise showed PAP compared to range-of-motion exercise group (14/98 vs. 34/113; P = 0.006), and pain-related assessments in the former were lower than the latter (NRS at rest: 0.3 ± 0.8 vs. 0.7 ± 1.4, P = 0.014; NRS with movements: 0.4 ± 1.0 vs. 1.0 ± 1.7, P = 0.015; NDI: 2.4 ± 6.3 vs. 6.7 ± 10.9, P = 0.002). Postoperative cross-sectional area was smaller in isometric exercise group (603.5 ± 190.2) than in range-of-motion exercise group (678.7 ± 215.5) (P = 0.033), and the former showed higher local-area PPT and lower TS than the latter (PPT: 3.9 ± 1.8 vs. 3.1 ± 1.6, P = 0.002; TS: 1.8 ± 0.9 vs. 2.2 ± 1.0, P = 0.003). PAP patients showed lower local-area PPT and greater TS than those without PAP in both isometric (PPT: 2.8 ± 0.7 vs. 4.0 ± 1.9, P = 0.019; TS: 2.4 ± 0.6 vs. 1.7 ± 0.9, P = 0.011) and range-of-motion (PPT: 2.2 ± 0.9 vs. 3.6 ± 1.7, P < 0.001; TS: 2.8 ± 0.8 vs. 1.9 ± 0.9, P < 0.001) exercise groups.

CONCLUSIONS

Both peripheral and central sensitization are involved in PAP. Time-dependent isometric exercise has more positive effects on PAP than range-of-motion exercise because of its advantages in improving pain sensitization.

The Role of Cervical Muscles Morphology in the Surgical Treatment of Degenerative Disc Disease: Clinical Correlations Based on Magnetic Resonance Imaging Studies

Cervical spine musculature still remains a less studied component of the cervical spine anatomical compartments, although it plays a significant role in the mobility of the head and the preservation of cervical spine alignment. The goal of this study was to extract any significant information from the literature regarding the role of cervical spine muscles morphology in the outcome of surgically treated patients for degenerative disc disease (DDD) based on preoperative magnetic resonance imaging (MRI) studies. Eleven clinical case series were found, from which four were prospective and seven were retrospective. Six studies were concentrated on anterior approaches and five studies on posterior approaches in the cervical spine. In posterior approaches aiming at the preservation of muscles attachments and overall less surgical manipulations, results on cervical lordosis, axial pain and patient’s functionality were found superior to traditional laminectomies. The study of cross-sectional areas (CSAs) of deep paraspinal muscles in the cervical spine could add significant information for the spine surgeon such as the prediction of adjacent level disease (ALD), fusion failure, axial pain persistence, postoperative cervical alignment and patient’s postoperative functionality. It seems that MRI studies focusing on muscle layers of the cervical spine could add significant information for the spinal surgeon regarding the final surgical outcome in terms of pain and function expression. Larger multicenter clinical studies are a necessity in defining the role of the muscle component of the cervical spine in the surgical treatment of DDD.

Association between Changes in Sagittal X-ray Measurements and Neck Extensor Muscle Atrophy after Cervical Laminoplasty

BACKGROUND

To investigate the association between neck extensor muscles (NEM) atrophy and changes in the sagittal cervical X-ray measurements after cervical laminoplasty.

BASIC PROCEDURES

This retrospective analysis was conducted on 64 patients who underwent cervical laminoplasty from March 2016 to March 2019. The preoperative and postoperative sagittal cervical X-ray images were measured, including the C2-C7 cobb angle, the C2-7 sagittal vertical axis (SVA), and the angle between the plane of the upper endplate of T1 vertebra and the horizontal plane (T1 slope). The preoperative and postoperative steatosis ratios of the NEM were measured using magnetic resonance images.

MAIN FINDINGS

There were significant differences between the preoperative and postoperative measurements of the C2-7 cobb angle, the C2-7 SVA, and the T1 slope (P<0.05). The preoperative and postoperative steatosis ratios of each intervertebral level of the NEM also differed significantly (P<0.05). The muscle atrophy ratio at C3/4 was positively correlated with the change in the C2-7 SVA (R=0.646, P<0.001) and negatively correlated with the change in the C2-7 cobb angle (R=-0.445, P<0.001). The muscle atrophy ratio at C7/T1 was positively correlated with the T1 slope (R=0.446, P<0.001).

CONCLUSIONS

Muscle atrophy was more severe at the attachment points of the NEM (C3/4, C7T1). There was a significant association between the muscle atrophy ratio and the changes in sagittal cervical X-ray measurements.

Change in the dimensions of the lumbar area muscles after surgery: MRI analysis

OBJECTIVE:

This study aims to assess the change in the dimensions of the lumbar muscles in patients with chronic lower back pain using Magnetic Resonance Imaging (MRI) and to determine pre/post effects of surgery.

METHODS:

We enrolled 28 individuals (13F/15M; age: 45.39±11.56 years) whose L2–S1 muscle measurements were obtained using MRI, before and at follow-up 6–12 months after surgery. The control group comprising 37 individuals (18F/19M; age: 34.41±10.72 years) who had no lumbar pathology but for whom retrospective archive images were available. In the axial MRI analysis, the cross-sections of m.multifidus, mm.erector spinae and m.psoas major on both sides were measured with the ‘closed polygon’ technique.

RESULTS:

The L2–3 and L4–5 levels of the m.multifidus on the right side, the L2–3, L4–5 and L5–S1 levels of the m.multifidus and the L5–S1 levels of the mm. erector spinae on the left side cross-sectional areas were significantly lower than the control group (p<0.05). The right-side m.multifidus and the left-side mm.erector spinae sectional areas were significantly lower than the pre-surgery values at the L5–S1 levels (p<0.05).

CONCLUSION:

This study demonstrated that chronic lower back pain causes atrophy in the lumbar muscles and established the existence and continuity of atrophy after surgery.

Surgery of degenerative thoracic spinal stenosis-long-term outcome with quality-of-life after posterior decompression via an uni- or bilateral approach

BACKGROUND

The rate of degenerative thoracic spinal stenosis (TSS) as underlying pathology for myelopathy is not precisely known, and larger case series are only available for the Asian region. We present one of the largest European series to evaluate rate and clinical outcome after dorsal decompression via a uni- or bilateral approach.

METHOD

We investigated patients' characteristics, imaging/surgical parameters, and outcomes with quality-of-life (QOL) in all patients who underwent surgical treatment for TSS between 2013 and 2018 in a university neurosurgical clinic.

RESULTS

From 645 patients with surgery for degenerative spondylotic myelopathy within 6 years, 28 patients (4.3%) suffered from TSS. Median age was 70.4 years with a slight predominance of the female sex (m:f = 1:1.3). The most frequent symptoms (mean duration 7.6 months) were ataxia (61%) and sensory changes (50%). The stenoses (median Naganawa score 3) mostly resulted from a combined osseous/ligamentous hypertrophy and disc prolapse, the majority located below Th8 (75%). Nineteen patients with lateralized compression underwent bilateral decompression via a unilateral approach (fenestration/hemilaminectomy with "undercutting" procedure), and 9 patients with circular pathology underwent bilateral-approached decompression (laminectomy). There were no significant differences of patients' characteristics, blood loss, operation time, and in-patient stay between both surgical groups. Independent from the mode of surgery, the spinal canal was significantly (p < 0.001) widened (median Naganawa score 0), and pain (p = 0.04), myelopathy (mJOA score p = 0.01), and QOL (Oswestry Disability Index, p = 0.03; SF-36-MCS, p = 0.01) were significantly improved at long-term follow-up (mean 35.1 months).

CONCLUSIONS

Non-tumorous myelopathy is caused in about 4% of patients by TSS and can be effectively treated by surgical decompression via both a uni- or bilateral approach.