Microsurgical posterior foraminotomy with laminoplasty for cervical spondylotic radiculomyelopathy including cervical spondylotic amyotrophy

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The authors retrospectively investigated the surgical outcomes and radiographically documented changes after microsurgical posterior foraminotomy with en bloc laminoplasty in patients with cervical spondylotic radiculo-myelopathy (CSRM), including cervical spondylotic amyotrophy (CSA), during a period greater than 2 years.


Thirty-four consecutive patients (24 men and 10 women) were included in this study. Twenty patients had preoperative radicular pain, and CSA was diagnosed in 14 patients. The mean age at the time of surgery was 61 years (range 43–77 years). The follow-up period ranged from 2 to 6.5 years (mean 3.4 years). Foraminotomy was performed at 49 sites. Neurological improvement was evaluated using the Japanese Orthopaedic Association (JOA) scoring system; radicular pain and deltoid muscle strength were also evaluated clinically. Cervical lordosis, flexion–extension angles, range of motion (ROM), and the angulation and the extent of vertebral slippage at the affected nerve root levels were measured preoperatively and at last follow-up examination.

The mean rate of JOA score improvement was 67.2% (range 22.2–100%). In all 20 patients, preoperative radicular pain completely resolved after surgery. In all 14 patients with CSA, deltoid muscle strength improved; in approximately 80% of these patients, there was either no muscle weakness or only slight weakness. The flexion angles and ROM significantly decreased at the time of the last follow-up examination (p = 0.0402 and 0.0196, respectively). No other items changed significantly.


The aforementioned surgical procedure was safely completed and the surgical outcomes were satisfactory for CSRM including CSA. The instability (the angulation and the vertebral slippage) did not significantly change after surgery. This procedure yielded outstanding results and should be considered an option for cervical laminoplasty in the future.

Abbreviations used in this paper:CSA = cervical spondylotic amyotrophy; CSRM = cervical spondylotic radiculomyelopathy; CT = computed tomography; JOA = Japanese Orthopaedic Association; MMT = manual muscle test; MR = magnetic resonance; ROM = range of motion; RSD = reflex sympathetic dystrophy; VB = vertebral body.

Article Information

Address reprint requests to: Kunihiko Sasai, M.D., Ph.D., Department of Orthopedic Surgery, Kansai Medical University, 2-3-1 Shinmachi, Hirakata City, Osaka 573-1191, Japan. email: sasaik@hirakata.kmu.ac.jp.

© AANS, except where prohibited by US copyright law.



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    Drawings representing preoperative and follow-up radiographic measurements on lateral radiographs. A: Cervical lordosis was measured as the angle formed by the two lines drawn on the posterior C2–7 VB margins. B: The angle formed by the two lines drawn between the inferior margin of the upper VB and the superior margin of the lower VB was measured at the level where the foraminotomy was performed. C: The length of the posterior margin between the upper and the lower VBs was also measured at the foraminotomy-treated level. The difference between maximal flexion and maximal extension was calculated as the angulation and the extent of vertebral slippage.

  • View in gallery

    Chart showing the changes of the deltoid muscle strength in 14 patients with CSA. Black circles indicate preoperative status and white circles the result obtained at the last follow up. In all patients, the deltoid muscle strength improved postoperatively. There was a complete or marked reduction of strength in 11 patients and 50% reduction of strength in three patients preoperatively, whereas after surgery, there was a 50% reduction in three patients (21%) and no or slight reduction of strength in 11 patients (79%).

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    Representative radiographs obtained in a 73-year-old woman with CSA. Right-sided microsurgical foraminotomy at C-5 root and C3–7 en bloc laminoplasty were performed. A–C: Preoperative lateral radiographs. Cervical lordosis, the flexion angle, the extension angle, ROM, and the angulation and the extent of slippage at C4–5 were 28°, 42°, 12°, 54°, 13°, and 1 mm, respectively. D–F: Lateral radiographs obtained 5.1 years postoperatively. Cervical lordosis, the flexion angle, the extension angle, ROM, and the angulation and the extent of vertebral slippage at C4–5 were 29°, 29°, 15°, 44°, 8°, and 1 mm, respectively.

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    Representative MR and CT myelography images obtained in a 55-year-old man with CSA. A: Preoperative sagittal T2-weighted MR image revealing multiple stenoses. B: Preoperative CT myelograms showing compression ofboth right anterior horns at the paramedian lesion at the C3–4 and C4–5 levels and right C-5 and C-6 anterior root compression caused by the superior facet at the preforaminal lesion in the C4–5 and C5–6 levels. Electromyography demonstrated chronic partial denervation potentials of the right-sided deltoid, biceps, extensor carpi radialis, and the paraspinal muscles. We performed microsurgical right-sided foraminotomy at the C-5 and C-6 roots and C3–7 en bloc laminoplasty. Under the microscope, both the C-5 and C-6 nerve roots were sufficiently decompressed after removal of only approximately 2 to 3 mm of the superior facet, even if the spur of both facet joints projected. C: Axial CT scans acquired 6 months postoperatively. Black arrows indicate area where foraminotomy was performed. The strength of the deltoid muscle, which preoperatively was Grade 0–1/5 (complete or marked reduction in strength), was shown to be Grade 4–5/5 (no or slight reduction in strength) 4.3 years following surgery.



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