Article

Correction of lumbosacral hyperlordosis in achondroplasia.

Department of Orthpaedic Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
Clinical Orthopaedics and Related Research (Impact Factor: 2.79). 10/2003; DOI: 10.1097/01.blo.0000081936.75404.a4
Source: PubMed

ABSTRACT Anterior bulging of the abdomen and posterior protrusion of the buttocks are externally visible deformities reflecting lumbosacral hyperlordosis. Imbalance in pelvic femoral muscles may account for this posture. Despite the clinical significance of hyperlordosis, its surgical treatment has not been well-described. In the current preliminary study, the authors compare two techniques used at the authors' institution for lower limb lengthening, one of which affects the correction of lumbosacral hyperlordosis. Ten patients had bilateral lower extremity lengthening procedures. Seven patients had bilateral tibial lengthening and three patients had combined femoral and tibial lengthening. Ring external fixators were used. Correction of hyperlordosis was assessed by comparing four radiographs with measurements in the sagittal plane obtained preoperatively with those at the latest followup. In the femoral lengthening group, the average preoperative lumbar lordosis angle was 18 degrees, the lumbosacral joint angle was 12 degrees, the sacral inclination angle was 58.3 degrees, and the sacrohorizontal angle was 31 degrees. The mean changes at the latest followup were: lumbar lordosis angle (+1 degree), lumbosacral joint angle (+0.3 degrees), sacral inclination angle (-19 degrees), and sacrohorizontal angle (-15 degrees). In the tibia lengthening group, all parameters were relatively unaltered at the last followup compared with their preoperative levels. Tibial lengthening had no effect on lumbosacral hyperlordosis. However, femoral lengthening resulted in an improved apparent lumbosacral hyperlordosis, although the lumbar lordosis angle was not changed significantly. The change in sacrum tilting provides a likely explanation for the improvement in cosmetic hyperlordosis observed in patients who have had femoral lengthening.

0 Bookmarks
 · 
163 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Achondroplasia and hypochondroplasia are the most common forms of short stature. The leading sign is the diminished body height. Most cases of achondroplasia can be detected by clinical examination. Hypochondroplasia is more often not diagnosed until preschool age.In achondroplasia many different orthopaedic problems can arise, which influence the ADL. Mainly pathologic alterations of the occipitocervical region or a stenosis of the medullary cavity should be expected. In the limbs a bow-leg deformity and hyperlaxity of the ligaments often can be seen, which in some cases restrict walking capacity. Even if many people of short stature contemplate a lengthening procedure, the correction of deformities is much more important. The CORA method should be used in planning any osteotomy.
    Der Orthopäde 02/2008; 37(1):40-8. · 0.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose of review: The spine is the location of the clinically most important manifestations of achondroplasia. These manifestations include foramen magnum stenosis, thoracolumbar kyphosis, lumbosacral hyperlordosis, and spinal stenosis. Recent findings: Decompression for foramen magnum stenosis in infants results in early improvements in respiratory function. However, complications include cerebrospinal fluid leaks, infection and recurrence. There are multiple surgical options for thoracolumbar kyphosis, and the pedicle anatomy has been further elucidated to increase the safety of spinal instrumentation in such patients. Spinal stenosis in pediatric patients with achondroplasia is associated with a significantly larger average percentage decrease in the transverse interpediculate distance from T12 to L5 and a significantly greater thoracolumbar kyphosis angle than in children with achondroplasia but no spinal stenosis. Decompression in pediatric patients carries a high risk of postlaminectomy kyphosis. When decompression is performed in older patients, results are not affected by increased body mass indices. Summary: The spinal manifestations of achondroplasia may require surgical treatment. Treatment must consider the anatomic variations unique to the achondroplastic spine.
    Current Orthopaedic Practice 07/2008; 19(4):376–382.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Lumbar stenosis is common in patients with achondroplasia because of narrowing of the neural canal. However, it is unclear what causes stenosis, narrowing of the central canal or foramina. We performed a morphometric analysis of the lumbar nerve roots and intervertebral foramen in 17 patients (170 nerve roots and foramina) with achondroplasia (eight symptomatic, nine asymptomatic) and compared the data with that from 20 (200 nerve roots and foramina) asymptomatic patients without achondroplasia presenting with low back pain without neurologic symptoms. The measurements were made on left and right parasagittal MRI scans of the lumbar spine. The foramen area and root area were reduced at all levels from L1 to L5 between the patients with achondroplasia (Groups I and II) and the nonachondroplasia group (Group III). The percentage of nerve root occupancy in the foramen between Group I and Group II as compared with the patients without achondroplasia was similar or lower. This implied the lumbar nerve root size in patients with achondroplasia was smaller than that of the normal population and thus there is no effective nerve root compression. Symptoms of lumbar stenosis in achondroplasia may be arising from the central canal secondary to degenerative disc disease rather than a true foraminal stenosis. LEVEL OF EVIDENCE: Level I, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.
    Clinical Orthopaedics and Related Research 05/2008; 466(4):907-13. · 2.79 Impact Factor