Surgical correction of lumbar kyphotic deformity: posterior reduction "eggshell" osteotomy.

OBJECT: Progressive kyphotic deformity of the lumbar or thoracolumbar spine may lead to back pain, cosmetic deformity, and risk of neurological compromise. The authors describe a series of patients in whom they performed a single-stage, posterior reduction ("eggshell") osteotomy procedure to improve sagittal contour by creating lordosis within a single vertebral body. METHODS: From 1995 to 1997 the authors performed 12 osteotomy procedures in 11 patients with thoracolumbar or lumbar kyphosis. Seven patients presented with iatrogenic deformity, three with deformity secondary to traumatic injury, and one patient with ankylosing spondylitis. Their mean age at time of surgery was 46.6 years (range 23-78 years). All patients suffered from back pain and were unable to stand upright, but in only one patient were neurological findings demonstrated. The mean preoperative deformity was -26 degrees (range -90 to 0 degrees). At 6-month follow-up examination the mean sagittal contour measured 17.5 degrees (range - 17 to 44 degrees), indicating that the mean surgical correction was 40.1 degrees (range 25 to 58 degrees). All patients reported decreased back pain at follow up, and none required narcotic analgesic medication. Complications included a dense paresis that developed immediately postoperatively in a patient who was found to have residual dural compression, which was corrected by emergency decompressive surgery. One elderly patient suffered a perioperative cerebrovascular accident, and three patients suffered neurapraxia with transient muscle weakness of the quadriceps. There was one case of a dural tear. There were no deaths, and prolonged intensive care stays were not required. CONCLUSIONS: Single-level posterior reduction osteotomy provides excellent sagittal correction of kyphotic deformity in the lumbar region, with a risk of cauda equina and root and plexus compromise due to the extensive neural exposure.

Isolated revision acetabuloplasty using a porous-coated cementless acetabular component without removal of a well-fixed femoral component. A 3- to 9-year follow-up study.

The results of isolated acetabular revision performed in 31 patients (32 hips) were monitored for between 3 and 9 years. All femoral components were well fixed and not removed or revised at the time of index surgery. There were 4 hips with little or no acetabular bony defect, 2 hips with pure segmental defects (type I), 10 hips with cavitary defects (type II), 15 with combined segmental cavitary defects (type III), and I with pelvic discontinuity (type IV). All revision acetabular implants were cementless, using a porous-coated hemispheric cup with or without bone-graft. There were four grade I reconstructions, 16 grade II reconstructions, and 12 grade III reconstructions. At final follow-up evaluation 94% of the cups were judged to be stable. Two hips required a second revision acetabuloplasty because of loss of fixation of the cup. The 2 repeat revisions were also done without removal of the femoral component. One acetabular component had evidence of rotational migration, which stabilized and remained nonprogressive. There were no cases of femoral component radiographic or clinical failure. The mean pre and postoperative hip scores were 44 and 83, respectively. The pre- and postoperative pain scores were 12 and 42, respectively. The findings of this study suggest that isolated acetabular revision, using a cementless porous-coated hemispheric cup, can be successfully performed without removing or revising a well-fixed femoral stem and not compromise the final outcome.

Surgical approaches for the correction of unstable thoracolumbar burst fractures: a retrospective analysis of treatment outcomes.

The authors retrospectively studied 49 nonparaplegic patients who sustained acute unstable thoracolumbar burst fractures. All patients underwent surgical treatment and were followed for an average of 27 months. All but one patient achieved solid radiographic fusion. Three treatment groups were studied: the first group of 16 patients underwent anterior decompression and fusion with instrumentation; the second group of 27 patients underwent posterior decompression and fusion; and the third group of six patients had combined anterior-posterior surgery. Prior to surgical intervention, these groups were compared and found to be similar in age, gender, level of injury, percentage of canal compromise, neurological function, and kyphosis. Patients treated with posterior surgery had a statistically significant diminution in operative time and blood loss and number of units transfused. There were no significant intergroup differences when considering postoperative kyphotic correction, neurological function, pain assessment, or the ability to return to work. Posterior surgery was found to be as effective as anterior or anterior-posterior surgery when treating unstable thoracolumbar burst fractures. Posterior surgery, however, takes the least time, causes the least blood loss, and is the least expensive of the three procedures.