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Fibrous dysplasia of the anterior cranial base involves the bony orbit and optic canal. Although fibrous dysplasia is benign, it may produce a mass effect along the course of the optic nerve, inducing visual disturbances. Optic canal decompression in patients without clinical signs of optic neuropathy is controversial. We describe five patients with extensive fibrous dysplasia of the anterior cranial base involving the orbit and optic canal. These patients underwent transcranial optic canal decompression before signs of severe visual loss during correction of dystopias and craniofacial deformity induced by fibrous dysplasia. Cranial orbital reconstruction was performed by means of split rib and cranial bone grafts. Postoperative follow-up did not reveal disturbances in visual function, extraocular motility, or evidence of cerebrospinal fluid fistulas. This suggests that early, radical resection of orbital fibrous dysplasia with optic canal decompression may be effective in preventing visual loss with minimal risk of other neurological sequelae. Subsequent orbital reconstruction involving split-thickness rib and cranial bone grafting yields satisfactory cosmetic results.

Far lateral and related lumbar disc herniations that feature cephalad migration of fragments away from their disc space of origin can no longer be considered rare. Contemporary imaging techniques now reveal these herniations commonly. The anatomy of the foraminal and extraforaminal (far lateral) regions has been described and should be familiar to all spine surgeons. Each surgeon should be capable of recognizing the distinct entity of the far lateral disc herniation and should be adept at surgery in this region by one of several available techniques. I prefer a posterior, direct microsurgical approach through a midline incision featuring foraminotomy because of its ease, exposure, adaptability, and efficacy.

Forty-eight patients had 50 extraforaminal disk herniations (EFDHs) demonstrated on CT and/or MR by (1) presence of disk density or disk signal material lateral to the neural foramen, (2) displacement or obliteration of paravertebral fat, and (3) nerve root or ganglion compression or displacement. Forty-one of 50 EFDHs had a coexisting intraforaminal component; nine of 50 had an isolated far lateral herniated nucleus pulposus. EFDHs typically occurred in the absence of a coexisting intraspinal disk herniation. Migratory fragments were seen in 50% of all cases and were at or cephalad to the interspace of origin in all cases. Forty-six percent of EFDHs were at L2-L3 or L3-L4, although the most commonly affected level was L4-L5 (38%). EFDHs, which were often overlooked (15/50 scans reviewed), are an important preventable cause of failed intraspinal diskectomy. EFDHs can be readily identified on both CT and MR if appropriate scans are obtained from L2 through S1 and if the neural foramina and paravertebral spaces are carefully examined.

In an attempt to determine whether certain physical characteristics discriminated between people with and without herniated intervertebral lumbar discs, volunteers (N = 40) who were diagnosed as having a herniated lumbar disc were compared to control subjects (N = 40) who had been randomly selected and matched by age and sex. All subjects completed a questionnaire to determine the history of their back injury and a description of their exercise behavior patterns. Body composition was estimated by hydrostatic weighing. Maximum oxygen consumption was predicted using the Astrand-Ryhming nomogram. Strength scores were determined from a battery of cable tensiometer tests. Dependent variables were analyzed using a multiple analysis of variance (MANOVA). Using discriminant analysis, as a post hoc test, predicted maximum oxygen consumption was shown to account for the difference between the groups (P less than .002). The control subjects' values were higher than the patients' values. Subjects' exercise history indicated no differences between the groups relative to the time period preceding the onset of injury (P greater than .05). The exercise activity of patients was significantly reduced after injury (P less than .001). An average of 87 days elapsed between the onset of injury to the date of fitness testing.