Partitioning and diversity of nuclear and organelle markers in native and introduced populations of Epipactis helleborine (Orchidaceae).

Variability of allozymes (1170 individuals, 47 populations) and chloroplast DNA (692 individuals, 29 populations) was examined in native European and introduced North American populations of Epipactis helleborine (Orchidaceae). At the species level, the percentage of allozyme loci that were polymorphic (P(99)) was 67%, with a mean of 2.11 alleles (A) per locus, and an expected heterozygosity (H(exp)) of 0.294. At the population level, mean P(99) = 56%, mean A = 1.81, and mean H(exp) = 0.231. Although field observations suggest that self-pollination occurs frequently, populations had a genetic structure consistent with Hardy-Weinberg expectations and random mating (mean F(IS) = 0.002). There was significant deviation from panmixia associated with population differentiation (mean F(ST) = 0.206). The distribution of two chloroplast haplotypes showed that 15 of the 29 populations were polymorphic. Using both nuclear and organelle F(ST) estimates, a pollen to seed flow ratio of 1.43 : 1 was calculated. This is very low compared with published estimates for other plant groups, consistent with the high dispersability of orchid seeds. Finally, there was no evidence for a genetic bottleneck associated with the introduction of E. helleborine to North America.

Bending of the Cotrel-Dubousset instrumentation after direct trauma: a case report.

STUDY DESIGN: Case report. OBJECTIVES: To describe a fracture through the fusion mass of a spine that had been corrected previously with Cotrel-Dubousset rods. These rods had failed in bending after direct trauma. SUMMARY OF BACKGROUND DATA: Nine years after successful treatment of scoliosis with Cotrel-Dubousset instrumentation, the patient was in a motor vehicle accident and sustained a hyperextension spine injury with complete L1-L2 paraplegia and disruption of the fusion mass. The Cotrel-Dubousset instrumentation rods, which failed in bending, could not be corrected in situ, and the angulated segments had to be resected. The spine then became extremely unstable, and the patient consulted the authors for definitive stabilization. RESULTS: The spine was stabilized by attaching the proximal and distal retained Cotrel-Dubousset instrumentation to supplemental rods in a "domino" fashion. Crosslinks were added to improve the torsional stability. Intraoperatively, the fracture was well reduced, and the fixation was stable. A posterolateral fusion was performed with allogenic bone graft. CONCLUSION: Bent Cotrel-Dubousset instrumentation rods are still very strong and may not correct in situ.- If resection is required, the retained portions of Cotrel-Dubousset instrumentation can serve as attachments to restore stable fixation a "domino"technique.

The omnivorous Tyrolean Iceman: colon contents (meat, cereals, pollen, moss and whipworm) and stable isotope analyses.

The contents of the colon of the Tyrolean Iceman who lived ca. 5300 years ago include muscle fibres, cereal remains, a diversity of pollen, and most notably that of the hop hornbeam (Ostrya carpinifolia) retaining cellular contents, as well as a moss leaf (Neckera complanata) and eggs of the parasitic whipworm (Trichuris trichiura). Based almost solely on stable isotope analyses and ignoring the work on the colon contents, two recently published papers on the Iceman's diet draw ill-founded conclusions about vegetarianism and even veganism. Neither the pollen nor the moss is likely to have been deliberately consumed as food by the Iceman. All the available evidence concerning the Iceman's broad-based diet is reviewed and the significance of the colon contents for matters other than assessment of food intake is outlined.

Efficacy and cost considerations of intraoperative autologous transfusion in spinal fusion for idiopathic scoliosis with predeposited blood.

STUDY DESIGN: One hundred five patients with adolescent idiopathic scoliosis who underwent posterior spinal instrumentation and fusion with predeposited autologous blood, with or without intraoperative autologous transfusion, were reviewed. OBJECTIVE: To determine the benefit/nonbenefit of intraoperative autologous transfusion in diminishing the need for homologous blood and influencing post-operative hematocrit values in healthy adolescents undergoing spinal fusion for scoliosis. SUMMARY OF BACKGROUND DATA: A steady increase in the use of intraoperative autologous transfusion in recent years has occurred without guidelines regarding which procedures and patient populations would be best served. Previous studies have failed to determine the cost effectiveness and actual reduction in homologous blood exposure attributable to intraoperative autologous transfusion in adolescents who have undergone preoperative phlebotomy. METHODS: Fifty-five adolescents (intraoperative autologous transfusion group) who underwent posterior instrumentation and fusion for idiopathic scoliosis with the use of an intraoperative autologous transfusion device were compared to 50 patients (control group) who underwent the same procedure without the intraoperative autologous transfusion device. RESULTS: The average percent salvage of red blood cells by the intraoperative autologous transfusion device was 35%. The control group utilized significantly more of the predonated autologous blood than the intraoperative autologous transfusion group (1.34 units/case vs. 1.78 units/case, P < 0.05). Homologous blood usage was the same in both groups. Two patients in the intraoperative autologous transfusion group required nondirected homologous blood (total of four units), compared to three patients in the control group (total of four units) (P = 0.048). Using multiple regression analysis, the total number of transfusions was significantly correlated with the estimated blood loss and the duration of surgery in both groups. Postoperative hematocrit levels were slightly higher in the control group, but there was not a significant difference. CONCLUSIONS: The addition of intraoperative autologous transfusion to a preoperative phlebotomy program had no benefit on homologous blood exposure or post-operative hematocrit changes in this population. Blood requirements for this procedure can be met less expensively and more reliably by merely donating one's own blood.

An in-vitro biomechanical comparison of the Orosco and AO locking plates for anterior cervical spine fixation.

The Orosco anterior cervical spine plate (H-plate) and the Morscher AO cervical locking plate (CSLP) were studied to determine their comparative in vitro mechanical properties in flexion. Human cadaver cervical spines were tested nondestructively in flexion as intact, destabilized, and stabilized specimens with both implants. Stabilized specimens were also subjected to a large angular displacement in an attempt to induce implant failure. Differences between intact, destabilized, and stabilized specimens were significant for both the CSLP and H-plate groups in flexion testing (p < 0.05). Large angular displacement testing resulted in plate/screw displacement with the H-plate but not with the CSLP. Small angular displacements in flexion was tolerated well by both implants, but only the CSLP maintained stability with large angular displacements.

Results of operative treatment of idiopathic scoliosis in adults.

We compared the results in eighty-one patients (average age, fifty-six years; range, forty-three to eighty-three years) who had had operative treatment of idiopathic scoliosis with those in thirty patients (average age, fifty-eight years; range, forty-five to seventy years) who had declined operative treatment. Seventy-six individuals (average age, forty-eight years; range, thirty-five to seventy-four years) who did not have scoliosis served as a control group. The average duration of follow-up was five years (range, two to seventeen years). The population base consisted of 454 patients who were seen between 1970 and 1985. The treated patients were drawn from a group of 160 patients for whom an operation had been recommended; 110 patients agreed to the operation and fifty refused. The remaining 294 patients had curves of insufficient severity to warrant concern about progression, had symptoms unrelated to the scoliosis, or had curves that did not necessitate any intervention. The functional status since the operation (for the treated patients), since recommendation of the operation (for the untreated patients), or within the last ten years (for the control group) was evaluated with a comprehensive questionnaire designed to elicit details regarding pain, fatigue, and any disability in the performance of twenty-six activities of daily living. At the most recent follow-up examination, the treated patients reported a significantly greater decrease in pain and fatigue and significantly more improvement in self-image and in the ability to perform physical, functional, and positional tasks than did the untreated patients (p = 0.0001).

Effect of operative position on sagittal alignment of the lumbar spine.

A variety of techniques and frames are used for positioning patients during posterior lumbar spinal instrumentation and fusion. Little information is available on the relationship of lumbar lordosis and the various positioning options, so it was felt that further investigation was warranted. Ten volunteers with no history of back pain were positioned and radiographed in the standing position followed by four lateral radiographs with the patient positioned on chest rolls, Andrew's frame, the Hasting's frame, and a four-poster spinal frame. Total lumbar lordosis from L1 to S1 as well as intervertebral body angles at each of the lumbar interspaces using standardized techniques were computed. No significant difference was found in lumbar lordosis between the standing and chest roll position. However, there was approximately a 50% reduction in lumbar lordosis when using the Hasting's, Andrew's, and four-poster frame as compared to the standing and chest roll configuration. The clinical implications are discussed.

Interspace distraction and graft subsidence after anterior lumbar fusion with femoral strut allograft.

The authors performed a retrospective review of 32 patients who had undergone a single-level anterior lumbar fusion with femoral strut allograft as an isolated procedure. The goal of the study was to use clinical radiographs to measure interspace distraction, graft subsidence, interspace collapse, the nature of allograft incorporation, and to correlate these results with successful arthrodesis. Results were categorized according to plain radiographic appearance and flexion/extension stability. Sixty-six percent of the group exhibited radiographic union with flexion/extension stability. Twenty-two percent exhibited stability on the flexion-extension analysis but less than complete arthrodesis was present. Twelve percent exhibited radiographic non-union and flexion-extension instability. Interspace distraction of 11 mm was obtained initially with a follow-up distraction of 5.5 mm. Graft subsidence was noted posteriorly in 27 patients with an average subsidence of 4 mm. The authors' conclusions were: 1) Interspace distraction can be achieved with anterior lumbar fusion if appropriate interbody grafts are used. 2) Despite a solid arthrodesis rate of only 66%, "functional arthrodesis" was achieved in 88%. In a retrospective review of patients who underwent anterior lumbar fusion with femoral strut allograft, interspace distraction, graft subsidence, and incorporation and arthrodesis status were measured. A solid arthrodesis was achieved in 66% of the patients, and functional arthrodesis in another 22%. Interspace distraction was maintained in 59% of cases.

Cervical spine locking plate: in vitro biomechanical testing.

The AO cervical spine locking plate (CSLP) for anterior subaxial fixation was recently received increasing clinical acclaim, yet to date the in vitro mechanical properties of this implant have not been reported. To determine the in vitro biomechanical properties of this device, five fresh human cadaver cervical spines were subjected to nondestructive testing in flexion and torsion in three stages: stage 1: intact spine; stage 2: destabilized spine; stage 3: destabilized spine with CSLP. Stage 3 specimens were also subjected to large angular displacement testing to assess the integrity of the fixation. In flexion, mean spinous process displacement was 1.21 mm for stage 1, 3.19 mm for stage 2, and 1.37 mm, for stage 3. Mean torsional stiffness was 2.86 Nm/degree in stage 1, 1.82Nm/degree in stage 2, and 2.20Nm/degree in stage 3. Large angular displacement testing in stage 3 resulted in screw loosening from the bone in two specimens; no screw plate loosening occurred. In our severely destabilized in vitro model, the CSLP restored flexion stability but not rotational stability. This suggests that supplemented bracing or fixation may be required to restore torsional stability.

Hypotensive anesthesia for scoliosis surgery in Jehovah's Witnesses.

Hypotensive anesthesia has been advocated in spinal surgery for the purpose of diminishing operative blood loss. This study evaluated its effectiveness in 12 Jehovah's Witnesses undergoing Harrington instrumentation and fusion who refused transfusion. Previous series from this institute did not use deliberate hypotension because of routinely low blood loss. Compared with matched controls operated on under normotensive anesthesia, the Jehovah's Witness patients had lower absolute blood loss but also shorter operative time. Applied linear-regression analysis demonstrated that the diminished blood loss was associated with shorter operative time (P = 0.0002) rather than lower blood pressure. The majority of blood losses in spinal instrumentation with fusion occurs with decortication. This rapid bleeding occurs at venous pressures which are unaffected by arterial blood pressure manipulation. The authors conclude that spinal surgery is possible in Jehovah's Witnesses without transfusion and that operative technique is the single most important determinant of blood loss.

The vegetational history of Glen Diomhan, North Arran, site of endemic whitebeams, Sorbus arranensis Hedl. and S. pseudofennica E.F. Warb.

A detailed pollen analysis was undertaken of sediment from a site in Glen Catacol on the Isle of Arran, Scotland, close to Glen Diomhan National Nature Reserve which has a large though possibly declining population of the endemic whitebeams, Sorbus arranensis Hedl. and S. pseudofennica E.F. Warb. Blanket peat formation began before 7000 years BP. The results provide evidence that while parts of the glen saw the development and subsequent decline of birch, oak, hazel and alder woodland a large proportion of the surrounding vegetation has remained open throughout the Flandrian with grass-heath similar to that which occurs over much of the glen in the present day.

Harrington instrumentation and arthrodesis for idiopathic scoliosis. A twenty-one-year follow-up.

A questionnaire was sent to 206 consecutive patients who were operated on for idiopathic scoliosis by Dr. Paul R. Harrington between 1961 and 1963. Eighty-three per cent of the patients responded to the questionnaire, which consisted of five sections: demographic data, activities of daily living, back symptoms (pain and fatigue), a history of personal and family health, and a personal assessment of the back. One hundred and eleven patients also sent recent radiographs. A control group, comprising 100 individuals who did not have scoliosis and had been matched for age and sex, was given the same questionnaire. The study group had more pain in the interscapular and thoracolumbar regions compared with the control group, but there was no difference with respect to pain in the lumbosacral area or the low back. Neither pain nor fatigue was related to the type of curve, the preoperative degree of curvature, the degree of curvature as seen on the most recent radiograph, the extent of fusion into the lumbar spine, or the presence of a broken rod. Twenty-one years after the operation, the patients were functioning quite well compared with the control subjects.

Mark Jameson's physic plants, a sixteenth century garden for gynaecology in Glasgow?

Deputy Rector of the University of Glasgow and a vicar choral of Glasgow Cathedral, the physician Mark Jameson made many annotations in his copy of the 1549 edition of Fuchs' herbal. On the back flyleaf are the names of 26 plants, 22 of which were "To be sett & sawin in ye garding". Many of the 26 plants have gynaecological properties; some are even abortifacient, especially the highly dangerous savin, Juniperus sabina.

Surgical therapy for congenital dislocation of the hip in patients who are twelve to thirty-six months old.

Over a ten-year period, fifty-one congenitally dislocated hips in forty-one patients, whose ages ranged from twelve to thirty-six months, required open reduction. Supplemental procedures such as derotational osteotomy, pericapsular (Pemberton) osteotomy, and femoral shortening were performed as necessary. All of the patients have been followed for at least two years (average, 6.1 years). No patient had a significant limp, Trendelenburg gait, or avascular necrosis. Using Severin's classification of radiographic evaluation, twenty-nine hips (57 per cent) were rate as excellent and eighteen hips (35 per cent), as good. In our experience, open reduction of the hip together with correction of acetabular and femoral deformities affords the patient in the one to three-year-old age range an excellent chance of obtaining an anatomically satisfactory hip.

Paralytic spinal deformity following traumatic spinal-cord injury in children and adolescents.

We attempted to evaluate the effect on the spinal column of loss of muscular support following trauma to the spinal cord during childhood. The cases of fifty patients, newborn to seventeen years old at the time of injury, were analyzed. Thirty-one patients had scoliotic curves of more than 20 degrees; twenty-one of these were long paralytic curves of 40 degrees or more. Age at injury was the single most important risk factor in the development of scoliosis; spasticity was also a very significant factor. Patients with lesions at all neural levels were at risk, while laminectomy was not a significant cause of scoliosis. On lateral roentgenograms the predominant finding was a reversal of the lumbar lordosis into a kyphosis, with the resultant development of a long thoracolumbar kyphosis. In five patients the opposite deformity, thoracolumbar lordosis, developed.

Clinical review of patients with broken Harrington rods.

The medical records and roentgenograms of 2,016 patients who were operated on from 1961 through 1974 using Harrington spinal instrumentation were reviewed to determine the incidence, clinical significance, and management of broken distraction and compression rods. The cases were divided into two study groups. Group A includes 1,128 patients operated on from 1961 through 1968, when no autogenous iliac-bone graft material was used, and Group B includes 888 patients operated on from 1969 through 1974, when autogenous bone was used. The incidence of broken distraction rods was 12.5 per cent (141 patients) in Group A and 2.1 per cent (nineteen patients) in Group B. The age of the patient at operation was not found to be a significant factor when comparing patients with fractured rods and those with intact rods; however, preoperative curve magnitude was found to influence the incidence of rod fractures. Reinstrumentation of distraction rods was required in twenty-three patients from Group A, but no patients in Group B required reinstrumentation. Eleven patients from Group A required removal of the rods. The compression rod fractured in forty patients (3.5 per cent) in Group A and in one patient in Group B; none required reinstrumentation or rod removal. The clinical management of rod fractures must be individualized for each patient. Reinstrumentation and fusion may be indicated in patients with early rod fracture, total loss of correction, or overlapping of the rod, but not in patients experiencing little or no loss of correction and no associated symptoms.

Association of congenital anomalies of the spine and kidneys.

Specific congenital malformations of the spine are consistently associated with characteristic types of urinary tract malformation. Patients with defects of the spine such as spina bifida occulta, partial or complete absence of the sacrum, unilateral or bilateral failure of segmentation, and wedged vertebrae are not usually associated with congenital urinary tract malformations. Spina bifida and myelomeningocele have a low incidence of urinary tract abnormalities (2.1% in this study). If there are other spine abnormalities associated with spina bifida, the incidence or urinary abnormalities increase 10 times. However, hemivertebrae occurring alone in patients or occurring in conjunction with other anomalies of the spine, are most frequently associated with urinary tract abnormalities (66%). Hemivertebrae of the low cervical and upper thoracic spine carries the highest incidence of associated urinary tract malformation.

Results of Harrington instrumentation in the treatment for severe scoliosis.

Between July 1963 and December 1974, we surgically treated 207 patients who had severe scoliosis (curves greater than 90 degrees), 196 of whom were eligible for inclusion in this study. No patient was treated preoperatively with a cast or traction. Upon statistical analysis, age and preoperative curve magnitude proved to be significant variables relative to the amount of surgical correction obtained and the maintenance of that correction; sex and etiology of the scoliosis were not shown to affect either surgical outcome or maintenance of correction. A comparative analysis showed our results to be as good as those reported by others using various preoperative regimens of casting or traction or both. Therefore, we find that the preoperative application of traction to patients with severe scoliosis yields no better correction than the use of Harrington instrumentation and fusion alone.