Nerve growth factor expression and innervation of the painful intervertebral disc.

Following a previous description of nociceptive nerve fibre growth into usually aneural inner parts of painful intervertebral disc (IVD), this study has investigated whether nociceptive nerve ingrowth into painful IVD is stimulated by local production of neurotrophins. Immunohistochemistry and in situ hybridization have been used to investigate expression of the candidate neurotrophin, nerve growth factor (NGF), and its high- and low-affinity receptors trk-A and p75, respectively, in painful IVD excised for the management of low back pain. IVD from patients with back pain were of two types: those that when examined by discography reproduced the patient symptoms (pain level IVD) and those that did not (non-pain level IVD). Microvascular blood vessels accompanied nerve fibres growing into pain level IVD and these expressed NGF. The adjacent nerves expressed the high-affinity NGF receptor trk-A. These vessels entered the normally avascular IVD through the discal end plates. NGF expression was not identified in non-pain level or control IVD. Some non-pain level IVD had vessels within them, which entered through the annulus fibrosus. These did not express NGF nor did nerves accompany them. These findings show that nociceptive nerve ingrowth into painful IVD is causally linked with NGF production by blood vessels growing into the IVD, from adjacent vertebral bodies.

Cervical percutaneous laser disc decompression: preliminary results of an ongoing prospective outcome study.

OBJECTIVE: This study identifies the efficacy of laser disc ablation and compares the relative efficacy of Holmium2100; YAG and KTP532 laser wavelengths in the treatment of broad-based cervical disc protrusions presenting with cervical axial pain with compressive or noncompressive radicular symptoms. BACKGROUND: A preliminary report on a prospective outcome study of cervical laser disc ablation and decompression in the management of cervical disc prolapse and discographically confirmed discogenic pain in association with radicular pain. METHODS: Patients with chronic cervical pain and radicular symptoms unresponsive to conservative treatment were assessed with magnetic resonance (MR) scans. Those with broad-based disc bulge or discal degeneration were assessed with provocative discography to isolate the source of pain. Percutaneous laser disc decompression was performed as a day case procedure on 105 patients at 108 levels under X-ray control via the anterior approach with side-firing probes in patients. RESULTS: At a minimum follow up of 24 months, 51% of patients demonstrated a sustained significant clinical benefit with an additional 25% in whom functional improvement was noted. No difference in outcome was identified either with the wavelengths used or with laser annealing or painful discal tears. The cohort integrity of the study was 80%. CONCLUSION: The sustained nature of the benefit (mean 3.5 years at final follow up) after long-term preoperative symptoms (mean 3.9 years) in 76% patients rules out placebo effect. Benefits occurred independently of the wavelength of laser used.

Endoscopic foraminoplasty: a prospective study on 250 consecutive patients with independent evaluation.

OBJECTIVE: This study focused on the efficacy of endoscopic decompression of the foramen guided by endoscopic aware-state pain source definition. BACKGROUND DATA: Endoscopic foraminoplasty consists of undercutting of the facet joint and endoscopic discectomy, mobilization and neurolysis of the exiting and transiting nerves, and ablation of osteophytes. This study sought the outcome of endoscopic foraminoplasty in 250 consecutive patients followed for a minimum of 2 years, reviewed and assessed by an external independent assessor. It was applied to patients with back pain and sciatica in multilevel degenerative disc disease and also to those with prior surgery. METHODS: A prospective study of endoscopic laser foraminoplasty was performed on 121 males and 129 females with an average age of 48 years (21-86 years), followed for an average period of 30 months (26-43 months). The average preoperative duration of back, buttock, or leg pain was 6.1 years (5-11 years). A total of 30% had undergone prior open spinal surgery. RESULTS: The cohort integrity at follow up was 97%. Outcome was analyzed using the percentage change in Oswestry Disability Scores and visual analogue pain scores. Clinically relevant change in pain and disability was observed in 73%. Using a percentage change in Oswestry Disability Score of 50 or more to determine good and excellent outcomes, 60% of patients exceeded this score. A total of 95% patients required no further surgical intervention. CONCLUSIONS: Endoscopic laser foraminoplasty provides a minimalist means of exploring the extraforaminal zone, the foramen, the disc, and the epidural space and performing discectomy, lateral recess decompression, osteophytectomy, and neural mobilization. Performed in the aware state, it serves to identify and localize precisely the causal source of pain in multilevel disc disease, in revision surgery, and in the infirm and elderly without open fusion or decompression.

Review of safety in endoscopic laser foraminoplasty for the management of back pain.

OBJECTIVE: The purpose of this study was to analyze the incidence and gravity of reported complications that arise in spinal surgery and assess the comparative safety, or otherwise, of endoscopic laser foraminoplasty (ELF). BACKGROUND DATA: Chemonucleolysis, decompression, discectomy, and fusion have long been cited as treatments for chronic low back pain. Over recent years newer, less invasive surgical techniques have become available, one such being ELF. Although minimally invasive, the beneficial outcome must be interpreted in relation to concerns regarding the safety of the procedure and its risks relative to those of other forms of spinal surgery. The Spinal Foundation, Rochdale has performed 958 ELFs and has collated a comprehensive database of the results of all these operations. These prospective records provided the basis for a comparison of the safety of ELF to that reported with other spinal surgical techniques. METHODS: A total of 958 procedures have been performed on 716 patients. Complications that arose during the operation and the postoperative phase of 6 weeks following the procedure were elicited from patient records. These data were correlated and compared to a meta-analysis of randomized controlled clinical trial data of complications arising during and after conventional spinal surgery. The SPSS (statistical package for social sciences) and CIA (confidence interval analysis) statistical packages were used to draw conclusions regarding the safety of ELF. RESULTS: The cohort integrity of operation and outpatient review records at 6 weeks after surgery was 100%. In 958 ELFs performed, 24 complications occurred in 23 patients. There were 9 cases of discitis (1 infective, 8 aseptic) (0.9%), 1 dural tear (0.1%), 1 deep wound infection (0.1%), 2 patients suffered a foot drop (1 transient) (0.2%), 1 myocardial infarction (0.1%), 1 erectile dysfunction (0.1%), and 1 patient who developed panic attacks post-operatively (0.1%). This amounts to an overall surgical complication rate of 1.6%. Magnetic resonance imaging (MRI) follow up of clinically symptomatic patients highlighted 8 residual disc herniations (0.8%). Meta-analysis of randomized controlled trials of conventional spinal surgery for adult onset degenerative disc disease and/or sciatic pain reported overall complication rates for fusion (11.8%), decompression (7.6%), discectomy (6.0%), and chemonucleolysis (9.6%). CONCLUSIONS: The complication rate of ELF is shown to be significantly lower than that reported following conventional spinal surgery (p < 0.01). From these results, we conclude that ELF as a treatment for chronic low back pain and sciatica presents less risk to a patient than conventional methods of spinal surgery.

Comparative outcome of Holmium: YAG and KTP laser disc ablation in degenerative cervical disc disease: results of an ongoing study.

Objective. This prospective study was designer to identify the relative efficacy of Holmium2100: YAG and KTP532 laser wavelengths in the treatment of broad based cervical disc protrusions presenting with cervical axial pain with compressive or non compressive radicular symptoms.
Methods. Patients with chronic cervical pain and radicular symptoms unresponsive to conservative treatment were assessed with MR scans. Those with broad based disc bulges were assessed with provocative discography to isolate the source of pain. Percutaneous laser disc decompression was performad as a day case procedure on 105 patients at 108 levels under X-ray control via the anterior approach with side firing probes. Vernon-Mior cervical disability and visual analogue pain indices were used to assess the outcome of the procedures.
Results. At a minimum follow up of 12 months 50% of patients demonstrated a sustained significant (excellent to good) clinical benefit with an index value of 50% or more while an additional 25% demonstrated functional improvement. No difference in outcome was identified with either wavelength utilized or with laser annealing or painful discal tears. At this juncture the cohort integrity of the study is 74%.
Conclusion. The outcome of treatment for cervical degenerative disc disease with compressive or non compressive radicular symptoms with KTP or Holmium: YAG laser is identical. The sustained nature of the benefit after long term preoperative symptoms (mean 3,4 years) rules out placebo effect.

Accurate knowledge about suicide.

Accurate knowledge about suicide among 150 English students was not associated with age, sex, personality, or attitudes toward suicide.

Endoscopic laser foraminoplasty on the lumbar spine--early experience.

Since April 1995 this endoscope assisted laser technique has been used for widening the lumbar exit route foramina. Patient selection included individuals with primarily unilateral sciatica as well as low back pain and referred buttock pain following various operative interventions. Endoscopic laser foraminoplasty (ELF) utilises an endoscope, a uniportal posterolateral approach and a side firing holmium laser probe. Under direct vision and within the protection of saline solution, epidural scarring, extruded and sequestrated disc protrusions and/or osteophytes are removed by holmium laser ablation. The patient is responsive and aware under neurolept analgesia and this ensures the protection and the integrity of the nerve root. A total of 219 such interventions has been performed up to January 1, 1997. The first 48 cases with a follow-up exceeding 12 months have been included in this preliminary review. Initial experience is encouraging. The ELF seems to provide another means of addressing sequelae of primary degenerative disorders as well as the common consequences of conventional spine surgery. ELF provides an alternative to minimal intervention fenestrectomy and open surgical undercutting for predominantly unisegmental and unilateral lateral recess stenosis and in selected cases it may prevent or delay the indication of spinal fusion.

Comparison of the Petrifilm dry rehydratable film and conventional culture methods for enumeration of yeasts and molds in foods: collaborative study.

A collaborative study was performed involving 18 laboratories and 6 food types to compare 3M Petrifilm yeast and mold count plates with the method described in the U.S. Food and Drug Administration's Bacteriological Analytical Manual. Four species of mold and 2 species of yeast were used to inoculate the following foods: hot dogs, corn meal, ketchup, orange juice, yogurt, and cake mix. Each collaborator received 15 samples of each food type: 5 low-level inoculations, 5 high-level inoculations, and 5 uninoculated samples. There was no significant difference between the means of the 2 methods for any product or inoculation level. The Petrifilm yeast and mold count plate method for enumeration of yeasts and molds in foods has been adopted first action by AOAC INTERNATIONAL.

TECRA Listeria Visual Immunoassay (TLVIA) for detection of Listeria in foods: collaborative study.

A collaborative study involving 26 laboratories and 5 food types was performed to compare the TECRA Listeria Visual Immunoassay (TLVIA) with standard culture methods. Three foods (lettuce, ice cream, and fish fillets), under the jurisdiction of the U.S. Food and Drug Administration, and 2 foods (cooked chicken and cooked ground turkey), under the jurisdiction of the U.S. Department of Agriculture, were used to determine the effectiveness of the TLVIA. Of the 900 samples tested, 300 were inoculated with low levels (1-5 cells/25 g) of Listeria spp. and 300 were inoculated with high levels of Listeria spp. (10-50 cells/25 g). Method agreement between the conventional culture methods and TLVIA (visual) was 94.7%. Method agreement between the conventional culture methods and TLVIA (reader) was 93.6%. The colorimetric polyclonal enzyme immunoassay (TLVIA) for detection of Listeria in foods has been adopted first action by AOAC INTERNATIONAL.

A family study describing second cousins with cystic fibrosis and no common ancestor who is a carrier.

We describe an extended pedigree in which second cousins are affected with cystic fibrosis (CF). Since the degree of relationship of the affected subjects is 1/32, common descent of one CF mutation was expected when the DNA laboratory undertook mutation analysis. Mutation testing showed that each CF mutation was introduced into the family by random mating and not by descent through a common ancestor. Implications for pedigree analysis and DNA testing are discussed.

Gram-negative identification card for identification of Salmonella, Escherichia coli, and other Enterobacteriaceae isolated from foods: collaborative study.

Twelve laboratories evaluated the Gram-Negative Identification (GNI) Card to identify members of the Enterobacteriaceae. Eighty-four isolates, previously isolated from foods, were used in the collaborative study; the isolates represented 12 genera within the Enterobacteriaceae group. Each collaborator streaked each isolate on tryptic soy agar plates for purity. In the method, plates are incubated 18-24 h at 35 degrees C. Isolated colonies are then subcultured to tryptic soy agar slants and incubated 18-24 h at 35 degrees C. An emulsion is made from the growth on the slant in 1.8 mL 0.45% sodium chloride solution. The GNI Card is filled and placed in a reader/incubator. Isolates are identified and an identification is printed. The Vitek System correctly identified 96.7% of Salmonella sp., 97.0% of Escherichia coli, and an average of 93.8% of the other enteric genera. The method using the Vitek System and GNI Card has been approved interim official first action by AOAC as a screening method for the presumptive identification of Salmonella sp., E. coli, and other Enterobacteriaceae isolated from foods.

Industry perspectives on Listeria monocytogenes.

Industry concerns and our ongoing research on Listeria are discussed in this report. Topics include sampling for analysis; sanitizers and their use in manufacturing facilities; precautions on use of the FDA method for Listeria; use of the Vitek Gram Positive Identification Card; and a brief discussion on findings of Listeria in environmental samples taken from the same site at the same time of year in 1986 and 1987.

The effect of intermittent pneumatic compression on the hand after fasciectomy.

Thirty-nine patients undergoing surgery for Dupuytren's contracture were included in a fully randomised, matched, prospective trial to evaluate the effect of intermittent compression on the post-operative hand. The study revealed a definite improvement in the treated, over the control patients. There was a distinct decrease in oedema with almost immediate return to normal hand function in the group treated by compression. Other benefits accrued from the earlier subsidence of pain in treated hands requiring reduced or no analgesia and from the earlier expression of fluid discharge from the wound thus preventing haematoma formation and the consequent ills.

The stripping of varicose veins: a clinical trial of intermittent compression dressings.

This study compares a standard method of care for patients following excision and ligation of varicose veins with a new regimen which involves intermittent compression dressings. In a fully randomized between-patient prospective trial it has been found that the use of such dressings results in a significant reduction in postoperative pain and in the length of hospitalization and indicates that such dressings may improve the healing of surgical wounds.

Postoperative pulmonary perfusion defects: their natural history, origin and significance.

Unmatched perfusion defects occur during the early postoperative period. These defects can persist until the tenth postoperative day and their presence is not related to the transfusion of blood or to peripheral thrombosis detected by the 125I-labelled fibrinogen uptake test. It is suggested that prophylactic agents against deep venous thrombosis should be evaluated by using a combination of krypton ventilation-perfusion lung scans and 125I-labelled fibrinogen leg scans.

Fibrinolytic response to surgery. Labile and stable patterns and their relevance to post-operative deep venous thrombosis.

Fibrinolytic activity after elective abdominal surgery was studied in 53 middle-aged cancer-free patients. The pattern of their response demonstrated both stable and labile populations. In 10 of the 13 patients in whom fibrinolytic activity fell rapidly to below 5-6 units, deep venous thrombosis (D.V.T.) developed on the first postoperative day. This suggests that reduced fibrinolytic activity after operation is involved in the establishment of postoperative D.V.T. and that the incidence of early thrombosis could be reduced by enhancement of postoperative levels of fibrinolytic activity.

Effect of intermittent compression of the arms on deep venous thrombosis in the legs.

Despite the presence of venostasis in the legs, intermittent compression of the arms during and after surgery reduced the incidence of deep venous thrombosis (D.V.T.) in the legs to half that in control patients and maintained blood fibrinolytic activity at preoperative values. It is suggested that the release of fibrinolytic activators is essential to the prophylactic action of pneumatic leggings.