Extension of polyphenolics by CWPO-C peroxidase mutant containing radical-robust surface active site.

Expressed as insoluble forms in Escherichia coli, native cationic cell wall peroxidase (CWPO-C) from the poplar tree and mutant variants were successfully reactivated via refolding experiments and used to elucidate the previously presumed existence of an electron transfer (ET) pathway in the CWPO-C structure. Their catalytic properties were fully characterized through various analyses including steady-state kinetic, direct oxidation of lignin macromolecules and their respective stabilities during the polymerization reactions. The analysis results proved that the 74th residue on the CWPO-C surface plays an important role in catalyzing the macromolecules via supposed ET mechanism. By comparing the residual activities of wild-type CWPO-C and mutant 74W CWPO-C after 3 min, mutation of tyrosine 74 residue to tryptophan increased the radical resistance of peroxidase up to ten times dramatically while maintaining its capability to oxidize lignin macromolecules. Furthermore, extension of poly(catechin) as well as lignin macromolecules with CWPO-C Y74W mutant clearly showed that this radical-resistant peroxidase mutant can increase the molecular weight of various kinds of polyphenolics by using surface-located active site. The anti-oxidation activity of the synthesized poly(catechin) was confirmed by xanthine oxidase assay. The elucidation of a uniquely catalytic mechanism in CWPO-C may improve the applicability of the peroxidase/H2O2 catalyst to green polymer chemistry.

Laparoscopic anterior lumbar interbody fusion with rhBMP-2: a prospective study of clinical and radiographic outcomes.

STUDY DESIGN: To prospectively evaluate the clinical and radiographic outcome of laparoscopic anterior lumbar interbody fusion with rhBMP-2. OBJECTIVES: It was hypothesized that discogenic pain could be treated successfully with an anterior lumbar interbody fusion performed laparoscopically using rhBMP-2 as a replacement for autogenous bone. SUMMARY OF BACKGROUND DATA: The traditional surgical treatment of discogenic pain involves painful incisions of muscles, with potential loss of integrity and strength. Harvesting of bone graft is associated with significant complications including persistent pain at the donor site. METHODS: Twenty-two consecutive patients were studied prospectively with the surgery performed by one surgeon. Patients were evaluated clinically and radiographically at 6 and 12 months after surgery. An unbiased radiologist read postoperative computed tomography scans for evidence of fusion. RESULTS: There were 8 male (36%) and 14 female (64%) patients. The average age was 38 years (range, 21-56 years). At 6 and 12 months after surgery 95% (21 of 22) were available for follow-up; 100% were satisfied with treatment at 12 months. Concerning their symptoms, 100% reported relief of back pain, 100% had improvement of leg pain, and 100% described significant functional improvement. Improvements were seen at 6 and 12 months on Oswestry (P < 0.001), functional testing (P < 0.001), and pain analog scale (P < 0.001). Radiographic analysis showed that all of the patients had evidence of a solid fusion at 6 months after operation. CONCLUSION: Discogenic low back pain can be effectively treated surgically with a laparoscopic anterior lumbar interbody fusion using rhBMP-2 in place of autogenous bone. The fusion occurs quickly and predictably with no adverse effects identified.

Cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome): meta-analysis of outcomes after medical and surgical treatments.

The cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome) is marked by slow, insidious progression and a high incidence of dural ectasia in the lumbosacral spine. A high index of suspicion for this problem must be maintained when evaluating the patient with ankylosing spondylitis with a history of incontinence and neurologic deficit on examination. There has been disagreement in the literature as to whether surgical treatment is warranted for this condition. A meta-analysis was thus performed comparing outcomes with treatment regimens. Our results suggest that leaving these patients untreated or treating with steroids alone is inappropriate. Nonsteroidal antiinflammatory drugs may improve back pain but do not improve neurologic deficit. Surgical treatment of the dural ectasia, either by lumboperitoneal shunting or laminectomy, may improve neurologic dysfunction or halt the progression of neurologic deficit.

Disproportionately severe calcinosis cutis in an 88-year-old patient with CREST syndrome.

An 88-year-old woman with CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasias) presented with hyperglycemia, intravascular depletion, and atrial fibrillation. The patient was found to have unusually severe calcinosis cutis in both legs extending from the knees to the ankles bilaterally, as well as Raynaud's phenomenon, sclerodactyly, and telangiectasias. The patient was normocalcemic and normophosphatemic. Although subcutaneous calcification is often seen with CREST syndrome, this case is unusual in that the area of involvement was much larger than previously described. Furthermore, the amount of calcinosis was disproportionately severe and was the major cause of symptoms and disability compared with the other components of the syndrome.

Dural ectasia and conventional radiography in the Marfan lumbosacral spine.

OBJECTIVE: To determine how well conventional radiographic findings can predict the presence of dural ectasia in Marfan patients. DESIGN AND PATIENTS: Twelve Marfan patients without dural ectasia and 21 Marfan patients with dural ectasia were included in the study. Five radiographic measurements were made of the lumbosacral spine: interpediculate distance, scalloping value, sagittal canal diameter, vertebral body width, and transverse process width. RESULTS: The following measurements were significantly larger in patients with dural ectasia: interpediculate distances at L3-L4 levels (P<0.03); scalloping values at the L1 and L5 levels (P<0.05); sagittal diameters of the vertebral canal at L5-S1 (P<0.03); transverse process to width ratios at L2 (P<0.03). Criteria were developed for diagnosis of dural ectasia in Marfan patients. These included presence of one of the following: interpediculate distance at L4 > or = 38.0 mm, sagittal diameter at S1 > or = 18.0 mm, or scalloping value at L5 > or = 5.5 mm. CONCLUSION: Dural ectasia in Marfan syndrome is commonly associated with several osseous changes that are observable on conventional radiographs of the lumbosacral spine. Conventional radiography can detect dural ectasia in patients with Marfan syndrome with a very high specificity (91.7%) but a low sensitivity (57.1%).

The lumbar interpediculate distance is widened in adults with the Marfan syndrome: data from 32 cases.

32 patients with Marfan syndrome, diagnosed with DePaepe's criteria, volunteered for this study. All patients underwent standard anteroposterior radiographs of the lumbar spine. Interpediculate distances (IPD) at each level were compared to those of previously established norms. Criteria were developed to determine the presence of Marfan using "cut-off values" for the IPDs at each lumbar level. The IPDs were significantly larger in the Marfan patients at all lumbar levels. Cut-off values were calculated setting the specificity at 95% at each lumbar level. The cut-off value at L4 yielded the greatest sensitivity. We conclude that the IPDs are widened in patients with Marfan syndrome. The IPD at L4 is a good criterion for Marfan with specificity of 95% and sensitivity of 75%. One must consider using this as a skeletal criterion or a screening tool for Marfan.

Early failure associated with the use of Hylamer-M spacers in three primary AMK total knee arthroplasties.

We report 3 cases of early failure associated with AMK total knee arthroplasties with the use of Hylamer-M spacers. In 2 of these cases, massive osteolysis of the posterior condyles was noted; revision with the use of allograft bone to fill in the cavitary defects yielded excellent results. In all cases, large areas of pitting and delamination of the Hylamer spacers were noted. Given these cases and the previous literature on early failure of hip arthroplasties with Hylamer inserts, we recommend caution in using Hylamer for knee arthroplasty surgery.

Thoracolumbar spinal abnormalities in Stickler syndrome.

STUDY DESIGN: Retrospective review of clinical and radiographic records of patients with Stickler syndrome. OBJECTIVES: To describe thoracolumbar spinal abnormalities and their correlation with age and back pain among patients with Stickler syndrome. SUMMARY OF BACKGROUND DATA: Stickler syndrome (hereditary arthro-ophthalmopathy) is an autosomal dominant connective tissue disorder characterized by skeletal, ocular, oral-facial, cardiac, and auditory manifestations. Prevalence is approximately 1 in 10,000 (similar to that of Marfan syndrome). No one has investigated spinal abnormalities in a large series of patients. METHODS: A single-center evaluation of 53 patients from 24 families with Stickler syndrome (age range, 1-70 years) in a multidisciplinary genetics clinic. Thoracolumbar radiographs were analyzed for spinal abnormalities and correlation with age and back pain. RESULTS: Thirty-four percent of patients had scoliosis, 74% endplate abnormalities, 64% Schmorl's nodes, 43% platyspondylia, and 43% Scheuermann-like kyphosis. Sixty-seven percent of patients and 85% of adults reported chronic back pain. Endplate abnormalities and Schmorl's nodes were associated with adult age; endplate abnormalities, Schmorl's nodes, and adult age were associated with back pain. Only one adult patient was free of spinal abnormalities. CONCLUSIONS: Spinal abnormalities are nearly uniformly observed in Stickler syndrome, progress with age, and are associated with back pain. Although common, scoliosis is generally self-limited (only one patient needed surgical treatment). Correct diagnosis of this syndrome facilitates early identification and management of other potentially severe systemic manifestations and genetic counseling for affected families. Moreover, recognition of Stickler syndrome allows accurate prognosis for skeletal abnormalities and anticipation of potential surgical complications.

Osseous anatomy of the lumbosacral spine in Marfan syndrome.

STUDY DESIGN: This study examines pedicle widths, laminar thicknesses, and scalloping values for lumbosacral spine elements in Marfan volunteers. Comparisons were made between these measurements and norms as well as measurements between Marfan patients with and without dural ectasia. OBJECTIVES: To determine if the lumbosacral vertebral elements are altered in the patient with Marfan syndrome. SUMMARY OF BACKGROUND DATA: Several abnormalities have been noted in Marfan lumbar spine, including pedicular attenuation and widened interpediculate distances. This may be due to abnormalities of growth or presence of dural ectasia. Given the large numbers of Marfan patients requiring spinal surgery and the high postoperative failure rate, better understanding of the bony anatomy of Marfan lumbar spine is necessary, especially if use of instrumentation is anticipated. METHODS: Thirty-two volunteers with Marfan syndrome based on the Ghent criteria underwent spiral computed tomography of the lumbosacral spine. Images were evaluated for dural ectasia, and measurements of pedicle width, laminar thickness, and vertebral scalloping were made. RESULTS: Pedicle widths and laminar thicknesses were significantly smaller in Marfan patients at all levels (P<0.001). Mean pedicle widths at L1-L3 were smaller than the smallest available pedicle screw (5 mm). In Marfan patients with dural ectasia, laminar thickness from L5-S2 and pedicle widths at all lumbar levels were significantly reduced (P<0.01). Vertebral scalloping at S1 was significantly greater in Marfan patients with dural ectasia (P = 0.02). CONCLUSION: Lumbar pedicle width and laminar thickness are significantly reduced in Marfan individuals. Those with dural ectasia demonstrate increased bony erosion of anterior and posterior elements of lumbosacral spine. Preoperative planning and routine computed tomography scans are recommended when operating on Marfan lumbosacral spine.

Cauda equina syndrome secondary to lumbar disc herniation: a meta-analysis of surgical outcomes.

STUDY DESIGN: A meta-analysis of surgical outcomes of cauda equina syndrome secondary to lumbar disc herniation. OBJECTIVES: To determine the relationship between time to decompression after onset of cauda equina syndrome and clinical outcome, and to identify preoperative variables that were associated with outcomes. SUMMARY OF BACKGROUND DATA: The timing of surgical decompression for cauda equina syndrome is controversial. Although most surgeons recommend emergent decompression, results in certain studies show that delayed surgery may provide a satisfactory outcome. METHODS: A meta-analysis was performed to determine the correlation between timing of decompression and clinical outcome. One hundred four citations were reviewed, and 42 met the inclusion criteria. Preoperative and postoperative data were recorded. Length of time to surgery was broken down into five groups: less than 24 hours, 24-48 hours, 2-10 days, 11 days to 1 month, and more than 1 month. Logistic regression was used to determine the association between preoperative variables and postoperative outcomes. RESULTS: Outcomes were analyzed in 322 patients. Preoperative chronic back pain was associated with poorer outcomes in urinary and rectal function, and preoperative rectal dysfunction was associated with worsened outcome in urinary continence. In addition, increasing age was associated with poorer postoperative sexual function. No significant improvement in surgical outcome was identified with intervention less than 24 hours from the onset of cauda equina syndrome compared with patients treated within 24-48 hours. Similarly, no difference in outcome occurred in patients treated more than 48 hours after the onset of symptoms. Significant differences, however, were found in resolution of sensory and motor deficits as well as urinary and rectal function in patients treated within 48 hours compared with those treated more than 48 hours after onset of symptoms. CONCLUSIONS: There was a significant advantage to treating patients within 48 hours versus more than 48 hours after the onset of cauda equina syndrome. A significant improvement in sensory and motor deficits as well as urinary and rectal function occurred in patients who underwent decompression within 48 hours versus after 48 hours.

Dural ectasia is associated with back pain in Marfan syndrome.

STUDY DESIGN: A cross-sectional age- and sex-matched study comparing the prevalence and size of dural ectasia in two groups of patients with Marfan syndrome. Group I comprised patients with moderate to severe back pain and Group II comprised patients without back pain. OBJECTIVES: To determine whether the presence and size of dural ectasia is associated with back pain in patients with Marfan syndrome. SUMMARY OF BACKGROUND DATA: Dural ectasia is present in more than 60% of patients with Marfan syndrome. Moderate to severe back pain is present in more than 50% of patients with Marfan syndrome. Most cases of significant low back pain in patients with Marfan syndrome do not have a clear cause. It would be useful for the clinician to know whether dural ectasia may be a cause of back pain in patients with Marfan syndrome with no other source. METHODS: Thirty two volunteers aged 30-50 with Marfan syndrome were enrolled as age- and sex-matched pairs with significant back pain (Group I) and without back pain (Group II). A completed questionnaire, physical examination, and magnetic resonance image of the lumbosacral spine were obtained. Dural volume caudal to L5 was calculated from the magnetic resonance data by specially designed software. RESULTS: Dural ectasia was present in 76% of the patients in Group I, and 41% of the patients in Group II. The proportion of patients with dural ectasia was significantly higher in Group I. Furthermore, the mean dural volume was significantly higher in Group I, and a significant correlation between dural volume and Oswestry pain score was noted. CONCLUSIONS: The presence and size of dural ectasia are associated with back pain in the Marfan syndrome. However, a high prevalence of dural ectasia (41%) exists even in patients with Marfan syndrome without back pain. The mere presence of dural ectasia therefore does not necessarily mean the patient will be symptomatic even though the two are associated.

Dural ectasia in the Marfan syndrome: MR and CT findings and criteria.

PURPOSE: To create criteria for detecting dural ectasia on MR or CT images in adult Marfan patients. METHODS: Images were analyzed using a workstation. Parameters that predicted dural ectasia were included in our criteria. RESULTS: Major criteria include: (1) width of dural sac below L5 > width above L4; (2) anterior sacral meningocele. Minor criteria include: (1) L5 nerve root sleeve diameter > 6.5 mm and (2) S1 scalloping > 3.5. Dural ectasia exists if 1 major or 2 minor criteria are present. CONCLUSION: MR and CT diagnose dural ectasia with high specificity and sensitivity. Our criteria accurately diagnose dural ectasia in adult Marfan patients.

Orthopedic problems in Lesch-Nyhan syndrome.

Lesch-Nyhan syndrome is an X-linked disorder of purine metabolism. The orthopedic problems and results of treatment of nine Lesch-Nyhan patients are reviewed. Associated orthopedic problems included hip subluxation or dislocation (nine of 18 hips), fractures (three), autoamputation, infections (three), minor scoliosis, and contractures. Lesch-Nyhan patients can safely undergo orthopedic procedures and the results of surgery are satisfactory and similar to those of patients with spastic cerebral palsy. All of the seven operated-on hips maintained good reduction at 6-year mean follow-up. With adequate cast technique, fractures and hip subluxation/dislocation may be treated successfully. The treating orthopedist should be aware of the increased incidence of heterotopic ossification in this population, as well as the potential for serious complications such as hardware failure or femur fracture, if appropriate immobilization is not used.

Ankle fractures. The Lauge-Hansen classification revisited.

Rational treatment of ankle fractures requires knowledge of the extent of bone and soft tissue injury. Although the Lauge-Hansen classification attempts to do this by relating specific fracture patterns to injury mechanism, the experimental underpinning for this classification has not been reexamined rigorously using modern experimental methods. This study examines the hypothesis that the clinically occurring supination and external rotation injury pattern does not result from the mechanism described by Lauge-Hansen. Thirty-two anatomic specimen ankles were mounted on an MTS machine for combined axial loading with external rotation to failure testing. A foot plate supinated the foot 25 degrees. Testing was performed with the ankle at neutral, 25 degrees plantar flexed, 10 degrees to 15 degrees dorsiflexed, and in 6 degrees to 8 degrees leg valgus. Pure supination and external rotation with the ankle in neutral did not result in the Lauge-Hansen supination and external rotation type fractures. This outcome was not altered if the ankle specimens initially were placed in plantar flexion or dorsiflexion. The addition of a valgus load, which pushes the talus laterally against the fibula, resulted in the classic Lauge-Hansen supination and external rotation type fracture. All specimens had an isolated lateral injury or a lateral injury that preceded medial injury.

Motion of the ankle in a simulated supination-external rotation fracture model.

UNLABELLED: An experimental study was undertaken with use of axially loaded, unconstrained cadaver ankles to determine the motion patterns seen with progressive stages of the supination-external rotation type of fracture. As described by Lauge-Hansen, these fractures were modeled by transection of the anterior aspect of the capsule and the anterior tibiofibular ligament (stage I), followed by oblique fibular osteotomy ending at the level of the ankle joint (stage II), transection of the posterior aspect of the capsule (stage III), and sequential sectioning of the superficial and deep fibers of the deltoid ligament (stage IV). Thirteen specimens were tested on an apparatus that allowed for controlled loading while the ankle was passed through a physiological range of dorsiflexion and plantar flexion. The ankles were unconstrained about the axial (internal and external rotation) and coronal (varus and valgus angulation) axes. Measurements were made throughout the range of motion in these axes in order to define the kinematic behavior. In the intact specimens, maximum plantar flexion was associated with a mean (and standard deviation) of 1.9 +/- 4.12 degrees of internal rotation of the talus and maximum dorsiflexion, with a mean of 7.2 +/- 3.88 degrees of external rotation. Varus angulation increased slightly with plantar flexion compared with the value in dorsiflexion (2.4 +/- 2.40 compared with 0.3 +/- 1.96 degrees). Internal and external rotation was not affected by fibular osteotomy or by transection of the superficial fibers of the deltoid ligament. Transection of the deep fibers of the deltoid ligament caused a significant (p < 0.02) increase in external rotation of the talus at maximum plantar flexion; this was corrected incompletely by insertion of an anatomical fibular plate. With the numbers available for study, we could not show that varus or valgus angulation was significantly affected by any combination of sectioning of the deltoid ligament and fibular osteotomy. These experiments were repeated with the addition of fixation of the subtalar joint with a talocalcaneal screw. With the number of specimens available, we could detect no significant difference, with respect to axial rotation, due to fixation of the subtalar joint. However, along the coronal axis, increased valgus angulation (p < 0.02) was seen during plantar flexion when either the deep or the superficial fibers of the deltoid ligament had been cut. CLINICAL SIGNIFICANCE: These results indicate that stability of the loaded ankle is primarily due to the deltoid ligament, which exerts a restraining influence on external rotation of the talus. Complete fibular osteotomy did not cause abnormal motion of the ankle in the absence of a medial injury. In the presence of a complete injury, lateral reconstruction only partially restored the mechanical integrity of the ankle. The results provide justification for the non-operative treatment of isolated fractures of the lateral malleolus. The data also suggest that a lateral fracture associated with a major injury of the deltoid ligament should be treated with anatomical lateral fixation followed by immobilization without early motion, to allow adequate healing of the deltoid ligament at its resting length.

Economic analysis of roentgenogram use in the closed treatment of stable ankle fractures.

Fractures of the ankle are one of the most commonly treated injuries by orthopedic surgeons. The adequacy of closed treatment of stable lateral malleolar ankle fractures is frequently assessed by repeated roentgenograms. There are no standards, nor studies, however, that provide guidelines as to the necessity of such roentgenograms. This study was designed to determine the average frequency of follow-up roentgenograms in ankle fractures treated by casting, as well as the clinical impact of these roentgenograms. The clinical radiographic data base of a university hospital was reviewed to identify all ankle fractures treated between January 1, 1992 and June 30, 1993. A total of 82 patients satisfied the study criteria of having sustained a stable ankle fracture that was treated by closed means, with sufficient clinical and radiographic follow-up to assess healing of the fracture. All patients healed their fractures at an average of 8.4 weeks (+/- 3.0 weeks), with weight-bearing initiated at 4.0 weeks (+/- 2.7 weeks). No patients developed radiographic evidence of a talar shift during treatment, and none required surgery for a failure of closed treatment. At no time did any ankle exhibit a significant change in fibular alignment relative to the initial injury films. Each patient had an average of 4.5 (+/- 2.0) radiographic studies performed throughout their treatment. This study indicates that secondary displacement of either the talus or fibula in a stable ankle fracture is very unusual. In conjunction with the generally excellent outcome for such fractures, this suggests that frequent roentgenograms are not justified on clinical grounds.(ABSTRACT TRUNCATED AT 250 WORDS)