Fluorescence properties of o-phthaldialdehyde derivatives of amino acids.

The fluorescence properties of the products formed by reaction of o-phthaldialdehyde with amino acids and their derivatives, in the presence of thiol compounds, have been studied. The emission spectra, quantum yields, and lifetimes depend on the primary amine and thiol compound used; the observations confirm the report (Simsons, S.S., Jr. and Johnson, D.F. (1978) J. Org. Chem 43, 2886--2891) that the product incorporates molecules of all three types of compounds. The fluorescence quantum yields of o-phthaldialdehyde derivatives of the naturally occuring amino acids ranged from 0.33 to 0.47, using 2-mercaptoethanol as the thiol compound. The fluorescence lifetimes were about 18--20 ns. Lower quantum yields were obtained when mercaptoethanol was replaced by dithiothreitol or ethnethiol. Derivatives of amino acid amides and peptides had quantum yeilds as low as 0.03, due to quenching by the carboxamide group. The intramolecular quenching was relieved by the detergent, sodium dodecyl sulfate, and by dimethylsulfoxide. Monosubstituted lysine exhibited a normal fluorescence, but the di-substituted product was largely quenched, presumably due to interaction between the two isoindole fluorophors. Fluorscence stopped-flow experiments showed that the alpha- and epsilon-amino groups reacted at different rates, with the epsilon-amion group reacting 10 times faster, with a t 1/2 of about 6 s under pseudo first order conditions at pH 9.0 with 10(-3) M o-phthaldialdehyde. The amount of instability shown by the o-phthaldialdehyde derivatives depended on the thiol compound used, the primary amine involved, and the solvent. Cysteine and o-phthaldialdehyde reacted to give an unstable, weakly fluorescent product; but cysteine could be assayed normally if its sulfhydryl was blocked. The o-phthaldialdehyde reagent was discussed in relation to fluorescamine, another reagent for primary amines.

Expression and regulation of Ly-6 differentiation antigens by murine osteoblasts.

Osteoblasts arise from mesenchymal stem cells and differentiate to become osteoid-secreting cells. However, little is known about these cells during their stages of differentiation. One reason for this lack of information is that there is no reliable method to identify osteoblasts as they mature. One method that has been used successfully with other cell types is the identification of plasma membrane-expressed differentiation antigens. The Ly-6 multigene family encodes differentiation antigens originally detected on lymphoid cells. Primary murine osteoblasts and the osteoblast-like MC3T3 cell line were examined for expression of Ly-6 antigens by flow cytometry. Primary osteoblasts and MC3T3 cells constitutively expressed both Ly-6A and Ly-6C antigens, although Ly-6C was much less abundant. Antigen expression was markedly increased by pretreating the cells with interferon-alpha/beta or -gamma. Northern blot analysis revealed constitutively expression of Ly-6 messenger RNA that was up-regulated by interferon treatment. Pretreatment of the cells with transforming growth factor-beta 1 or 1,25-dihydroxyvitamin D3 diminished constitutive Ly-6 expression. Ly-6 was localized intracellularly to the Golgi complex. The current results demonstrate that mature osteoblasts express on their cell surface specific Ly-6 antigens in a pattern that distinguishes them from the surrounding bone marrow cells. These studies represent the first identification of osteoblast differentiation antigens that can be directly related to cells within the hematopoietic lineage. By identifying similar antigens, osteoblasts at various stages of differentiation may be identified, isolated, and characterized.

Electromyographic analysis of grand-plié in ballet and modern dancers.

PURPOSE: The purpose of this report is to describe lower extremity muscle activity in grand-plié, as determined by EMG analysis; to compare and contrast muscle function in grand-plié and demi-plié to support the hypothesis that grand-plié is not simply a deeper demi-plié, but rather a fundamentally different movement in terms of muscle use; and to present further evidence in support of the hypothesis that ballet dancers use muscles differently than modern dancers in dance movement. METHODS: Surface electromyography was used to analyze lower extremity muscle activity during grand-plié in first position with lower extremities turned out in five ballet and seven modern female professional dancers. RESULTS: Electromyographic (EMG) activity of tibialis anterior included continuous activity from heel-off during the lowering phase, through midcycle, and ending at heel-on during the rising phase in all grand-pliés; the majority of tibialis anterior EMG tracings in ballet dancers had additional activity at the end of the rising phase. All EMG tracings for vastus lateralis and medialis included a peak of activity during the lowering phase, a decrease (valley) at midcycle, followed by another peak during the rising phase; increased activity at the end of the rising phase was observed in most grand-plié in ballet, and not modern, dancers. Adductor EMG activity was also observed in all tracings with a peak during the lowering phase from heel-off to midcycle, a valley at midcycle, followed by a peak of activity in early rising phase; the midcycle valley was of lower, and the rising phase peak of higher, activity in ballet compared with modern dancers. Variation of EMG patterns was observed for lateral and medial gastrocnemius, gluteus maximus, and hamstrings. CONCLUSIONS: The data support the concept that lower extremity muscle activity in dance movement is comprised of three major types: (a) unique, characteristic activity required for the execution of the movement; (b) varied activity which is characteristic of dancers of different dance idioms; and (c) varied activity which may depend on factors such as balance, personal habit, and individual training background. Furthermore, EMG activity of vastus lateralis and medialis at the midcycle valley in grand-plié was significantly less in ballet dancers than in modern dancers despite similar degree of knee flexion, suggesting that ballet dancers may have lower patellofemoral joint reaction force at midcycle than modern dancers.

Electromyographic analysis of standing posture and demi-plié in ballet and modern dancers.

Surface electromyography was used to analyze lower extremity muscle activity during standing posture and demi-plié in first position with lower extremities turned out, in five ballet and seven modern female professional dancers. In standing posture, increased electromyographic (EMG) activity above baseline was detected most frequently at the medial gastrocnemius (54% standing repetitions) and tibialis anterior (29%) electrodes (all dancers); in ballet dancers, increased EMG activity during standing was significantly less frequent at the medial gastrocnemius, but more frequent at the tibialis anterior, than in modern dancers. In demi-plié, the tibialis anterior had a discrete peak of EMG activity at midcycle in all dancers (97% demi-pliés). All dancers also had midcycle EMG activity in both vastus lateralis and medialis (100% demi-pliés). At the end of rising phase of demi-plié, ballet dancers had greater EMG activity than at midcycle in vastus lateralis (100% demi-pliés) and medialis (92%); in modern dancers, end-rising phase voltage was lower than at midcycle for vastus lateralis (71% demi-pliés) and medialis (83%). Genu recurvatum > or = 10 degrees was observed at the beginning and end of demi-plié in all ballet dancers, but not in modern dancers. There was marked variation of EMG activity during demi-plié in the lateral gastrocnemius, medial gastrocnemius, gluteus maximus, hamstrings, and adductors. The results support the hypothesis that ballet and modern dancers have different patterns of muscle use in standing posture and demi-plié, which in part may be a result of differences in genu recurvatum and turnout between the two groups.

Occupational disorders of the foot and ankle.

Occupational problems of the foot and ankle have received less attention than those of other body regions, namely the hand, neck, and lumbar spine. Functional requirements of the foot and ankle differ from other body regions, necessitating a different clinical approach to injuries than those indicated in the upper extremity or back. This article reviews the clinical characteristics of the foot and ankle pertinent to the worker and highlights the unique features of the management of foot and ankle problems encountered in occupational orthopedic practice.

Containment bag for jet lavage irrigation of the foot and ankle.

A clear plastic surgical bag which has an incorporated closure string may be used to contain fluid during jet lavage irrigation of foot and ankle wounds. This method may prevent fluid from spraying about, improving barrier precautions for both patient and operating room personnel.

Digital photography in orthopaedic surgery.

Digital photography has become a practical alternative to film photography for documentation, communication, and education about orthopaedic problems and treatment. Digital cameras may be used to document preoperative and postoperative condition, intraoperative findings, and imaging studies. Digital photographs are captured on the charged coupler device (CCD) of the camera, and processed as digital data. Images may be immediately viewed on the liquid crystal display (LCD) screen of the camera and reshot if necessary. Photographic image files may be stored in the camera in a floppy diskette, CompactFlash card, or SmartMedia card, and transferred to a computer. The images may be manipulated using photo-editing software programs, stored on media such as Zip disks or CD-R discs, printed, and incorporated into digital presentations. The digital photographs may be transmitted to others using electronic mail (e-mail) and Internet web sites. Transparency film slides may be converted to digital format and used in digital presentations. Despite the initial expense to obtain the required hardware, major cost savings in film and processing charges may be realized over time compared with film photography.

Nonoperative treatment of metatarsophalangeal joint synovitis.

The results of nonoperative treatment of metatarsophalangeal (MP) joint synovitis in 13 patients without known rheumatologic conditions (15 joints) were reviewed. Average duration of forefoot pain was 4 +/- 3 months (range 0.5-12 months), except for one patient who had pain for 30 months. The second MP joint was involved in nine cases (60%), and the third was involved in six cases (40%). Examination revealed tenderness and palpable fullness of the MP joint in all cases; painful dorsal drawer sign was present in 10 cases (67%), adjacent interdigital tenderness in six cases (40%), and hammertoe deformity in eight cases (53%). Treatment included intra-articular corticosteroid injection and rocker-sole show modification to limit MP joint dorsiflexion. At follow-up evaluation (18 +/- 9 months, range 4-26 months), the involved MP joint was asymptomatic in nine joints (60%), improved or almost asymptomatic in five joints (33%), and operated in one (7%) joint. Two of seven (29%) joints not initially associated with hammertoe developed a mild hammertoe deformity from time of diagnosis to follow-up. In conclusion, nonoperative treatment can be effective for MP joint synovitis, and the incidence of progressive hammertoe deformity in successfully treated cases is low.

Immobilization with removable walking brace for treatment of chronic foot and ankle pain.

Fifty feet and ankles in 47 patients (three bilateral) (26 women and 21 men; average age, 44+/-15 years) were treated for chronic foot and ankle pain (duration: minimum, three months; average, 27+/-35 months; range, three to 132 months). Evaluation included detailed history, physical examination, and radiography. Initial treatment consisted of immobilization (full weight-bearing) using a removable walking brace (23.5 hours per day, including in bed at night), with standing and walking limited to activities of daily living. Follow-up evaluation included assessment of pain response and repeat physical examination. There was a history of trauma in 32 (64%) feet and ankles. Braces (pneumatic in 31 [62%] and double-upright in 19 [38%] feet and ankles) immobilized the ankle in neutral position and included a rigid rocker sole. After an average of 13+/-10 weeks (range, three to 50 weeks) of brace use, pain symptoms were improved in 35 (70%), unchanged in 11 (22%), and worse in four (8%) feet and ankles. Physical examination was improved in 43 (86%) feet and ankles, unchanged in six (12%) feet and ankles, and worse in one (2%) foot and ankle. In all 50 feet and ankles, the average number of abnormal physical findings decreased from initial (6+/-3 abnormal physical findings) to follow-up evaluation (3+/-3 abnormal physical findings) (P < 0.001). The average number of diagnoses per foot and ankle decreased from initial (4+/-1 diagnoses per foot and ankle) to follow-up evaluation (2+/-1 diagnoses per foot and ankle) (P < 0.0001). Improvement of pain was independent of duration of pre-existing symptoms, patient age, gender, or type of brace used. In summary, immobilization with a removable walking brace may improve chronic foot and ankle pain and localize the primary source of symptoms.

Treatment of plantar fasciitis with a night splint and shoe modification consisting of a steel shank and anterior rocker bottom.

Seventy-one feet in 57 patients with plantar fasciitis were treated with the combination of a night splint and a shoe modification consisting of a steel shank and anterior rocker bottom. At average follow-up of 16 months, symptoms were resolved in 42 (59%), improved in 13 (18%), not changed in 11 (15%), and worse in 5 (7%) of the feet. No relation was found between outcome and age, gender, duration of symptoms, and bilateral involvement. The method is effective for the treatment of plantar fasciitis.

Partial rupture of the flexor hallucis longus tendon in a tennis player: a case report.

A 39-year-old woman sustained a forced dorsiflexion injury to the left great toe while pivoting to the right during tennis activity. Posteromedial ankle pain was reproduced with active plantarflexion and passive dorsiflexion of the great toe and, to a smaller extent, the lesser toes. Symptoms persisted for 9 months despite nonoperative treatment. Magnetic resonance imaging 5 months after injury revealed evidence of fluid surrounding the flexor hallucis longus (FHL) tendon. Operative findings 9 months after injury included scar tissue and tenosynovitis of the FHL and flexor digitorum longus tendon sheaths, with impingement of distal FHL muscle fibers and a longitudinal split tear (partial rupture) of the FHL tendon. Tenolysis, tenosynovectomy, excision of the distal muscle fibers, and repair of the partial tendon rupture were performed, resulting in resolution of symptoms. Partial rupture of the FHL tendon as a single-impact injury, or in activity other than ballet, has not been documented previously.

Detection of wooden foreign bodies in muscle tissue: experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography.

An experimental study was performed to compare computed tomography (CT), magnetic resonance imaging (MRI), and real-time, high resolution ultrasonography (US) for the detection of wooden foreign bodies in muscle tissue. Wooden splinters were prepared, measured for size, soaked in saline, and placed in porcine muscle distant from and adjacent to bone. The specimens were then examined using roentgenography, CT and MRI in planes parallel and perpendicular to the splinters, and US. The largest wooden foreign bodies (minimum smallest width = 10 mm) were easily detected by CT, MRI, and US. Almost all splinters of various sizes, small and large, soaked in saline for 5 months were easily detected by MRI. Smaller splinters (minimum smallest width = 1-4 mm) soaked for only 3 days and placed distant from bone were most easily detected by US; those soaked for 5 months were most easily detected by either US or MRI. The smaller splinters soaked for only 3 days and placed near bone were not reliably detected by any of the imaging methods; CT and MRI were both more sensitive than US in this situation. MRI scanning was more sensitive perpendicular than parallel to the long axis of the splinters. Therefore, either US or MRI may be the best initial imaging modality for evaluation of a suspected wooden foreign body, depending on availability of imaging method, chronicity of symptoms, and proximity to bone.

A method to facilitate suture removal.

Suture removal is facilitated when the strands are kept long and tied together. At removal, tension is applied to the long strands to pull the knot up from the skin surface, and the suture is cut with a scalpel. This method obviates the potential difficulty of finding a short suture tip with a forceps or passing the scissor tip under the knot of a tight suture, both potential causes of patient discomfort.

Guidelines for diabetic foot care. The Diabetes Committee of the American Orthopaedic Foot and Ankle Society.

Foot infection is the most common reason for hospital admission of patients with diabetes in the United States. Foot ulceration leads to deep infection, sepsis, and lower extremity amputation. Prophylactic foot care has been shown to decrease patient morbidity, decrease the utilization of expensive resources, and decrease the risk for amputation and premature death. The Diabetes Committee of the American Orthopaedic Foot and Ankle Society has developed guidelines for implementing this type of prophylactic foot care. The guidelines are arranged as follows: I. Screening for Patients Who Are at Risk for Developing Diabetic Foot Complications A. Risk Factors B. Components of Screening and Examination II. Patient Education III. Basic Treatment Guidelines A. Risk Categories B. Nail Care C. Ulcer Care IV. Referral Guidelines A. Vascular Surgery Consultation B. Orthopaedic Consultation C. Endocrinologist/Diabetologist Consultation D. Infectious Disease Consultation E. Radiologic Consultation F. Pedorthic Consultation V. Resources.

Salter-Harris III stress fracture of the proximal first metatarsal: a case report.

An intraarticular, dorsal, proximal epiphyseal stress fracture (Salter-Harris III) of the first metatarsal was identified in a 14-year-old boy. Successful fracture healing was achieved with a rocker sole shoe modification and activity limitation.

Current practice patterns in the treatment of Charcot foot.

Treatment of Charcot foot osteoarthropathy has emerged as a major component of the American Orthopaedic Foot and Ankle Society (AOFAS) Diabetes 2000 Initiative. A two-part survey described treatment patterns and current footwear use of patients with Charcot osteoarthropathy of the foot and ankle. In the first part, 94 consecutive patients with a history of Charcot foot and ankle presenting for care were questioned on their foot-specific treatment and current footwear use. A history of diabetic foot ulcer was given by 39 (41%) patients, and an infection had been present in a foot of 20 (21%) patients. The initial treatment of the Charcot foot and ankle had been a total contact cast in 46 (49%) patients, and a pre-fabricated walking boot in 19 (20%). Charcot related surgery had consisted of 76 procedures in 46 (49%) patients. Sixty-three (67%) patients were currently using accommodative footwear (depth-inlay shoes in 46 [49%], custom shoes in 10 [11%], and CROW in 7 [7%] patients), and 72 (77%) were currently using custom accommodative foot orthoses. The second part of this study consisted of a questionnaire completed by 37 orthopaedic surgeons (members of AOFAS) interested in forming a Charcot Study Group. They treated an average of 11.8 patients having Charcot foot or ankle per month. Thirty (81%) used the Semmes-Weinstein 5.07 monofilament as a screening tool for peripheral neuropathy. For treatment of Eichenholtz Stage I, 29 (78%) used a total contact cast and 15 (41%) allowed weightbearing; for Stage II, 30 (81%) physicians used a total contact cast and 18 (49%) allowed weightbearing. Although the literature contains uniform recommendations for immobilization and non-weightbearing as treatment for the initial phases of Charcot arthropathy, the results of this benchmarking study reveal that currenl treatment is varied.

Effect of foot and ankle position on tarsal tunnel compartment pressure.

Tarsal tunnel intracompartment pressures were determined in 10 fresh-frozen normal human adult cadaver specimens. With the foot and ankle held in mild plantarflexion and neutral eversion-inversion, mean tarsal tunnel pressure was minimal (2 +/- 1 mmHg). However, when the foot and ankle were positioned in full eversion, mean tarsal tunnel pressure increased to 32 +/- 5 mmHg (P < or = 0.005); in full inversion, mean pressure increased to 17 +/- 5 mmHg (P < or = 0.05). There was no significant difference in mean tarsal tunnel pressure between the everted and inverted positions. These results support the hypothesis that increased pressure within the tarsal tunnel when the foot is moved into the everted or inverted position may aggravate posterior tibial nerve entrapment. These findings may also provide an explanation for clinically observed aggravation of symptoms in these positions, night pain, and improvement of symptoms with neutral immobilization in some patients with tarsal tunnel syndrome.

Achilles tendon surgery: S-shaped surgical approach and postoperative positioning to minimize wound tension and external pressure.

For Achilles tendon surgery, an S-shaped incision may be made crossing the midline proximal to the transverse skin creases above the top of the heel counter. This incision provides wide exposure of the tendon and enables wound closure with minimal skin tension. After surgery, direct external pressure on the wound and dependent swelling of the Achilles tendon region, which may increase risks for wound dehiscence and infection, are minimized by laying the patient in the lateral decubitus or prone position to elevate the heel.

Rescue of the remnants: the British emergency medical relief operation in Belsen Camp 1945.

The British Army liberated the German concentration camp at Belsen on April 15, 1945. The thousands of inmates (estimates range from 60,000 to 78,900 inmates), mostly Jews from eastern Europe, were dying at a rate of 500-600 per day from disease, and many more were being killed by the German guards and co-workers. Diseases prevalent included typhus, tuberculosis, nutritional and infective diarrhoea, severe malnutrition and starvation, and others. Despite huge obstacles including the ongoing war effort, shortages of supplies, and limited numbers of workers, a relief operation was rapidly organized to control the typhus epidemic and salvage as many inmates as possible. The 10,000 emaciated corpses which had been lying all over the camp were collected and buried in mass graves. Inmates were disinfected with D.D.T., scrubbed in a "human laundry," and evacuated from the typhus-ridden Horror Camp (Camp 1) to a hospital organized in the barracks of the Panzer Training School (Camp 2). Feeding of the inmates was carefully regulated, and some basic medical treatment organized. The relief operation was performed by British Army units, detachments of the British Red Cross, British and Belgian medical students, and other volunteers including those from among the less debilitated inmates. Although 13,000 inmates died after the liberation despite the relief operation, thousands of others were rescued.

Food consumption, obesity and abnormal glycaemic control in a Canadian Inuit community.

Dietary and lifestyle factors may contribute to diabetes and obesity in the Canadian Inuit. We documented dietary patterns, physical activity level, obesity, blood glucose abnormalities and diabetes prevalence in a Canadian Inuit community. There were 250 Inuit residents of Repulse Bay, Nunavut, who had an interview about diet and physical activity, measurement of weight and height, and laboratory studies (194 subjects). Children, adolescents and younger adults (aged < 48 years) consumed significantly less country food and more processed snack foods and sweet drinks than older adults (aged ≥ 48 years). Only 88 of 250 subjects (35%) reported that they went out on the land once or more per week. Of the 85 children and adolescent subjects (aged 7-17 years), 11 (13%) were obese. Average body mass index for adults (aged ≥ 18 years) was 29 ± 6 kg m(-2) , and 61 adults (37%) were obese (body mass index ≥30 kg m(-2) ). In the 140 adults who had laboratory studies, 18 adults (13%) had a blood glucose abnormality, including 10 adults (7%) with impaired fasting glucose, four adults (3%) with impaired glucose tolerance and six adults (4%) with diabetes (five adults previously undiagnosed). Twelve of the 194 subjects tested (6%) had fasting insulin ≥140 pmol L(-1) (mean, 196 ± 87 pmol L(-1) ). In summary, there was a high prevalence of poor dietary choices, limited physical activity, obesity and type 2 diabetes in this Inuit community. Public health programmes are needed to improve the dietary and health status of this community.