Reinforcement of bacterial cellulose aerogels with biocompatible polymers.

Bacterial cellulose (BC) aerogels, which are fragile, ultra-lightweight, open-porous and transversally isotropic materials, have been reinforced with the biocompatible polymers polylactic acid (PLA), polycaprolactone (PCL), cellulose acetate (CA), and poly(methyl methacrylate) (PMMA), respectively, at varying BC/polymer ratios. Supercritical carbon dioxide anti-solvent precipitation and simultaneous extraction of the anti-solvent using scCO2 have been used as core techniques for incorporating the secondary polymer into the BC matrix and to convert the formed composite organogels into aerogels. Uniaxial compression tests revealed a considerable enhancement of the mechanical properties as compared to BC aerogels. Nitrogen sorption experiments at 77K and scanning electron micrographs confirmed the preservation (or even enhancement) of the surface-area-to-volume ratio for most of the samples. The formation of an open-porous, interpenetrating network of the second polymer has been demonstrated by treatment of BC/PMMA hybrid aerogels with EMIM acetate, which exclusively extracted cellulose, leaving behind self-supporting organogels.

Assessment of different screw augmentation techniques and screw designs in osteoporotic spines.

This is an experimental study on human cadaver spines. The objective of this study is to compare the pullout forces between three screw augmentation methods and two different screw designs. Surgical interventions of patients with osteoporosis increase following the epidemiological development. Biomechanically the pedicle provides the strongest screw fixation in healthy bone, whereas in osteoporosis all areas of the vertebra are affected by the disease. This explains the high screw failure rates in those patients. Therefore PMMA augmentation of screws is often mandatory. This study involved investigation of the pullout forces of augmented transpedicular screws in five human lumbar spines (L1-L4). Each spine was treated with four different methods: non-augmented unperforated (solid) screw, perforated screw with vertebroplasty augmentation, solid screw with vertebroplasty augmentation and solid screw with balloon kyphoplasty augmentation. Screws were augmented with Polymethylmethacrylate (PMMA). The pullout forces were measured for each treatment with an Instron testing device. The bone mineral density was measured for each vertebra with Micro-CT. The statistical analysis was performed with a two-sided independent student t test. Forty screws (10 per group and level) were inserted. The vertebroplasty-augmented screws showed a significant higher pullout force (mean 918.5 N, P = 0.001) than control (mean 51 N), the balloon kyphoplasty group did not improve the pullout force significantly (mean 781 N, P > 0.05). However, leakage occurred in some cases treated with perforated screws. All spines showed osteoporosis on Micro-CT. Vertebroplasty-augmented screws, augmentation of perforated screws and balloon kyphoplasty augmented screws show higher pullout resistance than non-augmented screws. Significant higher pullout forces were only reached in the vertebroplasty augmented vertebra. The perforated screw design led to epidural leakage due to the position of the perforation in the screw. The position of the most proximal perforation is critical, depending on screw design and proper insertion depth. Nevertheless, using a properly designed perforated screw will facilitate augmentation and instrumentation in osteoporotic spines.

Short-term outcome of painful bone marrow oedema of the knee following oral treatment with iloprost or tramadol: results of an exploratory phase II study of 41 patients.

OBJECTIVES: To compare the therapeutic effects of oral iloprost and tramadol on the outcome of bone marrow oedema (BME) of the knee by MR imaging and clinical assessment. METHODS: Forty-one patients with painful ischemic or mechanical BME of the knee were enrolled in a double-blind, randomized controlled study. Patients were randomized either to iloprost (n = 21, group 1) or tramadol (n = 20, group 2). The treatment duration was 4 weeks. The Larson knee score was used to assess function before treatment and then 3 days, 1, 2, 3, 4 weeks and 3 months after the start of treatment. Short tau inversion recovery and T1-weighted MR images of the affected knees were obtained before and 3 months after the start of treatment. Bone marrow oedema was assessed visually and by computer-assisted quantification for baseline and follow-up MR examinations. RESULTS: Thirty-three patients completed the study as scheduled. The mean Larson score improved from 58.6 points to 81.8 points in group 1, and from 59.6 points to 86.8 points in group 2, after 3 months (no significant difference between the treatment groups). On MR images, complete BME regression in at least one bone was observed in nine patients (52.9%) in group 1, as opposed to three patients (18.7%) in group 2, after 3 months (P = 0.034). Correspondingly, the median BME volume decreased by 58.0% in group 1, and by 47.5% in group 2. CONCLUSIONS: The analgesic effect of iloprost and tramadol was similar. BME regression on MR images was more pronounced under iloprost treatment.

[Bone marrow edema in the knee. Differential diagnosis and therapeutic possibilities]. / Knochenmarködem im Kniegelenk. Differenzialdiagnostik und therapeutische Möglichkeiten.

The Bone marrow edema (BME) is a common finding when evaluating patients with knee pain by magnetic resonance imaging (MRI). The typical signal patterns of BME are unspecific and can be found with different diseases of the knee. Since different therapeutic approaches are mandatory, differential diagnosis of the several forms of BME is important. In this review, painful BME will be separated into three different etiological groups. Group 1 ischemic BME: osteonecrosis, osteochondritis dissecans, bone marrow edema syndrome and complex regional pain syndrome. Group 2 mechanical BME: bone bruises, microfracture, stress-BME und stress fracture. Group 3 reactive BME: inflammatory gonarthritis, degenerative gonarthrosis, postoperative and tumours. The typical MRI morphologies and differential diagnosis of these BME manifestations will be described. The different therapeutic consequences will also be briefly mentioned.

[Differential diagnosis of bone marrow edema of the knee joint]. / Differenzialdiagnosen des Knochenmarködems am Kniegelenk.

Bone marrow edema of the knee joint is a frequent clinical picture in MR diagnostics. It can be accompanied by symptoms and pain in the joint. Diseases that are associated with bone marrow edema can be classified into different groups. Group 1 includes vascular ischemic bone marrow edema with osteonecrosis (synonyms: SONK or Ahlbäck's disease), osteochondrosis dissecans, and bone marrow edema syndrome. Group 2 comprises traumatic or mechanical bone marrow edema. Group 3 encompasses reactive bone marrow edemas such as those occurring in gonarthrosis, postoperative bone marrow edemas, and reactive edemas in tumors or tumor-like diseases. Evidence for bone marrow edema is effectively provided by MRI, but purely morphological MR information is often unspecific so that anamnestic and clinical details are necessary in most cases for definitive disease classification.

Treatment of reflex sympathetic dystrophy in children using a prostacyclin analog: preliminary results.

UNLABELLED: The aim of our study was to evaluate Iloprost, a prostacyclin analog, for treatment of reflex sympathetic dystrophy in children not responsive to conservative treatment. Seven female patients with a mean age of 9 years (range, 6-11 years) diagnosed with reflex sympathetic dystrophy Stage II were treated with infusions of Iloprost given on three consecutive days. Additionally, all patients had physiotherapy and were offered psychologic consultation. One day after the final infusion, all seven patients were free of pain and achieved full weightbearing. The side effects of Iloprost were headache in all patients and vomiting in two patients. Two patients experienced relapse--one patient at 3 months and the other patient 5 months after primary treatment--but both were free of pain by 5 days after a second series of infusions. During a mean followup of 30 months all patients remained asymptomatic. Our preliminary results suggest that temporary sympathicolysis with Iloprost, physiotherapy, and psychologic counseling is a safe and an effective treatment of reflex sympathetic dystrophy in children with a long history of symptoms or in those who do not respond to conservative treatment. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series--no, or historical control group). See the Instructions for Authors for a complete description of levels of evidence.

Ultrasound-guided needling combined with shock-wave therapy for the treatment of calcifying tendonitis of the shoulder.

We carried out a prospective, randomised controlled trial on two groups of 40 patients with painful calcific tendonitis and a mean age of 48.4 years (32.5 to 67.3). All were to undergo arthroscopic removal of the calcific deposit within six months after randomisation. The 40 patients in group I received ultrasound-guided needling followed by high-energy shock-wave therapy and the 40 in group II had shock-wave therapy alone. In both groups one treatment consisting of 2500 impulses of shock waves with an energy flux density of 0.36 mJ/mm(2) was applied. The clinical and radiological outcome was assessed using the 100-point Constant shoulder scoring system and standardised radiographs. The mean follow-up was 4.1 months and no patient was lost to follow-up. Both groups had significant improvement in their Constant shoulder score. Radiographs showed disappearance of the calcific deposit in 60.0% of the shoulders in group I and in 32.5% of group II (p < 0.05). Significantly better clinical and radiological results were obtained in group I than in group II. Arthroscopic removal of the deposit was avoided in 32 patients of group I and in 22 of group II. No severe side-effects were recorded.Ultrasound-guided needling in combination with high-energy shock-wave therapy is more effective than shock-wave therapy alone in patients with symptomatic calcific tendonitis, giving significantly higher rates of elimination of the calcium deposits, better clinical results and reduction in the need for surgery.

Chevron osteotomy in hallux valgus. Ten-year results of 112 cases.

The Chevron osteotomy was described in 1976. There have, however, been only short- to mid-term follow-up reviews, often with small numbers of patients. We looked at 112 feet (73 patients) with a minimum follow-up of ten years following Chevron osteotomy with a distal soft-tissue procedure. Clinical evaluation was calculated using the hallux score of the American Orthopedic Foot and Ankle Society (AOFAS). For 47 feet (30 patients), the results were compared with those from an interim follow-up of 5.6 years. The AOFAS-score improved from a pre-operative mean of 46.5 points to a mean of 88.8 points after a mean of 12.7 years. The first metatarsophalangeal (MTP) angle showed a mean pre-operative value of 27.6 degrees and was improved to 14.0 degrees. The first intermetatarsal (IM) angle improved from a pre-operative mean value of 13.8 degrees to 8.7 degrees. The mean pre-operative grade of sesamoid subluxation was 1.7 on a scale from 0 to 3 and improved to 1.2. Measured on a scale from 0 to 3, arthritis of the first MTP joint progressed from a mean of 0.8 to 1.7. Comparing the results in patients younger and older than 50 years, the Chevron osteotomy performed equally in both age groups. Analysing the subgroup of 47 feet with a post-operative follow-up of both 5.6 and 12.7 years, the AOFAS pain and the overall score showed a further improvement between both follow-up evaluations. The MTP angle, first IM angle and sesamoid position remained unchanged. The progression of arthritis of the first MTP joint between 5.6 and 12.7 years post-operatively was statistically significant. Only one patient required a revision procedure due to painful recurrence of the deformity. Excellent clinical results following Chevron osteotomy not only proved to be consistent, but showed further improvement over a longer follow-up period. The mean radiographic angles were constant without recurrence of the deformity. So far, the statistically significant progression of first MTP joint arthritis has not affected the clinical result, but this needs further observation.

Iloprost for the treatment of bone marrow edema in the hindfoot.

The parenteral application of the vasoactive drug, iloprost, might be a viable option for the treatment of BMES of different origins, especially ischemic ones. In edema that is secondary to osteoarthrosis or stress, the effect of therapy with iloprost depends on the grade of the basic disease. The natural course of the disease, as well as the normalization of the signal pattern of the MRI, seem to be accelerated.

Juvenile bone-marrow oedema of the acetabulum treated by iloprost.

The bone-marrow oedema syndrome is associated with local vascular disturbances and may be treated either conservatively or by core decompression after which recovery may take several weeks. We describe a 15-year-old girl with bone-marrow oedema of the left acetabulum which was confirmed by MRI. She presented with a four-week history of severe constant pain. Routine blood tests and plain radiographs were normal. She was treated with intravenous infusions of iloprost on five consecutive days (20 microg administered in 500 ml of sodium chloride). Iloprost causes vasodilatation with reduction of capillary permeability and it inhibits platelet aggregation. She had relief from pain at rest after three days of treatment and was completely free from symptoms after two weeks. MRI after six weeks showed almost complete resolution of the marrow oedema and was normal after four months. This is the first report of the pharmacological treatment of the bone-marrow oedema syndrome in children.

Intertrochanteric osteotomy for avascular necrosis of the head of the femur. Survival probability of two different methods.

We have compared different types of intertrochanteric osteotomy for avascular necrosis of the hip and evaluated their performance in the light of improving outcome after total hip arthroplasty (THA). During a period of 14 years we performed 63 flexion osteotomies (partly combined with varus or valgus displacement), 29 rotational osteotomies, 13 varus osteotomies, eight medialising osteotomies and two extension osteotomies. The mean period of follow-up for all 115 operations was 7.3 years (maximum 24.6). At follow-up, 27 of 29 patients with a rotational osteotomy had already undergone a THA, compared with 36 of 63 after flexion osteotomy. A high incidence of complications (55.2%) was seen early after rotational osteotomy, compared with 17.5% after flexion osteotomy. For all osteotomies there was a high correlation between the size of the necrotic area and the incidence of failure, which also correlated with the preoperative Ficat and Steinberg stages. Using Kaplan-Meier survivorship analysis, Sugioka's rotational osteotomy showed a survival probability after five years of 0.26 (95% confidence interval 0.49 to 0.14), and after ten years of 0.15 (CI 0.36 to 0.06). The survival probability for flexion osteotomy was 0.70 (CI 0.83 to 0.59) after five years and 0.50 (CI 0.65 to 0.38) after ten years. The subgroup of flexion osteotomy with a necrotic sector of less than 180 degrees achieved the best survival probability of 0.90 (CI 1.00 to 0.80) after five years and 0.61 (CI 0.84 to 0.45) after ten years. The indications for intertrochanteric osteotomy for avascular necrosis of the hip have to be addressed critically. Even flexion osteotomy in cases with small areas of necrosis provides only temporary benefit. Rotational osteotomy was associated with a high incidence of complications.

Core decompression in early stages of femoral head osteonecrosis--an MRI-controlled study.

We treated 45 hips with idiopathic necrosis of the femoral head stages I-III with core decompression. Average age of patients was 41 (27-68) years and average follow-up 68.9 (31-120) months. In 30 hip joints in stage I, 29 showed no radiographic progression and a complete remission of the changes consistent with necrosis on MRI at the last follow-up. In 27 patients the clinical result based on the Harris Hip Score (HHS) assessment--was excellent (average HHS 91.9 points). Of nine hips in stage II, four had received a total hip arthroplasty, one had deteriorated to stage IV, and four were still classified as stage II (average HHS 95 points). Of six hips in stage III, three had received a total hip arthroplasty and three had deteriorated to stage IV (average HHS 73 points).

Treatment of bone-marrow oedema of the talus with the prostacyclin analogue iloprost. An MRI-controlled investigation of a new method.

Bone marrow oedema syndrome of the talus is a rare cause of pain in the foot, with limited options for treatment. We reviewed six patients who had been treated with five infusions of 50 microg of iloprost given over six hours on five consecutive days. Full weight-bearing was allowed as tolerated. The foot score as described by Mazur et al was used to assess function before and at one, three and six months after treatment. The mean score improved from 58 to 93 points. Plain radiographs were graded according to the Mont score and showed grade-I lesions before and after treatment, indicating that no subchondral fracture or collapse had occurred. MRI showed complete resolution of the oedema within three months. We conclude that the parenteral administration of iloprost may be used in the treatment of this syndrome.

Reflex sympathetic dystrophy in children.

This report presents the case of an 8-year-old boy who underwent a second clubfoot operation following early-stage reflex sympathetic dystrophy (RSD). After other conditions had been ruled out, the patient was submitted to physiotherapy supported by antiphlogistic and analgesic drugs as well as a partial immobilisation of the affected extremity. He remained asymptomatic during the following 4 weeks. RSD in children is not a well-recognised entity. This case of early-stage RSD illustrates the need to be aware of this possible complications after operation in the differential diagnosis of local pain and swelling of a limb.

Radiographic evaluation of the acromion in impingement syndrome: comparison with arthroscopic findings in 147 shoulders.

We analyzed standardized scapulolateral and anteroposterior view radiographs in 147 patients with impingement syndrome to detect a subacromial osteophyte or spur, which should be of value in those patients who require surgical treatment. Standard anteroposterior view radiographs with a fixed tube angulation, 0 and 30 degrees, were compared to anteroposterior view radiographs with individual tube angulation (the radiograph beam was tilted caudally, depending on the slope of the acromion). In all patients, we identified an acromion bony overhang on the anteroposterior view radiographs with individual tube angulation having an average thickness of 5 mm, which correlated well with the intraoperative findings at arthroscopic acromioplasty. In only 35% of the patients did we detect a subacromial osteophyte or spur on radiographs with a fixed tube at 0 degrees angulation and in 92%, we found a false impression of a spur on the 30-degree views because of overexposure. We conclude that, anteroposterior view radiographs with an individual caudally-tilted X-ray beam, depending on the acromion slope, can show the whole spur and/ or size of the osteophyte, on the anterior margin of the acromion.

[Intertrochanteric rotational osteotomies in idiopathic femur head necrosis--comparison of different procedures]. / Intertrochantäre Umstellungsosteotomien bei idiopathischer Hüftkopfnekrose--Vergleich unterschiedlicher Verfahren.

PROBLEM: The aim of this study was to to compare different intertrochanteric osteotomies for avascular necrosis of the hip and to discuss it in the light of improving results of total hip arthroplasty. METHOD: 106 patients with diagnosis of avascular necrosis of the hip underwent an intertrochanteric osteotomy. During an interval of 14 years a total of 63 flexion osteotomies (partly combined with varisation or valgisation), 29 rotational osteotomies, 13 varisation osteotomies, 8 medializing osteotomies and 2 extension osteotomies were performed. The mean follow-up period for all osteotomies was 69 months (13-180 months). RESULTS: At the time of follow-up investigation, already 75.9% of patients with a rotational osteotomy had received a total hip arthroplasty, comparing to only 34.9% following flexion osteotomy. The Harris Hip Score of the remaining 7 rotational osteotomies was 86.5, for the 41 flexion osteotomies the HHS rated 73.8 points. A high incidence of early complications (55.2%) was seen after rotational osteotomies, compared to 17.5% after flexion osteotomy. For all osteotomies a high correlation between the size of the necrotic area (radiographic ap + axial necrotic sector) and the risk of failure can be demonstrated. Sugioka's rotational osteotomy showed only a very low probability of survival after 5 years (15.9%), in contrast to the flexion osteotomy (5a: 71.6%, 10a: 49.6%). The subgroup of flexion osteotomy with a necrotic sector < 180 degrees achieves the best survival probability of 89.2% after 5 years and 60.7% after 10 years. CONCLUSION: The indication for intertrochanteric osteotomies for avascular necrosis of the hip has to be discussed critically today. Good results can only be expected with small necrotic areas using the flexion osteotomy. It was impossible to obtain satisfactory long-term results with the rotational osteotomy due to a high risk of complications.

Complications in the use of diathermy.

Electrical burns in diathermy rarely occur but are not always recognized as such or thoroughly investigated. The literature has proved to be very sparse in terms of reference to complications, although prolonged courses of treatment are required in individual cases. This paper analyses and discusses the problems of burns associated with diathermy that occurred in seven patients.

[Wartenberg syndrome: a rare or rarely diagnosed compression syndrome of the radial nerve?]. / Wartenberg-Syndrom: Ein seltenes oder selten diagnostiziertes Kompressionssyndrom des N. radialis?

Between August 1993 and June 1995, nine female and one male patient with a neuropathy of the superficial branch of the radial nerve (Wartenberg's syndrome) were treated operatively. Hoffmann-Tinel's sign was positive preoperatively as well as Dellon's test. A modified technique involving longitudinal plication of the brachioradialis tendon was used in seven cases. All patients were free of symptoms six weeks after operation.

[Therapy of meralgia paresthetica with acupuncture. Two case reports]. / Möglichkeit der Behandlung der Meralgia paraesthetica mit Akupunktur. Zwei Fallbeispiele.

The authors demonstrate a way to treat meralgia paresthetica ("jeans disease") with acupuncture. Two patients with therapy-resistant chronic pain and paresthesia of the lateral thigh became free of symptoms quickly and remained under acupuncture therapy. Gynecological, vertebral and urological factors must be excluded before any kind of symptomatic therapy is begun. The advantages and disadvantages of acupuncture are discussed.