bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutual associations among microstructural, physical and mechanical properties of human cancellous bone
Authors: Ding M. , Odgaard A. , Danielsen C. C. , Hvid I. 
Published: February 2018

Previous studies have shown that low-density, rod-like trabecular structures develop in regions of low stress, whereas high-density, plate-like trabecular structures are found in regions of high stress. This phenomenon suggests that there may be a close relationship between the type of trabecular structure and mechanical properties. In this study, 160 cancellous bone specimens were produced from 40 normal human tibiae aged from 16 to 85 years at post-mortem. The specimens underwent micro-CT and the microstructural properties were calculated using unbiased three-dimensional methods. The specimens were tested to determine the mechanical properties and the physical/compositional properties were evaluated. The type of structure together with anisotropy correlated well with Young’s modulus of human tibial cancellous bone. The plate-like structure reflected high mechanical stress and the rod-like structure low mechanical stress. There was a strong correlation between the type of trabecular structure and the bone-volume fraction. The most effective microstructural properties for predicting the mechanical properties of cancellous bone seem to differ with age.
Bone ingrowth in the presence of particulate polyethylene
Authors: Bechtold J. E. , Kubic V. , Søballe K. 
Published: February 2018

We have investigated whether the presence of polyethylene (PE) alone is sufficient to cause an aggressive periprosthetic tissue response, or whether certain mechanical interface conditions can allow bone to grow while in the presence of PE. An experimental implant was loaded in the presence and absence of particulate PE under stable and unstable conditions. Bone with a thin, discontinuous fibrous membrane formed in both groups of stable implants, either in the presence or absence of PE. By contrast, a continuous fibrous membrane consistently formed in both groups of unstable implants. The membrane consisted of loose fibrous connective tissue when PE was absent, and dense connective tissue with macrophages and a synovial lining when PE was present. In this model, if the interface was stable, the presence of PE was not sufficient to prevent the formation of bone or to produce a phagocytic tissue response. Only when the interface was unstable did a fibrous membrane form, and only then in the presence of PE.
Effects of alumina and zirconium dioxide particles on arachidonic acid metabolism and proinflammatory interleukin production in osteoarthritis and rheumatoid synovial cells
Authors: Liagre B. , Moalic S. , Vergne P. , Charissoux J. L. , Bernache-Assollant D. , Beneytout J. L. 
Published: February 2018

We describe a model which can be used for in vitro biocompatibility assays of biomaterials. We studied the in vitro response of human osteoarthritis or rheumatoid arthritis fibroblast-like synoviocytes to Al2O3 or ZrO2 particles by analyzing the production of interleukin-1 (IL-1) and interleukin-6 (IL-6) and the metabolism of arachidonic acid via lipoxygenase and cyclo-oxygenase pathways. Our results show that, in these cells and under our experimental conditions, Al2O3 and ZrO2 did not significantly modify the synthesis of IL-1 and IL-6 or the metabolism of arachidonic acid.
Subacromial decompression
Authors: Massoud S. N. , Levy O. , Copeland S. A. 
Published: February 2018

We report the results of arthroscopic subacromial decompression and debridement of the rotator cuff for chronic small- and medium-sized tears in 114 patients (118 shoulders) between two and five years after surgery. The mean Constant score was improved to 69.8, and 88 shoulders (74.6%) had a satisfactory outcome. Of patients under the age of 60 years the outcome was satisfactory in 59.3%, and in those over 60 years, in 87.5% (p < 0.001). An unsatisfactory outcome was related to manual work (p < 0.001) and a duration of symptoms of more than 12 months (p < 0.05). The outcome was not related to the size of the tear, the muscles involved or biceps pathology. Further surgery was required in 25 patients after a mean of 13.7 months (3 to 35); ten tears had progressed in size, but none became irreparable. There was no relationship between the increase in the size of the tear and its initial size, the muscles involved or the presence of biceps pathology. No tear became smaller with time.
The intramedullary elongation nail for femoral lengthening
Authors: García-Cimbrelo E. , de la Mano A. Curto , García-Rey E. , Cordero J. , Marti-Ciruelos R. 
Published: February 2018

We have analysedin the results of 24 femoral lengthenings in 23 patients operated on between 1993 and 2000, using a gradual elongation intramedullary nail (Albizzia). Of the 23 patients, 22 had femoral deficiency and one was of short stature. Their mean age was 16.9 years. Technical difficulties encountered during the procedure were mild or moderate in 18 femora and severe in six femora. Distraction was obtained by 15 ratchetings per day (1 mm/day). There were 18 excellent results although in two patients this was achieved after the development of a pseudarthrosis which required further surgery. There were four good and two fair results in which the lengthening obtained was at least 3 cm less than had been projected. The consolidation index was 35.2 days/cm. No patient had associated long-term stiffness of the knee. Femoral lengthening using an elongation nail gives good results and is a comfortable procedure.
Hemicortical allograft reconstruction after resection of low-grade malignant bone tumours
Authors: Deijkers R. L. M. , Bloem R. M. , Hogendoorn P. C. W. , Verlaan J. J. , Kroon H. M. , Taminiau A. H. M. 
Published: February 2018

Low-grade surface tumours of bone may theoretically be treated by hemicortical resection, retaining part of the circumference of the cortex. An inlay allograft may be used to reconstruct the defect. Since 1988 we have performed 22 hemicortical procedures in selected patients with low-grade parosteal osteosarcoma (6), peripheral chondrosarcoma (6) and adamantinoma (10). Restricted medullary involvement was not a contraindication for this procedure. There was no evidence of local recurrence or distant metastasis at a mean follow-up of 64 months (27 to 135). Wide resection margins were obtained in 19 patients. All allografts incorporated completely and there were no fractures or infections. Fractures of the remaining hemicortex occurred in six patients and were managed successfully by casts or by osteosynthesis. The functional results were excellent or good in all except one patient. Hemicortical procedures for selected cases of low-grade surface tumours give excellent oncological and functional outcomes. There was complete remodelling and fewer complications when compared with larger intercalary procedures. The surgery is technically demanding but gives good clinical results.
Efficacy of prenatal ultrasonography in confirmed club foot
Authors: Keret D. , Ezra E. , Lokiec F. , Hayek S. , Segev E. , Wientroub S 
Published: February 2018

Club foot can be diagnosed by ultrasound of the fetus in more than 60% of cases. We have correlated the accuracy of the prenatal findings in 281 ultrasound surveys with the physical findings after birth and the subsequent treatment in 147 children who were born with club foot. The earliest week of gestation in which the condition was diagnosed with a high degree of confidence was the 12th and the latest was the 32nd. Not all patients were diagnosed at an early stage. In 29% of fetuses the first ultrasound examination failed to detect the deformity which subsequently became obvious at a later examination. Club foot was diagnosed between 12 and 23 weeks of gestation in 86% of children and between 24 and 32 weeks of gestation in the remaining 14%. Therefore it can be considered to be an early event in gestation (45% identified by the 17th week), a late event (45% detected between 18th and 24th weeks) or a very late event (10% recognised between 25th and 32nd weeks). We cannot exclude, however, the possibility that the late-onset groups may have been diagnosed late because earlier scans were false-negative results. The prenatal ultrasonographic findings were correlated with the physical findings after birth and showed that bilateral involvement was more common than unilateral. There was no significant relationship between the prenatal diagnosis and the postnatal therapeutic approach (i.e., conservative or surgical), or the degree of rigidity of the affected foot.
Antibiotic prophylaxis in surgery of the intervertebral disc
Authors: Tai C. C. , Want S. , Quraishi N. A. , Batten J. , Kalra M. , Hughes S. P. F. 
Published: February 2018

Antibiotics are often administrated prophylactically in spinal procedures to reduce the risk of infection of the disc space. It is still not known which antibiotics are able to penetrate the intervertebral disc effectively. In a prospective, randomised, double-blind clinical study, we examined the penetration of the intervertebral discs of two commonly used antibiotics, cefuroxime and gentamicin. The patients, randomised into two groups, received either 1.5 g of cefuroxime or 5 mg/kg of gentamicin prophylactically two hours before their intervertebral discs were removed. A specimen of blood, from which serum antibiotic levels were determined, was obtained at the time of discectomy. Therapeutic levels of antibiotic were detectable in the intervertebral discs of the ten patients who received gentamicin. Only two of the ten patients (20%) who received cefuroxime had a quantifiable level of antibiotic in their discs although therapeutic serum levels of cefuroxime were found in all ten patients. Our results show that cefuroxime does not diffuse into human intervertebral discs as readily as gentamicin. It is possible that the charge due to ionisable groups on the antibiotics can influence the penetration of the antibiotics. We therefore recommend the use of gentamicin in a single prophylactic dose for all spinal procedures in order to reduce the risk of discitis.
Recovery of motor deficits after microdiscectomy for lumbar disc herniation
Authors: Postacchini F. , Giannicola G. , Cinotti G. 
Published: February 2018

We have studied, prospectively, 116 patients with motor deficits associated with herniation of a lumbar disc who underwent microdiscectomy. They were studied during the first six months and at a mean of 6.4 years after surgery. Before operation, muscle weakness was mild (grade 4) in 67% of patients, severe (grade 3) in 21% and very severe (grade 2 or 1) in 12%. The muscle which most frequently had severe or very severe weakness was extensor hallucis longus, followed in order by triceps surae, extensor digitorum communis, tibialis anterior, and others. At the latest follow-up examination, 76% of patients had complete recovery of strength. Persistent weakness was found in 16% of patients who had had a mild preoperative deficit and in 39% of those with severe or very severe weakness. Muscle strength was graded 4 in all patients with persistent weakness, except for four with a very severe preoperative deficit affecting the L5 or S1 nerve root. They showed no significant recovery. Excluding this last group, the degree of recovery of motor function was inversely related to the preoperative severity and duration of muscle weakness. The patients’ subjective functional capacity was not directly related to the degree of recovery except in those with persistent severe or very severe deficit.
Early versus late mobilisation after simple excision of the trapezium
Authors: Horlock N. , Belcher H. J. C. R. 
Published: February 2018

We randomly selected 39 patients undergoing excision of the trapezium for osteoarthritis of the first carpometacarpal joint into two groups, with mobilisation either at one or at four weeks after operation. The patients were reviewed at a median of six months (6 to 8). The clinical details, the severity of the disease and the preoperative clinical measurements of both groups were similar. Excision of the trapezium resulted in significant improvement in objective and subjective function. Comparison of the outcomes of the two groups showed no differences except that patients found early mobilisation significantly more convenient. Although there was no significant difference in the range of movement between the groups, there was a small loss of movement at the metacarpophalangeal joint in the late mobilisation group. Our findings show that simple excision of the trapezium is an effective procedure for patients with carpometacarpal osteoarthritis of the thumb and that prolonged splintage is neither necessary nor desirable.
Surgical techniques for reconstruction of chronic insufficiency of the triceps
Authors: Sanchez-Sotelo J. , Morrey B. F. 
Published: February 2018

Seven patients with chronic insufficiency of the triceps were treated by either a rotation flap using anconeus (4) or an allograft of tendo Achillis (3). The latter procedure was selected for patients with a large defect in whom the anconeus muscle had been devitalised. Five disruptions were in patients who had previously undergone an elbow replacement. The patients were assessed for subjective satisfaction, pain, range of movement and strength, and the results were graded using the Mayo Elbow Performance Score (MEPS). The mean follow-up was for 33 months (9 to 63). One rotation flap failed six months after operation. At the most recent follow-up, the remaining six patients had no or slight pain, restoration of a functional arc of movement and normal or slightly decreased power of extension. All six were satisfied with the outcome and were able to resume their daily activities with no limitations other than those imposed by the previous elbow replacement. The final MEPS was 100 points in five patients and 75 in one.
Application of locked intramedullary nails in the treatment of complications after distraction osteogenesis
Authors: Lai K.-A. , Lin C.-J. , Chen J.-H. 
Published: February 2018

Distraction osteogenesis (callotasis) has been widely used in patients with limb-length inequality or massive bone defects. This procedure, however, may be associated with a high incidence of physical and psychosocial complications. Callotasis telescoping on a locked intramedullary nail has been used to shorten the period of external fixation. Little attention has been given to the use of locked intramedullary nails in the treatment of complications after callotasis. Between 1990 and 1999, we used locked intramedullary nailing in 27 patients for the treatment of complications after distraction osteogenesis. There were 17 men and ten women with a mean age of 33.2 years (16 to 66). The nail was inserted at a mean of 3.4 weeks (0 to 15) after removal of the external fixator. Simultaneous autogenous bone grafting and soft-tissue reconstruction were also undertaken in seven and two patients, respectively. There was consolidation of the callus or docking site in all patients at a mean of 6.4 months (2 to 14) after surgery. The mean shortening of the callus was 0.7 cm (0 to 2.5). Two patients had infection at the site of a distal screw which resolved after removal of the nail. In 17 patients the nail was removed at a mean of 26 months after its insertion. Locked intramedullary nails are useful in treating complications after distraction osteogenesis in skeletally mature patients. The risk of infection should be borne in mind.
The influence of surface roughness on stem-cement gaps
Authors: Race A. , Miller M. A. , Ayers D. C. , Cleary R. J. , Mann K. A. 
Published: February 2018

We have compared the interface morphology at the stem-cement interface of standard Charnley stems with a satin finish (Ra = 0.75 μm) with identical stems which had been grit-blasted over their proximal third (Ra = 5.3 μm) to promote a proximal bond. The stems were cemented into cadaver femora using conventional contemporary cementing techniques. After transverse sectioning, we determined the percentage of the perimeter of the stem which had a gap at the interface. There were substantial gaps (mean 31.4 ± 17.1%) at the stem-cement interface in the grit-blasted region. This fraction was significantly (paired t-test, p = 0.0054) higher than that found around the contralateral satin-finished stems (mean 7.7 ± 11.7%). Although studies of isolated metal-cement interfaces have shown that the bond strength can increase with surface roughness it cannot be assumed that this effect will be observed under clinical conditions.
The relationship between the strength of supination of the forearm and rotation of the shoulder
Authors: Savva N. , McAllen C. J. P. , Giddins G. E. B. 
Published: February 2018

In children with obstetric brachial plexus palsy (OBPP) who develop an internal rotation deformity of the shoulder, release of subscapularis improves the range of external rotation of the shoulder and the strength of supination of the forearm. We studied the strength of supination in 35 healthy adult volunteers at 45° of both internal and external rotation. The mean and maximum torques were greater in external than internal rotation by 8.7% and 7.5%, respectively. This was highly significant (p < 0.0001). The increased strength of supination in external rotation is probably because the maximum power of biceps, particularly the long head, may be exerted in this position. In children the difference may be even greater due to anatomical differences causing the dramatic increases in the strength of supination after surgery for OBPP. In adults our findings suggest that the supination exercises which are undertaken after injury or surgery to the forearm or wrist should be performed in external rotation.
Cement particles containing radio-opacifiers stimulate pro-osteolytic cytokine production from a human monocytic cell line
Authors: Shardlow D. L. , Stone M. H. , Ingham E. , Fisher J. 
Published: February 2018

Proponents of the biological theory of aseptic loosening have in recent years tended to concentrate on the production and distribution of particulate ultra-high-molecular-weight polyethylene (UHMWPE) debris around the potential joint space. However, mechanical loading of cemented implants with the differing elastic moduli of metal stems, polymethylmethacrylate (PMMA) cement and bone can result in relative micromotion, implying the potential for production of metal and PMMA particles from the stem-cement interface by fretting wear. In order to investigate the production and biological reactivity of debris from this interface, PMMA and metal particulate debris was produced by sliding wear of PMMA pins containing barium sulphate and zirconium dioxide against a Vaquasheened stainless steel counterface. This debris was characterised by SEM, energy-dispersive analysis by X-ray (EDAX) and image analysis, then added to cell cultures of a human monocytic cell line, U937, and stimulation of pro-osteolytic cytokines measured by ELISA. Large quantities of PMMA cement debris were generated by the sliding wear of PMMA pins against Vaquasheened stainless steel plates in the method developed for this study. Both cements stimulated the release of pro-osteolytic TNFα from the U937 monocytic cell line, in a dose-dependent fashion. There was a trend towards greater TNFα release with Palacos cement than CMW cement at the same dose. Palacos particles also caused significant release of IL-6, another pro-osteolytic cytokine, while CMW did not. The particulate cement debris produced did not stimulate the release of GM-CSF or IL1β from the U937 cells. These results may explain the cytokine pathway responsible for bone resorption caused by particulate PMMA debris. Radio-opaque additives are of value in surgical practice and clinical studies to quantify the relevance of these in vitro findings are required before the use of cement containing radio-opacifier is constrained.
Long-term results of patellofemoral arthroplasty
Authors: Kooijman H. J. , Driessen A. P. P. M. , van Horn J. R 
Published: February 2018

We studied retrospectively the outcome of patellofemoral arthroplasty (PFA) using the Richards prosthesis in 51 patients (56 knees). Their mean age was 50 years (30 to 77). In 43 patients (45 knees), the American Knee Society score and the patients’ subjective judgement were assessed. Excellent or good results were obtained in 86% of cases at a mean follow-up of 17 years (15 to 21). Because of ongoing tibiofemoral osteoarthritis, two patients required a high tibial osteotomy and ten PFAs were converted to a total knee arthroplasty after a mean of 15.6 years (10 to 21). The PFAs were stable during follow-up with a loosening rate of only 2%. We conclude that a patellofemoral prosthesis is a good treatment option with successful long-term results in middle-aged patients with radiologically documented, isolated, patellofemoral osteoarthritis.
Treatment of recurrence of symptoms after excision of an interdigital neuroma
Authors: Stamatis E. D. , Myerson M. S. 
Published: February 2018

During a six-year period (January 1996 to January 2002 ), we re-explored 60 interspaces (49 patients, 49 feet) for recurrence or persistent symptoms after one or more previous procedures for excision of an interdigital neuroma. Ten patients underwent concomitant excision of a primary neuroma from an adjacent interspace, and 19 underwent concomitant forefoot surgery. The mean follow-up was 39.7 months (6 to 79). Evaluation included review of records and radiographs, clinical assessment, and a questionnaire regarding satisfaction, pain, restriction of footwear and activity. In total, 15 patients (30.7%) were completely satisfied, 13 (26.5%) were satisfied with minor reservations, ten (20.4%) were satisfied with major reservations and 11 (22.4%) were dissatisfied with the outcome. Of the 49 patients, 28 (57.2%) had no or mild pain, 29 (59.2%) had moderate or severe restriction of footwear and eight (16.3%) had moderate restriction of activity. Intra-operative findings, simultaneous surgery to adjacent interspaces, concomitant forefoot surgery and previous re-explorations did not significantly influence the outcome. Persistent or recurrent symptoms after transection of a nerve present a challenging problem for both the surgeon and patient. It is essential that there is a thorough pre-operative discussion with the patient, providing the rates of failure and the increased likelihood of restriction of footwear and activity after revision surgery.