PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Bones of Lower Extremity”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Bending moments in lower extremity bones for two standing postures.

The goal of this paper is to study how external gravitational forces stress the lower extremity bones and to ascertain and study how muscle activation compensates for the external load. For these purposes relatively accurate anatomical and biomechanical modelling is necessary. For a comparison of the calculated results to the naturally occurring muscular activity, seven-channel surface EMG activity was recorded. For simplicity a two-dimensional model was developed for the sagittal plane including 19 lower extremity muscles relevant to human standing and walking. In the calculation procedure of muscle forces an optimization procedure is also included. The results give rise to the expected assumption that muscle action is covered by two main requirements: first, to stabilize the joint actively (moment equilibrium) and, second, to compensate efficiently for bending moments produced by gravitational and external forces.

Biomechanical Phenomena↗

Education, employment, insurance, and marital status among 694 survivors of pediatric lower extremity bone tumors: a report from the childhood cancer survivor study.

BACKGROUND: With increasing numbers of childhood cancer survivors, direct sequelae of cancer therapy and psychosocial outcomes are becoming more important. The authors described psychosocial outcomes (education, employment, health insurance, and marriage) for survivors of pediatric lower extremity bone tumors. METHODS: The long-term follow-up study of the Childhood Cancer Survivor Study is a multiinstitutional cohort study comprising 14,054 individuals who have survived for 5 or more years after treatment for cancer diagnosed during childhood or adolescence. Baseline demographic and medical information were obtained. Six hundred ninety-four survivors had osteosarcoma or Ewing sarcoma of the lower extremity or pelvis and were classified by amputation status and by age at diagnosis. The median age at diagnosis was 14 years old with a median of 16 years of follow up since diagnosis. Demographic characteristics were used to analyze the rates of psychosocial outcomes. RESULTS: Amputation status and age at diagnosis did not significantly influence any of the measured psychosocial outcomes. Education was a significant positive predictor of employment, having health insurance, and being currently in their first marriage. Male gender predicted ever being employed and female gender predicted having health insurance and marriage. When compared with siblings, amputees had significant deficits in education, employment, and health insurance. CONCLUSIONS: Overall, no differences between amputees and nonamputees were found. However, gender and education play a prominent role. When compared with siblings, amputees in this cohort may benefit from additional supports.

Adolescent↗

Limb salvage and amputation in survivors of pediatric lower-extremity bone tumors: what are the long-term implications?

The past four decades have seen tremendous progress in the treatment of pediatric and adolescent cancers. As a consequence, there are increasing numbers of adult childhood cancer survivors. This has prompted investigation into the long-term consequences of cancer treatments. One group that merits special study is the survivors of lower-extremity bone tumors. Their function and quality of life may depend in part on both the surgery and the age at which it was performed. Comparisons between studies are difficult because small numbers of patients and the use of varying research designs and methods have limited research in this area. The purpose of this article is to review the major surgical approaches to lower-limb bone tumors and their impact on pediatric patients. The results show that survival is equivalent between amputation and limb salvage. Complications occur more frequently in limb salvage. The long-term outcomes of those undergoing amputation and limb salvage have not been found to be substantially different in regard to quality of life. In conclusion, prospective long-term follow-up of pediatric patients with lower-limb tumors is needed to (1) determine in a uniform manner the long-term complications, quality of life, and functionality of this population and describe differences within this patient population based on age at diagnosis and surgical procedure, (2) identify areas of concern that are amenable to intervention, and (3) provide clinicians and future patients a better understanding of the surgical options.

Adolescent↗

Effects of lateral rotation splinting on lower extremity bone growth: an in vivo study in rabbits.

To study the effect of lateral splinting on limb development, 14 immature rabbit femurs and tibias were marked with six parallel pins. Of these, the lower limbs of seven rabbits were splinted in lateral rotation for 3 weeks (1-year human equivalent). The static position of the foot in the splinted group was 23 degrees more lateral (p greater than 0.05) than in the control group. No significant difference was found in the axial alignment of the pins across the growth plate or diaphyses between the splinted or control groups. This study suggests that night splinting alters the joint relationships and not the shape of the femur or tibia.

Animals↗

Bone grafting. Principles and applications in the lower extremity.

Bone grafting techniques have progressed in the twentieth century, leading to results that are more predictable. A complete understanding of the entire healing process has broadened indications while decreasing complications. Numerous possibilities are available to the foot and ankle surgeon for reconstruction or trauma scenarios. Combining the art (knowing when to use specific grafting techniques) with the science of graft healing will provide satisfactory results.

Animals↗

Comparison of vascularised iliac crest and vascularised fibula transfer for reconstruction of segmental and partial bone defects in long bones of the lower extremity.

The results and complications of lower extremity bone reconstruction using microvascular fibula transfer were retrospectively compared with reconstruction using microvascular iliac crest transfer. Seventeen patients matched as much as possible in regard to location of defect (femur, tibia, ankle) and aetiology (traumatic defect, osteomyelitis) were studied in each group. Data collected included number of prior operative procedures, length of bony defect, presence or absence of associated soft tissue loss, the final clinical and radiographic result, technique of bone immobilisation and duration to union, complications including patency of microvascular anastomoses (if known) and nature and number of additional operative procedures. The outcome of this study suggests that, for reconstruction of the femur or tibia bridging a defect greater than 10 cms, fibula transfer yielded a satisfactory outcome. For defects less than 10 cms resulting from debridement for osteomyelitis, iliac crest transfer yielded a more favourable result. Moreover, the iliac crest appeared to be more optimal than the fibula for reconstruction about the ankle regardless of aetiology.

Bone Remodeling↗

Tissue reaction to implant corrosion in 38 internal fixation devices.

The corrosion characteristics, metallurgical properties, and clinical performance of 38 retrieved internal fixation devices were correlated with the tissue reaction to these devices. Metallurgical parameters included thin and heavy inclusion content, Rockwell hardness, and grain size. The excised fibrous tissue strip was directly overlying each plate at removal and sectioned between screw-hole sites. The material studied from the 38 plates consisted of 201 screw-hole junctions with associated tissue biopsy sites. Clinical histories were obtained on all 38 patients with hardware removal. The average age at the time of plate insertion was 35.6 years (range, 4 to 75 years). Insertion diagnoses included acute trauma (35 patients), joint dislocations (two patients), and fracture nonunion (one patient). The devices included seven upper extremity bone plates, 19 lower extremity bone plates, and 12 hip screw plates. The devices remained in situ an average of 20.4 months (range, 3 to 60 months). Routine asymptomatic removals were performed on 17 of the patients, while the remaining 21 patients were symptomatic at the time of removal. Included in the reasons for symptomatic removal were pain associated with the implant (eight patients), nonunion (four patients), bursae prominence (three patients), and implant breakage (two patients). Significant correlations were found between average tissue reaction scores and average crevice corrosion scores; a trend of increasing average tissue reaction scores with increasing average screw surface corrosion scores also was observed for the 38 devices, although this relationship was not significant. Average crevice corrosion scores and average screw surface corrosion scores were highly correlated for all removals, and for the asymptomatic and symptomatic removal groups. The metallurgical parameters of thin inclusion content and heavy inclusion content also were significantly correlated for all removals, as well as for symptomatic removals. Similarly, significant correlations were found between the individual tissue reaction scores and crevice corrosion scores from the 201 individual sites, again for all devices and for the asymptomatic and symptomatic removal groups. Tissue reaction scores and time in situ showed significant correlation, with tissue reaction decreasing over time. Crevice corrosion and screw surface corrosion scores were not significantly related to time in situ. The results of this study indicate that there is considerable tissue reaction to the corrosion products of this material.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

The use of vacuum-assisted closure therapy for the treatment of lower-extremity wounds with exposed bone.

Lower-extremity wounds with exposed tendon, bone, or orthopedic hardware present a difficult treatment challenge. In this series of patients, subatmospheric pressure therapy was applied to such lower-extremity wounds. Seventy-five patients with lower-extremity wounds, most of which were the result of trauma, were selected for this study. Dressings made of sterile open-cell foam with embedded fenestrated tubing were contoured to the wound size and placed into the wound. The site was covered with an adhesive plastic sheet. The sheet was placed beneath any external fixation devices, or the fixation device was enclosed within the sheet. The tubing was connected to the vacuum-assisted closure pump. Continuous subatmospheric suction pressure (125 mmHg) was applied to the wound site. The wounds were inspected and the dressings were changed every 48 hours.Vacuum-assisted closure therapy greatly reduced the amount of tissue edema, diminishing the circumference of the extremity and thus decreasing the surface area of the wound. Profuse granulation tissue formed rapidly, covering bone and hardware. The wounds were closed primarily and covered with split-thickness skin grafts, or a regional flap was rotated into the granulating bed to fill the defect. Successful coverage was obtained without complication in 71 of 75 patients. Wounds have been stable from 6 months up to 6 years.

Bandages↗

Reamed versus nonreamed intramedullary nailing of lower extremity long bone fractures: a systematic overview and meta-analysis.

OBJECTIVE: To determine the effect of reamed versus nonreamed intramedullary (IM) nailing of lower extremity long bone fractures on the rates of nonunion, implant failure, malunion, compartment syndrome, pulmonary embolus, and infection. DESIGN: Quantitative systematic review of prospective, randomized controlled trials. DATA IDENTIFICATION: MEDLINE and SCISEARCH computer searches provided lists of published randomized clinical trials from 1969 to 1998. Extensive hand searches of major orthopaedic journals, bibliographies of major orthopaedic texts, and personal files identified additional studies. STUDY SELECTION AND DATA EXTRACTION: Of 676 citations initially identified, sixty proved potentially eligible, of which four published and five unpublished randomized trials met all eligibility criteria. Each of three investigators assessed study quality and abstracted relevant data. RESULTS: The pooled relative risk of reamed versus nonreamed nails (nine trials, n = 646 patients) was 0.33 [95% confidence interval (CI), 0.16 to 0.68; p = 0.004]. The absolute risk difference in nonunion rates with reamed IM nailing was 7.0 percent (95% CI, 1 to 11 percent). Thus, one nonunion could be prevented for every fourteen patients treated with reamed IM nailing [number needed to treat (NNT) = 14.28]. The risk ratios for secondary outcome measures were: implant failure, 0.30 (95% CI, 0.16 to 0.58; p < 0.001); malunion, 1.06 (95% CI, 0.32 to 3.57); pulmonary embolus, 1.10 (95% CI, 0.26 to 4.76); compartment syndrome, 0.45 (95% CI, 0.13 to 1.56); and infection, 0.98 (95% CI, 0.21 to 4.76). Sensitivity analyses suggested that reported rates of nonunion and implant failure were higher in studies of lower quality. The type of long bone fractured (tibia or femur), the degree of soft tissue injury (open or closed), study quality, and whether a study was published or unpublished did not significantly alter the relative risk of nonunion between reamed and nonreamed IM nailing. CONCLUSIONS: There is evidence from a pooled analysis of randomized trials that reamed IM nailing of lower extremity long bone fractures significantly reduces rates of nonunion and implant failure in comparison with nonreamed nailing.

Bone Nails↗

Techniques for harvesting autogenous bone graft of the lower extremity.

Autogenous bone grafts have several advantages over allogenic bone grafts, especially when being used for arthrodesis or for revision of malunions or nonunions. Procurement of these grafts can come from remote regions or from areas adjacent to the operative site. The lower extremity provides a source for obtaining cortical, corticocancellous, and cancellous bone for use in foot and ankle surgery. Harvesting techniques do not come without complications and the necessity for proper techniques in handling is crucial.

Ankle↗

[Non-traditional procedure of revascularization of the lower extremities with bone transplants in unreconstructable arterial occlusions].

An unusual method for salvation of lower extremities with critical ischemia is described. A free bone fragment is formed by osteotomy and distracted by an osteotomy device during a period of 31 to 36 days with subsequent fixation (during a total of 45 to 60 days). This treatment is usually combined with lumbar sympathectomy. This procedure intends a stimulation of the peripheral circulation. It was used in 92 patients with non-reconstructable distal arterial occlusions in stage III and IV. In spite of some complications and failures the extremity could be saved in 77% of the cases. Controls over 2 to 36 months in 67 patients revealed a favourable result lasting over one year in 43 of the cases.

Adult↗

Scintigraphy of lower extremity cadaveric bone allografts in osteosarcoma patients.

PURPOSE: To describe scintigraphic characteristics of bone allografts used in limb salvage reconstruction after resection of lower extremity osteosarcoma. MATERIALS AND METHODS: The authors reviewed 85 skeletal scintigrams of 20 pediatric patients followed up for 0.5-5.7 years after resection of lower extremity osteosarcoma and allograft reconstruction. Uptake in the allograft and adjacent host tissues was assessed visually. RESULTS: Lack of tracer uptake in the allografts was seen in 99% of the studies and a faint rim of tracer localization outlining the allograft's periphery was seen in 95% of the studies. Increased uptake was noted at the allograft-host bone junction in 78% of the studies. Uptake was increased in the joint surfaces of native bones articulating with allografts (97% of studies), including the patella (93% of studies) when the knee was involved. These findings were stabilized as time passed. CONCLUSION: Cadaveric bone allografts have a characteristic scintigraphic appearance in this selected patient group that reflects the physiology of their incorporation process.

Adolescent↗

[Stress tolerance of patients following fractures of the lower extremities].

In bone fractures in the lower extremities a high blood loss must be taken into consideration. An adequate blood transfusion should be given before and during diagnostic procedures. Diagnostic measures should proceed quickly and be limited to the necessary treatment. Operative setting of closed fractures can be programmed when conditions are optimal. Immediate setting of open fractures has proven to be valuable not only because the blood loss may be controlled, but also because extensive soft tissue distraction and possible infection can be prevented. The crush-syndrome can be caused by crushing injuries, pluck-out injuries and traumatic amputation and endanger the patient's life.

Fracture Fixation, Internal↗