Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LEG LENGTHENING”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 253 records · Page 14Linked to original sources
PubMed1996

[Contribution of Ilizarov's equipment in the treatment of congenital pseudarthrosis of the lower limb].

INTRODUCTION: Risks and benefits of using Ilizarov apparatus in the treatment of congenital tibial or fibular pseudarthrosis (CTFP) are presented in this retrospective study. MATERIALS AND METHODS: We reviewed with an average follow-up of 3 years and 4 months, the outcome of twenty consecutive patients treated between 1985 and 1993, for a CTFP using the Ilizarov apparatus. Sixteen patients were treated for non union of both tibia and fibula, 1 patient for an isolated non union of the fibula, and 3 patients for correction of a previously treated, malunited pseudarthrosis. The apparatus was used in four different ways: Realignement, end to end compression, and leg lengthening in 14 cases, Simple external fixation in association with another method of treatment in 2 cases, Progressive correction of malunion in 3 cases, Progressive diaphyseal reconstruction in 1 case (fibula). RESULTS: The mean fixation duration was 7.3 months. Union was achieved with the initial treatment in 11 out of 20 cases (including the 3 cases of malunion correction). Bone grafting was used in 7 out of the 9 remaining cases, and led to bone healing in 3 of them. Five complications were encountered: deep infection in 1 case, repeated stress fracture in 1 case, repeated fracture of the pins in 1 case, malunion in 6 cases, and less than 3 cm leg length discrepancy in 4 cases. DISCUSSION: Ilizarov external fixator is an efficient solution for many cases of CTFP, in which healing did not occur with other methods of treatment. The best indication for its use are the normotrophic and the hypertrophic types of non union (Apoil II), after the age of 4 or 5. Secondary massive bone grafting is to be considered in some cases, since it can either achieve bone union or strengthen it. The major disadvantage of this method is the lack of excision of the dystrophic tissue at the non union site. So, even after the non union is healed, the bone remains dystrophic and fragile, and necessitates a permanente protective orthosis, until the end of bone growth.

Adolescent↗
PubMed2006

Balance lower limb loads and 3D spine modifications after total hip joint replacement: effects of leg length discrepancy correction.

Following total hip joint replacement (THJR), the durability of a prosthesis is limited by: wearing of frictional surfaces and loosening and migration of the prosthesis-cement-bone system. Literature review witnesses biomechanical studies focused mainly/only on hip functional state while none of them approached leg length discrepancy (LLD), posture unbalancing or spine related problems after THJR. Conversely, these latter could be critical elements for surgery and rehabilitation success, given the possible induction of asymmetric loading patterns. This study presents the results obtained by using a recently proposed methodology, to measure 3D subject posture balance and spine morphology and to evaluate its usefulness in individual therapy tuning/follow up. 3D subject's posture has been measured by means of 3D opto-electronic device, force platform and baropodography. 90 subjects after THJR have been included in this study. The subjects have been evaluated in two different epochs: 3 weeks after surgical intervention and after 3 months. 77/90 patients presented a LLD, pelvic obliquity and posture unbalancing. More than 90% of this group showed an overall postural re-balancing induced by the use of simple underfoot wedge. 70/77 patients needed wedge under the healthy side showing the surgical intervention produced a leg lengthening. 60/90 (52 LLD) patients underwent up to now to control and patients who wore the suggested wedge (63.4%) presented an improvement over all the considered quantitative parameters. Patients who wore a shorter than suggested wedge (23.1%), or that did not wear the suggested wedge (13.5%) presented a moderate or significant worsening of their postural balancing respectively.

Adult↗
PubMed1984

[Tibial lengthening using Judet's method. Apropos of 108 cases in children].

One hundred and eight tibial lengthenings were performed in 106 children using the technique and apparatus of R. and J. Judet. The average lengthening obtained was 43,7 mm with a maximum of 60 mm. In some cases, repeated lengthening obtained 98 mm. Bone union was sound after an average of 4 months. It took 5 months in 13 cases, and a secondary graft was necessary in only 5 cases. Only one non-union occurred, due to infection. It seems that the results obtained with this technique were better than those obtained after internal fixation following removal of the distractor. In 5 instances vascular impairment was seen with recovery in 3 cases, but necrosis of a toe and of the tibialis posterior muscle in 2 cases. In 17 instances neurological impairment was seen with 2 showing persistent anaesthesia and one a paralysis of the extensor hallucis longus. However mild neurological impairment was more frequent than was initially expected. In some cases, preexisting knee deformities were aggravated by the leg lengthening. Some deformities at the site of the lengthening were related to an incorrect position of the distractor or to a contracture of soft tissues. It may also be made worse by non-union of the fibula. These deformities may react on the ankle or the foot and may continue to worsen after the completion of lengthening due to subsequent disturbance of growth in 15 p. 100 of cases.

Adolescent↗
PubMed1998

Distraction osteogenesis in craniofacial surgery: a review.

Distraction osteogenesis is a technique of new bone formation by the gradual separation of bony fragments. The method, although initially developed for limb lengthening, is now being applied in the treatment of craniofacial deformities. A number of principles have been established through careful scientific study to guide clinical practice, such as the ideal rate and rhythm of distraction, the need for periosteal preservation during bone division, a "latent period" of neutral fixation before, and a "consolidation period" after distraction. The technique is being applied in craniofacial surgery particularly for mandibular deformities and offers considerable advantages over previous methods such as osteotomy and inlay bone grafting. Donor site morbidity is avoided, the investing soft tissue envelope is concurrently expanded, and the magnitude of the procedure is less. However, the technique is still in its infancy and requires further modification and refinement before widespread acceptance as a treatment in mainstream craniofacial surgery. Problems with cutaneous scarring and socially undesirable external hardware, particularly in the pediatric population, have led to the emergence of intraoral miniature devices, with the ultimate goal of development of a multiplanar internal autodistractor. Furthermore, many principles well established in leg lengthening, such as the rate and rhythm of distraction, need to be reexamined and the parameters redefined with particular reference to the craniofacial skeleton. Distraction osteogenesis has an expanding role in craniofacial surgery.

Animals↗
PubMed1989

[Entrapment of the synovium of the hip joint in children: a report of 15 cases].

15 cases, aged 4 to 14 years, experienced, a few days after a mild trauma, slight pain and limited motion of hip joint with the corresponding leg lengthened, a result of restrained adduction. Plane X-ray films of these hip joints showed nothing wrong, yet arthrography done on 4 cases and operative exploration in 1 patient found that a portion of synovium at the anteromedio-inferior part of the hip had been entrapped into the joint, on account of which the term entrapment of synovium of hip joint is coined. Under general anesthesia, gentle manipulation resulted in immediate relief in all hips but one, which failed to respond and then under went open operation, a very good chance of looking into the matter: a big portion of synovium incarcerated in the joint, the actual offender. There has been no recurrence found up to the time of writing. The pathogenesis and the related differential diagnosis have been discussed in detail.

Adolescent↗
PubMed1992

The microstructural tensile properties and biochemical composition of the bovine distal femoral growth plate.

The tensile properties of distal femoral growth plates from 12-month-old cows were determined on uniformly prepared straight bone-growth plate-bone specimens (7 x 7 mm2 in cross-section) from predetermined anatomical sites on the physis. Each specimen was distracted to failure using a computer-controlled servo-hydraulic testing machine at a strain rate of 0.004 s-1. It was found that the exponential constitutive law, using finite deformation formulation for strain, provides an excellent description of the stress-strain behavior of all the specimens up to the point of failure. The ultimate stress and both tangent moduli (i.e., the toe region tangent modulus and the tangent modulus calculated at 75% of ultimate strain) varied with anatomical site. The anterior region was the strongest, followed by the posterior/lateral. The anterior and posterior/lateral regions were also the stiffest, whereas the posterior/medial and center regions were the weakest and most compliant. The bone-growth plate-bone specimen exhibited a low ultimate strain (13.8% +/- 6%) that did not vary significantly throughout the growth plate. This result suggests that disruption of the physis may occur in vivo even at the lower distractions currently recommended for the clinical chondrodiatasis procedure for leg lengthening. The biochemical composition of the growth plate in the anatomical regions correlated well with the tensile properties. There was a greater collagen content in the regions that were the stiffest and strongest. The gross morphology of the growth plate of the bovine distal femur is also described in this study. There is a regular pattern to the undulations of the physis at several dimensional levels. Histologic findings showed that orientation of the hypertrophic cell columns and transphyseal septa are aligned nearly parallel to the longitudinal axis of the diaphyseal shaft. This column orientation is not affected by the undulation of the primary contour of the physis, which at certain locations may be inclined as much as 60 degrees relative to the diaphyseal axis. The orientation of the hypertrophic cell columns appears to be one of the dominant microstructural features influencing the tensile behavior of the bone-growth plate-bone specimens.

Animals↗
PubMed2000

Tissues formed during distraction osteogenesis in the rabbit are determined by the distraction rate: localization of the cells that express the mRNAs and the distribution of types I and II collagens.

An experimental model of leg lengthening was used to study the morphology of, the collagenous proteins present, and the collagen genes expressed in the regenerating tissue following 20% lengthening at four different distraction rates. At a distraction rate of 0.3 mm/day (8 weeks distraction), the regenerate consists of intramembranous bone and localized areas of fibrocartilage. At rates of 0.7 (4 weeks) and 1.3 mm/day (2 weeks), the bone that grows from the cut ends of the cortical bone is separated by fibrous tissue and cartilage is present. At 2.7 mm/day (1 week), only fibrous tissue and sparse bone are present. Type I collagen is present in the matrices around the cells expressing its mRNA and similarly, type II collagen is located around the chondrocytes. Type I collagen mRNA is expressed predominantly by the fibroblasts in the fibrous tissue, the bone surface cells and to a reduced extent by the osteocytes. Type II collagen mRNA is expressed by chondrocytes. The results suggest that osteoblasts and chondrocytes within the regenerate originate from the same pool of progenitor cells, and the differentiation of these cells and the expression of types I and II collagen genes are altered by different rates of distraction. These observations suggest that the optimal rate of distraction in the model is 0.7 mm/day.

Animals↗
PubMed1992

Osteofibrous dysplasia of the tibia treated by bracing.

Osteofibrous dysplasia of the tibia in children will commonly recur after surgical resection. The use of a leg brace until puberty offers a useful method of conservative management. Seven female patients, age three months to nine years at the time of brace treatment, have been followed for 3.5 to 18 years, an average of nine years, with evidence of satisfactory healing of the lesions in all. Three of the cases had recurred after surgery, two with fibular grafts and one required leg lengthening. The use of a brace to control bowing of the tibia while awaiting spontaneous regression is advised until epiphyseal closure.

Braces↗
PubMed2005

Application of micro-CT assessment of 3-D bone microstructure in preclinical and clinical studies.

As the mechanical competence of trabecular bone is a function of its apparent density and 3-D distribution, assessment of 3-D trabecular structural characteristics may improve our ability to understand the pathophysiology of osteoporosis, to test the efficacy of pharmaceutical intervention, and to estimate bone biomechanical properties. We have studied ovariectomy-induced osteopenia in rats and its treatment with agents such as estrogen and sodium fluoride. We have demonstrated that 3-D micro-computed tomography (microCT) can directly quantify mouse trabecular and cortical bone structure with an isotropic resolution of 6 microm(3). MicroCT is also useful for studying osteoporosis in mice and phenotypes of mice with gene manipulation, such as SHIP-knockout mice, which are severely osteoporotic due to increased numbers of hyperresorptive osteoclasts, PTHrP heterozygous-null mice, and mice with Zmpste24 deficiency. MicroCT can quantify osteogenesis in mouse Ilizarov leg-lengthening procedures, osteoconduction in a rat cranial defect model, and structural changes in arthritic rabbits, rats, and mice. In clinical studies, we evaluated longitudinal changes in the iliac crests. Paired bone biopsies from the same premenopausal and postmenopausal women showed the changes in 3-D trabecular structure, such as decreased trabecular thickness, shifting of trabecular model from platelike structure to rodlike structure, and decreased degree of anisotropy were remarkable. Treatment with PTH in postmenopausal women with osteoporosis significantly improved trabecular morphology with a shift toward a more platelike structure, increased trabecular connectivity density, and increased cortical thickness. Paired bone biopsy specimens from the iliac crest in postmenopausal women with osteoporosis before and an average of 2 years after beginning of estrogen replacement therapy demonstrated that posttreatment biopsies showed a significant change in the ratio of plates to rods and statistically insignificant changes in other 3-D trabecular parameters. Thus, microCT can characterize 3-D structure of various animal models, and the longitudinal changes in 3-D bone microarchitectural integrity that deteriorates in the transmenopausal period, is preserved with HRT, and is improved with PTH treatment in postmenopausal women.

Animals↗
PubMed1999

The role of chondrocytes in intramembranous and endochondral ossification during distraction osteogenesis in the rabbit.

We have used a rabbit leg-lengthening model for detailed studies of the histology of distraction osteogenesis. Some unusual features of the endochondral ossification that occurs during the rapid transition of cartilage to bone in the regenerate were observed. Histological staining techniques together with immunohistochemistry and nonradioactive in situ mRNA hybridization for cartilage and bone-related molecules have been used to document the presence of an overlapping cartilage-bone phenotype in cells of the cartilage-bone transitional region. In those particular areas, some chondrocytes appeared to be directly transformed into newly formed bone trabeculae which are surrounded by bone matrix. Acid phosphatases were found within the cartilage matrix in some of the cartilage/bone transitional regions and type I collagen mRNA and type II collagen protein were found together in some of the marginal hypertrophic chondrocytes. This study indicates an unusual role of chondrocytes in the process of ossification at a distraction rate of 1.3 mm/day in the rabbit. Further direct evidence is required to prove the hypothesis that the hypertrophic chondrocytes may transdifferentiate into bone cells in this model.

Acid Phosphatase↗
PubMed1986

Late positional correction of uniting femoral fractures using the Wagner external fixator.

The use of the Wagner leg lengthening external fixator is described in six patients with extensive segmental fractures of the femoral shaft. Good fixation of the fracture is combined with the facility for distraction and lengthening of the early reparative callus up to 10 weeks after injury. The method is recommended for those patients in whom shortening and malalignment of the fracture persist as union proceeds.

Adult↗
PubMed1987

Changes in post-tetanic potentiation of neuromuscular transmission in chronically stretched muscle.

1. Changes in the parameters of the magnitude of PTP of m.e.p.p. frequency were examined in rat soleus muscles chronically stretched for a variety of durations (4-28 days) by leg-lengthening operations. 2. On day 4 after the operation, the magnitude of PTP in the stretched muscles obviously increased compared to the control muscles. This indicates that Ca2+-conductance in the nerve terminals increases in the stretched muscles at day 4. 3. On day 7 after the operation, there was no significant difference between the magnitudes of PTP in the control and stretched muscles. 4. After day 14 following the operation, the magnitude of PTP in the stretched muscles was smaller than that in the control muscles. This indicates that Ca2+-conductance in the nerve terminals decreases in the stretched muscles after day 14.

Action Potentials↗
PubMed1994

Peripheral neuropathies following total hip arthroplasty.

The authors reviewed the complication records following total hip arthroplasty at their institution between January 1976 and July 1989. Forty-two patients (12 men and 30 women) with 45 neurologic complications were identified following 7,133 consecutive total hip arthroplasties; an incidence rate of 0.63%. The average age of these patients was 58 years (range, 27-81 years). Thirty-four nerve injuries were noted in the lower extremity (0.48% incidence rate) and 11 in the upper extremity (0.15% incidence rate). The majority of patients (64%) with neurologic injury to the upper extremity had the diagnosis of inflammatory arthritis. The common peroneal was most often involved in the lower extremity. The ulnar nerve was most commonly involved in the upper extremity. The pathogenetic factors leading to neurologic injury in the majority of patients were not clearly established. Leg lengthening did not seem to be a major cause. The prognosis of patients with nerve palsy of the upper extremity is favorable compared with injury to the lower extremity. Similarly, the percentage of patients with a permanent neurologic deficit was lower in the primary surgery group (27%) compared with the revision/reoperation group (43%). The overall percentage of permanent nerve palsy was 33%. Female patients, for unclear reasons, appear to have a higher risk for neurologic injury. Also, the risk of neurologic injury following total hip arthroplasty appears to be higher with revisions/reoperations and with an inexperienced surgeon.

Adult↗
PubMed2004

Efforts to improve cementless femoral stems in THR: 2- to 5-year follow-up of a high-offset femoral stem with distal stem modification (Secur-Fit Plus).

A retrospective review of 81 sequential primary total hip arthroplasties using a cementless, high-offset femoral stem was performed. Follow-up was 24 to 60 months. The average age at the time of surgery was 54 years. The femoral bone types were: 36% Dorr A, 51% Dorr B, and 13% Dorr C. The mean postoperative Harris Hip Score was 95. The mean postoperative Oxford score was 17. Eighty-five percent had no clinical leg-length difference. All stems were radiographically stable. The stem features of hydroxyapatite coating on a rough circumferential titanium arc-deposit proximal surface in conjunction with distal flutes seem to provide immediate stability, making this implant clinically versatile. Potential benefits of increased offset include improved joint stability and avoidance of leg lengthening.

Arthroplasty, Replacement, Hip↗
PubMed2006

The role of ring external fixation in Charcot foot arthropathy.

These two morbidly obese patients with severe Charcot foot arthropathy were treated successfully with percutaneous correction of their deformity followed by a stepwise application of a pre-assembled neutrally aligned multiplane ring external fixator. This technique transfers well to the trauma environment in which alignment can be maintained without further violation within the zone of injury. The application of the fine wire ring external fixation has been used for many years to accomplished leg lengthening and correction of deformity. Historically it has required a great deal of experience to apply to complex frames and implement the required daily adjustments. The patient experience often has been an unpleasant ordeal with a high potential for associated morbidity. This negative exposure has prompted practicing orthopedic surgeons to avoid this technique, feeling that it best be left to those in tertiary care setting who are equipped to handle the morbidity and complications. Taking this technology from the domain of the deformity surgeon to the general orthopedic community will require the suppression of bad memories from residency. Using the device solely as a method of maintaining alignment eliminates many of the dynamic attributes that contributes to pain and morbidity. The bone and soft tissues are not stretched, eliminating much of the pain and decreasing the rate of traction-associated pin tract morbidity. Because there is no dynamic of the treatment, the simplified frame can be pre-assembled and have no adjustable components. The experience derived from this application has the potential of expanding the role of ring external fixation. Where the ring has been used previously as method of both obtaining and maintaining alignment, this application uses a simplified neutral version of a complex device to simply maintain alignment in a high risk patient population. Correction of deformity and achieving alignment/reduction of fractures is well within the domain of practicing orthopedic surgeon. Once that correction has been achieved, this application simply maintains that correction. It helps avoid extensive surgical dissection in a poor host and eliminates the need for bone that is mechanically capable of holding internal fixation devices during the bony and soft tissue healing period.

Adult↗
PubMed2004

Intermittent parathyroid hormone (1-34) enhances mechanical strength and density of new bone after distraction osteogenesis in rats.

Distraction osteogenesis is used both for leg lengthening and for bone transportation in the treatment of fractures and nonunions. The main problem with this method is that the time until full recovery may be up to a year, partly because of the time needed for the new formed bone to consolidate and become strong enough for weight bearing. We have studied whether intermittent parathyroid hormone (PTH(1-34)) could accelerate the consolidation of new formed bone after distraction osteogenesis in rats. Forty-seven, 3-months-old male Sprague-Dawley rats underwent lengthening of the right femur using an external fixator. After a middiaphyseal osteotomy and a 7-day latency period, the callus was distracted during 10 days, with a distraction rate of 0.25 mm twice a day. The consolidation time was either 20 days or 40 days after distraction was completed. A dose of 60 microg of human PTH(1-34)/kg body weight/injection or vehicle was given every second day beginning 30 days before the rats were killed. Both femura of each rat were subjected to mechanical testing and dual-energy X-ray absorptiometry. Blinded histological examination was done for the distracted femura. In the 20 days consolidation experiment, PTH(1-34) increased ultimate load (56%), stiffness (117%), total regenerate callus volume (58%), callus BMC (24%) and histologic bone density (35%) compared to untreated distraction osteogenesis specimens. In the 40 days consolidation experiment, PTH(1-34) increased ultimate load (54%), stiffness (55%), callus BMC (33%) and histologic bone density (23%) compared to untreated distraction osteogenesis specimens. Total regenerate callus volume was unchanged. The contralateral femur also became stronger, stiffer and denser under PTH(1-34) treatment, but to a lesser degree. PTH(1-34) might become useful to shorten the consolidation time after distraction osteogenesis in humans.

Animals↗
PubMed2005

Bone formation is enhanced by thrombin-related peptide TP508 during distraction osteogenesis.

The thrombin-related peptide, TP508, has been shown to promote soft tissue healing and fracture repair. One possible clinical application of TP508 is to accelerate bone regeneration during distraction osteogenesis, which is a lengthy procedure involving significant complications. In this study, we tested the ability of TP508 to accelerate the consolidation phase of distraction osteogenesis in a rabbit model of leg lengthening. Twenty-three rabbits had left tibiae lengthened for 1 cm over a period of 6 days. TP 508 (0, 30 and 300 microg in 300 microl saline) was injected into the distraction gaps at the beginning and the end of the lengthening phase, and all the animals were killed 2 weeks after lengthening. By the end of experiment, more animals in the TP508 treated groups had complete bony union of the distraction gaps when compared to the saline treated group. pQCT examination of the regenerates demonstrated a significantly greater bone mineral density (BMD) in the TP508 treated groups relative to the saline control group, but no statistical difference in the BMD was found between the two dosages of TP508. Bone consolidation and bone remodeling was far advanced in the TP508 300 microg treated group, and the regenerates mainly consisted of well-vascularized woven bone. In contrast, in the group that received the 30 microg TP508 treatment, focal bone defects and discontinuities of the new cortices were evident in some but not all animals. In the saline control group a majority of the animals showed large amounts of fibrous and cartilaginous tissues in the regenerates, and none of the regenerates had completed consolidation. This study has demonstrated that local application of TP508 enhanced bone formation and consolidation during distraction osteogenesis in the rabbit. The findings indicate that TP508 may be useful in promoting osteogenesis in situations when augmentative treatment for bone formation and consolidation are needed.

Animals↗
PubMed2002

Bone consolidation is enhanced by rhBMP-2 in a rabbit model of distraction osteogenesis.

Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a differentiation factor which has been shown to induce bone formation and heal bony defects in a variety of animal models. A possible application of rhBMP-2 is to accelerate bone regeneration during distraction osteogenesis. which clinically is a long procedure, often involving significant complications. In this study we tested the ability of rhBMP-2 to accelerate the consolidation phase of distraction osteogenesis in a rabbit model of leg lengthening. Tibiae were lengthened 2 cm over a period of ten days. rhBMP-2 was administered at the end of the lengthening phase. Two modes of rhBMP-2 application were tested: surgical implantation of rhBMP-2/ACS (absorbable collagen sponge) into the regenerate (50 microl of 1.5 mg/ml rhBMP-2, total dose = 75 microg rhBMP-2), and percutaneous injection of rhBMP-2/buffer (0.1 ml of 0.75 mg/ml rhBMP-2. total dose = 75 microg rhBMP-2) into three sites within the regenerate. Also, there were three groups of control animals: (1) no surgical intervention, (2) surgical implantation of buffer/ACS and (3) percutaneous injection of buffer. Rabbits were sacrificed at 5, 14 and 28 days after the interventions. Radiographic evaluation indicated a significant increase in bony union of the distraction regenerate in the rhBMP-2 treated groups compared with the untreated groups at 5 and 14 days. At 28 days, formation of a cortex and reestablishment of the medullary canal was evident only in the rhBMP-2 treated groups. The bone mineral content (BMC) of the regenerate was significantly higher in the rhBMP-2 treated groups at 5 and 14 days. However, at 28 days, BMC of the regenerate was similar in all groups. The average volumetric density of the regenerate was significantly higher in the rhBMP-2 injection group at day 14. In Summary, both injection of rhBMP-2/buffer and implantation of rhBMP-2/ACS enhanced the consolidation stage of distraction osteogenesis in this rabbit model.

Animals↗