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PubMed2000

Congenital transverse deficiency of the tibia and fibula: a report of two cases.

We report two similar, but unrelated, patients with congenital bilateral partial deficiencies of the tibia and fibula associated with intact feet. In both patients, the tibia and fibula were absent on initial radiographs, while the femur and the tarsal bones were well developed and there was bilateral teratologic dislocation of the hips. Ultrasound and magnetic resonance imaging (MRI) studies suggested the presence of cartilaginous remnants of the tibia and fibula. There were multidirectional instabilities in the knees and ankles. The clinical and radiological features of these cases are distinct from those of congenital longitudinal deficiency of the tibia, in which the fibula is always preserved, and from longitudinal deficiency of the fibula, in which the tibia is present and the foot is usually involved. We suggest that the bilateral partial deficiencies of the tibia and fibula associated with the intact foot and teratologic dislocation of the hips is a single-entity disorder, possibly categorized as an intercalary transverse deficiency of the lower limb.

Abnormalities, Multiple↗
PubMed2001

Effects of running exercise on the mandible and tibia of ovariectomized rats.

To examine the effects of running exercise on the mandible and tibia of ovariectomized (OVX) rats, 26-week-old sham-operated (Sham) and OVX rats 1 week post-ovariectomy were subjected to non-exercise (Sham-Cont and OVX-Cont) and exercise (Sham-Exc and OVX-Exc) for 8 weeks. OVX induced a significant decrease in alkaline phosphatase (ALP) and an increase in tartrate-resistant acid phosphatase (TRAP) activity and a reduction of 17beta-estradiol in the serum. In OVX-Cont rats, histology and bone mineral density (BMD) showed bone loss in the proximal tibia, and histology, soft X-ray photographs and bone marrow area (BMA) revealed enlargement of the bone marrow cavity in the neck of the condylar process. In OVX-Exc rats, exercise significantly increased ALP activity, decreased TRAP activity and markedly elevated serum progesterone levels. Histology and BMD in the tibia and histology, X-ray photographs and BMA in the mandible were comparable to those in Sham rats. In Sham-Exc rats, unexpected decreases were observed in serum enzymes and hormones, but the histology and BMD in the tibia and histology, X-ray photographs and BMA in the mandible were very similar to those in Sham-Cont rats, suggesting a decrease of bone turnover with no change of bone mass in the tibia and mandible. We conclude that exercise has a beneficial effect not only on bone loss in the tibia, but also on differential changes in the neck of the condylar process, perhaps by increasing serum levels of progesterone in OVX rats.

Alkaline Phosphatase↗
PubMed1983

Mechanical properties of the tibia from chickens with idiopathic scoliosis.

The tibia from six-week old chickens that develop idiopathic scoliosis were studied with stress relaxation experiments and torsional strength testing. Most parameters observed did not show any significant differences between tibias obtained from chickens with scoliosis and tibias from the control birds; however, the rate of stress relaxation of the tibia from the birds with scoliosis was minimally increased over the controls. There were no significant differences noted in ultimate torsional strength, maximum angular deformity or modulae of torsional rigidity of the tibias from scoliotic chickens when compared to tibias from control chickens.

Animals↗
PubMed2002

Chronic anterior cruciate ligament deficiency is associated with increased anterior translation of the tibia during the transition from non-weightbearing to weightbearing.

Translation of the tibia relative to the femur was measured while a group of subjects with normal knees and group with anterior cruciate ligament (ACL) tears underwent transition from non-weightbearing to weightbearing stance. Subjects were positioned in the Vermont knee laxity device (VKLD) with muscles relaxed and the limb segment and compressive joint load offset (non-weightbearing). A lateral radiograph of the knee, with the posterior aspects of the femoral condyles superimposed, was obtained to document the position of the tibia relative to the femur. Immediately after, a compressive load equal to 40% of bodyweight was applied to each foot, and a second radiograph was obtained to document the change in position of the tibia relative to the femur. The transition from non-weightbearing to weightbearing produced a significant increase of anterior translation of the tibia relative to the femur (mean; 3.4 mm) for the subjects with ACL tears compared with the contralateral normal knees (0.8 mm). Similarly, there was a significant increase in anterior translation of the tibia for the subjects with ACL tears compared to the group of subjects with normal knees (1.2 mm). The fourfold increase in anterior translation of the tibia for the knees with ACL tears compared to the contralateral side is a concern because it is substantially greater than the 95% confidence limits of the side-to-side differences in anterior-posterior knee laxity measured from subjects with normal knees. This observation could explain, at least in part, one of the mechanisms that initiates damage to the meniscus and articular cartilage in subjects that have suffered an ACL tear.

Adult↗
PubMed1997

An experimental in vivo method for analysis of local deformation on tibia, with simultaneous measures of ground reaction forces, lower extremity muscle activity and joint motion.

This paper presents the pilot procedures of a new in vivo experimental method for measures of local bone deformation on tibia. The tibia transducer consists of a strain gauge mounted on a surgical staple, and was designed to measure local bone deformation. Pilot measurements were undertaken during two standardized conditions of forefoot and heel landing in seven healthy volunteers. Implantation of two tibia force transducers on tibia were performed under local anaesthesia. The local peak tibia deformation occurred at 20-42 ms (median) after ground contact, and was up to eight times higher during stance phase loading compared with standing still on one leg. Ground reaction forces, muscle activation patterns and kinematics were registered simultaneously, and were used to validate that the observed local deformation on tibia occurred under controlled and clinically relevant conditions. The new method may be used for investigating local deformation within various bone structures of the lower extremity. There are further methodological issues to address before major clinical interpretations may be concluded. In order to verify that the strain gauge transducer system was valid, a controlled displacement of the staple shanks was performed with a micrometer, and showed a linear relationship between applied deformation and strain gauge response (r = 0.97-0.99). In addition, a linear relationship was found between externally applied static forces and strain gauge response in a four-point bending cadaver system (r = 0.96-0.98).

Adult↗
PubMed1998

The fibular incisure of the tibia on CT scan: a cadaver study.

Twenty cadaver lower limbs were used for CT assessment of the fibular incisure of the tibia. The length of the syndesmotic facet is shorter in the anterior (11.20 +/- 1.90 mm) than in the posterior (14.89 +/- 2.72 mm) (P < 0.001). The angle between anterior and posterior facets is 135.18 +/- 9.27 degrees. The depth of the fibular incisure of the tibia is 4.29 +/- 1.26 mm. The vertical distance of tibiofibular overlapping is 7.81 +/- 1.93 mm. The distance between anterior margin of the tibia and anterior margin of the fibula is 17.40 +/- 3.61 mm. The distance between the medial fibular border and the lateral border of the posterior tibia is 2.01 +/- 0.49 mm. The syndesmotic notch could be divided into two groups: significant concave surface and shallow concave surface. The position of the fibula in the incisural notch may depend on the depth of the fibular incisure of the tibia during traumatic forces applied on the syndesmosis. CT can display the tibial tubercles and clearly demonstrates the fibular incisure of the tibia and the interior of the tibiofibular space.

Aged↗
PubMed2000

Associations of blood lead, dimercaptosuccinic acid-chelatable lead, and tibia lead with polymorphisms in the vitamin D receptor and [delta]-aminolevulinic acid dehydratase genes.

A cross-sectional study was performed to evaluate the influence of polymorphisms in the [delta]-aminolevulinic acid dehydratase (ALAD) and vitamin D receptor (VDR) genes on blood lead, tibia lead, and dimercaptosuccinic acid (DMSA)-chelatable lead levels in 798 lead workers and 135 controls without occupational lead exposure in the Republic of Korea. Tibia lead was assessed with a 30-min measurement by (109)Cd-induced K-shell X-ray fluorescence, and DMSA-chelatable lead was estimated as 4-hr urinary lead excretion after oral administration of 10 mg/kg DMSA. The primary goals of the analysis were to examine blood lead, tibia lead, and DMSA-chelatable lead levels by ALAD and VDR genotypes, controlling for covariates; and to evaluate whether ALAD and VDR genotype modified relations among the different lead biomarkers. There was a wide range of blood lead (4-86 microg/dL), tibia lead (-7-338 microg Pb/g bone mineral), and DMSA-chelatable lead (4.8-2,103 microg) levels among lead workers. Among lead workers, 9.9% (n = 79) were heterozygous for the ALAD(2) allele and there were no homozygotes. For VDR, 10.7% (n = 85) had the Bb genotype, and 0.5% (n = 4) had the BB genotype. Although the ALAD and VDR genes are located on different chromosomes, lead workers homozygous for the ALAD(1) allele were much less likely to have the VDR bb genotype (crude odds ratio = 0.29, 95% exact confidence interval = 0.06-0.91). In adjusted analyses, subjects with the ALAD(2) allele had higher blood lead levels (on average, 2.9 microg/dL, p = 0.07) but no difference in tibia lead levels compared with subjects without the allele. In adjusted analyses, lead workers with the VDR B allele had significantly (p < 0.05) higher blood lead levels (on average, 4.2 microg/dL), chelatable lead levels (on average, 37.3 microg), and tibia lead levels (on average, 6.4 microg/g) than did workers with the VDR bb genotype. The current data confirm past observations that the ALAD gene modifies the toxicokinetics of lead and also provides new evidence that the VDR gene does so as well.

Adolescent↗
PubMed2005

Relationship between bone morphology and bone quality in male tibias: implications for stress fracture risk.

UNLABELLED: Biomechanical properties were assessed from the tibias of 17 adult males 17-46 years of age. Tissue-level mechanical properties varied with bone size. Narrower tibias were comprised of tissue that was more brittle and more prone to accumulating damage compared with tissue from wider tibias. INTRODUCTION: A better understanding of the factors contributing to stress fractures is needed to identify new prevention strategies that will reduce fracture incidence. Having a narrow (i.e., more slender) tibia relative to body mass has been shown to be a major predictor of stress fracture risk and fragility in male military recruits and male athletes. The intriguing possibility that slender bones, like those shown in animal models, may be composed of more damageable material has not been considered in the human skeleton. MATERIALS AND METHODS: Polar moment of inertia, section modulus, and antero-posterior (AP) and medial-lateral (ML) widths were determined for tibial diaphyses from 17 male donors 17-46 years of age. A slenderness index was defined as the inverse ratio of the section modulus to tibia length and body weight. Eight prismatic cortical bone samples were generated from each tibia, and tissue-level mechanical properties including modulus, strength, total energy, postyield strain, and tissue damageability were measured by four-point bending from monotonic (n = 4/tibia) and damage accumulation (n = 4/tibia) test methods. Partial correlation coefficients were determined between each geometrical parameter and each tissue-level mechanical property while taking age into consideration. RESULTS: Significant correlations were observed between tibial morphology and the mechanical properties that characterized tissue brittleness and damageability. Positive correlations were observed between measures of bone size (AP width) and measures of tissue ductility (postyield strain, total energy), and negative correlations were observed between bone size (moment of inertia, section modulus) and tissue modulus. CONCLUSIONS: The correlation analysis suggested that bone morphology could be used as a predictor of tissue fragility and stress fracture risk. The average mechanical properties of cortical tissue varied as a function of the overall size of the bone. Therefore, under extreme loading conditions (e.g., military training), variation in bone quality parameters related to damageability may be a contributing factor to the increased risk of stress fracture for individuals with more slender bones.

Adolescent↗
PubMed2007

Effect of mechanical loading on insulin-like growth factor-I gene expression in rat tibia.

Mechanical loading plays an essential role in maintaining skeletal integrity. Mechanical stimulation leads to increased bone formation. However, the cellular and molecular mechanisms that are involved in the translation of mechanical stimuli into bone formation, are not completely understood. Growth factors and osteocytes, which act as mechanosensors, play a key role during the bone formation after mechanical stimulation. The aim of this study was to characterize the role of IGF-I in the translation of mechanical stimuli into bone formation locally in rat tibiae. Fifteen female Wistar rats were randomly assigned to three groups (n = 5): load, sham-loaded, and control. The four-point bending model of Forwood and Turner was used to induce a single period of mechanical loading on the tibia shaft. The effects of mechanical loading on IGF-I mRNA expression were determined with non-radioactive in situ hybridization on decalcified tibiae sections, 6 h after the loading session. Endogenous IGF-I mRNA was expressed in trabecular and cortical osteoblasts, some trabecular and sub-endocortical osteocytes, intracortical endothelial cells of blood vessels, and periosteum. Megakaryocytes, macrophages, and myeloid cells also expressed IGF-I mRNA. In the growth plate, IGF-I mRNA was located in proliferative and hypertrophic chondrocytes. Mechanical loading did not affect the IGF-I mRNA expression in osteoblasts, bone marrow cells, and chondrocytes, but the osteocytes at the endosteal side of the shaft showed a twofold increase of IGF-I mRNA expression. The proportion of IGF-I mRNA positive osteocytes in loaded tibiae was 29.3 +/- 12.9% (mean +/- s.d.; n = 5), whereas sham-loaded and contra-lateral control tibiae exhibited 16.7 +/- 4.4% (n = 5) and 14.7 +/- 4.2% (n = 10) respectively (P < 0.05). Lamellar bone formation after a single mechanical loading session was observed at the endosteal side of the shaft. In conclusion, a single loading session results in a twofold up-regulation of IGF-I mRNA synthesis in osteocytes which are present in multiple layers extending into the cortical bone of mechanically stimulated tibia shaft 6 h after loading. This supports the hypothesis that IGF-I, which is located in osteocytes, is involved in the translation of mechanical stimuli into bone formation.

Animals↗
PubMed2000

Osteochondromas of the distal aspect of the tibia or fibula. Natural history and treatment.

BACKGROUND: There is little information on the natural history or treatment of osteochondromas arising from the distal aspect of either the tibia or the fibula. It is believed that there is a risk of deformation of the ankle if these exostoses are left untreated or if the physis or neurovascular structures are injured during operative intervention. METHODS: We reviewed the records of twenty-three patients who had been treated for osteochondroma of the distal aspect of the tibia or fibula between 1980 and 1996. Four of the patients had hereditary multiple cartilaginous exostoses. There were seventeen male and six female patients, and the average age at the time of presentation was sixteen years (range, eight to forty-eight years). RESULTS: Preoperative radiographs showed evidence of plastic deformation of the fibula in eleven patients who had a large osteochondroma. Four patients elected not to have an operation. The tumor was excised in nineteen patients. Postoperatively, all nineteen patients had a Musculoskeletal Tumor Society score of 100 percent for function of the lower extremity with pain-free symmetrical and unrestricted motion of the ankle at the latest follow-up examination. Partial remodeling of the tibia and fibula gradually diminished the asymmetry of the ankles in all nineteen operatively managed patients; however, the remodeling was most complete in the younger patients. Pronation deformities of the ankle did not change after excision of the tumor. Complications of operative treatment included four recurrences (only three of which were symptomatic), one sural neuroma, one superficial wound infection, and one instance of growth arrest of the distal aspects of the tibia and fibula. CONCLUSIONS: Osteochondromas of the distal and lateral aspects of the tibia were more often symptomatic than those of the distal aspect of the fibula; they most commonly occurred in the second decade of life with ankle pain, a palpable mass, and unrestricted ankle motion. Untreated or partially excised lesions in skeletally immature patients may become larger and cause plastic deformation of the tibia and fibula and a pronation deformity of the ankle. Ideally, operative intervention should be delayed until skeletal maturity, but, in symptomatic patients, partial excision preserving the physis may be necessary for the relief of symptoms and the prevention of progressive ankle deformity. However, partial excision is associated with a high rate of recurrence, so a close follow-up is required. Skeletally mature patients who are symptomatic may require excision of the tumor.

Adolescent↗
PubMed2003

The effect of alendronate on bone mineral density in the distal part of the femur and proximal part of the tibia after total knee arthroplasty.

BACKGROUND: Bone mineral density around the knee is related to the mechanical properties of bone. Alendronate has been shown to be effective for the treatment of osteoporosis and for reducing the rate of osteoporotic fractures. The purpose of the present study was to investigate the effect of alendronate on bone mineral density in the distal part of the femur and proximal part of the tibia after total knee arthroplasty in women. METHODS: Ninety-six women with an average age of seventy years who were undergoing total knee arthroplasty were randomly divided into two groups. Patients in the study group received oral alendronate at a dose of 10 mg/day for six months, whereas patients in the control group did not. The bone mineral density in the distal part of the femur and proximal part of the tibia was determined preoperatively and at six and twelve months postoperatively. RESULTS: In the control group, the bone mineral density showed significant decreases of 13.8% (p < 0.001) and 7.8% (p = 0.003) in the distal part of the femur and of 6.5% (p = 0.002) and 3.6% (p = 0.141) in the proximal part of the tibia at six and twelve months, respectively. In the study group, however, the bone mineral density showed significant increases of 10.0% (p = 0.010) and 1.9% (p = 0.049) in the distal part of the femur and of 9.4% (p < 0.001) and 5.4% (p = 0.032) in the proximal part of the tibia at six and twelve months, respectively. The overall differences in bone mineral density between the study and control groups were significant (p = 0.011 for the proximal part of the tibia, and p = 0.033 for the distal part of the femur). CONCLUSIONS: We found significant postoperative decreases in bone mineral density in the distal part of the femur and proximal part of the tibia in women who had undergone total knee arthroplasty. Oral administration of alendronate for six months postoperatively significantly improved the bone mineral density. While the clinical benefits of alendronate after total knee arthroplasty remain unproven and the duration of follow-up in the present study was quite short, the improvement in bone mineral density may have a clinically important effect on prosthetic fixation and the rate of periprosthetic fractures after total knee arthroplasty.

Absorptiometry, Photon↗
PubMed2005

Outcome of hemiepiphyseal stapling for late-onset tibia vara.

BACKGROUND: The results of hemiepiphysiodesis for the treatment of late-onset tibia vara have been reported to be favorable, but the technique requires careful timing and an accurate estimation of skeletal age. Hemiepiphyseal stapling does not require a careful estimation of skeletal age, and it has been reported to yield good results with low morbidity. However, we are not aware of any study evaluating the intermediate-term radiographic results or complications of this procedure. METHODS: Twenty-six patients with thirty-three extremities with late-onset tibia vara were treated with proximal tibial hemiepiphyseal stapling. Fourteen extremities had substantial concomitant distal femoral varus and also had hemiepiphyseal stapling of the distal part of the femur. Eighteen patients (twenty-three involved extremities) had juvenileonset tibia vara and eight patients (ten involved extremities) had adolescent-onset tibia vara. The mean age at the time of stapling was 11.8 years. The mean duration of follow-up was 3.8 years. We reviewed standardized standing radiographs to determine the mechanical axis deviation, the medial proximal tibial angle, the lateral distal femoral angle, and the zone of the knee through which the mechanical axis passed. RESULTS: The mean mechanical axis deviation improved from 58 mm (range, 27 to 157 mm) preoperatively to 22 mm (range, -33 to 117 mm) at the time of the last follow-up, and the mean medial proximal tibial angle improved from 77 degrees (range, 50 degrees to 85 degrees ) to 85 degrees (range, 48 degrees to 95 degrees ). In the fourteen lower extremities in which distal femoral hemiepiphyseal stapling was performed, the mean lateral distal femoral angle improved from 96 degrees (range, 92 degrees to 100 degrees ) to 86 degrees (range, 79 degrees to 97 degrees ). At the time of the final follow-up, seven extremities were considered to be in moderate varus; four, in mild varus; twenty, in normal alignment; and two, in valgus. No differences in radiographic outcome were noted between the juvenile and adolescent forms of tibia vara. Only one of the four extremities with severe preoperative varus was corrected to normal alignment; the remaining three were left with moderate varus. CONCLUSIONS: Hemiepiphyseal stapling of the lateral aspect of the proximal tibial physis and, as needed, the lateral aspect of the distal femoral physis is safe and effective in children with late-onset tibia vara if the physes are sufficiently open and the varus deformity is mild to moderate. Hemiepiphyseal stapling is particularly effective in patients who are ten years of age or younger. LEVEL OF EVIDENCE: Therapeutic Level IV.

Adolescent↗
PubMed1990

Stress protection by external fixation of the rabbit tibia.

Osteopenia of the tibia and femur caused by an external fixator in the tibia was studied in 14 rabbits. Eight rabbits were treated with a complete unilateral external fixator in one tibia, whereas the other tibia served as control. The other 6 animals had one leg operated on with inserting of all the pins but without the frame. This technique was chosen to compare osteopenia caused by stress protection and the effect of the pins. After 6 weeks, we found a 7 percent reduction in the bone mineral content in the tibial diaphyseal segment between the pins of the external fixator and no bone loss in the tibia that were operated on with only pins. In the femurs, there was a smaller decrease in the bone mineral content: respectively 3.2 percent (complete frame) and 2.9 percent (only pins). On all the operated on tibiae, there was an increase in the bone mineral content around the pins both proximally and distally.

Animals↗
PubMed1989

Effect of dietary sodium zeolite A and excess calcium on growth and tibia calcium and phosphorus concentration in uninfected and Eimeria acervulina-infected chicks.

Two identical trials were conducted with 5 to 14-day-old broiler chicks. Sodium zeolite A (NZA, 0 and .75%) and Ca (1.0 and 1.5%) were fed to both uninfected and Eimeria acervulina-infected chicks resulting in a 2 x 2 x 2 factorial arrangement of treatments. Coccidial infection reduced weight gain and gain:feed (P less than .01), and tibia ash, Ca, and Ca:P ratio (P less than .05). Excess dietary Ca reduced (P less than .05) weight gain and tibia ash in uninfected chicks but had no effect (P greater than .10) in coccidiosis-infected chicks (Ca x coccidiosis interaction, P less than .05). Addition of NZA to diets with excess Ca further decreased (P less than .05) weight gain and tibia ash in both uninfected and E. acervulina-infected chicks. Tibia Ca, as a percentage of dry fat-free tibia, was reduced (P less than .05) by the addition of NZA. This effect was not observed when tibia Ca was expressed as a percentage of ash. These results suggest that NZA may exacerbate the adverse effects of excess dietary Ca.

Aluminum Silicates↗
PubMed1990

Influence of vitamin D3, 1 alpha-hydroxyvitamin D3, and 1,25-dihydroxyvitamin D3 on eggshell quality, tibia strength, and various production parameters in commercial laying hens.

Four hundred 53-wk-old Hyline W36 laying hens were randomly allocated to 10 treatments. The effects of feeding two vitamin D3 metabolites, 1 alpha-hydroxyvitamin D3 [1 alpha-(OH) D3] and 1,25-dihydroxyvitamin D3 [1,25-(OH)2 D3], each at five dietary levels (0, .75, 1.50, 3.00, and 4.50 micrograms/kg of feed) were determined on eggshell quality and tibia strength in commercial laying hens (Experiment 1). In Experiment 2, 1,440 Hyline W36 65-wk-old laying hens were used to determine the effects of four levels of vitamin D3 (0, 500, 1,000, and 1,500 ICU vitamin D3/kg) and three levels of dietary 1,25-(OH)2 D3 (0, .5, and 1.0 microgram/kg of feed) on eggshell quality, tibia strength, and egg production. In Experiment 1, neither 1,25-(OH)2 D3 nor 1 alpha-(OH) D3 affected eggshell quality or production criteria. Tibia weight was increased by adding either 1,25-(OH)2 D3 or 1 alpha-(OH) D3. In Experiment 2, 1,25-(OH)2 D3 increased percentage of shell, shell weight, and egg breaking strength when 0 ICU D3/kg was fed but had no effect at higher levels of vitamin D3. Egg production, feed consumption, and egg weight were also increased with supplemental 1,25-(OH)2 D3 when 0 ICU D3/kg was fed. Tibia weight and tibia breaking strength were also increased by adding 1,25-(OH)2 D3 to the diet. The commercial laying hen metabolizes sufficient 1,25-(OH)2 D3 from dietary vitamin D3 to maintain shell quality but not enough to maintain tibia strength.

Animals↗
PubMed1989

Adolescent tibia vara.

Adolescent tibia vara is less common and less well described when compared to infantile tibia vara. Yet, the two share a significant number of features related to their epidemiology and histology. The two diseases differ most in their radiographic appearance. It does not, however, necessarily follow that their etiologies cannot be similar. By its epidemiology and histology, adolescent tibia vara appears to be related to repetitive trauma in the form of abnormal force directed on the medial tibial growth plate due to obesity, the adolescent growth spurt, or residual, incompletely corrected physiologic varus. Such forces may give growth plate suppression by the Heuter Volkman principle similar to what is thought to occur in infantile tibia vara. In the infant, this results in typical radiologic findings related to an epiphyseal ossification center which is cartilagenous and moldable and results in progressive medial wedging. In the adolescent, however, this ossification center is bony and, therefore, will not deform under stress. The growth plate, however, still responds with decreased growth resulting in varus deformity. Thus, adolescent tibia vara, by definition not related to trauma or infection, may in fact reflect the same pathologic process at work as in infantile tibia vara.

Child↗
PubMed2001

[The therapy effect of improved bilateral tibia lengthening].

OBJECTIVE: To study the therapy effect of improved bilateral tibia lengthening. METHODS: From May 1997 to May 2000, 32 patients (varus knee deformity in 8 cases) with low stature were adopted in this study. Among them, there were 26 females and 6 males, aged from 18 to 45 years old. Operative procedures included: 1. tibia osteotomy 1 cm distal from tibia tuberosity and fibula osteotomy 10 cm proximal from lateral malleolus; 2. fixation of the tibia osteotomy with interlocking nail and locking the proximal nail; 3. fixation of the lengthening apparatus; 4. lengthened bilateral tibia 0.7 mm per day; 5. removed the apparatus and locked the distal nail 2 weeks later after limb lengthening was over. RESULTS: The mean distance of lengthening was 8.5 cm (ranged 3.5 to 12.0 cm), the mean duration of lengthening was 128 days(ranged 53 to 180 days), and the mean time of bone union was 180 days (ranged 120 to 270 days). Followed up for 1 to 3 years, 98% patients felt satisfactory in lengthening, gait and joint movement. CONCLUSION: The improved bilateral tibia lengthening technique is recommended for advantage of short time of bone union, less complication and correcting the varus deformity of knee simultaneously.

Adolescent↗
PubMed2006

[Limb salvage with osteoarticular allografts after resection of proximal tibia bone].

OBJECTIVE: To evaluate the short-term efficacy of osteoarticular allografts in the limb salvage of the proximal tibia. METHODS: From 1998 to 2003, 15 patients (7 males, 8 females; aged 14-56 yr. average 33) with bone tumor of the proximal tibia underwent osteoarticular allografts. among whom 7 had progressive giant cell tumor without any previous chemotherapy; 8 had malignant tumor with previous chemotherapy, including 6 patients with osteosarcoma, 1 with spindle cell sarcoma, and 1 with malignant fibrous histiocytoma. According to the Enneking system, the patients were classified into I B (7 patients), II A (2 patients), and II B (6 patients). All the patients underwent the marginal resection with an allograft (average length 12 cm, range 6-16 cm) implanted. RESULTS: The follow-up for an average of 21 months (range, 3-58 months) revealed that among the 8 patients with malignant tumor of the proximal tibia undergoing chemotherapy, 5 had union of the bone, 3 had no union of the bone; among the 3 patients, 2 had a complication of infection and 1 had a local recurrence. All the 3 patients underwent amputation at the lower part of the femur. According to the Mankin score, 2 patients had a perfect result, 2 good, 1 fair, and 3 poor, with a 50% effectiveness rate. Among the 7 patients with progressive giant cell tumor at the upper part of the tibia, none had infection or local recurrence, but 2 had nonunion of the bone and 2 had joint instability, aided by the knee-aiding system. According to the Mankin score, 3 patients had a perfect result, 2 good, and 2 fair, with a 71% effectiveness rate. CONCLUSION: The osteoarticular allograft of the proximal tibia has many advantages in spite of a relatively high rate of complications, and it is the limb salvage of choice for the progressive benign or malignant bone tumors of the proximal tibia.

Adolescent↗