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A method for perfusion of isolated canine tibia is described. With this procedure the influence of different albumins on the uptake of tritiated 25-hydroxyvitamin D3 (3H-25(OH)D3) by the tibia has been studied. Bovine serum albumin at 1% concentration seems to be optimum for this system. This experimental approach seems to be useful for the study of mineral metabolism.
Damaging the ossification centre of the proximal epiphysis of the tibia, the articular disc and the metaphysis of rabbits, the effect of injury on growth and the capacity for tissue regeneration during growth were studied radiologically and histologically. The injury penetrating into the metaphysis, directly damaging the articular disc gave rise to a more serious growth disturbance at the proximal end of the tibia than did the injury localized to the epiphyseal ossification centre. Tissue regeneration resulted in a richly vascularized granulation tissue in the injured region, with subsequent spongy bone formation. The hyaline cartilage did not regenerate.
The extent of stress-protection was investigated in 12 patients with previous tibial fractures treated by steel plate fixation. They were examined by computed tomography (CT) scanning one or two days after plate removal. The cortical density and thickness were determined by the CT scans. In the previously plated segment, a significant reduction in cortical density was found, and the reduction was most pronounced in the quadrant directly beneath the plate. The osteopenia did not increase with increasing duration of plate application in excess of one year. No significant differences in cortical thickness between plated and control tibiae occurred. The results indicate that stress-shielding after rigid plating in the human tibia is less pronounced than that previously reported from experimental studies in animals.
High implant-bone stress levels, particularly on rather weak cancellous bone, have been implicated as the predominant cause of aseptic tibial component loosening, the most frequent cause of total knee arthroplasty (TKA) failure. This strain gauge study on six fresh cadaver specimens has revealed that loss of tibial component-cortex contact resulted in a 33%-60% decrease in principal strain values in the proximal tibia. The implication of this finding is that in the absence of implant-cortex contact, the cancellous bone of the proximal tibia must assume the increased load, with the risk of implant loosening and/or sinkage. This study has also demonstrated that the use of tibial components with intramedullary stems was accompanied by marked stress shielding of the proximal tibial cortex over the length of the given stem. This observation refutes the claim that such intramedullary stems are non-weight-bearing and points out the potential risks of cortical atrophy and tibial fracture at the tip of the stem when such implants are used. Although caution must be exercised in extrapolating in vitro laboratory data to clinical practice, this study favors the use of TKA tibial components that rest on the cortical bone and have either no stems or only short intramedullary stems.
We reviewed the cases of seven children with post-traumatic tibia valga in order to determine whether spontaneous improvement of this deformity occurs with growth. The children were between eleven months and six years and four months old at the time of injury and were followed for an average of thirty-nine months after the fracture. The valgus deformity appeared to progress during the period of fracture-healing as well as after union of the fracture, as determined clinically and radiographically. The angulation progressed most rapidly during the first year after the injury, and then continued at a slower rate for as long as seventeen months. Overgrowth of the tibia by as much as 1.7 centimeters accompanied the angular deformity. Adequate clinical correction then occurred spontaneously in six of the seven patients. Because this spontaneous improvement of the deformity usually occurred with growth, we recommend a conservative approach to the management of both the acute fracture and the subsequent valgus deformity.
Intramedullary nailing of the tibia has been used mainly in selected cases of fresh diaphyseal fractures and nonunions. However, with modern variations of the technique, the indications can be expanded considerably. Interlocking nailing has increased the number of fractures suitable for intramedullary fixation. With this technique or with other additional measures, intramedullary fixation can be used after correction osteotomies and for stabilization of metastases and pathologic fractures. When used on correct indications and in the absence of complications, intramedullary nailing is the method of choice for stabilization of the tibia. The advantages are short stay in hospital, short morbidity, early range of motion exercises, and weight-bearing without immobilization in plaster. A prerequisite, however, is that the surgeon be very familiar with the technique, and its indications and complications.
A retrospective review of 37 cases of infantile tibia vara (25 patients) demonstrated a high rate of recurrence following proximal tibial and fibular osteotomy. Sixteen limbs (43%) required a single osteotomy, whereas 21 (57%) required from one to four additional osteotomies. We conclude that in patients with infantile tibia vara, massive obesity, initial osteotomy with Langenskiöld grade III or greater lesions, and initial osteotomy after 4 1/2 years of age are all associated with a high degree of recurrent deformity.
The subjective and objective results of infra-condylar tibia condyle osteotomy are presented, based on a study of 71 cases. Arthroplasty of the knee joint can often be avoided by performing an infra-condylar tibia condyle osteotomy, taking into consideration the contra-indications, in cases of painful (varus) gonarthrosis becoming mainly manifest in a joint compartment, combined with an axis shift. The gait capacity can be improved, the subjective pain symptomatology be diminished and progression of the arthrosis might be avoided. The good results correlate with an optimal correction of the axis condition; in cases of varus gonarthrosis a slight overcorrection beyond the physiological valgus position of 7 degrees and in cases of valgus gonarthrosis a physiological valgus position of 7 degrees should be aimed at.
We determined the dose-response characteristics of a low-voltage, high-frequency, capacitively coupled electrical signal that reverses an established osteoporosis in a rat tibial model with sciatic neurectomy. The electrical signals were delivered by means of stainless-steel gel-coated electrodes. In the first part of the study, the shape (sine wave) and frequency (sixty kilohertz) of the signal were kept constant while the voltage was varied from 0.01 to ten volts, peak to peak. Control osteoporotic and sham osteoporotic animals showed a mean loss of tibial ash weight of 19 and 17 per cent, respectively, twenty-eight days after sciatic neurectomy plus twelve days of no treatment using sham electrodes. Rats that were subjected to 0.25, 0.50, 1.0, 2.5, and 5.0 volts, peak to peak, for twelve days beginning on the twenty-eighth day after sciatic neurectomy all showed mean losses of tibial ash weight that were significantly less than those of the controls. The rats that had a 0.5-volt peak-to-peak signal showed the least mean loss of tibial ash weight (only 6 per cent). We concluded that a capacitively coupled electrical signal, delivered through gel-coated electrodes, can largely reverse an established disuse osteoporosis due to neurectomy in the rat tibia. In the second part of the study, the duty cycles of a sine-wave, sixty-kilohertz, 0.5-volt peak-to-peak signal were varied (12.5, 50, and 100 per cent on), and the wet, dry, and ash weights were determined and compared with those of unstimulated osteoporotic controls. Only the 100 per cent duty-cycle signal was effective in reversing the loss of bone mass in the neurectomized tibiae.
The bone mineral content of the upper ends of the tibia and the fibula was measured in 27 patients with tibia shaft fracture. The bone mineral decreased rapidly after fracture, the loss continuing for about 5 months. Later, towards the end of the first year after the injury, there was a slow restoration of mineral but no return to initial values in most instances. Although the average maximum loss was approximately 45%, only 25% of the initial bone mineral was missing after one year.
Whether or not an effective locking of the medullary nail in transverse direction is achieved after medullary nailing of the tibia, is a moot point in literature. Researchers agree, however, that the essential locking of the nail occurs on the longitudinal axis of the nail. The authors conducted studies with strain gauges measuring the expansion and introduced together with the nail in order to obtain information on the elastic performance of the nail in transverse and longitudinal direction. The curves plotted from the data obtained, present a typical appearance. After the tibia has been properly reamed, a medullary nail of the AO is subjected to both elastic transverse compression as well as slight longitudinal bending after nailing. In case of excessive reaming the transverse elastic effect is only slight. If, on the other hand, reaming is not effected wide enough, the bone may burst open or the nail may undergo plastic deformation.
Eleven proximal pseudarthroses of the tibia and elevated osteotomies of the head of the tibia were treated by fitting a condylar plate; this was done at two hospitals in Berlin and Bayreuth in the course of the past ten years. In all osteosyntheses, osseous reconstruction was achieved within a favourable time. Although mounting is technically intricate, it yields immediate or at least early exercise stability.
A scintigraphic study of the human tibia in the early stages following fracture of the shaft was carried out to investigate the condition of the blood supply of the main fracture fragments. Using a gamma camera and 99mTc-MDP, scintigraphs were obtained from less than 24 hours to 21 days after injury. A generalized increase in tracer uptake was found in the tibia in all cases. In some cases very early after injury there was an additional local increase at the fracture site. In 10% of cases "cold spots" were observed, which may indicate an impaired blood supply to bone tissue adjacent to the fracture. Neither the presence of a "cold spot" nor any other scintigraphic feature could be correlated with the progress or time to fracture union.
Eight patients with congenital pseudarthrosis of the tibia had a Syme amputation and were followed for an average of 5.9 years. The average age at amputation was 8.2 years, and an average of 3.8 surgical procedures were performed prior to the amputation in each patient. None of the pseudarthroses healed, but in spite of that the Syme amputation can be recommended when amputation is necessary. With a simple orthosis, the child can then engage in normal activities. The operation provides a longer stump than do conventional amputations, as well as better skin coverage and more potential for further growth of the tibia from the distal epiphysis.
A rare case of thrombosis of the popliteal artery due to an exostosis of upper end of tibia is reported. It is rare for exostoses to develop at the upper metaphysial region of the tibia, rare fore vascular complications to develop and particularly rare for these to consist of thromboses. This lesion is a differential diagnosis in young adults with lower limb ischemia. Follow up of these exostoses should be by Doppler, after dynamic arteriography to serve as a reference. Surgical treatment should be adapted to the degree of functional disability and the course of the exostosis or the complications it provokes.
Length data for the tibia as gained at the Fels Research Institute for the Study of Human Development and published by Gindhart (1976) are used for mathematical formulation following the method set up by the author for the representation of human length growth and recently applied to the radius development. The data for the tibia leave smaller room for the validity of the short term power function characteristic for younger age. Difficulties were encountered but overcome for the growth function proper (Sager 1981 a), whilst some uncertainties remain for the growth spurt of the female due to irregularities in the basic material.
Deformities of the leg and ankle may result from growth abnormalities of the tibia and fibula. Measurements of the distance between the proximal tibial and fibular physes, the distal tibial and fibular physes, and the angle between the long axis of the tibia and the distal tibial physis and talar dome were made to determine the changes that occur during normal skeletal development. These measurements demonstrate that early detection of growth discrepancy is possible.
Three commonly used bone cements were inserted into tibiae from human cadavers to investigate techniques for optimal intrusion with manual pressurization. In each tibia the medial plateau was cleansed by pulsating water lavage, and the lateral plateau was cleansed by syringe only. Acrylic was inserted at one-minute intervals through four minutes, at which time intrusion decreased steeply. Intrusion was superior in bone prepared by pulsating lavage. Mixing the acrylic for no longer than three minutes prior to insertion by manual pressurization into bone prepared by pulsating lavage is suggested. Clinical use of this technique has improved intrusion, as evidenced by postoperative roentgenograms. As compared with interfacial strengths and depth of intrusion as reported in the literature, the penetration achieved with this technique gives an optimal depth of intrusion (2-4 mm) for adequate strength of the bone-cement composite. A new photographic computer technique is introduced for study of the intrusion of methylmethacrylate into bone. Differences in bone density can be accounted for by this technique, and the correlation coefficient to direct bone biopsy is 0.92.