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PubMed1998

[Importance of internal fixation for talar neck fractures].

Fracture of the talus, which articulates with 4 other bones in the ankle and foot, must be properly diagnosed, classified and treated to avoid the common complications of post-traumatic osteoarthritis and avascular necrosis. Knowledge of blood supply and anatomy is imperative, since the surgical approach must not damage the few vascular structures that remain intact after the trauma. We present 5 cases of fractures at the neck of the talus. All underwent internal fixation, 1 after closed reduction and 4 after open reduction. In all the results were satisfactory, although 1 patient developed avascular necrosis of the talar body.

Adolescent↗
PubMedDate not supplied

[In-vitro measurement of loading using an instrumented vertebral internal fixator].

Only little is known about the loads acting on internal spinal fixation devices. The forces and moments for different external loads were now measured using instrumented implants. Measurements were performed on intact cadaver spines and after a corpectomy. Additionally the influence of the mounting accuracy on the distribution of the loads in the fixators was investigated. It could be shown that the implants are not loaded symmetrically. After a corpectomy the loads on the implants are significantly higher than for an intact spine.

Aged↗
PubMed1989

Stress shielding effect of rigid internal fixation plates on mandibular bone grafts. A photon absorption densitometry and quantitative computerized tomographic evaluation.

The use of rigid internal fixation reconstruction plates in combination with bone grafts provides many advantages in mandibular reconstruction. These advantages include ease of adaptability at the time of surgery as well as immediate postoperative function for the patient. Disadvantages may include a "stress shielding" or disuse osteoporosis effect on the underlying bone graft as a result of the rigidity of the reconstruction plate. This study evaluated the stress shielding effects on bone grafts in primate mandibles. Bilateral bone grafts stabilized with rigid fixation plates were performed in 4 Macaca fascicularis monkeys. Three months after the bone grafting procedure one plate was removed from each monkey. The monkeys were then killed 1, 4, 6 and 8 months after plate removal. Photon absorption densitometry and computerized tomography were used to evaluate stress shielding. The results of this study indicate that the stress shielding effect occurs if the plate is not removed from the area of bone grafting postoperatively.

Absorptiometry, Photon↗
PubMed1994

A biomechanical evaluation of three forms of internal fixation used in ankle arthrodesis.

A biomechanical study was undertaken to evaluate the relative stability of three types of internal fixation used for ankle arthrodesis. Crossed screw fixation, RAF fibular strut fixation, and T-plate fixation were tested in 30 cadaver ankles using an MTS machine. T-plate fixation consistently provided the stiffest construct when compared with the other types of fixation. Failure occurred by distraction of bony surfaces, posterior to the plane of fixation, in the crossed screw and RAF groups. In contrast, failure in the T-plate group occurred through compression of bone anterior to the midcoronal plane of the tibia. Although the stability of fixation is only one factor in determining the success or failure of ankle arthrodesis, the results of this study would support T-plate fixation over the other forms tested.

Ankle Joint↗
PubMed1992

Uppsala screws or Hansson pins for internal fixation of femoral neck fractures? A prospective study of 180 cases.

In a prospective randomized trial, two methods of internal fixation of femoral neck fractures were compared. Totally, 179 patients with 180 fractures were treated with either two Uppsala screws (n 96) or two Hansson pins (n 84). In all, 130 fractures were primarily displaced (Garden stages III and IV), whereas 88 percent of the fractures in both groups were well reduced. The patients were followed clinically and radiographically for 1 year. Thirty-six patients died within 12 months after the operation. The functional results and the incidence of segmental collapse and nonunion did not differ between the groups. However, at the 4-month follow-up, 2 of 59 of the Garden's stages III and IV in the Uppsala-screw group were found displaced, whereas the corresponding result in the Hansson-pin group was 9 of 52 (P = 0.03).

Adult↗
PubMed2004

[Key points about atlanto-axial internal-fixation and fusion using Gallie's technique].

OBJECTIVE: To study the clinical problems about posterior atlanto-axial internal-fixation and fusion for atlanto-axial instability or dislocation. METHODS: Surgical treatments of 138 cases with atlanto-axial instability or dislocation were reviewed. There were 62 cases of odentoid malformation, 54 cases of odentoid fracture or rupture of transverse ligament, 22 cases of subluxation and rotation. All cases were treated using Gallie's technique. Six cases were also fixed with transarticular screws, and protected with Philadelphia collar. Other patients were fixed with plaster paris brackets. The followed-up period was 1 to 12 years with an average of 3 year and 5 months. RESULTS: According to Sumi's criteria, excellent 70 cases (50.7%), good 40 cases (29.0%), fair 15 cases (10.9%), poor 13 cases (9.4%). 9 cases with bone graft postponed fusion were cured by enhance external-fixation. 2 cases with nonunion were treated with revision surgery. Complication of cord injury happened in 1 case. CONCLUSION: Gallie's fusion technique is an effective method to manage the atlanto-axial instability or dislocation. Skull distraction before operation and reliable external-fixation post operative are important assistant measures. Key points for successful operation are careful wiring or cable traversing, decortication of posterior arc of C1, and maintaining the physiological height between C1 and C2 posterior arc. Indications and objectives should be conformed before revision surgery for failure cases.

Adolescent↗
PubMed1986

Fusion of the lumbar and sacral spine by internal fixation with screw plates.

From 1972 to 1982, 455 patients had arthrodesis and other operations with screw-plate internal fixation of the lumbosacral spine. Of these 455 patients, 440-413 of whom had had spinal fusion and 27 of whom had undergone pars interarticularis reconstruction--were evaluated for a mean follow-up period of 31.6 months. The principal indications for single-stage posterior fusion, which was performed in 266 cases, were severe degenerative joint disease and painful spondylolysis, while the primary indications for combined anterior and posterior repair, which was undertaken in 145 cases, were spondylolisthesis and malignant tumors. Two cases had single-stage anterior fusion. Initial anterior surgery was performed to achieve reduction of vertebral displacement, while the posterior approach was carried out to allow for fusion of the posterior joints and for osteosynthesis; specially-designed screw plates were attached to the pedicle for this purpose. The rate of solid fusion was 97.4% in the single-stage posterior procedures and 100% in patients who had been treated by a combined approach. Only five neurologic complications were encountered out of the combined approach (two regressive cauda equina syndromes and three regressive L5 nerve root pareses), and these occurred early in the investigation, when the technique was still being refined. Only six cases of single-stage posterior approach sustained a monoradicular lesion that subsided after the offending bone screw was removed. Such complications can be avoided if the surgeon is thoroughly familiar with the techniques described.

Adolescent↗
PubMed1991

[A new design of internal fixation for scoliosis-multi-screw fixed distractor-compressor via the vertebral pedicle and its clinical application].

A new scoliotone, which is made up of screws, sockets, clamps, distraction rod and compression rod, was used stabilize immobilization of the spine in 10 cases. This scoliotone can produce free motion in three different levels, and has a strong power of fixation, distraction, compression and antitraction. In 10 cases when the patient's spinal curvature (cobb's angle) was less than 50 degrees, the average range of correction was 78.2% and the correction rate of kyphosis peak was 90%. When the spinal curvature was between 50 to 100 degrees, the average range of correction was 68.2%, and the correction rate of kyphosis peak was 87.7%. If the spinal curvature was more than 100 degrees, the average range of correction rate of kyphosis peak was 82%. After the operation, the patient might not be immobilized. In this paper, the biomechanical features of the vertebral arch, internal fixation and correction of kyphosis peak were discussed.

Adolescent↗
PubMed1988

Fracture of the femoral neck after internal fixation.

A case of femoral neck fracture despite the presence of a previously inserted sliding screw and sideplate is reported. Internal fixation in itself did not prevent subsequent fracture. A critical factor in the mechanism of this fracture was the patient's underlying disease, felt to be alcoholic osteomalacia.

Aged↗
PubMed1995

Stability and effect on the soft tissue profile of mandibular setback with sagittal split osteotomy and rigid internal fixation.

The stability and the effect on the soft tissue profile of mandibular setback with sagittal split osteotomy and rigid internal fixation was studied prospectively in 29 consecutive patients, 17 to 55 years old, who had mesial occlusion. Profile cephalometric radiographs were taken immediately before and short after surgery as well as 14 months postsurgically. The mean setback of the mandible 1 to 8 days after surgery was 6.0 mm. On average, there was also a small decrease in the anterior facial height. The setback relapsed an average of 1.1 to 1.3 mm, so that at the follow-up the mean net effect was 80%. In eight patients, however, the mandible had retruded slightly further. During the follow-up period there was a further small decrease in the anterior facial height. The net effects on the labial fold and the soft tissue chin were closely correlated with those on their underlying hard structures. On average, the labial fold and the chin followed the hard structures to 106% and 107%, respectively. The mean net effect for the lower lip was only 88% of the setback of the mandibular incisor. The soft tissue facial height followed the decrease in the skeletal facial height to 60%. The setback procedure also affected the upper lip, which, on average, retruded and lengthened 1.0 to 2.0 mm.

Adolescent↗
PubMed2005

Correction of multiplanar hindfoot deformity with osteotomy, arthrodesis, and internal fixation.

Multiplanar deformity of the hindfoot is among the most daunting deformities of the foot and ankle to correct. Deformity correction must attempt to fix the overall orientation of the foot, and prior surgical procedures, arthritic conditions, neurologic abnormalities, musculotendinous insufficiency, and patient goals must be considered. The procedure must relieve pain, arthritis, or instability of the hindfoot and ankle, as well as pressure overload of the lateral foot, midfoot, and/or forefoot. The foot should achieve a plantigrade position that allows for easier shoe fitting and provide a stable plaform for weight bearing. When multiple deformities are present, a staged approach to surgical correction is needed. The goal is to create a plantigrade and stable hindfoot first, and then focus on the forefoot. Multiplanar and severe deformities require a variation of basic arthrodesis and osteotomy techniques. Properly placed wedge excisions and soft-tissue releases will enable a plantigrade correction. In some situations, even arthrodesis is insufficient to correct deformity, and residual hindfoot varus or valgus must be corrected with various types of osteotomy of the calcaneus. Osteotomies of the mid-tarsal region can be considered for residual pes cavus, forefoot supination, adduction, or abduction. An algorithmic approach is used in which the hindfoot is corrected first,followed by the midfoot and forefoot. Correction using multiplanar cuts and internal fixation to establish a plantigrade foot provides the best opportunity for a successful result.

Ankle Joint↗
PubMed1990

Treatment of trans-scaphoid perilunate dislocations by internal fixation with the Herbert screw.

Thirteen patients with 14 dorsal trans-scaphoid perilunate dislocations were treated by open reduction and internal fixation of the scaphoid using a Herbert screw. The follow-up evaluations took place after a mean of 18 months. These perilunate dislocations were only trans-scaphoid in ten wrists, trans-radial styloid and trans-scaphoid in three and trans-scaphoid and trans-capitate in one. Based on Cooney's clinical scoring system, the scores of our series were two excellent, six good, five fair and one poor. This suggests that the Herbert screw can offer satisfactory results in the management of trans-scaphoid perilunate dislocations, despite its technical difficulties.

Adult↗
PubMed1987

Stability of mandibular advancement osteotomy using rigid internal fixation.

Forty-three patients who underwent surgical lengthening of the mandible using an inverted L osteotomy, bone grafting, and rigid internal fixation between the mandibular segments were evaluated by retrospective cephalometric analysis for longitudinal skeletal and dental changes. Postoperative response (means = 1 year 9 months) was found to demonstrate a high level of stability with some individual variability. No propensity for relapse was observed in any postoperative time interval. Condylar repositioning postoperatively appeared to be an important factor in those patients who exhibited any relapse tendency. Overall postoperative stability of this surgical/fixation technique appears to be significantly improved compared with previously documented techniques.

Adolescent↗
PubMed1996

[A new method of osteosynthesis in proximal humeral fractures: a new internal fixation device. Apropos of 17 cases followed over more than 2 years].

PURPOSE OF THE STUDY: The authors describe a new internal fixation device, and report on 17 proximal humeral fractures managed with this technique. MATERIAL AND METHODS: The fracture patterns, using Neer's classification were: 9 displaced three-part fractures, 4 displaced four-part fractures and 4 interior fracture dislocations (mean age of the patients: 70 years). The device is a two-part titanium device. The humeral component has a long vertical stem cemented in the humeral shaft; and a short proximal portion set at an angle of 135 degrees on the stem, with a neck and a Morse taper cone. The other part is a crown-shaped stapple, whose base is a perforated disk with a central Morse taper socket. The rim of the crown has five prongs which, together with the central socket, are impacted in the cancellous bone of the humeral head. The taper of the humeral component is inserted into the central socket of the stapple to provide fracture fixation. Tuberosities are reattached to the shaft with non absorbable sutures. RESULTS: Mean follow-up was 29 months. The global ratings were as follows: 4 excellent results, 6 good results, 4 fair results, 3 poor results. Mean active forward flexion: 100 degrees, and mean active external rotation 22 degrees. After exclusion of the 4 fracture-dislocations, the global rating became: 4 excellent results, 5 good results, 3 fair results, 1 poor result. Mean active forward flexion: 110 degrees and mean active external rotation: 31.5 degrees. There were no case of avascular necrosis in 13 patients. Complications requiring surgery occurred in one case: an upper protrusion of the stapple which required replacement of the stapple by a prosthetic humeral head. Other complications included: 2 asymptomatic partial protrusions of the stapple, 2 complete and two partial avascular necrosis in fracture-dislocations. DISCUSSION: Except for the fracture-dislocations our device confers several major benefits. The humeral head is preserved. Typical problems associated with joint replacement (dislocations, loosening, glenoid degeneration) are avoided. Humeral head conservation enhances healing of the tuberosities. Fixation could always be obtained, regardless of the complexity of the fracture pattern. An hemiarthroplasty (e.g. in case of avascular necrosis) is possible by the modular design of the device.

Adult↗
PubMedDate not supplied

First metatarsophalangeal joint arthrodesis: a new technique of internal fixation by using memory compression staples.

A prospective clinical study of first metatarsophalangeal joint arthrodesis using memory compression staples is presented. In 27 patients, 30 feet underwent surgery. There were 24 women and 3 men, with a mean age of 61.2 years. Two memory compression staples were used at right angles to each other to achieve compression at the fusion site. Postoperatively, patients were allowed full weightbearing in a rigid-soled shoe. Subjective assessment was performed with a standard questionnaire, which included questions regarding level of pain, ambulation, and patient satisfaction. Objective assessment was performed by a clinical and included a radiographic examination. There was a postoperative reduction in the pain score from 4.6 to 1.6 (P < .0001). Ambulation ability improved from 4 to 2.5 (P < .0001). Patients reported 86.6% excellent to good results, and 96.7% achieved radiographic fusion at an average 8.2 weeks. The only significant postoperative complication was a single nonunion. The authors advocate memory compression staples for the internal fixation of first metatarsophalangeal joint arthrodesis. The implant is low profile, and postoperative cast immobilization is not required. The use of this device has a predictable success rate comparable to previously reported methods.

Arthrodesis↗
PubMed2003

Immuno-inflammatory tissue reaction to stainless-steel and titanium plates used for internal fixation of long bones.

The immuno-inflammatory responses to stainless-steel (21 implants in 20 patients) and titanium plates (22 implants in 20 patients) used in the treatment of long bone fractures were studied immunohistochemically. All fractures healed without complications. In the soft tissue adjacent to the surface of the implants a dark discolouration of the tissue was visible in 18/21 stainless-steel and 20/22 titanium plates. Tissue specimens of all patients contained positive staining for macrophages (CD68-positive cells). Serial sections showed that the majority of cells were found to express the HLA-DR molecule indicating their activation. Many of the macrophages were surrounded by clusters of T-lymphocytes (CD3-positive cells). 17 out of 21 steel specimens and 15 out of 22 titanium specimens showed the infiltration of moderate amounts of cytotoxic T-lymphocytes (CD8-positive cells). Moderate amounts of B-lymphocytes (CD79alpha positive cells) were evident in four patients with steel and six patients with titanium implants. The results of the present study clearly demonstrate the presence of a marked inflammation and tissue reaction in the soft tissue covering stainless-steel and titanium plates used for internal fixation of fractures of long bones independently from the material used.

Adult↗
PubMed1986

Posterior cervical fusion with rigid internal fixation.

Rigid fixation of the posterior cervical spine offers definite advantages over conventional wiring techniques. These advantages are emphasized in certain high-risk groups of patients, including those with multiple-level traumatic instability, cervical deformities, and unresectable anterior tumor involvement. Early fusion with minimal external fixation is another important advantage. The focus of this article is the concept of rigid internal fixation of the posterior cervical spine and the application of specific techniques used to achieve this goal.

Adolescent↗
PubMed1998

An algorithm for preoperative prediction of reoperation risk after internal fixation of femoral neck fractures.

An algorithm was designed for preoperative prediction of the risk for reoperation, and the mortality risk, after internal fixation of femoral neck fractures. Out of 51 reviewed studies of femoral neck fractures, eight met specified inclusion criteria such as low dropout rates, a minimum of ten surgeons performing the surgery, a minimum of 2 years follow-up, and a standard age, sex, and Garden class distribution. Five of these studies were used for the construction of the algorithm, and the remaining three for testing the specificity and sensitivity of the algorithm. A separate analysis of the influence of age on the reoperation rate was also performed. In the analysis of 399 reviewed cases of femoral neck fractures, the specificity for the algorithm in predicting the risk for reoperation was 96%, and the sensitivity was 51%. The positive predictive value for the algorithm in predicting the risk for reoperation was 77%, which was three times higher compared to the commonly used predictors age and Garden class (positive predictive value 25%). For prediction of the mortality risk the positive predictive value for-the algorithm was 57%.

Aged↗