Short Proximal Fragment Research Articles

A short-term functional outcome of proximal diaphysio-metaphyseal fracture of tibia treated with intramedullary interlocking nail in combination with poller screw

Non-articular fractures of the proximal third of the tibia account for 5 to 11% of tibial shaft injuries. Intramedullary nailing for metaphyseal tibial fractures with a shortproximal fragment (unlikediaphyseal tibial fractures) is associated with an increased risk of frontal and sagittalplane malalignment. This can be solved by the use of intramedullary interlocking nail in combination with blocking screws or Poller screws. A series of 20 cases of proximal diaphysis-metaphyseal fracture of tibia treated with intramedullary interlocking nail in combination with poller screw and were followed up regularly till 6months and evaluated using Modified Karlstrom-Olerud Score. Most patients had Excellent score at 6th month follow-up. Our study suggests intramedullary interlocking nail in combination with poller screwis an effective management of proximal diaphysio-metaphyseal fracture of tibia.

Functional outcome of proximal third tibial fractures with intramedullary tibial locking nail and poller screws

Background: Non-articular fractures of the proximal third of the tibia account for 5 to 11% of tibial shaft injuries. Closed management often leads to varus malunion, especially when the fibula is intact. Although intramedullary nailing may lead to valgus malunion, it can be useful for stabilising fractures with proximal fragments longer than 5 to 6 cm. Intramedullary nailing for metaphyseal tibial fractures with a short proximal fragment is associated with an increased risk of frontal- and sagittal-plane malalignment. This can be solved by the use of blocking screws or Poller screws. Methods: 20 men and 15 women aged 20 to 60 (mean, 35.4) years underwent intramedullary nailing supplemented with Poller screws for acutely displaced fracture. 90% of the fractures were caused by road traffic accidents. 29 cases had closed fractures and 6 had grade I or II compound fractures. Clinical and radiological outcome was evaluated. Results: In 32 cases, healing occurred after a mean of 4.2 (range, 3–9) months. In 1 case, there was non-union, which was resolved by bone grafting. One case was mal-united. 32 patients had recovered a full range of knee motion (0o–130o), and the remaining 3 patients attained flexion of 0o to 90o. According to the knee rating scale of the Hospital for Special Surgery, outcome was excellent in 32 patients, good in 2 and poor in 1 at final follow up. Preoperatively, of the 35 cases, 20 were varus, 15 were valgus. The range of varus to valgus was +22o to -10o. Postoperatively, 34 cases had

Outcome of Surgically Treated Fractures of the Condylar Process by an Endoscopic Assisted Transoral Approach

Fractures of the condylar process are frequent. Ideal management of these fractures, as discussed in the literature, is controversial. Some recent meta-analyses have favored open reduction and internal fixation using various approaches. A strictly transoral approach has been described to minimize scarring and risk of facial nerve injury but has restricted visibility. This retrospective study analyzed outcomes of patients with unilateral mandibular condyle fractures who were treated by open reduction and internal fixation through an endoscopic-assisted transoral approach. This study included 40 patients who were operated on from January 2015 through December 2016. All patients underwent surgery for a condylar process fracture using an endoscopic-assisted transoral approach. Fracture classification, demographic, and outcome data were collected. Most condylar process fractures were caused by falls from a height less than 3m. Most were condylar base fractures and classified according to Spiessl and Schroll as Classes I and II. Sixteen patients showed a preoperative malocclusion, whereas 2 patients showed a slight postoperative malocclusion. In cases in which only 1 plate could be placed, the proximal fragment was shorter. A higher Spiessl and Schroll class showed a tendency toward longer operation times. For postoperative outcomes, 1 case of temporary facial palsy was the worst complication (2.5%), 2 cases exhibited minimal occlusal interference (5%), and 1 case exhibited a deviated mouth opening (2.5%). Ramus height was restored in all cases. No chronic pain was found in any cases. It is feasible to treat condylar process fractures in a safe manner using a transoral approach with endoscopic assistance and angled instruments without facial scarring and at a low complication rate. The endoscope improves the restricted visibility of the transoral approach, although a learning curve is necessary. This applies especially to dislocated fractures or to fractures with a short proximal fragment.

Infrapatellar vs. suprapatellar approach to obtain an optimal insertion angle for intramedullary nailing of tibial fractures

During intramedullary nailing of tibial fractures, the insertion angle of the nail is of great importance. When the nail impacts the posterior cortex due to a large insertion angle with a dorsal target course, higher insertion forces are needed, and the danger of iatrogenic fractures increases. Accordingly, the insertion direction should be as parallel as possible to the longitudinal axis of the tibia. We aimed to confirm the hypothesis that intramedullary nailing of tibial fractures can be performed with smaller insertion angles via a suprapatellar approach rather than infrapatellar approach. In 19 human bodies of donors with intact tibiae, we performed intramedullary nailing by both a suprapatellar and an infrapatellar approach. The correct entry point was determined by fluoroscopy. Subsequently, the medullary canal was reamed up to a diameter of 10mm, and a 9mm polytetrafluorethylen tube was inserted instead of a tibia nail. The angle between the proximal aspect of the tube and the longitudinal axis of the tibia was measured using a computer-assisted surgery system. The angle between the proximal aspect of the inserted tube, simulating the tibial nail, and the longitudinal tibial axis was significantly larger when using the infrapatellar approach. We achieved an insertion angle significantly more parallel to the longitudinal axis when using a suprapatellar approach for intramedullary nailing of tibial fractures. Thereby, both the risk of iatrogenic fracture of the posterior cortex and apex anterior angulation of the short proximal fragment can be reduced during intramedullary nailing of tibial fractures.

Transcriptional regulation of the human Liver X Receptor α gene by Hepatocyte Nuclear Factor 4α

Liver X Receptors (LXRs) are sterol-activated transcription factors that play major roles in cellular cholesterol homeostasis, HDL biogenesis and reverse cholesterol transport. The aim of the present study was to investigate the mechanisms that control the expression of the human LXRα gene in hepatic cells. A series of reporter plasmids containing consecutive 5′ deletions of the hLXRα promoter upstream of the luciferase gene were constructed and the activity of each construct was measured in HepG2 cells. This analysis showed that the activity of the human LXRα promoter was significantly reduced by deleting the −111 to −42 region suggesting the presence of positive regulatory elements in this short proximal fragment. Bioinformatics data including motif search and ChIP-Seq revealed the presence of a potential binding motif for Hepatocyte Nuclear Factor 4 α (HNF-4α) in this area. Overexpression of HNF-4α in HEK 293T cells increased the expression of all LXRα promoter constructs except −42/+384. In line, silencing the expression of endogenous HNF-4α in HepG2 cells was associated with reduced LXRα protein levels and reduced activity of the −111/+384 LXRα promoter but not of the −42/+384 promoter. Using ChiP assays in HepG2 cells combined with DNAP assays we mapped the novel HNF-4α specific binding motif (H4-SBM) in the −50 to −40 region of the human LXRα promoter. A triple mutation in this H4-SBM abolished HNF-4α binding and reduced the activity of the promoter to 65% relative to the wild type. Furthermore, the mutant promoter could not be transactivated by HNF-4α. In conclusion, our data indicate that HNF-4α may have a wider role in cell and plasma cholesterol homeostasis by controlling the expression of LXRα in hepatic cells.

Suprapatellar approach to tibial medullary nailing with electromagnetic field-guided distal locking

Closed tibial shaft fractures are the domain of intramedullary nailing. With the introduction of new nail designs and technologies, even small, dislocated distal fragments can be anatomically aligned and safely fixed. Unsolved or to a lesser degree controlled are the problems of distal locking in the freehand technique, which can still be difficult and can lead to a significant radiation exposure, and how to control very short proximal tibial fragments in metaphyseal tibial fractures or tibial segmental fractures, where the proximal fracture line also runs through the metaphysis.By using a suprapatellar approach, i.e. a skin incision proximal to the patella with an entry point into the tibial bone from within the knee at the same site as for a standard infrapatellar approach, and then nailing the tibia in a semi-extended position, i.e. the knee is only flexed 10-20°, the intraoperative dislocation of a short proximal fragment can be avoided. The main indications for semi-extended tibial nailing are a short diaphyseal fragment in an isolated tibial shaft fracture, a segmental fracture where the proximal fracture line is metaphyseal and in patients where infrapatellar soft tissues are compromised.The use of the electromagnetic guidance system SureShot® generates reliable and reproducible results, reduces the operating time and is independent from radiation for distal locking.

Intramedulläre Nagelung von proximalen Tibiafrakturen

Restoration of axis, length, and rotation of the lower leg. Sufficient primary stability of the osteosynthesis for early functional aftercare. Maintaining mobility of knee joint. Bone healing in closed and open fractures. Closed and open isolated proximal tibia and lower leg fractures (AO 42). Extraarticular fractures of the proximal tibia (AO 41 A2/A3). Intraarticular fractures of the proximal tibia (AO 41 C1/C2) in combination with other implants. Segmental tibia fractures (AO 42 C1/C2) with short proximal fragment. Comminuted tibia shaft fractures (AO 42 C3) with short proximal fragment. Very poor general condition (e.g., bedridden). Flexion of knee less than 90°. Infection in the nail's and bolt's insertion area. Infection of the tibia intramedullary canal. Complex fractures of the tibia plateau (AO 41 C3). Open physis. Closed reduction of the fracture. If necessary, use of reduction clamps through additional stab incisions or open surgical procedures. In some cases, additional osteosynthesis procedures are necessary (e.g., compression screws). Positioning of the patient on a radiolucent table or a traction table. Opening of the proximal tibia in line with the medullary canal. Cannulated or noncannulated insertion of the nail with or without reaming of the medullary canal. Control of axis, length, and rotation of the lower leg. Triple proximal interlocking in three different planes with the targeting device. Double distal interlocking. Immediate mobilization of the knee joint. Depending on the type of fracture, mobilization with 20kg partial weight bearing or pain-dependent full weight bearing with crutches. X-ray controls after 3, 6, and 12 weeks and increase of weight bearing depending on the fracture status. In a prospective multicenter study on the stabilization of tibia fractures with the Expert Tibial Nail, 22 patients with proximal third tibia fractures were documented. Seventeen patients could be reviewed clinically and radiologically after 1year. A non-union was registered in 1patient (5.9%), a malalignment in any plane above 5° in 3fractures (17.6%).

V-Jun downregulates the alpha 2 (I) collagen target gene indirectly through Sp1/3

Transformation of chick embryo fibroblasts (CEFs) by the v-Jun oncoprotein correlates with a downregulation of the alpha 2 (I) collagen gene. To investigate whether this gene constitutes a direct target of v-Jun, an analysis of a large proximal fragment of the promoter, extending from position -1080 to +109, was performed. Transient transfections with -1080/+109 and deleted derivatives revealed that a short proximal fragment, -433/+11, is the target for repression by v-Jun. Extensive analysis, conducted in CEFs and in Sp1/3-deficient Drosophila SL2 cells, further showed that (i) high constitutive activity of -433/+11 requires a direct binding of the ubiquitous Sp1 and/or Sp3 transcription factors acting on two distinct motifs, that is, a proximal TCC-rich region and an upstream GC box, and that (ii) repression by v-Jun does not require any direct binding of the oncoprotein to the DNA, but an indirect binding within a v-Jun-Sp1/3-DNA chromatin-associated complex. This situation is reminiscent of a situation previously reported with the tata-less, SPARC (secreted protein, acidic, and rich in cysteine) target promoter that regulates the expression of another extracellular matrix component in the same model of cell transformation. Taken together, these data reinforce the view that, at least in CEFs, v-Jun downregulates a family of direct target genes by binding to the DNA indirectly through Sp1/3.

Subtrochanteric femoral fractures treated with locked intramedullary nails: Experience from 31 cases

We treated 31 proximal femoral shaft fractures, where the trochanteric area was intact, with Grosse-Kempf locked intramedullary nails. There were 19 men and 12 women with a median age of 24 (14-79) years. Sixteen fractures were comminuted and 11 were a component of severe multiple injury. No infections or other serious complications occurred. All the fractures healed within 40 weeks, with 16 results graded as excellent, 7 as good, 7 as fair, and 1 as poor. Six fair results were due to difficulties in aligning the short proximal fragment. One patient with a fair and 1 with a poor result had excessive shortening of the femur. We conclude that locked intramedullary nailing is a good alternative in these fractures and that the static variant is preferable whenever the stability is uncertain.

WIRE FIXATION OF FRACTURES OF THE PROXIMAL THIRD OF THE HUMERUS

A relatively high percentage of fractures of the proximal third of the humerus in which the fragments are completely displaced are difficult or impossible to reduce satisfactorily by manipulation. This is especially true of the fracture-dislocations and of those fractures in which the head of the humerus is also broken into two or more pieces. These fractures are likewise difficult to treat by traction, because the short proximal fragment tends to be abducted and rotated outward while the pectoralis major and subscapularis muscles tend to draw the proximal end of the distal fragment inward and forward. When traction is applied in abduction, the proximal end of the distal fragment is drawn forward and downward by the pectoralis major and latissimus dorsi muscles (fig. 1 A ). On account of the difficulties mentioned, it is my custom to treat these fractures by open reduction, frequently without even attempting treatment by closed manipulation