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Internal fixation of distal radius fractures with dorsal dislocation: pi-plate or two 1/4 tube plates? A prospective randomized study.

BACKGROUND: Severely comminuted distal radius fractures can be treated by different methods. Our routine procedure in dorsal dislocated fractures is the dorsal stabilization with two 1/4 tube plates. The new pi-plate is an other device that matches optimally the anatomy of the distal radius and allows a near half-circumferential dorsal buttress of comminuted intraarticular and extra-articular radial fractures. METHODS: In a prospective randomized study, comminuted distal radius fractures with dorsal displacement were stabilized either with two 1/4 tube plates or with the pi-plate. All patients were reviewed at 1, 3, and 6 months after surgery by thorough clinical examination and standard radiographs of both wrists. Results were analyzed and compared in both groups. RESULTS: Subjective and objective results in the pi-plate group are disappointing. Although optimal anatomic results were achieved, the complication-rate was high (14.3%) and the range of motion was limited. At final review, extension and flexion of the injured wrist had recovered to an average of 67% of the normal, contralateral side. Radial and ulnar deviation were limited to 64%, whereas pronation and supination reached 89% and 87%, respectively. Overall, results were good to excellent only in 56%. In a comparable group of patients with similar fractures and stabilization with two 1/4 tube plates, 82% of patients achieved excellent to good results, wrist motion was significantly better (p < 0.05), and no complications occurred. CONCLUSION: With open reduction, cancellous bone grafting, and internal plate fixation in comminuted distal radial fractures, excellent results can be achieved. In our experience, we cannot recommend the 7pi-plate in its current shape and prefer to stabilize distal radius fractures and dorsal fragment dislocations with two 1/4 tube plates.

Adolescent↗

Role of onlay grafting with minimal internal fixation for occipitocervical fusion in oncologic patients.

The choice of fixation for occipitocervical arthrodesis remains controversial, especially in oncologic patients who need further radiographic evaluation or postoperative radiotherapy. We studied the long-term outcome of 20 patients who underwent occipitocervical fusions using onlay corticocancellous bone graft and wiring, with postoperative halo vest immobilization. Eight of these patients had postoperative radiotherapy for spinal tumors (group I), and 12 patients had occipitocervical fusions for other pathologies that did not require postoperative radiotherapy (group II). All patients had solid arthrodeses; however, there was a difference in the average time to fusion between patients who received pre- or postoperative radiotherapy and those who did not (p = 0.11). At an average follow-up of 54.5 months (range 24-92 months) 15 of 20 patients (75%) had excellent or good outcomes. A high fusion rate can be expected with reasonable intraoperative or postoperative complications.

Adult↗

Experimental evaluation of seven different spinal fracture internal fixation devices using nonfailure stability testing. The load-sharing and unstable-mechanism concepts.

Fracture site immobilization capabilities of seven internal spine fixation systems were experimentally evaluated: Harrington double distraction (plain, supplemented with Edwards sleeves, supplemented with sublaminar wires), Luque rectangle, Kaneda device, transfixed Kaneda device, and Steffee plates. Stability evaluation involved comparing the three-dimensional motion that occurred across an experimentally created L1 slice fracture, and the load resistance of the implants when subjected to axial, flexion, extension, lateral bending, and torsional loads. Each implant was tested on 15 different vertebral segments from 200-250-lb calves. All implants load-shared with the fractured vertebral column to varying degrees. All except the Steffee plate system showed an obvious biomechanical weakness in one or more load modes. The unstable 4R-4bar mechanism configuration of bilevel spinal implants was identified. Mechanism configurations allow free movement with little or no resistance to the applied load until load sharing by the spinal column stops the collapse and resists the applied load.

Animals↗

Internal fixation of unstable fracture dislocations of the proximal interphalangeal joint.

We report a group of 14 patients with fracture dislocations of the proximal interphalangeal joint with fracture fragments of adequate size to allow reduction of the proximal interphalangeal joint and internal mini screw fixation of the bone fragment attached to the palmar plate to the base of the middle phalanx. Three years after surgery, (range 25-52 months) the average total active range of motion of the proximal interphalangeal joint was 100 degrees (range 65-115 degrees) for the acute group (operation within 14 days of injury, n=7) and 86 degrees (range 60-110 degrees) for the chronic group (operation on average 46 days after injury, range 21-120 days, n=7). Longer delay from injury was associated with a decreased total range of motion (P=0.028). Further subluxation occurred in three chronic group patients, one required further surgery. The key to successful treatment of this injury is the re-establishment of joint congruity and early mobilization. With appropriate patient selection, pain free, satisfactory range of motion can be achieved. There is a risk of persistent subluxation or dislocation, particularly if treatment is delayed.

Adolescent↗

A comparison of skeletal stability after mandibular advancement and use of two rigid internal fixation techniques.

PURPOSE: Two different methods of rigid fixation were compared for postoperative stability 6 months after mandibular advancement for treatment of Class II malocclusion. MATERIAL AND METHODS: Sixty (30 + 30) patients from two different oral and maxillofacial units treated for a Class II malocclusion by bilateral saggital split osteotomy (BSSO), and two different methods of internal rigid fixation were prospectively investigated. Two groups (S1, n = 15; S2, n = 15) had bicortical noncompressive screws inserted in the gonial area through a transcutaneous approach, and the other two groups (P1, n = 15; P2, n = 15) had the bone segments fixed with unicortical screws and miniplates on the lateral surface of the mandibular body. Cephalograms were taken preoperatively, 2 days postoperatively and 6 months after the operation. A computer program was used to superimpose the three cephalograms and to register the mandibular advancement and postoperative change both sagittally and vertically. RESULTS: These were minor differences in the advancement and postoperative changes between the four groups, but statistically no significant difference was shown in either sagittal or vertical directions. However, statistically verified differences proved that increasing age was associated with a smaller amount of postsurgical relapse. Low-angle cases (ML/NSL < 25 degrees) had a bigger amount of surgical (P = .0008) and postsurgical (P = .0195) movement compared with the patients in the high-angle group (ML/NSL < 38 degrees). Using a multiple regression test, a positive correlation was also shown between the amount of surgical advancement and the amount of postsurgical instability (P = .018). CONCLUSIONS: This prospective dual-center study indicates that the two different methods of internal rigid fixation after surgical advancement of the mandible by BSSO did not significantly differ from each other, and it is up to the individual operator to choose the method for internal rigid fixation.

Adolescent↗

[Significance of ligamentotaxis for internal fixator osteosynthesis in fractures of thoracic and lumbar vertebrae].

Between 1985 and 1990 104 operations on the lower thoracic and lumbar spine using the AO-internal spinal fixation system were performed. The preoperative computed tomography (CT) scans as well as either the postoperative CT scans or the CT scans taken after implant removal of 41 cases were available for evaluation of the narrowing of the spinal canal and the subsequent fracture reduction by means of computer-aided planimetry. It is shown that a near normal reduction of the spinal canal through ligamentotaxis is achieved for a fracture between T 12 and L 2, whereas for fractures between L 3 and L 5 an incomplete reduction is observed. A correlation between the neurologic deficit and the degree of narrowing of the spinal canal could not be established. Obviously, the damage to the spinal cord is determined primarily through the dynamic forces of the impact. Also no statistical correlation could be demonstrated in our cases of the time interval between accident and operation to the degree of reduction of the fracture achieved.

Humans↗

Indications and techniques of open reduction. Internal fixation of distal radius fractures.

Complex distal radius fractures present in a variety of patterns that differ by the area and degree of involvement of the articular and metaphyseal fracture components. No single method of treatment is appropriate for all fractures. This article discusses the types of fractures that either require or are best handled by formal open reduction and internal or external fixation.

Bone Screws↗

[Study of mechanical properties of shape memory alloy plate for internal fixation of jaws].

Ni-Ti alloy compression mini-plate was developed for rigid bone-fixation in oral surgery. The investigation of the mechanical properties of this plate was performed to obtain basic data for its clinical application. Ni-49.49 Ti (at%) alloy and Ni-49.26 Ti (at%) alloy were used for the specimens. First, transformation temperatures of the alloys were measured to evaluate the effect of heat-treatment temperatures. Secondly, tensile and shape recovery tests were performed on four types of mini-plates, i.e., four-hole regular and long types Ni-49.49 Ti (at%), five-hole regular type Ni-49.49 Ti (at%) and Ni-49.26 Ti (at%). The following results were obtained. 1. Specimens with a heat-treatment at 500 degrees C, for 30 minutes in both compositions showed adequate As points (about 25 degrees C) and Af points (44-50 degrees C) for clinical use. 2. In the tensile and shape recovery tests, the 500 degrees C heat-treated four-hole regular type plate showed better mechanical properties than the 440 degrees C heat-treated one. However, in the four-hole regular type plate without heat-treatment, the shape memory effect was rarely found. 3. The five-hole regular type plate of Ni-49.49 Ti (at%) alloy had the best mechanical properties for clinical application, judging from the amount and the temperature of shape recovery. It is concluded that Ni-Ti shape memory alloy mini-plates should be applied for rigid internal bone-fixation in oral surgery.

Alloys↗

Mechanical testing of the wire clamping characteristics of the Fixclip internal fixation system.

Stainless steel wires (Kirschner's wires) have been used for over 60 years to fix internally a wide range of osteotomies and fractures in bones. Fixclips (Corifix, Cirencester, UK) shaped like winged washers have been used to clamp pairs of K wires of diameters ranging from 0.8 to 3.0 mm to standard orthopaedic screws and to fix bones internally in more than 400 patients. The system has proved to be biologically and mechanically very effective. This paper describes the design and some biomechanical test results of the Fixclip. Preliminary strength tests conducted using a Hounsfield Tensometer show that the pull-out force, reflecting the grip of the clip on the wire, is dependent on the wire size and, throughout the clinically relevant range, increases linearly with increasing screw torque. Changing the surface finish of the clip did not confer any advantage over the existing polished clip in terms of grip strength.

Bone Screws↗

[The surgical repositioning of spondylolisthesis using the internal fixator and a new simple repositioning instrument].

A simple aid for reposition of spondylolisthesis with the Fixateur interne is presented. The modification consists of a metric thread, which is cut in the end of the SCHANZ screw, a fitting butterfly nut and a distance tube. This instrument allows a well-dosed and controlled extension and reposition of the dislocated vertebra in all planes. No other instruments or implants, which may hinder the operation, are necessary. After the reposition the bone graft may be inserted from ventral or from dorsal. The dorsal intercorporal spondylodesis saves time, means a lower trauma for the patient and has the possibility for interfragmental compression.

Bone Transplantation↗

Open reduction and internal fixation of un-united fractures of the distal radius: does the size of the distal fragment affect the result?

Two cohort populations consisting of 13 patients with an un-united fracture of the distal radius in whom the distal fragment had more than 5 mm of subchondral bone supporting the articular surface distal to the site of the nonunion and ten patients with an un-united fracture of the distal radius with a smaller distal fragment were compared. There were no preoperative differences with respect to age, gender, interval between injury and index procedure, preoperative amount of radius tilt, ulnar inclination and ulnar variance, or the preoperative function. Independent of the size of the distal fragment in all patients the distal radius was restored to gain bony union and realignment with preservation of some wrist motion. The length of the follow-up period averaged 30 months for the small fragment group compared with 22 months for the large fragment group. Bony union was achieved in 22 patients. One patient out of the large fragment group failed to heal the fracture and had wrist fusion. At the follow-up examination there were no significant differences in the radiological and clinical outcome between the two groups. No differences were seen on total range of motion of forearm supination and pronation with an average of 135 degrees in the large fragment group and 145 degrees in the small fragment group. Wrist motion revealed no significant differences in the flexion-extension arc, averaging 90 degrees in the large fragment group and 83 degrees in the small fragment group. Total range of motion of radial and ulnar deviation of the wrist was similar, averaging 39 degrees in the large fragment group and 43 degrees in the small fragment group. Grip strength averaged 59% compared with the opposite limb for the large fragment group and 67% for the small fragment group. We believe that the results of reconstruction of un-united fractures of the distal end of the radius for patients in whom the distal fragment had less than 5 mm of subchondral bone supporting the articular surface distal to the site of the nonunion are comparable to the results for patients with a larger distal fragment. Therefore, we believe that surgeons should try to preserve even a small amount of wrist motion and reserve wrist fusion as a final resort.

Adult↗

Calcaneal fractures--open reduction and internal fixation (ORIF).

Although pioneers such as Leriche in 1921 [5] and Judet et al in 1954 [4] introduced screw or plate fixation of the broken calcaneus, surgical treatment using open anatomical reduction and stable internal osteosynthesis only commenced at the start of the 1980s. This treatment was made possible by the introduction of new imaging methods such as CT which allowed better detection of the fracture pathology and provided the basis for new surgical strategies. Since the start of the 1990s, various anatomically shaped steel and titanium calcaneal plates have been available. The Foot and Ankle Expert Group of the AO Foundation together with Synthes USA developed an anatomically shaped interlocking calcaneal plate, which has been available in steel since 2002, and a titaniummolybdenum(15%) alloy version (Mathys) since November 2003. The latter is now being tested clinically in our unit.

Adolescent↗

[Stability of the spine following osteosynthesis with internal fixation. Case report].

Fractures of the first and third lumbar vertebrae were primarily reduced and stabilized with a Fixateur interne (The XII-LIV) and filled with transpedicular bone grafts in a 21 years old girl. Nine months after this injury she fell from the fifth floor sustaining a flexion-distraction fracture of Th XI whereas the lumbar spine as well as the Fixateur interne remained intact. Stabilization by a Fixateur interne was carried out again. This is an example of the broad application of Fixateur interne in lower thoracic and lumbar spine traumatology and for the high degree of stability of the Fixateur system.

Adult↗