Archives of orthopaedic and trauma surgery
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Arch Orthop Trauma Surg · Aug 2013
Reduced head-neck offset in nontraumatic osteonecrosis of the femoral head.
Risk factors for nontraumatic osteonecrosis of the femoral head have in common that they trigger intravascular coagulation and thus lead to devascularization of the femoral head. In part of the patients, however, no risk factors seem to be evident. Mechanical reasons contributing to nontraumatic osteonecrosis have not been discussed so far. We hypothesized that recurrent traumatization of the vessels supplying the femoral head by a cam-type mechanism as in femoroacetabular impingement could add to intravascular coagulation. We, therefore, asked whether structural abnormalities at the femoral head-neck junction indicative of such a mechanism could be observed in radiographs of patients with osteonecrosis of the femoral head. ⋯ A reduced head-neck offset in patients with nontraumatic osteonecrosis of the femoral head may act as a mechanical (co-)factor in developing osteonecrosis of the femoral head.
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Arch Orthop Trauma Surg · Aug 2013
Corrective osteotomy of the distal radius following failed internal fixation.
The purpose of this study was to quantify the clinical and radiographic outcomes after corrective osteotomy for malunions of the distal radius following failed internal fixation. ⋯ The results of this study suggest that the operative correction of a distal radius malunion following an unsuccessful internal fixation can be achieved with outcomes comparable to those reported after initial nonoperative treatment.
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Arch Orthop Trauma Surg · Jul 2013
Randomized Controlled TrialA multi-level rapid prototyping drill guide template reduces the perforation risk of pedicle screw placement in the lumbar and sacral spine.
The method of free-hand pedicle screw placement is generally safe although it carries potential risks. For this reason, several highly accurate computer-assisted systems were developed and are currently on the market. However, these devices have certain disadvantages. We have developed a method of pedicle screw placement in the lumbar and sacral region using a multi-level drill guide template, created with the rapid prototyping technology and have validated it in a clinical study. The aim of the study was to manufacture and evaluate the accuracy of a multi-level drill guide template for lumbar and first sacral pedicle screw placement and to compare it with the free-hand technique under fluoroscopy supervision. ⋯ The method significantly lowers the incidence of cortex perforation and is therefore potentially applicable in clinical practice, especially in some selected cases. The applied method, however, carries a potential for errors during manufacturing and practical usage and therefore still requires further improvements.
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Arch Orthop Trauma Surg · Jul 2013
Case ReportsClosed rupture of flexor tendon by hyperextension mechanism in wrist level (zone V): a report of three cases.
Closed flexor tendon ruptures due to trauma without external wound are rare. When the flexor tendon has excessive loading, failure occurs at the tendon insertion or its origin from the bone. It is likely to result in avulsion fracture rather than rupture of the proper portion of the tendon by forceful grasping with hyperextension. ⋯ On physical examination, these patients could not flex interphalangeal joint of thumb or distal interphalangeal joint of the fifth finger. All patients underwent MRI or ultrasonography to find out the location of loss in continuity of the flexor tendons before the operation. After identifying the location, flexor tendon repair or tendon graft using palmaris longus were performed.
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Arch Orthop Trauma Surg · Jul 2013
Computed tomography assessment of lateral pedicle wall perforation by free-hand subaxial cervical pedicle screw placement.
To present the technique of free-hand subaxial cervical pedicle screw (CPS) placement without using intra-operative navigating devices, and to investigate the crucial factors for safe placement and avoidance of lateral pedicle wall perforation, by measuring and classifying perforations with postoperative computed tomography (CT) scan. The placement of CPS has generally been considered as technically demanding and associated with considerable lateral wall perforation rate. For surgeons without access to navigation systems, experience of safe free-hand technique for subaxial CPS placement is especially valuable. ⋯ Placement of screw through a correct trajectory may lead to grade 1 perforation, which suggests transversal expansion and breakage of the thinner lateral cortex, probably caused by mismatching of the diameter of 3.5 mm screws and the tiny cancellous bone cavity of pedicle. Grade 1 perforation is deemed as relatively safe to the vertebral artery. Grade 2 perforation means obvious deviation of the trajectory angle of hand drill, which directly penetrates into the transverse foramen, and the risk of vertebral artery injury (VAI) or development of thrombi caused by the irregular blood flow would be much greater compared to grade 1 perforation. Moreover, there are two crucial maneuvers for increasing accuracy of screw placement: identifying the precise entry point using a curette or hand drill to touch the true entrance of the canal after decortication, and guiding CPS trajectory on axial plane by the resistant of thick medial wall.