We present key information from international registries in relation to primary total hip arthroplasty. The specific questions of interest include which bearings are superior in total hip arthroplasty (THA), which fixation types are optimal, do any specific implants perform better than others, and what is the latest update in the hip fracture setting? This is a comprehensive review of the major English-speaking hip arthroplasty registries across the globe. Key trends and developments in implant performance are identified and presented in the current article. Key points from review of all registries confirm that ceramic-on-polyethylene and metal-on-polyethylene continue to be the commonest bearings. The use of cemented femoral stems is increasing across most regions. Hybrid fixation is now the commonest fixation method in the UK for the first time in registry history. Uncemented femoral stems have a higher early revision rate for periprosthetic fracture than cemented stems across most regions. Dual mobility (DM) bearings are increasing in use and show higher early revision rates than unipolar bearings-they tend to be used for more complex indications (fracture/tumor/revision) and show similar revision rates to unipolar bearings when used exclusively in primary elective THA for osteoarthritis. We present current trends in THA based on current registry data from across the globe. Clinical signals of concern are emerging for THA uncemented femoral stem fixation and DM bearings in specific clinical contexts. These signals should be monitored across the literature in order to reduce the overall revision burden.

BACKGROUND: Cranioplasty is a common procedure in neurosurgery. However, cosmetic and neuroprotective reconstructions are necessary after cranioplasty. Treatment of patients with a meningioma with bone infiltration requires removal of the tumor-infiltrated bone and subsequent cranioplasty. We report an efficient technique for cosmetic and neuroprotective reconstructions using a custom-made ultra-high-molecular-weight polyethylene cranial plate (SKULPIO, Kyocera Medical, Kyoto, Japan) in a single-step surgery involving tumor removal and skull reconstruction.
METHODS: We present 2 illustrative cases of a 49-year-old female with a right frontal convexity meningioma and 69-year-old male with a bilateral parasagittal atypical meningioma, both involving extensive skull invasion. We preoperatively planned craniotomy size to facilitate the removal of the tumor-infiltrated skull bone using the patients\' 3-dimensional cranial models followed by the construction of a custom-made cranial plate. After tumor removal, we drilled out the outer table and the diploe of the cranial edge until the custom-made bone plate accurately fit the bone defect. Finally, the cranial plate was fixed using titanium plates and screws.
RESULTS: Postoperative magnetic resonance imaging for each case revealed total meningioma removal and an aesthetically reconstructed skull. Using this technique, precise adjustment of the cranial edge to the plate contributes to a gapless and aesthetic reconstruction. Furthermore, the intact inner table of the skull firmly supports the custom-made bone plate.
CONCLUSIONS: This technique involving the placement of a custom-made cranial plate during a single-step surgery was found to be efficient for cosmetic and neuroprotective reconstructions.

Among the bearing surfaces involved in a total hip arthroplasty, ultra-high molecular weight polyethylene (UHMWPE) is the weak link. It is submitted to the friction of a harder bearing, producing wear particles, which, in turn, initiate an inflammatory reaction ultimately leading to osteolysis. This kind of bone deterioration sometimes turns out to an aggressive granuloma and may provoke implant loosening. Wear resistance of UHMWPE depends on its molecular weight and crystallinity. Some steps of the manufacturing process were improved to optimize its tribological properties and to slow down degradation resulting from mechanical (abrasion) and chemical (oxidation) phenomena. Its preparation and conservation must be performed in an inert atmosphere, i.e. without ambient oxygen. Its resistance to abrasion depends on its cross-linking degree. Its cross-linking rate was observed to increase proportionally to the irradiation doses, improving its wear resistance. However, its mechanical properties are impaired and moreover, it becomes oxidation sensitive. It is therefore necessary to submit it to a thermal treatment to eliminate free radicals that were produced during irradiation. More recently impregnation by vitamin E, a powerful anti-oxidant product, was proposed to preserve the polymer from in vivo oxidation while maintaining its mechanical properties. We raised the hypothesis that last-generation UHMWPE could offer the same wear resistance as the most performing bearings (ceramic-on-ceramic). Recent clinical results confirm the tribological performance of highly crosslinked UHMWPE in vivo. However, it remains to be seen whether this excellent wear resistance would persist under eccentric load such as edge loading, and if, in the long run, this kind of bearing proves capable of reducing the risk of osteolysis in young and active patients.

Wound dehiscence is the separation of a wound along surgical sutures. A 57-year-old, otherwise healthy mechanic presented with a large open wound of >1 month duration on his left hand. His wound had dehisced after treatment that involved cleansing, surgical sutures, and oral antibiotics. He presented with a 5.0 cmx0.7 cmx0.3 cm lesion through the palmar creases of the hand with edema around the fourth and fifth digits and a callous formation around the distal portion of the wound. The wound had scant serosanguinous drainage and some induration at the periwound area, as well as a moderate foul odor. Tendons were not affected, but function was limited, the hand was painful, and the patient had been unable to work. Treatment was initiated with twice-a-week immersion of the hand in hydrogen peroxide diluted with water subjected to high-voltage pulsed current electric stimulation (HVPC). The wound was dressed with silver-containing dressings secured with stretch gauze and a compression garment. The wound was completely closed after 9 visits (35 days). No functional limitations of the hand or fingers, no cosmetic defect, and no wound recurrence were noted 9 months after healing. Although uncommon, dehisced wounds, especially in certain anatomical locations such as the hand, can be difficult to heal and may cause long-term problems with functioning. The treatment combination facilitated expedient healing of this dehisced hand wound. Research is needed to help elucidate the observations from this case study.

A severe abrasion occurred at the stem taper 13 years after total hip arthroplasty. The bearing couple was 28 mm ceramic on polyethylene. The ceramic head had almost no damage, whereas the stem taper had severe damage. An ectopic bone probably contributed to the abrasion. The ectopic bone had grown to restrict the normal motion in the bearing couple and all stress and torque seemed to concentrate in the junction until the junction obtained mobility instead of the original bearing couple.

暂无摘要。

Polyethylene liner fracture is a risk associated with the use of highly cross-linked UHMWPE. We performed a review of the voluntary reports of fractured liners to the US Food and Drug Administration to determine if any risk factors could be identified. There have been 74 reports of fractured Trilogy, Longevity liners to the US Food and Drug Administration since 1999. Most cases utilized small acetabular shells (≤54 mm) combined with large diameter heads (≥36 mm). Liners less than 7 mm thick at the weight bearing or 4.8 mm thick at the rim should be used with caution. At revision surgery, malpositioned shells should be revised and the use of a thin liner should be avoided.

OBJECTIVE: To report a rare case of arrested root formation of permanent incisors in a young boy with mixed dentition and its management.
BACKGROUND: Traumatic injury to a primary tooth may damage the underlying permanent tooth germ and affect its development. The extent of the malformation depends upon the developmental stage of the permanent tooth and the intensity of trauma. Discoloration and hypoplasia of the crown, dilaceration, root angulation and disturbances in eruption are commonly seen developmental disturbances following trauma. However, partial or complete arrest of root formation is a rare developmental sequela of trauma to primary teeth. Attempt should be made to retain these natural teeth during the mixed dentition period.
METHODS: A case is presented of a young boy with rare occurrence of arrested root formation of permanent mandibular incisors, following trauma to the primary predecessors. Clinically these teeth exhibited mobility and radiographic examination showed absence of root formation in relation to the incisors. The treatment plan was to retain the natural permanent teeth for a maximum period and to stabilize them until a more permanent replacement could be carried out. As the patient had mixed dentition, immediate stabilization was done using fiber reinforced splint until further definitive treatment is carried out. Early diagnosis of developmental disturbances in permanent teeth resulting from trauma at a young age is necessary. Regular follow-up appointments, through clinical and radiographic examination and timely intervention may minimize or even avoid harm to the developing tooth.

Restorative dentistry is continually changing, with ground-breaking treatments developing based on new materials, techniques, and technologies. Composite materials are a leading example, and the introduction of fiber reinforcement has further increased the possible uses of composites in restorative dentistry. Maintaining arch length during primary, mixed, and early permanent dentition is essential for the development of occlusion. In an effort to prevent future problems, appliances may be placed to retain space resulting from early loss of teeth. In case of primary teeth loss, fixed space maintainers are being used, but these are time consuming to fabricate, and incorporated wires may lead to soft tissue trauma. This clinical case uses fiber-reinforced composite as a space maintainer, thus reducing the time required to complete treatment. In spite of best efforts of practicing dentists, there still remains a large percentage of the population who do not present for treatment, except with pain or other condition. Unfortunately some of those individuals are children, who are not in a position to make the difficult decision to visit the dentist independently. Often by the time they are examined, there is no chance of saving the involved tooth, necessitating extraction and space maintenance. To prevent closure of space and arch length deficiency, appliances may be placed to retain space. Different appliances may be used for space maintenance, such as the removable and fixed space maintainers, but they are difficult and time consuming to construct. Also, the attention span of a child patient is insufficient for this treatment protocol. Considering these difficulties, the clinician could choose the option of a space maintainer, which is less time consuming to fabricate, and for which patient acceptance is optimal.

A case of bilateral patellar component failure due to fatigue fracture of the all-polyethylene fixation pegs in a highly cross-linked ultra-high-molecular-weight polyethylene design is presented. To recreate this failure mode, a novel test method was developed to investigate the effects of peg orientation and cement technique on patella fatigue strength under cyclic compression and shear loading. Patellar peg orientation had a minor effect on shear strength, whereas lack of cement in the backside patellar groove had a substantial effect. The shear fatigue strength exceeded in vivo force estimates when the patellar groove was fully cemented. The test results and retrieval analysis suggest that high activity level and inadequate cement fixation of the patellar component may contribute to all-polyethylene patellar component peg fractures.