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71.

Purpose

Alterations in patellar height after high tibial osteotomy are found in many instances. Fibrosis of the tendon is implicated as the cause of the mechanism of patella lowering. This study aimed to determine the relationship between the position of the patella and the histopathological findings at the patellar tendon after high tibial osteotomy.

Methods

Nineteen knees in seventeen patients who were consecutively hospitalised for implant extraction are studied. All of the patients had previously undergone closing wedge osteotomy by the same surgeon at the same department. The median follow-up time is 15 months (range: 11–35). Five patients who all underwent high tibial osteotomy at the same time are also included in the study as a control group for histopathological evaluation. All of the patients are evaluated radiologically, patellar tendon biopsies are taken during the operation, and histopathological analyses are performed.

Results

The shortening of the patellar tendon is statistically significant (P < 0.05). The severity of the vascularisation, inflammation, and fibrotic change observed at the distal part of the tendon is evident. However, there is no statistically significant correlation between these findings and the degree of shortening.

Conclusions

The shortening of the tendon occurs as a result of adherence in the distal part of the tendon. It would appear that it is this shortening that causes the difficulties encountered during arthroplasty surgery of osteotomy patients, and not patella infera.

Level of evidence

Retrospective study, Level II.  相似文献   
72.
Tomak Y  Kocaoglu M  Piskin A  Yildiz C  Gulman B  Tomak L 《Injury》2005,36(5):635-643
Forty-two geriatric patients who had an intertrochanteric fracture were treated with a semicircular modification of the Ilizarov frame designed by Cattaneo and Catagni between January 1997 and September 2001. Twenty-five of the patients were female, 17 male. The average age of the patients was 77.5 years (range, 63-99). No intraoperative complication occurred. Deep pin-track infection was found in four patients and varus deformity was observed in two patients and shortening of less than 2 cm in 10 patients. Fixator removal was achieved in a mean time of 12 weeks (range, 10-18). No implant failure, refracture or stiffness of knee and hip joint movements was recorded. We concluded that the treatment of intertrochanteric fractures of the elderly patients with our modification provides significant advantages such as minimal operative and anaesthetic risks, no blood loss, early weight-bearing, short hospitalisation time and rapid union time.  相似文献   
73.
PURPOSE: The purpose of this study was to determine whether the continuous horizontal mattress suture technique can replace the continuous simple suture technique and to compare the results with other microvascular suture procedures. METHODS: Sixty-four femoral arteries of 32 Sprague-Dawley rats were used in this study. The animals were divided equally into 4 groups with 16 anastomoses in each group. The arteries (0.8-1.0 mm diameter) were anastomosed by using the continuous horizontal mattress suture technique in group I, interrupted horizontal mattress suture technique in group II, simple interrupted suture technique in group III, and simple continuous suture technique in group IV. At the end of the anastomosis time, leakage, and patency were assessed and graded in all groups. On the 14th day after surgery the rats were killed and 5 patent specimens from each group were examined under light microscopy for histology. One specimen from each group was prepared for scanning of the endothelial surface under electron scanning microscopy. RESULTS: Group I anastomoses were performed the most quickly. Groups I and III anastomoses had 100% patency rates. Under light microscopy the edge eversion was apparent consistently and under electron microscopy all endothelial surfaces were intact and no suture material was seen in groups I and II. In group III some suture material was covered by endothelial cells and lumen surfaces were torn; endothelization also was rough compared with groups I and II. In group IV suture material was seen in the lumen because of a loose suture knot. The endothelium also was not regular. CONCLUSIONS: The horizontal mattress suturing technique is the only technique in which the suture material never contacts the lumen. Continuous horizontal mattress suture technique is superior to the other microvascular procedures and is the safest and fastest procedure for microvascular anastomosis in rats.  相似文献   
74.
BACKGROUND: While potential benefits of robotic technology include decreased morbidity and improved recovery, some have suggested a prohibitively high cost. This study was undertaken to compare actual hospital costs of robotically assisted cardiac procedures with conventional techniques. METHODS: We conducted a retrospective review of clinical and financial data of 20 patients who underwent atrial septal defect (ASD) closure and 20 patients who underwent mitral valve repair (MVr) using either robotic techniques or a conventional approach with a sternotomy. Total hospital cost (actual resource consumption) was subdivided into operative and postoperative costs. RESULTS: Robotic technology did not significantly increase total hospital cost for ASD closure or MVr (p = 0.518 and p = 0.539). However, when including the initial capital investment for the robot through amortization of institutional costs, total hospital cost was increased by $3,773 for robotic ASD closure and $3,444 for robotic MVr (p = 0.021 and p = 0.004). The major driver of cost for robotic cases (operating room time) decreased over time. CONCLUSIONS: Robotic technology did not significantly increase hospital cost. While the absolute cost for robotic surgery was higher than conventional techniques after taking into account the institutional cost of the robot, the major driver of cost for robotic procedures will likely continue to decrease, as the surgical team becomes increasingly familiar with robotic technology. Furthermore, other benefits, such as improvement in postoperative quality of life and more expeditious return to work may make a robotic approach cost-effective. Thus, it is possible that the benefits of robotic surgery may justify investment in this technology.  相似文献   
75.
OBJECTIVE: Joint pain may cause patients to hold their limbs in mild flexion, abduction or adduction to minimize pain, regardless of the extent of articular pathology, and these positional changes may have substantial effects on the interpretation of radiographic joint space. We aimed to study the impacts of minor degrees of flexion, abduction or adduction of the hip, as well as the angle of the x-ray beam on the radiographic joint space width (JSW) of the hip joint. METHODS: In the first part of the study, 65 patients (44 males, 21 females, mean+/-SD age 49+/-17) without clinical evidence of hip osteoarthritis (OA) who underwent intravenous pyelography (IVP) were studied. The hips were differentially positioned during the sequential radiographs required for the IVP procedure. Baseline radiographs were taken at 15 degrees internal rotation of the hips [the standard position for anteroposterior (AP) pelvis radiography]; additional positions included the hips at 15 degrees and/or 30 degrees flexion, and 15 degrees adduction and/or 30 degrees abduction. Radiographic JSWs were measured at three sites using a dial caliper: superomedial, superolateral, and the point of narrowest JSW. In the second part, 15 patients without clinical evidence of hip OA who underwent supine abdominal radiography for non-rheumatological indications were evaluated by standard (AP) pelvis x-ray in the same setting and JSW measurements were made as described above. RESULTS: When the average of the three measurements of the JSW was taken for each hip, baseline JSW was 4.38+/-0.55 mm (mean+/-SD). Positioning of the hip significantly (P<0.01) affected the radiographic JSW, with apparent widening during adduction and 30 degrees flexion, (JSW 4.56+/-0.51 mm and 4.53+/-0.58 mm, mean+/-SD), respectively, but narrowing during abduction (4.17+/-0.59 mm, mean+/-SD). Fifteen degree flexion of the hip did not result in statistically significant change in JSW measurements. Upon comparison of the AP pelvis view with the supine abdominal view, neither the average JSW nor the point of narrowest JSW differed significantly, although the superolateral JSW was significantly greater on the AP pelvis view (P=0.02). CONCLUSIONS: Subtle positional changes in the hip, such as may occur during pain or in OA, may artifactually alter the measured radiographic JSW. Thus, longitudinal studies which employ hip JSW to assess disease progression may yield biased results due to changes in pain rather than structure unless care is taken to ensure constant positioning of the hip.  相似文献   
76.

Background

Lip augmentation and changing contour lines have become more popular ways of improving the appearance. However, validated measures of lip fullness for quantification of outcomes are needed; ethnic background and personal goals can optimise outcomes while tailoring lip enhancement treatment to each individual’s anatomy. The aim of this study is to analyse the morphological features of the lip in detail and to clarify the objective parameters in related with the subjective ones regarding the lip augmentation and lip reconstruction.

Methods

Standard photographs of the lips of 200 young Anatolian adults were calculated with linear and angular components. The features of the lower third of the face were analysed with the software program. Linear analyses (heights of the upper lip, the upper vermilion, the lower lip height, the lower vermillion and the chin height) and angular analyses (the upper lip, the lower lip, the apex and Cupid’s bow angles) were measured as reference points. The lip shape was classified into five groups: thin, very thin, medium, full and very full.

Results

The lower third of the face was divided into three segments (Sn–Sto, Sm–Me and Sto–Sm), and the largest portion of the lower face was occupied by the chin and the smallest by the lower lip height in both genders. The upper vermilion height was 8.07?±?1.8 mm in males and 7.08?±?1.5 mm in females. The lower vermilion height was 10.1?±?2.4 mm in males and 9.7?±?1.9 mm in females. The upper lip angle was calculated as 30.3?±?9.6° in males and 24.2?±?6.2°mm in females. The lower lip angle was calculated as 38.3?±?9.7° in males and 36.5?±?6.4° in females. Meanwhile, the angular measurements of Cupid’s bow (i.e., the apex and the central angle of Cupid’s bow) were smaller in men than in women. When the lip was analyzed, the medium and full types in upper and lower lips accounted for substantial fractions in men, whereas medium and thin types were predominant also in women.

Conclusions

With the help of certain software, this research has made possible to define the best cosmetical redesign solution of lip construction and augmentation with a natural appearance for the patient.Level of Evidence: Level III, diagnostic study.
  相似文献   
77.
Background:The fingertip is the most frequently injured and amputated segment of the hand. There are controversies about defining clear indications for microsurgical replantation. Many classification systems have been proposed to solve this problem. No previous study has simultaneously correlated different classification systems with replant survival rate. The aim of the study is to compare the outcomes of fingertip replantations according to Tamai and Yamano classifications.Results:Of the 34 fingertips, 26 (76.4%) survived. Ten (66.6%) of 15 digits replanted in Tamai zone 1 and 16 (84.2%) of 19 digits replanted in Tamai zone 2 survived. There were no replantation failures in Yamano type 1 injuries (100%) and only two failed in Yamano type 2 (75%). Replantation was successful in 14 of 20 Yamano type 3 injuries, but six failed (70%). The percentage of success rates was the least in the hybridized groups of Tamai zone 1-Yamano type 2 and Tamai zone 1-Yamano type 3. Although clinically distinct, the survival rates between the groups were not statistically significantly different.Conclusions:The level and mechanism of injury play a decisive role in the success of fingertip replantation. Success rate increases in proximal fingertip amputations without crush injury.  相似文献   
78.
The mechanical features of and biologic response to using distraction osteogenesis with the circular external fixator are the unique aspects of Ilizarov’s contribution that allows deformity correction and reconstruction of bone defects. We present a retrospective study of 20 patients who suffered from a variety of benign tumours for which external fixators (EF) were used to treat deformity, bone loss, and limb-length discrepancy. A total of 26 bony segments in twenty patients (10 males, 10 females; mean age 17 years; range 7–58 years) were treated with EF for residual problems from the tumour itself (primary treatment) in 8 patients and for complications related to the primary surgery (secondary treatment) in 12 patients. Histological diagnoses were Ollier’s disease (n = 4), Fibrous Dysplasia (n = 5), Congenital multiple exostosis (n = 5), giant cell tumour (n = 2) and one case for chondromyxoid fibroma, desmoid fibroma, chondroma and unicameral bone cyst. Various types of external fixators used to treat these problems. These were Ilizarov, unilateral fixator, multiaxial correction frame (Biomet, Parsippany, NJ), Taylor spatial frame (Memphis, TN) and smart correction multiaxial frame. The mean follow-up time was 69.5 months (range 35–108 months). The mean external fixation time was 159.5 days (range 27–300 days). The mean external fixation index was 67.4 days/cm (12–610) in 26 limbs who underwent distraction osteogenesis. The mean length of distraction was 4.9 cm (range 0.2–14 cm). At final follow-up, all patients had returned to normal activities. Complications were in the form of knee arthrodesis in one patient, pin tract infection in six and residual shortening in eight patients. The use of EF and the principles of distraction osteogenesis, in the management of problems associated with benign bone tumours and related surgery yields successful results especially in young patients. With this approach, the risk for recurrence of shortening and deformity may be minimized with overcorrection or over-lengthening as dictated by preoperative planning.  相似文献   
79.

Background

Cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with significantly longer survival in patients with peritoneal carcinomatosis (PC). So far, no morphological imaging method has proven to accurately assess the intra-abdominal tumor spread. This study was designed to predict tumor load in patients with PC using dual-modality 18FDG-PET/CT and to compare the results with those of PET and CT alone by correlating imaging findings with intraoperative staging.

Methods

Twenty-two patients with PC from gastrointestinal (n = 13), ovarian cancer (n = 8), and mesothelioma (n = 1) underwent contrast-enhanced 18FDG-PET/CT before surgery and HIPEC. In a retrospective analysis PET, CT, and fused PET/CT were separately and blindly reviewed for the extent of peritoneal involvement using the Peritoneal Cancer Index (PCI). Imaging results were correlated with the intraoperative PCI using Pearson’s correlation coefficient and linear regression analysis.

Results

There was a strong correlation between the PCI obtained with PET/CT and the surgical PCI with respect to the total score (r = 0.951) as well as in the regional analysis (small bowel, r = 0.838; other, r = 0.703). The correlation was slightly lower for CT alone (total score, r = 0.919; small bowel, r = 0.754; other, r = 0.666) and significantly lower (p = 0.002) for PET alone (total score, r = 0.793; small bowel, r = 0.553, other, 0.507).

Conclusions

Contrast-enhanced CT is superior compared with PET alone to predict the extent of PC. In our patient group, the combination of both modalities (contrast enhanced PET/CT) yielded the best results and proved to be a useful tool for selecting candidates for peritonectomy and HIPEC.  相似文献   
80.
This study was designed to determine the effect of molsidomine (MO), a precursor of nitric oxide (NO) donor, on hypoxia inducible factor alpha (HIF-1α) and Sonic hedgehog (Shh) levels considered to be involved in the development of testes ischemia/reperfusion (I-R) injury. Torsions were created by rotating ipsilateral testes 720° in a clockwise direction for 6 h and 1-h detorsion of the testis was performed. A sham operation was performed in group 1 (control, n = 7). In group 2 (I-R/Untreated, n = 7), following 6 h of unilateral testicular torsion, 1-h detorsion of the testis was performed. No drug was given. In group 3 (I-R/MO), after performing the same surgical procedure as in group 2, a NO donor MO was given at the starting time of reperfusion. In group 4 (I-R/L-NAME), after performing the same surgical procedure as in group 2, L-NAME was given at the starting time of reperfusion. Testes malondialdehyde (MDA) levels were determined as well as examining the testes histologically. Treatment of rats with MO produced a significant reduction in the levels of MDA and histopathological score compared to testes I-R groups. The Sonic hedgehog (Shh) expression in the basement membrane of the tubuli seminiferi, and sertoli and germinal cells in testicular tissue, were greatly increased in the I-R/MO group compared to groups 1, 2 and 4. Additionally, the HIF-1α expression in the interstitial spaces in testicular tissue were greatly increased in the I-R/MO group. The results suggest that MO has a protective effect against ischemia/reperfusion injury in rat testes and may affect Shh and HIF-1α signaling pathway.  相似文献   
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