This study was designed to investigate whether sectioning of the transverse carpal ligament (TCL) modifies the biomechanical behavior of the finger flexion in respect to dynamic changes of the wrist. Changes of work, load, and excursion of the flexor tendons were measured using fresh frozen cadaver hands with the wrist in 30° flexion, neutral, and 30° extension before and after division of the TCL. Change in work efficiency between intact and cut TCL groups was noted most with the wrist in flexed position (12.5%) compared to 3% in neutral wrist position and no change in wrist extension. The extended wrist group as a whole had greatest increase in the efficiency of work and load with greater than 16.2% and 14.8% changes, respectively. The significant decrease in the excursion efficiency of the flexor tendons was demonstrated when the wrist was in the flexed position. This effect was accentuated when the TCL was divided causing the bow-stringing phenomenon. The increase in the excursion of the flexor tendons could clinically result in decreased grip strength when the wrist is flexed. Furthermore, the effects of TCL division were least significant when wrist position was in extension. One could conclude from this that post-operative management after carpal tunnel release procedures should include placing the wrist in moderate extension.
Cadaver ; Fingers ; Hand ; Hand Strength ; Ligaments ; Tendons ; Wrist

The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician.
Alveolar Ridge Augmentation ; Bone Substitutes ; Dental Implants ; Humans ; Mandible* ; Maxilla* ; Sinus Floor Augmentation ; Survival Rate

Purpose: To compare the long-term changes in surgically induced astigmatism (SIA) in patients who underwent 23-gauge sutureless vitrectomy and cataract surgery together with patients who underwent cataract surgery only. Methods: We retrospectively reviewed SIA changes for 1 year after surgery in patients who received only cataract surgery using phacoemulsification (group 1) and patients who underwent 23-gauge sutureless vitrectomy and cataract surgery together (group 2). Flat keratometry (K1), steep keratometry (K2), and astigmatism axis were measured with automatic keratometry before and after the surgery. Vector analysis was used to calculate SIA at 1, 3, 6, and 12 months postoperatively. We then examined whether the SIA values at each time point were different between the two groups. Results: A total of 86 eyes were included in this study (group 1, n = 45; group 2, n = 41). The mean SIA values calculated at 1, 3, 6, and 12 months after surgery in group 1 were 0.83 ± 0.37, 0.69 ± 0.39, 0.60 ± 0.33, and 0.59 ± 0.33, respectively. In group 2, the values were 0.82 ± 0.47, 0.69 ± 0.38, 0.62 ± 0.28, and 0.61 ± 0.30, respectively. Over time, SIA decreased in both groups (all p < 0.001). There was no significant difference in the mean SIA between the two groups at each follow-up time point after surgery (p = 0.296, p = 0.728, p = 0.361, and p = 0.356, respectively). Conclusions When 23-gauge sutureless vitrectomy and cataract surgery were performed together, the astigmatism change caused by surgery did not show a significant difference compared with that of the group who received cataract surgery only. Thus, 23-gauge sutureless vitrectomy may not significantly affect corneal astigmatism.

Purpose: To compare the long-term changes in surgically induced astigmatism (SIA) in patients who underwent 23-gauge sutureless vitrectomy and cataract surgery together with patients who underwent cataract surgery only. Methods: We retrospectively reviewed SIA changes for 1 year after surgery in patients who received only cataract surgery using phacoemulsification (group 1) and patients who underwent 23-gauge sutureless vitrectomy and cataract surgery together (group 2). Flat keratometry (K1), steep keratometry (K2), and astigmatism axis were measured with automatic keratometry before and after the surgery. Vector analysis was used to calculate SIA at 1, 3, 6, and 12 months postoperatively. We then examined whether the SIA values at each time point were different between the two groups. Results: A total of 86 eyes were included in this study (group 1, n = 45; group 2, n = 41). The mean SIA values calculated at 1, 3, 6, and 12 months after surgery in group 1 were 0.83 ± 0.37, 0.69 ± 0.39, 0.60 ± 0.33, and 0.59 ± 0.33, respectively. In group 2, the values were 0.82 ± 0.47, 0.69 ± 0.38, 0.62 ± 0.28, and 0.61 ± 0.30, respectively. Over time, SIA decreased in both groups (all p < 0.001). There was no significant difference in the mean SIA between the two groups at each follow-up time point after surgery (p = 0.296, p = 0.728, p = 0.361, and p = 0.356, respectively). Conclusions When 23-gauge sutureless vitrectomy and cataract surgery were performed together, the astigmatism change caused by surgery did not show a significant difference compared with that of the group who received cataract surgery only. Thus, 23-gauge sutureless vitrectomy may not significantly affect corneal astigmatism.

Purpose: This study systematically evaluated the implications of advanced age on postsurgical outcomes following gastrectomy for gastric cancer using a national database. Materials and Methods: The 2011–2017 National Inpatient Sample was used to isolate patients who underwent gastrectomy for gastric cancer. From this, the population was stratified into those belonging to the younger age cohort (18–59 years), sexagenarians, septuagenarians, and octogenarians. The younger cohort and each advanced age category were compared in terms of the following endpoints: mortality following surgery, length of hospital stay, charges, and surgical complications. Results: This study included a total of 5,213 patients: 1,366 sexagenarians, 1,490 septuagenarians, 743 octogenarians, and 1,614 under 60 years of age. Between the younger cohort and sexagenarians, there was no difference in mortality (2.27 vs. 1.67%; P=0.30; odds ratio [OR], 1.36; 95% confidence interval [CI], 0.81–2.30), length of stay (11.0 vs. 11.1 days; P=0.86), or charges ($123,557 vs. $124,425; P=0.79). Compared to the younger cohort, septuagenarians had higher rates of in-hospital mortality (4.30% vs. 1.67%; P<0.01; OR, 2.64; 95% CI, 1.67–4.16), length of stay (12.1 vs. 11.1 days; P<0.01), and charges ($139,200 vs. $124,425; P<0.01). In the multivariate analysis, septuagenarians had higher mortality (P=0.01; adjusted odds ratio [aOR], 2.01; 95% CI, 1.18–3.43). Similarly, compared to the younger cohort, octogenarians had a higher rate of mortality (7.67% vs. 1.67%; P<0.001; OR, 4.88; 95% CI, 3.06–7.79), length of stay (12.3 vs. 11.1 days; P<0.01), and charges ($131,330 vs. $124,425; P<0.01). In the multivariate analysis, octogenarians had higher mortality (P<0.001; aOR, 4.03; 95% CI, 2.28–7.11). Conclusions Advanced age (>70 years) is an independent risk factor for postoperative death in patients with gastric cancer undergoing gastrectomy.

OBJECTIVE: The goal of this study was to evaluate the biomechanical features of human cadaveric spines implanted with the Activ L prosthesis. METHODS: Five cadaveric human lumbosacral spines (L2-S2) were tested for different motion modes, i.e. extension and flexion, right and left lateral bending and rotation. Baseline measurements of the range of motion (ROM), disc pressure (DP), and facet strain (FS) were performed in six modes of motion by applying loads up to 8 Nm, with a loading rate of 0.3 Nm/second. A constant 400 N axial follower preload was applied throughout the loading. After the Activ L was implanted at the L4-L5 disc space, measurements were repeated in the same manner. RESULTS: The Activ L arthroplasty showed statistically significant decrease of ROM during rotation, increase of ROM during flexion and lateral bending at the operative segment and increase of ROM at the inferior segment during flexion. The DP of the superior disc of the operative site was comparable to those of intact spine and the DP of the inferior disc decreased in all motion modes, but these were not statistically significant. For FS, statistically significant decrease was detected at the operative facet during flexion and at the inferior facet during rotation. CONCLUSION: In vitro physiologic preload setting, the Activ L arthroplasty showed less restoration of ROM at the operative and adjacent levels as compared with intact spine. However, results of this study revealed that there are several possible theoretical useful results to reduce the incidence of adjacent segment disease.
Arthroplasty ; Biomechanics ; Cadaver ; Humans ; Incidence ; Prostheses and Implants ; Range of Motion, Articular ; Spine ; Sprains and Strains

Although heparin is better known as an anticoagulant, it also has several anti-inflammatory effects. Heparin is known to inhibit neutrophil adhesion, chemotaxis and oxygen free radical production. In addition, heparin is also known to act as an oxygen radical scavenger. Our hypothesis was that heparin would attenuate renal ischemia reperfusion injury. In this study, we investigated whether heparin had a protective effect on renal ischemia reperfusion injury. Sheep (n = 12) were prepared for the chronic study with venous, arterial and urinary catheters inserted. In addition, pneumatic occluders and ultrasonic flow probes were placed on renal arteries. After a 5-day recovery period, the sheep were randomized to either a heparin treatment group (400 IU/kg i.v. bolus 10 minutes before renal artery occlusion, followed by a continuous effusion 25,000 IU in 250 ml of 0.9% NaCl at 10 ml/hr, n = 6) or a control group (n = 6), which received an equivalent volume of 0.9% NaCl. All the sheep then underwent 90 minutes of bilateral renal ischemia followed by 24 hours of reperfusion. Blood urea nitrogen (BUN), serum creatinine (Scr), and creatinine clearance (CrCl) were determined at various intervals during both the ischemic and reperfusion periods. Kidney tissue samples were obtained at autopsy for histologic examination. As a result, there were significant differences in the degree of inflammation (1.50 +/- 1.24 Vs 0.50 +/- 0.79, P < 0.05) between the control and heparin treatment groups, but not in the degree of injury (2.83 +/- 0.44 Vs 2.33 +/- 0.28). In this study, heparin significantly attenuated polymorphonuclear leukocytes (PMNs) infiltration within the interstitium, but it did not affect the degree of renal damage as measured by urinary chemistries or renal tubular damage as assessed by histopathologic evaluation.
Animal ; Anticoagulants/pharmacology* ; Cell Movement/drug effects ; Female ; Heparin/pharmacology* ; Ischemia/pathology* ; Kidney/pathology ; Kidney/drug effects* ; Neutrophils/physiology ; Neutrophils/drug effects* ; Renal Circulation* ; Reperfusion Injury/pathology* ; Sheep

Purpose: The purpose of this study was to examine the local tissue reactions associated with 3 different poly(lactic-co-glycolic acid) (PLGA) prototype membranes and to compare them to the reactions associated with commercially available resorbable membranes in rats. Methods: Seven different membranes—3 synthetic PLGA prototypes (T1, T2, and T3) and 4 commercially available membranes (a PLGA membrane, a poly[lactic acid] membrane, a native collagen membrane, and a cross-linked collagen membrane)—were randomly inserted into 6 unconnected subcutaneous pouches in the backs of 42 rats. The animals were sacrificed at 4, 13, and 26 weeks. Descriptive histologic and histomorphometric assessments were performed to evaluate membrane degradation, visibility, tissue integration, tissue ingrowth, neovascularization, encapsulation, and inflammation. Means and standard deviations were calculated. Results: The histological analysis revealed complete integration and tissue ingrowth of PLGA prototype T1 at 26 weeks. In contrast, the T2 and T3 prototypes displayed slight to moderate integration and tissue ingrowth regardless of time point. The degradation patterns of the 3 synthetic prototypes were similar at 4 and 13 weeks, but differed at 26 weeks. T1 showed marked degradation at 26 weeks, whereas T2 and T3 displayed moderate degradation.Inflammatory cells were present in all 3 prototype membranes at all time points, and these membranes did not meaningfully differ from commercially available membranes with regard to the extent of inflammatory cell infiltration. Conclusions The 3 PLGA prototypes, particularly T1, induced favorable tissue integration, exhibited a similar degradation rate to native collagen membranes, and elicited a similar inflammatory response to commercially available non–cross-linked resorbable membranes.The intensity of inflammation associated with degradable dental membranes appears to relate to their degradation kinetics, irrespective of their material composition.

Purpose: The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion. Methods: Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/ CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis.Patients were followed up after the final crown insertion and again at 1 year post-procedure. Results: Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by −2.11 mm for the DBBM-C/CM group, −1.62 mm for the DBBM-C group, and −1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by −0.27 mm for the DBBM-C/CM group, −2.73 mm for the DBBM-C group, and −1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were −0.19 mm in the DBBM-C/CM group, −0.09 mm in the DBBM-C group, and −0.29 mm in the SH group. Conclusions Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.

Purpose: The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion. Methods: Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/ CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis.Patients were followed up after the final crown insertion and again at 1 year post-procedure. Results: Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by −2.11 mm for the DBBM-C/CM group, −1.62 mm for the DBBM-C group, and −1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by −0.27 mm for the DBBM-C/CM group, −2.73 mm for the DBBM-C group, and −1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were −0.19 mm in the DBBM-C/CM group, −0.09 mm in the DBBM-C group, and −0.29 mm in the SH group. Conclusions Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.