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Clinical Biomechanics (Bristol, Avon) May 2023Complex proximal humerus fractures place high demands on osteosynthetic treatment. In some cases, double plating has already been used to increase primary stability of...
Dynamic biomechanical investigation of a novel sulcus bicipitalis plate in combination with a conventional locking plate for the treatment of complex proximal humerus fractures.
BACKGROUND
Complex proximal humerus fractures place high demands on osteosynthetic treatment. In some cases, double plating has already been used to increase primary stability of the osteosynthesis. This approach was advanced in the present study by developing an additive plate for the sulcus bicipitalis. To demonstrate the superior primary stability of the newly developed plate osteosynthesis, a biomechanical comparison against a conventional locking plate with an additional calcar screw was performed.
METHODS
Ten pairs of cadaveric humeri were treated proximally with a locking plate (PENTA plate small fragment, INTERCUS). Each had a two-part fracture model with a fracture gap of 10 mm. All right humeri were treated with an additive novel plate that extends along the bicipital sulcus and encircles the lesser tuberosity proximally. First, the specimens were loaded sinusoidally at 250 N in 20° abduction for 5000 cycles. Afterwards quasi-static loading until failure was applied.
FINDINGS
The movement at the fracture gap due to the cyclic loading occurred mainly as rotation around the z-axis, corresponding to a tilt medially and distally. The double plate osteosynthesis reduces the rotation by approximately 39%. For all load cycles observed, except 5000 cycles, medial and distal rotation of the head was significantly reduced by the double plate. The failure loads showed no significant differences between the groups.
INTERPRETATION
In the tested scenario under cyclic loading, the novel double plate osteosynthesis showed a significant superiority of primary stability over the conventional treatment with one locking plate. Furthermore, the study showed the advantages of cyclic load application over quasi-static load application until failure.
Topics: Humans; Shoulder Fractures; Fracture Fixation, Internal; Humerus; Bone Screws; Humeral Fractures; Bone Plates; Biomechanical Phenomena; Cadaver
PubMed: 37156192
DOI: 10.1016/j.clinbiomech.2023.105984 -
The Journal of Urology Oct 2003We describe a new technique for staged hypospadias repair in which the urethral plate is divided proximally at the time of the first stage.
PURPOSE
We describe a new technique for staged hypospadias repair in which the urethral plate is divided proximally at the time of the first stage.
MATERIALS AND METHODS
A total of 14 patients with proximal hypospadias associated with severe chordee were operated on using a new staged technique. At the time of the first stage the urethral plate was divided proximally at the level of the hypospadiac meatus. In 8 of 14 patients the intact plate was then incised and tubularized with the Snodgrass technique. In 6 patients the plate was tubularized at the time of the second stage. Correction of chordee was accomplished with dorsal plication and/or corporal body grafting. Byar's flaps were used to fill in the residual gap between the proximal hypospadiac meatus and the newly tubularized neourethra. The transposed flaps in the area of the urethral defect were then tubularized at the second stage.
RESULTS
Followup ranged from 6 months to 3 years. Complications included a proximal pinpoint fistula and diverticulum in 1 case. An additional patient also had formation of a mild diverticulum that has not required surgical revision. No patients have had any evidence of distal urethral stricture formation.
CONCLUSIONS
Proximal division of the urethral plate and application of the Snodgrass procedure to the staged repair of hypospadias have resulted in improved functional and cosmetic results. The major advantage of this new technique is preservation and use of the native urethral plate in the glans and subcoronal area. When complications occur with this technique, they are less severe compared to those of the traditional staged approach.
Topics: Follow-Up Studies; Humans; Hypospadias; Infant; Male; Outcome and Process Assessment, Health Care; Penile Induration; Penis; Reoperation; Retrospective Studies; Surgical Flaps; Suture Techniques; Urethra
PubMed: 14501666
DOI: 10.1097/01.ju.0000084258.93064.f4 -
Developmental Dynamics : An Official... Nov 2009During fin regeneration, osteoblasts must continually differentiate for outgrowth of the bony fin rays. Bone maturity increases in a distal-proximal manner, and...
During fin regeneration, osteoblasts must continually differentiate for outgrowth of the bony fin rays. Bone maturity increases in a distal-proximal manner, and osteoblast maturation can be detected similarly when following gene expression. We find that early markers for osteoblast differentiation are expressed in a discrete domain at the distal end of the fin, just proximal to the adjacent germinal compartment of dividing cells. Matrix genes, required at later stages developmentally, are expressed in a population of cells proximally to the early genes. A marker for mature osteoblasts is expressed in cells further proximal. These domains of gene expression are partially overlapping, perhaps revealing additional levels of osteoblast maturity. We suggest a model for growth where new cells are continually added to the distal-most osteoblast compartment, while osteoblasts in more proximal locations differentiate, thus translating developmental time to location on the proximal-distal axis.
Topics: Animals; Bone Regeneration; Cell Differentiation; Osteoblasts; Osteogenesis; Osteopontin; Sp7 Transcription Factor; Transcription Factors; Zebrafish; Zebrafish Proteins
PubMed: 19842180
DOI: 10.1002/dvdy.22114 -
Muscle & Nerve Mar 2000Median neuropathies proximal to the wrist are uncommon and usually result from penetrating injuries, fracture dislocation of the distal humerus, or compression by...
Median neuropathies proximal to the wrist are uncommon and usually result from penetrating injuries, fracture dislocation of the distal humerus, or compression by fibrous bands. A 66-year-old man suffered a comminuted fracture of the proximal humerus after a fall. Electrodiagnostic studies revealed a severe proximal median neuropathy and a mild distal radial mononeuropathy. Proximal median neuropathy rarely occurs in humeral neck fracture, mostly because the median nerve is not in close contact with the humerus proximally.
Topics: Accidental Falls; Aged; Fractures, Comminuted; Humans; Humerus; Male; Median Nerve; Neural Conduction; Radiography
PubMed: 10679720
DOI: 10.1002/(sici)1097-4598(200003)23:3<426::aid-mus15>3.0.co;2-u -
American Journal of Physiology.... Dec 2005We have previously shown that neonate rabbit tubules have a lower chloride permeability but comparable mannitol permeability compared with adult proximal tubules. The...
We have previously shown that neonate rabbit tubules have a lower chloride permeability but comparable mannitol permeability compared with adult proximal tubules. The surprising finding of lower chloride permeability in neonate proximals compared with adults impacts net chloride transport in this segment, which reabsorbs 60% of the filtered chloride in adults. However, this maturational difference in chloride permeability may not be applicable to other species. The present in vitro microperfusion study directly examined the chloride and mannitol permeability using in vitro perfused rat proximal tubules during postnatal maturation. Whereas there was no maturational change in mannitol permeability, chloride permeability was 6.3 +/- 1.3 x 10(-5) cm/s in neonate rat proximal convoluted tubule and 16.1 +/- 2.3 x 10(-5) cm/s in adult rat proximal convoluted tubule (P < 0.01). There was also a maturational increase in chloride permeability in the rat proximal straight tubule (5.1 +/- 0.6 x 10(-5) cm/s vs. 9.3 +/- 0.6 x 10(-5) cm/s, P < 0.01). There was no maturational change in bicarbonate-to-chloride permeabilities (P(HCO3)/P(Cl)) in the rat proximal straight tubules (PST) and proximal convoluted tubules (PCT) or in the sodium-to-chloride permeability (P(Na)/P(Cl)) in the proximal straight tubule; however, there was a significant maturational decrease in proximal convoluted tubule P(Na)/P(Cl) with postnatal development (1.31 +/- 0.12 in neonates vs. 0.75 +/- 0.06 in adults, P < 0.001). There was no difference in the transepithelial resistance measured by current injection and cable analysis in the PCT, but there was a maturational decrease in the PST (7.2 +/- 0.8 vs. 4.6 +/- 0.1 ohms x cm2, P < 0.05). These studies demonstrate there are maturational changes in the rat paracellular pathway that impact net NaCl transport during development.
Topics: Aging; Animals; Animals, Newborn; Cell Membrane Permeability; Chlorine; Kidney Tubules, Proximal; Permeability; Rats; Rats, Sprague-Dawley
PubMed: 16051720
DOI: 10.1152/ajpregu.00257.2005 -
BMC Gastroenterology Nov 2010In the last years a trend towards proximalization of colorectal carcinomas (CRC) has been reported. This study aims to evaluate the distribution of CRC and adenomatous...
BACKGROUND
In the last years a trend towards proximalization of colorectal carcinomas (CRC) has been reported. This study aims to evaluate the distribution of CRC and adenomatous polyps (ADP) to establish the presence of proximalization and to assess the potential predictors.
METHODS
We retrieved histology reports of colonic specimens excised during colonoscopy, considering the exams performed between 1997 and 2006 at Cuneo Hospital, Italy. We compared the proportion of proximal lesions in the period 1997-2001 and in the period 2002-2006.
RESULTS
Neoplastic lesions were detected in 3087 people. Proximal CRC moved from 25.9% (1997-2001) to 30.0% (2002-2006). Adjusting for sex and age, the difference was not significant (OR 1.23; 95% CI: 0,95-1,58). The proximal ADP proportion increased from 19.2% (1997-2001) to 26.0% (2002-2006) (OR: 1.43; 95% CI: 1.17-1.89). The corresponding figures for advanced proximal ADP were 6.6% and 9.5% (OR: 1.48; 95% CI: 1.02-2.17). Adjusting for gender, age, diagnostic period, symptoms and number of polyps the prevalence of proximal advanced ADP was increased among people ≥ 70 years compared to those aged 55-69 years (OR 1.49; 95% CI: 1.032.16). The main predictor of proximal advanced neoplasia was the number of polyps detected per exam (> 1 polyp versus 1 polyp: considering all ADP: OR 2.16; 95% CI: 1.59-2.93; considering advanced ADP OR 1.63; 95% CI: 1.08-2.46). Adjusting for these factors, the difference between the two periods was no longer significant.
CONCLUSIONS
CRC do not proximalize while a trend towards a proximal shift in adenomas was observed among people ≥ 70 years.
Topics: Adenomatous Polyps; Aged; Colon; Colonic Neoplasms; Female; Humans; Incidence; Italy; Male; Middle Aged; Multivariate Analysis; Prevalence; Retrospective Studies
PubMed: 21108823
DOI: 10.1186/1471-230X-10-139 -
Annals of Surgery Jun 1997The purpose of this study is to compare the outcome of patients with proximal gastric cancer (PGC) treated by a transabdominal-only resection to that of patients with... (Comparative Study)
Comparative Study
OBJECTIVE
The purpose of this study is to compare the outcome of patients with proximal gastric cancer (PGC) treated by a transabdominal-only resection to that of patients with distal gastric cancer (DGC).
SUMMARY BACKGROUND DATA
It has been suggested that PGC is inherently more aggressive than DGC. The worse survival of PGC compared with that of DGC may be in part, because of the difficulty distinguishing PGC from distal esophageal adenocarcinoma. By defining a subset of PGC resected using an transabdominal-only approach, one may discriminate true PGC from distal esophageal adenocarcinoma. This subset of patients is a more appropriate comparison group when analyzing outcome relative to patients with DGC.
METHODS
A review of the prospective database for gastric adenocarcinoma at Memorial Sloan-Kettering Cancer Center between July 1985 and August 1995 identified 98 patients with PGC resection via a transabdominal-only approach. Of these, 65 underwent proximal gastrectomy and 33 underwent total gastrectomy. For DGC, 258 required a distal gastrectomy and 71 required total gastrectomy.
RESULTS
The overall 5-year survival of patients with PGC was 42% (median survival, 47 months), whereas the 5-year survival for patients with DGC was 61% (median survival, 106 months, p = 0.03). Within each stage, there were no significant survival differences, but in all stages, survival was better for patients with DGC. More important, the site of the primary tumor appears to affect survival, with a worse outcome as the tumor moves proximally.
CONCLUSIONS
Despite excluding distal esophageal cancers, survival for patients with PGC remains worse than for those with DGC. Late stage of presentation could not explain this difference. It appears that PGCs are inherently more aggressive than are DGCs. In addition, site of the primary tumor appears to affect outcome, with a trend toward a worse outcome as the tumor moves proximally.
Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Female; Gastrectomy; Humans; Male; Middle Aged; Neoplasm Staging; Stomach Neoplasms; Survival Analysis; Treatment Outcome
PubMed: 9230808
DOI: 10.1097/00000658-199706000-00005 -
Journal of Hand Surgery (Edinburgh,... Jun 2001Access to the proximal interphalangeal joint of the finger for arthroplasty is difficult without detaching its stabilizers or dividing the tendons that cross it, which...
Access to the proximal interphalangeal joint of the finger for arthroplasty is difficult without detaching its stabilizers or dividing the tendons that cross it, which then require repair and slow rehabilitation. We describe a method that conserves both, so facilitating post-operative rehabilitation.A C-shaped incision is made on the dorsum of the finger. The lateral bands of the extensor expansion are separated from the central slip proximally to the extensor hood. They are then retracted to expose the condyles of the proximal phalanx, which are excised. The PIP joint is then dislocated between the central slip and a lateral band allowing the remainder of the head to be excised. The middle and proximal phalanges are then prepared to accept the prosthesis. The prosthesis is then inserted and the joint is reduced. The lateral bands of the extensor mechanism are sutured back to the central slip before the skin is closed.
Topics: Arthroplasty, Replacement; Collateral Ligaments; Finger Joint; Humans; Joint Prosthesis
PubMed: 11386774
DOI: 10.1054/jhsb.2000.0541 -
Diseases of the Esophagus : Official... 2012An unbuffered layer of acidity that escapes neutralization by food has been demonstrated in volunteers and gastroesophageal reflux disease patients. This postprandial...
An unbuffered layer of acidity that escapes neutralization by food has been demonstrated in volunteers and gastroesophageal reflux disease patients. This postprandial proximal gastric acid pocket (PPGAP) is manometrically defined by the presence of acid reading (pH<4) in a segment of the proximal stomach between nonacid segments distally (food) and proximally (lower esophageal sphincter or distal esophagus). The PPGAP may have important clinical implications; however, it is still poorly understood. Gastric anatomy and physiology seem to be important elements for PPGAP genesis. Gastric operations and acid suppression medications may decrease distal - proximal intragastric acid reflux and help control gastroesophageal reflux.
Topics: Esophageal pH Monitoring; Gastric Acid; Gastric Acidity Determination; Gastroesophageal Reflux; Gastrointestinal Motility; Humans; Postprandial Period; Stomach
PubMed: 22171648
DOI: 10.1111/j.1442-2050.2011.01293.x -
Knee Surgery, Sports Traumatology,... Dec 2011This paper presents a case report of persistent low back pain and suspected lumbar radiculopathy. A synostosis at the level of the proximal tibiofibular joint was...
This paper presents a case report of persistent low back pain and suspected lumbar radiculopathy. A synostosis at the level of the proximal tibiofibular joint was diagnosed. After successful resection of the synostosis, the low back symptoms resolved completely. This is the first report of a proximal tibiofibular synostosis as a possible cause of referred pain proximally.
Topics: Diagnosis, Differential; Fibula; Humans; Low Back Pain; Lumbar Vertebrae; Male; Middle Aged; Radiculopathy; Synostosis; Tibia
PubMed: 21222100
DOI: 10.1007/s00167-010-1379-7