A hydrocellular foam dressing versus gauze: effects on the healing of rat excisional wounds.

OBJECTIVE: Hydrocellular foam dressings are characterised by their ability to create a moist wound healing environment and absorb high amounts of exudate. In this study, we examined the effect of a hydrocellular foam dressing on the healing of rat excisional wounds. METHOD: One full-thickness wound was made on the back of rats and wounds were treated with hydrocellular foam dressing or gauze dressing. To examine the histology of the wound, haematoxylin and eosin (HE) staining was performed. Gene expression of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), hepatocyte growth factor (HGF) and hypoxia inducible factor-1 alpha (HIF-1a) in granulation tissue was examined by real-time reverse transcription polymerase chain reaction (real-time RT-PCR). VEGF protein was measured by ELISA. RESULTS: The hydrocellular foam dressing promoted formation of granulation tissue and significantly promoted wound closure. A scab formed on the surface of granulation tissue in the gauze-treated wounds, which disturbed epithelialisation. In addition, the expression of VEGF and mRNA was higher in the gauze-treated wounds. CONCLUSION: These results supports the hypothesis that gauze encourages scab formation, which impairs epithelialisation and increases VEGF expression. In contrast, hydrocellular foam dressing accelerates epithelialisation and new vessel formation in granulation tissue.

Tumorous calcification causing carpal tunnel syndrome.

PURPOSE: There is little information on solitary tumorous calcification causing carpal tunnel syndrome in the literature. This study describes our experience with surgically treated cases of solitary tumorous calcification causing carpal tunnel syndrome. METHODS: Seven patients with symptomatic carpal tunnel syndrome who had tumorous calcification in the carpal tunnel confirmed by radiographical examinations and had then undergone open incisional carpal tunnel release were reviewed. The precise location and the appearance of the calcified mass were confirmed with the preoperative radiographic examinations and the operative records. The additional histology and the composition analysis of the calcified mass were also reviewed in five removed calcifications. RESULTS: Radiographs of each hand revealed a mass of calcification lying anterior to the capitate bone in the carpal tunnel. Intraoperatively, an oval calcified nodule, measuring 10 x 10 x 10 - 18 mm, was observed overlying the capitate, attached firmly to the palmar radiocarpal extrinsic ligament. A composition with an average of 60 % basic calcium phosphate was revealed by infrared absorption spectrometry. Histological sections showed a calcified deposit surrounded by fibrocartilagenous tissue in three cases. CONCLUSION: These facts suggest that the pathogenesis of tumorous calcification causing carpal tunnel syndrome is comparable with that of calcifying tendinitis of the rotator cuff in which a cell-mediated reactive process plays an important role at the tendon insertion.

A three-dimensional quantitative analysis of carpal deformity in rheumatoid wrists.

We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid patients in which the carpal bones were shifted ulnarwards on plain radiography. Three-dimensional bone models of the carpus and radius were created by computerised tomography with the wrist in the neutral position. The location of the centroids and rotational angle of each carpal bone relative to the radius were calculated and compared with those of ten normal wrists. In the radiocarpal joint, the proximal row was flexed and the centroids of all carpal bones translocated in an ulnar, proximal and volar direction with loss of congruity. In the midcarpal joint, the distal row was extended and congruity generally well preserved. These findings may facilitate more positive use of radiocarpal fusion alone for the deformed rheumatoid wrist.

The Function of the Distal Interosseous Membrane and its Relevance to the Stability of the Distal Radioulnar Joint: An Anatomical and Biomechanical Review.

The purpose of this article is to review functional anatomy and biomechanics of the distal interosseous membrane (DIOM) and its relevance to the stability of the distal radioulnar joint. The intact DIOM constrained dorsal dislocation of the radius, but it seldom constrained palmar dislocation. A residual ulnar translation deformity of the radial shaft in distal radius fractures has the potential to cause the distal radioulnar joint instability when the triangular fibrocartilage complex injury is also present, because it may result in detensioning of DIOM. Ulnar shortening with the osteotomy performed proximal to the attachment of the DIOM had a more favorable effect on stability of the DRUJ compared with the effect of distal osteotomy, especially in the presence of the distal oblique bundle (DOB). The longitudinal resistance to ulnar shortening was significantly greater in proximal shortening than in distal shortening.

Impaired response of gastric vessels to prostaglandin E2 in rats with persistent obstructive jaundice.

We investigated the response of gastric vessels to prostaglandin (PG) E2 after intra-duodenal release of bile in rats with obstructive jaundice. The animals were divided in four groups according to duration of bile duct obstruction (BDO): control and 1 week (W), 2W, and 3W groups. Prolonged BDO decreased gastric mucosal blood flow (BF) significantly. The BF recovered after the release of BDO in the 1W and 2W groups, but not in the 3W group. BDO decreased PGE2 content in gastric mucosa in the 1W, 2W, and 3W groups. PGE2 decreased vascular perfusion pressure of the isolated stomach in the control and 2W groups, but not in the 3W group. The response of gastric vessels to PGE2 was poor in the 3W group compared with the control and 2W groups. Decreased PGE2 in the gastric mucosa and decreased response of gastric vessels to PGE2 may affect gastric blood flow in obstructive jaundice.

Reconstruction of the coronoid for chronic dislocation of the elbow. Use of a graft from the olecranon in two cases.

Persistent dislocation of the elbow after a fracture of the coronoid process is a difficult problem. We have performed an open reduction with reconstruction of the coronoid by an osteocartilaginous graft from the ipsilateral olecranon for two patients. Both achieved a painless, stable joint with a functional range of movement. The joint surface of the graft has a similar curve to that of the coronoid giving good congruency and stability. The technique is simple and the graft is obtained through the same incision.

The relationship between the site of nonunion of the scaphoid and scaphoid nonunion advanced collapse (SNAC).

We studied retrospectively the radiographs of 33 patients with late symptoms after scaphoid nonunion in an attempt to relate the incidence of scaphoid nonunion advanced collapse (SNAC) to the level of the original fracture. We found differing patterns for nonunion at the proximal, middle and distal thirds. The mean intervals between fracture and complaint were 20.9, 6.7 and 12.6 years and obvious degenerative changes occurred in 85.7%, 40.0% and 33.3%, for the six proximal-, eight middle- and two distal-third nonunions, respectively. Nonunion at the proximal and middle thirds showed the first degenerative changes at the radioscaphoid joint, and this was followed by narrowing of the scaphocapitate and then the lunocapitate joints. In our two nonunions of the distal third degenerative changes were seen only at the lunocapitate joint. Most patients with SNAC and nonunion of the middle or distal third showed dorsal intercalated instability; few patients with nonunion of the proximal third developed this deformity. We discuss the initial management of nonunion of the scaphoid at different levels in the light of our findings, and make recommendations.

Attritional rupture of flexor tendons by the head of the ulna associated with a chronic longitudinal radioulnar dissociation.

A 62-year-old woman sustained multiple attritional ruptures of the flexor tendons at the wrist caused by displacement of the head of the ulna. She had had injuries of the wrist and elbow when she was young, which were thought to have caused chronic longitudinal radioulnar dissociation with palmar dislocation of the head of the ulna. Attrition of the flexor tendons by the dislocated ulnar head during pronation and supination was the major mechanism for the ruptures in this case. She was successfully treated with tendon transfer and resection of the ulnar head.

Inhibitory effect of peptide YY on gastric acid output in rats.

The administration of peptide YY (PYY: 0.8, 1.6 and 3.2 nmol/kg/h, i.v.) to fasting rats inhibited not only baclofen (2 mg/kg, s.c.)-stimulated gastric acid output and gastric mucosal blood flow, but also pentagastrin (8 micrograms/kg/h, i.v.)-stimulated gastric acid output. PYY (3.2 nmol/kg/h) reduced baclofen-induced acid output more than pentagastrin-induced acid output, i.e., by 61.8 +/- 11.5% compared to 35.3 +/- 8.2%. PYY inhibited acetylcholine (ACh) release from cholinergic nerve endings of gastric body evoked by electrical transmural stimulation (ETS: 1 msec, 10 V, 3 Hz, 30 sec) by 47.2 +/- 3.5%. The mechanism of the inhibitory effect of PYY on gastric acid output seems to involve decreased gastric mucosal blood flow and reduced ACh release from cholinergic nerves.

[Effects of dopamine on stress ulcer].

Preventive effect of dopamine on stress ulcer formation was investigated in rats. Dopamine 1-10 micrograms/kg/min suppressed the elevation of ulcer index significantly after water immersion and restraint stress in a dose-dependent fashion, however ulcer indices of 25 micrograms/kg/min of dopamine were higher than 10 micrograms/kg/min. Dopamine 1-10 micrograms/kg/min suppressed the decrease of gastric mucosal blood flow, gastric mucosal prostaglandin E2 content and gastric transmucosal potential difference during stress loading in a dose-dependent manner, although the suppression of them in 25 micrograms/kg/min of dopamine was smaller than in 10 micrograms/kg/min also. Dopamine suppressed the increase of gastric acid secretion and gastric motility during stress loading in a dose-dependent fashion up to 25 micrograms/kg/min. These results indicates that dopamine suppresses the formation of stress ulcer by increasing defensive factors and decreasing aggressive factors.

[The mechanism of development of acute gastric ulceration following biliary drainage in obstructive jaundice].

Upper gastrointestinal hemorrhage occurs occasionally in the time of surgery or biliary infection in patients with obstructive jaundice. In the present study, the influence of obstructive jaundice and biliary drainage on the rat gastric mucosa was examined. Serum t-Bil, GOT and Alp increased during obstructive jaundice, but decreased following biliary drainage. Hexose and fucose levels in gastric mucosa decreased during obstructive jaundice; both of them increased in the 1- and 2-week jaundiced groups, however, neither increased in the 3-week jaundiced group following biliary drainage. Prolonged obstructive jaundice demonstrated a marked increase of ulcer index (UI) and decrease of gastric mucosal blood flow (BF) following water immersion and restraint stress. Biliary drainage induced these changes in the 1- and 2-week jaundiced groups, but induced neither of these changes towards recovery in the 3-week jaundice group. Prostaglandin (PG) E2 induced significant decrease in isolated gastric vascular perfusion pressure in the 2-week jaundiced group; it did not, however, have this effect in the 3-week jaundiced group. In conclusion, it was speculated that differences between the 3-week and 2-week jaundiced groups were present in sensitivity to PGE2 in the gastric vascular system, and that different reactions of the gastric microcirculation resulted in different changes in the gastric mucosal state following biliary drainage.

[A study of bleeding peptic ulcer in the elderly in the view of risk factors].

We treated 448 patients for peptic ulcer from 1970 to 1988. Among them, 52 cases were bleeding peptic ulcer in the elderly. 32 cases (61.6%) had a duration of illness of less than 3 months, and the most common symptom was abdominal pain (51.9%). 22 cases (44.0%) were in shock and 32 cases (62.7%) had accessory diseases. Twelve cases were treated medically, while 40 cases were treated surgically. Elective operations were performed in 15 cases, and their mortality was 6.7%. Emergent operations were performed in 25 cases, and their mortality was 28.0%. The mortality of of cases involving both shock and accessory diseases was 57.1%, and of this group, all 3 cases treated medically died. When bleeding exceeded 2000cc was the mortality 46.7%. Regarding cases of emergent operation involving shock or accessory diseases, the mortality was 18.2% in the cases treated medically for less than 4 days and had the episodes of massive bleeding less than 3 times, but 62.5% in other cases. The results of this study suggest that aggressive surgical treatment in an early stage may reduce the mortality in elderly patients with peptic ulcer.

[A case of obstructive jaundice caused by incarceration of pancreatic stones in the ampulla of papilla Vater].

A very rare case of obstructive jaundice caused by the incarceration of pancreatic stones in the ampulla of papilla Vater is reported. A forty-eight-year-old man, who had been taking alcohol daily for 10 years, was admitted to our hospital because of recurrent attacks of upper abdominal pain. Biochemical analysis demonstrated typical pattern of chronic pancreatitis. US, CT and ERCP showed a markedly dilated pancreatic duct and pancreatic calcifications. Cholecystolithiasis, or dilatation of the choledochus was not noted. Conservative treatment was performed under the diagnosis of chronic calcifying pancreatitis for one month. Then, obstructive jaundice, severe epigastralgia, and high fever occurred. Obstructive jaundice with sudden onset and existence of pancreatic stones suggested incarceration of pancreatic stones in the bile duct, and cephalic pancreaticoduodenectomy was performed. The largest pancreatic stone was incarcerated into the ampulla of papilla Vater. Histopathological analysis of the pancreas showed severe chronic pancreatitis. No report of the similar case can be found in the literature. Incarceration of pancreatic stones into biliary system might be very rare, however, should not be forgotten in differential diagnoses of obstructive jaundice in chronic pancreatitis patients.

A comparison of 3-D computed tomography versus 2-D radiography measurements of ulnar variance and ulnolunate distance during forearm rotation.

Positive ulnar variance is associated with ulnar impaction syndrome and ulnar variance is reported to increase with pronation. However, radiographic measurement can be affected markedly by the incident angle of the X-ray beam. We performed three-dimensional (3-D) computed tomography measurements of ulnar variance and ulnolunate distance during forearm rotation and compared these with plain radiographic measurements in 15 healthy wrists. From supination to pronation, ulnar variance increased in all cases on the radiographs; mean ulnar variance increased significantly and mean ulnolunate distance decreased significantly. However on 3-D imaging, ulna variance decreased in 12 cases on moving into pronation and increased in three cases; neither the mean ulnar variance nor mean ulnolunate distance changed significantly. Our results suggest that the forearm position in which ulnar variance increased varies among individuals. This may explain why some patients with ulnar impaction syndrome complain of wrist pain exacerbated by forearm supination. It also suggests that standard radiographic assessments of ulnar variance are unreliable.

Comparison of three dimensional and radiographic measurements in the analysis of distal radius malunion.

To estimate the accuracy of radiographic deformity evaluation for distal radius malunion, we compared the results obtained from radiographic measurements (palmar tilt, radial angle, and ulnar variance) with those from the three-dimensional (3D) method using computer bone models in 20 dorsally tilted malunions. Dorsal tilt deformity, radial tilt deformity, and shortening deformity were calculated using the unaffected side as a reference. The 3D method showed a slightly lower value for dorsal tilt deformity than the radiographic evaluation, but the difference was < 10° in all cases. In patients with dorsal tilt ≥ 40°, notable differences in radial tilt evaluation were observed between the two methods compared with patients with less dorsal tilt. The 3D shortening showed positive correlations with radiographic evaluation, but a discrepancy of ≥ 2 mm was observed in eight cases. Palmar tilt is reliable for surgical planning, but radial angle and ulnar variance may be less accurate than previously thought.

Palmar reconstruction of the triangular fibrocartilage complex for instability of the distal radioulnar joint: a biomechanical study.

We developed a new triangular fibrocartilage complex reconstruction technique for distal radioulnar joint instability in which the palmar portion of the triangular fibrocartilage complex was predominantly reconstructed, and evaluated whether such reconstruction can restore stability of the distal radioulnar joint in seven fresh cadaver upper extremities. Distal radioulnar joint instability was induced by cutting all soft-tissue stabilizers around the distal ulna. Using a palmar approach, a palmaris longus tendon graft was sutured to the remnant of the palmar radioulnar and ulnocarpal ligaments. The graft was then passed through a bone tunnel created at the fovea and was sutured. Loads were applied to the radius, and dorsopalmar displacements of the radius relative to the ulna were measured using an electromagnetic tracking device in neutral rotation, 60° supination and 60° pronation. We compared the dorsopalmar displacements before sectioning, before reconstruction and after reconstruction. Dorsopalmar instability produced by sectioning significantly improved in all forearm positions after reconstruction.

Three-dimensional deformity analysis of malunited distal radius fractures and their influence on wrist and forearm motion.

Little information exists about three-dimensional (3-D) deformity patterns of malunited distal radius fractures including axial deformity. The current study aimed to clarify the 3-D deformity pattern of malunited distal radius fractures and reveal the influence of osseous deformities, including axial rotation deformity, on wrist and forearm motion. The deformity of 20 dorsally tilted malunions were evaluated using 3-D computer models created from CT data, and correlations between deformity components and range of motion were assessed. The 3-D deformity analysis showed that axial malalignment in pronation, which showed a correlation with the degree of radial tilt deformity, was very common. A radial tilt deformity of > 5° was observed in only 45% of cases. Although the range of wrist flexion and extension showed a correlation with dorsal tilt deformity, the range of forearm pronation and supination did not correlate with distal radius deformities.

Early, wide excision of heterotopic ossification in the medial elbow.

To prevent the occurrence of secondary contracture during maturation of heterotopic ossification of the elbow, early, wide excision of heterotopic ossification was performed on 9 consecutive patients with a stiff elbow caused by the mass. The average duration between initial injury and operation was 7.7 months. The thick, elastic mass on the posterior oblique ligament of the medial collateral ligament, which included mature and immature heterotopic ossification, was resected widely with the posterior oblique ligament, the posteromedial joint capsule, and the surrounding scar tissue. After an average follow-up of 52.0 months, the total arc of motion improved from a preoperative mean of 37.3 degrees to a postoperative mean of 112.8 degrees. No patient complained of instability or pain on movement. Despite recurrence of spotty heterotopic ossification at the medial elbow in 5 cases, at final follow-up, a sufficient range of motion was obtained in all patients.