A cadaveric study of the single-portal endoscopic carpal tunnel release.

Forty-three human cadavers underwent single-portal endoscopic carpal tunnel release using the Agee technique. Subsequent independent open dissection revealed complete release of all potentially compressing transverse structures in 19 specimens and incomplete release in 24 specimens. There were 2 specimens with vascular injuries; one transection of a perforating branch of the palmar arch, and one transection of the ulnar artery at the entry portal. The 43 specimens were divided into three groups: group 1 (13 specimens) were released by the senior author in 1989; group 2 (13 specimens) were released by the senior author in 1992; and group 3 (17 specimens) were released by surgeons learning the technique under direct supervision of the senior author. Complete release was 5 of 13 for group 1, 6 of 13 for group 2, and 8 of 17 for group 3. This study indicates that incomplete release is an inherent feature of this technique regardless of the surgeon's experience and despite blade redesign. The significance of incomplete release is unknown and must be determined in long-term clinical studies.

Prospective randomized comparison of polyvinyl bougies and through-the-scope balloons for dilation of peptic strictures of the esophagus.

We prospectively compared the efficacy of polyvinyl bougies (Savary type) passed over a guide wire and through-the-scope balloons for the dilation of peptic esophageal strictures in a randomized study. Thirty-four patients, 17 in each treatment arm, were studied. At entry, dysphagia was assessed according to a six-point scale (0, unable to swallow; 5, normal). The end-point for dilation was to size 45F or 15 mm. Discomfort during the procedure was graded on a four-point scale (0, no discomfort; 1, mild; 2, moderate; 3, severe discomfort). Follow-up visits were at 1 week, 1 month, 3 months, and every 3 months thereafter for 2 years. At the 1-week visit, the size of esophageal lumen was measured by 8-, 10-, and 12-mm pills. Both devices effectively relieved dysphagia. By life-table analysis, stricture recurrence during the first year of follow-up was similar in both groups, but during the second year, the risk of recurrence was significantly lower in patients whose strictures were dilated with balloons. Other advantages of balloons included the need for fewer treatment sessions to achieve the defined end-diameter for dilation (1.1 + 0.1 versus 1.7 + 0.2, p < .05), and less procedural discomfort (p < .05). The differences in luminal size after dilation, measured by the barium pill test, were not significant. Ability to pass the 12-mm pill and absence of dysphagia were correlated. Our results indicate that both devices are effective in relieving dysphagia, but balloons may have a long-term advantage.

Compression of the ulnar nerve at the elbow in association with synovial cysts.

Compression neuropathies around joints in association with synovial cyst formation are rare events. A case of a posttraumatic ulnar nerve palsy in a patient with osteoarthritis of the elbow is presented. At operative exploration of the cubital tunnel, the ulnar nerve was found to be compressed by a synovial cyst. Cyst formation should be considered in determining the etiology of compression neuropathies in patients with posttraumatic and degenerative processes occurring around the joints.

Evaluation of initial surface apposition in porous-coated acetabular components.

The initial surface apposition of the acetabular bone-implant interface was investigated for acetabular components of three different designs: hemispherical with spikes, hemispherical, and threaded hemispherical. Four acetabular components of each design were implanted into fresh anatomic specimen acetabula that were underreamed by 1 mm to the size of the component. Each acetabular specimen then was embedded in methylmethacrylate, sectioned, and examined under magnification. Although acetabular implantation was carefully performed by an experienced surgical team in an idealized laboratory environment, less than complete interface contact was achieved in most cases. Surface contact was limited by five factors: (1) bony anatomy, (2) asymmetric acetabular reaming, (3) retention of the subchondral plate, (4) acetabular component design, and (5) incorrect version of the acetabular component. The bony acetabulum is an incomplete hemisphere because of the acetabular notch and a deep acetabular fossa, and therefore cannot be machined to a perfect hemisphere. Asymmetric reaming occurs because of the anisotropic quality of bone. Retention of the subchondral plate causes incomplete seating of components with spikes or threads. The acetabular design determines the amount of porous coating available for bony apposition and varies depending on the surface area used for screw holes, apical holes, and thread segments. Increased, stable initial surface contact of acetabular components will increase the chances of stable biologic fixation. Improved surface contact will require changes in component design, instrumentation, and technique.

Posterior interosseous nerve: an anatomic study of potential nerve grafts.

Anatomic dissection of the posterior interosseous nerve in 26 cadaver forearms was performed to assess variability in location, diameter, and branching patterns of the nerve. The purpose of our study was to determine the anatomic reliability of the posterior interosseous nerve at the distal forearm level as a potential donor nerve graft for segmental digital nerve loss. The nerve was located in a separate fascicle sheath in the deep radial aspect at the fourth dorsal compartment in all specimens. It ranged from 1 to 5 mm in diameter with one to five fascicles present (15 of 26 specimens had a single fascicle). Ten additional specimens were dissected for assessment of potential length of nerve available for grafting, and this ranged from 5 to 10 cm. These nerves were believed to be of sufficient diameter for grafting of digital-level nerve injuries. There is minimal morbidity when a donor graft is obtained in the same limb as the recipient area, and there is no known donor deficit as a result of posterior interosseous nerve procurement at wrist level.

A study of the frequency of recovery of unexpected Giardia lamblia and Cryptosporidium from duodenal aspirates taken during routine upper endoscopy.

UNLABELLED: In this study, our objective was to determine whether the microscopic examination of duodenal aspirates recovered during routine upper endoscopy in unselected, immunocompetent patients, would disclose unsuspected Giardia lamblia or Cryptosporidium. DESIGN: Prospective, cross-sectional study to determine the prevalence of duodenal parasitosis. SETTING: Endoscopy unit in a university hospital. PATIENTS: One hundred and thirty-one unselected, immunocompetent patients undergoing upper endoscopy. MEASUREMENTS: Microscopic examination of duodenal aspirates, obtained during upper endoscopy. No pathogenic or commensal parasite was identified in any patient. CONCLUSIONS: No case of unsuspected parasitosis was found in the present study. On the basis of our findings, we do not recommend routine collection of duodenal aspirates during upper endoscopy.

Endoscopic carpal tunnel release: a cadaveric study.

Endoscopic carpal tunnel release was performed on 13 fresh-frozen cadavers using the Agee 3-M "Inside Job" Endoscopic Carpal Tunnel Release System, by a surgeon specifically trained in the technique and with a large clinical experience. Independent dissections showed no inadvertent lacerations to nerves, vessels, or tendons. The superficial palmar arch, the communicating branch between the ulnar and median nerves at the palm, and the common digital nerves to the third and fourth web spaces were the structures most at risk. Measurements of the distances between external landmarks were not helpful in accurately predicting the depth of blade insertion. In five of 13 cases there was complete release of the transverse carpal ligament. In four of the remaining eight cases fine fibers of the transverse carpal ligament or fascia connecting the thenar and hypothenar muscles were left over. In the other four cases there was an incomplete release of the transverse carpal ligament. The palmar fascia and more volar structures were preserved in the majority of cases.

A clinical guide to antipsychotic drugs.

Antipsychotic medications have altered the treatment of psychosis. The effect of typical agents is presumed to be associated with dopamine D2-receptor blockade. Response to these drugs can be evaluated by measuring target symptoms. Behavioural symptoms are generally first to respond, followed by affective symptoms, and then symptoms of disturbed cognition and perception. Predictors of response include age of onset, premorbid function, family history, cognitive function, ventricle size, and levels of homovanillic acid. As all conventional antipsychotic medications of comparable dose are generally of equivalent efficacy (with the exception of clozapine), choice is based on past response and the patient's tolerance of adverse effects. When antipsychotic agents are administered in the short term to control agitated dangerous behaviour, they can be given intramuscularly and augmented with benzodiazepines. For the ongoing treatment of psychosis, haloperidol 5 mg/day, or its equivalent, is usually sufficient. Continuation of treatment after an acute episode may be decided on the basis of chronicity of the psychotic illness. Relapse rates are higher when patients do not continue to receive medication. Lower maintenance doses may result in higher relapse rates but fewer adverse effects. Long-acting intramuscular depot preparations may be used to aid compliance in long term therapy. Adverse reactions correlate with potency. High potency drugs (i.e. those with greater D2 postsynaptic receptor affinity) are generally associated with extrapyramidal symptoms, including acute dystonic reactions, akathisia, tardive dyskinesia and Parkinsonism. Neuroleptic malignant syndrome is associated with all neuroleptic drugs. Low potency agents may cause orthostatic hypotension, sedation and anticholinergic effects. Clozapine has been shown to be effective in 30 to 40% of patients resistant to previous treatment. It does not cause extrapyramidal symptoms, but does have side effects similar to those of low potency agents and may cause agranulocytosis; it is therefore reserved for those patients who have not responded to therapy with 2 other agents. Several other atypical drugs are currently being investigated.

Femoral fracture during non-cemented total hip arthroplasty.

A study of the data on 1,318 consecutive non-cemented total hip-replacement arthroplasties revealed thirty-nine intraoperative fractures of the femur (3 per cent), only half of which were diagnosed intraoperatively. The fractures occurred in the proximal region of the femur or at the tip of the stem of the prosthesis. Most were incomplete and minimally displaced, and they did not jeopardize the stability of the femoral component. All complete proximal fractures were stabilized with a four-fifths-coated or fully coated prosthesis to provide distal fixation, and, when diagnosed intraoperatively, were fixed with cerclage wiring. When an incomplete fracture near the tip of the stem was discovered postoperatively and the posterior part of the femoral cortex was intact, a spica cast was applied, and the patient was instructed in protected weight-bearing. For a complete fracture at the tip of the stem, we recommend open reduction and internal fixation. No statistical difference was found with respect to residual pain, the score for walking, or the stability of the implant when we compared the results for the patients who had a fracture with those for the patients who did not. Modifications in surgical technique resulted in a decrease in the incidence of fractures (p less than 0.05).

Endoscopic needle biopsy: a comparative study of forceps biopsy, two different types of needles, and salvage cytology in gastrointestinal cancer.

One of the goals of gastrointestinal endoscopy is to diagnose whether a lesion is malignant. The desire to improve the sensitivity of biopsy-sampling techniques prompted us to compare prospectively the reliability and accuracy of obtaining tissue by forceps biopsy, needle biopsy (21 gauge 13-mm long metal needles versus 18 gauge 20-mm long plastic needles), and salvage cytology in patients with endoscopically suspected malignancy. Samples were obtained in the order of needle biopsy (the order of metal and plastic needle biopsy was randomized), forceps biopsy, followed by salvage cytology. Needle biopsies were obtained by puncturing the lesion under direct vision while aspirating with a syringe. Twenty-three patients with gastrointestinal malignancy were studied (7 esophageal, 4 gastric, and 12 colonic). Forceps biopsies were positive in 18 of 23 (78%), missing 1 gastric and 4 colon malignancies. Metal needle biopsy was positive in 16 of 19 (84%), plastic needle biopsy in 17 of 22 (77%), and salvage cytology in 20 of 22 (91%). Accuracy was increased by a combination of techniques. Endoscopic needle biopsy is a simple and rapid method to evaluate lesions seen at endoscopy and is especially useful in evaluation of submucosal lesions.

Acute compartment syndrome of the thigh. A spectrum of injury.

Twenty-one compartment syndromes of the thigh in seventeen patients were identified for retrospective review. Ten of the compartment syndromes were associated with an ipsilateral femoral fracture; five of these femoral fractures were open. In five patients, the syndrome followed femoral intramedullary stabilization. The remaining eleven syndromes followed blunt trauma to the thigh, prolonged compression by body weight, or vascular injury. The patients who were awake and alert at the time of the examination complained of intense pain in the thigh, and they had neuromuscular deficits. For the patients who could not cooperate with a subjective physical examination because they were under general anesthesia or because of associated injuries, the measurement of compartment pressure assumed a more important diagnostic role. All of the patients had tense swelling of the involved thigh. The predisposing risk factors for the development of compartment syndromes of the thigh, which are common in the multiply injured population, include: systemic hypotension, a history of external compression of the thigh, the use of military antishock trousers, coagulopathy, vascular injury, and trauma to the thigh, with or without a fracture of the femur. In approximately one-half of these patients, a crush syndrome developed, with myoglobinuria, renal failure, and collapse of multiple organ systems. Eight patients (47 per cent) died as a result of multiple injuries. Of the nine patients (ten compartment syndromes) who survived, infection developed at the site of the fasciotomy in six. Follow-up examination revealed marked morbidity, including sensory deficit and motor weakness of the lower extremity.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis and course of nephrogenic ascites.

Nephrogenic ascites is a complex diagnostic problem with poorly understood pathophysiology. Morbidity and eventual mortality from this ongoing problem are significant. The diagnosis of nephrogenic ascites must be established by exclusion. We report the cases of nine patients investigated between 1978 and 1985. Laparoscopy, which was utilized in all nine patients, led to a specific diagnosis in two. We believe that a vigorous diagnostic evaluation, including laparoscopy, is essential in patients with chronic renal failure who develop persistent ascites.

Improved palliation of a respiratory-esophageal fistula with a cuffed esophageal prosthesis.

We report a case in which a traditional prosthesis failed to seal a malignant respiratory-esophageal fistula. Removal of the prosthesis and replacement with a new type with an inflatable cuff provided palliation, and allowed the patient to leave the hospital. The cuffed prosthesis provides a custom fit which should seal fistulous tracts of any shape or size, without causing tissue necrosis.

Cardiac tamponade as a result of endoscopic sclerotherapy: report of a case.

Sclerotherapy was used in the treatment of a patient with actively bleeding esophageal varices. Chest pain and a pericardial friction rub became evident on the day after sclerotherapy and resolved without therapy. Six months later the patient manifested cardiac tamponade which required pericardiectomy. The events of this case suggest that chronic pericarditis with cardiac tamponade was a direct complication of sclerotherapy. This report extends the range of reported complications and emphasizes the importance of follow-up of patients in whom transient pericardial friction rub develops after sclerotherapy.

Nonpathogenic nematodes in gastrointestinal aspirates obtained during endoscopy.

The gastroenterologist must be alert to diagnosing parasitic diseases when collecting intestinal fluid samples or cytologies during endoscopy. Between 1979 and 1982, we identified nematodes in 10 endoscopic specimens. None were Strongyloides stercoralis. We emphasize the importance and technical aspects of distinguishing nonpathogenic nematodes from Strongyloides.

Cimetidine hepatitis.

A 62-year-old man developed asymptomatic anicteric hepatitis during cimetidine therapy for duodenal ulcer disease. Liver biopsy revealed zonal (centrolobular) necrosis, bile stasis, and mononuclear cell infiltration. Electron microscopy featured mitochondrial hyperplasia, giant mitochondria, and liver cell bile inclusions. The diagnosis of cimetidine-related hepatitis was confirmed by re-exposure to cimetidine, which prompted a rapid rise in serum transaminases while under observation in the hospital. Cimetidine hepatitis is rarely reported, and routine monitoring of the patient's liver tests during therapy does not seem cost-effective as a general practice.