Unintentional injury is a major cause of death in children throughout the world and is responsibl... more Unintentional injury is a major cause of death in children throughout the world and is responsible for considerable morbidity. All children are vulnerable to injury because their physical, psychological and behavioural characteristics place them at risk in a largely adult world. The children of the poor are even more vulnerable to injury. This article highlights proven strategies for preventing many
A number of experimental studies in our laboratory have been designed to evaluate the functional ... more A number of experimental studies in our laboratory have been designed to evaluate the functional response of the median nerve at the wrist to various degrees of acute local compression in healthy volunteers and hypertensive patients. The relative significance of ischemia and mechanical deformation in early nerve compression, the critical threshold pressure for nerve conduction impairment, and the clinical sensibility testing system most accurate for evaluating and following patients with acute and chronic compressive neuropathies have been determined using a human model for median nerve compression in the carpal tunnel.Between 40 mmHg and 50 mmHg there exists a critical threshold pressure in normotensive people at which peripheral nerve is acutely jeopardized. The critical pressure threshold is higher in hypertensive patients. The threshold exists at 30 mmHg below diastolic blood pressure and 45 mmHg below mean arterial blood pressure in both normotensive and hypertensive individuals. The correlation between systemic blood pressure and the function of the nerve in response to local compression favors the concept that reduced microvascular perfusion plays the major role in the early stages of low pressure nerve compression. In acute and chronic compression neuropathy, threshold tests (Semmes-Weinstein pressure, vibratory sensibility) detect the earliest abnormalities of nerve function.
Although the overall patterns of deformity may be repetitive in cerebral palsy patients, it is ex... more Although the overall patterns of deformity may be repetitive in cerebral palsy patients, it is extremely important to recognize that nothing replaces a careful examination of the individual patient and an individualized plan of approach. Our mistakes are rarely caused by technical errors, and we should not attribute our failures to the patient and resort to such statements as, "tendon transfer in cerebral palsy is unpredictable." Instead, we should feel confident that although a normal extremity will never result after operative treatment, contractures and spasticity can be diminished in such a way to make possible certain coordinated actions that will help our patients in their activities of daily living.
Sickle cell anemia and Kienböck's disease occurred in an 18-year-old man. The association... more Sickle cell anemia and Kienböck's disease occurred in an 18-year-old man. The association of the two conditions seems not to have been previously reported.
We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twent... more We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twenty-three hands of twenty patients with idiopathic carpal-tunnel syndrome who underwent carpal tunnel release. Tests of sensibility included the threshold tests (vibrometry, 256-cycles-per-second vibration, and Semmes-Weinstein monofilaments) and one innervation-density test (two-point discrimination). In addition the wrist-flexion test, nerve-percussion test, and tourniquet test were performed preoperatively. Only five of the twenty-three hands had abnormal two-point discrimination and each of these also had markedly abnormal threshold-test values. Nineteen of twenty-three hands preoperatively had decreased sensibility detected by both Semmes-Weinstein monofilament testing and vibrometry. Six weeks after carpal tunnel release, all of the hands demonstrated improvement on threshold testing, and 65 per cent had normal values.
A retrospective study was undertaken to determine the efficacy of carpal tunnel decompression in ... more A retrospective study was undertaken to determine the efficacy of carpal tunnel decompression in patients with advanced carpal tunnel syndrome. The criteria for inclusion in this study were unobtainable median sensory-evoked response and absent or prolonged median motor distal latency. Fifteen hands in 13 patients met these criteria. All patients had symptoms, including pain, weakness, or decreased sensation. Postoperative follow-up averaged 27 months. Symptomatic improvement was obtained in 14 of the 15 hands, and sensory-evoked response improved in 13 hands. Preoperative thenar atrophy was present in 10 of the 15 hands and was completely resolved in 2 of the 10 patients. These results indicate that carpal tunnel decompression is of benefit to patients with severe carpal tunnel syndrome. Long-standing symptoms, thenar atrophy, virtual anesthesia, and the absence of demonstrable sensory and motor-evoked responses are not contraindications to surgery.
The Journal of bone and joint surgery. American volume, 1984
We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twent... more We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twenty-three hands of twenty patients with idiopathic carpal-tunnel syndrome who underwent carpal tunnel release. Tests of sensibility included the threshold tests (vibrometry, 256-cycles-per-second vibration, and Semmes-Weinstein monofilaments) and one innervation-density test (two-point discrimination). In addition the wrist-flexion test, nerve-percussion test, and tourniquet test were performed preoperatively. Only five of the twenty-three hands had abnormal two-point discrimination and each of these also had markedly abnormal threshold-test values. Nineteen of twenty-three hands preoperatively had decreased sensibility detected by both Semmes-Weinstein monofilament testing and vibrometry. Six weeks after carpal tunnel release, all of the hands demonstrated improvement on threshold testing, and 65 per cent had normal values.
The Journal of Trauma: Injury, Infection, and Critical Care, 1984
Intracarpal canal interstitial fluid pressures were determined in the wrists of 22 patients with ... more Intracarpal canal interstitial fluid pressures were determined in the wrists of 22 patients with 23 Colles' fractures. Mean values were 18 mm Hg in neutral wrist position, 27 mm Hg in 20 degrees flexion, 47 mm Hg in 40 degrees flexion, and 35 mm Hg in 20 degrees extension. Ten of 23 wrists (45%) had pressures greater than 40 mm Hg in 40 degrees of flexion. Because of the high incidence of median neuropathy associated with immobilization of wrist fractures in a position of marked flexion, an awareness of the magnitude of increased interstitial fluid pressure should lead to alternative methods of treatment in many cases.
An experimental model for the study of canine flexor tendon adhesions was designed using a standa... more An experimental model for the study of canine flexor tendon adhesions was designed using a standardized crush-abrasion injury, meticulous sheath closure, and three-week limb immobilization. Ten animals in the experimental protocol were evaluated for visible adhesion formation. With use of a flexor tendon adhesion rating scale, consistent adhesion formation was documented with an average score of 10.4 +/- 2.1 (range, 0 to 12). Five additional animals had biomechanical testing. Applying an increasing load to the proximally divided profundus tendon (0 to 10 Newtons), it was found that the angle of distal interphalangeal joint motion and the displacement of the toe were significantly decreased, and the work generated significantly increased in the experimental versus control digits (p less than 0.05). The consistent production of visible adhesions thus correlates with biomechanical impairments in toe motion and work. The study of agents aimed at diminishing flexor tendon adhesions will thus be facilitated by this reliable model. Systemic or intrasheath administration of agents will be possible.
The dorsal retinaculum of the wrist consists of two layers: the supratendinous and the infratendi... more The dorsal retinaculum of the wrist consists of two layers: the supratendinous and the infratendinous. The infratendinous layer is limited to an area deep to the ulnar three compartments. There are six compartments for the tendons dorsal to the wrist separated by six longitudinal vertical septa. Each septum originates from the supratendinous retinaculum and inserts onto the radius. The sixth compartment for the extensor carpi ulnaris is complex. The tendon of the extensor carpi ulnaris is enclosed in an independent fibrous tunnel formed by the supratendinous retinaculum superiorly, the infratendinous retinaculum inferiorly, the sixth septum laterally, and the ulnar insertion of the retinaculum reinforced by longitudinal fibers called the "linea jugata" medially. Our findings support the concept of an adaptable dynamic collateral ligament system rather than the traditional radial and ulnar collateral ligaments.
Wolters Kluwer Health may email you for journal alerts and information, but is committed to maint... more Wolters Kluwer Health may email you for journal alerts and information, but is committed to maintaining your privacy and will not share your personal information without your express consent. For more information, please refer to our Privacy Policy. ... Skip Navigation Links Home > August ...
Computed tomography followed by sectional radiography and photography as performed on eight cadav... more Computed tomography followed by sectional radiography and photography as performed on eight cadaveric specimens in order to define the anatomy and normal motion of both the proximal and the distal radioulnar articulations. Osseous landmarks were defined that allowed measurement of rotation at the glenohumeral, proximal radioulnar and distal radioulnar joints as well as rotation between humerus and radius and between humerus and ulna. Findings included the absence of independent ulnar rotation and the presence of normal translatory motion at the distal radioulnar articulation that may be misinterpreted as evidence of subluxation of the distal ulna.
Computed tomography and sectional radiography and photography were performed on eight cadaveric w... more Computed tomography and sectional radiography and photography were performed on eight cadaveric wrist specimens in order to define the soft tissue structures of the normal wrist. Three specific levels were analyzed in detail: the levels of the distal radioulnar joint, of the pisotriquetral joint, and of the hook of the hamate. All soft tissues, with the exception of arteries and veins, were well demonstrated with computed tomography. In particular, the contents of both Guyon's canal and the carpal tunnel could be delineated. The position of the extensor carpi ulnaris tendon and sheath could also be evaluated. Contrast opacification of the flexor tendon sheaths and palmar synovial sacs did not contribute to the analysis. Computed tomography appears to be an important imaging modality in the evaluation of significant clinical problems, including the carpal tunnel and ulnar tunnel syndromes and subluxation of the extensor carpi ulnaris tendon.
Unintentional injury is a major cause of death in children throughout the world and is responsibl... more Unintentional injury is a major cause of death in children throughout the world and is responsible for considerable morbidity. All children are vulnerable to injury because their physical, psychological and behavioural characteristics place them at risk in a largely adult world. The children of the poor are even more vulnerable to injury. This article highlights proven strategies for preventing many
A number of experimental studies in our laboratory have been designed to evaluate the functional ... more A number of experimental studies in our laboratory have been designed to evaluate the functional response of the median nerve at the wrist to various degrees of acute local compression in healthy volunteers and hypertensive patients. The relative significance of ischemia and mechanical deformation in early nerve compression, the critical threshold pressure for nerve conduction impairment, and the clinical sensibility testing system most accurate for evaluating and following patients with acute and chronic compressive neuropathies have been determined using a human model for median nerve compression in the carpal tunnel.Between 40 mmHg and 50 mmHg there exists a critical threshold pressure in normotensive people at which peripheral nerve is acutely jeopardized. The critical pressure threshold is higher in hypertensive patients. The threshold exists at 30 mmHg below diastolic blood pressure and 45 mmHg below mean arterial blood pressure in both normotensive and hypertensive individuals. The correlation between systemic blood pressure and the function of the nerve in response to local compression favors the concept that reduced microvascular perfusion plays the major role in the early stages of low pressure nerve compression. In acute and chronic compression neuropathy, threshold tests (Semmes-Weinstein pressure, vibratory sensibility) detect the earliest abnormalities of nerve function.
Although the overall patterns of deformity may be repetitive in cerebral palsy patients, it is ex... more Although the overall patterns of deformity may be repetitive in cerebral palsy patients, it is extremely important to recognize that nothing replaces a careful examination of the individual patient and an individualized plan of approach. Our mistakes are rarely caused by technical errors, and we should not attribute our failures to the patient and resort to such statements as, "tendon transfer in cerebral palsy is unpredictable." Instead, we should feel confident that although a normal extremity will never result after operative treatment, contractures and spasticity can be diminished in such a way to make possible certain coordinated actions that will help our patients in their activities of daily living.
Sickle cell anemia and Kienböck's disease occurred in an 18-year-old man. The association... more Sickle cell anemia and Kienböck's disease occurred in an 18-year-old man. The association of the two conditions seems not to have been previously reported.
We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twent... more We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twenty-three hands of twenty patients with idiopathic carpal-tunnel syndrome who underwent carpal tunnel release. Tests of sensibility included the threshold tests (vibrometry, 256-cycles-per-second vibration, and Semmes-Weinstein monofilaments) and one innervation-density test (two-point discrimination). In addition the wrist-flexion test, nerve-percussion test, and tourniquet test were performed preoperatively. Only five of the twenty-three hands had abnormal two-point discrimination and each of these also had markedly abnormal threshold-test values. Nineteen of twenty-three hands preoperatively had decreased sensibility detected by both Semmes-Weinstein monofilament testing and vibrometry. Six weeks after carpal tunnel release, all of the hands demonstrated improvement on threshold testing, and 65 per cent had normal values.
A retrospective study was undertaken to determine the efficacy of carpal tunnel decompression in ... more A retrospective study was undertaken to determine the efficacy of carpal tunnel decompression in patients with advanced carpal tunnel syndrome. The criteria for inclusion in this study were unobtainable median sensory-evoked response and absent or prolonged median motor distal latency. Fifteen hands in 13 patients met these criteria. All patients had symptoms, including pain, weakness, or decreased sensation. Postoperative follow-up averaged 27 months. Symptomatic improvement was obtained in 14 of the 15 hands, and sensory-evoked response improved in 13 hands. Preoperative thenar atrophy was present in 10 of the 15 hands and was completely resolved in 2 of the 10 patients. These results indicate that carpal tunnel decompression is of benefit to patients with severe carpal tunnel syndrome. Long-standing symptoms, thenar atrophy, virtual anesthesia, and the absence of demonstrable sensory and motor-evoked responses are not contraindications to surgery.
The Journal of bone and joint surgery. American volume, 1984
We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twent... more We evaluated the sensibility of the hand preoperatively and at intervals postoperatively in twenty-three hands of twenty patients with idiopathic carpal-tunnel syndrome who underwent carpal tunnel release. Tests of sensibility included the threshold tests (vibrometry, 256-cycles-per-second vibration, and Semmes-Weinstein monofilaments) and one innervation-density test (two-point discrimination). In addition the wrist-flexion test, nerve-percussion test, and tourniquet test were performed preoperatively. Only five of the twenty-three hands had abnormal two-point discrimination and each of these also had markedly abnormal threshold-test values. Nineteen of twenty-three hands preoperatively had decreased sensibility detected by both Semmes-Weinstein monofilament testing and vibrometry. Six weeks after carpal tunnel release, all of the hands demonstrated improvement on threshold testing, and 65 per cent had normal values.
The Journal of Trauma: Injury, Infection, and Critical Care, 1984
Intracarpal canal interstitial fluid pressures were determined in the wrists of 22 patients with ... more Intracarpal canal interstitial fluid pressures were determined in the wrists of 22 patients with 23 Colles' fractures. Mean values were 18 mm Hg in neutral wrist position, 27 mm Hg in 20 degrees flexion, 47 mm Hg in 40 degrees flexion, and 35 mm Hg in 20 degrees extension. Ten of 23 wrists (45%) had pressures greater than 40 mm Hg in 40 degrees of flexion. Because of the high incidence of median neuropathy associated with immobilization of wrist fractures in a position of marked flexion, an awareness of the magnitude of increased interstitial fluid pressure should lead to alternative methods of treatment in many cases.
An experimental model for the study of canine flexor tendon adhesions was designed using a standa... more An experimental model for the study of canine flexor tendon adhesions was designed using a standardized crush-abrasion injury, meticulous sheath closure, and three-week limb immobilization. Ten animals in the experimental protocol were evaluated for visible adhesion formation. With use of a flexor tendon adhesion rating scale, consistent adhesion formation was documented with an average score of 10.4 +/- 2.1 (range, 0 to 12). Five additional animals had biomechanical testing. Applying an increasing load to the proximally divided profundus tendon (0 to 10 Newtons), it was found that the angle of distal interphalangeal joint motion and the displacement of the toe were significantly decreased, and the work generated significantly increased in the experimental versus control digits (p less than 0.05). The consistent production of visible adhesions thus correlates with biomechanical impairments in toe motion and work. The study of agents aimed at diminishing flexor tendon adhesions will thus be facilitated by this reliable model. Systemic or intrasheath administration of agents will be possible.
The dorsal retinaculum of the wrist consists of two layers: the supratendinous and the infratendi... more The dorsal retinaculum of the wrist consists of two layers: the supratendinous and the infratendinous. The infratendinous layer is limited to an area deep to the ulnar three compartments. There are six compartments for the tendons dorsal to the wrist separated by six longitudinal vertical septa. Each septum originates from the supratendinous retinaculum and inserts onto the radius. The sixth compartment for the extensor carpi ulnaris is complex. The tendon of the extensor carpi ulnaris is enclosed in an independent fibrous tunnel formed by the supratendinous retinaculum superiorly, the infratendinous retinaculum inferiorly, the sixth septum laterally, and the ulnar insertion of the retinaculum reinforced by longitudinal fibers called the "linea jugata" medially. Our findings support the concept of an adaptable dynamic collateral ligament system rather than the traditional radial and ulnar collateral ligaments.
Wolters Kluwer Health may email you for journal alerts and information, but is committed to maint... more Wolters Kluwer Health may email you for journal alerts and information, but is committed to maintaining your privacy and will not share your personal information without your express consent. For more information, please refer to our Privacy Policy. ... Skip Navigation Links Home > August ...
Computed tomography followed by sectional radiography and photography as performed on eight cadav... more Computed tomography followed by sectional radiography and photography as performed on eight cadaveric specimens in order to define the anatomy and normal motion of both the proximal and the distal radioulnar articulations. Osseous landmarks were defined that allowed measurement of rotation at the glenohumeral, proximal radioulnar and distal radioulnar joints as well as rotation between humerus and radius and between humerus and ulna. Findings included the absence of independent ulnar rotation and the presence of normal translatory motion at the distal radioulnar articulation that may be misinterpreted as evidence of subluxation of the distal ulna.
Computed tomography and sectional radiography and photography were performed on eight cadaveric w... more Computed tomography and sectional radiography and photography were performed on eight cadaveric wrist specimens in order to define the soft tissue structures of the normal wrist. Three specific levels were analyzed in detail: the levels of the distal radioulnar joint, of the pisotriquetral joint, and of the hook of the hamate. All soft tissues, with the exception of arteries and veins, were well demonstrated with computed tomography. In particular, the contents of both Guyon's canal and the carpal tunnel could be delineated. The position of the extensor carpi ulnaris tendon and sheath could also be evaluated. Contrast opacification of the flexor tendon sheaths and palmar synovial sacs did not contribute to the analysis. Computed tomography appears to be an important imaging modality in the evaluation of significant clinical problems, including the carpal tunnel and ulnar tunnel syndromes and subluxation of the extensor carpi ulnaris tendon.
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