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Biomedical subjects

J R Sanger

Publications and source records attributed to J R Sanger.

At least 19 recordsLinked to original sources
PubMed2001

Gait analysis in rats with peripheral nerve injury.

Rats are commonly used to study peripheral nerve repair and grafting. The traditional footprint method to assess functional recovery is messy, indirect, and not useful when contractures develop in the animal model. The aim of the present study was to establish an accurate, reproducible, but simple, method to assess dynamic limb function. The basic quantitative aspects of a normal gait were characterized from 59 recorded walks in 23 rats. The video was digitized and analyzed frame by frame on a personal computer. Seven parameters of the gait were assessed: (1) walking speed; (2) stance phase, swing phase and right to left stance/swing ratio; (3) step length and step length ratio; (4) ankle angles at terminal stance and midswing; (5) tail height; (6) midline deviation; and (7) tail deviation. These gait parameters were then applied to groups of animals with sciatic (group S), tibial (group T), and peroneal (group P) nerve injuries. A discriminant analysis was performed to analyze each parameter and to compute a functional score. We found that the video gait analysis was superior to the footprint method and believe it will be very useful in future studies on peripheral nerve injury.

Animals↗
PubMed2001

Salvage of ischemic digits using a lateral arm fascial flap.

Four patients underwent microvascular transfer of a lateral arm fascial flap to salvage severely ischemic digits by means of induction of neovascularization. The cause of the digital ischemia was direct trauma (crush injury) in one patient and chronic embolic phenomena (proximal arterial occlusion) in three patients. None of the patients had responded to traditional therapy, including treatment with one or more of the following: anticoagulation, lytic therapy, oral vasodilators, digital sympathectomy, and vein bypass grafting. Each patient underwent noninvasive (Doppler ultrasound, digital pressures, digital temperatures, vascular refill) and invasive (angiogram) vascular assessment preoperatively. After microvascular transfer of the lateral arm fascial flap, all patients reported symptomatic relief, and objective improvements were documented by both noninvasive and invasive assessment criteria. One patient developed a seroma at the donor site; another experienced a late complication of thrombosis of the flap after his wound dehisced. A 6-month follow-up evaluation demonstrated neovascular collateralization and stable improvement without regression in the remaining patients. The authors present their clinical experience and propose a treatment algorithm for patients with chronic digital ischemia.

Adult↗
PubMed2000

Lateral arm fascial flap: microarterial anatomy and potential clinical applications.

Previously, muscle flaps and the omentum have been used to indirectly vascularize tissues. Induction of synangiogenesis, or indirect vascularization through the formation of collateral vessels, occurs through the development of vascular connections at the interface between the donor and recipient tissues. Unfortunately, muscle and omental flaps are bulky and, when used to salvage ischemic hands and digits, may limit digital range of motion. Additionally, disadvantages to using omentum include a requirement for an intraabdominal procedure and a lack of subsequent donor tissue if the contralateral limb becomes involved at a later time. The purpose of this anatomic study was to develop a customized lateral arm fascial flap (LAFF) which may be used for flap prefabrication or synangiogenesis of non-bypassable ischemia. Detailed anatomic dissections were performed to more thoroughly define the microvascular anatomy of the LAFF. Computer analysis of the data was performed to demonstrate the potential clinical application of using the LAFF. Dissections revealed a consistent pattern of vessels branching within the lateral arm fascia and to the neighboring musculature. In order to optimize the surgical use of available tissue, computer-aided design techniques were used to model a reliable fascial free flap for inducing synangiogenesis while imparting minimal donor-site morbidity. Anatomic studies of the LAFF revealed pitfalls in flap dissection, while computer-generated models illustrated the detailed microarterial anatomy of the LAFF and potential limitations in flap design. Potential clinical applications for use of this low-profile fasciovascular conduit are noted.

Arm↗
PubMed2000

Tongue reconstruction with a combined brachioradialis-radial forearm flap.

Total glossectomy adversely affects speech and swallowing, and subsequent reconstruction results in limited functional return. The radial forearm flap has been reliably used to resurface glossectomy defects, but has limited bulk with which to aid in palatoglossal contact for speech. The authors have modified the forearm flap by incorporating a segment of brachioradialis muscle, to increase bulk posteriorly and to aid in speech. Sufficient muscle perforators arise from the proximal brachial artery and enter the brachioradialis to permit transfer of the muscle with the fasciocutaneous forearm flap as a single free-flap unit. The muscle is folded onto itself and enclosed within the forearm flap skin to create a neotongue. Coaptation of the antebrachial cutaneous nerves can provide a senate flap. Successful transfer of the combined brachioradialis/forearm flap in a patient who had undergone total glossectomy resulted in a neotongue good shape. Speech was rated good by a speech pathologist, and palatoglossal contact was observed on cineoradiograph. No functional loss at the donor site occurred. Inclusion of the brachioradialis muscle with the radial forearm flap as a combined unit results in a neotongue with good form and increased bulk posteriorly at the base, compared to a standard fasciocutaneous flap alone. This is a useful variation of the forearm flap. Sensory return is possible if the medial and/or lateral antebrachial cutaneous nerves of the flap are coapted to the lingual nerve.

Carcinoma, Squamous Cell↗
PubMed2000

Psychological adjustment in children after traumatic disfiguring injuries: a 12-month follow-up.

The psychological adjustment of 57 children (age range, 3 to 12 years) who sustained mutilating traumatic injuries to the face or upper or lower extremities was assessed over a 12-month interval. The injuries had occurred as a result of boating, lawn mower, or home accidents or dog bites. Within 5 days of the traumatic event, 98 percent of the children were symptomatic for posttraumatic stress disorder, depression, or anxiety. One month after the injury, 82 percent were symptomatic. Symptom frequency had declined by the time of the 3-month and 6-month evaluations, but 44 percent of the children continued to report symptoms at 12-month follow-up visits, and 21 percent met the diagnostic criteria for posttraumatic stress disorder. Typical symptoms included flashbacks, fear of re-injury, mood disorders, body-image changes secondary to disfigurement, sleep disturbances, and anxiety. These findings support the importance of psychological evaluation and treatment of children who suffer mutilating injuries that require the attention of plastic surgeons.

Accidents, Home↗
PubMed1999

Subcutaneous tissue emphysema of the hand secondary to noninfectious etiology: a report of two cases.

Subcutaneous emphysema of the hand can be benign and noninfectious in origin. Emphysema from gas-forming organisms is associated with systemic symptoms, whereas benign subcutaneous emphysema is not. High-pressure pneumatic tool injuries are a well-known cause of subcutaneous emphysema. Minor wounds in the web space skin may result in a transport of air across the defect, acting like a ball valve mechanism to trap and then force the air into the subcutaneous tissue, as illustrated by 1 of our patients. In the second patient, use of a high-vibration tool without apparent breach of skin was associated with extensive subcutaneous emphysema. The benign nature of the emphysema was revealed by a lack of local pain and inflammation in the presence of extensive crepitus and a lack of systemic symptoms. A noninfectious cause should always be considered. This may prevent unnecessary surgical intervention, which occurred in 1 of the 2 cases presented here.

Adult↗
PubMed1999

The hand injury severity scoring system and workers' compensation cases in Wisconsin, USA.

The Hand Injury Severity Score was retrospectively applied to a group of workers' compensation cases in Wisconsin, USA. A statistically significant correlation was found between the score and the time interval between injury and the end of healing. These results are comparable to the findings in the original study of Campbell and Kay (1996). We provide some suggestions for further development of this scoring system.

Evaluation Studies as Topic↗
PubMed1999

False-positive radiographic diagnosis of breast implant rupture because of breast abscess.

A case of a periprosthetic abscess simulating breast implant rupture is presented. Both clinical findings and film-screen mammography suggested extravasation of a radiodense material adjacent to an implant. Ultrasonography was thought to confirm the extraluminal silicone. However, at surgery the mass was found to be a breast abscess that had herniated through the capsule. The double-lumen implant outer saline-filled chamber had deflated, but the silicone-containing inner chamber was intact. Magnetic resonance imaging would have distinguished between abscess and silicone.

Abscess↗
PubMed1999

The innervated gracilis musculocutaneous flap for total tongue reconstruction.

A functional neotongue following total glossectomy requires both soft-tissue bulk and reconstruction of muscle function. We used innervated transverse gracilis musculocutaneous flaps to reconstruct total glossectomy defects in eight patients. The obturator nerve to the gracilis muscle was approximated to the hypoglossal nerve to reinnervate the gracilis muscle by using microsurgical technique. The cutaneous paddle of the gracilis flap easily supplies sufficient bulk to replace the total glossectomy defect. Follow-up of patients ranged from 3 to 47 months. All patients were able to resume oral feeding. Electromyographic studies performed on one patient showed reinnervation of the flap with active elevation of the posterior pharynx. Ultimately, seven patients died because of recurrence of their disease. The innervated gracilis musculocutaneous flap may benefit patients who have a total glossectomy by allowing them to achieve a more functional recovery.

Deglutition↗
PubMed1998

Superior preservation of the staphylococcal glycocalyx with aldehyde-ruthenium red and select lysine salts using extended fixation times.

The utility of lysine-based aldehyde-ruthenium red fixatives for the preservation and/or staining of the fibrous staphylococcal glycocalyx was improved by substitution of alternative forms of lysine for the free amino form. Paraformaldehyde-glutaraldehyde fixatives containing alternative lysines, with or without ruthenium red, were compared at short 20-minute prefixation times and at extended overnight fixation times. Although inclusion of paraformaldehyde made longer fixation times possible, the length of time for "safe" fixation varied per sample and could not be predicted. All alternative lysine forms permitted fixation of at least 24 hours without sample loss. The L-lysine monohydrochloride or L-lysine acetate forms permitted longer fixation times than the L-lysine free amino form, and they had comparable or better preservation of the staphylococcal glycocalyx. Thus, the usefulness of aldehyde-lysine-based fixatives with minor changes has been enhanced.

Aldehydes↗
PubMed1998

Myelinated sensory and alpha motor axon regeneration in peripheral nerve neuromas.

Histochemical staining for carbonic anhydrase and cholinesterase (CE) activities was used to analyze sensory and motor axon regeneration, respectively, during neuroma formation in transected and tube-encapsulated peripheral nerves. Median-ulnar and sciatic nerves in the rodent model permitted testing whether a 4 cm greater distance of the motor neuron soma from axotomy site or intrinsic differences between motor and sensory neurons influenced regeneration and neuroma formation 10, 30, and 90 days later. Ventral root radiculotomy confirmed that CE-stained axons were 97% alpha motor axons. Distance significantly delayed axon regeneration. When distance was negligible, sensory axons grew out sooner than motor axons, but motor axons regenerated to a greater quantity. These results indicate regeneration differences between axon subtypes and suggest more extensive branching of motor axons within the neuroma. Thus, both distance from injury site to soma and inherent motor and sensory differences should be considered in peripheral nerve repair strategies.

Animals↗
PubMed1998

Silicone gel enhances the development of autoimmune disease in New Zealand black mice but fails to induce it in BALB/cAnPt mice.

Anecdotal evidence links silicone gel breast implants with the development of autoimmune connective tissue disease in women. To investigate whether silicone gel is capable of directly inducing and/or enhancing the development of autoimmune disease, female BALB/cAnPt (BALB/c) and New Zealand Black (NZB) mice were injected subcutaneously with silicone gel, pristane, a nonmetabolizable substance that can cause plasmacytomas in BALB/c and NZB mice, or saline and monitored for the development of glomerulonephritis and autoantibody production. NZB, but not BALB/c, mice spontaneously develop autoantibodies and an autoimmune hemolytic anemia by 12 months of age. Over a period of 10 months, biweekly screening for proteinuria revealed increases in urinary protein in NZB mice that received multiple injections of either silicone gel or pristane. In contrast, urinary protein was unaffected in identically treated BALB/c mice. Although, silicone gel had no effect on serum titers of antierythrocyte antibodies in NZB mice, the hematocrits were significantly decreased. Moreover, silicone gel both increased the concentration of IgM anti-type I collagen antibodies and skewed the immunofluorescent staining pattern of serum autoantibodies on HEp-2 cells. In contrast, silicone gel failed to induce the production of anti-erythrocyte or antinuclear antibodies in BALB/c mice and induced only slight increases in IgG anti-type I collagen antibodies. These results suggest that silicone gel can exacerbate the development of autoimmune disease in autoimmune NZB mice, but fails to induce disease in normal BALB/c mice. This is consistent with several epidemiological studies failing to demonstrate an increase in the incidence of autoimmune disease in women with breast implants. However, because silicone gel was able to exacerbate autoimmune disease in NZB mice, it may play a similar role in the development of autoimmune disease in a small percentage of women who are genetically susceptible to such diseases.

Animals↗
PubMed1998

The detailed anatomy of the palmar cutaneous nerves and its clinical implications.

The forearms and hands of 40 fresh-frozen cadavers were dissected under the microscope to study the palmar cutaneous branch of the median nerve (PCBm) and the palmar cutaneous branch of the ulnar nerve (PCBu). Branches of the PCBm innervating the scaphoid were typically found, but in no specimen did we find a 'typical' cutaneous branch of the ulnar nerve. According to our findings, standard incisions for open carpal tunnel release carry a significant risk of damaging branches of the PCBm or PCBu. The chance of injury to these sensory nerves can be minimized by using a short incision in the proximal palm or a twin incision approach, which we describe. Because the PCBm is closely associated with the ulnar side of the flexor carpi radialis (FCR) sheath, this sheath should be opened on the radial side during harvest of the FCR tendon for transfer. When transferring the palmaris longus tendon, it should be cut proximal to the distal wrist crease to avoid possible damage to the PCBm.

Cadaver↗
PubMed1998

Analysis of the distribution of cutaneous perforators in cutaneous flaps.

An anatomic and statistical analysis was performed on the distribution of cutaneous perforators that perfuse the scapular, radial forearm, and lateral arm cutaneous flaps. Perforators were categorized as direct, terminal, and intransitive, depending upon perforator origin and termination site relative to the source artery. Statistical cluster analysis of perforator distributions was performed to determine the regions in which cutaneous perforators are consistently found. The scapular and radial forearm flaps could be divided into up to three well-perfused segments. The analysis predicted the possibility of dividing the lateral arm flap into as many as seven segments while maintaining perfusion. Clinical applications of this method for preoperative flap design and elevation as well as final results are shown.

Arm↗
PubMed1998

Sequential transfer of free flap to two defects.

This case report describes the use of a single lateral arm flap sequentially transferred to two defects in a bilateral hand injury. We believe this is a novel approach in reconstructing defects in bilateral hands when a staged reconstruction is planned.

Adult↗
PubMed1997

Paraformaldehyde effect on ruthenium red and lysine preservation and staining of the staphylococcal glycocalyx.

The utility of lysine in glutaraldehyde-ruthenium red fixatives for the preservation and/or staining of the fibrous staphylococci glycocalyx was improved by inclusion of paraformaldehyde. Short, 20 min prefixation times for paraformaldehyde-glutaraldehyde fixatives containing lysine, with or without ruthenium red, were compared to an extended overnight fixation. Samples were often lost in fixatives that did not contain paraformaldehyde at extended fixation times hampering the effective use of these fixatives for clinical or environmental applications. Inclusion of paraformaldehyde in the fixation with lysine permitted longer fixation times as well as stabilized the staphylococcal glycocalyx. Thus, the technical usefulness of fixatives employing lysine was significantly improved.

Fixatives↗
PubMed1997

Anatomy of the intermetacarpal ligaments of the carpometacarpal joints of the fingers.

In this study, the structure of the retaining ligaments between the proximal metacarpal bones of the fingers was defined. Anatomic dissections were performed on 10 fresh cadavers. Four separate ligaments were found: a dorsal metacarpal ligament, a palmar metacarpal ligament, and 2 interosseous ligaments oriented in a V-shaped configuration. The V-shaped interosseous ligaments were found to be the strongest; along with the palmar and dorsal intermetacarpal ligaments, they form a very strong connection between the bases of the adjacent metacarpals.

Carpal Bones↗