Biomedical subjects

M D Rooks

Publications and source records attributed to M D Rooks.

15 recordsLinked to original sources

PubMed1997

Rock climbing injuries.

Three-quarters of elite and recreational sport climbers will suffer upper extremity injuries. Approximately 60% of these injuries will involve the hand and wrist, the other 40% will be equally divided between the elbow and the shoulder. Most injuries will be tendonopathies secondary to strains, microtrauma or flexor retinacular irritation. However, up to 30% of these injuries in up to 50% of elite climbers will involve the proximal interphalangeal (PIP) region. These injuries are more serious and consist of varying degrees of flexor digitorum sublimis insertional strains, digital fibro-osseous sheath ruptures and PIP joint collateral ligament strains. Early changes in climbing schedules, stretching and exercise habits, and protective digital taping are necessary to protect and rehabilitate these athletes.

Finger Injuries↗

PubMed1994

Comparative study of intraarterial and intravenous anticoagulants in microvascular anastomoses.

Using a rat femoral artery crush-avulsion model previously described by the authors (Rooks et al.: Microsurgery 14: 130-134, 1993), we analyzed the relative efficacy of intraarterially delivered anticoagulants against similar systemically administered intravenous anticoagulants with double blinded experimentation. The model uses a standardized crush of approximately 0.3 J and a standardized avulsion. This is followed by vascular stasis for 90 seconds after vessel repair. All rats were limited to 175 to 225 gm in weight to control vessel size. Urokinase, heparin sodium, and dextran (40,000 Dalton) were evaluated in this study. A statistically significant (p-value = 0.02) increase in urokinase efficacy was found with intraarterial delivery. (Patency rate increased from 40% to 100%). No advantage to intraarterial delivery was evident with either dextran or heparin. There was a dose related improvement in patency with heparin that was unaffected by delivery route. (Patency increased from 30% to 80% with a statistical p-value of 0.018.)

Anastomosis, Surgical↗

PubMed1994

Compartment pressure in association with closed tibial fractures. The relationship between tissue pressure, compartment, and the distance from the site of the fracture.

We studied twenty-five consecutive patients who had a closed tibial fracture to determine whether there was a relationship between compartment pressure and the distance at which the pressure was measured from the site of the fracture. Tissue pressure was measured in all four compartments of the leg at the level of the fracture and at five-centimeter increments proximal and distal to the fracture. The peak pressure was usually found at the level of the fracture and was always located within five centimeters of the fracture. The highest pressures were recorded in the anterior and the deep posterior compartments in twenty patients, including all five of those who had had a fasciotomy. The measured pressure decreased steadily when sampled at increasing distances proximal and distal to the site of the highest recorded pressure. Decreases of twenty millimeters of mercury (2.67 kilopascals) five centimeters adjacent to the site of the peak pressure were common. Compartment syndrome was diagnosed in five patients on the basis of clinical findings, and the diagnosis was confirmed when peak compartment pressures of more than the critical threshold (within twenty millimeters of mercury [2.67 kilopascals] of the diastolic blood pressure) were recorded. Three of these five patients had measured pressures that were less than the critical threshold within five centimeters of the site of the peak pressure. Failure to measure tissue pressure within a few centimeters of the zone of peak pressure may result in a serious underestimation of the maximum compartment pressure. Our results suggest that measurements should be performed in both the anterior and the deep posterior compartments at the level of the fracture as well as at locations proximal and distal to the zone of the fracture to determine reliably the location of the highest tissue pressure in a lower extremity when a compartment syndrome is suspected clinically. The highest pressure should be used in the decision-making process.

Adult↗

PubMed1993

Refinement of the rat crush-avulsion femoral artery injury model.

A model for studying arterial crush-avulsion injuries in the rat is described. The model uses a standardized crush of approximately 0.3 joules and a standardized avulsion. The crush is accomplished by gravity acceleration of a 400 g weight over a distance of 7.5 cm. The weight impacts an anvil over the artery distributing the force of the impact over a 10 mm length of the vessel. The avulsion is accomplished by a hemostat attached to a second, 120g weight. Vascular stasis for 90 sec after vessel repair in a 175-225 g rat will consistently result in an 80% anastomotic failure. The model allows evaluation of anticoagulant effects singly or in combination. Agents may be given either systemically by intravenous route or locally by intraarterial route.

Anastomosis, Surgical↗

PubMed1993

Precision of suture placement with microscope- and loupe-assisted anastomoses.

Twenty-eight anastomoses involving seven surgeons were done on 2 mm Gortex vascular prostheses to test the effect of magnification on the precision of suture placement. One-half were done with 3.5-4x prism loupe magnification and the other one-half with 8-30x microscope magnification. The variability of suture placement (defined here as precision) was measured in a blinded fashion. The mean suture puncture to prosthesis edge measurement for the microscope-assisted group was approximately 0.03 mm closer to the edge. The variability from the mean for the microscope-assisted group was approximately 0.01 mm less than that for the loupe-assisted group. This difference was statistically significant at a P value of 0.0123.

Anastomosis, Surgical↗

PubMed1993

Myoelectric prostheses. A long-term follow-up and a study of the use of alternate prostheses.

Forty-four patients who had had a total of forty-seven amputations of an upper extremity and who had had a myoelectric prosthesis for more than two years were evaluated retrospectively for the amount of use of the prosthesis, the use of any other prosthesis, and the demographic factors that might be related to use of the prosthesis. The average duration of follow-up was five years (range, twenty-five months to seventeen years). Forty of the forty-four patients also had a conventional prosthesis. Twenty-two patients (50 per cent) rejected the myoelectric prosthesis completely; thirteen (32 per cent) of the forty patients who also had a conventional prosthesis rejected the conventional prosthesis completely. The patients who used the myoelectric device the least were employed in occupations that required high-demand use of the prosthesis (lifting of more than 4.5 kilograms [ten pounds] or repetitive manual labor) or were receiving or seeking Workers' Compensation, or both.

Adolescent↗

PubMed1992

Intravenous regional bretylium and lidocaine for treatment of reflex sympathetic dystrophy: a randomized, double-blind study.

Patients with reflex sympathetic dystrophy, who received transient pain relief from stellate ganglion blocks or lumbar sympathetic blocks and had abnormal isolated cold stress tests, were enrolled in a study to determine the efficacy of intravenous regional bretylium. Each patient received two control treatments (0.5% lidocaine) and two treatments with 0.5% lidocaine and bretylium 1.5 mg/kg in a randomized, double-blind fashion. A standard intravenous regional technique was used with a 300-mm Hg tourniquet pressure for 20 min. Patients kept a daily record of pain relief (0 = no relief, 100% = complete relief). A decrease in pain of more than 30% was considered clinically significant. Therefore, once the patient's pain relief was less than 30%, the next intravenous regional treatment was performed. Bretylium and lidocaine provided more than 30% pain relief for a mean of 20.0 (+/- 17.5) days, whereas lidocaine alone provided relief for only 2.7 (+/- 3.7) days (Mann-Whitney U-test, P less than 0.001). A mean temperature increase in the treated limb of +2.64 +/- 3.41 degrees C above the baseline temperature was noted after bretylium administration, whereas after control treatments the change was -0.086 +/- 1.30 degrees C (Mann-Whitney U-test, P less than 0.02). We conclude that the combination of bretylium and lidocaine is significantly more effective than lidocaine alone when an intravenous block is used to treat reflex sympathetic dystrophy.

Autonomic Nerve Block↗

PubMed1991

Effects of venous hypertension on rabbit free flap survival.

A two-stage project was developed to study the effect of increased venous pressure on blood flow and survival in microvascular free tissue transfers. A rabbit epigastric fasciocutaneous free flap model was used. The blood flow in the rabbit epigastric free flap is 1.07 +/- 0.06 ml/min. The average venous pressure is 8.6 +/- 1.7 cm water. A logarithmic relationship between blood flow and venous pressure was demonstrated, with a statistically significant decrease in blood flow to 20-35% of the control values when the venous pressure rose above 28-30 cm water. This study stands in support of the tolerance by free tissue transfers of pressures below this range. The results further show a positive correlation between increasing venous pressure and free flap failure.

Animals↗

PubMed1990

Anterior sleeve fracture of the capitellum.

The case of an articular sleeve fracture of the capitellum in an 8-year-old girl is presented. An accurate diagnosis of this injury and its extent was able to be made preoperatively only by arthrography. The use of arthography in injuries about the elbow in children is recommended.

Arthrography↗

PubMed1989

Coverage problems of the foot and ankle.

Difficult wound coverage problems about the foot and ankle can occur secondary to trauma, osteomyelitis, foot deformities, tumors, or neuropathies (in particular, diabetes mellitus). Coverage can be difficult because of the special weight-bearing properties of the foot, the lack of intervening muscle between the skeletal elements and the integument, and the limited mobility of the overlying integument. Sorting out the 40 to 50 flap options for the foot and ankle requires a classification that describes the wound, the patient, and the available surgical options. The wound is classified based on size, anatomic location, and the presence or absence of infection. The anatomic location also describes the weight-bearing characteristics of the wound. Associated arterial, nerve and skeletal injuries are noted. A very small wound is less than 2 X 2 cm. A small wound is from 2 X 2 to 4 X 5 cm. A medium wound is from 4 X 5 to 7 X 7 cm. A large wound is from 7 X 7 to 10 X 20 cm, and a very large wound is from 10 X 20 up to 15 X 40 cm. Does the wound involve weight-bearing skin? Patient considerations include age and the presence of systemic or local compromise. Tobacco use, cosmetic concerns, occupation, rehabilitation potential, and amputee prejudices should be ascertained. Flap options can be classified as local transpositional, island pedicle, distant pedicle, and free-tissue transfers. The flaps may or may not incorporate muscle that may be needed for revascularization and dead space management in osteomyelitis. Some flaps are inappropriate because of local artery or nerve injuries. Some flaps will provide sensate coverage, and others can provide reinnervation potential. The potential to create new neuromas, ease of dissection, flap reliability, and cosmesis of the donor site are all important considerations.

Adult↗

PubMed1989

Accessory nerve palsy following thoracotomy.

A previously unreported cause of 11th cranial nerve palsy is described in a 53-year-old man. Dysfunction of the trapezius branch of the spinal accessory nerve occurred following median sternotomy and was documented by electromyography. This injury resulted in dysfunction of the trapezius muscle with loss of support of the shoulder girdle and pain. The injury may have been due to stretching from sternal retraction or injury secondary to internal jugular venous cannulation.

Accessory Nerve Injuries↗

PubMed1988

Neuropathic arthropathy of the shoulder. A case report.

A case of neuropathic arthropathy of the shoulder secondary to syringomyelia is presented. The classic clinical and radiographic features of the entity are illustrated. Emphasis is made on the use of magnetic resonance imaging in evaluation. Neuropathic arthropathy should be considered in the evaluation of shoulder pain or instability.

Adult↗

PubMed1988

Unrecognized pin penetration in slipped capital femoral epiphysis.

There are at least nine different techniques recommended to lower the incidence of femoral head penetration by fixation pins in the pinning of slipped capital femoral epiphyses. The routine use of fluoroscopy and placement of the fixation pins no closer than 8 mm (or one-third the radius of the femoral head) from the subchondral bone will leave a safe, workable margin. Confirmation of subchondral location after the procedure can be done with fluoroscopy. With the leg in maximal internal rotation, the fluoroscopic unit is rotated from anteroposterior (AP) to lateral under continuous monitoring to detect anterolateral and posteromedial quadrant penetrations. With the fluoroscopic unit in the lateral position, the foot is externally rotated 90 degrees, again under continuous monitoring, to visualize the anteromedial and posterolateral quadrants. If the femoral head cannot be well-visualized in the lateral view, use of a lateral x-ray machine and AP fluoroscopy can be helpful. Another useful technique when the head cannot be well-visualized is the injection of contrast medium through a cannulated screw.

Bone Nails↗

PubMed1985

Volar intercalated segment instability secondary to medial carpal ligamental laxity.

The midcarpal joint is stabilized by active, longitudinal compressive forces which produce balancing lateral volar flexion and medial dorsiflexion moments on the lunate. Laxity of the capitotriquetral ligament results in failure of the triquetral-hamate joint to produce a dorsiflexion moment, and the unbalanced volar flexion moment generated by the scaphoid produces volar intercalated segment instability (VISI). Four patients are reported to demonstrate the mechanics, clinical manifestations, and treatment of VISI.

Adolescent↗

PubMedDate not supplied

Injury patterns in recreational rock climbers.

We studied 39 recreational rock climbers to determine the incidence and pattern of injuries sustained in the sport at their level. Eleven climbers (26%), who climbed beyond the sport level, had sustained a major injury from a fall. Thirty-five climbers (89%) sustained at least one significant injury. Fifty percent of the injuries involved the hand or wrist. Only seven climbers (19%) had evidence of a digital pulley injury (climber's finger). Four climbers (11%) had evidence of a carpal tunnel syndrome. Twenty climbers (50%) had tendinitis in an upper extremity on physical examination.

Accidental Falls↗