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Biomedical subjects

J R Doyle

Publications and source records attributed to J R Doyle.

At least 19 recordsLinked to original sources
PubMed2001

Palmar and digital flexor tendon pulleys.

Retinacular structures, called pulleys, maintain the flexor tendons of the hand in constant relationship to the joint axes and promote economy and efficiency in finger flexion. This system is composed of the transverse carpal ligament, the palmar aponeurosis pulley, and the digital flexor pulley system. Of these three components, the digital pulleys are the most critical to finger flexion. In their normal state, these pulley components are ideal in all aspects including configuration and location, which accomodates a 260 degrees arc of motion without impingement and with minimum friction while at the same time using muscle tendon excursion that is well within the natural range of the muscle. An absent pulley results in an increased moment arm and requires increased tendon excursion to produce the same arc of motion. Because muscle excursion is not a limitless factor and is directly proportional to muscle fiber length, the effectiveness of tendon excursion is dependent on maintenance of the critical relationship between pulleys and the adjacent joints. Preservation and reconstruction of this system is based on knowledge of the anatomy and an understanding of the relative functional significance of each component of the system.

Biomechanical Phenomena↗
PubMed1998

Anatomy of the upper extremity muscle compartments.

Multiple and anatomically distinct compartments are present in the upper extremity. A compartment is defined as an enclosed space formed by fascia or by a combination of fascia and bone that contains one or more muscles. Knowledge of these anatomic compartments and their contents will facilitate early diagnosis and treatment.

Arm↗
PubMed1997

Prevalence of hereditary hemochromatosis in a Massachusetts corporation: is Celtic origin a risk factor?

The prevalence of homozygous hereditary hemochromatosis (HHC) is estimated at 1:250 in Caucasian adults. Little is known about ethnic subpopulations that might be at increased risk for this disease. HLA data have suggested a Celtic origin for HHC. Screening for HHC was offered to all employees of the Massachusetts Polaroid Corporation. Participants with a transferrin saturation of >55% or >45% and an elevated serum ferritin concentration on two screenings were referred for liver biopsy. The diagnosis of HHC was based on histological criteria, quantitative hepatic iron determination, hepatic iron index, and the phlebotomy requirement for iron depletion. Participants completed a questionnaire regarding their ethnic background. Two thousand two hundred ninety-four employees were screened, and 5 cases of HHC were detected. All 5 cases involved Caucasian men, yielding a prevalence of 1:395 for the Caucasian population. Four of the 5 cases were of 100% British-Irish ancestry based on the country of origin of their grandparents. Additional analysis revealed that the majority of grandparents of all 4 individuals came from Ireland or Wales. The exact two-tailed trend test showed a significant association of HHC with Celtic background (P = .012). The estimated cost of screening per patient identified was $18,041. Polaroid Corporation has a high representation of employees of British-Irish ancestry. Our data suggest that they are at high risk for developing HHC. A significant association of HHC with Celtic ancestry was found in this subpopulation, supporting the concept of a Celtic origin for this disease.

Adult↗
PubMed1994

Outcome following epineurotomy in carpal tunnel syndrome: a prospective, randomized clinical trial.

To assess the efficacy of an adjunctive epineurotomy in carpal tunnel syndrome, 36 wrists in 33 patients were prospectively randomized into epineurotomy and non-epineurotomy treatment groups. The operating surgeons and evaluating therapist were double-blinded. Patients were evaluated preoperatively and at either 6 or 12 months postoperatively, with 15 patients examined at both postoperative time points. Evaluation consisted of five sensory and four motor tests: static and moving two-point discrimination, Semmes-Weinstein monofilament testing, vibratory (30 and 256 cps) sensibility, and dynamometer testing of grip strength and lateral, three-jaw, and tip pinch strengths. Sensory testing showed overall improvement within both groups postoperatively, but there was no difference between the two groups at either 6 or 12 months postoperatively. Motor testing revealed no improvement in the grip strength or lateral, three-jaw, or tip pinch of either group at 12 months when compared to preoperative levels. Twenty-four of 26 epineurotomy patients and all 10 control patients were satisfied with their clinical outcome 30 months after surgery. The addition of an adjunctive epineurotomy, although safe, offered no clinical benefit in the surgical treatment of carpal tunnel syndrome in this series.

Carpal Tunnel Syndrome↗
PubMed1990

Anatomy and function of the palmar aponeurosis pulley.

The transverse fibers of the palmar aponeurosis are attached by vertical septa to the underlying transverse metacarpal ligament and thus form a pulley over the flexor tendons. It is a constant and substantial retinacular structure that overlays the synovial sheath. Because of its proven function, position and breaking strength, I believe it should be considered part of the flexor tendon pulley system.

Fascia↗
PubMed1990

Detectionless processing with semantic activation? A footnote to Greenwald, Klinger, and Liu (1989)

Recently published research has suggested that, in a pattern masking task, semantic activation caused by the target may continue to exist even though subjects cannot detect the target. The experiments are reassessed as an exceptional case of the more general rule that subjects are able to use residual semantic activation to actually detect targets. Furthermore, residual graphic information is far less effective at supporting near-chance target detections.

Arousal↗
PubMed1989

Rupture of the radial collateral ligament of the metacarpo-phalangeal joint of the index finger: a report of three cases.

We have diagnosed and treated three patients with complete rupture of the radial collateral ligament of the metacarpo-phalangeal joint of the index finger. Rupture of the radial collateral ligament of the metacarpo-phalangeal joint occurs most commonly in the little finger and has not previously been reported in the index finger. Operative treatment is recommended in all cases, due to the significant stresses placed on the radial side of the M.P. joint of the index finger.

Adult↗
PubMed1989

Anatomy of the flexor tendon sheath and pulley system: a current review.

The flexor tendon sheath in the fingers is a synovial-lined, fibroosseous tunnel with segmental condensations of fibrous tissue. These fibrous bands or pulleys are: (1) the palmar aponeurosis pulley (formed by the transverse fibers of the palmar aponeurosis), (2) five annular pulleys, and (3) three cruciform pulleys. The second and fourth annular pulleys are the largest, thickest, and most constant in form and incidence. The first, third, and fifth annular pulleys are less constant in shape and incidence as are the cruciform pulleys. No other pulleys have been identified in this study.

Biomechanical Phenomena↗
PubMed1989

A mechanical study of six digital pulley reconstruction techniques: Part I. Mechanical effectiveness.

A laboratory study on fresh-frozen human cadaver limbs compared six types of flexor tendon pulley reconstruction in the fingers. The reconstructions used were those described by (1) Bunnell, (2) Karev, (3) Weilby, and (4) Lister, and two types developed by us that have not been previously described. The pulleys were studied in specific configurations to determine their effectiveness in transforming tendon excursion into finger flexion. In each finger, comparison was made between the amount of tendon excursion required for full flexion with an intact pulley system versus the various types of reconstructed pulleys. The ratio of these two values was defined as the mechanical effectiveness of the pulley reconstruction. The Karve reconstruction was most effective at 108.2%, which was significantly different from the other five reconstructions (p less than 0.01). The remaining reconstructions ranged in effectiveness from 80.0% to 88.5%.

Aged↗
PubMed1989

A mechanical study of six digital pulley reconstruction techniques: Part II. Strength of individual reconstructions.

A laboratory study was done on fresh-frozen human cadaver limbs, using six types of pulley reconstructions about the flexor tendons of the fingers. The reconstructions used were those described by (1) Bunnell, (2) Karev, (3) Weilby, and (4) Lister, and two types developed by us that have not been previously described. The pulleys were tested at constant strain rate to failure with the peak force recorded as the breaking strength. A total of 385 reconstructed pulleys were tested and the results were analyzed statistically. A new "loop and one half" pulley reconstruction was significantly stronger than the other five reconstructions (p less than 0.01) with an average load to failure of 22.5 kilograms-force. The other pulley reconstructions varied in average breaking strength from 2.8 kilograms-force to 18.4 kilograms-force.

Biomechanical Phenomena↗
PubMed1989

Congenital anomalies of the upper extremity.

This article has reviewed some of the current methods of management of congenital problems in the upper extremity. Not all problems have been included in this review but some of the landmark advances in this field have been considered. The management of congenital anomalies may change significantly in the future.

Arm↗
PubMed1989

Replantation.

Replantation is firmly established as a viable treatment option in many accidental amputations involving the upper extremity. The clinical foundation was laid more than 100 years ago and it is a technique which is now available world wide. The success rate of replantation exceeds 80 per cent. More often than not, appropriately selected patients obtain a functional result which is better than currently available prosthetic devices. The experience gained from small vessel surgery in replantations has aided in the development of reconstructive procedures, including free composite tissue transfers such as toe-to-hand transfers and free flaps.

Amputation, Traumatic↗
PubMed1989

Nerve suture and grafting.

Nerve anatomy, terminology, and techniques for nerve restoration are reviewed in sufficient detail to allow the reader to quickly update his or her knowledge in this area. Ideas for future directions of study are presented.

Hand↗
PubMed1988

Tendon xanthoma: a physical manifestation of hyperlipidemia.

Tendon xanthoma, a nonneoplastic tumor of tendon is a significant physical manifestation of hyperlipidemia. These lesions may accompany rapidly progressive atherosclerosis and may signal the presence of life threatening hyperlipidemia. We have seen three patients with tendon xanthoma, and one patient was treated by surgical excision of large xanthomas arising from the substance of the extensor tendons over the metacarpophalangeal (MP) joints of the hand. Because these lesions arise from the substance of the extensor tendons complete removal may result in loss of tendon continuity and function. Surgery in the form of subtotal excision is advised for functional or cosmetic reasons. Although incomplete removal may be associated with recurrence, appropriate medical management may prevent or delay this recurrence.

Aged↗
PubMed1988

Anatomy of the finger flexor tendon sheath and pulley system.

Additions and changes in the description of the anatomy of the finger flexor sheath and pulleys that I published in 1974 and 1975 have prompted me to restudy this system. Sixty-one fresh human cadaver fingers were dissected using the operating room microscope. This study demonstrated a flexor synovial sheath composed of visceral and parietal elements from the neck of the metacarpal to the distal interphalangeal joint, which was overlaid with a series of retinacular structures (pulleys). The pulleys identified were the palmar aponeurosis pulley, five annular pulleys, and three cruciform pulleys. Although significant variations were noted in the morphology of the first annular and the cruciform pulleys sufficient similarity exists between my first description and the present study to support the use of the original descriptive terminology. A significant addition to the pulley system is the palmar aponeurosis pulley described by Manske and Lesker.

Finger Joint↗