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T R Light

Publications and source records attributed to T R Light.

At least 55 records · Page 3Linked to original sources
PubMed1982

Relationship of 99mTc-MDP uptake to regional osseous circulation in skeletally immature and mature dogs.

Uptake of intravenously injected 99mTc-MDP in multiple regions of healthy skeletally immature and mature dogs was correlated with regional chondro-osseous blood flow determined by radioactively labeled microspheres. Compared to the microsphere distribution, the distribution of 99mTc-MDP indicated that blood flow is an important, but not exclusive, factor in the uptake of bone-seeking tracers. Other factors such as the affinity of the tracer for the various types of chondro-osseous tissues must also affect tracer uptake. A measure of the relative affinity of 99mTc-MDP for bone was derived by the ratio of the percentage of tracer uptake to the percentage of blood flow. The juxta-ephyseal region demonstrated the greatest affinity for the tracer, followed in decreasing affinity, by the cortical bone, epiphyseal cartilage, trabecular bone of the metaphysis and secondary ossification center, and marrow space. Within the spongiosa, affinity generally increased as the proportion of osseous trabeculae relative to marrow space increased. 99mTc-MDP uptake is disproportionately increased in areas of active bone growth and remodeling where the surface area of hydroxyapatite crystals available for adsorption is probably highest.

Animals↗
PubMed1982

Hands on stamps.

Explore the source record for details and available documents.

Anatomy↗
PubMed1982

Quantitation of regional chondro-osseous circulation in canine tibia and femur.

Regional osseous blood flow (OBF) to various regions of the femur and tibia was measured using radioactively labeled 15-micrometers microspheres injected into the right atrium of neonatal, skeletally immature, and skeletally mature canines. Each bone was divided into as many as 41 anatomically distinct sections to assess developmental and regional comparisons in OBF. A quantitative decrease in OBF with increasing chondro-osseous maturity was observed for both the whole bones as well as many regions within a given bone. This was particularly significant in the tibia in which OBF to the mature tibia was much lower than in the immature tibia or even the mature femur. In the immature and neonatal bones, the epiphyseal and metaphyseal regions nearest the physes had the highest flow. The physis had a statistically significant high flow rate. Furthermore, regional differences in OBF correlated well with known regional functions in both endochondral and membranous (periosteal) bone formation. OBF tended to be greater in regions of greater metabolic activity associated with hematopoiesis and endochondral osteogenesis. OBF values correlated well with regional predilections of various diseases such as acute hematogenous osteomyelitis prior to skeletal maturity and osseous metastases, and, by extrapolation, strongly support a physiological reason for delayed healing and nonunion in tibial fractures in the skeletally mature human.

Aging↗
PubMed1982

Metastatic tumors of the foot: case report and literature review.

Metastatic lesions to the bones of the foot occurred in three elderly patients. Biopsy established the diagnosis in a 90-year-old woman. In a 72-year-old man and a 79-year-old man, the diagnosis was possible from roentgenographic features. In the latter, biopsy of an additional osseous metastatic site established the diagnosis. A thorough review of the literature has yielded 72 previously reported cases of metastasis to the foot. Only 38 of these cases were histologically confirmed. Primary tumors of the colon, kidney, and lung are the most common sources of metastasis to the bones of the foot. Metastatic disease should be considered in elderly patients presenting with foot pain and osteolytic lesions, especially when there is a history of a previously diagnosed malignancy. The generally poor prognosis indicates that treatment should be clearly designed to relieve pain.

Adenocarcinoma↗
PubMed1981

Radiology of postnatal skeletal development. IV. Distal radius and ulna.

Thirty-one pairs of distal radioulnar units were obtained from human cadavers ranging in age from full-term neonates to fourteen years. These were studied morphologically and radiographically. Specimen roentgenography using air/cartilage interfacing demonstrated the osseous and cartilaginous portions of the epiphyses. These roentgenographic aspects of development are discussed and illustrated to provide a reference index. The radial and ulnar physeal/metaphyseal contours initially are transverse. Progressively the distal radius develops a proximally directed curve adjacent to the radioulnar joint. Both physes subsequently develop a convex contour with mild undulations, and a central concavity associated with the secondary ossification center. Longitudinal ossification striations were observed crossing the distal ulnar physis. These appear to be normal. At no time during postnatal development did the distal ulna ever articulate directly with the carpus. It was always separated by a segment of triangular fibrocartilage connecting the ulnar styloid to the distal radial epiphysis. This was never perforated. This discoid cartilaginous structure is the anatomic cause of the concomitancy of ulnar styloid fractures with distal radial epiphyseal injuries, an injury pattern which may occur prior to ossification in the ulnar styloid, and which may lead to non-union of the styloid when ossification eventually occurs. In none of the specimens was an accessory ossification center present in either the radial or ulnar styloid process.

Adolescent↗
PubMed1981

Correlative roentgenography and morphology of the longitudinal epiphyseal bracket.

Detailed examination of a complete chondro-osseous specimen from a patient with duplication of the first ray of the foot revealed the involved metatarsal had a trapezoid-shaped, diaphyseal-metaphyseal osseous unit that was longitudinally bracketed along the lateral side by a functioning physis, epiphysis, and secondary (epiphyseal) ossification center. The physis extended as an arc from the medial proximal side toward and along the lateral side and then back to the medial side distally. The medial side of the diaphysis had a normal periosteum. The longitudinal epiphyseal ossification bracket was a composite of initially separate proximal and distal secondary ossification centers that had progressively extended toward each other and finally coalesced along the laterally placed epiphyseal cartilage. We have termed this deformity the "longitudinal epiphyseal bracket" (LEB). The macroscopic and microscopic anatomy relevant to initial diagnosis and evaluation of sequential roentgenographic changes will be considered.

Bone Diseases, Developmental↗
PubMed1981

The longitudinal epiphyseal bracket: implications for surgical correction.

Surgical approaches to the correction of deformities in the skeletally immature hand or foot require adequate comprehension of the specific and changing chondro-osseous anatomy of each lesion. Detailed macroscopic and microscopic examination of an abnormal metatarsal showed a trapezoid-shaped diaphyseal/metaphyseal osseous unit that was longitudinally bracketed by a functioning physis and epiphysis along the lateral side. Only the medial side of the diaphysis had a normal periosteum. The arcuate physis extended from the medial, proximal side toward and along the lateral side and then back to the medial side distally. The epiphyseal ossification center was a composite of initially separate proximal and distal secondary centers that had a extended toward each other within the laterally placed epiphyseal cartilage. We have termed this deformity a "longitudinal epiphyseal bracket." We suggest that in the skeletally immature patient, opening wedge chondro-osteotomy should not routinely be accompanied by interposed bone graft extending to either the split ossification center or the physeal cartilage. Such a procedure may induce a partial surgical epiphyseodesis with subsequent progressive recurrence of the angular deformity or cessation of longitudinal growth. Instead, based on our anatomical findings, and preliminary surgical cases, we recommend osteotomy accompanied by fat interposition comparable to the Langenskiöld procedure for traumatic epiphyseodesis.

Bone Diseases, Developmental↗
PubMed1981

Pathobiology of septic arthritis and contiguous osteomyelitis in a leatherback turtle (Dermochelys coriacea).

Analysis of a case of presumed hematogenous septic arthritis and osteomyelitis involving the elbow, distal humerus, and proximal radius and ulna in a leatherback turtle (Dermochelys coriacea) showed the chondro-osseous response to be similar to the diseases in skeletally immature humans and terrestrial mammals (both spontaneous and experimental). This particular reptile has bone that is similar to mammalian bone. The infection had partially destroyed the distal humeral, proximal ulnar and proximal radial joint surfaces and epiphyseal cartilages. The elbow was filled with a fibrovascular pannus that had caused a partial ankylosis of the joint.

Animals↗
PubMed1981

Hands on stamps.

Explore the source record for details and available documents.

Anatomy↗
PubMed1980

Diagnosis and management of fractures in the multiply injured patient.

Careful and frequent examination of the patient is critical to the success of treating the multiply injured patient. Many "occult" fractures are often missed initially because attention is focused on major, life-threatening injuries. It is essential that the various specialists treating the multiply injured patient communicate effectively among one another regarding priorities and proposed therapies. If one service anticipates operative management of a specific injury, it may be coordinated with orthopedic needs, fracture fixation, or reduction being carried out simultaneously. No patient should have orthopedic problems managed by benign neglect, even if the probability of survival is low. Many tragically injured patients do not survive the initial hours following an accident because of massive abdominal or intrathoracic injury. However, orthopedic management in all patients should be based on the assumption that the individual will survive. Maximum functional recovery should be expected in those who do survive, and thus necessitates careful planning of fracture treatment acutely and chronically.

Blood Vessels↗
PubMed1980

Anterior approach to hip arthroplasty.

Direct anterior approach to the hip joint utilizing a curved transverse skin incision and splitting the tensor fascia muscle longitudinally provides an effective exposure for carrying out primary total hip arthroplasty. Excellent visualization of the acetabulum is afforded by this direct approach. Modified femoral rasps of varying lengths are employed to rasp the femur with the leg in external rotation. Trochanteric osteotomy was carried out on only three occasions in a series of 104 procedures performed on 85 patients during a three-year period. The duration of operation averaged 65 minutes. Average blood replacement was 1.9 units in unilateral hips and 3.5 units in patients operated upon sequentially. Mean postoperative stay was 12.8 days following unilateral and 22.3 days following bilateral surgery. Four patients experienced perioperative complications. The anterior approach provides a safe and effective approach to total hip arthroplasty with limited morbidity.

Adolescent↗
PubMedDate not supplied

Correction of spinal instability and recovery of neurologic loss following cervical vertebral body replacement. A case report.

While replacement of cervical vertebral bodies may be required when they are compromised by infection, tumor, or injury, or when they impinge on the neural elements, this procedure does not add immediate stability and may cause additional problems. In this case, displacement of a large fibular graft into the spinal canal appeared to cause additional spinal cord and nerve root injury. Despite a long delay, decompression and firmly fitted and wired anterior and posterior grafts seemed to enhance the neurologic recovery and permitted rapid mobilization. The diagnostic value of computerized tomography is also demonstrated.

Adolescent↗
PubMedDate not supplied

Complex dislocation of the index metacarpophalangeal joint in children.

Four cases of complex dislocation of the index metacarpophalangeal joint prior to skeletal maturity were reviewed. Despite the generalized laxity present in these children, none of the dislocations could be anatomically reduced by closed methods. Two patients had a concomitant osteochondral fracture from the ulnar side of the metacarpal epiphysis; one subsequently developed a lesion similar to an epiphyseal osteochondroma. One patient developed ischemic necrosis leading to premature growth arrest; a shortened metacarpal, and a deformed metacarpal head. The possibility of vascular damage must be considered in the skeletally immature patient, since the epiphyseal and physeal circulation may be compromised by either the dislocation or exposure for the reduction.

Accidental Falls↗
PubMedDate not supplied

Postnatal growth and development of the flexor tendon pulley system.

The number, type, position, and size of the pulleys of the flexor tendon sheath of preserved cadaver hands from children ranging in age from newborn to 15 years were studied by dissection, observation, direct measurement, and radiographic evaluation. These studies delineated flexor tendon pulley development and their locations in the developing hand. Pulley positions are relatively constant throughout postnatal development, with the gross anatomic characteristics correlating closely to those of the adult hand. Mild abnormalities in the location of pulleys were identified in three hands classified as growth-retarded on the basis of an inconsistency between skeletal and chronologic ages. The flexor tendon system of the skeletally immature hand progressively develops in concert with adjacent chondro-osseous and soft tissue elements.

Adolescent↗