Search PubMed⌕ Search

Biomedical subjects

P M Weeks

Publications and source records attributed to P M Weeks.

At least 37 records · Page 2Linked to original sources
PubMed1989

Management of synovial sarcoma of the median nerve at the elbow.

Synovial sarcoma is a high-grade malignancy with a marked propensity for local recurrence and a moderate rate of regional lymph node involvement. It usually causes death from massive pulmonary metastases. Despite its aggressive biologic behavior, en bloc wide local resection of small extremity tumors rather than amputation may be indicated if removal of all gross disease is possible. Extremity morbidity from resection of vessels, nerves, and soft-tissue bulk can be minimized by the use of composite reconstruction techniques currently available. A case report is presented to illustrate aggressive limb-sparing surgical therapy of a small, favorably located synovial sarcoma with immediate neurovascular and soft-tissue reconstruction. The literature is reviewed to aid subsequent surgeons faced with management of this uncommon tumor.

Abdominal Muscles↗
PubMed1989

Identification of the collagen-producing cells in healing flexor tendons.

A monoclonal antibody to procollagen type I (anti-pC) which specifically stains cells synthesizing collagen was used to study the healing of chicken flexor tendons in vivo. Healing was assessed using routine hematoxylin and eosin histology and immunoperoxidase staining with anti-pC. Studies showed that epitenon cells proliferate 3 days after injury and are producing collagen by 7 days after injury. Tenocytes do not begin producing collagen until 14 to 21 days after injury. From 3 to 5 weeks, the entire substance of the tendon becomes filled with collagen-synthesizing cells. These cells may have originated from the tendon sheath, the epitenon, or the endotenon; however, the evidence presented in this study suggests that the epitenon is a major source of these cells.

Animals↗
PubMed1988

Role of radionuclide imaging in the evaluation of wrist pain.

The cause of hand and wrist pain can be difficult to determine, especially when standard radiographs are normal or show only nonspecific changes. This study reports the effectiveness of radionuclide imaging in the evaluation of patients with hand and wrist pain of uncertain cause. Eighty-eight patients with hand and wrist pain and initially normal standard radiographs were evaluated prospectively by additional radiographic methods including the following: routine tomography, wrist arthrography, computerized tomography, or magnetic resonance imaging. Each patient also had bone scintigraphy. The diagnosis established by clinical assessment and by other imaging methods was then compared with the scintigraphic findings. The presence or absence of focal scintigraphic abnormalities correlated with the presence or absence of focal pathology definable by the conventional methods in 88% of patients. As expected, scintigraphy was chiefly of value in defining the locus of an injury or other process in the wrist, rather than the nature of an abnormality. The scintigrams were abnormal in 95% of cases involving complete intrinsic ligament ruptures and fractures and were normal in 96% of patients with no definable injury. Scintigraphic findings correlated poorly with partial intrinsic ligament injuries and in cases of synovitis. Radionuclide imaging is a sensitive means of detecting focal lesions in patients with hand and wrist pain of unknown cause.

Adult↗
PubMed1988

Arthrographic surface anatomy of the carpal triangular fibrocartilage complex.

In a review of 364 radiocarpal and 123 distal radioulnar joint arthrograms we identified 44 (12%) patients with contrast defects at either the proximal or distal surface of the carpal triangular fibrocartilage complex (TFCC). Differences in their arthrographic characteristics distinguished two separate groups of patients; one with similar and another with dissimilar appearing TFCC surface contrast collections. Thirty-one of our 44 patients had similar appearing, isolated radial-sided collections at either the proximal or distal TFCC surfaces. Our arthrographic, demographic, and historical study of these patients suggests that the collections are not caused by traumatic partial TFCC tears but represent a normal anatomic variant, probably a synovial recess at the radial TFCC attachment. Arthrography and dissection of a limited number of cadaveric specimens confirmed this conclusion. The second group included the remaining 13 patients. This group had contrast collections at either the proximal or distal TFCC surface, which varied in location and appearance. This smaller group is more likely to represent those uncommon patients with partial TFCC defects caused by tears.

Adolescent↗
PubMed1988

Multiple nerve dysfunction after carpal tunnel release.

A case is reported of the delayed onset of multiple nerve dysfunction after simple carpal tunnel release. The patient received a local anesthetic with the use of an arm tourniquet. The multiple dysfunctions included radial sensory and motor dysfunction at 5 days, anterior interosseous nerve syndrome at 33 days, and ulna intrinsic motor loss between 33 and 77 days after operation. There was no recovery in the radial or anterior interosseous nerves after 5 months of conservative management. At operation the radial nerve was compressed by the intermuscular septum, and the anterior interosseous nerve was compressed by the superficialis arcade. Decompression was followed by complete recovery.

Adult↗
PubMed1988

Fracture of the dorsoulnar tubercle of the trapezium.

The dorsoulnar tubercle of the trapezium may fracture, and this fracture may be missed without precise physical examination and correct radiographic studies. If there is persistent localized pain and tenderness in this region and the results of routine wrist radiographic examination are normal, a bone scan should be performed. If there is localized uptake in the area of the trapezium, additional radiographic studies may be necessary to confirm or exclude this fracture. Four patients with this previously unreported fracture and a method for its detection are presented.

Adult↗
PubMed1988

Autonomous healing of chicken flexor tendons in vitro.

A monoclonal antibody to procollagen type I, which specifically stains cells actively secreting collagen, was used to study the healing of chicken flexor tendons in vitro. Healing was assessed with histology, immunohistologic staining, and autoradiography. Studies showed that epitenon cells proliferate 2 days after injury and are producing collagen 4 days after injury. Endotenocytes remain dormant during this time period. Tendons in vitro demonstrate active collagen synthesis and thus the capacity for autonomous repair.

Animals↗
PubMed1988

Digital ischemia of the upper extremity: a systematic approach for evaluation and treatment.

Symptomatic upper extremity digital ischemia is an uncommon disorder reflecting diverse etiologies. Herein we present an algorithm to aid in evaluation and treatment of digital ischemia. This approach seeks to establish the diagnosis and lead to appropriate treatment while minimizing testing and therapy. Practical application of the algorithm is demonstrated through illustrative cases.

Adult↗
PubMed1987

Characteristics and management of flexor tendon graft disruption.

In order to define the proper management of patients with disruption of a flexor tendon graft, 220 consecutive flexor tendon grafts were reviewed. Patients were divided into two groups--those who did not require a silastic rod prior to tendon grafting (89 grafts) and those who did require a silastic rod prior to tendon grafting (131 grafts). The incidence of tendon graft disruption for these two groups was 1.1% and 7.6%, respectively. Based on an analysis of these 11 graft disruptions, a method of management was devised. The literature is reviewed regarding the incidence and method of management of disrupted flexor tendon grafts.

Adolescent↗
PubMed1986

Carpal avascular necrosis: MR imaging.

The authors evaluated the use of magnetic resonance (MR) imaging in diagnosis of avascular necrosis (AVN) of carpal bones by examining 21 patients with wrist pain and two healthy volunteers. MR images were compared with conventional radiographs in every case and with bone scintigrams in 18 cases. MR imaging was slightly less sensitive than bone scintigraphy in depicting AVN, but in patients who were imaged with long repetition time (TR)/long echo time (TE) sequences in addition to short TR/short TE sequences, MR imaging was found to be more specific. While the authors believe that bone scintigraphy remains the screening test of choice for patients with wrist pain and normal plain radiographs, MR imaging promises to add significant diagnostic information in cases in which bone scans are abnormal.

Adult↗
PubMed1986

Three-dimensional wrist imaging: evaluation of functional and pathologic anatomy by computer.

The wrist has been studied morphologically and functionally using advanced technology. The osseous morphology of the wrist was investigated by computed tomography and surface reconstruction software. The functional behavior of the wrist in motion was studied using electromagnetic tracker technology. Three-dimensional imaging from CT scans is emerging as a research tool for the study of gross surface morphology, especially for osseous structures. One of the most demanding applications of this technology lies in the human wrist, because of its small size and inherent complexity. We have demonstrated some of the potential of computer graphics and three-dimensional surface reconstructions in the wrist for patients with osseous abnormalities. Acquisition of six-degree-of-freedom kinematic data to describe carpal motion has been made possible by new electromagnetic tracker technology. Analysis of these data in human wrist experiments revealed that the instantaneous center of rotation was not fixed in the head of the capitate, as was previously thought.

Adult↗
PubMed1985

Disseminated histoplasmosis presenting as an acute tenosynovitis.

Disseminated histoplasmosis is usually a multifocal process with a wide variety of clinical presentations. Despite frequent bone marrow involvement, overt bone and joint disease is uncommon and isolated synovial involvement is extremely rare. We describe in this report an unusual case of disseminated histoplasmosis presenting as acute tenosynovitis. To our knowledge, this is only the second reported case of synovial involvement by H. capsulatum without a concomitant osseous lesion.

Acute Disease↗
PubMed1985

Three-dimensional imaging of the wrist.

The objective of this study was to determine the diagnostic quality of three-dimensional images of the carpal bones that could be constructed from raw data obtained from a computerized tomography scan. The quality of raw data collected was determined by collimation, slice interval, the number of projections, and x-ray tube operating specifications. The quality of two-dimensional images that were constructed from the raw data was determined by user-specified parameters including zoom or magnification factor, convolution kernels, and centering. The two-dimensional images were modified by erasure, the level of reconstruction, and animation, which permitted isolation of individual carpal bones, the construction of three-dimensional images viewing the external and internal surfaces of the bones, and the rotation of the images to provide multiple views. Representative images are presented.

Carpal Bones↗
PubMed1985

Comparison of early passive motion and immobilization after flexor tendon repairs.

Thirty-one flexor tendon repairs in 30 patients managed by early passive motion were retrospectively compared with 31 flexor tendon repairs in 30 patients managed by 3 weeks of postoperative immobilization. Repairs were performed by several surgeons, including plastic surgical residents. There were no statistically significant differences between the two groups comparing age, zone of injury, number of tendons repaired, nature of injury, or associated injuries. No statistically significant difference was found between the two groups when total active and total passive range of motion were compared for repairs in zone I, zone II, zones III and IV, and all zones combined. In the early passive motion group in zone II, there were 12 percent excellent results, 15 percent good results, 23 percent fair results, and 50 percent poor results. In the immobilization group, there were 18 percent excellent results, 8 percent good results, 23 percent fair results, and 53 percent poor results. There was no significant difference between the two groups (p less than 0.05).

Finger Joint↗
PubMed1985

When should nerve gaps be grafted? An experimental study in rats.

In conclusion, animal experiments have shown the following: (1) extensive elevation (mobilization) of a nerve from its bed does not interfere with its capacity to regenerate as long as the longitudinal epineural vessels are preserved, (2) suturing nerve ends under tension has a deleterious effect on the final results, (3) when a segment of nerve has been resected, the remaining nerve and the site of repair can lengthen to accommodate joint extension (within limitations), (4) if there is a segmental loss of nerve and if the nerve ends can be approximated with 10-0 epineural sutures, even if the joints must be fully flexed, the result is better than using a nerve graft, and (5) when a graft is required, it is important to avoid reversing the nerve graft. We believe direct nerve repair is preferred when flexion of the joints and mobilization of the nerve ends permits approximation with 10-0 epineural suture.

Animals↗
PubMed1985

The carpal boss: an overview of radiographic evaluation.

The carpal boss, an unmovable bony protuberance, is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This bony prominence may represent degenerative osteophyte formation and/or the presence of an os styloideum, an accessory ossification center that occurs during embryonic development. When this condition is symptomatic, patients present with complaints of pain and limitation of motion of the affected hand. The symptoms of carpal boss may result from an overlying ganglion or bursitis, an exterior tendon slipping over this bony prominence, or from osteoarthritic changes at this site. Radiographically, the view that best profiles the separate os styloideum is a lateral view utilizing 30 degrees of supination and ulnar deviation of the wrist. Once a diagnosis has been made, treatment can range from the use of nonsteroidal antiinflammatory medication and limited use of the wrist to surgical excision of the anatomic abnormality.

Bone Diseases↗
PubMed1985

Musculoskeletal applications of three-dimensional surface reconstructions.

We have applied computer programs originally developed for craniofacial surgical planning and evaluation to complex musculoskeletal problems. These computer programs reformat ordinary CT scans into black and white images of the three-dimensional osseous surfaces found in the scanned volume. These reformatted three-dimensional CT scan images increase the utility of CT scan examinations of complex osseous structures, such as the wrist, spine, hip, knee, and shoulder. The software, which operates on an unmodified commercially available CT scanner, can produce high-quality surface reconstructions from CT scan slices without operator intervention. No special knowledge of the principles used in the reconstruction methods is needed to successfully use the programs.

Adolescent↗