Biomedical subjects

Peter M Murray

Publications and source records attributed to Peter M Murray.

12 recordsLinked to original sources

PubMed2006

Prosthetic replacement of the proximal interphalangeal joint.

The first proximal interphalangeal joint (PIPJ) replacements were hinged devices allow-ing only single-axis motion. Newer implant arthroplasties of the PIPJ have anatomically designed proximal phalangeal and middle phalangeal components. Constrained devices have typically lead to failure at the hinge mechanism or the prosthetic bone interface. A need to create balanced forces across the joint was the rationale behind the semicon-strained PIPJ prosthesis, which uses an anatomic design. Limitations of the silicone PIPJ implant include its lack of resistance to valgus loading at the index and long digits during the pinch maneuver. It is generally believed that a PIPJ surface replacement arthro-plasty that preserves the collateral ligaments will achieve greater PIPJ stability.

Arthroplasty, Replacement↗

PubMed2005

Radioscapholunate arthrodesis.

Although RSL fusion is a viable option for isolated radiocarpal arthritis, the enthusiasm for this procedure should be tempered with the reality that kinematics of the wrist is not entirely suited for independent midcarpal flexion and extension [10]. Limited wrist flexion and extension is expected following a successful RSL arthrodesis. The effects of imposed abnormal kinematics are further shown by the high incidence of RSL nonunions, occurrence of scaphoid fractures, and postoperative deterioration of the midcarpal joint [15,22]. In a young patient with posttraumatic arthritis or rheumatoid arthritis limited to the radiocarpal joint, however, RSL arthrodesis remains a viable alternative to complete wrist arthrodesis if the midcarpal joint is normal. Internal fixation with plates and screws and distal scaphoid excision are technical alternatives to consider when an RSL arthrodesis is performed.

Arthritis↗

PubMed2005

Diagnosis and treatment of longitudinal instability of the forearm.

Radio-ulnar dissociation can result from high-injury trauma that the compressive forces traverse the wrist forearm and elbow. This injury can be thought of as an "unhappy triad" of radial head fracture, triangular fibrocartilage complex failure, and a tear of the interosseous membrane. The radius is the primary stabilizer of the forearm with the forearm interosseous membrane enabling load sharing between the radius and the ulna. The central one-third of the interosseous membrane is 3 times stronger than the membranous portion and approaches the strength of the anterior cruciate ligament for determining interosseous membrane injury. Imaging studies with proven diagnostic efficacy include magnetic resonance imaging and ultrasound. Surgical treatment should be considered when circumstances imply longitudinal instability of the forearm. Surgical treatment includes open reduction/internal fixation or prosthetic replacement of the radial head as well as repair of the disrupted triangular fibrocartilage complex. Successful treatment of radioulnar dissociation is predicated on early diagnosis of the condition.

Biomechanical Phenomena↗

PubMed2004

Free vascularized bone transfer in limb salvage surgery of the upper extremity.

Salvage of the upper extremity following tumor resection may require reconstruction of massive bone defects. This more commonly results from malignant bone tumors, but defects requiring reconstruction also may occur following resection of locally aggressive benign tumors. Examples include osteosarcoma, chondrosarcoma, Ewing sarcoma, giant cell tumor, and certain soft tissue sarcomas invading bone. Obtaining satisfactory results using conventional bone grafting techniques is at best challenging when defects of substantial size are encountered. Free vascularized bone grafting procedures provide the appealing option of transferring living bone based on a vascular pedicle.

Animals↗

PubMed2004

Soft tissue sarcoma of the upper extremity.

Soft tissue sarcomas of the upper extremities are rare and hand surgeons typically encounter only one or two undiagnosed soft tissue sarcomas during their careers. It is incumbent on the physician to review repeatedly the characteristics of these tumors and remain suspicious, because these lesions typically are misdiagnosed and treatment is delayed. The most common soft tissue sarcomas of the upper extremity are the epithelioid sarcoma, synovial cell sarcoma, and malignant fibrous histiocytoma. Limb salvage surgery is the treatment of choice for soft tissue sarcomas to preserve upper extremity function. Following wide tumor resection, adjuvant therapies such as chemotherapy, external beam radiation therapy, and brachytherapy may lessen local recurrence rates, but their effect on overall survival remains unclear.

Arm↗

PubMed2004

Malignant fibrous histiocytoma of the distal radius: a case report.

We report a case of a primary malignant fibrous histiocytoma of the distal radius in a 46-year-old man. Treatment involved en bloc resection, reconstruction with a nonvascularized free fibular autograft, and wrist arthrodesis combined with adjuvant chemotherapy. At the 2-year follow-up evaluation the patient had a satisfactory outcome with complete radiographic union and no evidence of a local recurrence or metastasis. Resection combined with autogenous fibular grafting and adjuvant chemotherapy appears to be an acceptable method for treating malignant fibrous histiocytoma of the distal radius in this patient.

Bone Neoplasms↗

PubMed2004

Palmar fasciitis and arthritis syndrome associated with metastatic ovarian carcinoma: a report of four cases.

Palmar fasciitis and polyarthritis syndrome (PFPAS) is an uncommon paraneoplastic syndrome associated with several malignant neoplasms. We identified 4 patients with PFPAS and ovarian carcinoma. Palmar fasciitis, at times severe, and inflammatory polyarthritis dominated the clinical presentation in all 4 patients. In 3 of our 4 patients the presentation of palmar fasciitis and inflammatory polyarthritis preceded the diagnosis of ovarian carcinoma. Magnetic resonance scanning and biopsy examination of palmar nodules in one patient revealed findings of inflammation and fibrosis. A literature review found 10 other cases of PFPAS associated with ovarian carcinoma. Improvement in palmar fasciitis and inflammatory arthritis often occurs after successful treatment of the ovarian carcinoma. Digital contractures, however, can persist. We recommend a gynecologic examination in any woman presenting with the sudden onset of unexplained hand pain, palmar inflammatory fasciitis, palmar fibromatosis, and digital contractures.

Aged↗

PubMed2002

The efficacy of magnetic resonance imaging and ultrasound in detecting disruptions of the forearm interosseous membrane: a cadaver study.

The purpose of this study was to examine the efficacy of magnetic resonance imaging (MRI) and ultrasound (US) in determining complete disruptions of the central portion of the forearm interosseous membrane. The midportion of the forearm interosseous ligament was longitudinally incised in 19 fresh-frozen cadaver arms. The specimens were imaged with MRI and US. The MRIs were examined by a hand surgeon, a musculoskeletal radiologist, and a general radiologist, all blinded to the state of the interosseous membrane. The musculoskeletal radiologist and general radiologists read the real-time US images in a consensus fashion. Magnetic resonance imaging showed a 96% accuracy rate, a 100% positive predictive value, a 93% negative predictive value, 93% sensitivity, and 100% specificity. Kappa analysis showed substantial interobserver agreement for MRI. Ultrasound showed a 94% accuracy rate, a 94% positive predictive value, a 100% negative predictive value, 100% sensitivity, and 89% specificity. There was no statistical significance between the accuracy of MRI and US. We conclude that MRI and US imaging should both be considered when forearm interosseous membrane integrity is in question.

Adult↗

PubMed2002

Treatment of distal radius fractures with external fixation: technical considerations for rehabilitation.

Wrist external fixation with or without K-wire stabilization has been shown to be a reliable treatment method for unstable fractures of the distal radius. The technique of external fixation of the wrist has been historically based on the premise that fracture reduction can be achieved and maintained using the principles of ligamentotaxis. It is now well recognized that sustained longitudinal traction applied with a wrist external fixator can lead to complications. This review outlines the authors' preferred technique of using the external fixator as a neutralization device rather than as a traction device. The absence of sustained radiocarpal traction during distal radius fracture healing may facilitate postoperative rehabilitation.

Journal Article↗

PubMedDate not supplied

Continuous regional anesthesia before surgical peripheral sympathectomy in a patient with severe digital necrosis associated with Raynaud's phenomenon and scleroderma.

BACKGROUND AND OBJECTIVE: Digital ischemia and necrosis caused by Raynaud's phenomenon in patients with connective tissue diseases may not respond to medical therapy and may have major adverse effects on quality of life. We describe the use of continuous ambulatory regional anesthesia for diagnosis and treatment before peripheral sympathectomy in a patient with secondary Raynaud's phenomenon. CASE REPORT: A 55-year-old man with progressive systemic sclerosis and secondary Raynaud's phenomenon presented with severe pain and digital necrosis that were refractory to maximal medical treatment and thoracic sympathectomy. Continuous ambulatory regional analgesia increased digital temperature from 32.3 degrees C at baseline to 34.4 degrees C after 80 minutes. An increase in digital flow was documented by Doppler ultrasound measurements made ventrally at the point of greatest pulsation of the radial artery. Subsequent peripheral sympathectomy resulted in restoration of nutrient flow with healing of ulcers and alleviation of pain. CONCLUSIONS: Continuous ambulatory regional anesthesia appears effective as a treatment bridge for vasospasm and ischemia associated with secondary Raynaud's phenomenon. The enhancement of peripheral blood flow achieved with the regional anesthetic technique suggests that surgical peripheral sympathectomy may provide long-term benefits.

Anesthesia, Conduction↗

PubMedDate not supplied

Evaluation of collateral ligament injuries of the metacarpophalangeal joints with magnetic resonance imaging and magnetic resonance arthrography.

Injuries of the collateral ligaments of the metacarpophalangeal (MCP) joints of the hand require accurate diagnosis and prompt treatment to prevent loss of function. The most common and well-known collateral ligament injury is injury to the ulnar collateral ligament of the first MCP joint of the hand, often referred to as a gamekeeper injury. Although less common, injuries involving the collateral ligaments of the second through fifth digits and the radial collateral ligament of the first digit also occur. The diagnosis of collateral ligament injury is often made clinically, however, magnetic resonance imaging and magnetic resonance arthrography of the MCP joints can be very useful in the evaluation of severity of the injury. This provides important information for the hand surgeon and aids in treatment planning. Imaging of the collateral ligaments requires small fields of view and several technical considerations can provide improved image quality. These factors will be discussed and illustrated in this article.

Arthrography↗

PubMedDate not supplied

New-generation implant arthroplasties of the finger joints.

Prosthetic replacement in the hand must address such unique challenges as preservation of the collateral ligaments, tendon balancing, and stability. Some recently developed implant arthroplasties of the metacarpophalangeal and proximal interphalangeal joints have anatomically designed articular components; others have non-cemented, press-fit, carefully contoured intramedullary stems. The rationale behind developing the unlinked or semiconstrained prosthesis with anatomic geometry is that it would create balanced forces across the joint. Low-profile, anatomically designed implants limit the amount of bone removed and preserve the integrity of the collateral ligaments. A metacarpophalangeal joint implant with an elliptical metacarpal head and a nonfixed center of rotation can enhance stability in flexion through greater articular contact. A proximal interphalangeal joint implant that preserves the collateral ligaments also can achieve improved stability. Component loosening is not an early complication with these recent designs, and arc of motion is satisfactory.

Arthroplasty, Replacement↗