Biomedical subjects

Edward Akelman

Publications and source records attributed to Edward Akelman.

11 recordsLinked to original sources

PubMed2005

Thumb carpometacarpal arthroscopy: a topographic, anatomic study of the thenar portal.

Arthroscopic treatment of osteoarthritis of the thumb carpometacarpal joint has been well described; however, the current site of the 2 working portals, especially the 1-R portal, may be complicated by neurovascular morbidity. This is owing to the close proximity of these portals to important nerves and vessels surrounding the carpometacarpal joint. We studied 7 cadaveric wrists to map out the topographic, anatomic, and arthroscopic position of a new thenar portal. We hypothesized that it would increase considerably the safe zone distances of the portal from vital structures of the joint compared with the traditional portals. This study showed that the thenar portal increases considerably the safe zone of the portal from the sensory branches of the radial nerve and the radial artery and does not put the motor branch of the median nerve at risk. In addition the thenar portal allows for better visualization of the carpometacarpal joint, which leads to improved ability to perform arthroscopic trapeziectomy.

Aged↗

PubMed2005

In vivo radiocarpal kinematics and the dart thrower's motion.

BACKGROUND: Wrist motion is dependent on the complex articulations of the scaphoid and lunate at the radiocarpal joint. However, much of what is known about the radiocarpal joint is limited to the anatomically defined motions of flexion, extension, radial deviation, and ulnar deviation. The purpose of the present study was to determine the three-dimensional in vivo kinematics of the scaphoid and lunate throughout the entire range of wrist motion, with special focus on the dart thrower's wrist motion, from radial extension to ulnar flexion. METHODS: The three-dimensional kinematics of the capitate, scaphoid, and lunate were calculated from serial computed tomography scans of both wrists of fourteen healthy male subjects (average age, 25.6 years; range, twenty-two to thirty-four years) and fourteen healthy female subjects (average age, 23.6 years; range, twenty-one to twenty-eight years), which yielded data on a total of 504 distinct wrist positions. RESULTS: The scaphoid and lunate primarily flexed or extended in all directions of wrist motion, and their rotation varied linearly with the direction of wrist motion (R2= 0.90 and 0.82, respectively). Scaphoid and lunate motion was significantly less along the path of the dart thrower's motion than in any other direction of wrist motion (p < 0.01 for both carpal bones). The scaphoid and lunate translated radially (2 to 4 mm) when extended, but they did not translate appreciably when flexed. CONCLUSIONS: The dart thrower's path defined the transition between flexion and extension rotation of the scaphoid and lunate, and it identified wrist positions at which scaphoid and lunate motion approached zero. These findings indicate that this path of wrist motion confers a unique degree of radiocarpal stability and suggests that this direction, rather than the anatomical directions of wrist flexion-extension and radioulnar deviation, is the primary functional direction of the radiocarpal joint.

Adult↗

PubMed2005

Giant cell tumor of tendon sheath.

Neoplasms of the hand are not common. Giant cell tumor of tendon sheath (GCTTS) is the most common primary tumor of the hand. Many different theories have recently been proposed as to whether GCTTS is a neoplasm or a localized reactive process. We believe the evidence supports a neoplastic origin. Although the origin is still not proved, the presentation, diagnosis, and treatment of GCTTS have been clear for a long time.

Giant Cell Tumors↗

PubMed2004

Metacarpophalangeal joint mechanics after 3 different silicone arthroplasties.

PURPOSE: This study was performed to compare metacarpophalangeal (MCP) joint mechanics after arthroplasty with 3 currently available silicone implants and to determine how postarthroplasty mechanics compares with the mechanics of the intact joint. METHODS: Planar 2-dimensional kinematic analysis was performed using digitized radiographs on 10 isolated fingers harvested from 5 fresh-frozen human cadavers. Radiopaque markers were affixed to the metacarpals and proximal phalanges, sewn to the flexor and extensor tendons, and placed into the stems and hinges of the implants. Each finger was tested intact, and after MCP joint replacement with 3 implants (Swanson [Wright Medical, Memphis, TN], Avanta [Avanta Orthopaedics, San Diego, CA], and NeuFlex [DePuy Orthopaedics, Warsaw, IN]). The fingers were secured to the test fixture and the flexor digitorum profundus flexor and extensor tendons were loaded with physiologic weights. Lateral radiographs were taken at approximately 10 degrees intervals and were digitized on a high-resolution scanner. Instantaneous center of rotation (ICR), tendon excursion, and tendon moment arm were calculated. Statistical analysis was performed using repeated measures one-way analysis of variance and Dunnett post tests. RESULTS: The ICRs of the intact and implanted MCPs did not follow a smooth path. The variability of the ICRs of the intact MCP joints was 2.1 +/- 0.8 mm. The variations in the Avanta and DePuy implants were similar (3.1 +/- 1.0 mm and 3.5 +/- 1.5 mm, respectively), whereas the Swanson implant was higher (4.9 +/- 1.7 mm). Implant pistoning was most pronounced with the Swanson implant, which moved 2.40 +/- 0.97 mm over the full range of motion. The Avanta and DePuy implants pistoned significantly less than the Swanson implant (1.05 +/- 0.45 mm and 0.69 +/- 0.31 mm, respectively). Flexor tendon excursion was greater for the intact joint when compared with all 3 implants while extensor tendon excursion was similar for all. Flexor tendon moment arm was similar for the intact joint and the Avanta and NeuFlex implants whereas the Swanson implant was reduced significantly; extensor tendon moment arms were similar for all. CONCLUSIONS: The ICR of the NeuFlex implant most closely matched that of the intact MCP joint. The Swanson implant had greater pistoning and dorsal-volar translation when compared with the intact joint and the Avanta and NeuFlex implants. The block-hinge type design of the Avanta and NeuFlex implants improved tendon moment arm overall when compared with the Swanson, likely imparting greater functional ability for finger motion. Overall the NeuFlex implant most closely matched the ICR, tendon excursion, and moment arm when compared with the intact native MCP joint.

Aged↗

PubMed2004

A technique for reducing splash exposure during pulsatile lavage.

Pulsatile lavage is a frequently used method among orthopaedic traumatologists at our institution in the management of open fractures and contaminated wounds. Due to the pressure generated by the pulsatile lavage systems, splash exposure in the operating room environment becomes an unavoidable occurrence. The potential exists for a mucocutaneous exposure for either the surgeon or the operating room personnel. We have devised a method of decreasing the exposure risk to surgeons and operating room personnel during the pulsatile lavage irrigation portion of the procedure. An x-ray cassette drape is placed over the affected limb with enough clamps to create a closed system. Then small holes are created for the pulsatile lavage and the suction tubing, and the irrigation procedure is begun. This inexpensive cassette cover has proved to be a substantial advantage in our institution for decreasing mucocutaneous exposure.

Adult↗

PubMed2004

Access and use of the internet in a hand surgery population.

Internet use is increasing and its applications to medicine and patient information are widening daily. Previous studies have focused on the quality and quantity of medical information on the Internet. The current study focuses on a population of 120 new patients presenting to a hand surgery practice. A questionnaire was used to analyse patterns of Internet access, use of the Internet to look up personal symptoms, and patients' opinions on the use of electronic mail by office staff. Results showed that approximately 90% of the group had some form of Internet access, with a significant age-related decrease in Internet access. Only 17% used the Internet to look up their symptoms, but this group was more likely to correctly match their self-diagnosis to the surgeon's diagnosis. On average, 65% of the study group favoured the use of electronic mail for office staff's communications with patients.

Adolescent↗

PubMed2004

The familial incidence of carpal tunnel syndrome in patients with unilateral and bilateral disease.

The controversy has been considerable regarding the incidence of familial carpal tunnel syndrome. Of particular interest is the relationship between bilateral disease and familial incidence. In this study, we compare the incidence of familial carpal tunnel syndrome in patients with the syndrome in one, both, or neither hands. We report a significantly greater incidence of familial carpal tunnel syndrome in those patients with bilateral disease than in a similar population of patients with either unilateral disease or no carpal tunnel syndrome. These results may imply inheritability of variations in the size of the tunnel or its contents, which would manifest themselves bilaterally and may cause a predisposition for developing the syndrome. Being aware of the propensity for bilateral disease may improve our ability to prevent and treat the disease.

Adolescent↗

PubMed2003

Biomechanical and anatomical consequences of carpal tunnel release.

Carpal tunnel syndrome is an exceedingly common orthopaedic problem in the United States. When conservative management is unsuccessful, most surgeons proceed to surgical treatment. Though the carpal tunnel release procedure is usually curative, many patients experience postoperative complications, such as scar sensitivity, pillar pain, recurrent symptoms, and grip weakness, regardless of whether the release was done through an open, mini-open, or endoscopic approach. The exact causes of these and other complications of carpal tunnel release remain unclear. Release of the carpal tunnel has an effect on carpal anatomy and biomechanics, including an increase in carpal arch width, carpal tunnel volume, and changes in muscle and tendon mechanics. We set out to review the morphological and biomechanical changes caused by carpal tunnel release with the goal of better understanding the root causes of postoperative complications. This article first reviews normal carpal tunnel anatomy and anatomic variations, then available surgical techniques for carpal tunnel release, and finally the literature on morphologic, physiologic and biomechanical alterations in the wrist after carpal tunnel release.

Carpal Tunnel Syndrome↗

PubMed2003

Carpal bone postures and motions are abnormal in both wrists of patients with unilateral scapholunate interosseous ligament tears.

PURPOSE: The recent ability to measure 3-dimensional in vivo carpal kinematics has facilitated the noninvasive study of complex carpal bone motion. METHODS: In this study we examined the flexion/extension carpal kinematics of both wrists in 8 patients with unilateral scapholunate interosseous ligament (SLIL) tears by using computed tomographic (CT) imaging and a markerless bone registration technique. Carpal bone neutral posture and flexion/extension motion of both wrists of the injured patients were compared with the same parameters in wrists of 10 uninjured male and female volunteers (normals). RESULTS: The neutral posture of the injured scaphoid and lunate were significantly more extended than those of normals. In these patients, however, the postures of the scaphoid and lunate in the contralateral uninjured wrists also were abnormal and were similar to those of the injured wrist. In addition, extension of the lunate and flexion of the scaphoid in both the injured and uninjured wrist were significantly different from normal but not different from each other. CONCLUSIONS: This study was unable to attribute altered carpal posture and motion to SLIL tears because abnormalities were found in both wrists of patients with unilateral injury. The etiology of abnormal wrist kinematics in the asymptomatic wrist of patients with unilateral tears of the scapholunate ligament is not known.

Adult↗

PubMed2003

A prospective study of outcome following mini-open carpal tunnel release.

Mini-open carpal tunnel release has been the focus of recent attention for surgical decompression of carpal tunnel syndrome. Other techniques such as standard open carpal tunnel release and endoscopic release have been well established, and outcomes, complications and results for these operations have been published widely. Our study uses the validated Levine Katz questionnaire for carpal tunnel syndrome to measure patient subjective outcomes at one year follow-up after mini-open carpal tunnel release. Thirty-four consecutive hands were enrolled prospectively with preoperative and postoperative questionnaires. Mean symptom severity scores per question improved from 2.8 to 1.3 and mean function severity scores per question improved from 2.6 to 1.3. Comparing our data to the historical cohort of Levine et al., there was a statistically significant improvement in postoperative outcomes in our population (p < 0.0001).

Adult↗

PubMed2002

Three-dimensional in vivo kinematics of the distal radioulnar joint in malunited distal radius fractures.

How malunion of the distal radius affects the kinematics of the distal radioulnar joint in vivo was evaluated. A novel computed tomography image-based technique was used to quantify radioulnar motion in both wrists of 9 patients who had unilateral malunited distal radius fractures. In the injured wrists dorsal angulation averaged 21 degrees +/- 6 degrees, radial inclination averaged 18 degrees +/- 5 degrees, and radial shortening averaged 21 +/- 3 mm. Clinically, the average range of motion of the injured wrists was 75 degrees +/- 25 degrees pronation and 73 degrees +/- 23 degrees supination. Kinematics of the radius during pronation and supination in the malunited forearms was indistinguishable from that in the uninjured forearms. In both the axis of rotation of the radius passed through the center of the ulnar head, although it shifted slightly ulnar and volar in supination and radial and dorsal during pronation. In contrast to previous in vitro biomechanical findings, there was no dorsovolar radial translation at the extremes of pronation or supination and no translation of the radius along the rotation axis. Soft tissues may play a larger role in limiting function than previously appreciated, and treatment may require correction of altered soft tissue structures as well as any abnormal bone anatomy.

Adolescent↗