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B D Adams

Publications and source records attributed to B D Adams.

34 records · Page 2Linked to original sources
PubMed1993

Strains in the articular disk of the triangular fibrocartilage complex: a biomechanical study.

The articular disk of the triangular fibrocartilage complex was studied using a video imaging system in a cadaveric laboratory experiment. Changes in disk configuration consistently occurred during pronation and supination and resulted in a nonuniform strain distribution that was dependent upon forearm position. Strains occurred primarily in the radioulnar axis of the disk, with dorsoanterior strains being negligible. Strains were concentrated in the radial portion of the disk and were highest with the forearm pronated. Application of a distraction load to the distal radioulnar joint to simulate the effect of axial wrist loading caused strains to increase the most in the radial portion. These findings suggest that joint distraction loading and forearm pronation are important components of the injury mechanism for the most common type of traumatic tear that occurs near the radial attachment of the disk.

Adult↗
PubMed1993

Effects of radial deformity on distal radioulnar joint mechanics.

A cadaver experiment was performed to study the effects of radial deformity on the kinematics of the distal radioulnar joint and the anatomic configuration of the triangular fibrocartilage. Radial shortening caused the greatest disturbance in kinematics and the most distortion of the triangular fibrocartilage. Decreased radial inclination and dorsal angulation caused intermediate changes. Dorsal displacement produced minimal changes. Radial deformity did not produce distal radioulnar joint dislocation. These results provide biomechanical evidence of an important relationship between radial malunion and persistent symptoms in the distal radioulnar joint.

Adult↗
PubMed1993

Biomechanical evaluation of distal radioulnar reconstructions.

Numerous reconstructive procedures have been described for the treatment of chronic instability of the distal radioulnar joint or instability of the stump of the resected distal ulna. This biomechanical study presents an evaluation of the three basic design types that have been used in reconstruction. The initial static stability provided by the reconstructions was tested and compared with the stability of the intact joint. Our findings show that all reconstructive procedures failed to restore natural joint stability. A radioulnar sling design was the most effective of the three types, whereas tenodesis procedures and ulnar collateral ligament reconstruction were much less effective in providing stability. We conclude that current designs have significant biomechanical shortcomings. On the basis of our observations during testing, we believe that improved designs will require an intra-articular reconstruction that more closely duplicates the biomechanical functions of the triangular fibrocartilage complex.

Adult↗
PubMed1993

Partial excision of the triangular fibrocartilage complex articular disk: a biomechanical study.

A cadaver study was performed to evaluate the effects of partial and complete excisions of the articular disk of the triangular fibrocartilage complex on the kinematics of the distal radioulnar joint and the structural integrity of the triangular fibrocartilage. An excision that did not violate the peripheral 2 mm of the disk and that comprised less than two thirds of the disk area resulted in no significant kinematic or structural changes, but larger excisions produced measurable changes. These results provide further support for limited excision of central triangular fibrocartilage complex tears.

Adult↗
PubMed1992

Biomechanical evaluation of chronic boutonnière reconstructions.

The magnitudes of the extensor forces generated across the proximal interphalangeal joint by the Littler-Eaton, Matev, Hellmann, and Fowler reconstructive procedures for posttraumatic chronic boutonnière deformity were measured in a laboratory study. The purpose of the experiment was to determine whether the mechanical design of a procedure had a significant impact on biomechanical performance. Results showed that each method produced adequate extensor forces and restored full proximal interphalangeal joint extension. There were few statistically significant differences among the procedures for the different joint angles and load conditions tested. The data suggest that the mechanical designs of these reconstructions are satisfactory for correction of the extensor deficit of the deformity. The preoperative condition of the finger is probably responsible for the variations seen in clinical results.

Biomechanical Phenomena↗
PubMed1992

Treatment of scaphoid nonunion with casting and pulsed electromagnetic fields: a study continuation.

This article presents a continuation of a study of the treatment of scaphoid nonunion with pulsed electromagnetic fields (PEMF) and cast immobilization. Fifty-four patients were reviewed. The overall success rate for healing has decreased since the previous review from 80% to 69%. Proximal pole fractures healed in 50%. Success in nonunions with associated radiographic evidence of avascular necrosis decreased from 89% to 73%. Although we believe that the indications for use of PEMF have not changed significantly, this study suggests that a successful outcome with PEMF and casting is less likely than previously reported. We believe that until additional clinical studies have further defined the indications, treatment protocol, and efficacy of this method PEMF treatment should be a secondary alternative to bone-grafting procedures.

Adolescent↗
PubMed1992

Hand tendon injuries in athletics.

Hand tendon injuries may be caused by acute trauma or chronic overuse. Although these injuries are common in athletics, specific diagnoses can be difficult to make and are often delayed. Early diagnosis is the key to a good outcome. Most hand tendon injuries do well with nonoperative treatment when initiated early. Long-term disruption of the delicate balance of muscle forces in the hand will lead to secondary changes that are often difficult to correct. Delay in treatment of overuse injuries may produce chronic inflammation that does not respond to conservative care and requires operative management. A sound knowledge of hand anatomy, awareness of the differential diagnosis, and a high index of suspicion are needed for proper care of the athletic hand injury.

Acute Disease↗
PubMed1991

Case report 667. Fibrolipomatous hamartoma of the median nerve.

Fibrolipomatous hamartoma of a nerve represents an uncommon soft-tissue tumor which typically involves the median nerve distribution near the wrist. Macrodactyly may or may not be present. The application of MRI using routine T1- and T2-weighted spin echo imaging sequences reveals serpiginous structures with low signal intensity. These structures probably represent the neural elements and associated perineural fibrosis. Further experience may allow for an accurate preoperative diagnosis of this tumor.

Child, Preschool↗
PubMed1990

Niebauer trapeziometacarpal arthroplasty.

A retrospective review of 22 Niebauer implant arthroplasties of the trapeziometacarpal joint for treatment of advanced osteoarthritis in 18 patients is reported. Mean follow-up was 2.4 years. Thirteen patients stated they had good pain relief, two were slightly improved, and three had no improvement. Six patients believed their functional status was improved, 10 were the same, and 2 were made worse. Thumb abduction and strength measurements were similar in the hands with operation and those without operation. Full opposition was present in 68% of thumbs with operation versus 93% of those thumbs without operation. Asymptomatic implant subluxation of 50% or less was present in 23% of thumbs. However, only 9% had symptomatic mechanical instability and these thumbs showed greater than 75% subluxation. Implant breakage and "silicone synovitis" was not evident on clinical and radiographic examination. Evaluation of the bony response around the implant stem revealed a consistently present sclerotic line. Although the design features of the Niebauer implant offer theoretical advantages for stability and fixation, this study does not demonstrate better results compared with other types of silicone trapezium implants. Therefore, a surgeon should choose this implant on the basis of a personal preference for ease of implantation and not for improved clinical results.

Adult↗
PubMed1990

Schultz metacarpophalangeal arthroplasty: a long-term follow-up study.

We describe a prospective, long-term evaluation of the Schultz metacarpophalangeal joint implant. The prosthesis is a semiconstrained, cemented implant with a ball-in-socket articulation. Thirty-six implants were followed for an average of 10.9 years. There was a progressive decrease in range of motion and strength and a recurrence of ulnar deviation. The neck of the proximal phalangeal component fractured in 39% of the joints. Periarticular heterotopic bone formed in all joints, but was extensive in only 22%. Although some lucency of the bone-cement interface was seen in 80% of the joints, no prosthetic loosening occurred in this series. Our results indicate that long-term, intramedullary cement fixation of relatively long-stemmed components can be satisfactory. However, the articulated portion of this implant does not consistently withstand the stresses transmitted across the joint and does not provide long-term joint stability.

Adult↗
PubMed1989

Responding to perceived needs of the twenty-first century: a case study in curriculum design.

Mercer University School of Medicine was established in response to the shortage of primary care physicians in medically underserved Georgia. Originally patterned after the McMaster model of medical education, Mercer found it necessary to modify the three academic programs of the first 2 years of a 4-year undergraduate medical education curriculum. Since accepting students in 1982, though, it has retained many of the essential qualities of problem-based learning and those educational experiences that prepare community responsive physicians to practice in medically underserved areas.

Curriculum↗
PubMed1988

Technical factors related to Herbert screw fixation.

We reviewed 24 patients treated for an acute fracture or a nonunion of the scaphoid bone using the Herbert screw. Mean follow-up in 22 patients who returned for examination was 17 months. The overall union rate was 67% for both acute fractures and nonunions. Fracture healing correlated strongly with technical factors of the procedure. The fracture failed to heal in seven of nine cases with poor scaphoid realignment, inaccurate jig placement, or improper screw length for a nonunion rate of 78%. Conversely, without these technical problems, 14 (93%) of 16 fractures achieved union. Applying Herbert's criteria, a satisfactory rating for clinical function was achieved in 59% of all patients and for patient satisfaction in 68% of all patients. Although the postoperative immobilization period was reduced using the screw, the final functional result in our nonunions was similar to that reported for the Russe bone grafting procedure. Appropriate modifications of the standard technique and recognition of equipment limitations may improve union rates.

Adolescent↗
PubMedDate not supplied

Radiographic and orthopedic evaluation of wrist trauma.

This paper was written to enable radiologists to contribute more usefully to the diagnosis and treatment of various wrist injuries. All imaging modalities are discussed to equip the radiologist for his difficult task. We present a systematic approach to the evaluation of wrist trauma patients beginning with initial plain films and proceeding through more invasive or sophisticated studies in order to achieve a definitive diagnosis. Toward this end a flow chart has been developed as a quick reference source. The authors have then described the anatomy and kinematics of the wrist to further the radiologist's understanding of the forces involved and the injuries produced by trauma. From this foundation individual injuries are then discussed together with the best methods of making the proper diagnosis of each. Criteria for adequate treatment of various injuries are also presented.

Fractures, Bone↗
PubMedDate not supplied

Assessment of thumb positioning in the treatment of ulnar collateral ligament injuries. A laboratory study.

In the treatment of ulnar collateral ligament injuries in the metacarpophalangeal joint of the thumb, a cast or splint is often molded with the thumb and hand positioned so the patient can return quickly to a particular sport or activity. However, it is unknown whether a given position of immobilization or whether an early rehabilitation program will compromise ligament healing by causing undue tension in the ligament. To better define acceptable positions for thumb immobilization and a safe range of motion, this laboratory study measured strain in the ulnar collateral ligament at different degrees of metacarpophalangeal joint flexion. Ligament strain was found to increase with increasing joint flexion; the most significant increases in strain occurred as the joint moved from 0 degree to 25 degrees of flexion, with the dorsal portion of the ligament demonstrating greater strain than the palmar portion. Based on these results, immobilization of the metacarpophalangeal joint in excessive flexion and unrestricted early rehabilitation exercises should be done with caution and guided by the grade of injury or the quality of repair.

Adult↗
PubMedDate not supplied

Wrist arthrodesis: review of current techniques.

Wrist arthrodesis is a well-established procedure that predictably relieves pain and provides a stable wrist for power grip. Although a variety of techniques for achieving a solid fusion have been described, the combination of rigid stabilization with a dorsal plate and autogenous cancellous bone grafting results in a high fusion rate and obviates the need for prolonged postoperative cast immobilization. Successful results with dorsal plating with or without local bone graft have recently been reported for patients with posttraumatic conditions. Rod or pin fixation is an established procedure for patients with inflammatory arthritis or a connective tissue disorder; however, plate fixation for these conditions is becoming a more acceptable alternative. Complications are relatively common and range from minor transient problems to major problems, such as wound dehiscence, infection, extensor tendon adhesions, and plate tenderness, which may require implant removal. Preoperatively, patients should be assessed for the presence of carpal tunnel syndrome, distal radioulnar joint arthritis, or ulnocarpal impaction syndrome, which may become or remain symptomatic after arthrodesis. Wrist arthrodesis results in a high degree of patient satisfaction with respect to pain relief and correction of deformity. Patients are able to accomplish most daily tasks and activities by learning to adapt to, and compensate for, the loss of wrist motion.

Arthrodesis↗