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Dive into the research topics where Roger A. Mann is active.

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Featured researches published by Roger A. Mann.


Foot & Ankle International | 1992

Possible epidemiological factors associated with rupture of the posterior tibial tendon.

George B. Holmes; Roger A. Mann

Rupture of the posterior tibial tendon has been postulated to occur, in part, as a result of degenerative changes to the tendon. This possibility was examined by a review of 67 patients (average age 57 years) diagnosed with rupture of the posterior tibial tendon. Forty-five of the 67 patients (60%) had one or more of the following positive medical histories: (1) hypertension, (2) obesity, (3) diabetes mellitus, (4) previous surgery or trauma about the medial aspect of the foot, or (5) steroid exposure. Thirty-five patients (52%) had either hypertension, diabetes mellitus, or obesity. A statistical correlation was demonstrated between rupture of the posterior tibial tendon and obesity (P = .005) and to a lesser extent hypertension (P = .025). These disorders have been uniformly associated with an acceleration of the degenerative processes associated with aging, commonly via an acceleration of microvascular and macrovascular diseases. An additional vascular risk is implicated by the known zone of hypovascularity of the posterior tibial tendon and risk of rupture secondary to systemic or local injections of corticosteroids. The prevalence of posterior tibial tendon rupture parallels the degenerative processes of aging, hypertension, diabetes mellitus, and obesity. Additionally, the effects of corticosteroids and local surgical procedures may further be associated with local vascular impairment and eventual rupture.


Journal of Bone and Joint Surgery, American Volume | 1965

DEGENERATION OF IMMOBILIZED KNEE JOINTS IN RATS; HISTOLOGICAL AND AUTORADIOGRAPHIC STUDY.

T. H. Thaxter; Roger A. Mann; Carl E. Anderson

This is a histological and autoradiographic study of certain factors responsible for degeneration occurring in immobilized normal rat knees. Knees which have been denervated, immobilized and denervated, and immobilized with and without weight-bearing were studied. The weight-bearing and non-weight-b


Clinical Orthopaedics and Related Research | 1998

Thromboembolism after foot and ankle surgery : A multicenter study

Mark S. Mizel; H. Thomas Temple; James D. Michelson; Richard G. Alvarez; Thomas O. Clanton; Carol Frey; Alan P. Gegenheimer; Shepard R. Hurwitz; Lowell D. Lutter; Martin G. Mankey; Roger A. Mann; Richard A. Miller; E. Greer Richardson; Lew C. Schon; Francesca M. Thompson; Marilyn L. Yodlowski

Thromboembolic disease presents a potentially fatal complication to patients undergoing orthopaedic surgery. Although the incidence after hip and knee surgery has been studied and documented, its incidence after surgery of the foot and ankle is unknown. For this reason, a prospective multicenter study was undertaken to identify patients with clinically evident thromboembolic disease to evaluate potential risk factors. Two thousand seven hundred thirty-three patients were evaluated for preoperative risk factors and postoperative thromboembolic events. There were six clinically significant thromboembolic events, including four nonfatal pulmonary emboli, after foot and ankle surgery. The incidence of deep vein thrombosis was six of 2733 (0.22%) and that of nonfatal pulmonary emboli was four of 2733 (0.15%). Factors found to correlate with an increased incidence of deep vein thrombosis were nonweightbearing status and immobilization after surgery. On the basis of these results, routine prophylaxis for thromboembolic disease after foot and ankle surgery probably is not warranted.


Foot & Ankle International | 1996

Popliteal Sciatic Nerve Block for Postoperative Analgesia

Kurt M. Rongstad; Roger A. Mann; David Prieskom; Steve Nichelson; Greg A. Horton

Eighty-six patients were evaluated prospectively following the placement of a sciatic nerve block in the popliteal fossa after a major foot or ankle operation. Needle placement was guided by a peripheral nerve stimulator and 30 ml of 0.5% bupivacaine with epinephrine was used. Ninety-seven percent of patients had a successful block. Only one patient had severe discomfort during the block placement. The block lasted an average of 20 hours. During the first 24 hours after surgery, patients took an average of three hydrocodone tablets. Twenty-two of the 23 patients who had had previous major foot or ankle surgery found that the block was better than their previous pain control regimen. No patient had complications related to the block and 95% were satisfied and would have the block again.


Foot & Ankle International | 1995

Surgical Correction of Rheumatoid Forefoot Deformities

Roger A. Mann; Mark E. Schakel

Surgical correction of severe rheumatoid forefoot deformities with resection arthroplasties of the lesser metatarsal phalangeal joints and arthrodesis of the first metatarsal phalangeal joint resulted in a significant long-term improvement with respect to shoe wear, pain, and the ability to stand and walk in 95% of the patients. Ninety percent had a good or excellent functional result. There was minimal recurrence of deformity. Modifications of the procedure with maintenance of the proximal phalangeal bases and K-wire fixation of the metatarsal phalangeal arthroplasty and interphalangeal joints resulted in an improved cosmetic result and simplified postoperative management with an equal functional result and no increase in recurrence of deformity or complications.


Foot & Ankle International | 1996

Advanced Hallux Valgus Deformity: Long-Term Results Utilizing the Distal Soft Tissue Procedure and Proximal Metatarsal Osteotomy

Sharon M. Dreeben; Roger A. Mann

A series of 28 cases with a moderate to severe hallux valgus deformity and intermetatarsal angle of 14° or greater was followed an average of 5½ years to determine whether any significant loss of correction occurred. All feet were treated with a distal soft tissue procedure and proximal metatarsal osteotomy. The average correction of the intermetatarsal angle was 13.2° (7–20°), and the average loss of correction was 1.4°; the average correction of the hallux valgus angle was 26.7° (−2° to 48°), and the average loss of correction was 3.8°. In three cases, a recurrent deformity developed; in three other cases, a hallux varus deformity developed, two of which were symptomatic. Patient satisfaction was 85%. This study indicates that in most patients with a hallux valgus deformity and an intermetatarsal angle of 14° or greater, there is sufficient inherent stability of the first metatarsocuneiform joint that it does not require stabilization to obtain a satisfactory long-term result.


Foot & Ankle International | 2004

Functional Evaluation of the Scandinavian Total Ankle Replacement

Chris O. Dyrby; Loretta B. Chou; Thomas P. Andriacchi; Roger A. Mann

The purpose of this study was to evaluate the function of the ankle joint during walking before and after Scandinavian Total Ankle Replacement (STAR). Nine patients (six males and three females) with an average age of 65 years, scheduled for unilateral total ankle replacement for osteoarthritis and rheumatoid arthritis, were evaluated both preoperatively and postoperatively in a gait analysis laboratory. Arthroplasty patients showed reduced range of motion at the ankle compared to normal controls. Postoperative arthroplasty subjects had significantly improved external ankle dorsiflexion moment, the moment that affects the plantarflexor muscles, when compared to their preoperative status. The moment in arthroplasty patients was increased, indicating improved function of the ankle joint.


Foot & Ankle International | 1998

Biplanar Chevron Osteotomy

Loretta B. Chou; Roger A. Mann; Mark M. Casillas

We retrospectively reviewed the results of using a biplanar chevron osteotomy performed on patients who presented with hallux valgus deformities with an increased distal metatarsal articular angle (DMAA). The study included 17 feet (14 patients) of 12 women and 2 men. The average follow-up was 33 months. The average American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-lnterphalangeal Clinical Rating Score was 91. Ten of the 14 patients (13 of 17 feet) stated that they would choose to undergo the procedure again. The hallux valgus angle was improved from an average of 22° to 18°, the intermetatarsal angle from 11° to 9°, and the DMAA from 16° to 9°. We have demonstrated this procedure to be useful in the treatment of symptomatic bunion deformities with an increased DMAA.


Foot & Ankle International | 1989

Relationship of Metatarsophalangeal Joint Fusion on the Intermetatarsal Angle

Roger A. Mann; David A. Katcherian

To evaluate the effect of fusion of the first metatarsophalangeal joint on the first intermetatarsal angle, a series of 62 consecutive first metatarsophalangeal fusions was reviewed. Of these, 47 had sufficient data to be included in this study. The results of this study showed that the change in the first intermetatarsal angle following a first metatarsophalangeal joint arthrodesis is directly proportional to the preoperative first intermetatarsal angle. Therefore, when a first metatarsophalangeal joint arthrodesis is performed on a patient with a wide intermetatarsal angle, a concomitant proximal first metatarsal osteotomy is usually not indicated.


Developmental Medicine & Child Neurology | 2008

Rectus femoris release in selected patients with cerebral palsy: a preliminary report.

David H. Sutherland; Loren J. Larsen; Roger A. Mann

Two theories concerning the effects of surgical release of the proximal origins of the rectus femoris in spastic patients are (1) that release reduces hip flexion contracture and lumbar lordosis and diminishes crouch, and (2) that release primarily enhances early swing‐phase knee flexion.

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Verne T. Inman

University of California

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Alan P. Gegenheimer

Naval Medical Center Portsmouth

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Carol Frey

University of Southern California

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