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Revision peripheral nerve surgery
Vora, Anand M; Schon, Lew C
The treatment of chronic neuropathic pain with revision surgical procedures can be beneficial. A thorough evaluation can help to guide treatment to optimize outcome. With an increasing understanding of the pain-generating mechanisms and the appropriate application of surgical interventions, quality of life and function continues to be improved in patients who have otherwise significant disability.
PMID: 15165585
ISSN: 1083-7515
CID: 3802102
Treatment of stage II posterior tibial tendon deficiency with flexor digitorum longus tendon transfer and calcaneal osteotomy
Myerson, Mark S; Badekas, Athanasios; Schon, Lew C
BACKGROUND:To assess the efficacy of surgical correction of stage II tibial tendon deficiency with medial translational calcaneus osteotomy and flexor digitorum longus tendon transfer to the navicular, the authors retrospectively reviewed results of treatment of stage II posterior tibial tendon deficiency in 129 patients for whom surgery was performed between 1990 and 1997. METHODS:The indication for surgery included tendon weakness, flexible deformity, and foot pain refractory to nonsurgical treatment. All patients had a painful flexible flatfoot without fixed forefoot supination deformity (stage II). A medial translational osteotomy of the calcaneus and transfer of the flexor digitorum longus tendon into the navicular were done. The patients were examined, radiographs were obtained, and isokinetic evaluation of both feet was performed at a mean of 5.2 years postoperatively. The American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot Scale and Short Form Health Surgery (SF-36) were used to evaluate patients postoperatively. RESULTS:The mean AOFAS score at follow-up was 79 points (range, 54-93). There were seven significant complications in six patients. Isokinetic inversion and plantarflexion power and strength were symmetric with the contralateral limb in 95 patients, mildly weak in 18 patients, and moderately weak in eight patients. Subtalar joint motion was normal in 56 (44%), slightly decreased in 66 (51%), and moderately decreased in seven patients (5%). Correction was significant (p < .05) in all four radiographic parameters evaluated. Patients were entirely satisfied (118 patients), partially satisfied (seven patients), or dissatisfied (four patients). Further, 125 (97%) experienced pain relief, 121 (94%) showed improvement of function, 112 (87%) experienced improvement in the arch of the foot, and 108 (84%) were able to wear shoes comfortably without shoe modifications or orthotic arch support. CONCLUSIONS:The surgical correction of stage II posterior tibial tendon deficiency with medial translational calcaneus osteotomy and flexor digitorum longus tendon transfer to the navicular yielded excellent results with minimal complications and a high patient satisfaction rate.
PMID: 15319100
ISSN: 1071-1007
CID: 3802112
Clinical results with the Ludloff osteotomy for correction of adult hallux valgus
Chiodo, Christopher P; Schon, Lew C; Myerson, Mark S
BACKGROUND:Biomechanically, the Ludloff osteotomy fixed with lag screw compression has been shown to be more rigid than proximal crescentic and other proximal first metatarsal osteotomies for correction of symptomatic hallux valgus with a moderate to severe increase in the first intermetatarsal angle. The Ludloff osteotomy may, therefore, have a lower incidence of dorsal malunion and transfer metatarsalgia than other proximal first metatarsal osteotomies, such as the crescentic or chevron. METHODS:We reviewed the results of 82 consecutive cases of moderate to severe hallux valgus deformities corrected with the Ludloff oblique metaphyseal-diaphyseal osteotomy of the first metatarsal combined with a distal soft-tissue procedure and medial eminence resection. RESULTS:Follow-up was possible in 70 cases (85%) at an average of 30 months (range, 18 to 42 months). Preoperatively, the mean hallux valgus and first intermetatarsal angles were 31 degrees and 16 degrees, respectively. Postoperatively, these values improved to an average of 11 degrees and 7 degrees. In the sagittal plane, the first metatarsal was plantarflexed by an average of 1 mm, and there were no symptomatic transfer lesions of the second metatarsal. The mean AOFAS hindfoot score improved from 54 to 91 points. Complications included prominent hardware requiring removal (5), hallux varus (4), delayed union (3), superficial infection (3), and neuralgia (3). CONCLUSIONS:The use of the Ludloff oblique first metatarsal osteotomy resulted in excellent correction of the first intermetatarsal angle in patients with moderate to severe hallux valgus. With the plane of the osteotomy and rigidity of fixation, immediate ambulation was possible with minimal risk of dorsiflexion malunion of the first metatarsal.
PMID: 15363373
ISSN: 1071-1007
CID: 3802122
Efficacy of a new pressure-sensitive alarm for clinical use in orthopaedics
Schon, Lew C; Short, Kelly W; Parks, Brent G; Kleeman, T Jay; Mroczek, Kenneth
The current study evaluated a new pressure alarm and compared the ability of subjects to limit weightbearing to 20 lb with and without the alarm. The 28 subjects were divided into four groups (Group 1, n = 7, mean age, 33 years, with normal sensation; Group 2, n = 7, mean age, 59 years, with normal sensation; Group 3, n = 6, mean age, 56 years, without protective lower limb sensation, and Group 4, n = 8, mean age, 39 years, with transtibial amputation). All subjects were instructed in partial weightbearing ambulation and then practiced weight shifting onto a scale set at 20 lb for 2 minutes. Average peak force was measured using the F-scan in-shoe sensor while subjects ambulated in two trials: one with a deactivated pressure alarm and the other with an activated alarm. Data were analyzed using two-tailed t tests. In Groups 1, 2, and 4, significantly lower average peak force with the activated alarm versus deactivated alarm occurred in 43%, 86%, and 100% of subjects, respectively. Weightbearing was limited to less than 20 lb with the activated alarm in 86%, 57%, 33%, and 38% of subjects versus 71%, 14%, 0%, and 0% of subjects with the deactivated alarm, respectively.
PMID: 15232455
ISSN: 0009-921x
CID: 779812
Topography of the distal tibial nerve and its branches
Lumsden, David B; Schon, Lew C; Easley, Mark E; Duouguih, Wiemi A; Anderson, Claude D; Miller, Stuart D; Ottey, Deron K
The tibial nerve trunk and its branches were dissected in 20 embalmed cadaver legs and the relative topographic anatomy was defined at 3-cm intervals up to 15 cm proximal to the medial malleolar-calcaneal (MMC) axis. Each nerve branch was found in various locations. The calcaneal nerve was found to descend from medial to posteromedial. It was never found anterolaterally and only rarely laterally. The lateral plantar nerve was found to rotate externally from lateral and posterolateral to lateral and posteromedial as it descends. This nerve was not found medially or anteromedially. The first branch of the lateral plantar nerve was indistinguishable from the trunk of the tibial nerve descending medially to between the lateral plantar and calcaneal nerves. The overall pattern of the medial plantar nerve was an internal rotation from anteromedial (proximal) to anterior (distally). It was not found posteriorly. The flexor hallucis longus motor branch was located an average of 17.9 cm (range, 10-24 cm) proximal to the MMC axis. Preliminary application of these data has facilitated surgical dissection and afforded an understanding of how tibial nerve trunk pathology correlates with clinical manifestations.
PMID: 14524520
ISSN: 1071-1007
CID: 3802062
Arthrodesis of the fourth and fifth tarsometatarsal joints of the midfoot
Raikin, Steven M; Schon, Lew C
Maintaining mobility of the fourth and fifth tarsometatarsal joints has been reported to be important in arthrodesis of the midfoot. A review of the records at a tertiary care center of 23 patients (28 feet) with arthrodesis of these joints and a minimum 2-year follow-up showed that 22 complete midfoot arthrodeses were performed as part of the correction for a neuroarthropathic rocker-bottom deformity. Six arthrodeses of the fourth and fifth metatarsal joints were performed on normosensate feet with painful arthritis involving the lateral joints. Clinical and radiographic fusion occurred in 26 of 28 feet. Comparing average preoperative and postoperative scores, functional incapacity from lateral midfoot pathology decreased (8.4/10 to 2.2/10), overall pain scores improved (5.1/10 to 1.3/10), pain scores in the arthritic subgroup decreased (8.2/10 to 2.4/10), and the modified overall AOFAS midfoot score improved (35/100 to 78/100).
PMID: 12956562
ISSN: 1071-1007
CID: 3802052
Controversies in amputation surgery
Pinzur, Michael S; Pinto, Marco A Guedes de Souza; Schon, Lew C; Smith, Douglas G
Amputation surgery should be the first step in the rehabilitation of a patient with a nonfunctional limb, rather than the final step in treatment. When faced with a difficult decision regarding lower extremity amputation compared with attempted limb reconstruction, expectations for a reasonable outcome must be determined. After reasonable goals have been set, the surgery should be directed toward interfacing with a prosthetic limb. Current surgical techniques of lower extremity amputation, paying special attention to transosseous versus disarticulation amputation, help to optimize prosthetic limb fitting and functional rehabilitation. With the evolution of end-bearing amputation levels, there is resurgent interest in the bone bridging technique of Johann Ertl and interest in a new pneumatic immediate postoperative prosthetic limb fitting system.
PMID: 12690870
ISSN: 0065-6895
CID: 3802042
Intramedullary rod fixation compared with blade-plate-and-screw fixation for tibiotalocalcaneal arthrodesis: a biomechanical investigation
Chiodo, Christopher P; Acevedo, Jorge I; Sammarco, V James; Parks, Brent G; Boucher, Henry R; Myerson, Mark S; Schon, Lew C
BACKGROUND:Achieving stable fixation when performing tibiotalocalcaneal arthrodesis can be challenging, especially in osteopenic bone. The purpose of the current investigation was to compare the stiffness and fatigue endurance of blade-plate-and-screw fixation with intramedullary rod fixation in a cadaveric model. METHODS:In ten matched pairs of fresh-frozen cadaveric legs, a tibiotalocalcaneal arthrodesis was performed with use of a blade-plate and a 6.5-mm sagittal screw in one leg and with use of an intramedullary rod in the contralateral leg. After an initial load-deformation curve was obtained, each specimen was loaded to 270 N through 250,000 cycles at a rate of 3 Hz. RESULTS:Blade-plate-and-screw fixation resulted in significantly higher mean initial and final stiffness and decreased plastic deformation than did intramedullary rod fixation. In addition, there was an inverse correlation between bone-mineral density and the difference in plastic deformation noted between the specimens of each pair. CONCLUSIONS:Blade-plate fixation is biomechanically superior to intramedullary fixation for tibiotalocalcaneal arthrodesis.
PMID: 14668514
ISSN: 0021-9355
CID: 3802072
Tendon injuries in acute ankle sprains
Chapter by: Schon, Lew C; Anderson, Claude D
in: The unstable ankle by Nyska, Meir; Mann, Gideon (Eds)
Champaign, IL : Human Kinetics, 2002
pp. ?-?
ISBN: 9780880118026
CID: 3803462
Deep burial of resected nerve in bone: a simple technique
Melamed, Eyal A; Schon, Lew C
PMID: 12398150
ISSN: 1071-1007
CID: 3802032