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Deep burial of resected nerve in bone: a simple technique
Melamed, Eyal A; Schon, Lew C
PMID: 12398150
ISSN: 1071-1007
CID: 3802032
Mechanical comparison of cyclic loading in five different first metatarsal shaft osteotomies
Acevedo, Jorge I; Sammarco, V James; Boucher, Henry R; Parks, Brent G; Schon, Lew C; Myerson, Mark S
The purposes of the current study were: 1. to analyze the relative fatigue endurance of five different first metatarsal shaft osteotomies (proximal crescentic, proximal chevron, Ludloff, Mau, and Scarf), as performed on sawbone models using the most common fixation techniques (part I); and 2. to compare the two more commonly used techniques (per part I results) in matched-pair cadaver specimens (part II). In part I, the proximal chevron and Mau osteotomies were significantly more stable (P < or = 0.005) than all other osteotomies except the Ludloff. In part II, there was no significant difference in fatigue endurance between the proximal chevron and Ludloff osteotomies.
PMID: 12199384
ISSN: 1071-1007
CID: 3802022
Pedobarographic and musculoskeletal examination of collegiate dancers in relevé
Schon, Lew C; Edwards, William H B; McGuigan, Francis X; Hoffman, Jennifer
Twenty-one collegiate ballet pupils were evaluated via history/questionnaire, musculoskeletal assessment, and pedobarographs, focusing on factors (e.g., alignment of hip, knee, and foot) thought to affect the important and common second-position relevé in dance. In a blinded manner, three observers classified the pedobarographs (obtained by an independent examiner) according to force distribution through the foot. Most dancers bore weight through the toes and transmitted force on both the medial and central metatarsal heads, and some transmitted force through only one of these rays, but none transmitted force through the lateral ray alone. This analysis provides a baseline for future assessment of normal or abnormal dance maneuvers.
PMID: 12146776
ISSN: 1071-1007
CID: 3802012
Benefits of early prosthetic management of transtibial amputees: a prospective clinical study of a prefabricated prosthesis
Schon, Lew C; Short, Kelly W; Soupiou, Olga; Noll, Kenneth; Rheinstein, John
To evaluate the use of an immediate postoperative prosthesis (IPOP) for transtibial amputees, we compared patient outcomes from a prospective clinical study of 19 patients managed with an IPOP with those of a retrospective review of a matched historic control group of 23 patients managed with standard soft dressings. Data were analyzed with the Student's t-test, and significance was set at P = 0.05. The IPOP patients had no surgical revisions, whereas the patients with standard soft dressings had 11. This was a significant difference. IPOP patients also had significantly fewer postoperative complications and shorter times to custom prosthesis than did controls.
PMID: 12095119
ISSN: 1071-1007
CID: 3802002
A biomechanical study of two postoperative prostheses for transtibial amputees: a custom-molded and a prefabricated adjustable pneumatic prosthesis
Boucher, Henry R; Schon, Lew C; Parks, Brent; Kleeman, Jay; Dunn, Warren R; Badekas, Thanos; Noll, Kenneth; Melamed, Eyal
We evaluated an adjustable pneumatic prefabricated prosthesis and a rigid custom-molded prosthesis for immediate postoperative use. Twelve transtibial amputations were performed on cadaver limbs. Differential variable reluctance transducers were placed subcutaneously across the wound edge medially and laterally. The limbs were then placed in either the pneumatic prosthesis (five limbs) or the rigid prosthesis (seven limbs). The specimens underwent static and cyclic loading to simulate weight bearing. The strain readings for static and cyclic loading were greater in the rigid prosthetic group. Only the mean medial strain measurement after cyclic loading was statistically significant. The results demonstrate that the pneumatic prosthesis places less strain across the wound than a rigid prosthesis.
PMID: 12043992
ISSN: 1071-1007
CID: 3801982
Two modifications of the Weil osteotomy: analysis on sawbone models
Melamed, Eyal A; Schon, Lew C; Myerson, Mark S; Parks, Brent G
Second metatarsal osteotomies (30 degrees angle to shaft) were performed in 40 sawbones with: 1. head shifted proximally 5 mm; 2. head shifted proximally 10 mm; 3. 5-mm slice resected and head shifted proximally 5 mm; or 4. 5-mm dorsally based wedge resected and head shifted proximally 5 mm. Bone slice resection resulted in shortening (16.4+/-1.7 mm) and mild plantar displacement of the head (3.5+/-0.8 mm). Bone wedge excision resulted in moderate shortening (7.8+/-0.9 mm) and essentially no plantar displacement of the head (0.8+/-1.4 mm).
PMID: 12043983
ISSN: 1071-1007
CID: 3801972
[Airlimb. Initial experiences with a new immediate early management prosthesis with individually adjustable air chambers]
Ivanic, G M; Schon, L C; Badekas, T; Badekas, O; Homann, N C; Trnka, H J
Amputations of the lower extremity are still a common problem in diabetic feet and peripheral vasculopathies. The presented paper introduces a new device for an easier and faster mobilization of below-the-knee amputees. It is based on a new modular prostheses with individual inflatable air bladders. The compliance rate is higher with this device and it could be used from the day of surgery until the definitive prostheses is made. A biomechanical cadaver study with the prostheses will also be presented.
PMID: 12063921
ISSN: 0009-4722
CID: 3801992
Arthrodesis of the first metatarsophalangeal joint: a biomechanical study comparing memory compression staples, cannulated screws, and a dorsal plate
Neufeld, Steven K; Parks, Brent G; Naseef, George S; Melamed, Eyal A; Schon, Lew C
Arthrodesis of the first metatarsophalangeal joint of 21 matched pairs of cadaver toes was performed in order to compare the strength of three methods of internal fixation: 1. two crossed cannulated screws, 2. a dorsal plate with an oblique 0.062 K-wire, and 3. two compression staples with an oblique 0.062 K-wire. Biomechanical testing with plantar force was carried out, and gapping across the fusion site was measured. Stiffness, load to 1-mm displacement, and force to failure was determined for each specimen. Both the plate and screw constructs were statistically stronger in force to failure and initial stiffness than the compression construct. Compression staples have an advantage in their ease of insertion and theoretical continuous compressive force across an arthrodesis site, but should be supplemented with a cast or other external immobilization until union is achieved.
PMID: 11858342
ISSN: 1071-1007
CID: 3801962
The acquired midtarsus deformity classification system--interobserver reliability and intraobserver reproducibility
Schon, Lew C; Easley, Mark E; Cohen, Ilan; Lam, Peter W C; Badekas, Athanasios; Anderson, Claude D
A radiographic classification (Schon's) divides Charcot midtarsus deformities into four types identified by Roman numerals (I to IV), according to the anatomical location of the pathological process,11 and an objective method of severity staging using radiographic criteria is introduced and tested. A beta stage is assigned if one of the following criteria is met: 1. a dislocation is present; 2. the lateral talar-first metatarsal angle is > or = 30 degrees; 3. the lateral calcaneal-fifth metatarsal angle > or = 0; or 4. the AP talar-first metatarsal angle is > or = 35 degrees. An alpha stage can be assigned when all four features are absent. Clinical features useful in assessing and managing these deformities have been associated with the various types and stages. To determine whether the classification system is valid, a study was performed. Two examination booklets and an instructional booklet designed to teach the method were distributed to 75 orthopaedic surgeons at the AOFAS summer meeting to test for intraobserver reproducibility and interobserver reliability. Information about the participants was recorded, and the tests were scored. The highest scores for correct responses were achieved by foot and ankle fellows, followed by orthopaedic residents. Attending orthopaedic surgeons achieved the lowest scores. The most common error was a type I deformity misidentified as a type II. The interobserver reliability for correctly classifying the deformities was 81%, and the intraobserver reproducibility was 97%. We concluded that this classification system, intended to clarify the patterns of acquired midfoot collapse, permits assignment of both anatomic type (I to IV) and degree of severity (alpha-beta) with high reliability and reproducibility. It can therefore be used as a tool for diagnosis, planning treatment, and assessing the prognosis.
PMID: 11826874
ISSN: 1071-1007
CID: 3801952
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