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Thromboembolism after foot and ankle surgery. A multicenter study
Mizel, M S; Temple, H T; Michelson, J D; Alvarez, R G; Clanton, T O; Frey, C C; Gegenheimer, A P; Hurwitz, S R; Lutter, L D; Mankey, M G; Mann, R A; Miller, R A; Richardson, E G; Schon, L C; Thompson, F M; Yodlowski, M L
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.
PMID: 9553551
ISSN: 0009-921x
CID: 3803242
Posttraumatic posterior tibialis tendon insertional elongation with functional incompetency: a case report [Case Report]
Marks, R M; Schon, L C
We present a case report and literature review of distal intrasubstance rupture of the posterior tibial tendon with progressive pes planovalgus secondary to tendon incompetence. Three months after a severe ankle sprain, a 25-year-old basketball player presented with ankle weakness and pain. Treatment by advancement of the posterior tibial tendon to the navicular and medial displacement osteotomy of the calcaneal tuberosity restored alignment, strength, and full function.
PMID: 9542993
ISSN: 1071-1007
CID: 3803232
Salvage of pseudoarthrosis after tibiotalar arthrodesis
Levine, S E; Myerson, M S; Lucas, P; Schon, L C
We retrospectively reviewed the treatment of a selected group of 23 patients with pseudoarthrosis after ankle arthrodesis who underwent revision arthrodesis at an average of 1.7 years (range, 0.3-17.0 years) after the initial, unsuccessful procedure. Fourteen patients underwent isolated revision tibiotalar arthrodesis, and 9 had an additional hindfoot arthrodesis (7 tibiotalocalcaneal, 2 pantalar) performed at the time of the procedure. Rigid internal fixation with screws was performed when possible, and, in patients with poor bone quality, an external fixator was used. Autogenous bone grafting was used in 14 patients where bone loss was present. Twenty-one of 23 patients had successful union (average, 14 weeks; range, 6-48 weeks). Two patients underwent successful arthrodesis but had persistent pain from reflex sympathetic dystrophy. Overall, 19 of 23 patients were satisfied with the surgery. We conclude that revision arthrodesis for tibiotalar pseudoarthrosis is a worthwhile procedure.
PMID: 9310771
ISSN: 1071-1007
CID: 3803222
Clinical and radiographic outcome of revision surgery for failed triple arthrodesis
Haddad, S L; Myerson, M S; Pell, R F; Schon, L C
Between 1987 and 1994, we treated 33 patients with surgical revision for failed triple arthrodesis, 28 (29 feet) of whom returned for final examination (mean, 4.4 years; range, 2-7 years). The average age of these 16 women and 12 men was 46 years (range, 14-69 years). Before the revision procedure, patients had undergone nonoperative therapies for an average of 3.7 years (range, 0.5-12 years) and an average of three foot operations (range, 1-6 operations) after the primary triple arthrodesis. All patients were managed with rigid internal fixation via cannulated screws and power staples. Calcaneal osteotomy and/or revision of the transverse tarsal arthrodesis via appropriate saw cuts and bone wedges were used. Iliac crest bone graft was added, when a bone block arthrodesis was required, for those patients with nonunion or ankle impingement. Arthrodesis was achieved in all 29 feet, although 4 patients (4 feet) (14%) required additional procedures for malunion (2 patients), deformity recurrence (1 patient), deep infection (1 patient), and skin graft (1 patient). Comparison of the average pre- (retrospective) and postoperative American Orthopaedic Foot and Ankle Society 94-point hindfoot and ankle scores showed a significant improvement: 31 points (range, 13-61 points) versus 59 points (range, 24-91 points), respectively (P < 0.05). On a scale of 0 to 10 points, average patient satisfaction was 7.8 points (range, 2-10 points). This study demonstrated a satisfactory improvement in patient outcome after surgical correction of failed triple arthrodesis. We conclude that such a revision, although complex, may be attempted to establish a plantigrade foot free of infection and able to wear shoes without and orthosis or brace.
PMID: 9278743
ISSN: 1071-1007
CID: 3803212
Avascular necrosis of the talus treated by core decompression
Mont, M A; Schon, L C; Hungerford, M W; Hungerford, D S
We reviewed 11 patients (17 ankles) who had had core decompression for symptomatic avascular necrosis of the talus before collapse. The Mazur grading system was used to assess function preoperatively and at final follow-up, and radiographs were graded according to the Ficat and Arlet (1980) classification modified for the ankle. At a mean follow-up of seven years (2 to 14) 14 ankles (82%) had an excellent or good outcome (Mazur scores > 80 points; pain scores > 40 points (41 to 50). The other three ankles required tibiotalar fusion at a mean of 13 months (5 to 20) after core decompression. We conclude that core decompression is a viable method of treatment for symptomatic avascular necrosis of the talus before collapse.
PMID: 8836081
ISSN: 0301-620x
CID: 3803202
Lower extremity musculoskeletal problems in dancers
Schon, L C; Weinfeld, S B
Ankle and foot problems are extremely common in the high-performance dance population. To adequately evaluate and treat these problems, the physician must possess knowledge of how the physical demands of dance affect the performer's body. A routine evaluation of the dancer, involving a team of orthopedists, dance instructors, and physical therapists familiar with dance mechanics, has been developed to facilitate recognition of the abnormal mechanics responsible for injury. This technique can be useful in prevention and early diagnosis of injury, thus minimizing lost performance time.
PMID: 8732797
ISSN: 1040-8711
CID: 3803192
Tendon transfer combined with calcaneal osteotomy for treatment of posterior tibial tendon insufficiency: a radiological investigation
Myerson, M S; Corrigan, J; Thompson, F; Schon, L C
We present the radiographic results after flexor digitorum longus tendon transfer combined with a medial displacement calcaneal osteotomy for the treatment of posterior tibial tendon insufficiency. Eighteen patients with posterior tibial tendon insufficiency were reviewed from 12 to 26 months after surgery. The 15 women and 3 men had a mean age of 54 years (range, 38-72 years). The talar-first metatarsal and talonavicular coverage angles were measured before and after surgery on the anteroposterior weightbearing radiographs. The mean preoperative talar-first metatarsal and talonavicular coverage angles were 21 degrees (range, 3-45 degrees) and 34 degrees (range, 0-55 degrees), respectively. The mean postoperative values for these angles were 8.5 degrees (range, 0-35 degrees) and 21 degrees (range, -30-45 degrees), respectively. The mean talar-first metatarsal angle decreased from 21 degrees to 8.5 degrees, a mean improvement of 12.5 degrees, and the mean talonavicular coverage angle decreased from 34 degrees to 21 degrees, a mean improvement of 13 degrees. On the lateral weightbearing radiographs, the talar-first metatarsal angle and the distance from the medial cuneiform to the floor were measured before and after surgery. The mean preoperative values were -22 degrees (range, -10 to -40 degrees) and 9 mm (range, 1-19 mm), respectively. The mean postoperative values were -9 degrees (range, +5 to -25 degrees) and 16 mm (range, 10-28 mm), respectively. The mean talar-first metatarsal angle decreased from -22 to -9 degrees (a mean improvement of 13 degrees), and the distance from the medial cuneiform to the floor increased from 9 to 16 mm (a mean improvement of 7 mm). We conclude that the use of a combined medial displacement osteotomy of the calcaneus with a tendon transfer for treatment of posterior tibial tendon insufficiency may offset the inherent weakness of the flexor digitorum longus transfer by reducing the antagonistic deforming force of heel valgus.
PMID: 8589811
ISSN: 1071-1007
CID: 3803182
The management of neuroarthropathic fracture-dislocations in the diabetic patient
Schon, L C; Marks, R M
Appropriate management for the diabetic patient with a fracture or sprain depends on recognition of "at-risk" factors. For patients with stable, minimally displaced injuries, conservative modalities (prolonged immobilization and non-weight-bearing) are sufficient. For patients with unstable or displaced fracture-dislocations, and whose general condition does not contraindicate surgery, open reduction and internal fixation, at times combined with external fixation, is recommended. Initial aggressive management can avoid or minimize the disastrous sequelae of a destructive neuroarthropathic process and can effect a biomechanically sound plantigrade, braceable, and shoeable lower extremity.
PMID: 7724199
ISSN: 0030-5898
CID: 3803122
Branches of the tibial nerve: anatomic variations
Davis, T J; Schon, L C
Anatomic variations in tibial nerve branches may help explain discrepancies between clinical examination and electrophysiologic tests as to the location of neuronal lesions. Dissection of 20 cadaveric feet (10 pair) along the course of the tibial nerve and its branches confirmed that it bifurcates within 2 cm of the medio-malleolar-calcaneal axis in 90% (18/20) and that it gives off frequent small branches with its accompanying vascular structures. Unlike other studies, however, we found that 60% had multiple calcaneal branches off the tibial nerve and that 20% evidenced previously undescribed accessory innervation to the abductor hallucis muscle from other than the medial plantar nerve.
PMID: 7697149
ISSN: 1071-1007
CID: 3803112
Dance screen programs and development of dance clinics
Schon, L C; Biddinger, K R; Greenwood, P
Dance movements can be stressful to the body, and the required extreme positions may place physiologic structures at risk for acute, subacute, or chronic injury. The authors designed a screening program, conducted by a team of physical therapists, orthopedists, and dance instructors, to evaluate dancers for musculoskeletal problems and to make recommendations that would improve movement compensation, strength, endurance, and mobility.
PMID: 7805111
ISSN: 0278-5919
CID: 3803132