Foot and Ankle Surgery 1997
3: 147–157
Special report
Highlights of the Thirteenth Annual Summer Meeting of the American Orthopaedic Foot and Ankle Society, Monterey, California, 17–19 July 1997 E. TREPMAN 1 , L. D. LUTTER 2 AND P. E. SCRANTON Jr3 American Orthopaedic Foot and Ankle Society, Seattle, WA, USA
Introduction The Thirteenth Annual Summer Meeting of the American Orthopaedic Foot and Ankle Society (AOFAS) was held 17–19 July 1997 at the Hyatt Regency in Monterey, California. The meeting was attended by a record 462 registrants. Among those attending were 112 individuals from 17 countries outside the USA, including 45 from Italy. The sely packed scientific programme included two instructional courses, three symposia, ten scientific sessions, and two fireside chats, with over 80 lecture presentations and posters.
Instructional courses and fireside chats The meeting opened with an instructional course which emphasized critical analysis of the published orthopaedic literature. Apparently contradictory conclusions between different studies may be explained by differences in assumptions, patient selection criteria, and data presentation [1]. The use 1
Subsection Editor (Abstracts), Foot & Ankle International; Fellow, American Orthopaedic Foot and Ankle Society. 2 Editor-in-Chief, Foot & Ankle International; Past President, American Orthopaedic Foot and Ankle Society. 3 Programme Chairman, Thirteenth Annual Summer Meeting; Member-at-Large, American Orthopaedic Foot and Ankle Society. Publication does not constitute endorsement of content or validation of conclusions. Comparisons should be made with caution because statistical significance might not have been noted in the abstracts published in the conference programme. Correspondence: Sandy Vocke, Managing Editor, Foot & Ankle International Office, 1690 University Avenue, #B10, St. Paul, MN 55104, USA. 1997 Blackwell Science Ltd
of confidence intervals in data presentation was reviewed [2–4]. Later in the afternoon, the problems of statistical design and analysis in the performance of orthopaedic studies were further discussed in an informal session [5]. The early morning session on the second day of the conference included a review of general and specific rules in Current Procedural Terminology (CPT) coding for the foot and ankle, important in the USA for accurate reimbursement and avoiding illegal overcoding [6]. An informative discussion of specific examples followed in the late afternoon [7].
Symposia The clinical symposia consisted of invited lectures which addressed multiple aspects of complex clinical problems.
Symposium 1: Salvage of the fractured calcaneus The evaluation of acute and chronic calcaneal fractures, including specialized radiographic and imaging studies such as computed tomography (CT), was discussed [8]. The management of tarsal tunnel impingement and claw toes after calcaneal fracture was considered [9]. It was emphasized that treatment of the deformed, malunited calcaneus may depend on the features of the deformity, and may include a sliding osteotomy, wedge osteotomy, exostectomy, arthrodesis, or reconstructive osteotomy combined with an arthrodesis [10]. It was observed that in some
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cases, an arthrodesis in situ can aggravate lateral impingement, and that in performing a lateral ostectomy, it is important to remove an adequate amount of bone [11]. When subtalar or triple arthrodesis is selected, it may be done in situ or combined with lateral exostectomy, calcaneal osteotomy, bone block distraction arthrodesis, or open reduction and internal fixation [12].
Symposium 2: Foot and ankle injuries in the elite athlete The clinical evaluation of ankle injuries can be difficult, and in some instances, magnetic resonance imaging (MRI) may be helpful in the diagnosis of occult lesions such as osteochondral defect (OCD), tears of the lateral ligaments, or peroneal tendon pathology [13]. Ankle arthroscopy may be helpful as a diagnostic tool in cases of soft tissue impingement or OCD [13]. A general review of the diagnosis and management of stress fractures of the foot and ankle [14] was followed by a discussion of specific hindfoot fractures, including fracture of the lateral talus (caused by snowboarding), posteromedial and posterolateral talar tubercle, anterior process of calcaneus, and base of fifth metatarsal [15]. Achilles tendon rupture may, in some instances, be managed with early rehabilitation [16]. In the management of acute ankle sprains, immobilization with dorsiflexion and weightbearing may bring together the ends of the ruptured anterior talofibular ligament, prevent anterior subluxation, and stabilize the talus in the mortise [17].
Symposium 3: Management of progressive degenerative pes valgus This complex problem was introduced with a thorough review of the literature, definitions, and pathological characteristics of flatfoot deformity [18]. Congenital pes valgus may be associated with a tight heel cord, subtalar facet hypoplasia, or ligamentous laxity, whereas acquired flatfoot is more commonly a result of posterior tibial tendon insufficiency, rheumatoid arthritis, or plantar fascia insufficiency [18]. In some instances, orthoses may be useful because they may: (1) alter the foot–floor interface (bring the floor up to the foot); (2) control excessive motion; (3) compensate for deleterious contractures
(e.g. heel lift for Achilles contracture); (4) accommodate and provide cushioning for deformities; and (5) alleviate subfibular impingement [19]. Surgical reconstruction may include osteotomy, arthrodesis, and other salvage procedures [20–22].
Scientific sessions and poster exhibits The studies presented in the scientific sessions and poster exhibits were selected by peer review of submitted abstracts.
Session 1: Trauma A follow-up review of 117 (71%) of 164 intra-articular calcaneal fractures treated with open reduction and internal fixation using either an extended lateral (137 (84%)) or direct lateral (27 (16%) cases) approach showed good or excellent results in 69% of cases [23]. Complications included sural nerve paresthesia and major wound problems, but clinical outcome was independent of fracture severity [23]. In another study of 40 calcaneal fractures treated with extended lateral approach, complications included 16 (40%) cases of wound dehiscence [24]. There was a correlation between smoking and wound complications, but delayed wound healing did not change average time to weightbearing or long-term outcome [24]. In children under age 14 years who had sustained intra-articular calcaneal fracture, remodelling did not compensate for fracture displacement, and subtalar arthritis was identified in nine of 16 (56%) patients at average 13-year follow-up evaluation [25]. Open anatomic reduction and fixation was advised for juvenile calcaneal fractures that could not be anatomically reduced using closed or limited open techniques [25]. In 48 calcaneal fractures sustained while at work, the 30 intra-articular fractures resulted in greater average medical and compensation costs and greater average time off from work than the 18 nondisplaced fractures [26]. For intra-articular fractures, moderate or severe activity restriction was noted in greater than 80% of patients, a change in job status was required in 40% of patients, and subtalar arthrodesis had been done or was being considered in 40% of patients [26]. 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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In a study of 28 severe Lisfranc fracture– dislocations, 16 (57%) patients treated with open reduction and internal fixation had similar pain and functional outcome as six (21.5%) patients treated with primary partial (medial) arthrodesis; however, in six (21.5%) patients treated with primary complete arthrodesis (including the metatarsocuboid joints), there were four (67%) cases of forefoot stiffness and three (50%) cases of reflex sympathetic dystrophy [27].
Session 2: Tarsal arthrodesis At an average 49-year follow-up after triple arthrodesis, done mainly for neuromuscular imbalance, all patients had degenerative changes the ankle, and similar progressive arthritic changes were noted at the naviculocuneiform and tarsometatarsal joints [28]. However, despite deterioration of symptoms with time, including presence of pain and need for support in more than 70% of patients, more than 90% of patients were satisfied with the results of surgery [28]. In another follow-up study (average 19 years) following triple arthrodesis done mainly for structural deformity or arthrosis, subjective outcome was satisfactory or very satisfactory in 17 of 21 (81%) feet, even though there was difficulty with walking on non-level ground with 11 (52%) feet and with running in nine (43%) feet [29]. The other four (19%) feet with less than satisfactory subjective results were associated with painful ankle arthritis and varus hindfoot malposition [29]. Forty patients treated for acute calcaneal fracture, either non-surgically or with open reduction and internal fixation, subsequently underwent subtalar arthrodesis for post-traumatic arthritis [30]. At a mean 5-year follow-up evaluation after subtalar arthrodesis, 80% of patients had some residual pain, and outcome scores were independent of method used for treatment of the acute fracture [30]. In another study, ankle, subtalar, and triple arthrodeses were performed as outpatient procedures with regional anaesthesia and local bone grafting [31]. This method resulted in reduced length of hospital stay, estimated blood loss, and cost of the procedure compared with inpatient arthrodeses done using general anaesthesia and iliac crest bone grafting [31]. 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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Severe acquired flatfoot was managed with talonavicular arthrodesis and medial displacement calcaneal osteotomy in 14 patients [32]. At an average of 25 months after surgery, 12 (86%) of the patients were satisfied with the result, all patients had improvement of radiographic parameters of deformity, and the average AOFAS score was improved from 45 before surgery to 76 at follow-up evaluation [32].
Session 3: Biomechanics In a cadaver model of supramalleolar osteotomy in the loaded ankle, it was determined that a 10° valgus osteotomy caused a reduction of medial talar dome force from 70 N to 40 N (43%), whereas a 10° varus osteotomy caused an increase in medial talar dome force from 70 N to 107.5 N (54%) [33]. It was suggested that valgus supramalleolar osteotomy may be considered for treatment of medial ankle joint arthrosis [33]. In fifth metatarsal cadaver specimens, intact specimens loaded to failure had an average force to failure of 1000 N [34]. In simulated Jones fractures created by osteotomy and fixed with an intramedullary screw, the average force at initial displacement was 70 N, and force at complete displacement was 500–600 N; these forces were similar with a 4.5 mm, malleolar screw and a 4.5 mm, partially-threaded, cancellous, cannulated screw [34]. In a clinical study of chevron osteotomy for treatment of hallux valgus deformity in 19 feet, average hallux valgus angle improved by 7.1° in six feet treated with no fixation, 6.3° in seven feet treated with temporary wire fixation, and 9.5° in six feet fixed with a screw [35]. There was no difference in patient satisfaction between groups treated with or without fixation [35]. Roentgen stereophotogrammetric analysis with implanted tantalum markers was used to determine of motion of the unloaded tibiotalar, talocalcaneal, talonavicular, calcaneocuboid, and naviculocuneiform joints in healthy volunteers [36, 37]. The joint axis orientations varied between different individuals and different voluntary foot and ankle motions [36]. With voluntary plantarflexion–dorsiflexion of the foot ankle, the tibiotalar joint had the largest maximum range of motion; with pronationination, the talonavicular joint had the largest maximum range of motion [36]. The available range
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of motion of the talonavicular joint was twice that of the calcaneocuboid joint, and the joint axes of these two joints were consistently related but never parallel [37].
Session 4: The subtalar joint Anatomic variations of the subtalar joint resulted in complicated recovery from foot and ankle injury in a series of 13 patients [38]. In four patients with an abnormal posteromedial process, two were treated with open resection; in five patients with asymmetric subtalar joint development, three were treated with subtalar arthrodesis; and all four patients who had ball-and-socket ankle with complete subtalar coalition were treated non-surgically [38]. In a series of 41 patients, subtalar joint pain was evaluated with stress radiography, subtalar arthrography, and subtalar arthroscopy [39]. In sinus tarsi syndrome, generalized synovial proliferation was noted, and synovectomy was done; in isolated calcaneofibular ligament injury, there was synovitis localized to the lateral area of the subtalar joint, and ligament reconstruction was done; and in subtalar instability, partial rupture of the talocalcaneal interosseous ligament was noted, and this ligament was reconstructed arthroscopically [39]. A new radiographic view was designed to evaluate the coronal plane alignment of the calcaneus relative to the tibia [40]. The radiographic view was assessed with a cadaver model, and was used to evaluate postural stability in standing subjects [40]. In 48 patients with non-osseous tarsal coalition (27 (56%) talocalcaneal, 8 (17%) calcaneonavicular, and 13 (27%) naviculo-first cuneiform), histologic evaluation showed fibrocartilaginous tissue at the site of coalition, with no inflammatory cell infiltrate [41]. Nerve endings were identified only in the periosteum and articular capsule, but not in the fibrocartilaginous tissue of the coalition [41]. The three-dimensional position of the talus, calcaneus, navicular, and first metatarsal relative to the tibia was monitored in loaded cadavers using a magnetic tracking system, and a flatfoot deformity was created by sectioning peritalar soft tissue structures [42]. A computer-generated animation model was used to illustrate the complex joint movements, and bone-to-bone angles in the intact and flatfoot conditions were compared [42].
Session 5: Forefoot disorders In 22 patients with hallux valgus deformity and increased distal metatarsal articular angle (DMMA>9°), a distal biplanar chevron osteotomy was done, which included a medial closing wedge at the dorsal limb of the chevron cut [43]. At an average 24 months follow-up evaluation, 95% of the patients were satisfied, average correction of the DMMA was 10°, average correction of the hallux valgus angle was 8°, and the average first metatarsal shortening was 5.5 mm [43]. In a cadaver study in which proximal first metatarsal osteotomies were fixed and loaded to failure, it was demonstrated that a proximal biplanar wedge osteotomy with plantar plate fixation had significantly greater mean load to failure and mean stiffness than a proximal crescentic osteotomy [44]. At 5.1-year follow-up after cheilectomy for hallux rigidus in 22 individuals active in high-level sports, pain relief was noted in 88% of patients [45]. Average time to return to sports was 11.5 weeks, and average postoperative dorsiflexion was 48° [45]. There was a reduction of mean peak pressure under the first metatarsal head after surgery [45]. In another study, dorsal cheilectomy for hallux rigidus was done from a medial approach [46]. At an average 63 months postoperative follow-up evaluation of 52 patients (68 feet), average AOFAS Hallux Rating (preoperative, 45; follow-up, 83) and range of motion were improved, even though there was radiographic progression of the arthritis in 38 feet and recurrence of a dorsal osteophyte in 21 feet [46]. Crossover second toe deformity in 38 patients was managed with a flexor-to-extensor tendon transfer (22 feet) and an extensor digitorum brevis tendon transfer (20 feet) [47]. Results with the two procedures were variable, with 27 (71%) patients completely satisfied, eight (21%) patients partially satisfied, and three (8%) patients not satisfied [47].
Session 6: Ankle arthrodesis Ankle arthrodesis using a transfibular approach, cancellous screw fixation, and no additional bone graft, resulted in a 93% rate of primary fusion [48]. A high level of patient satisfaction was noted in 25 patients evaluated at an average 24 months after 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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surgery, but six patients with active litigation had a significantly lower average AOFAS Ankle–Hindfoot Scale score at follow-up evaluation (60 points) than those with no active litigation (87 points) (P=0.04) [48]. In another group of 50 patients who had ankle arthrodesis, complications occurred in 14 of 22 (64%) patients treated with external fixation and in six of 28 (21%) patients treated with screw fixation, but outcome scores at average 7.4 years after surgery were independent of fixation method used [49]. Anatomic dissection of ten cadaver specimens in which tibiotalocalcaneal arthrodesis was done with a 12-mm straight intramedullary nail revealed entrapment of a small branch of the first branch of the lateral plantar nerve in one specimen; the closest structures to the nail were the lateral plantar artery and lateral plantar nerve [50]. Sensory examination with filaments in 22 patients who had this arthrodesis showed diminished protective sensation in four (18%) patients, but two of these patients had suffered numbness prior to surgery and none had developed an ulcer after surgery [50]. In another group of 29 patients who had tibiotalocalcaneal arthrodesis using an intramedullary locking nail, ten (34%) patients had major posterior wound healing problems attributed to immunosuppressive medications and previous hindfoot surgery, and six (21%) patients had minor wound drainage problems [51]. Despite these and other complications, 27 (93%) patients eventually had satisfactory fusions [51]. In 20 patients with complex ankle deformity, tibiotalocalcaneal arthrodesis using a modified 90° blade plate resulted in successful fusion in 18 (90%) patients [52]. There was no difference in outcome scores between these patients and another group of similar patients treated with below knee amputation [52].
Session 7: The ankle In a cadaver study of axially loaded unconstrained ankle specimens, intact specimens had little change in the path of coupled axial or coronal motion during plantarflexion–dorsiflexion [53]. In contrast, specimens modified by an unconstrained Waugh total ankle arthroplasty had statistically significant coupled rotation pathways during plantarflexion– 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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dorsiflexion, as well as significantly greater coupled axial and coronal rotation hysteresis than intact specimens [53]. In a clinical follow-up study at an average of 4.8 years after Agility total ankle arthroplasty, pain was absent in 46 (54%) of 85 ankles, mild in 25 (29.5%) ankles, and moderate in 14 (16.5%) ankles [54]. In 98 ankles reviewed radiographically, 19 (19%) cases of component migration (12 tibial and seven talar) were noted; delayed union or non-union of the syndesmosis fusion occurred in eight (67%) of the 12 cases of tibial component migration and in 37 (38%) of all 98 cases reviewed [54]. In cadaver ankles, a fracture malunion was made with fibular osteotomy (4.5–6 cm proximal to the ankle joint) and division of the deep deltoid ligament, anterior–inferior tibiofibular ligament, and interosseous membrane [55]. In the loaded ankles in neutral flexion, factors noted to result in increased ankle joint contact stresses at the mid-lateral and posterolateral talar dome included fibular shortening, lateral displacement, and external rotation [55]. In 329 cases of osteoblastoma, 41 (12.5%) involved the foot and ankle, including 16 (39%) in the hindfoot, 14 (34%) in the forefoot, eight (20%) in the ankle, and three (7%) in the midfoot [56]. There was a soft tissue mass in 25% of cases, aggressive tumour margins in 32% of cases, and three (7%) cases with sarcomatous change [56].
Session 8: Tarsal osteotomies and reconstructions In 12 patients (17 feet) with Charcot-Marie-Tooth disease, cavovarus deformity was reconstructed with Dwyer calcaneal osteotomy, first metatarsal dorsiflexion osteotomy, Jones extensor hallucis longus tendon transfer with first interphalangeal arthrodesis, plantar fasciotomy, peroneus longus to brevis transfer, and clawtoe correction [57]. At minimum 1-year follow-up evaluation, all 17 feet were satisfactory, 15 (88%) feet were plantigrade, and none of the feet had plantar keratosis [57]. In nine patients (ten feet) with pes cavus adductus varus resulting from residual clubfoot in six (60%) feet and Charcot-Marie-Tooth disease in four (40%) feet, an oblique talar neck osteotomy was done, with displacement of the talar head in adduction–flexion and tendon transfers (peroneus longus to brevis,
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tibialis anterior to peroneus tertius, and heel cord lengthening) [58]. All osteotomies consolidated within 10 weeks with a mean horizontal talocalcaneal angle of 20° and without limitation of hindfoot motion [58]. Bony alignment was evaluated using optimized stereoradiography with implanted radio-opaque markers in six loaded cadaver feet before and after medial sliding osteotomy of the calcaneal tuberosity or opening wedge calcaneal osteotomy 10 mm proximal to the calcaneocuboid joint [59]. Neither osteotomy improved medial arch height significantly, but both procedures decreased the amount of heel valgus, and the opening wedge osteotomy decreased forefoot abduction and peritalar subluxation [59]. In 15 patients with flexible flatfoot deformity resulting from stage II posterior tibial tendon insufficiency, surgical treatment consisted of subtalar arthrodesis with flexor digitorum longus tendon transfer to the navicular [60]. At follow-up evaluation 27 months after surgery, correction of the preoperative hindfoot valgus deformity, forefoot abduction position, and longitudinal arch height was noted, with improvements in the average lateral talocalcaneal angle, anteroposterior and lateral talofirst metatarsal angles, talonavicular coverage angle, and medial cuneiform-to-floor distance [60]. In 28 feet with posterior heel pain, treatment consisted of excision of a Haglund deformity and retrocalcaneal bursectomy alone (13 (46%) feet) or combined with excision of intratendinous calcification and repair of the Achilles tendon insertion (15 (54%) feet) [61]. Average time to maximal symptomatic resolution was longer in patients with tendon calcification at the insertion (11.4 months) than those without (6.4 months); at minimum 2 years after surgery, percentage of satisfied patients was lower in patients with tendon calcification (79% feet) than those without (93% feet) [61].
Session 9: The ankle: soft tissue pathology In 86 patients with persistent lateral ankle and hindfoot pain for more than 3 months following a twisting injury, evaluation with history, physical examination, and diagnostic studies revealed the following nine diagnoses: (1) calcaneonavicular coalition in 27 (31%) of the 86 cases; (2) subtalar coalition in 17 (20%); (3) anterior process calcaneal
fracture in 12 (14%); (4) reflex sympathetic dystrophy in eight (9%); (5) avulsion fracture of anterior talofibular ligament in six (7%); (6) os trigonum in six (7%); (7) subtalar joint degenerative arthritis in five (6%); (8) peroneal tenosynovitis in four (5%); and (9) tibial degenerative cyst in one (1%) [62]. In 32 (37%) of these patients who underwent diagnosisspecific surgery, 22 (71%) had good or excellent results [62]. In 61 patients who had primary ankle lateral ligament reconstruction for chronic instability, associated conditions noted at surgery included: peroneal tenosynovitis in 47 (77%) patients, lateral gutter impingement lesion in 41 (67%), attenuated or torn peroneal retinaculum with peroneal subluxation in 33 (54%), ankle synovitis in 30 (49%), partial peroneus brevis tear in 15 (25%), osteochondral lesion of the talus in 14 (23%), accessory peroneus quartus muscle in five (8%), and tenosynovitis of a medial ankle tendon in three (5%) [63]. All patients had at least one associated condition [63]. In 31 ankles with chronic instability, lateral ligament reconstruction was done using a tendon stripper to harvest a split-thickness peroneus brevis tendon graft, and bone anchors to secure the graft [64]. At average 43 months after surgery, functional results were rated excellent in 20 (65%) ankles, good in nine (29%), fair in one (3%), and poor in one (3%), and ankle stability was achieved in all ankles except one with continued giving way in a patient with generalized ligamentous laxity [64]. A review of over 400 ankle MRI scans revealed previous lateral ligament damage in 66 (16%) cases, posterior tibial tendon abnormalities in 52 (12.5%) cases, peroneal tendon pathology in 42 (10%) cases, and osteochondral lesions of the talar dome in 18 (4.5%) cases [65]. Nine (50%) of the osteochondral lesions were associated with previous lateral ligament injury, and the other nine (50%) cases had no lateral ligament abnormality or evidence of traumatic etiology [65]. In 13 patients (13 ankles) who had superior peroneal retinaculum reconstruction for symptomatic peroneal tendon subluxation (seven (54%) cases) or dislocation (six (46%) cases), control of tendon subluxation and dislocation was achieved in 11 (85%) patients [66]. However, only seven (54%) patients had relief of pain and six (46%) patients had residual pain and tenderness [66]. 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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Session 10: Neuropathy and diabetes In 35 patients with painful peripheral neuropathy resulting from diabetes in 30 (86%) patients and other conditions in five (14%) patients, mexiletine (starting dose, 150 mg p.o. t.i.d.; taper after 2–3 months) was used for treatment of pain (after cardiac screening) [67]. Two (6%) patients stopped the drug because of nausea, but the other 33 (94%) patients had average 50% pain relief on the verbal analogue pain scale [67]. In 180 midfoot (type I) Charcot feet, retrospective review showed that the Eichenholtz stage at presentation was stage 0 (acute) in eight (4%) feet, stage I (fragmentation) in 27 (15%) feet, stage II (coalescence) in 50 (28%) feet, and stage III (consolidation) in 95 (53%) feet [68]. Treatment included total contact casts, removable walking boots, custom-molded orthoses, in-depth shoewear, and, if infection was present, debridement and antibiotics [68]. Ulceration did not occur in 113 (63%) patients; in 67 (37%) patients who developed ulceration, 13 (19%) patients required exostectomy, 28 (42%) patients had recurrent ulceration, and other surgery performed included arthrodesis in four patients, repeat exostectomy in two patients, below knee amputation in two patients, and Syme amputation in one patient [68]. In 34 patients with diabetic foot ulcers, the radionuclide bone scan was markedly positive in 22 (65%), moderately positive in eight (23%), and negative in four (12%) patients [69]. In the 22 patients with markedly positive scans, eight (36%) patients were treated with partial or complete amputation, and 14 (64%) patients were treated with local wound care and intravenous antibiotics [69]. A four-part study of rocker-bottom deformity was presented with the Roger Mann Award [70]. (1) Part 1: classification of 131 feet (109 patients) with rocker-bottom deformity based on anatomic location of deformity was type I (Lisfranc joints) in 43 (33%) feet, type II (naviculocuneiform and metatarsocuboid joints) in 60 (46%) feet, type III (perinavicular region) in 17 (13%) feet, and type IV (transverse tarsal joints) in 11 (8%) feet [70]. (2) Part 2: mechanical testing in a midfoot fixation model, consisting of eight matched pairs of cadaver specimens, showed that plantar plate fixation of the midfoot had significantly greater stiffness and loadto-failure than screw fixation [70]. 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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(3) Part 3: using a medial and lateral, plantar, submuscular operative approach developed with cadaver specimens, 34 diabetic patients (38 rockerbottom feet) were treated with plantar wedge osteotomy, with plantar plate fixation in 34 (89%) feet. At 1–4 years after surgery, all feet were clinically stable, and there were no amputations [70]. (4) Part 4: clinical review of 131 rocker-bottom feet, managed with a treatment algorithm based on the anatomic classification of deformity, showed 90% of patients satisfied with results of treatment [70]. In 26 feet (23 patients) with neuropathic ulceration under the first metatarsophalangeal joint, 17 (65%) feet healed after one operation, one (4%) foot healed after more than one operation, seven (27%) feet failed to heal and required amputation, and one (4%) foot required early amputation for deep infection [71]. Healing occurred with all nine (35%) ulcers classified as grade 2 or lower; with the 17 (65%) grade 3 ulcers, amputation was required for eight (47%) ulcers [71]. In 52 diabetic patients who had surgical treatment for an ankle fracture, eight (15%) patients had postoperative complications [72]. Patients with peripheral vascular disease and peripheral neuropathy were at increased risk for complications, which included five deep infections, two superficial infections, three cases of Charcot arthropathy, and one below knee amputation [72].
Poster presentations In five patients with persistent posterior ankle pain, the diagnosis of painful os trigonum syndrome was confirmed with a fluoroscopically-guided injection of 0.5–1 ml of lidocaine (1%) in the region of the trigonal synchondrosis, after injection of contrast agent to confirm correct location [73]. After surgical excision of the os trigonum, four (80%) patients had complete resolution of symptoms [73]. At a mean 19 months after Achilles tendon augmentation using flexor hallucis longus tendon with primary repair or debridement for Achilles tendon rupture (seven patients) or tendinosis (two patients), plantarflexion torque deficit on the operated extremity was 20% at 120° s−1 and 26% at 30° s−1 [74]. A 20% increase in hallux metatarsophalangeal joint dorsiflexion was noted on the operated side compared with the opposite side [74].
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In 15 matched pairs of preserved cadaver feet, osteotomy of the posterior calcaneal tuberosity (simulated avulsion fracture) was fixed with two 4.5 mm partially-threaded cannulated cancellous screws with washers [75]. Load-to-failure testing showed greater mean peak force at failure with two crossed screws (411 N) than with two laterally-placed parallel screws (262 N) (P<0.05) [75]. A survey of 100 diabetic patients showed that 37% patients had a history of foot problems, but 59% patients had never had their feet examined by their physician [76]. Self-examination of the feet was done daily by 36%, weekly or monthly by 39%, and never by 17% patients [76]. Examination showed that the shoes on 59 feet of 31 patients were too narrow across the metatarsal heads [76]. In ten embalmed cadaver feet, the origin of the medial sesamoid ligament was identified as a long, thin ellipse parallel to and slightly posterior to the shortest line connecting the dorsal and plantar articular margins of the first metatarsal head, 38% of the distance from dorsal to plantar sides [77]. In 20 subjects with hallux valgus deformity, dynamic hallux flexion angle (determined using a load cell) was compared with hallux valgus angle (from the anteroposterior radiograph) [78]. The correlation between these two quantities was weak, suggesting that factors other than the hallux valgus angle may contribute to the helical flexor mechanics with this deformity [78]. Ultrasonography was used to measure the distance between the lesser metatarsal heads and an acrylic board on which subjects stood with both feet [79]. The second, third, fourth, or fifth metatarsal heads associated with intractable plantar keratosis were significantly closer to the weightbearing surface than the respective metatarsal heads without a keratosis [79]. Fractures of both the posteromedial and lateral processes of the talus were noted in two patients after pronation–dorsiflexion injury [80]. In one patient, both fractures were internally fixed; in the other patient, the lateral process was fixed and the posteromedial process was excised. The fractures healed, and there was no limitation of activity at 18 months after surgery [80]. Autogenous saphenous vein graft wrapping of the tibial nerve and its branches was done in a patient with recurrent tarsal tunnel syndrome [81]. At a
subsequent operation, external scarring to the graft was noted, and the endothelial surface was directly adherent to the nerve [81]. Histologic examination showed no intervening mobile space between the nerve and vein graft, and neither neovascularization nor inflammatory reaction was evident [81]. Plantar pressure measurements in asymptomatic volunteers showed differences between the first step after a standing start and steps taken during a 6meter walk [82]. The first step was not representative of the steady state gait pattern, because the first step footprint was longer, more variable, had earlier midfoot contact, and had lower hindfoot pressures, compared with steps during the 6-meter walk [82]. Capsular distension by intra-articular injection of saline was shown to cause the ankle to adopt a position of 15–20° plantarflexion [83]. This observation may be helpful in confirming intraarticular placement of saline injected prior to arthroscopy [83].
Keynote addresses At the presidential symposium, invited speaker Ronald Quirk, MD, discussed navicular stress fractures [84]. The treatment regimen of nonweightbearing in a short leg cast for 6 weeks was noted to result in a union in 90% of patients, and a bone graft was suggested for management of nonunion [84]. Outgoing president G. James Sammarco, MD, reviewed the achievements of the AOFAS during the previous year, including the tremendous growth in membership of the Society and involvement of orthopaedic foot and ankle surgeons from around the world [85]. He thanked the members of the AOFAS for their support [85]. Incoming president James A. Nunley, MD, discussed the challenges of the future [86]. He emphasized that the spirit of camaraderie and friendship remains a great strength of the AOFAS [86].
Conclusion The social events, commercial exhibits, and breaks between sessions provided plenty of opportunity for registrants to discuss the scientific programme, review cases of interest, and renew contact with 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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colleagues. The meeting was a great success, thanks to the hard work of the AOFAS staff. The next meeting of the AOFAS will be on Specialty Day, 22 March 1998, at the meeting of the American Academy of Orthopaedic Surgeons in New Orleans, Louisiana, USA. The next summer meeting of the AOFAS will be held 24–26 July 1998, in Boston, Massachusetts, USA.
References 1 Saltzman CL, Deland JT, Kitaoka HB et al. Pre-meeting instructional course. Controversies in orthopaedics: the application of statistics to outcomes. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 2 Dorey F, Amstutz HC. Discrepancies in the orthopaedic literature: why? A statistical explanation. In: Heckman JD, Ed. Instructional Course Lectures, Vol. 42. Rosemont, IL: American Academy of Orthopaedic Surgeons, 1993: 555–564. 3 Dorey F, Nasser S, Amstutz H. Current concepts review: the need for confidence intervals in the presentation of orthopaedic data. J Bone Joint Surg 1993; 75A: 1844–1852. 4 Ebramzadeh E, McKellop H, Dorey F et al. Challenging the validity of conclusions based on P-values alone: a critique of contemporary clinical research and design methods. In: Schafer M, Ed. Instructional Course Lectures, Vol. 43. Rosemont, IL: American Academy of Orthopaedic Surgeons, 1994: 587–598. 5 Deland JT, Dorey F. Fireside chat – biostatistics: questions and answers. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 17. 6 Ouzounian T, Pedowitz WJ. Symposium – Decoding the CPT code confusion. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 18. 7 Ouzounian T, Pedowitz WJ. Fireside chat – CPT coding: questions and answers. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 33. 8 Gill LH. Imaging strategies, diagnostic studies, physical findings, and the timing of surgery. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 9 Yodlowski ML. Management of tarsal tunnel impingement, plantar intrinsic fibrosis and claw toes. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 10 Romash MM. Indications and technique for lateral wall decompression and peroneal tendon decompression. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 11 Richardson EG. Salvage calcaneal osteotomies and ostectomies. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 12 Fitzgibbons TC. Selected arthrodesis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 5. 13 Shereff MJ. The role of imaging and arthroscopy on evaluating ankle injuries. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34. 1997 Blackwell Science Ltd, Foot and Ankle Surgery, 3, 147–157
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14 Scranton PE. Lower extremity stress fractures: clinical diagnosis, differential, imaging and management. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34. 15 Clanton TO. Occult hindfoot fractures in the athlete. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34. 16 Bowman MW. Repair and aggressive rehabilitation of the ruptured Achilles tendon. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34. 17 Smith RW. Management of severe acute ankle sprains. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34. 18 Smith RW. Defining the flat foot: soft tissue – dynamic and static abnormalities. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 47. 19 Alexander IJ. Orthotic devices: biomechanically sound, or shams? The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 47. 20 Sangeorzan BJ. Surgical reconstruction alternatives: techniques with arthrodesis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 47. 21 Myerson MS. Surgical reconstruction alternatives: techniques with osteotomy. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 47. 22 Hansen ST. Reconstruction failures: how to avoid and salvage. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 47. 23 Atkins RM, Allen P, Livingston JA. Outcome following open reduction and internal fixation of intra-articular calcaneum fractures. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 6. 24 Abidi NA, Conti SF, Dhawan S. Factors related to poor wound healing after open reduction and internal fixation of calcaneal fractures. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 9–10. 25 Hufner T, Thermann H, Schratt H-E. Treatment of juvenile os calcis fracture: a long-term follow-up. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 6–7. 26 Coughlin MJ. Outcome of calcaneal fractures in the industrial patient. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 7–8. 27 Mulier T, Thienpont E, Dereymaeker G, Steenwerckx A. Severe Lisfranc injuries: primary arthrodesis or ORIF? The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 8–9. 28 Fehrle M, Saltzman CL, Cooper RR. Average 28 and 49 years follow-up of the same patient cohort after triple arthrodesis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 10. 29 Rippstein P, Jung M. Long-term outcome of triple arthrodesis, especially in respect to the ankle joint. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 12–13. 30 Thermann H, Schratt H-E, Hufner T et al. Long-term results of subtalar fusions after operative or conservative treatment of os calcis fractures. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 11.
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31 Luber MJ, Nunley JA. How to reduce the cost of hindfoot fusions. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 11–12. 32 Fortin PT, Grant AM. Limited midfoot fusion with calcaneal osteotomy for adult flatfoot. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 13. 33 Cooper PS, Posteraro AF, Nowak MD. Biomechanical analysis of the low tibiotalar (supramalleolar) osteotomy for ankle arthrosis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 14. 34 Pietropaoli MP, Wnorowski DC, Werner FW et al. Intramedullary screw fixation of Jones’ fractures: a biomechanical study. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 15. 35 Bozareth R, Crosby LA. Comparison of chevron osteotomies with and without fixation. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 15–16. 36 Winson IG, Lundberg A, Ahl T. Ranges of motion in the foot and ankle. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 16. 37 Winson IG, Lundberg A. The mid-tarsal joint – the relationships of the axes of motion. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 17. 38 Scranton PE, McDermott JE. Pathologic anatomic variations in the subtalar joint. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 18. 39 Usami N, Inokuchi S, Hiraishi E. Pathophysiology and treatment of subtalar instability. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 18–19. 40 Lamdan R, Johnson JE, Harris G et al. Hindfoot coronal alignment: a modified radiographic method. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 19–20. 41 Kumai T, Takakura Y, Akiyama K et al. Histopathological study of non-osseous tarsal coalition. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 20–21. 42 Kitaoka HB, Kura H, Westreich AJ et al. Animation of threedimensional tarsal bone position in flatfoot and normal foot. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 21–22. 43 Kartalian G, Kelikian AS, Kodros SA. Biplanar chevron osteotomy for the treatment of hallux valgus: a review. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 22–23. 44 Campbell JT, Schon LC, Parks B et al. Biplanar proximal closing wedge osteotomy with plantar plate fixation for correction of metatarsus primus varus. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 24–25. 45 Mulier T, Thienpont E, Dereymaeker G et al. Results after cheilectomy in sporters with hallux rigidus. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 23. 46 Easley ME, Anderson RB, Davis WH. Intermediate to longterm follow-up of medial approach dorsal cheilectomy for
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hallux rigidus. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 24. Haddad SL, Sabbagh RC, Resch S et al. Correcting and stabilizing the cross-over second toe: a comparison of the medium term results of flexor to extenson tendon transfer and of extensor tendon transfer. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 25. Monroe MT, Beals TC, Manoli A. Patient outcome after ankle arthrodesis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 26. Thermann H, Schratt H-E, Hufner T et al. Long-term results after ankle fusion: a comparison of internal and external fixation technique. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 27. Stephenson KA, Kile TA, Graves SC. A standardized technique for retrograde nail insertion during intramedullary tibiotalocalcaneal arthrodesis: a combined clinical and cadaveric study. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 27–28. Sochacki MA, Fitzgibbons TC, McMullen ST. Complications of tibio-talar-calcaneal arthrodesis using an intramedullary locking nail. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 28. Tabor OB, Anderson RB, Davis WH. Functional outcome of salvage arthrodesis of the ankle. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 29. Michelson JD, Schmidt G, Mizel MS. Kinematics of an unconstrained total ankle arthroplasty: comparison to normal ankle motion. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 29–30. Saltzman CL, Pyevich M, Alvine FT. Total ankle arthroplasty: two- to eleven-year follow-up of a unique design. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 30–31. Thordarson DB, Motamed S, Hedman TP. Effect of fibular malreduction of ankle contact stress in a PLR malunion model. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 31–32. Temple HT, Mizel MS, Murphy MD et al. Osteoblastoma of the foot and ankle. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 32–33. Watson AD, Anderson RB, Davis WH. Surgical treatment of cavovarus foot deformity in Charcot-Marie-Tooth disease in adults. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 34–35. Klaue K. Talus re-orientation osteotomy for treating pes cavus adductus-varus. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 35. Dyson E, Granberry W, Kamaric E et al. In vitro structural analysis of calcaneal osteotomies for acquired pes planus. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 35–36. Cohen BE, DiGiovanni BF, Johnson JE. Subtalar arthrodesis with flexor digitorum longus transfer for treatment of posterior tibial tendon insufficiency. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 36–37.
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61 Watson AD, Anderson RB, Davis WH. Comparison of results of surgical treatment of Haglund’s deformity with and without calcific insertional Achilles tendinitis. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 37–38. 62 Ouzounian T. Surgical management of persistent lateral ankle and hindfoot pain. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 38–39. 63 DiGiovanni BF, Fraga CJ, Cohen BE et al. Associated injuries found in chronic lateral ankle instability. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 39–40. 64 Sammarco GJ, Idusuyi OB. Reconstruction of the lateral ankle ligaments using a split peroneus brevis tendon graft. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 40–41. 65 Hepple S, Winson IG, Glew D. Lateral ligament injuries and osteochondral lesions in magnetic resonance imaging of the ankle. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 41. 66 Lonergan R, Davis WH, Anderson RB et al. Isolated superior peroneal retinaculum reconstruction for symptomatic peroneal tendon instability. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 41–42. 67 Vander Griend RA. Follow-up on the use of mexiletine for the treatment of painful neuropathy. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 42–43. 68 Krause JO, Brodsky JW. The natural history of type I midfoot neuropathic feet. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 43. 69 Jay PR, Michelson JD, Mizel MS. The efficacy of bone scans in evaluating diabetic foot ulcers: a retrospective study. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 44. 70 Schon LC, Weinfeld SB, Horton GA et al. Assessment and management of the rocker-bottom foot. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 44–45. 71 Brodsky JW, Hong TF. Surgical treatment of neuropathic ulcerations under the first metatarsal head. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 45–46. 72 Costigan WB, Thordarson DB. Surgical management of ankle fractures in diabetics. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 46–47. 73 Jones D, Saltzman CL, El-Khoury G. The diagnosis of the os trigonum syndrome with a fluoroscopically controlled injection of local anesthetic (poster). The American Orthopaedic Foot and
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Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 106. Monroe MT, Beals TC, Manoli A et al. Functional and dynamic assessment of plantarflexion peak torque following flexor hallucis longus augmentation for Achilles tendinosis or rupture (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 107. Pietropaoli MP, Wnorowski DC, Werner FW et al. Posterior tuberosity calcaneal avulsion fractures: a biomechanical study of two methods of fixation (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 108. Reveal GT, Laughlin RT, Reeve FM et al. Diabetic footwear survey (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 109. Guyton GP, Saltzman CL. Origin of the medial sesamoid ligament (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 110. Talbot KD, Saltzman CL, Brown TD. Hallucal flexor force change in hallux valgus (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 111. Samoto N, Sugimoto K, Takakura Y. Ultrasonographic evaluation of intractable plantar keratosis on weight bearing (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 112. Samoto N, Sugimoto K, Takakura Y. Fracture of both the posteromedial process and the lateral process of the talus (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 113. Campbell JT, Schon LC, Burkhardt LD. Histopathologic findings in autogenous saphenous vein graft wrapping for recurrent tarsal tunnel syndrome: a case report (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 114. Kelly AJ, Hillard PJ, Winson IG. Foot pressure measurement: is the first step enough? (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 115. Wainwright A, Kelly AJ, Winson IG. A new physical sign in ankle arthroscopy (poster). The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 116. Quirk R. Presidential symposium – management of the fractured navicular. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 22. Sammarco GJ. Outgoing presidential address. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 26. Nunley JA. Incoming presidential address. The American Orthopaedic Foot and Ankle Society, Thirteenth Annual Summer Meeting, Final Program 1997; 13: 26.