Changes in gait associated with acute stage II posterior tibial tendon dysfunction.

The purpose of this study was to examine differences in gait mechanics between patients with acute stage II PTTD and healthy volunteers. Hindfoot and midfoot kinematics, plantar foot pressures and electromyographic (EMG) activity of the posterior tibialis, gastrocnemius, anterior tibialis and the peroneals were measured in five patients with acute stage II PTTD. Kinematics and kinetics were compared to a database of 20 healthy volunteers. EMG and plantar pressure data were obtained from five healthy volunteers. Hindfoot moments and powers were also calculated. The center of pressure excursion index (CPEI) was calculated from the plantar pressures. Significant differences were observed between the two groups, which confirmed clinical observations. Limited hindfoot eversion and increased midfoot external rotation occurred during the first and third rockers. The EMG data suggested that tendon dysfunction in the posterior tibialis is associated with compensatory activity, not only in its antagonists (the peroneals), but also in the anterior tibialis and the gastrocnemius. These data suggest that non-operative treatment of patients with PTTD should consider minimizing the activity of the posterior tibialis as well as the peroneals, the anterior tibialis and the gastrocnemius.

Mechanical behavior of the Lisfranc and dorsal cuneometatarsal ligaments: in vitro biomechanical study.

OBJECTIVES: To define the anatomy and mechanical properties of two ligaments stabilizing the medial tarsometatarsal joints: the Lisfranc ligament and the dorsal cuneometatarsal ligament. DESIGN: Cadaveric study in normal feet. SETTING: Biomechanics laboratory. PATIENTS OR PARTICIPANTS: Twelve fresh-frozen cadaveric feet were studied. INTERVENTION: The Lisfranc and dorsal cuneometatarsal ligaments were dissected, dimensions measured, and material properties determined with a servohydraulic MTS machine on bone-ligament-bone preparations. MAIN OUTCOME MEASUREMENTS: Stiffness, strain, stress, modulus, failure load, ligament length, width, thickness, and cross-sectional area were determined. RESULTS: Dorsal ligament stiffness was 66.3+/-18.3 newtons per millimeter and the Lisfranc ligament stiffness was 189.7+/-57.2 newtons per millimeter. The failure load of the dorsal ligament averaged 150.7+/-33.1 newtons and for the Lisfranc ligament, 368.8+/-126.8 newtons. CONCLUSIONS: The stiffness and load to failure of the dorsal cuneometatarsal ligament were much higher than anticipated, which indicates that it contributes significantly to stabilizing the second metatarsal to the first cuneiform.

Calcaneocuboid distraction arthrodesis for posterior tibial tendon dysfunction and flatfoot: a cadaveric study.

Nine fresh-frozen foot specimens were studied to determine the mechanical behavior of the foot using calcaneocuboid distraction arthrodesis, an operation designed for treatment of posterior tibial tendon dysfunction with flatfoot deformity. Flatfoot deformity was created in cadaveric specimens, and to simulate toe-off phase of gait, loads were applied to the plantar surface of the foot and six tendons. Three-dimensional tarsal bone positions were determined with a magnetic tracking system. With ligament sectioning, flatfoot deformity was observed and average arch height decreased 53 +/- 3.5 mm. Height arch increased after calcaneocuboid distraction arthrodesis an average of 3.2 +/- 3.6 mm and was less than normal arch at an average of 2.1 +/- 2.4 mm. Metatarsotalar alignment compared with flatfoot improved after calcaneocuboid distraction arthrodesis in adduction and inversion to the extent that these were not significantly different from intact foot positions. Calcaneotalar position improved after calcaneocuboid distraction arthrodesis in adduction and inversion. Calcaneocuboid alignment compared with flatfoot improved after calcaneocuboid distraction arthrodesis in adduction, plantar flexion, and eversion, but compared with an intact foot was overcorrected in all three planes of motion. Arch alignment in simulated toe-off phase of gait in cadaveric feet was improved significantly with calcaneocuboid distraction arthrodesis but was not reduced anatomically.

The manual stress test may not be sufficient to differentiate ankle ligament injuries.

OBJECTIVE: To assess the accuracy of stress tests (anterior drawer, talar tilt) in the diagnosis of lateral ligament injuries.Design. Stress tests were performed in vitro, and rotation and displacement of the calcaneus relative to the tibia were measured. BACKGROUND: Stress tests are commonly used to diagnose ankle injuries. However, it is controversial as to whether stress tests can accurately differentiate between isolated anterior talofibular ligament injuries and combined anterior talofibular and calcaneofibular ligament injuries. METHODS: Stress tests were performed in vitro under three conditions with both ligaments intact, after sectioning the anterior talofibular ligament, and after sectioning the anterior talofibular and calcaneofibular ligament. Motion of the calcaneus relative to the tibia was measured in neutral and in 20 degrees of plantarflexion at the ankle. RESULTS: There were statistically significant differences among cadavers, examiners and positions. There was a difference between isolated anterior talofibular ligament sectioning and combined anterior talofibular and calcaneofibular ligament sectioning in lateral tilt but not in anterior displacement. In contrast, a difference was found between intact and anterior talofibular ligament sectioned specimens in anterior displacement but not in lateral tilt. However the differences were not great enough to differentiate between the two conditions. CONCLUSIONS: Each of the stress tests provides reasonable hindfoot displacement but neither is sufficient for accurate diagnosis of specific ligament involvement due to the large amount of individual variation. RELEVANCE: Many clinicians rely on stress tests to diagnose lateral ligament injuries and to assess the extent of anatomic disruption. This in vitro study has demonstrated poor correlation between clinical stress tests and the degree of ligamentous disruption.

Role of medical capsule and transverse metatarsal ligament in hallux valgus deformity.

The role of the medial capsule and transverse metatarsal ligament in hallux valgus deformity including stability of the first metatarsophalangeal and adjacent joints was investigated in vitro. The three-dimensional positions of the proximal phalanx, first metatarsal, and second metatarsal before and after sectioning the medial capsule and metatarsal ligament were measured using a magnetic tracking system. Valgus deformity of the hallux increased with medial capsule sectioning an average of 22.3 degrees +/- 6 degrees. Valgus deformity of the hallux increased with medial capsule and metatarsal ligament sectioning an average of 27.4 degrees +/- 9.1 degrees. Valgus deformity of the hallux did not change significantly after sectioning the metatarsal ligament only. No significant changes were found in varus and eversion of the first metatarsal, in valgus of the second metatarsal, in the distance between first and second metatarsal heads after sectioning the medial capsule, or in the metatarsal ligament. This study shows the importance of the medial capsule in hallux valgus deformity. The transverse ligament did not contribute substantially to cause the deformity.

Three-dimensional analysis of flatfoot deformity: cadaver study.

Eleven fresh-frozen cadaver foot specimens were tested to define changes in tarsal alignment associated with flatfoot, or pes planus, a common clinical problem. The three-dimensional position of four bones (talus, calcaneus, navicular, and first metatarsal) relative to the fixed tibia was determined with a magnetic tracking system in the intact foot and flatfoot conditions. In the flatfoot, the average metatarsal-to-talar position difference was 11.7 degrees +/-4.4 degrees in abduction (P < 0.0001), 10.4 degrees +/-3.6 degrees in dorsiflexion (P < 0.0001), and 10.9 degrees +/-6.0 degrees in eversion (P < 0.0001) compared with the intact foot. The average calcaneal-to-talar position difference was 2.2 degrees +/-2.6 degrees in abduction (P=0.0171) and 2.7 degrees+/-2.0 degrees in eversion (P=0.0012) compared with the intact foot. The average navicular-to-talar position difference was 13.6 degrees +/-5.0 degrees in abduction (P < 0.0001), 10.5 degrees +/-6.6 degrees in dorsiflexion (P=0.0004), and 8.1 degrees +/-3.8 degrees in eversion (P < 0.0001) compared with normal. The average talar-to-tibial position difference was -8.2 degrees +/-3.2 degrees in dorsiflexion (P < 0.001) compared with the intact foot. The average arch height difference was 6.0+/-2.7 mm (P < 0.0001) less than the normal condition. The deformity associated with flatfoot is complex and occurs in multiple joints and in all three planes. An understanding of the normal and pathologic (flatfoot) conditions is necessary to surgically restore appropriate alignment and function in hindfoot reconstruction operations.

Oblique metatarsal osteotomy for intractable plantar keratosis: 10-year follow-up.

Twenty patients (14 women and 6 men) (23 feet) had a single oblique osteotomy operation of the 2nd, 3rd, or 4th metatarsal without fixation during an 8-year period. The mean age was 46 years (range, 21-64 years). Each patient had a painful intractable plantar keratosis preoperatively. The average follow-up was 10 years (range, 3-14 years). Postoperatively, reoperation was performed in four feet because of painful callosities. For 13 of the 19 feet that did not have reoperation, patients were limited in footwear or required a shoe insert. Overall results were good for 10 feet, fair for 7 feet, and poor for 6 feet. The only complication was a deep infection that occurred in one foot (good result). Nonunion occurred in one foot and delayed union in one. The average decrease in metatarsal length after osteotomy was 6+/-6 mm. The single oblique lesser metatarsal osteotomy may be successful, but one half of the patients continued to have some degree of pain and most patients had limitations in footwear. Overall results were disappointing, and patients who are offered this procedure should be advised of its limitations.

Chevron osteotomy of lesser metatarsals for intractable plantar callosities.

We performed distal chevron osteotomy of the second, third, or fourth metatarsal for painful plantar callosities in 19 non-rheumatoid patients (16 women, 3 men; 21 feet); their mean age was 59 years (32 to 85). The mean follow-up was four years (2 to 7). The overall results were good in 16 feet, fair in two, and poor in three, with four patients still having painful plantar callosities. There was union in all feet, but transfer metatarsalgia developed in three and three required an orthosis. Distal chevron osteotomy for intractable plantar callosities was successful both clinically and radiologically in most patients.

Peroneal tendon injuries.

Injury to the peroneal tendons is a frequently overlooked cause of persistent lateral ankle pain after trauma. Peroneal tendon anatomy, biomechanics, diagnostic studies, and traumatic disorders were reviewed.

Salvage treatment of failed hallux valgus operations with proximal first metatarsal osteotomy and distal soft-tissue reconstruction.

We reviewed the results of 15 patients (16 feet) in whom a hallux valgus procedure had failed. Salvage was by proximal crescentic first metatarsal osteotomy with distal soft-tissue reconstruction. Results based on a clinical scale considering the level of pain, activity limitations, support requirement, footwear limitations, and alignment were good in 11, fair in two, and poor in three. Patients were satisfied with the results in 10 feet, satisfied with reservations in four feet, and dissatisfied in two feet. Complications were: transfer metatarsalgia in three, hallux varus in one, and osteotomy nonunion in one. One of the patients required reoperation to bone graft a proximal osteotomy. Metatarsal osteotomy was helpful in the salvage treatment of recurrent, symptomatic hallux valgus when the first metatarsophalangeal joint was functional and painless.

Ankle arthrodesis in patients with rheumatoid arthritis.

The results of 26 ankle arthrodeses performed for rheumatoid arthritis on 21 patients were reviewed. Tibiotalar arthrodesis was performed in 14 ankles, and tibiotalocalcaneal arthrodesis was performed in 12. External fixation was used in 20 ankles, and internal fixation was used in six. Followup was available in 24 of 26 ankles (19 patients), and averaged 5 years (range, 2-8 years). There was no pain experienced in 19 ankles; mild, occasional pain was experienced in four ankles; and moderate, daily pain was experienced in one ankle. Daily activities were limited in five patients and recreational activities were limited in 11. All patients reported some difficulty walking on uneven terrain. Nearly all patients were satisfied; two were satisfied with reservations and two were dissatisfied. Union was achieved in 25 of 26 (96%) ankles. Ankle arthrodesis is an effective operation in patients with rheumatoid arthritis. Unlike previous reports, union and complication rates in this series were comparable with rates for arthrodesis for posttraumatic and degenerative arthritis.

Reconstruction operations for acquired flatfoot: biomechanical evaluation.

A major limitation of operations commonly performed for acquired flatfoot is inadequate correction of alignment. The authors defined the efficacy of two operations, deltoid ligament reconstruction and flexor digitorum longus tendon transfer, for treatment of posterior tibial tendon dysfunction with flatfoot deformity. Twelve fresh-frozen foot specimens were used. A flatfoot deformity was created, and, to simulate the midstance phase of gait, loads were applied axially to the plantar surface of the foot and to appropriate tendons. Foot position improved substantially after deltoid ligament reconstruction but not after flexor digitorum longus tendon transfer. The average increase in arch height after deltoid ligament reconstruction was 10.3 +/- 8.9 mm and after flexor digitorum longus tendon transfer, -0.6 +/- 2.0 mm. Mean arch height after deltoid ligament reconstruction was 2.2 +/- 1.7 mm less than intact arch height and, after flexor digitorum longus tendon transfer, 13.2 +/- 9.0 mm less than intact arch height. Improvement in metatarsal-talar, calcaneal-talar, and talar-tibial positions was significantly greater after deltoid ligament reconstruction than after flexor digitorum longus tendon transfer. Although the authors do not advocate clinical use, the deltoid ligament reconstruction was more effective than flexor digitorum longus tendon transfer in restoring arch alignment in flatfoot.

Arthrodesis versus resection arthroplasty for failed hallux valgus operations.

The results for 18 patients (20 feet) in whom a hallux valgus procedure had failed were reviewed. Ten patients (11 feet), with a mean age of 63 years, had correction with Keller resection arthroplasty and were observed for an average of 10 years (range, 3-15 years). The hallux valgus angle improved an average of 11 degrees +/- 3 degrees, and the intermetatarsal angle improved an average of 2 degrees +/- 1.7 degrees. Results were good in six feet, fair in four, and poor in one. Eight patients (nine feet), with a mean age of 63 years, had correction with arthrodesis and were observed for an average of 5 years (range, 2-8 years). The hallux valgus angle improved an average of 23 degrees +/- 6.9 degrees, and the intermetatarsal angle improved an average of 2 degrees +/- 3 degrees. Results were good in six feet, fair in two, and poor in one. There were differences between the two operations in terms of patient satisfaction, pain relief, appearance, and footwear. The incidence of metatarsalgia was similar for the two groups. Complications, particularly malalignment, were more common in the resection group. None of the patients required additional revision operation. Resection arthroplasty is a simple procedure and does not require cast immobilization. Resection arthroplasty and arthrodesis are reasonable options for salvage treatment of failed hallux valgus operations in older patients because good results were achieved in six of nine (67%) feet after arthrodesis and in six of 11 (54%) feet after resection.

Arthrodesis for the treatment of arthrosis of the ankle and osteonecrosis of the talus.

We evaluated the results of arthrodesis that had been performed for arthrosis of the ankle and osteonecrosis of the talus in nineteen patients. Twelve patients were men, and seven were women. The mean age of the patients was thirty-four years (range, nineteen to fifty-eight years). The median interval between the injury and the index operation was twenty-one months (range, six to 408 months). The arthrodesis was performed at the level of the ankle only in three patients and in both the ankle and the subtalar joint in sixteen. External fixation was used in thirteen patients, internal fixation was used in four, and no fixation was used in two. Supplemental bone graft from the iliac crest was used in fourteen patients, and local bone graft was used in five. The mean duration of follow-up was six years (range, two to fifteen years). The clinical result was excellent in seven patients, good in six, fair in three, and poor in three. Union was achieved in sixteen ankles, but it was delayed in one of them. Complications occurred in four patients: one had a tibial stress fracture, one had an infection at the site of a non-union, and two had malalignment in plantar flexion. Overall, the arthrodesis was successful in these patients. The use of rigid fixation and bone-grafting had a rate of success approximating that reported for primary arthrodesis in patients who do not have avascular necrosis.

Subtalar arthrodesis with internal compression for post-traumatic arthritis.

We studied retrospectively the results in 24 patients (25 feet) who had been treated by subtalar arthrodesis with internal compression for post-traumatic arthritis from 1988 to 1992. Fifteen patients were men (16 feet) and nine (9 feet) were women. Their mean age was 43 years (22 to 68), and the average duration of follow-up was four years (2 to 6). A single compression screw was used in all feet and iliac-crest bone grafting in ten. Union was achieved in 24 of the 25 feet (96%). Based on a clinical scale the results were excellent in 10 feet, good in 7, fair in 6, and poor in 2 and on the Angus and Cowell score they were good in 19 feet, fair in 4, and poor in 2. The two poor results were due to nonunion in one patient and reflex sympathetic dystrophy in the other. One reoperation was performed for nonunion. Eighteen patients (18 feet) were satisfied with the results, four were satisfied with reservations, and three were dissatisfied. Progressive ankle and midfoot arthritis did not occur in the absence of pre-existing degenerative changes in these joints. We conclude that isolated subtalar arthrodesis with internal compression was effective treatment for post-traumatic subtalar arthritis. Iliac-crest bone grafting was not routinely required.

Subtalar arthrodesis versus flexor digitorum longus tendon transfer for severe flatfoot deformity: an in vitro biomechanical analysis.

We defined the mechanical behavior of the foot after an operation for treatment of the flatfoot deformity, subtalar arthrodesis, and compared results with those from flexor digitorum longus tendon transfer. Twelve fresh-frozen human foot specimens were used. Supporting elements were sectioned to create a flatfoot deformity. To simulate midstance phase of gait, loads were applied axially to the plantar foot and to five tendons. Reduction of deformity in metatarsal-talar, calcaneal-talar, and talar-tibial positions was achieved and was significantly greater after subtalar arthrodesis operation than after flexor digitorum longus transfer.

Metatarsal lengthening: case report and review of literature.

Shortening of one or more metatarsals may be a cause of metatarsalgia and painful toe deformity. Usually, symptoms are limited and may be successfully addressed with nonoperative treatment. Rarely, operation indicated. This report reviews the surgical techniques, results, and complications. These operations include osteotomy and one-stage distraction with bone grafting, osteotomy and one-stage distraction without bone grafting, osteotomy with gradual distraction and bone grafting, and osteotomy with gradual distraction without bone grafting.

Subtalar joint stability. Talocalcaneal interosseous ligament function studied in cadaver specimens.

We used 6 fresh-frozen foot specimens to evaluate the contribution of the talocalcaneal interosseous ligament (IOL) in stabilizing the subtalar (talocalcaneal) joint. The tibia and ankle joint were secured, and the calcaneus was subjected to a bending and axial force applied circumferentially. The position of the calcaneus relative to the talus was monitored with a magnetic tracking system. Motion was recorded at every half degree in the 0 degree to 360 degrees arc before and after sectioning of the IOL. The results in the intact feet indicated that, with circumferential loading of the subtalar joint, there were two stable zones (supination stable zone, pronation stable zone) during which little displacement occurred and two transition zones during which the supination and pronation movement occurred. There was a greater degree of supination displacement after IOL sectioning (p = 0.008), but no pronation displacement. The IOL contributed substantially to subtalar joint stability, particularly in supination.

Effect of plantar fasciotomy on stability of arch of foot.

Five anatomic specimen feet were studied at three different loading levels to determine the three-dimensional position of the individual bones constituting the arch. Bone displacements were compared before and after plantar fasciotomy. Bone displacements changed to a greater extent with higher loads. With a 222-N load the greatest difference in position in dorsiflexion after fasciotomy occurred at the talar to tibial joint, followed by the metatarsal relative to navicular and navicular to talar joints. The greatest difference in displacement in eversion was at the metatarsal relative to navicular, followed by the navicular to talar and calcaneal to talar joints. The greatest difference in displacement in abduction was at the navicular to talar and then the calcaneal to talar joints. The observed displacement of all joints, with changes about all three axes, was consistent with the finding of flattening of the arch in previous reports on plantar fasciotomy. Thus, these data suggest that sectioning of the fascia, which sometimes is performed for fasciitis, may have an effect on the mechanical behavior of the arch.