Tibiofibular syndesmosis in asymptomatic ankles: initial kinematic analysis using four-dimensional CT.

AIM: To evaluate the reliability of ankle syndesmotic measurements and their changes during active motion using four-dimensional computed tomography (4DCT) examination in asymptomatic ankles. MATERIALS AND METHODS: 4DCT was performed on both ankles of patients with signs and symptoms of unilateral ankle instability. Ankles from the asymptomatic side of 10 consecutive patients were included in this analysis. Five ankle syndesmotic measurements were adopted from the available literature and performed by two fellowship-trained foot and ankle surgeons: (1) syndesmotic anterior distance (SAD); (2) syndesmotic posterior distance (SPD); (3) syndesmotic translation (ST); (4) syndesmotic tibiofibular angle (STFA); and (5) ankle tibiofibular angle (ATFA). A Monte Carlo simulation was also performed to obtain exact p-values with 99% confidence intervals. RESULTS: Excellent interobserver reliability was observed among the two readers for four out of five measurements (intra-class correlation coefficients [ICC]: 0.767-0.995, p<0.001-0.020). The ICC values for SAD were not statistically significant (ICC=0.548 and 0.569 for dorsi and plantarflexion respectively, p=0.1). Among the five measurements, only ST measurements had significant changes during active motion (median [interquartile range] for change: -0.70 mm [-1.6-0.10]; p=0.012). Of the above measurements, only the ST measurements demonstrated a negative linear association with the tibiocalcaneal angle during active motion (beta=-2.5, p=0.04). CONCLUSIONS: Reliable quantitative kinematic assessment of ankle syndesmosis can be performed using 4DCT examination. Syndesmotic measurements remain unchanged during ankle motion except for the syndesmotic translation, which tends to decrease during plantar flexion.

Clinical outcome after primary triple arthrodesis.

BACKGROUND: To analyze the effects of multiple preoperative, intraoperative, and postoperative factors on the intermediate results of triple arthrodesis, we focused on preoperative deformity, preoperative diagnosis, degree of clinical and radiographic correction, and arthritis of the ankle. METHODS: Between 1987 and 1995, 160 patients were managed with a total of 183 triple arthrodeses. Patients who had an infection or neuroarthropathy or who were managed with a revision arthrodesis were excluded from our study. Of the 160 patients, 111 (132 feet) who had been followed for a minimum of two years formed our study group. Each patient had an arthrodesis with rigid screw fixation and realignment of the joint surfaces without resection of wedges. The average duration of follow-up was 5.7 years (range, 2.0 to 10.8 years). RESULTS: As seen radiographically, arthritis of the ankle was significantly more severe postoperatively than preoperatively (p<0.01), although patient satisfaction was not associated with the presence of arthritis. On a scale (not a visual analog) of 0 (not satisfied) to 10 (completely satisfied), overall satisfaction averaged 8.3 points (range, 0 to 10 points). The postoperative modified ankle-hindfoot score of the American Orthopaedic Foot and Ankle Society averaged 60.7 points (range, 0 to 94 points). There was a significant association (p = 0.001) between satisfaction of the patient and postoperative alignment. Ten patients had a total of eleven complications: four superficial wound problems, three nonunions, one case of superficial peroneal neuritis, one case of Charcot-like neuroarthropathy of the foot (in a patient in whom diabetes developed during the follow-up period), one rupture of the Achilles tendon, and one case of peroneal tenosynovitis. Of the 111 patients, 101 (91 percent) stated that they would have the procedure again under similar circumstances, and this response was independent of the preoperative diagnostic or deformity group. CONCLUSIONS: Triple arthrodesis for the treatment of various deformities and etiologies is effective in relieving pain and improving functional deficits. Although a high prevalence of subsequent arthritis of the ankle was noted clinically and radiographically, we could detect no association between satisfaction of the patient and arthritis.

Isolated subtalar arthrodesis.

BACKGROUND: The purposes of this retrospective study were to review the results of isolated subtalar arthrodesis in adults and to identify factors influencing the union rate. The hypotheses were that (1) the overall outcome is acceptable but is not as favorable as previously reported, (2) complication rates, especially the nonunion rate, are higher than previously reported, and (3) factors contributing to a less favorable union rate can be identified. METHODS: Between January 1988 and July 1995, 184 consecutive isolated subtalar arthrodeses were performed in 174 adults (115 men and fifty-nine women) whose average age was forty-three years (range, eighteen to seventy-nine years). Eighty patients (46 percent) were smokers. The indications for the procedure included posttraumatic arthritis after a fracture of the calcaneus (109 feet), a fracture of the talus (thirteen feet), or a subtalar dislocation (thirteen feet); primary subtalar arthritis (thirteen feet); failure of a previous subtalar arthrodesis (twenty-eight feet); and residual congenital deformity (eight feet). Rigid internal fixation with one or two screws was used for all feet. Bone graft was used in 145 feet; the types of graft material included cancellous autograft (ninety-four feet), structural autograft (twenty-nine feet), cancellous allograft (seventeen feet), and structural allograft (five feet). Bone graft was not used in the remaining thirty-nine feet. RESULTS: Clinical and radiographic follow-up examinations were performed for 148 (80 percent) of the 184 feet at an average of fifty-one months (range, twenty-four to 130 months) postoperatively. The average ankle-hindfoot score according to the modified scale of the American Orthopaedic Foot and Ankle Society (maximum possible score, 94 points) improved from 24 points preoperatively to 70 points at follow-up. Thirty feet had clinical evidence of nonunion. The union rate was 84 percent (154 of 184) overall, 86 percent (134 of 156) after primary arthrodesis, and 71 percent (twenty of twenty-eight) after revision arthrodesis. The union rate was 92 percent (ninety-three of 101 feet) for nonsmokers and 73 percent (sixty-one of eighty-three feet) for smokers (p < 0.05). Intraoperative inspection revealed that 42 percent (seventy-eight) of the 184 feet had evidence of more than two millimeters of avascular bone at the subtalar joint; all thirty nonunions occurred in this group (p < 0.05). A nonunion occurred in three of the five feet that had been treated with structural allograft and in two of the six feet in which the subtalar arthrodesis had been performed adjacent to the site of a previous ankle arthrodesis. After elimination of the subgroups of feet in patients who smoked, those that had had a failure of a previous subtalar arthrodesis, those that had been treated with a structural graft, and those that had had the subtalar arthrodesis adjacent to the site of a previous ankle arthrodesis, the union rate improved to 96 percent (seventy-three of seventy-six). Complications other than nonunion included prominent hardware requiring screw removal (thirty-six of 184 feet; 20 percent), lateral impingement (fifteen of 148 feet; 10 percent), symptomatic valgus malalignment (five of 148 feet; 3 percent), symptomatic varus malalignment (four of 148 feet; 3 percent), and infection (five of 184 feet; 3 percent). CONCLUSIONS: To the best of our knowledge, the present study includes the largest reported series of isolated subtalar arthrodeses in adults. Our results suggest that the outcome following isolated subtalar arthrodesis is not as favorable as has been reported in previous studies. The rate of union was significantly diminished by smoking, the presence of more than two millimeters of avascular bone at the arthrodesis site, and the failure of a previous subtalar arthrodesis (p < 0.05 for all). Other factors that probably affect the union rate include the use of structural allograft and performance of the arthrodesis adjac

A comparative mechanical analysis of the pointe shoe toe box. An in vitro study.

Dancing en pointe requires the ballerina to stand on her toes, which are protected only by the pointe shoe toe box. This protection diminishes when the toe box loses its structural integrity. The objectives of this study were 1) to quantify the comparative structural static and fatigue properties of the pointe shoe toe box, and 2) to evaluate the preferred shoe characteristics as determined by a survey of local dancers. Five different pointe shoes (Capezio, Freed, Gaynor Minden, Leo's, and Grishko) were evaluated to quantify the static stiffness, static strength, and fatigue properties (cycles to failure) of the shoes. Under axial loading conditions, the Leo's shoe demonstrated the highest stiffness level, and the Freed shoe exhibited the least strength. Under vertical loading conditions, the Leo's and Freed shoes demonstrated the highest stiffness levels, and the Gaynor Minden and Freed shoes exhibited the highest strength. Fatigue testing highlighted the greatest differences among the five shoes, with the Gaynor Minden demonstrating the highest fatigue life. Dancers rated the top five shoe characteristics, in order of importance, as fit, comfort, box/platform shape, vamp shape, and durability and indicated that the "best" shoe is one that "feels right" and permits artistic maneuvers, not necessarily the strongest or most durable shoe.

Avascular necrosis of the talus treated by core decompression.

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.

Subtalar distraction bone block arthrodesis.

This retrospective study analyses the results of subtalar bone block distraction arthrodesis used in the treatment of late complications of calcaneal fractures, acute severely comminuted fractures, nonunion (and malunion) of attempted subtalar arthrodeses, avascular necrosis of the talus, and club-foot deformity. Of 39 patients (41 feet) who had this procedure, 35 (37 feet) returned for follow-up after a mean of 70 months (26 to 140). There were 24 men (25 feet) and 11 women (12 feet) with a mean age of 41 years (16 to 63). Each completed a standardised questionnaire, based on the hindfoot-scoring system of the American Orthopaedic Foot and Ankle Society and were reviewed both clinically and radiologically. Of the 37 operations, 32 (87%) achieved union. The mean hindfoot score (maximum of 94 points) increased from 21.1 points (8 to 46) preoperatively to 68.9 (14 to 82) at the final follow-up. The mean talocalcaneal and calcaneal pitch angles were 20.5 degrees and 4.9 degrees before operation, 25.9 degrees and 8.3 degrees immediately after, and 24.6 degrees and 7.7 degrees at the final follow-up, respectively. The mean talar declination angle improved from 6.5 degrees (-10 to 22) before operation to 24.8 degrees (14 to 32) at the final follow-up. The mean talocalcaneal height increased from 68.7 mm before operation to 74.5 mm immediately after and 73.5 mm at the final follow-up. Of the 37 arthrodeses available for review, 32 were successful; 29 patients (30 arthrodeses) were satisfied with the procedure. Minimal loss of hindfoot alignment occurred when comparing radiographs taken immediately after operation and at final follow-up.

Nerve entrapment, neuropathy, and nerve dysfunction in athletes.

Nerve entrapment, neuropathy, and nerve dysfunction in the legs, ankles, and feet of athletes are not uncommon conditions. Frequently, the conditions are overlooked as the more obvious musculoskeletal injury draws the physician's attention. Typically, with conservative treatment, including an occasional injection of local anesthetic with and without corticosteroid, resolution is achieved. Rarely, symptoms are severe and diffuse enough to require administration of a tricyclic antidepressant medication to decrease the nerve irritability. In cases that fail to respond to conservative treatment and have well-localized neurologic findings, surgery may be indicated. During surgery, the nerve should be minimally manipulated. The surrounding veins, arteries, and fat should be relatively undisturbed. Critical to understanding and treating these problems is a thorough knowledge of the peripheral neuroanatomy.

The management of neuroarthropathic fracture-dislocations in the diabetic patient.

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.

Neuropathies of the foot and ankle in athletes.

Although neuropathies in the athlete's foot and ankle are uncommon, they are often underdiagnosed. This is primarily due to the complex interplay of factors that are required for their presentation. The most frequently encountered entrapment syndromes (in decreasing order) involve the interdigital nerves, first branch of the lateral plantar nerve, isolated medial or lateral plantar nerves, posterior tibial nerve, deep peroneal nerve, superficial peroneal nerve, sural nerve, and saphenous nerve. A thorough knowledge of peripheral nerve anatomy is essential in establishing the diagnosis. Roentgenograms may reveal bony abnormalities that are the diagnosis. Roentgenograms may reveal bony abnormalities that are commonly contributory. Electrodiagnostic tests may be normal because these dynamic syndromes often resolve at rest. In most cases, correction of underlying etiologies combined with rest, NSAIDs, and occasionally injections will allow resolution of the syndrome. Recalcitrant cases may require surgical decompression, which frequently provides satisfactory results.

Dance screen programs and development of dance clinics.

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.

Branches of the tibial nerve: anatomic variations.

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.

Posttraumatic posterior tibialis tendon insertional elongation with functional incompetency: a case report.

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.

Peripheral nerve vein wrapping for intractable lower extremity pain.

HYPOTHESIS/PURPOSE: The purpose of this study was to determine the effectiveness of lower extremity peripheral nerve vein wrapping procedures in the management of patients with intractable lower extremity pain. The hypothesis was that nerve insulation through vein wrapping is effective in treating symptoms related to adhesive neuralgia, but not those secondary to intraneural damage. METHODS: We retrospectively reviewed 25 consecutive patients whose intractable chronic lower extremity peripheral neuralgia had been treated with revision neurolysis and vein wrapping. The 14 women and 11 men had an average age of 39 years (range, 21 to 53 years). Vein wrapping was performed using a saphenous vein autograft in 19 patients and a fetal umbilical vein in six patients. The average length of follow-up after vein wrapping was 24 months (range, 12 to 63 months). Assessment of pain and dysfunction was on a scale of 0 (no pain/dysfunction) to 10 (severe enough to prompt request for amputation and required use of a wheelchair). RESULTS: Pain scores improved from a preoperative average of 8.7 points (range, 6 to 10 points) to a postoperative average of 4.6 points (range, 0 to 10 points); dysfunction improved from a preoperative average of 7.3 points (range, 3 to 10 points) to a postoperative average of 4.4 points (range, 0 to 9 points). Although 17/25 patients were satisfied with the procedure, only 14/25 stated they would undergo the surgery again. All eight patients who exhibited no improvement had preoperative and intraoperative evidence of an idiopathic etiology and/or intraneural damage. Preoperatively, 18/25 patients could not work; postoperatively, that number improved to 8/25. CONCLUSIONS: Vein wrapping of lower extremity peripheral nerves is most effective in relieving symptoms related to adhesive neuralgia and less beneficial in the presence of intraneural damage. Although symptoms are rarely relieved completely, vein wrapping typically results in a substantial improvement in symptoms related to scar entrapment of peripheral nerves.

Radiographic and clinical classification of acquired midtarsus deformities.

To develop a classification of midtarsus deformities, clinical examination and weightbearing radiographs were used to evaluate 131 feet in 109 patients (average age, 59+/-11 years) with those deformities. Patients were classified into four types based on anatomic location of the maximum deformity. Type I (N=43) showed deformity at the metatarsocuneiform joints medially and the fourth and fifth metatarsocuboid joints laterally, with plantarmedial and/or medial prominence. Type II (N= 60) had deformity at the naviculocuneiform joint medially and the fourth and fifth metatarsocuboid joints laterally; plantarlateral prominence was characteristic, although one-third had isolated or additional medial prominences. Type III (N=17) had major deformity in the perinavicular region, with a prominence plantarcentrally or plantarlaterally. Type IV (N=11) had deformity at the transverse tarsal joints with variable prominences. Each type was further subdivided into stages A, B, and C based on the severity of the deformity. In stage B, the midtarsus was coplanar with the metatarsocalcaneal plane. In stage A, the midtarsus was above this plane. In stage C, the midtarsus was below this plane. We concluded that midtarsus deformities can be classified as one of four types and one of three stages. Additional study is warranted to correlate this system with prognosis and treatment for this pathologic process.

Salvage of pseudoarthrosis after tibiotalar arthrodesis.

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.

Histopathologic findings in autogenous saphenous vein graft wrapping for recurrent tarsal tunnel syndrome: a case report.

Autogenous saphenous vein graft wrapping of the tibial nerve has been described as an effective treatment option for failed tarsal tunnel decompression. Various theories have been proposed to explain how this method works, with little histologic evidence to date. A pathologic investigation of a sectioned nerve that had been previously wrapped provides some insight into these proposals.

Biomechanical evaluation of two different screw positions for fusion of the calcaneocuboid joint.

In triple arthrodesis performed for severe deformity and neuroarthropathy in poorly compliant patients with osteoporotic bone, fixation of the arthrodesis is critical. We biomechanically tested an alternative means of stabilization for calcaneocuboid fusions. In seven matched pairs of fresh-frozen cadaver feet, we removed the soft tissue from around the calcaneocuboid joint, except for the capsule, and we did not resect the articular cartilage. One joint of each pair was fixed with an oblique standard screw, and the contralateral joint was stabilized with an axial screw placed perpendicularly to the joint surface. Testing on an MTS Mini Bionix Test Frame (MTS Systems Corp., Eden Prairie, MN) demonstrated that the axial screw provided significantly higher initial stiffness and maximum load to failure. We concluded that an axial screw provided better fixation of the calcaneocuboid joint.

Result of arthrodesis of the hallux metatarsophalangeal joint using bone graft for restoration of length.

We treated 24 patients (18 women, six men; average age, 46.4 years; (range, 28 to 66 years) with fusion of the hallux metatarsophalangeal (MTP) joint using bone graft for the restoration of the length of the first ray. This procedure was performed after bone loss subsequent to previous surgeries for the correction of hallux valgus and hallux rigidus with: silastic arthroplasty (11), bunionectomy and distal metatarsal osteotomy (six), Keller resection arthroplasty (five), and total joint replacement (two). The indication for performing the arthrodesis with bone graft was a short first metatarsal, and associated metatarsalgia of the lesser metatarsals in addition to a painful MTP joint with or without deformity. This bone loss was associated with avascular necrosis of the first metatarsal (nine patients) and with osteomyelitis (seven patients). Of the 24 patients, 14 underwent additional concurrent surgery for correction of hammer toes (10), excision of a Morton's neuroma (two), and lesser metatarsal osteotomy (two). All patients were examined clinically and radiographically at a mean interval of 62.7 months after surgery (range, 26 to 108 months). The patients were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) hallux and MTP 100-point outcome scale. Arthrodesis occurred in 19/24 patients (79.1%) at a mean of 13.3 weeks (range, 11 to 16 weeks), and the first ray was lengthened by a mean of 13 mm (range, 0 to 29 mm). Of the five nonunions, two were asymptomatic, and three were subsequently revised successfully, with arthrodesis occurring at a mean of 10.7 weeks. Complications included one deep infection requiring intravenous antibiotics for treatment of osteomyelitis and two minor superficial wound infections. The mean AOFAS score improved from 39 points (range, 22 to 60 points) to 79 points (range, 64 to 90 points). All patients were satisfied with the final outcome of treatment and stated that they would undergo the surgical procedure again. We concluded that arthrodesis of the hallux MTP joint with bone graft to restore bone loss and length of the first ray may be a worthwhile procedure despite the technical difficulty and the high rate of nonunion.

Midfoot fusion technique for neuroarthropathic feet: biomechanical analysis and rationale.

To test the hypothesis that a plate applied to the plantar (tension) side of the medial midfoot provides stronger fixation than midfoot fusion with screw fixation, we biomechanically compared the two constructs for midfoot fusion. We created a model of midfoot instability in eight matched pairs of cadaver legs by section of joint capsule, ligaments, and tendons about Lisfranc's joints, and then performed a load-to-failure study to compare the fixation provided by a plantarly applied third tubular plate with that by cortical screws. After an initial load deformation curve to 1000 N was obtained, specimens were cyclically loaded at 200 to 750 N for 3000 cycles and then loaded to failure (screw pullout, fracture, or deformation >3 mm). Comparing the plantar plate and midfoot fusion with screw fixation constructs, a plate applied to the plantar (tension) aspect of the medial midfoot provides a stronger, sturdier construct than does midfoot fusion with screw fixation.

Tendon transfer combined with calcaneal osteotomy for treatment of posterior tibial tendon insufficiency: a radiological investigation.

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.