Thomas O. Clanton

Prospective Controlled Trial of STAR Total Ankle Replacement versus Ankle Fusion: Initial Results

Background: Mobile-bearing ankle replacements have become popular outside of the United States over the past two decades. The goal of the present study was to perform a prospective evaluation of the safety and efficacy of a mobile-bearing prosthesis to treat end stage ankle arthritis. We report the results of three separate cohorts of patients: a group of Scandanavian Total Ankle Replacement (STAR) patients and a control group of ankle fusion patients (the Pivotal Study Groups) and another group of STAR total ankle patients (Continued Access Group) whose surgery was performed following the completion of enrollment in the Pivotal Study. Materials and Methods: The Pivotal Study design was a non-inferiority study using ankle fusion as the control. A non-randomized multi-centered design with concurrent fusion controls was used. We report the initial perioperative findings up to 24 months following surgery. For an individual patient to be considered an overall success, all of the following criteria needed to be met: a) a 40-point improvement in total Buechel-Pappas ankle score, b) no device failures, revisions, or removals, c) radiographic success, and d) no major complications. In the Pivotal Study (9/00 to 12/01), 158 ankle replacement and 66 arthrodesis procedures were performed; in the Continued Access Study (4/02 to 10/06), 448 ankle replacements were performed, of which 416 were at minimum 24 months post-surgery at time of the database closure. Results: Major complications and need for secondary surgical intervention were more common in the Pivotal Study arthroplasty group than the Pivotal Study ankle fusion group. In the Continued Access Group, secondary procedures performed on these arthroplasty patients decreased by half when compared with the Pivotal Arthroplasty Group. When the Pivotal Groups were compared, treatment efficacy was higher for the ankle replacement group due to improvement in functional scores. Pain relief was equivalent between fusion and replacement patients. The hypothesis of non-inferiority of ankle replacement was met for overall patient success. Conclusion: By 24 months, ankles treated with STAR ankle replacement (in both the Pivotal and Continued Access Groups) had better function and equivalent pain relief as ankles treated with fusion. Level of Evidence: II, Prospective Controlled Comparative Surgical Trial

Hamstring strains in athletes: diagnosis and treatment.

&NA; Hamstring strains are among the most common injuries (and reinjuries) in athletes. Studies combining electromyography with gait analysis have elucidated the timing of activity of the three muscles of the hamstring group; they function during the early‐stance phase for knee support, during the late‐stance phase for propulsion, and during midswing to control the momentum of the leg. Muscle injury, whether partial or complete, occurs at the myotendinous junction, where force is concentrated. The healing response begins with inflammation, associated edema, and localized hemorrhage. After an initial period of reduced tension, the healing muscle regains strength rapidly as long as reinjury does not occur. Although the use of anti‐inflammatory medication is a keystone of treatment, a certain degree of inflammation is necessary for removing necrotic muscle fibers and rescaffolding to allow optimal recovery. The protocol of rest, ice, compression, and elevation is still the preferred first‐aid approach. After a brief period of immobilization (usually less than 1 week for even the most severe strain), mobilization is begun to properly align the regenerating muscle fibers and limit the extent of connective tissue fibrosis. Concurrent pain‐free stretching and strengthening exercises (beginning with isometrics and progressing to isotonics and isokinetics) are essential to regain flexibility and prevent further injury and inflammation. Readiness for return to competition can be assessed by isokinetic testing to confirm that muscle‐strength imbalances have been corrected, the hamstring‐quadriceps ratio is 50% to 60%, and the strength of the injured leg has been restored to within 10% of that of the unaffected leg. The only indication for surgery is a complete rupture at or near the origin from the ischial tuberosity or distally at its insertion (either soft‐tissue avulsion with a large defect or bone avulsion with displacement by 2 cm).

Hallux rigidus: treatment by cheilectomy

Cheilectomy, the excision of an irregular osseous rim that interferes with motion of a joint, was performed on the distal part of the first metatarsal of twenty-five patients who had hallux rigidus. Relief of pain was achieved in all but three patients, whose cases were considered as failures. Joint motion improved by an average of 20 degrees, and it was in an acceptable range in twenty-three patients. There were no complications other than persistence of swelling in six patients. No patient required additional operative intervention during an average follow-up of fifty-six months. We concluded that cheilectomy is a better method of treatment for hallux rigidus than arthrodesis, resection arthroplasty, or arthroplasty with the use of a flexible implant.

Bioabsorbable implants: review of clinical experience in orthopedic surgery.

Bioabsorbable implants are widely used in orthopedic surgery today and the worldwide market is expanding rapidly. Despite the popularity of these implants, reports of complications continue to appear in the literature. Although the complications rarely have an adverse affect on long-term outcomes, the reports are too numerous to be mere isolated incidents related to one specific implant. Complications have been reported with most of the commercially available implant materials with varying incidence rates and severities of reactions to the implants. The purpose of this review is to summarize the adverse events that have been reported in clinical trials of bioabsorbable implants in orthopedic surgery.

Intraspecies and interspecies comparison of the compressive properties of the medial meniscus

Quantification of the compressive material properties of the meniscus is of paramount importance, creating a “gold-standard” reference for future research. The purpose of this study was to determine compressive properties in six animal models (baboon, bovine, canine, human, lapine, and porcine) at six topographical locations. It was hypothesized that topographical variation of the compressive properties would be found in each animal model and that interspecies variations would also be exhibited. To test these hypotheses, creep and recovery indentation experiments were performed on the meniscus using a creep indentation apparatus and analyzed via a finite element optimization method to determine the material properties. Results show significant intraspecies and interspecies variation in the compressive properties among the six topographical locations, with the moduli exhibiting the highest values in the anterior portion. For example, the anterior location of the human meniscus has an aggregate modulus of 160 ± 40 kPa, whereas the central and posterior portions exhibit aggregate moduli of 100 ± 30 kPa. Interspecies comparison of the aggregate moduli identifies the lapine anterior location having the highest value (450 ± 120 kPa) and the human posterior location having the lowest (100 ± 30 kPa). These baseline values of compressive properties will be of help in future meniscal repair efforts.

Thromboembolism after foot and ankle surgery : A multicenter study

Thromboembolic disease presents a potentially fatal complication to patients undergoing orthopaedic surgery. Although the incidence after hip and knee surgery has been studied and documented, its incidence after surgery of the foot and ankle is unknown. For this reason, a prospective multicenter study was undertaken to identify patients with clinically evident thromboembolic disease to evaluate potential risk factors. Two thousand seven hundred thirty-three patients were evaluated for preoperative risk factors and postoperative thromboembolic events. There were six clinically significant thromboembolic events, including four nonfatal pulmonary emboli, after foot and ankle surgery. The incidence of deep vein thrombosis was six of 2733 (0.22%) and that of nonfatal pulmonary emboli was four of 2733 (0.15%). Factors found to correlate with an increased incidence of deep vein thrombosis were nonweightbearing status and immobilization after surgery. On the basis of these results, routine prophylaxis for thromboembolic disease after foot and ankle surgery probably is not warranted.

Injuries to the Metatarsophalangeal Joints in Athletes

Injury to the metatarsophalangeal joints in sports has become an increasing problem with the advent of more flexible shoewear and artificial playing surfaces. These injuries vary from mild sprains to severe tearing of the capsuloligamentous complex including avulsion fractures. This may include a compression fracture of the metatarsal head in the more severe cases. At the extreme, dislocation or fracture-dislocation of the metatarsophalangeal joint occurs. The findings in 62 cases of these injuries in Rice University athletes from 1971 to 1985 are presented. Treatment follows a standard regimen of ice, taping and anti-inflammatory medication with gradual return to sports activity as symptoms allow. Recommendations for preventive therapy include stiffening the forefoot in athletic shoes or the use of an orthotic device. This should reduce the incidence of long-term sequelae.

Reconstruction for Subtalar Instability: A Review:

Instability of the subtalar joint has become a more well-defined clinical entity in recent years. While there have been several articles which have discussed diagnosis of this condition, there has been little written on the surgical treatment. Reconstructive techniques with which we have had experience are presented. Technical aspects of these methods are described in detail.

Continuous Lateral Sciatic Blocks for Acute Postoperative Pain Management after Major Ankle and Foot Surgery

We developed a continuous lateral sciatic nerve infusion technique for postoperative analgesia. Methods: A 10-cm insulated Tuohy needle connected to a nerve stimulator was introduced posteriorly between the biceps femoris and vastus lateralis groove 10 cm cephalad from the tip of the patella. After proper positioning of the insulated needle, a 20-gauge catheter was placed in proximity to the sciatic nerve. Results: Continuous lateral sciatic infusion of 0.2% ropivacaine was associated with a significant reduction of morphine consumption by 29% and 62% during postoperative days one and two, respectively, in patients who underwent open reduction and internal fixation of the ankle. Conclusion: Continuous lateral sciatic infusion of 0.2% ropivacaine represents an alternative for acute postoperative pain control after major ankle and foot surgery.

Evaluation of Compression in Intramedullary Hindfoot Arthrodesis

Compression was evaluated in an intramedullary hindfoot arthrodesis cadaver model using an external fixator and a “second generation” intramedullary compression nail. Four cadaver specimens were used. Four trials were done with each specimen. Trial 1: manual compression with the 1st generation nail. Trial 2: external fixator for compression with the 1st generation nail. Trial 3: external fixator for compression with the 2nd generation nail. Trial 4: nail-mounted compression device with the 2nd generation nail. In Trial 1 it was not possible to obtain or maintain compression. In Trial 2 large values of compression were obtained with the external fixator, however compression was not maintained after the first generation nails were locked and the fixator was removed. In Trial 3 large values of compression were obtained with the external fixator, but minimal compression was maintained after the second-generation nails were locked and the fixator was removed. In Trial 4 large values of compression were obtained with the compression device and greater than 60% of the compression was maintained after the nail was locked and the compression device was released. The study revealed that both the external fixator and the compression device could produce compression. The external fixator is useful as an aid in the O.R. However, in this study significant compression was maintained only with utilization of the compression device.