Foot and ankle infections after surgery.

Infection after foot and ankle surgery or trauma can range from the common superficial cellulitis to the less common deep soft tissue or bone infections that can have disastrous consequences. The emergence of antibiotic-resistant organisms has made treatment of infection more difficult, even though promising new antibiotics are being developed. Prevention of infection, through proper patient selection and meticulous surgical technique, is essential to satisfactory outcomes.

Orthotic and prosthetic devices in partial foot amputations.

With advanced surgical techniques and orthotic, as well as prosthetic devices, partial foot amputations have become a viable alternative. Orthotics can help restore stability, maintain support, and protect function of the residual limb. The authors discuss orthotic and prosthetic management of patients who have undergone toe amputations; ray amputations; transmetatarsal, Lisfranc-, or Chopart-level amputations.

An extensometer for global measurement of bone strain suitable for use in vivo in humans.

An axial extensometer able to measure global bone strain magnitudes and rates encountered during physiological activity, and suitable for use in vivo in human subjects, is described. The extensometer uses paired capacitive sensors mounted to intraosseus pins and allows measurement of strain due to bending in the plane of the extensometer as well as uniaxial compression or tension. Data are presented for validation of the device against a surface-mounted strain gage in an acrylic specimen under dynamic four-point bending, with square wave and sinusoidal loading inputs up to 1500 mu epsilon and 20 Hz, representative of physiological strain magnitudes and frequencies. Pearson's correlation coefficient (r) between extensometer and strain gage ranged from 0.960 to 0.999. Mean differences between extensometer and strain gage ranged up to 15.3 mu epsilon. Errors in the extensometer output were directly proportional to the degree of bending that occurs in the specimen, however, these errors were predictable and less than 1 mu epsilon for the loading regime studied. The device is capable of tracking strain rates in excess of 90,000 mu epsilon/s.

Treatment strategies for acute fractures and nonunions of the proximal fifth metatarsal.

There are at least three distinct fracture patterns that occur in the proximal fifth metatarsal: tuberosity avulsion fractures, acute Jones fractures, and diaphyseal stress fractures. Each of these fracture patterns has its own mechanism of injury, location, treatment options, and prognosis regarding delayed union and nonunion. Tuberosity avulsion fractures are the most common in this region of the foot. The majority heal with symptomatic care in a hard-soled shoe. The true Jones fracture is an acute injury involving the fourth-fifth intermetatarsal facet. These injuries are best treated with non-weight-bearing cast immobilization for 6 to 8 weeks. The rate of successful union with this treatment has been reported to be between 72% and 93%. For the high-performance athlete with an acute Jones fracture, early intramedullary-screw fixation is an accepted treatment option. Nonacute diaphyseal stress fractures of the proximal fifth metatarsal and Jones fractures that develop into delayed unions and nonunions can both be managed with operative fixation with either closed axial intramedullary-screw fixation or autogenous corticocancellous grafting. Early results with the use of electrical stimulation are promising; however, prospective studies are needed to better define the role of this modality in managing these injuries.

A site-specific evaluation of mercury toxicity in sediment.

A site-specific evaluation of mercury toxicity was conducted for sediments of the Calcasieu River estuary (Louisiana, USA). Ten-day whole-sediment toxicity tests assessed survival and growth (dry weight) of the amphipods Hyalella azteca and Leptocheirus plumulosus under estuarine conditions (10 ppt salinity). A total of 32 sediment samples were tested for toxicity, including 14 undiluted site sediment samples and 6 sediment dilution series. All sediment samples were analyzed for total mercury and numerous other chemical parameters, including acid volatile sulfide (AVS) and simultaneously extracted metals (SEM). No toxicity attributable to mercury was observed, indicating that a site-specific threshold for total mercury toxicity to amphipods exceeds 4.1 mg/kg dry weight. Site-specific factors that may limit mercury bioavailability and toxicity include relatively high sulfide levels. Additionally, the chemical extractability of mercury in site sediments is low, as indicated by SEM mercury analyses for three sediment samples containing a range of total mercury concentrations.http://link. springer-ny.com/link/service/journals/00244/bibs/37n4p488.++ +html

Checkrein deformity--an unusual complication associated with a closed Salter-Harris Type II ankle fracture: a case report.

This article presents a case of tethering of the flexor hallucis longus (FHL) tendon (checkrein deformity) and rupture of the posterior tibialis tendon after a closed Salter-Harris Type II ankle fracture. Delayed repair was affected by tenolysis of the FHL and flexor digitorum longus tendons and tenodesis of the posterior tibialis to the flexor digitorum longus tendon. This case represents the first such report of concomitant entrapment of the FHL tendon and rupture of the posterior tibialis tendon after a closed ankle fracture.

Diagnosing and treating plantar fasciitis: a conservative approach to plantar heel pain.

Plantar fasciitis is the most common cause of pain at the weight-bearing surface of the heel, and may coexist with other sources of heel pain. This has led to a confusing array of treatment strategies, including surgery. We offer a simple, effective diagnostic and treatment algorithm that emphasizes nonsurgical treatment options for this often frustrating condition.

Posterior tibial tendon insufficiency. Its Diagnosis, Management, and Treatment.

Posterior tibial tendon dysfunction, once thought to be a rare clinical entity, has been observed to be a major cause of acquired flatfoot deformity in adults. Several risk factors have been identified, ranging from inflammatory conditions to obesity. A physical examination using a series of tests, including the single-limb rise, first-metatarsal rise sign, and the "too-many-toes" sign, used in combination with selected radiographic imaging techniques, allows classification of the severity of disease. This staging system then serves as the basis for formulating the treatment options, which include nonoperative as well as operative alternatives. Conservative treatment involves rest, anti-inflammatory medication, orthotic devices, and modifications to shoes. Operative options are numerous and include primary tendon repair, tendon transfer, osteotomies, and arthrodesis.

Diagnosing and treating hallux valgus: a conservative approach for a common problem.

For most patients with hallux valgus, the problem is caused by wearing shoes that are too tight, and conservative measures can help. We review how primary care physicians can evaluate and treat this problem, and when to refer to an orthopaedic surgeon.

Delayed tension pneumothorax complicating central venous catheterization and positive pressure ventilation.

Pneumothorax is the most common complication after central venous catheterization. The diagnosis of pneumothorax may be delayed for hours or days, in some instances because of minimal clinical symptoms or radiographic signs on initial evaluation, or in other instances because of late presentation precipitated by positive pressure ventilation. A case is presented in which a patient developed a tension pneumothorax while under general anesthesia 10 days after central venous line placement. A review of the literature suggests that delayed pneumothorax has an incidence of approximately 0.4% of all central venous access attempts, is much more common after subclavian than internal jugular approaches, especially in difficult or multiple attempts, is asymptomatic in 22%, and results in tension pneumothorax in 22%. End-expiratory upright chest radiographs, the optimal radiographic technique for detection of small pneumothoraces, were obtained in only 19% of reviewed cases. Supine views, the least sensitive radiographic technique, should be carefully reviewed for evidence of basilar hyperlucency, a deep sulcus sign, or a double diaphragm sign. In patients unable to tolerate the upright position, supine views should be supplemented with lateral decubitus, oblique, or cross-table lateral views. Emergency physicians should be aware of the possibility of delayed pneumothorax, as well as optimal radiographic technique for demonstration of small pneumothoraces, and subtle radiographic findings in supine or semirecumbent patients.

Biomechanical analysis of canine bone lengthened by the callotasis method.

The mechanical integrity of tibial bone treated by distraction osteogenesis (callotasis) using an Orthofix external fixator was evaluated in a group of 6 dogs. Diaphyseal corticotomies were performed on Day 0. Distraction was begun on Day 8, at a rate of 0.33 mm every 8 hours. On Day 34, the Orthofix frame was locked. On Day 56, the frames were removed and the dogs were euthanized. Radiographs were taken weekly to assess regenerate bone formation and extent of tibial bone lengthening, which averaged 12 mm (range, 5-20 mm). One dog showed incomplete bony union that was attributed to pin loosening. Torsional testing of lengthened and contralateral control tibiae resulted in spiral diaphyseal fractures. Five of 6 lengthened tibiae bones fractured within the diaphysis, but outside the regenerate area, suggesting that the strength of the lengthened segment exceeded that of the original diaphysis which was exposed to stress shielding by the external fixator. These observations have led to a method to test and evaluate lengthened bone at the time of frame removal and to monitor the effectiveness of this type of technique.

A model for evaluating the strength of bones lengthened by distraction osteogenesis.

In an effort to evaluate the strength of bones lengthened by distraction osteogenesis, a modified Ilizarov-type external fixator was applied to the right tibiae of five adult mongrel dogs. Diaphyseal corticotomies were performed, and distraction (lengthening) was carried out at a rate of approximately 1 mm per day for 20 days. After completion of the lengthening, the animals were killed, the fixators were removed, and the right and left tibiae were harvested and stripped of soft tissue. The ends of all harvested bones were fixated in polymethylmethacrylate to allow testing on a materials testing system (MTS) machine. Testing under torsional loads was performed on the MTS machine (50 degrees maximum angle of rotation at ten seconds) until failure. The right tibiae were lengthened an average of 12 mm (range, 7-15 mm). The slopes of the linear portion of the torque versus rotation curves were determined. A comparison of slopes revealed a mean change in stiffness between test and control bones of 20.32% (range, 0.64%-40.5%). All tibiae exhibiting mature regenerate bone demonstrated stiffness greater than the matched controls (range, 0.64-24.09% stiffer). Four of five dogs had problems with proximal and distal ring impingement. This study presents a reproducible model for evaluating the strength of bones lengthened by distraction osteogenesis. The lengthened bones that exhibited bony or mature regeneration were as strong as the control bones.

Upper GI bleeding in an urban hospital. Etiology, recurrence, and prognosis.

Acute upper gastrointestinal bleeding (UGIB) continues to be a common cause of hospital admission and morbidity and mortality. This study reviews 469 patients admitted to a surgical service of an urban hospital. There were 562 total admissions because 53 patients were readmitted 93 times (recurrence rate, 20%). The most common causes of bleeding, all endoscopically diagnosed, included acute gastric mucosal lesion (AGML) (135 patients, 24%), esophageal varices (EV) (121 patients, 22%), gastric ulcer (108 patients, 19%), duodenal ulcer (78 patients, 14%), Mallory-Weiss tear (61 patients, 11%), and esophagitis (15 patients, 3%). Nonoperative therapy was sufficient in 504 cases (89.5%). Endoscopic treatment was used in 144 cases. Operations were performed in 58 cases (10.5%), including 29% of ulcers. Emergency operations to control hemorrhage were required in only 2.5% of all cases. The rate of major surgical complications was 11% and the mortality rate was 5.2%. There were 58 deaths (12.6%), with 36 deaths directly attributable to UGIB. Factors correlating with death include shock at admission (systolic blood pressure less than 80), transfusion requirement of more than five units, and presence of EV (all p less than 0.001). Most cases of UGIB can be treated without operation, including endoscopic treatment, when diagnostic endoscopy establishes the source. Subsequent operation in selected patients can be done with low morbidity and mortality rates.