Magnetic resonance imaging of shoulder arthropathies.

The role of magnetic resonance imaging in evaluating shoulder arthropathies is evolving. This article reviews 4 of the major arthropathies: septic arthritis, rheumatoid arthritis, calcium pyrophosphate dihydrate (CPPD) deposition disease, and hydroxyapatite disease (HAD), with special attention to their magnetic resonance imaging features. Comfort with identifying these entities allows appropriate and prompt treatment, which is critical for joint preservation in the case of infection, for maximal therapeutic efficacy of disease-modifying drugs in the case of rheumatoid arthritis, and for expediting symptomatic relief in the cases of CPPD deposition disease and HAD.

Rehabilitation after intramedullary skeletal kinetic distractor implantation: a report of two cases and a suggested therapy program.

Adult limb lengthening occurs via distraction osteogenesis and traditionally involves use of an external fixator. Complications after placement of hardware often disrupt rehabilitative efforts and hinder patients' progress. A completely internal limb-lengthening device has been developed and increasingly used, and it may more commonly be seen by a physiatrist in consultation for postoperative rehabilitation.

Mycobacterium tuberculosis infection of the wrist.

Reports of tuberculous infections of the wrist have been scarce, especially during the past 30 years. The diagnosis of tuberculosis may be difficult and requires a high index of suspicion, especially in patients with significant risk factors. Prompt diagnosis and treatment are crucial, as untreated wrist infections can have disastrous outcomes.

Importance of correlating static and dynamic imaging studies in diagnosing degenerative lumbar spondylolisthesis.

Degenerative spondylolisthesis in the lumbar spine is due to long-standing segmental instability. A standing plain radiograph is commonly the only imaging study needed to establish the diagnosis. Translatory motion in spondylolisthesis is traditionally assessed with lateral flexion and extension radiographs.

Optimal selection and preparation of fresh frozen corticocancellous allografts for cervical interbody spinal fusion.

Study Design: Iliac crest corticocancellous allografts for anterior interbody fusion were harvested from six cadavers. The grafts were cut sequentially from left and right crests and randomly assigned to tricortical or bicortical preparations. Their compression strengths then were determined and compared by matched pair analysis.

Optimal selection and preparation of fresh frozen corticocancellous allografts for anterior interbody lumbar spinal fusion.

To determine the effect of graft preparation on graft strength, corticocancellous grafts suitable for anterior interbody fusion were obtained from six cadavers using five different donor bone sites with different graft sectioning orientations and locations. Graft compression strength was determined in simulated physiological loading. The distal tibia and femoral head lumbar interbody grafts are significantly stronger than grafts prepared from other corticocancellous donor sites.

Bioresorbable fracture fixation in orthopedics: a comprehensive review. Part II. Clinical studies.

Bioresorbable materials overcome two major disadvantages of the metal alloys most commonly used in fracture-fixation devices: their extreme stiffness, which causes stress shielding of the underlying bone, and the necessity, in a significant number of cases, of removing metallic implants after fracture healing is complete. The orthopedic surgeon now has the use of polylactic acid, polyglycolic acid, and polydioxanone implants for the fixation of small cancellous bone fractures. The currently available bioresorbable materials lack strength and stiffness and are associated with inflammatory reactions and osteolysis in a significant number of cases.

Bioresorbable fracture fixation in orthopedics: a comprehensive review. Part I. Basic science and preclinical studies.

Metal alloys are currently the most popular materials for manufacture of fracture-fixation devices. Two major disadvantages of these materials are their extreme stiffness, which causes stress shielding of the underlying bone, and the necessity, in a significant number of cases, of removing metallic implants after fracture healing is complete. These shortcomings of metal alloys have led to the study of bioresorbable materials for use in fracture fixation.

Low end interactive image-directed neurosurgery. Update on rudimentary augmented reality used in epilepsy surgery.

Our experience with a very low end interactive image-directed (IIDS) neurosurgical system is presented. The system was developed by the author and consists of a personal desktop computer and a magnetic field digitizer. This low cost solution was pursued as an alternative to available commercial devices which were expensive and not readily modifiable for novel ideas and new applications targeted for Epilepsy surgery.

Boutonniere deformity.

The boutonniere (French for button hole) deformity is a result of an injury to the finger extensor mechanism that causes a characteristic flexion attitude of the proximal interphalangeal joint and distal interphalangeal joint hyperextension. This article reviews the pertinent anatomy, the mechanisms of injury, the diagnosis, and a systematic approach to the prevention and treatment of the boutonniere deformity.

Minor knee trauma as a possible cause of asymmetrical proximal tibial physis closure. A case report.

An unusual case is presented in which minor soft tissue injury may have caused premature asymmetrical closure of the proximal tibial physis resulting in a 30 degrees genu recurvatum that necessitated corrective osteotomy. Awareness of the possibility of a hidden physeal injury in the presence of soft tissue injury and a normal radiograph may lead to its early recognition and treatment.

Tarsal navicular position after complete soft-tissue clubfoot release.

The navicular position was evaluated (according to Simons' criteria) on anteroposterior and lateral roentgenograms of 45 clubfeet that were treated with complete soft-tissue release without internal fixation. The evaluation was performed an average of 28 months after surgery. Position of the navicular correlates well with the functional rating score system.

Biomechanical determination of the optimal number of fixation screws for the sliding hip screw plate.

Laboratory measurement of the tensile forces on the plate fixation screws of the sliding hip nail demonstrated that most of the force is borne by the proximal three screws in an intertrochanteric fracture model. Testing of an intact femur, which simulate a healed femur, demonstrated a proximal shift of the screw forces. Four screws appear adequate for fixation if screw torque is controlled.

Revision surgery in clubfeet.

The reoperated clubfeet of 29 children aged one to 12 years were reviewed. The surgical procedure most often used in revision surgery was recomplete soft-tissue release alone or combined with plantar release, calcaneocuboid fusion, and capsulotomies of the navicular-first cuneiform-first metatarsal joint. In 27 of 29 feet, acceptable results were achieved.

The Ilizarov apparatus for treatment of melorheostosis. Case report and review of the literature.

Traditional conservative and surgical methods of treatment of melorheostosis, such as manipulations, plaster casts, soft-tissue releases, capsulotomies, and osteotomies cause a high recurrence rate. In a 12-year-old girl, flexion contracture of a knee with limb inequality caused by melorheostosis was corrected successfully with the Ilizarov distraction apparatus.

Treatment of complex limb deformities in children with the Ilizarov technique.

Twenty-nine children underwent 36 Ilizarov procedures for a variety of limb deformities. We present the results in 11 patients, six with leg length discrepancies and five with achondroplasia, who underwent lengthening procedures using the Ilizarov method. Lengthening was accomplished in 15 of the 16 procedures (93%).

Closed treatment of canine nonunions by controlled compression and distraction using an Ilizarov fixator: a preliminary study.

The Ilizarov fixator was used for closed treatment of canine nonunions by controlled compression and distraction. The fibrous matrix and cartilage formed within the nonunion site transformed to osteoid and bone with increased vascularity. Healing was demonstrated by substantial bone bridging the nonunion at 6 weeks.

MR imaging of the ankle: normal variants.

Thirty asymptomatic ankles were studied with high-resolution surface coil magnetic resonance (MR) imaging to identify normal structures. Several normal variants were demonstrated, including (a) Cortical irregularity of the posterior tibiotalar joint (should not be mistaken for osteonecrosis) in 27 of 30 cases; (b) normal posterior talofibular ligament with irregular and frayed superior edge simulating a tear in 13 of 30 cases; (c) normal navicular insertion of the posterior tibial tendon with heterogeneous signal intensity in 14 of 30 cases; (d) deltoid ligament inhomogeneity in seven of ten cases; and (e) fluid in the shared peroneal tendons sheath (may be confused with a longitudinal tendon tear) in three of 30 cases. Ankle imaging with the use of MR is still a relatively new procedure.

Rupture of posterior tibial tendon: CT and MR imaging with surgical correlation.

Computed tomography (CT) and magnetic resonance (MR) imaging were performed in 32 cases of clinically suspected chronic tears of the posterior tibial tendon. Surgery was performed in 22 patients (69%). Each case was classified radiographically and surgically as normal or a type 1, type 2, or type 3 rupture.

Malignant round cell tumor of bone with neural differentiation (neuroectodermal tumor).

A malignant round cell tumor primary in bone is reported in a young girl, showing histologically rosette formation and pseudoalveolar spaces. Vimentin, NSE, and S-100 were positive. Electron microscopy demonstrated abundant glycogen and neural features such as cell processes, microtubules, and occasional dense-core granules.