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BACKGROUND: Triple arthrodesis is used to treat major deformities of the hindfoot and is often performed in young patients. The purpose of this study was to assess the long-term outcomes of triple arthrodesis in young patients. METHODS: Sixty-seven feet of fifty-seven patients were evaluated at an average of twenty-five and forty-four years after triple arthrodesis. The most common indication for the operation was neuromuscular imbalance of the hindfoot, which was secondary to poliomyelitis in thirty-seven feet (55 percent), Charcot-Marie-Tooth disease in six (9 percent), spinal cord abnormalities in four (6 percent), cerebral palsy in three (4 percent), and Guillain-Barré syndrome in one (1 percent). RESULTS: Fifty-two feet (78 percent) had some residual deformity after the arthrodesis. However, these deformities appeared to be nonprogressive between 1973 and 1994. Pseudarthrosis occurred in thirteen feet. Thirty feet or ankles (45 percent) were painful at the first follow-up evaluation, and thirty-seven feet or ankles (55 percent) were painful at the second follow-up evaluation. Of the thirty feet or ankles that were painful at the first follow-up evaluation, twenty-three were painful at the second follow-up evaluation. Of the thirty-seven feet or ankles that were not painful at the first follow-up evaluation, fourteen were painful at the second follow-up evaluation. Eighteen patients (32 percent) needed walking support at the time of the first follow-up, and thirty-nine patients (68 percent) needed it at the time of the second follow-up. Two of the patients who needed support at the first follow-up evaluation did not need it at the second follow-up evaluation. At the first follow-up evaluation, twenty-one ankles (31 percent) had no radiographic evidence of degenerative changes. However, by the second follow-up evaluation, all of the ankles had some degenerative changes. Similar progressive arthritic findings were noted at the naviculocuneiform and tarsometatarsal joints. According to the system of Angus and Cowell, the overall result at the time of the first follow-up was rated as good in fifty feet (75 percent) and as fair in seventeen feet (25 percent). At the time of the second follow-up, nineteen feet (28 percent) were rated as good, forty-six (69 percent) were rated as fair, and two (3 percent) were rated as poor. CONCLUSIONS: Despite progressive symptoms and radiographic degeneration in the joints of the ankle and midfoot, fifty-four patients (95 percent) were satisfied with the result of the operation. The triple arthrodesis was a satisfactory solution for imbalance of the hindfoot in this group of patients.

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Health care reform proposals include many sections related to graduate medical education, number of physicians needed, and specialty distribution of physicians. In our attempts to address these concerns, we must examine the present method of graduate medical education in orthopedics and its subspecialties and understand how a variety of proposals might impact this. We then must try to be innovative in our discipline as these proposals move through government and regulatory channels. All orthopedists should be concerned with and involved in this process.

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Bone is a complex, living, constantly changing tissue. The architecture and composition of cancellous and cortical bone allow the skeleton to perform its essential mechanical functions. The stiffer cortical bone responds more slowly to changes in loads while cancellous bone has a much larger surface area per unit volume and a greater rate of metabolic activity. Periosteum covers the external surface of bone and consists of two layers: an outer fibrous layer and an inner more cellular and vascular layer. The inner osteogenic layer or cambium layer can form new bone while the outer layer forms part of the insertions of tendons, ligaments and muscles. The cortical bone of diaphyses and metaphyses has a dual blood supply that allows loss of one source of circulation without adversely affecting the viability of the tissue. Many epiphyses, even in adults, depend only on a single source of blood supply, the penetrating epiphyseal vessels. For this reason epiphyseal bone may infarct more easily than metaphyseal or diaphyseal bone. The bone matrix has an organic component, primarily type I collagen, which gives it tensile strength and an inorganic component, primarily hydroxyapatite, which gives it stiffness to compression. Specialized populations of bone cells form, maintain and remodel this matrix. We recognize four types of bone cells based on their locations, morphology and functions: osteoprogenitor cells, osteoblasts, osteocytes and osteoclasts. Osteoblasts develop from undifferentiated cells while osteocytes form from osteoblasts. Osteoclasts have a separate stem cell line, blood-borne monocytes. Bone matrix apparently attracts these monocytes and stimulates their differentiation into osteoclasts. The processes of bone modeling and remodeling require osteoclastic resorption of bone matrix and deposition of a new matrix by osteoblasts. Modeling shapes and reshapes bones during growth and stops at skeletal maturity. Physiologic remodeling does not change bone shape and consists of bone resorption followed by bone deposition in approximately the same location. Since it continues throughout life it appears to be important for maintenance of the skeleton, but its exact function remains obscure. Adaptive remodeling is the response of the bone to altered loads and may alter the strength, density and shape of bone. In recent years understanding of the control of bone cell function has increased significantly. The study of electrical effects on bone formation has lead to new treatments of nonunions and delayed unions. Physicians have applied understanding of matrix-induced bone formation to reconstruction of skeletal defects.(ABSTRACT TRUNCATED AT 400 WORDS)

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Of 26 talectomies with an average follow-up period of 20 years, 24 (92%) were judged to have satisfactory results. The average age at surgery was 10.25 years; however, there is no ideal age for performing talectomies. The results seem to be equally good regardless of the preoperative deformity. The procedure did produce stable, painless plantigrade feet. Talectomy has a place in orthopedic surgery today. However, this drastic procedure is indicated only in those feet where the deformity is rigid and severe, where a plantigrade foot is required in patients who are younger than the age usually recommended for triple arthrodesis, and where experience has shown that other, less radical approaches would be unsatisfactory.

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We evaluated the results of fifty-eight fascia lata transfers and anterior hip releases in thirty-three myelodysplastic patients with a minimum follow-up of 10.9 years. The procedure does not appear to achieve hip stability or prevent recurrent flexion deformity. Pelvic obliquity occurs secondary to scoliosis and results in increased instability of the hip on the high side and ischial decubitus ulcers on the low side. The degree of scoliosis and pelvic obliquity is related to the level of neural involvement. Similarly, ambulatory status is dependent on neural function and is not affected by instability of the hip.

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Complex cognitive processes, such as interpretation of information and problem-solving, form a critical part of medical practice; therefore, the aims of many educational programs include teaching these processes. However, systematic evaluation of students' interpretation of information or problem-solving may be difficult. To determine whether objective test items could measure cognitive processes more complex than recall of isolated facts, the committee of the American Academy of Orthopaedic Surgeons preparing the Orthopaedic In-Training Examination classified test items into three taxonomic levels according to the cognitive process required to answer the item: recall or recognition, interpretation, and problem-solving. Orthopedic residents from 20 universities took the examination and classified items according to the cognitive process they believed they used to answer the questions. Two methods of analysis showed that residents agreed closely with the taxonomic levels assigned by the committee, suggesting that items did test the cognitive process they were designed to measure and that objective assessment of complex cognitive processes is practical and potentially very useful in medical education.

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The foot's response to load during weightbearing is investigated using finite element stress analysis of a two-dimensional model. The analysis predicts the stress states within the plantar aspect tissue during a variety of shoe conditions. Shoe soles with a range of elastic properties are modeled in an attempt to find a shoe sole that minimizes peak stresses within the foot's soft tissue. This presently simplified and idealized model of the foot and shoe during mid-stance demonstrates significant dependency of stress development within the tissue on shoe elastic properties. These results would seem to justify further more detailed and realistic modeling of shoeing mechanics, and systematic efforts to correlate physical measurements and clinical experience with the trends indicated by finite element analyses.

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Seven cases of synovial sarcoma were studied by electron microscopy. The 4 cases of the monophasic spindle type contained elongated cells arranged in sheets and cords; ultrastructurally the cells contained many cytoplasmic processes and were scattered in an amorphous matrix. The monophasic spindle type demonstrates ultrastructural characteristics that are unique and serve to differentiate it from the biphasic pattern and from fibrosarcoma. Three cases of the biphasic variety demonstrated cytologic characteristics of a true glandular epithelium and a malignant spindle cell stroma. The epithelial nature of the biphasic variety is a feature that raises doubt whether synovium is the stem cell.

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We reviewed forty-five patients with congenital constriction bands with an average follow-up of 15.8 years. The family history and associated anomalies were recorded and particular attention was paid to temperature gradients and neurocirculatory deficits with respect to band location. No family history of band constrictions was elicited. Most of our patients were products of first pregnancies and of young mothers. Deformity of the nails was a constant finding in patients with distally located bands. All patients demonstrated at least one other anomaly, most commonly a malformation of the hand. Neural deficits were noted in 23 per cent of the patients, while circulatory findings appeared in 16 per cent. A significant temperature gradient averaging 2.38 degrees Celsius was noted in twenty patients in whom the bands were located proximally. All patients with neural deficits demonstrated a significant temperature gradient. Staged z-plasty was the procedure of choice in surgical release of constriction bands.

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We studied 20 intervertebral disks from cervical, thoracic, and lumbar levels from patients 12 hours to 55-years-old by electronmicroscopy. Tissue was obtained at operation from 10 patients with scoliosis and 6 with herniation of the intervertebral disk. Four intervertebral disks were removed at autopsies performed within 4 hours of death. Banded structures distinct from native collagen were present in the nuclei pulposi of all intervertebral disks but not in the annuli fibrosi. These structures may be an unusual form of collagen, however they closely resemble extracellular banded structures found in frog muscle spindle that may form from find filaments when the muscle spindle increases in length.

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In 25 human intervertebral discs studied by electron microscopy, sheathing collagen-like fibrils by electron-dense cylinders was observed. The sheaths consisted of layers of dense granules 3 to 12 times the diameter of the enclosed collagen-like fibrils, and they appeared to be more frequent in older discs.

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Core biopsy specimens of the proximal femoral growth plate from three patients with slipped capital femoral epiphysis were studied by light and electron microscopy. In the resting zone, the cartilage matrix was composed of large, densely packed collagen fibrils. The cartilage matrix in the zones of chondrocyte hypertrophy where the slippage occurred contained only scattered fine collagen fibrils in a homogeneous ground substance. The change in composition of cartilage matrix in the distal region of the epiphyseal plate may predispose that region to slippage.

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Ultrastructure features of muscle spindles from two patients with myotonic dystrophy are described. Intrafusal muscle fibers exhibit extensive splitting with nuclear bag fibers affected more so than nuclear chain fibers. No sensory endings are present on nuclear chain fibers nor on one nuclear bag fiber throughout the equatorial and myotube regions. Small motor end plates are evident on various segments of split intrafusal fibers in the polar region and some of these extend into the myotube region. Satellite cells are numerous on both nuclear bag and nuclear chain fibers. These frequently occupy the cleft space between segments of split intrafusal fibers. The myotonic dystrophy muscle spindle ultrastructure features seem to closely resemble the appearance of developing mammalian muscle spindles as illustrated with opossum fetal tissue.

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Although previous studies failed to demonstrate elastic fibers in intervertebral discs, electron microscopy of twenty human intervertebral discs obtained at autopsy and operation revealed characteristic elastic fibers in both the annulus fibrosus and the nucleus pulposus. Their contribution to the mechanical properties of the intervertebral disc remains to be determined.

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