Bone density in women: college athletes and older athletic women.

Bone density was studied in intercollegiate athletes and older athletic women. Single-photon densitometry was used to assess bone density parameters at a new distal radial site, the midradius, and the first metatarsus. Dual-photon densitometry assessed bone density of the lumbar spine. Eleven intercollegiate tennis players, 23 swimmers, and 86 older "athletic" women from 23 to 75 years of age were compared with age-matched nonathletic controls. "Athletic" describes adult women who exercised at least three times per week, 8 or more months of the year, for a minimum of 3 years. The radius and metatarsus bone content of intercollegiate athletes was significantly above control values. Lumbar spine density was significantly higher only in tennis players. Mean bone density values for adult "athletic" women were also significantly greater than in age-matched controls. In the oldest athletic group (55-75 years of age) bone measurement values in radius and lumbar spine were in the same range as for younger "athletic" women. In contrast, after 50 years of age, these values in the control population decreased by 0.7%/year. Therefore the largest variance (increase) from age-matched controls occurred in the oldest "athletic" group. Also, we have established a distal radial density value (using our modified site) below which we consider women "at risk" and recommend further bone health evaluation. Only two adult athletic women greater than 55 years of age fell into this category. It is concluded from this cross-sectional study that a regularly maintained athletic program for adult women may reduce the rate of "normal" bone mass loss accompanying age, particularly postmenopausally.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone density in women: a modified procedure for measurement of distal radial density.

This is a cross-sectional study of bone densitometry in greater than 700 normal healthy white women ranging in age from 18 to 98 years. A modified procedure for single-photon bone density analysis of the distal radius is described and compared with dual-photon densitometric measurements of the second through fourth lumbar vertebrae. The distal radial site measured was separated from the ulna by 5 mm. This "5 mm" site was characterized according to trabecular and cortical bone content, measurement reproducibility, positioning precision, and the effects of wrist pronation or supination. The radial site demonstrated a bone density loss of less than 0.1%/year for normal women 25-50 years of age, increasing to 0.7%/year after 50 years of age. In contrast to the variability and inconsistency obtained by us and others utilizing the standard "9/10" site, bone loss with age at the new "5 mm" site correlated closely with generalized bone mineral loss of the axial skeleton. We suggest that there is a unique role for single-beam densitometric measurements of the radius, permitting the rapid and relatively inexpensive evaluation of large populations of women without requiring a visit to a medical center. Such a process can select those requiring further evaluation or medical attention.

Bone density in osteopenic women: a modified distal radius density measurement procedure to develop an "at risk" value for use in screening women.

This study measured radial and lumbar spine bone density in postmenopausal white female patients with nontraumatic fractures and their age-matched controls. Bone density measurements were made with a single-beam densitometer. Distal radial bone density measurements were made at the site at which the radius and ulna are separated by 5 mm, which is approximately 5 mm from the distal radioulnar joint. Lumbar spine density was obtained using a dual-beam densitometer. Density at the commonly used "2/3" site near the midradius was also measured. Forty-six crush fracture osteoporotic patients, 35 hip fracture patients, and 20 osteopenic patients referred to the clinic for back pain or excessive bone loss but with no history of nontraumatic fracture were studied. Bone density values at all sites in the patient populations were statistically reduced from control values (p less than 0.01). At a mean age of 62 years, density of the midradius was 12% below the control value. However, both vertebral and distal radial densities ("5 mm" site) were 25% below control values. The spine/distal radius ratio remained constant. It was demonstrated that bone density at the modified distal radial site could be used to predict vertebral density in osteopenic patients. An "at risk" value useful in screening procedures was determined as that distal radius density value greater than or equal to 95% of all values from fracture patients--325 mg/cm2. It is concluded that distal radial density at the new "5 mm" site can be used in conjunction with midradius density as a preliminary test for both generalized and trabecular bone mass loss in women.

Monocytic origin of fibroblasts: spontaneous transformation of blood monocytes into neo-fibroblastic structures in osteomyelosclerosis and Engelmann's disease.

We describe here two pathological situations, osteomyelosclerosis and Engelmann's disease, in which HLA-DR blood monocytes modulate to the fibroblastic class, in long-term culture. Monocytes/macrophages were identified by immunofluorescence, using monoclonal antibodies against surface markers (Leu M3, CD 68, and HLA-DR) and the neo-fibroblasts by electron microscopy and immunofluorescence using monoclonal antibodies against a cytoplasmic enzyme specifically involved in the synthesis of collagen (5B5). Macrophages makers were found on the neo-fibroblasts, whereas HLA-DR macrophages expressed the cytoplasmic marker 5B5. Since osteoblasts are classically derived from fibroblasts, the significance of the in vitro differentiation of monocytes/macrophages into fibroblasts to the in vivo mechanism leading to excessive osteoblastic proliferation in both osteomyelosclerosis and Engelmann's disease, is discussed. The possible involvement of this pathway leading from monocytes to fibroblasts and osteoblasts in the normal process of bone modeling and remodeling in questioned.

Results of lumbosacral fusion for degenerative disc disease with and without instrumentation. Two- to five-year follow-up.

Functional and surgical outcomes are reported in two consecutive groups of patients who underwent one- and two-level lumbosacral fusion. The first group underwent standard posterolateral lumbosacral fusion, and the second group underwent lumbosacral fusion with compression U-rod instrumentation. Fusions were carried out over all painful, abnormal levels documented by discography. the pseudarthrosis rate without instrumentation was 35%, in contrast to 6% with instrumentation. In both groups of patients with chronic low-back pain secondary to degenerative disc disease, solid lumbosacral fusion was associated with decreased pain and higher return to work rates. Poorest results were associated with prolonged periods of preoperative disability and long-term disability claims.

Diagnostic findings in painful adult scoliosis.

The purpose of this study was to document the diagnostic findings in a group of adult patients presenting with both scoliosis and pain. Fifty-five adults were evaluated by medical history, physical examination, radiography, myelography followed by computed tomography, discography followed by computed tomography, and single- and dual-photon densitometry. Curves were 49% adult degenerative onset, 44% idiopathic. The older degenerative patients had myelographic defects most commonly within the primary curve and multiple abnormal, not necessarily painful, discs throughout the lumbar spine on discography. The idiopathic group had myelographic defects most commonly in a compensatory lumbar or lumbosacral curve. On discography, all idiopathic patients had at least one abnormal, painful disc, and 88% had their pain reproduced. Pain-producing pathology was frequently identified in areas that would not have been included in the fusion area according to accepted rules for treatment of idiopathic scoliosis.

Cervical discography: clinical implications from 12 years of experience.

STUDY DESIGN: Positive pain responses provoked in an inclusive series of cervical discograms performed over a 12-year period were categorized by level and reviewed. OBJECTIVES: To report the prevalence of cervical pathology over an entire series of patients, to determine whether a reproducible pattern of concordant pain could be associated with each symptomatic level identified, and to calculate the rate of complications. SUMMARY OF BACKGROUND DATA: Cloward wrote the first articles explaining the technique of cervical discography and reported on the pain responses induced. Currently, the technique is viewed as an invaluable diagnostic tool, but it also is criticized for failing to contribute unique information beyond that available from imaging studies despite the inherent risks. METHODS: A series of 173 cervical discograms performed over 12 years was examined. Pain responses provoked and recorded during discography were grouped by disc level and examined for recurring patterns. The prevalence of disc pathology was calculated. RESULTS: In all, 807 discs were injected, and 404 concordant pain responses (50%) were elicited. Three or more abnormal disc levels were identified in more than half of the patients. Complications developed in four patients (2.3%). No further complications were reported. Surgical treatment was indicated as viable in only 35 studies. CONCLUSIONS: Discography is a safe and valuable diagnostic procedure showing characteristic pain patterns that may have clinical significance. In more than half of the studies, three or more levels were identified as pain generators, suggesting that treatment decisions based on information from fewer discs injected during discography may be tenuous.

Degenerative adult onset scoliosis.

There are people who have no history of scoliosis who develop spinal deformity of a progressive nature as adults, associated with severe degenerative disc disease. The clinical syndrome associated with this deformity is not well documented. In an attempt to describe this clinical syndrome more precisely, 21 patients with the diagnosis of degenerative scoliosis were identified and reviewed. Review included history with pain drawings when available, physical examination, bone densities, and standing spinal roentgenograms. Patients with spinal compression fractures, spondylolyses, prior history of scoliosis or radiographic findings consistent with an idiopathic scoliosis were excluded. Our review shows that these patients can develop, along with progressive scoliosis, loss of lumbar lordosis with a resulting flat back deformity. These patients commonly present in the sixth decade with a predominantly stenotic symptom complex, but often lack the classic feature of relief in a sitting posture. The number of male and female patients was approximately equal. Roentgenogram findings show a high angle deformity over a short number of spinal segments and an absence of bony features associated with idiopathic scoliosis such as lateral vertebral wedging and alterations of the lamina. The incidence of this condition remains to be established.

The relative value of lumbar roentgenograms, metrizamide myelography, and discography in the assessment of patients with chronic low-back syndrome.

This prospective study evaluated the relative value of lumbar roentgenograms, metrizamide myelography, and discography in identifying structural sources for chronic low-back syndrome. One hundred and eight patients with chronic low-back syndrome were evaluated. Patients had not previously had pathology identified which could explain their pain. On discography, 83 patients (78%) had their pain reproduced at least one abnormal level, identifying a structural component to their pain. Only 22 patients (21%) had all levels of pathology identified by roentgenograms and an additional 17 (16%) had pathology appropriately identified by a combination of myelograms and roentgenograms. Using roentgenograms, myelography, and discography, organic pathology was identified which could explain the patient's symptoms in 100 of 108 patients (93%). Based on this study, we think discography is an important diagnostic tool for use in evaluating patients with chronic low-back syndrome. Discography is essential to adequately identify abnormal levels in patients being considered for fusions. Roentgenograms and myelograms are inadequate evaluation in this chronic pain group in that lack of organic pathology cannot be assumed in the presence of normal roentgenograms and myelograms.

Results of surgical treatment of painful adult scoliosis.

STUDY DESIGN: In a consecutive clinical series, using before and after treatment measures, outcome was evaluated in adults with pain and scoliosis who underwent spinal fusion. OBJECTIVE: This outcome study tested the hypothesis that adult scoliosis patients with chief complaints of pain can have good results, reflected in decreased pain and increased activity postoperatively, when surgical intervention is based not only on analysis of structural deformity, but also on comprehensive evaluation of pain-producing pathology. METHODS: Twenty-eight adults with idiopathic scoliosis and 25 adults with degenerative scoliosis treated with spinal fusion were followed prospectively for 2 to 7 years. All patients had chief complaints of pain and underwent comprehensive evaluations of pain-producing pathology, as well as evaluations of structural deformity. Before initial evaluations, patients completed questionnaires including pain rating, activity level specifically related to standing, sitting, and walking tolerances, ability to work, and period of disability. At a minimum of 24 months postop, patients completed confidential questionnaires seeking report of pain, activity, and work status. These data were compared to responses obtained before surgery. Pseudoarthroses were assessed by superimposed flexion/extension films. RESULTS: The pseudoarthrosis rate was 17.5%, all occurring in patients fused to the sacrum in single posterior procedures. Pain relief was associated with solid fusion (P = .02). Reported pain reduction was 80% among patients with idiopathic scoliosis and 70% among patients with degenerative scoliosis. Improved sitting and walking tolerances were seen in patients with idiopathic scoliosis, and improved standing and walking were seen in patients with degenerative scoliosis.

Spinal bone density following spinal fusion.

Spinal bone densities were assessed in 25 patients following lumbar fusion and bracing, in an attempt to study bone remodeling by noninvasive methods. Dual-photon densitometry was used to study specific areas of autologous bone grafts and adjacent vertebrae above the fusion mass. Measurements were made preoperatively and at 6-week intervals postoperatively. The data for the first 12 months postoperatively are reported here. In all patients there was at first a consistent loss in density in the vertebrae above the fusion mass, averaging 15.7%. This was followed by a gradual density increase such that by 1 year postoperatively, in 60% of the subjects, the density of these vertebrae was higher than the preoperative level. In the grafted areas, bone changes were cyclical, demonstrating a remodeling pattern consistent with that described in animal literature for graft healing and also consistent with modern bone remodeling theory. There was a general tendency toward a gradual increase in the density of the fusion mass.

Humeral shaft fractures in adults.

After evaluating the results of treatment of 100 humeral shaft fractures in adults, we found the simplest, most comfortable, and most satisfactory treatment to be that of a sling and coaptive splinting. In all of the 15 patients who had radial nerve injury, the fracture occurred in the distal half of the humerus. Every patient recovered full radial nerve function. At follow-up, almost all patients who were treated nonoperatively were found to have between 3 degrees and 12 degrees of increased internal rotation of the arm, with a corresponding decrease in external rotation. None of the patients had recognized this change before being informed of it. Less than 25 degrees of angulation caused no functional impairment. The fractures were usually clinically united before eight weeks. All of the seven fractures that took longer than six months to heal occurred in the proximal half of the humerus. Three patients accepted nonunion rather than have surgical treatment. All three had oblique fractures in the proximal third of the humerus; two were helped by a brace. The preferred surgical treatment of delayed union or nonunion is secure internal fixation supplemented with autogenous bone grafting.

A laboratory model demonstrating osteocyte-osteoblast control of plasma calcium concentrations. Table model for plasma calcium control.

This report describes a laboratory model designed to illustrate a newer concept for the control of plasma calcium concentrations. This postulate suggests that plasma calcium levels are the result of a balance or imbalance in opposing calcium ion fluxes between plasma and bone fluid compartments existing around osteocyte-lining cells (osteoblasts) units in bone. The metabolic control of these fluxes is postulated to reside within the lining cells on the surface of bone. These cells serve as a cellular interface between the two fluid compartments. The model described in this report illustrates these principles by using the height of columns of water in cylinders to represent calcium ion concentrations. A water pump, representing the calcium transcellular transport system in the lining cells, maintains a higher level of water in the cylinder representing plasma than in that representing bone fluid. This is accomplished by continuous pumping of water from the bone fluid cylinder to the plasma cylinder. Water is returned to the bone fluid cylinder as long as a differential in the height of water in the two cylinders exists. A constant height of water in the plasma cylinder is maintained when the two fluxes are in equilibrium. A constant height of water in the cylinder representing bone fluid is maintained by the level of water in a much larger cylinder representing calcium equilibrium between the solid and liquid phases of bone. The primary hormone controlling the rate of calcium transfer from bone fluid to blood, or in the model regulating the speed of water pump, is parathyroid hormone.

The presence of lining cells on surfaces of human trabecular bone.

Sixteen human trabecular bone biopsies were obtained from sites located in the ilium and in the area of the greater trochanter of the femur. Patients ranged from 19 to 85 years old and included men and women. All bone surfaces observed contained osteoid. Flat, branched fibroblastic-like cells were observed lining bone surfaces in all biopsy specimens. The presence of these cells was not dependent on age, sex, race, or disease state of the patient. Based on this study, we believe that the majority of human trabecular bone surfaces are covered with these thin lining cells.

Evidence for an important physiological role for calcitonin.

We propose that calcitonin, secreted in response to the intake of food, aids in routing calcium, obtained by intestinal absorption, into bone fluid. Here calcium is temporarily stored in combination with phosphate for return to the extracellular fluid (blood) during intervals between oral intakes of calcium. The net result is a conservation of calcium postprandially and a decrease in parathyroid hormone-induced bone destruction during subsequent fasting periods. Evidence for this postulate is provided in the following six sequential steps from the time a calcium-containing meal is consumed until that portion of calcium stored in bone fluid is utilized during fasting periods to aid in plasma calcium maintenance. (i) Calcitonin secretion is stimulated by feeding and subsequent digestive processes. (ii) Postprandial secretion of calcitonin restricts the efflux of calcium from bone fluid to blood, thereby maintaining parathyroid hormone (PTH) secretion. (iii) In thyroid-intact individuals, both PTH and calcitonin are secreted postprandially and act in concert on calcium homeostasis. (iv) Calcitonin actively moves phosphate into bone and prevents its loss from bone fluid to blood. (v) Postprandial storage of calcium with phosphate occurs in bone fluid of thyroid-intact individuals. (vi) This labile storage form of calcium is the first to be utilized during fasting periods. In the absence of partial disruption of this storage mechanism, rapid development of pathological bone conditions would not be expected because PTH action permits the extended utilization of bone calcium for plasma calcium control. However, augmentation of osteopenic conditions could be expected if long-term low calcium intake were accompanied by a malfunction of this calcitonin-induced system for calcium storage.