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Pachydermodactyly (PDD) is a rare form of digital fibromatosis characterized by painless soft tissue swelling, primarily about the proximal interphalangeal joints. The skin at the metacarpophalangeal joints, the palm, and the dorsum of the hand may also be involved. Because swelling can occur over the proximal interphalangeal and metacarpophalangeal joints, PDD may be confused with juvenile inflammatory arthropathy and may even occur concurrently. We present the clinical and histopathologic findings of a case of PDD characterized by bilateral proximal phalangeal involvement of the index through little fingers.

Background The bicipital tunnel is the extra-articular, fibro-osseous structure that encloses the long head of the biceps tendon. Methods Twelve cadaveric shoulder specimens underwent in situ casting of the bicipital tunnel with methyl methacrylate cement to demonstrate structural competence (n = 6) and en bloc harvest with gross and histologic evaluation (n = 6). The percentage of empty tunnel was calculated histologically by subtracting the proportion of cross-sectional area of the long head of the biceps tendon from that of the bicipital tunnel for each zone. Results Cement casting demonstrated that the bicipital tunnel was a closed space. Zone 1 extended from the articular margin to the distal margin of the subscapularis tendon. Zone 2 extended from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major tendon. Zone 3 was the subpectoral region. Zones 1 and 2 were both enclosed by a dense connective tissue sheath and demonstrated the presence of synovium. Zone 3 had significantly greater percentage of empty tunnel than zones 1 and 2 did ( P Conclusion The bicipital tunnel is a closed space with 3 distinct zones. Zones 1 and 2 have similar features, including the presence of synovium, but differ from zone 3. A significant bottleneck occurs between zone 2 and zone 3, most likely at the proximal margin of the pectoralis major tendon. The bicipital tunnel is a closed space where space-occupying lesions may produce a bicipital tunnel syndrome. Careful consideration should be given to surgical techniques that decompress both zones 1 and 2 of the bicipital tunnel.

Foreign body synovitis with extensive granulomatous giant cell reaction to refractile polyethelene debris is a complication of subtalar arthroereisis not previously reported. We present two cases whereby STA-peg implants were used to treat bilateral painful flexible flatfoot deformities in children. Two boys, presented at 7 and 10 years of age, 2 years after STA-peg procedures and tendo-Achilles lengthening for painful flatfeet. They each had minimal subtalar motion and pain at the sinus tarsi. Radiographs demonstrated surgical defects in the calcaneus with surrounding high signal on the magnetic resonance imaging (MRI) in the subchondral bone of the calcaneus and talus. Both patients failed conservative management and had their implants removed with good relief of their pain. Histology was submitted at the time of implant removal. We present the radiographic and pathologic findings seen in these two patients with failed subtalar arthroereisis due to extensive implant reaction. The pathologic process seen in these patients is a previously unreported complication of this procedure. We do not recommend arthroereisis in the treatment of painful flexible flatfoot in children.

To our knowledge, mycotic infection of the subacromial bursa has not been reported in the literature. We present the case of a patient with the classic symptoms of impingement syndrome who was found to have a Candida infection of the subacromial bursa. The patient was successfully treated with subacromial decompression and acromioplasty to relieve the impingement as well as with empirical antibiotic treatment for the infection. Our patient was informed that data concerning the case would be submitted for publication. A sixty-five-year-old, right-hand-dominant man was first seen because of progressively increasing pain of more than four months' duration in the right shoulder. He had pain at night, especially when sleeping on the affected side. The patient also reported that the pain limited the range of motion, which restricted his overhead function as well as his ability to reach behind his back. He was barely able to tuck in the back of his shirt, and he had weakness of the affected arm. The patient stated that he had injured the right shoulder while lifting something at work ten months prior to being seen by a physician and that the symptoms had become progressively worse. The patient had been seen by another orthopaedist and was treated unsuccessfully with subacromial injections three times over the course of two months. The subacromial injection consisted of 40 mg of Depo-Medrol (methylprednisolone acetate), 4 mL of lidocaine, and 4 mL of 0.25% Marcaine (bupivacaine). All injection medication was withdrawn from single-use vials. The patient's response to each injection was minimal, with some pain relief with motion initially but with a rapid return to the preinjection state of discomfort. We first saw the patient two months after the onset of symptoms. The medical history was important only for a myocardial infarction sixteen years previously. He reported no …

Purpose To determine whether the amount of polyethylene debris in the interphase tissue between prosthesis and bone in patients with total wrist arthroplasty correlated with the degree of periprosthetic osteolysis (PPO); and to investigate the occurrence of metal particles in the periprosthetic tissue, the level of chrome and cobalt ions in the blood, and the possible role of infectious or rheumatoid activity in the development of PPO. Methods Biopsies were taken from the implant–bone interphase in 13 consecutive patients with total wrist arthroplasty and with at least 3 years' follow-up. Serial annual radiographs were performed prospectively for the evaluation of PPO. We collected blood samples for white blood cell count, C-reactive protein, and metallic ion level. Results A radiolucent zone of greater than 2 mm was observed juxta-articular to the radial component in 4 patients and at the carpal component in 3. The magnitude of the radiolucent zone tended to level out over time. We observed subsidence of the implant in 3 patients on the carpal side and in none on the radial side. The amount of polyethylene and metallic debris was generally small and did not correlate with the width of the radiolucent zone. The blood levels of chrome and cobalt ions were normal. There was no evidence of infectious or rheumatoid activity. Conclusions Polyethylene wear has been accepted as a major cause of osteolysis in total hip arthroplasty, and metallic debris has also been cited to be an underlying cause. However, our hypothesis that polyethylene debris correlated with the degree of PPO could not be confirmed. Also, metallic debris and infectious or rheumatoid activity did not correlate with PPO. Type of study/level of evidence Prognostic I.

Membranous lipodystrophy, also known as Nasu–Hakola disease, is a rare hereditary condition with manifestations in the nervous and skeletal systems. The radiographic appearance of skeletal lesions has been well described in the literature. However, CT and MRI findings of lesions in the bone have not been documented to date. This report describes the radiographic, CT, MRI, and histopathologic skeletal findings in a case of membranous lipodystrophy. With corroborative pathologic findings, a diagnosis of membranous lipodystrophy on imaging allows for appropriate clinical management of disease manifestations.

Intra-articular tumors and tumor-like conditions of the hip are rare. When they occur, they can interrupt normal articular congruency, leading to pain and joint dysfunction. If these conditions result in large osteochondral defects, they pose challenging reconstructive problems in young patients. We describe a case of a 29-year-old man who presented with a 2-year history of right hip pain. Advanced imaging demonstrated an expansile lesion in the region of his ligamentum teres (LT), eroding a significant portion of his femoral head and expanding the cotyloid fossa. He was treated with surgical hip dislocation, excision of the lesion, and femoral head reconstruction with fresh osteochondral (OC) allograft transplantation via press-fit technique. Histologic examination of the mass showed a benign fibromyxoid pseudotumor. Although non-neoplastic masses have been described in almost all organ systems, to our knowledge this is the first description of this entity affecting the native hip joint. It is only the second description of using press-fit OC allografting in the femoral head. This case adds to the body of literature defining symptomatic LT pathology that may benefit from surgical management. It underscores the need to study the ligament further, as the ability to diagnose and treat intra-articular hip pathology has improved with modern imaging and methods of open and arthroscopic hip surgery.

We report a case of an 8-year-old boy who initially presented with a painful subungual mass that was diagnosed as a "glomus tumor" largely based on the clinical presenta tion. Local excision was performed, and the patient remained tumor free for 17 years, after which he experienced three local recurrences and massive pleural metastases within the next 2 years. The tumor was poorly differentiated with small round cells and increased mitotic activity on light microscopy. The precise nature of the tumor was difficult to characterize and was unraveled primarily by immunoperoxidase studies, particularly the diffuse strong positivity of HBA-71 (MIC 2) antibody, also called pe ripheral neuroectodermal tumor-Ewing's sarcoma antigen, which is reported to be fairly specific for these tumors, and the expression of neural markers Leu-7 (HNK-1 ) and neuron-specific enolase. In addition, ultrastructural examination revealed imma ture cell junctions, cell processes, and abundant pools of intracytoplasmic glycogen. Metastatic pleural tumor recurred very rapidly after excision, but showed a dramatic, although short-lasting, response to chemotherapy with cisplatin and etoposide. The thumb is an uncommon location for peripheral neuroectodermal tumor-Ewing's sar coma, and a 17-year, disease-free interval is most unusual for a malignant tumor of this nature. We discuss this case with respect to its unique clinical behavior and in the context of the differential diagnosis of small, round cell neoplasms. Int J Surg Pathol 2(2):147-156, 1994

We report a prospective study of the liner-metal interfaces of modular uncemented acetabular components as sources of debris. We collected the pseudomembrane from the screw-cup junction and the empty screw holes of the metal backing of 19 acetabula after an average implantation of 22 months. Associated osteolytic lesions were separately collected in two cases. The back surfaces of the liners and the screws were examined for damage, and some liners were scanned by electron microscopy. The tissues were studied histologically and by atomic absorption spectrophotometry to measure titanium content. The pseudomembrane from the screw-cup junction contained polyethylene debris in seven specimens and metal debris in ten. The material from empty screw holes was necrotic tissue or dense fibroconnective tissue with a proliferative histiocytic infiltrate and foreign-body giant-cell reaction. It contained polyethylene debris in 14 cases and metal in five. The two acetabular osteolytic lesions also showed a foreign-body giant-cell reaction to particulate debris. The average titanium levels in pseudomembranes from the screw-cup junction and the empty screw holes were 959 micrograms/g (48 to 11,900) and 74 micrograms/g (0.72 to 331) respectively. The tissue from the two lytic lesions showed average titanium levels of 139 and 147 micrograms/g respectively. The back surfaces of the PE liners showed surface deformation, burnishing, and embedded metal debris. All 30 retrieved screws demonstrated fretting at the base of the head and on the proximal shaft. Non-articular modular junctions create new interfaces for the generation of particulate debris, which may cause granulomatous reaction.

Background Rotator cuff repair is a commonly performed procedure, but many of these repairs fail in the postoperative term. Despite advances in surgical methods to optimize the repair, failure rates still persist clinically, thereby suggesting the need for novel mechanical or biological augmentation strategies. Nonresorbable implants provide an appealing approach because patch materials may confer acute mechanical stability and act as a conductive scaffold for tissue ingrowth at the site of the tendon insertion. Hypothesis The polyurethane scaffold mesh will confer greater biomechanical function relative to a nonaugmented repair after 12 weeks in vivo using a chronic ovine model of rotator cuff repair. Study Design Controlled laboratory study. Methods After development of the chronic rupture model, the tensile failure properties of the nonresorbable mesh-augmented repair (n, 9) were compared with those of a surgical control in an ovine model (n, 8). Results Rotator cuff repair with the scaffold mesh in the chronic model resulted in a significant 74.2% increase in force at failure relative to the nonaugmented surgical control (P = .021). Apparent increases in stiffness (55.4%) and global displacement at failure (21.4%) in the mesh-augmented group relative to nonaugmented controls were not significant (P = .126 and P = .123, respectively). At the study endpoint, the augmented shoulders recovered 37.8% and 40.7% of the force at failure and stiffness, respectively, of intact, nonoperated controls. Conclusion Using the previously described chronic rupture model, this study demonstrated that repair of a chronic tendon tear with the polyurethane scaffold mesh provides greater mechanical strength in the critical healing period than that of traditional suture anchor repair. Clinical Relevance This device could be used to enhance the surgical repair of the rotator cuff and consequently improve long-term clinical outcome.

Magnesium is known to have an essential role in determining the properties of bone, but the way in which Mg exerts its actions remains unclear. Although long-term Mg deficiency is known to produce osteopenia, the effects of short-term Mg deficiency have not been established. To test the hypothesis that Mg deficiency results in an altered pattern of initial mineralization and concomitant altered bone properties, the radiographic, histologic, chemical, and mechanical properties of the bones of rats given a Mg-deficient diet were compared to those of rats pair-fed the same diet supplemented with Mg. Short-term Mg-deficiency in the diet of growing rats produced a significant decrease in both the trabecular bone volume and the mineral content of the newly formed metaphysis, a significant increase in the Ca:P ratio, and a slight, but significant increase in hydroxyapatite crystallite size and/or perfection in the metaphysis. Comparable, but not significant, trends were found in the diaphyses. Metaphyseal bone osteocalcin levels were reduced in the Mg-deficient rats and lipid was more easily extracted from their bones. No detectable alterations in radiographic microstructure were noted. Mechanically, a significant decrease in the maximum three-point bend strength of the femurs of Mg-deficient rats was observed. These data support the hypothesis that short-term Mg deficiency affects the pattern of bone mineral formation.

Seventy-one cemented total hip arthroplasties (THAs) were reviewed following removal of the all-titanium alloy femoral stem. Fifty-one hips were primary arthroplasties that failed due to aseptic loosening, 8 were previous revisions with aseptic loosening, and 12 were removed for infection. The average duration of service for the three groups was 4.5 years, 5.0 years, and 3.7 years, respectively. Femoral bone loss in aseptically loose, primary THA was graded as severe in 51%, moderate in 24%, and mild in 20%. Femoral endosteolysis was present in 94%, while acetabular osteolysis was seen in 6%. Histological evaluation of tissues from failed primary arthroplasties revealed polymethyl methacrylate debris in 75% of cases, polyethylene debris in 80%, metal debris in 75%, and chronic inflammatory cells in all cases. Metallic debris was not seen in the failed revision cases and in only 17% of the infected cases. Examination of retrieved femoral components revealed burnishing of the head in all cases, while 71% of stems with aseptic loosening were abraded from the cement. Metal levels from 12 cases averaged 2,111 mg/g of dry tissue (range, 60–11,823); synovial fluid levels from 8 other cases averaged 106 mg/l (range, 22–340). While it is not certain whether metallic particles are a primary cause of loosening or are generated secondarily, their presence seems to accelerate bone loss and loosening.

We performed a prospective study of 30 patients undergoing chronic hemodialysis to determine which of 6 generally available diagnostic procedures provided the most useful information for the assessment of bone disease in hemodialysis patients. The 6 procedures were: routine biochemical measurements, N-terminal parathyroid hormone (N-PTH), radiographic analysis of hands and clavicles, bone density determination by dual photon absorptiometry (DPA), deferoxamine stimulation test, and iliac crest bone biopsy. Serum N-PTH was elevated in 83% of patients but was not significantly associated with abnormalities of other biochemical parameters. No significant relationship was demonstrated between biochemical data and radiographic findings or between biochemical data and bone density by DPA. All patients with abnormal DPA had an elevation of N-PTH; therefore, DPA did not reveal any unsuspected disease. Bone biopsies were done in 20 patients and findings in each were consistent with uremic osteodystrophy, including osteitis fibrosa cystica in 11 patients and aluminum-associated bone disease in 2 patients. Six patients had mixed disease, and 1 patient had osteoporosis. Despite 11 positive deferoxamine tests, bone biopsy revealed aluminum deposition in only 7 of these patients, suggesting extraosseous aluminum accumulation in the remaining 4. Evaluation of the positive and negative predictive accuracies of DPA, x-ray analysis, N-PTH levels, and aluminum bone deposition revealed that normal DPA or x-ray findings do not exclude bone disease, that N-PTH level is a good marker for secondary hyperparathyroidism, and that a negative deferoxamine test excludes aluminum-associated bone disease. Discriminant analysis also reinforced these conclusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypothesis: This study analyzed clinical, radiographic, and histologic data from failed total shoulder arthroplasties (TSAs) to determine factors associated with osteolysis. Materials and methods: From 1985 to 2005, 52 patients (mean age, 61.6 years) underwent revision TSA at a single institution at a mean of 4.3 years after their index surgery. Patients were retrospectively assigned to 2 cohorts based on the presence (n ¼ 10) or absence (n ¼ 42) of osteolysis around their implants on the last prerevision surgery radiographs. Clinical information, associated histopathology from tissues obtained at revision surgery, and polyethylene wear data from the retrieved glenoid components were compared between groups. Results: In the osteolysis group, 20% had screw fixation compared with 2.5% without osteolysis (P ¼ .039). The radiolucency score was significantly higher in the osteolysis group: 12.7 � 2.0 vs 8.7 � 3.7 (P ¼ .003). Wear analysis of the osteolysis group demonstrated significant increases in third-body particles compared with those implants without osteolysis (P ¼ .004). Histology available from retrieved implants demonstrated particulate debris in 62% of patients with osteolytic lesions vs 67% without osteolytic lesions (P > .05). Discussion: Significant differences were found in patients with osteolytic lesions compared with patients undergoing TSA revision surgery without such lesions, specifically with regard to glenoids that used adjuvant screw fixation, the presence of increased radiolucent lines, and an abundance of third-body wear. No significant differences were found in particulate wear debris despite the prevailing notion that osteolysis is associated with particulate debris from implant wear. Conclusion: Screw fixation and third-body wear were associated with osteolysis after TSA. Level of evidence: Level III, Retrospective Comparative Study. 2010 Journal of Shoulder and Elbow Surgery Board of Trustees.

Those aspects of bone histology and histomorphometry that need to be understood by clinicians to put histomorphometry into proper perspective are presented. An increasingly important component of the histologic diagnosis of the metabolic diseases of bone is the quantification of the various histologic features as seen in undecalcified bone biopsies. This article is intended to review some of the histologic features of the metabolic diseases of bone and their corresponding histomorphometric parameters as they are used in diagnosis. The methods of obtaining both direct and derived values as well as the reporting of the results are presented in detail.

Fibroma of tendon sheath is an uncommon benign soft tissue tumor with a predilection for the hand. A unique case involving the scapholunate and radiocarpal joints with bone erosion is reported. The patient presented with a transilluminating mass over the volar radial wrist associated with neuropathy in the superficial radial nerve distribution. Magnetic resonance imaging demonstrated a heterogeneous and lobulated mass with nonspecific signal characteristics closely associated with the scapholunate interval and the volar wrist soft tissues. Histologically it represented a fibroma of tendon sheath. The tumor is discussed and the relevant literature is reviewed.

Transport of nutrients, cytokines, pharmacologic agents, and matrix components through articular cartilage is critical for the viability and structural integrity of the tissue. To understand the role of the extracellular matrix in regulating this process, we measured the diffusivity of three uncharged solutes of different molecular size (glucose, MW 180; inulin, MW 5000; dextran, MW 70,000) into intact cartilage and cartilage that had its proteoglycan (PG) component removed. Solute diffusivity was measured by performing transient (nonsteady state) one-dimensional diffusion tests using radiolabelled solutes. Compared to intact cartilage, the diffusivity of glucose was unchanged after PG removal, inulin was unchanged but dextran inereased by 1.7 times after 71% PG removal, and both inulin and dextran increased by 1.6 and 2.0 times, respectively, after 93% PG removal. The diffusivities of inulin and dextran were inversely proportional to the PG content. While no change was found in the tissue's bulk fluid content. PG depletion resulted in an increase in fluid content in the upper regions of the tissue and a decrease in the lower regions. These results indicate that in intact tissue small uncharged solutes have free mobility through the inter-molecular and intra-molecular PG volumes, larger molecules have limited intra-molecular mobility, and very large molecules are excluded from the intra-molecular space.

Neuropathic arthropathy occurs most often in the weight-bearing joints in association with diseases in which there is impairment of the efferent sensory input from joint receptors. This leads to characteristic fragmentation of the articular cartilage and osteophytosis. These changes also are seen in the spine in association with syphilis and fractures of the spine2,15,19,22,24. One of the most difficult problems in orthopaedics is the treatment of a Charcot joint, especially when the goal is to obtain a solid fusion. The purpose of this report is to describe the treatment of kyphoscoliosis associated with spinal arthropathy in a forty-five-year-old man who had Charcot-Marie-Tooth disease, a hereditary motor and sensory neuropathy. A forty-five-year-old man was admitted to the hospital with a two-year history of progressive left-sided posterior thoracic and intercostal pain. Narcotic medications were necessary to relieve the pain, which had prevented the patient from playing and teaching the trumpet for six months. A review of the records revealed that the patient had been diagnosed as having type-I hereditary motor and sensory neuropathy (Charcot-Marie-Tooth disease) when he was nineteen years old. During adolescence, he had had a gradual onset of weakness and atrophy of both legs, atrophy of the intrinsic muscles of the hands, and a weak grip. As a teenager, he had been managed with a Milwaukee brace because of thoracic scoliosis. Additional details regarding the treatment with the brace were not available. When the patient was three years old, he had had a positive tuberculin test and had been hospitalized for one week. He was unable to provide additional details regarding the treatment. His father and paternal uncle also had Charcot-Marie-Tooth disease. He had had two episodes of pneumonia before the initial evaluation at our clinic and was being managed …

The authors evaluated three cases of soft tissue chondromas in patients aged 55, 57, and 78 years. Two of the lesions occurred in the foot and one in the hand. All three patients had long histories (over 1 year) of a palpable mass and all three had roentgenograms showing well-demarcated lobulated soft tissue lesions with both central and peripheral calcifications. Recognition of this rare benign chondroid lesion on imaging studies is significant since it may be misinterpreted as an aggressive lesion or a primary synovial abnormality.

We have reported the case history of a 72-year-old woman who was on hemodialysis for 15 years. Her course was marked by many of the musculoskeletal complications of ESRD including CTS, stromal amyloid deposition of synovium, amyloid cystic degeneration of bone, and inflammation of the synovium due to the deposition of calcium oxalate and calcium pyrophosphate microcrystals. She also had evidence of metabolic bone disease: moderate osteoporosis related to secondary hyperparathyroidism and osteomalacia related to aluminum deposition at the mineralization front. The pathological and radiological findings associated with her bone disease are described.

In a patient with a disrupted silicone prosthesis, the presence of a swollen articulation should suggest the presence of silicone-induced reactive synovitis. Diagnosis of the entity rests on the identification of particulate matter by polarized microscopy and/or scanning electron microscopy--studies that will not be performed routinely unless the diagnosis is suggested preoperatively. The case presented is that of a 68-year-old woman in whom a silicone elastomer trapeziometacarpal prosthesis had been implanted 5 years previously. Painful swelling had ensued, and biopsy confirmed the diagnosis.

A 63-year-old women with a 12-year history of rheumatoid arthritis (RA) had calcific deposits in the periarticular soft tissues with subsequent involvement of the medullary canals of adjacent bones. Except for the RA, there was no evidence of other abnormalities of the bones or mineral homeostasis. Chemical analyses of the deposits identified the crystalline material as apatite. Although the deposition of apatite in the soft tissues of RA is known to occur rarely, this is the first known case of intraosseous apatite deposition.

This study was designed to determine the sensitivity of magnetic resonance imaging (MRI) in the detection of ischemia or avascular necrosis after displaced intracapsular hip fractures. Magnetic resonance imaging was performed on 20 patients who had hemiarthroplasties performed for Garden IV intracapsular fractures. Sixteen patients had in vivo coronal T1-weighted spin-echo imaging from the day of injury to 60 days after fracture. After hemiarthroplasty, all 20 resected femoral heads had in vitro T1 imaging. A coronal slab was then cut from the center of the femoral head and studied histologically. The in vivo, in vitro, and histologic slides correlated well. None of the MRI images depicted areas of ischemia or avascular necrosis in patterns observed in nontraumatic necrosis. Avascular bone can be indistinguishable from normal bone in both MRI and histologic sections for a considerable amount of time after vascular insult. Magnetic resonance imaging is not a prognosticator for posttraumatic osteonecrosis in the first two weeks after fracture.

The results of magnetic resonance (MR) imaging in six patients with transient osteoporosis of the hip were reviewed. Short TR/TE (repetition time/echo time) images demonstrated diffusely decreased signal intensity in the femoral head and intracapsular region of the femoral neck. Increased signal intensity was noted with progressive T2 weighting. Bone biopsies were performed in four patients. Histologic findings were nonspecific and included fat necrosis, marrow edema, increased bone resorption, and reactive bone formation. Repeat MR scans in two patients, performed six and eight months after the initial scans, showed an almost complete return to normal marrow signal. All patients became asymptomatic without bony deformity. In the appropriate clinical setting, MR scanning can aid in the diagnosis of transient osteoporosis as the cause of a painful hip.

A prospective study was undertaken to quantitate metallic and cement debris in 12 consecutive patients with femoral endosteolysis (FE) and aseptic loosening of a cemented total hip arthroplasty. The mean interval between primary and revision surgery was 9.6 years. The average time to onset of FE was 8.9 years. There were four stems each of cobalt-chromium (Co-Cr), stainless steel (SS), and titanium alloy. At revision, tissue was retrieved from FE, the femoral bone-cement pseudomembrane, and the joint pseudocapsule. Histology of these tissues was studied using light and polarized microscopy. Metal and barium levels were measured by atomic absorption spectrophotometry. A histiocytic reaction and particulate cement debris were seen in every case. Polyethylene wear debris was noted in 11 of 12 cases (92%), and metallic debris in four cases (33%). Detectable metal levels were found in the FE in all cases. Metal levels were on average 2.5 times higher in FE than in femoral pseudomembrane, and 4.2 times higher than in joint pseudocapsule. This difference was statistically significant for the Co-Cr and SS groups. Barium levels in areas of FE were on average 1.7 times and 42.4 times higher than in femoral pseudomembrane and joint pseudocapsule, respectively. The difference seen between the FE and the joint pseudocapsule tissue was significant for all three alloy groups. The authors' data demonstrated higher metal and barium levels in FE than in the other tissue sites. Polyethylene and cement debris were noted in nearly every case. Cement, polyethylene, and metallic particulate wear debris may contribute to the pathogenesis and progression of FE.

To investigate the hypothesis that an association exists between the presence of metallic particulate or ionic debris released from the components of a total hip replacement and the histologic reaction in the surrounding tissues, cobalt, chromium, nickel, and molybdenum levels were measured in periarticular tissue from 22 individuals who had revision surgery. Total tissue content of the four elements (averaged per case) ranged from 2.7 to 250 micrograms of metal per gr of dried tissue (mean, 39 micrograms/gr); however, within each case, the tissue-metal content varied more widely. The highest total tissue-metal contents occurred in cases revised for infection. Fibrosis, histiocytic reaction, hemorrhage, and necrosis were the most frequent histologic findings. Polyethylene and cement particles each appeared in approximately half of all sections, while microscopic metal particles were seen only in tissues from the infected hips. Tissue-metal content did not correlate with the histologic findings, with any of the demographic variables, nor with duration of implantation. Ratios of the individual constituent elements generally reflected the cobalt-chromium alloy composition, suggesting that metal debris was present predominantly as wear particles. Only for tissues with very low metal contents did departures of these ratios indicate the presence of ionic corrosion products. The extremely low metal contents measured in many cement-bone interfacial tissues and the few metal particles found histologically suggest that metal particles may have been less important in inflammatory reaction and loosening than cement or polyethylene particles.(ABSTRACT TRUNCATED AT 250 WORDS)

A patient undergoing hemodialysis is described in whom osteomalacia developed despite protracted treatment with calcitriol. Appropriately stained biopsy sections exhibited iron at all marrow-osteoid interfaces and a small fraction of trabecular mineralization fronts. Aluminum, the metal usually associated with osteomalacia in patients undergoing hemodialysis, was not histochemically demonstrable, even though spectrophotometrically measured bone aluminum content was substantial. These observations suggest two interpretations: iron may have caused osteomalacia through effects on bone cells and at mineralization fronts; alternatively, aluminum may have caused osteomalacia while remaining histochemically undetectable. It is possible that both metals exerted toxic effects simultaneously.

The performance of carbon fiber-reinforced ultra-high molecular weight polyethylene was compared with that of plain (non-reinforced) polyethylene on the basis of the damage that was observed on the articulating surfaces of retrieved tibial components of total knee prostheses. Established microscopy techniques for subjectively grading the presence and extent of surface damage and the histological structure of the surrounding tissues were used to evaluate twenty-six carbon fiber-reinforced and twenty plain polyethylene components that had been retrieved after an average of twenty-one months of implantation. All of the tibial components were from the same design of total knee replacement. The two groups of patients from whom the components were retrieved did not differ with regard to weight, the length of time that the component had been implanted, the radiographic position and angular alignment of the component, the original diagnosis, or the reason for removal of the component. The amounts and types of damage that were observed did not differ for the two materials. For both materials, the amount of damage was directly related to the length of time that the component had been implanted. The histological appearance of tissues from the area around the component did not differ for the two materials, except for the presence of fragments of carbon fiber in many of the samples from the areas around carbon fiber-reinforced components.

The purely epithelioid malignant peripheral nerve sheath tumor (PNST) is a rare form of PNT possibly first described by McCormack et al. in 1954. This tumor type is distinguishable from the glandular PNT and PNT with differentiated neuroepithelium (medulloepithelioma and neuroepithelioma) and differs from the ordinary epithelioid PNT because of the absence of a spindle cell component typical of malignant PNSTs. The two examples of purely epithelioid malignant PNT we describe arose in the popliteal fossa from the sciatic and tibial nerves of men with no definite evidence of von Recklinghausen's neurofibromatosis. Both tumors were partly mucinous, and so closely mimicked carcinoma and a few non-neurogenic myxoid sarcomas histologically that their final classification depended upon proof of a neural origin.

Les deux cas decrits sont secondaires a un defaut du polyethylene moule renforce par des fibres de carbone. Une usure extreme dans un cas et une fracture dans l'autre. Les deux echecs resultent de la mauvaise consolidation entre les fibres de carbone et le polyethylene au moment de la fabrication

A carcinosarcoma of the cardia of stomach is reported. This is a rare entity which is of further interest because of an associated but distinctly separate carcinoid tumor. The main tumor showed distinct adenocarcinomatous and spindle cell components which collided in many areas. The sarcomatous nature of the spindle cell component was confirmed by ultrastructural studies. We have reviewed the literature and have not found a similar case.

A positive family history is considered a risk factor for osteoporosis (OP) although the genetic or biochemical basis for this relationship remains undefined. Various mutations affecting normal synthesis of type I collagen have been reported in osteogenesis imperfecta (OI), a heritable disorder of connective tissue. Family A, in which the proband and a daughter are afflicted with OP and idiopathic scoliosis was examined for defects in collagen metabolism. Dermal fibroblast cultures were established to investigate de novo collagen synthesis. SDS-PAGE revealed an abnormally migrating alpha 2(I) chain and procollagen in two generations. Examination of the kinetics of type I collagen pCN-propeptide processing demonstrated a rate 2x control in the proband. The phenotype family A is not OI. It shares features with families BC, having familial clustering of OP. However, collagen synthesis was not abnormal in family BC. These data suggest that in family A the alpha 2(I) structural defect may be related to defective skeletal matrix formation.

Patiente de 29 ans, presentant des douleurs et une limitation des amplitudes, ablation chirurgicale d'un osteochondrome, situe dans un kyste poplite, evoluant depuis 10 ans

An unusual case of small cell anaplastic carcinoma of the lung, presenting as a pelvic mass, is presented. Histochemical and electron microscopic findings confirmed the diagnosis. The pathologic features and unique clinical characteristics are discussed with comments on the topic of metastatic ovarian tumors.

We report the histological findings seen in the lymph nodes draining the sites of large joint prostheses. Two patients underwent multiple prosthetic joint replacements. In one patient, the regional lymph nodes were enlarged during the revision of a total hip prosthesis, and a representative lymph node was resected. The other patient had undergone a pelvic lymph node dissection as part of a staging procedure for prostatic carcinoma. By light microscopy, the lymph nodes from both patients showed markedly dilated nodal sinuses filled with macrophages containing abundant eosinophilic, PAS-positive, granular material. Polarization microscopy revealed needle-like particles within the cytoplasm of the macrophages. We believe that the histological appearance of the lymph nodes represents a florid foreign body reaction to fragments of polyester or polyethylene derived from the articulating surfaces of the joint prostheses and transported to the regional lymph nodes via the lymphatic circulation. Sinus histiocytosis seen in the lymph nodes draining the sites of joint prostheses may resemble, and must be distinguished from, other conditions invoking a sinus pattern of lymphadenopathy, as well from benign and malignant diseases that involve the lymph nodes in a pattern mimicking sinus histiocytosis.

Eleven lipomatous tumors of the extremities (7 liposarcomas, 4 lipomas) were evaluated radiographically by several modalities, including computed tomography (CT) in all lesions. Lipomas were seen on CT scan as well delineated, homogeneous masses with negative attenuation coefficients ranging from -95 to -160. Liposarcomas were inhomogeneous, multilobulated, poorly delineated lesions located exclusively in the subfascial or intramuscular planes, with an intermediate range of attenuation coefficients between those of fat and those of muscle. In six of seven liposarcomas, definite low density areas were identified by attenuation coefficient as fatty tissue. Magnetic resonance imaging (MRI) was obtained in two patients and was helpful in defining the extent of the tumors and their relationship to vital structures, but MRI could not differentiate benign from malignant tissue. Computed tomography is recommended as the cornerstone in the initial radiographic evaluation of growing or painful lipomatous soft tissue masses of the extremities.

Occurrence of giant cell reparative granuloma (GCRG) outside the jaw, skull, or facial bones is unusual. Three recent cases of GCRG occurring in the hand are presented. This lesion appears on radiographs as a lucent, expansile defect in bone, similar in appearance to enchondroma, giant cell tumor of bone, aneurysmal bone cyst, or brown tumor of hyperparathyroidism. Histologically, GCRG is characterized by spindle-shaped, fibroblastic stoma with scattered, small, angulated giant cells and areas of osteoid formation around foci of hemorrhage. Establishing the pathologic diagnosis is frequently difficult. Misdiagnosis occurred in approximately half of the reported cases and in one of our cases. The typical clinical presentation is that of localized pain and swelling. GCRG is not a neoplastic disorder; however, it recurred locally in a third of the reported cases. Recommended treatment for GCRG is thorough removal of the diseased tissues and grafting of autologous bone.

Six patients with poorly defined chronic hip symptoms (length of time from initial symptoms to definitive diagnoses ranged from four months to three years) were eventually found to have benign lesions in the region of the acetabular fovea. All of these patients had seen multiple physicians including orthopedic surgeons before the definitive diagnosis was made. Four lesions were not visualized on routine roentgenographs. Various imaging modalities were necessary to demonstrate and localize these lesions. Excision through an anteromedial approach (Ludloff) in five cases required minimal dissection, operative time, and blood loss. The approach does not compromise definitive surgery (external or internal hemipelvectomy) in the unlikelihood that the lesion is found to be malignant.