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ABSTRACT: In 1079 consecutive patients undergoing total hip arthroplasty between 1984 and 1992, complications of thromboembolic disease and related anticoagulation were reviewed for 6 months after hospital discharge, including cost data. Of 347 patients having venograms, 78 (22.5%) had positive results and 269 (77.5%) had negative results for deep venous thrombosis. In patients with negative venograms, 3 (1.1%) were readmitted with 2 symptomatic deep venous thromboses and nonfatal pulmonary embolism. There were no readmissions among the 55 patients who had venographically evident deep venous thrombosis diagnosed and treated with outpatient warfarin. Overall, 3 of 324 (0.9%) patients with true positive or negative venograms were readmitted for complications of thromboembolic disease. In contrast, 12 of 732 (1.6%) patients not receiving contrast venography were readmitted, including 9 (1.2%) deep venous thromboses and 3 (0.4%) nonfatal pulmonary embolisms. Four of 23 patients (17.4%) with untreated calf deep venous thrombosis suffered 2 nonfatal pulmonary embolisms resulting in readmission and 2 fatal pulmonary embolisms outside the hospital. Untreated calf deep venous thrombosis after total hip arthroplasty represents a significant threat of extension to more proximal veins and distant embolization. Routine thromboembolic disease prophylaxis combined with screening contrast venography and selective therapeutic anticoagulation is effective in preventing late thromboembolic disease complications and, compared with a strategy of extended prophylaxis for all, is cost effective management by reducing exposure of the elderly population to outpatient anticoagulant therapy.
Clinical Orthopaedics and Related Research 01/1997; · 2.53 Impact Factor
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ABSTRACT: Eighty-six hips in eighty-five patients who were considered to be at risk for heterotopic ossification following a total hip arthroplasty were prospectively randomized or assigned to one of two treatment groups that received a single 800-centigray dose of limited-field radiation either preoperatively (Group I) or postoperatively (Group II). The risk factors for postoperative heterotopic ossification included previous heterotopic ossification following an operation about the hip, hypertrophic osteoarthrosis or post-traumatic osteoarthrosis characterized by the presence of extensive osteophytes, radiographic evidence of diffuse idiopathic skeletal hyperostosis, and ankylosing spondylitis. The hips in Group I were irradiated within 6.1 hours before the operation and those in Group II, within 51.3 hours after the operation. Either extra-field ossification or heterotopic ossification was observed in forty-one (48 per cent) of the eighty-six hips, thereby confirming the high risk for the population in this study. After a minimum duration of follow-up of six months, thirty-seven (76 per cent) of the forty-nine hips that had been treated with preoperative irradiation exhibited no new heterotopic ossification and eleven, progression to grade-I or II ossification. The remaining hip in that group was in a woman who had Paget disease as well as previous grade-IV (ankylosing) heterotopic ossification about the ipsilateral hip; heterotopic ossification progressed from grade II on the radiographs made immediately after the index revision procedure to grade III at the most recent follow-up assessment. Of the thirty-seven hips that had been treated with postoperative irradiation, twenty-seven (73 per cent) exhibited no new heterotopic ossification and nine had progression from grade-0 to grade-I ossification. The remaining hip in that group was in a man who had Parkinson disease and previous grade-III ossification about the ipsilateral hip; heterotopic ossification progressed from grade III immediately post-operatively to grade IV at the time of the most recent evaluation. Extra-field ossification was identified in twelve (24 per cent) of the forty-nine hips that had been irradiated preoperatively compared with three (8 per cent) of the thirty-seven hips that had been irradiated postoperatively (p = 0.05). Extra-field ossification was not associated with clinical symptoms of bursitis of the greater trochanter in any hip. Three of the ten hips that had a revision operation subsequently had a non-union of the greater trochanter; all three had been treated with preoperative irradiation. The findings of the present study suggest that pre-operative irradiation is effective for the prevention of heterotopic ossification following total hip arthroplasty and that it eliminates the discomfort and morbidity that are associated with conventional postoperative treatment. Furthermore, the efficacy of preoperative irradiation suggests that osteogenic precursor cells that are active in this process are derived from the local tissues within the operative field rather than from distant blood-borne cell lines.
The Journal of Bone and Joint Surgery 07/1996; 78(6):870-81. · 3.27 Impact Factor
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ABSTRACT: A prospective, randomized trial was conducted to compare the effectiveness and safety of warfarin given in two regimens in prevention of venous thrombosis after total knee replacement. Adult patients scheduled for primary or revision total knee replacement were randomly assigned to receive either a "two-step" warfarin regimen beginning 10-14 days pre-operatively or, alternatively, to begin warfarin the night before surgery. Post-operatively, the dose was adjusted in both groups to achieve a target International Normalized Ratio (INR) of 2.2 and prophylaxis was continued until venography on post-operative days five through nine. Bleeding was assessed by surgical blood loss, transfusion requirements, changes in hematocrit, and clinically identified bleeding complications. The occurrence of deep vein thrombosis was nearly the same in the two treatment groups, 39% in patients randomized to the two-step regimen as compared to 38% in those beginning the night before surgery. The occurrence of proximal vein thrombosis was also similar, 5% versus 7% (p = NS). Patients in the two-step group received 1.33 +/- 1.26 transfusions compared to 0.95 +/- 1.22 in the night before group (p < 0.05) and also had a lower nadir post-operative hematocrit of 26.7 +/- 3.1 as compared to 28.5 +/- 3.2 (p < 0.0001). Major bleeding complications were associated with excessively prolonged INRs and occurred in five patients in the two-step group and two in the night before group. Patients in both groups who developed thrombosis had a significantly lower INR on post-operative days two and three compared to those without thrombosis. We conclude that a prophylactic warfarin regimen for prevention of deep vein thrombosis after total knee replacement beginning the night before surgery is more convenient and may be associated with less bleeding than a regimen beginning warfarin 10-14 days pre-operatively. Careful control of anticoagulant intensity is needed to achieve maximum effectiveness and avoidance of bleeding complications.
Thrombosis and Haemostasis 05/1996; 75(5):706-11. · 5.04 Impact Factor
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ABSTRACT: The biomechanical effects of extension metacarpal osteotomy on contact pressures in the trapeziometacarpal joint during lateral pinch were studied in 20 anatomic specimens using pressure-sensitive film. The gross appearance of joint surfaces was classified by severity of arthritic disease and correlated with specimen x-ray films taken before the osteotomy. Extension metacarpal osteotomy effectively unloaded the palmar contact area in nonarthritic and moderately arthritic specimens; primary contact areas and zones of peak pressure were shifted from the diseased palmar compartment to the normal dorsal compartment. In contrast, the pathologically congruent contact pattern seen in end-stage osteoarthritic joints was unaffected by osteotomy. The data demonstrate the efficacy of extension metacarpal osteotomy in unloading the palmar contact areas of normal and moderately arthritic joints but provide no biomechanical rationale for metacarpal osteotomy as originally described in treatment of advanced trapeziometacarpal osteoarthritis.
The Journal Of Hand Surgery 02/1996; 21(1):16-23. · 1.35 Impact Factor
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ABSTRACT: Ninety-eight consecutive primary total knee arthroplasties (TKAs) in 70 patients were retrospectively evaluated for heterotopic ossification (HO). A radiographic classification was devised based on the extent and location of the ectopic bone. Twenty-five knees (26%) in 19 patients developed HO. Eight of 11 patients (73%) with preexisting heterotopic bone at other sites developed HO in the index knee. Multivariate analysis demonstrated that advanced HO was associated with restricted knee motion. Eight knees with advanced HO had a mean 14 degrees decrease in postoperative, as compared with preoperative, knee flexion (P < .05). For all patients with HO, mean lumbar spine bone mineral density (BMD) was significantly elevated compared with a matched control group not developing HO (P < .05). Heterotopic ossification following primary TKA correlates with a limitation of postoperative knee flexion and is predicted by increased lumbar BMD. Preoperative measurement of spinal BMD may identify those patients at risk for HO and allow for the institution of preoperative prophylaxis and modification of postoperative rehabilitation to optimize functional outcome following TKA.
The Journal of Arthroplasty 09/1995; 10(4):413-9. · 2.38 Impact Factor
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V D Pellegrini
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ABSTRACT: The frequency and distribution of idiopathic osteoarthritis (OA) in the upper extremity has been observed to vary considerably among different races. This study seeks to investigate the prevalence of trapeziometacarpal OA and differences in pathologic anatomy in comparable populations of Caucasian and Asian peoples. Sixty-one postmortem Japanese, Chinese and Indian specimens were examined for integrity of both the stabilising soft tissue structures and articular surfaces. Chondromalacia and eburnation were assessed by location in the joint relative to previously described patterns of disease in Caucasian specimens. Among 35 Japanese specimens, 23 (66%) were found to have completely normal joint surfaces, 5 (14%) had chondromalacia limited to the dorsal surfaces, 2 (6%) had chondromalacia on the volar surfaces, and 5 (14%) exhibited eburnation consistent with advanced degenerative disease. A similar distribution was noted for the 22 Chinese specimens. When present, the pattern of arthritic disease was identical to that seen in Caucasian joints; eburnation of surfaces was only seen in the volar compartment and dorsal joint cartilage was typically spared. Detachment of the volar beak ligament was evident in all joints with eburnation, and degeneration of the metacarpal insertion was present in specimens with volar chondromalacia. The concavoconvex configuration of the joint surfaces was more shallow in Japanese and Chinese specimens than comparable Caucasian joints. A similar study of Caucasian joints demonstrated only 25% with normal articular surfaces, 10% with dorsal chondromalacia as a lesion indicative of physiologic aging, 15% with volar chondromalacia as a prearthritic progressive lesion, and 50% with eburnation indicative of end-stage arthritic disease. Based upon the study of postmortem material, the anatomical prevalence of trapeziometacarpal joint osteoarthritis is considerably less in the Japanese and Chinese than in the Caucasian race.(ABSTRACT TRUNCATED AT 250 WORDS)
Annals of the Academy of Medicine, Singapore 08/1995; 24(4 Suppl):21-5. · 1.25 Impact Factor
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ABSTRACT: Biopsy specimens of cartilage and subchondral bone were obtained from the weight-bearing dome of the acetabulum in twelve elderly patients who were having a revision of a hemiarthroplasty of the hip because of pain. Biopsy specimens of acetabular cartilage and subchondral bone were also obtained from eight patients of comparable age who were having a primary hemiarthroplasty for a displaced fracture of the femoral neck; these served as the control specimens. The specimens were stained with hematoxylin and eosin for the initial histological assessment of cartilage structure and cellularity as well as the integrity of the tidemark. Safranin-O and toluidine-blue stains were used to assess proteoglycan content. A histological grading scale was employed for comparative analysis of samples. The joint space of the hip was measured on the radiographs that were made before the revision and was correlated with the histological grade. Review of the histological specimens demonstrated considerable degeneration of acetabular cartilage in the patients who were having a revision of a hemiarthroplasty as compared with that in the age-matched control patients who were having a primary hemiarthroplasty. The progression in the severity of the degeneration correlated directly with the duration of articulation of the implant with the acetabulum. All six of the patients in whom the implant had been in situ for more than five years, and in whom the femoral stem was determined to be stable at the operation, had nearly complete loss of cartilage as seen on histological examination.(ABSTRACT TRUNCATED AT 250 WORDS)
The Journal of Bone and Joint Surgery 07/1995; 77(6):877-82. · 3.27 Impact Factor
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ABSTRACT: Twenty-four thumbs of twenty-two patients were evaluated at an average of nine years (range, eight to eleven years) after a ligament reconstruction-tendon interposition arthroplasty for osteoarthrosis at the base of the thumb. The same group had also been examined two and six years postoperatively. The procedure had been performed as a primary operation in twenty-one thumbs and as a revision of a failed implant arthroplasty in three. Twenty-one (95 per cent) of the twenty-two patients had excellent relief of pain and were satisfied with the outcome. The average grip strength increased ten kilograms (p < 0.005), reflecting a 93 per cent improvement compared with the preoperative values. Similarly, the average tip pinch strength steadily improved, with an increase at the most recent examination of nearly one kilogram (p < 0.005) (65 per cent improvement). Improvements in the average key pinch strength, however, were first noted at the six-year follow-up examination and then tapered slightly; the most recent values reflected an average gain of 34 per cent but were not significantly different from the preoperative values. The tip of twenty-two (92 per cent) of the twenty-four thumbs was able to touch the base of the little finger, and the most recent average web angle (40 degrees) was unchanged from the value at the two-year follow-up examination. Stress radiographs showed an average subluxation of the metacarpal base of 11 per cent at nine years compared with 7 and 8 per cent at two and six years, respectively. Similarly, these radiographs demonstrated an average loss of height of the arthroplasty space of 13 per cent at nine years compared with 11 per cent at both of the earlier follow-up examinations. This modest deterioration of radiographic parameters was not predictive of an unsatisfactory outcome. The ligament reconstruction-tendon interposition arthroplasty provided a stable and functional reconstruction of the thumb, resulting in excellent relief of pain and a significant increase in strength for as long as eleven years after the procedure.
The Journal of Bone and Joint Surgery 04/1995; 77(3):346-55. · 3.27 Impact Factor
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ABSTRACT: The purpose of this study was to compare the density of periprosthetic bone about titanium and cobalt-chromium stems that had been inserted without cement. The analysis was done, three to four years after a total hip arthroplasty, in a retrospectively matched cohort of thirty patients. Fifteen patients had a stem that was collarless, proximally coated, and made of titanium; the other fifteen had a stem of similar design that was made of cobalt-chromium. The criteria for selection in the study included an excellent clinical and radiographic result and separately calculated modified Harris and Mayo hip scores of more than 94 points. All stems had radiographic evidence of osseous ingrowth. A comparison of the bone-mineral density about the two different types of stem with dual-energy x-ray absorptiometry revealed a significant difference only along the calcar of the femur. There was no significant difference about the remaining, preponderant portion of the proximal part of the femur. Our data suggest that the difference in the modulus of elasticity between the two types of stem had little effect on the loss of bone-mineral density in most of the proximal part of the femur after arthroplasty without cement.
The Journal of Bone and Joint Surgery 03/1995; 77(2):231-9. · 3.27 Impact Factor
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The Lancet 03/1995; 345(8948):527. · 38.28 Impact Factor
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ABSTRACT: The authors studied the use of epidural anesthesia prolonged to 48 hours of epidural analgesia in 120 total hip arthroplasty patients in a case-control fashion. One half of the patients received prolonged epidural anesthesia, while the other matched half received general endotracheal anesthesia. Venograms were obtained after surgery and graded in blind fashion by a single radiologist. The overall incidence of deep venous thrombosis in the epidural versus general anesthetic groups was 23 (14 of 60 patients) versus 40% (24 of 60) (P < .05). There was an identical incidence--8.3% (5 of 60 patients)--of proximal thrombosis in the two groups, and all of the difference in the overall rates of thrombosis occurred in the calf. Fifteen percent (9 of 60 patients) of the epidural patients and 31.6% (19 of 60) of the general anesthetic patients demonstrated this finding (P < .05). Of the 10 proximal clots, 8 (80%) were found in the operative leg, while only 29 (59.2%) of the 49 calf clots were found in the operative leg. Prolonged epidural anesthesia significantly decreases the incidence of deep venous thrombosis after total hip arthroplasty, with its most apparent benefit on calf vein thrombosis secondary to its hyperkinetic effect on lower limb blood flow. The observation that it has no demonstrable effect on the prevention of proximal thrombosis and our finding that the majority of proximal clots are in the operative leg suggest that thrombi in the thigh may be the result of a different primary pathogenic mechanism that is more related to endothelial injury than to changes in viscosity or blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)
The Journal of Arthroplasty 12/1994; 9(6):611-6. · 2.38 Impact Factor
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ABSTRACT: Histologic examination of synovial tissue from the revisions of six cobalt-chrome and six titanium alloy total knee arthroplasties was made. Aseptic polyethylene wear-through had resulted in metal-on-metal contact of bearing surfaces and was the primary indication for revision surgery in all knees. The cobalt-chrome alloy prostheses failed at the femorotibial articulation at a mean of 92 months, while the titanium prostheses experienced patellofemoral failure at a mean of 39 months after implantation. Neither alloy was associated with any meaningful inflammatory infiltrate, and cement debris was comparable in both groups. Titanium alloy knees generated significantly more metallic debris than the cobalt-chrome alloy knees (P < .001). Cobalt-chrome alloy knees had more polyethylene debris (P < .01) and a greater number of histiocytes (P < .005). Titanium and polyethylene debris were associated with a prominent giant cell reaction. Titanium exhibited greater abrasive wear and elicited a different cellular response than cobalt-chrome under conditions of polyethylene failure allowing metal-on-metal contact. The variability of this foreign body reaction may be due to important differences in particle size and number, as well as in the material properties of the two alloys.
The Journal of Arthroplasty 07/1994; 9(3):291-304. · 2.38 Impact Factor
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ABSTRACT: Post-traumatic radioulnar synostosis can have a profound effect on upper extremity function. Prior reports of excision, with and without interposition material, have demonstrated frequent recurrence and disappointing results. Based on a favorable experience with radiation prophylaxis of heterotopic ossification following total hip arthroplasty, this modality has been used in the management of post-traumatic forearm synostosis. Four cases using excision of bony synostosis followed by single-fraction, low-dose (800 cGy), limited-field irradiation are presented. With a follow-up period of 1-4 years after excision and irradiation, all four patients had total arcs of forearm rotation between 115 degrees and 120 degrees. Each patient noted sustained functional improvement, and there was no x-ray film evidence of recurrent synostosis formation. Single fraction irradiation did not require ongoing patient compliance nor did it complicate rehabilitative efforts. Furthermore, soft tissue and bony healing were not impaired.
The Journal Of Hand Surgery 06/1994; 19(3):394-401. · 1.35 Impact Factor
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ABSTRACT: Biochemical analysis was performed on hyaline cartilage from four distinct quadrants in surgically harvested osteoarthritic thumb trapeziometacarpal joints and both normal and osteoarthritic cadaver specimens. Chondromalacic surfaces in the palmar contact areas of arthritic specimens were characterized by preferential loss of glycosaminoglycan, retention of collagen, and a shift in glycosaminoglycan subspecies as indicated by an increasing chondroitin sulfate/keratan sulfate ratio. In contrast, articular cartilage from the dorsal portion of arthritic joints biochemically resembled that from both the adjacent normal surfaces of the scaphoid and trapezoid facets and normal postmortem specimens. No significant difference was noted between the biochemical profiles of osteoarthritic surgical specimens and arthritic cadaver specimens. Such selective glycosaminoglycan depletion localized to the contact areas of the joint suggests an interdependent relationship between mechanical factors and biochemical matrix degradation in production of the cartilage lesion of trapeziometacarpal osteoarthritis.
The Journal Of Hand Surgery 02/1994; 19(1):70-8. · 1.35 Impact Factor
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ABSTRACT: Regional variation in the surface ultrastructure of hyaline cartilage in the osteoarthritic trapeziometacarpal joint was studied by means of scanning electron microscopy. Articular surface degeneration on intact osteochondral specimens was analyzed and correlated with known patterns of gross, histologic, and biochemical disease. The earliest changes were observed in the tangential surface lamina and occurred in areas of chondromalacia in the palmar contact area of the joint. Progressive disruption of this superficial fibrillar layer of the articular cartilage was followed by disorganization of the underlying chondrocytes and matrix. In palmar regions with more advanced chondromalacia and loss of eosinophilic staining, free cellular elements and craters 20-30 microns in diameter, resembling empty chondrocyte lacunae, appeared in conjunction with the absence of any tangential surface meshwork. Eburnated areas demonstrated no fibrillar or cellular elements. Disruption of the protective surface lamina of trapeziometacarpal articular cartilage occurs in a geographic pattern corresponding to joint contact areas and regions of selective biochemical decomposition of proteoglycan matrix. These observations support an interdependent relationship between mechanically induced abrasive surface wear and biochemical matrix degradation in the production of the cartilage lesion of trapeziometacarpal osteoarthritis.
The Journal Of Hand Surgery 02/1994; 19(1):79-85. · 1.35 Impact Factor
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Contemporary orthopaedics 01/1994; 27(6):551-77.
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V D Pellegrini
The Journal Of Hand Surgery 12/1993; 18(6):1093-4. · 1.35 Impact Factor
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ABSTRACT: Thumb metacarpophalangeal (MCP) joint dislocations are infrequent injuries, and palmar dislocations rarely occur. The following is a case report of a complex palmar dislocation of the thumb MCP joint that demonstrates the unique physical finding of paradoxical flexion of the MCP joint (and interphalangeal joint extension) in conjunction with the patient's active attempt to extend the MCP joint. This finding proved to be indicative of extensor pollicis tendon displacement palmar to the MCP joint. This soft-tissue incarceration necessitated open reduction. A careful clinical examination is essential for an accurate evaluation of these injuries. Thus, a satisfactory clinical outcome can be attained with strict attention to the intraoperative pathology and technique of repair.
Clinical Orthopaedics and Related Research 12/1993; · 2.53 Impact Factor
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ABSTRACT: The incidence of clinically significant pulmonary embolism following total hip arthroplasty is reported in patients with venographically documented deep venous thrombosis. One hundred seventy-four patients who enrolled in a prospective evaluation of deep venous thrombosis prophylaxis underwent contrast venography 7-10 days after operation. Ten patients with proximal and 12 patients with isolated deep calf thrombosis were identified on routine venogram reading and received appropriate anticoagulant therapy, including a 6-12-week course of warfarin. There were no clinically evident embolic events and no bleeding complications in this group. A secondary blinded review of venograms several weeks later identified isolated deep calf thrombi in 13 other patients, none of whom had received warfarin after discharge. Four of the 13 patients (P < .02) subsequently presented with pulmonary embolism at a mean of 33.5 days after operation. Asymptomatic deep calf venous thrombosis following total hip arthroplasty is associated with a significant risk of developing clinically evident pulmonary embolism within the first 8 weeks after operation. Once identified, these thrombi were effectively managed with outpatient warfarin anticoagulation, and both embolic and bleeding complications were avoided. This study documents the need for more prolonged routine prophylaxis against venous thrombosis than has heretofore been the rule, extending beyond the time of discharge from the hospital. Alternatively, the authors' experience supports the use of routine screening venography following total hip arthroplasty to allow detection and selective anticoagulant treatment of deep venous thrombosis in both the thigh and calf.
The Journal of Arthroplasty 11/1993; 8(5):449-57. · 2.38 Impact Factor
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ABSTRACT: Oral anticoagulation is most frequently monitored using the prothrombin time, but an alternative approach is measurement of native, fully carboxylated, prothrombin antigen (NPA). We have correlated results of the prothrombin time and NPA with development of venous thrombosis or bleeding complications in a clinical trial of warfarin prophylaxis following total hip arthroplasty to determine the potential value of NPA measurement for monitoring oral anticoagulation.
Patients in one arm of a prospective, randomized trial received warfarin prophylactically beginning 10 to 14 days before total hip arthroplasty in a dose adjusted to prolong the international normalized ratio (INR) to 1.5 on the day of surgery and 2.5 after surgery. NPA was measured by ELISA, and the prothrombin time was measured using rabbit brain thromboplastin. Samples were tested from 97 patients, and data from 81 patients who had adequate venography were analyzed to correlate test results with occurrence of thrombosis. The prothrombin time and INR were less sensitive than NPA to the lowest intensities of anticoagulation, with the prothrombin time index increasing from 1.0 to 1.3 and the INR increasing from 1.0 to 2.0, whereas the NPA concentration decreased fourfold, from 200 to 50 micrograms/mL. There was little correlation between either the prothrombin time index or the INR and the development of thrombosis, whereas NPA concentrations were significantly higher on the day of surgery and on postoperative days 1, 3, 5, and 7 in patients who developed venous thrombosis. Higher concentrations of NPA were associated with an increased risk of venous thrombosis, but there was no relation between thrombosis and the prothrombin time index or INR. There was no significant correlation between surgical blood loss and prothrombin time index, INR, or NPA concentration. However, patients who received the largest number of transfusions on the day of surgery had significantly lower NPA concentrations than patients who required no transfusion.
These results indicate that the NPA concentration more accurately reflects the antithrombotic effect of warfarin than does prothrombin time and may be superior in monitoring prophylactic oral anticoagulation.
Circulation 09/1993; 88(2):454-60. · 14.74 Impact Factor
