Arnold T. Berman

Glomus Tumors of the Hand: Review Of The Literature And Report On Twenty-eight Cases

Twenty-eight cases of glomus tumor of the hand have been studied from various aspects including a review of the pertinent literature, clinical manifestations, treatment, and the incidence of this lesion in relation to other hand tumors and to glomus tumors occurring extramanually. These interesting and unusual lesions often are not palpable, frequently not visible, and usually not detectable on roentgen examination. Nonetheless, the diagnosis can be readily made if there is awareness of the characteristic triad of symptoms: pain, tenderness, and cold sensitivity. Meticulous complete excision, the only recommended treatment, should result in complete cure.

Factors influencing long-term results in high tibial osteotomy.

Recorded here is a comprehensive review of the current literature on high tibial osteotomy with emphasis on postponing an inevitable total knee arthroplasty (TKA). Accompanying this review is a confirmatory, retrospective study of 35 patients with 39 high tibial osteotomies with an average follow-up study of 8.5 years (range, 3.8-15.1 years). Twenty-two of the patients (57%) had good results, seven (18%) fair, and ten (25%) poor at final follow-up examination. Nine of the 35 patients required TKA at an average of 4.7 years post-osteotomy. The percentage of good results diminished with time of follow-up study, starting at two years with 87% good results and ending at 15 years with only 57% of the patients remaining in that category. Patients lost an average of 8 degrees of flexion post-osteotomy, regardless of good, fair, or poor result. Patients with favorable results were usually younger than 60 years of age, and had less than 12 degrees of angular deformity, pure unicompartmental disease, ligamentous stability, and a preoperative range of motion are of at least 90 degrees.

Thromboembolism coincident with tourniquet deflation during total knee arthroplasty

Despite prophylactic therapy, pulmonary embolism remains the leading cause of perioperative mortality in patients undergoing total knee arthroplasty (TKA). We used transoesophageal echocardiography to monitor 29 consecutive patients during TKA. Showers of substantial amounts of echogenic material, lasting for 3-15 min, were visible in the right atrium and ventricle within 10-15 s of tourniquet deflation in all patients. A 3 x 6 mm fresh thrombus was aspirated from the central circulation of one patient. Another patient, who had had a Greenfield filter placed for previous thromboembolism, showed very little echogenic material after tourniquet deflation. The composition and importance of these echogenic emboli remain uncertain.

Thermally induced bone necrosis in rabbits. Relation to implant failure in humans.

The exposure of bone to high temperatures has become quite common, especially with the increasing use of polymethylmethacrylate (PMMA) bone cement. With particular regard to total hip arthroplasty, many authors have commented on the temperature problem induced by the curing PMMA cement mass. Polymerization temperatures at the bone-cement interface have been measured and range between 40 degrees and 110 degrees, depending on the thickness of the cement line. Thermal bone damage is implicated as a significant cause of early loosening of implanted joint prostheses. The authors designed a fluid probe to deliver heated isotonic fluid directly over exposed cortical bone on a rabbits proximal tibia. Scald temperatures ranged from 45 degrees-90 degrees for a standard exposure time of one minute. Bone tissue samples taken at intervals of one, two, and three weeks postoperatively were used to establish the thermal-damage threshold for living bone and assess regeneration potential. Controls were included to observe the reaction of bone to the surgical procedure. Bone necrosis was consistently seen in histologic sections at scald temperatures greater than or equal to 70 degrees. Although an inflammatory reaction replaced by a fibrous tissue scar was seen at the site of surgically damaged periosteum, no control animals showed evidence of either bone or marrow necrosis. These results led the authors to suggest that joint replacement systems in human bone, using PMMA bone cement, be designed to limit intraoperative temperature maximums to a level less than 70 degrees. By preventing excessive bone necrosis at the bone-cement interface, early loosening and subsequent implant failure may be significantly reduced.The exposure of bone to high temperatures has become quite common, especially with the increasing use of polymethylmethacrylate (PMMA) bone cement. With particular regard to total hip arthroplasty, many authors have commented on the temperature problem induced by the curing PMMA cement mass. Polymerization temperatures at the bone-cement interface have been measured and range between 40 degrees and 110 degrees, depending on the thickness of the cement line. Thermal bone damage is implicated as a significant cause of early loosening of implanted joint prostheses. The authors designed a fluid probe to deliver heated isotonic fluid directly over exposed cortical bone on a rabbits proximal tibia. Scald temperatures ranged from 45 degrees-90 degrees for a standard exposure time of one minute. Bone tissue samples taken at intervals of one, two, and three weeks postoperatively were used to establish the thermal-damage threshold for living bone and assess regeneration potential. Controls were included to observe the reaction of bone to the surgical procedure. Bone necrosis was consistently seen in histologic sections at scald temperatures greater than or equal to 70 degrees. Although an inflammatory reaction replaced by a fibrous tissue scar was seen at the site of surgically damaged periosteum, no control animals showed evidence of either bone or marrow necrosis. These results led the authors to suggest that joint replacement systems in human bone, using PMMA bone cement, be designed to limit intraoperative temperature maximums to a level less than 70 degrees. By preventing excessive bone necrosis at the bone-cement interface, early loosening and subsequent implant failure may be significantly reduced.

Emboli Observed with Use of Transesophageal Echocardiography Immediately after Tourniquet Release during Total Knee Arthroplasty with Cement

The right atrium and the right ventricle of fifty-five patients were imaged with transesophageal echocardiography during fifty-nine total knee arthroplasties performed with cement and the use of general anesthesia. The patients ranged in age from thirty-two to eighty-three years (mean, 65.5 years). Cardiopulmonary parameters were measured with use of hemodynamic monitoring systems, such as pulse oximeters, pulmonary artery catheters, and radial artery catheters. In addition, a femoral vein catheter was inserted on the side of the operation in ten of the fifty-five patients. Showers of echogenic material traversing the right atrium, the right ventricle, and the pulmonary artery after the tourniquet was deflated were observed to various degrees in all patients and lasted three to fifteen minutes. The mean peak intensity occurred within thirty seconds (range, twenty-four to forty-five seconds) after the tourniquet was released. The mean mixed venous oxygen saturation (and standard error of the mean) decreased (from 83 ± 0.9 to 72 ± 1.5 per cent) and the mean pulmonary arterial pressure increased (from 20 ± 1.0 to 27 ± 1.0 millimeters of mercury [2.67 ± 0.13 to 3.60 ± 0.13 kilopascals]), compared with the values before the tourniquet was released, in all patients. The pulmonary vascular resistance index increased after release of the tourniquet (to a maximum of 328 ± 29 dyne·s·cm-5·m2; p = 0.00002) only in the patients who had echogenic material that was at least 0.5 centimeter in diameter. Clinical pulmonary embolism developed postoperatively in three patients; all three had had echogenic particles that were more than 0.5 centimeter in maximum diameter on imaging. Blood aspirated from one of the pulmonary artery catheters and from five of the ten femoral vein catheters demonstrated fresh venous thrombus. Histological evaluation of the aspirates failed to demonstrate fat, marrow, or particles of polymethylmethacrylate. Surgeons should consider acute pulmonary embolism as a diagnosis when evaluating a patient who has hemodynamic collapse during total knee arthroplasty performed with cement.

Echogenic emboli upon tourniquet release during total knee arthroplasty: pulmonary hemodynamic changes and embolic composition.

Echogenic venous emboli accompany tourniquet deflation during total knee arthroplasty. The associated pulmonary hemodynamic alterations and determined embolic composition were measured in 34 patients, undergoing 35 procedures. Ten patients received a femoral venous catheter on the operative side. Hemodynamic variables, heart rate and mixed venous oximetry, end-tidal CO2 and nitrogen tensions, and transesophageal echocardiograms were recorded after induction of anesthesia (baseline), after tourniquet inflation, after cementing, and for 15 min after tourniquet deflation. Echocardiograms revealed either showers of miliary echogenic material (Group S, 9 patients), or large echogenic masses superimposed on the showers (Group MS, 26 patients). In Group MS only, pulmonary vascular resistance index increased above baseline (205±6 [sem] dyne·s·cm−2) beginning 5 min after tourniquet deflation (maximum 328±29, P < 0.05). Mean pulmonary arterial pressure increased above baseline (20±1.0 mm Hg) for both Groups S and MS beginning 3 min after tourniquet deflation (27±1.0, P < 0.05). Cardiac index did not change. Five of 10 patients demonstrated fresh thrombus from the catheter in the operative limb. Echogenic emboli occurred in all patients upon tourniquet deflation during knee arthroplasty. Pulmonary vascular resistance index increased only in patients with large echogenic material. Our data suggest that these emboli represent fresh thrombus formation during tourniquet inflation. Heparin administration prior to tourniquet inflation may diminish embolic showers.

The Incidence of large venous emboli during total knee arthroplasty without pneumatic tourniquet use

Echogenic venous emboli accompany tourniquet deflation during total knee arthroplasty.Two types of echogenic emboli appear in the central circulation: small venous emboli (miliary emboli) and large venous emboli (masses of echogenic material superimposed on miliary emboli). Presumably, medullary cavity trespass releases small and large echogenic emboli. However, patients undergoing lower extremity procedures with a tourniquet have large echogenic emboli regardless of medullary cavity invasion. Avoiding tourniquet inflation may decrease the release of large venous emboli. Thirteen patients undergoing total knee arthroplasty without pneumatic tourniquet received intramedullary guides and 11 patients received tibial extramedullary guides. Recordings of hemodynamic variables, mixed venous oximetry, end-tidal CO2, and echocardiographic images were made after the induction of anesthesia and for 15 min after femoral prosthesis cementing. Mean arterial pressure did not change during the study, and mean pulmonary arterial pressure increased minimally. Large venous emboli appeared in eight patients, small venous emboli appeared in 12 patients, and no emboli appeared in four patients. Compared with previous investigations of large venous emboli during total knee arthroplasty with a pneumatic tourniquet, multiple logistic regression analysis discloses a 5.33-fold greater risk of large venous embolism accompanied the use of a tourniquet during total knee arthroplasty. Implications: One third of knee replacements performed without a tourniquet demonstrated large emboli. Reducing marrow cavity invasion did not decrease the release of large emboli. Compared with knee replacement without tourniquet, tourniquet use places patients at a 5.33-fold greater risk of having a large emboli. (Anesth Analg 1998;87:439-44)

Blood loss with total knee arthroplasty.

A substantial drop in blood volume occurs in patients being treated by total knee arthroplasty (TKA). Of 140 TKAs (108 patients) studied to analyze this blood loss, 70 required transfusion and 70 did not. The average transfusion was 2.6 units per arthroplasty. Blood loss in the nontrans-fused group was 1.8 units per arthroplasty. The overall mean blood loss was 2.2 units per TKA. Insertion of a constrained TKA resulted in a statistically significant increase in blood loss. Preop-erative diagnosis, anesthetic technique, revision arthroplasty, patellofemoral arthroplasty, and tourniquet technique did not statistically affect the blood loss. The bulk of the blood loss is collected postoperatively in the suction drainage system.

A comparison of the mechanical properties of fiberglass cast materials and their clinical relevance.

The mechanical properties of five synthetic fiberglass casting materials were evaluated and compared with the properties of plaster of Paris. Two of the tests were designed to bear clinical relevance and the third to determine intrinsic material properties. The effect of water on strength degradation was also evaluated. It was found that the synthetics as a group are far superior to plaster of Paris in all methods of testing and that, among the synthetics, KCast Tack Free, Deltalite “S”, and KCast Improved were the stronger materials. Clinically, the most important results are that the synthetics attain their relatively high strength in a much shorter time frame than does plaster of Paris, and retain 70–90% of their strength after being immersed in water and allowed to dry.

The effect of thickness and pressure on the curing of PMMA bone cement for the total hip joint replacement.

Abstract Thermal tissue damage has a strong time-temperature dependence (Lundskog, 1972). This could be a contributing factor to the loosening and/or failure of the bone-cement interface of the total hip prosthesis. An in vitro apparatus is described which simulates conditions in the acetabulum during the Charnley-Muller type low friction arthroplasty procedure, providing a direct measurement of the temperature history of the surface where the bone would be in contact. Low density polyethylene, with a thermal diffusivity of 1.58 × 10 −3 cm 2 /s was used to model the cancellous bone of the hip. The viscosity of the Surgical Simplex P bone cement, as measured by the time required for a fixed amount of penetration into the cement mass by a needle under constant load, was kept constant throughout the experimental runs. The optimal viscosity for flow of bone cement into small holes in the acetabular shell was investigated. Flow into holes the size of cancellous interstices was enhanced only when the cement was very non-viscous (at the point at which it could first be gathered up). Data from these experiments indicate that the temperature at the bone-cement interface is linearly dependent on local cement thickness and that variables such as viscosity, pressure and load, age of cement and geometry, are accounted for through their effect on the local cement thickness. The possibility of thermal necrosis resulting from the temperature-time history at the cement-bone interface was investigated. A cumulative damage effect was based on the phenomenological time-temperature plot of Henriques and Moritz. It was shown that 46% of the experimental runs exhibited a necrotic time-temperature behavior, and that this usually occurred when the local cement thickness was in excess of 5 mm.