Aspergillus fumigatus infection in a mega prosthetic total knee arthroplasty: salvage by staged reimplantation with 5-year follow-up.

Fungal infection after total joint arthroplasty is an extremely serious complication and a challenge to the treating physician. When a fungal infection is compounded by a massive allograft or a metallic segmental replacement of the femur or other long bone, treatment options become increasingly limited and commonly have led to arthrodesis or amputation of the infected limb. We present the first case report of a low-grade osteosarcoma treated with a segmental distal femoral allograft prosthetic composite knee arthroplasty, which was complicated by infection with Aspergillus fumigatus. This complication was treated successfully with a staged reimplantation procedure, intravenous amphotericin, and oral fluconazole suppression. At 5 years after reimplantation, the patient has had no evidence of infection, no pain, and excellent range of motion without extensor lag. The Knee Society knee score improved from 50 to 100, and the function score improved from 40 to 100 (for both scores, 100 is the maximum).

Total knee arthroplasty in an adult with congenital dislocation of the patella.

This article reports the use of total knee arthroplasty with release of the lateral retinaculum, proximal extensor mechanism realignment, and patellar resurfacing as a valid treatment option for adult patients with congenital dislocation of the patella who have absence of the femoral sulcus and associated osteoarthritis. The patient presented in this case report had improvement of his Knee Society knee score and function score from preoperative levels of 8 and 45 to 77 and 80 postoperatively.

CT-generated 3-dimensional models for complex acetabular reconstruction.

Before undergoing complex acetabular reconstruction, 10 patients who met prospectively established criteria for severe acetabular bone deficiency received plain radiographs, computed tomography (CT) scans, and CT-generated 3-dimensional pelvic models. The radiographs, CT scans, and models each were graded according to the American Academy of Orthopaedic Surgery (AAOS) classification for acetabular deficiency. The classifications for the radiographs, CT scans, and models were then compared with findings at surgery. The models predicted acetabular deformity and AAOS classification significantly better than the other imaging modalities. The models agreed with the surgical findings in 9 of 10 cases, compared with 2 of 10 for the CT scans (P = .016) and 4 of 10 for the plain radiographs (P = .063). The models closely predicted the available space for the hemispheric acetabular shells, based on the size of the last reamer used, for the 6 hips reconstructed with standard components. Four patients required custom acetabular components; in 2 of those 4, the need for custom components was not anticipated by plain radiographs or CT scans. Three-dimensional CT-generated acetabular models were found to be useful in preoperative planning of complex acetabular reconstructions.

The effects of the rotating-hinge total knee replacement on gait and stair stepping.

We studied 7 younger and 5 older patients who had rotating-hinge total knee replacements, 10 patients who had semiconstrained total knee replacements, and 8 younger and 11 older healthy control subjects to determine the effects of the rotating-hinge device on gait and stair stepping. The younger patients with the rotating-hinge device had few significant differences from the younger control subjects during gait or stair stepping. The older patients with the rotating-hinge device had several significant differences from both the older control subjects and subjects with the semiconstrained device during gait and stair stepping. Nevertheless, the proportions of older patients with the 2 devices who were able to perform the step-on activity for the highest step were the same.

Antihistamine prophylaxis permits rapid vancomycin infusion.

OBJECTIVE: To determine whether pretreatment with intravenous antihistamines attenuates the symptoms of red-man syndrome associated with rapid vancomycin administration. DESIGN: Prospective, randomized, double-blinded, placebo-controlled study of patients undergoing elective arthroplasty. SETTING: Preoperative unit in a tertiary care center. PATIENTS: Forty preoperative patients (American Society of Anesthesiologists status I-III, receiving vancomycin prophylaxis for elective prosthetic joint replacement or revision. INTERVENTIONS: Elective orthopedic patients were randomly allocated to receive intravenous antihistamines (diphenhydramine, 1 mg/kg, and cimetidine, 4 mg/kg) or placebo before rapid vancomycin infusion (1 g over 10 mins). Hemodynamic measurements, symptoms of histamine release, and plasma histamine levels were obtained in each patient during vancomycin administration. Rapid vancomycin infusion was discontinued in cases of decreases in mean blood pressure of > or =20% or intolerable itching. MEASUREMENTS AND MAIN RESULTS: Clinical symptomatology of red-man syndrome and histamine levels were assessed using Fisher's exact test or Student's t-test. Comparison of baseline and peak histamine levels for both the treated (mean +/- SD, 0.2 +/- 0.2 vs. 4.7 +/- 2.4 ng/mL; p < .0001) and placebo patients (mean +/-SD, 0.2 +/- 0.1 vs. 3.5 +/- 3.4 ng/mL; p = .0002) was statistically significant. Although there was a significant increase in plasma histamine levels during vancomycin infusion, it did not differ between the treatment groups. Only two (11%) of the treated patients developed hypotension, vs. 12 (63%) of the placebo patients (p = .002). Rash was partially attenuated. Twelve (63%) of the treated patients developed rash, compared with 19 (100%) of the placebo patients (p = .008). The rapid infusion was discontinued in two (11%) of the treated patients, compared with 11 (58%) of the placebo patients (p = .005). Four treated patients had no symptoms of histamine release. CONCLUSIONS: Pretreatment with intravenous H1 and H2 antihistamines permitted rapid vancomycin administration in 89% of treated patients. Although protection was incomplete, rash did not predict a need to stop the rapid infusion of vancomycin in our patients.

Tryptase levels are not increased during vancomycin-induced anaphylactoid reactions.

BACKGROUND: Anaphylaxis, mediated by immunoglobulin E, may be clinically indistinguishable but is mechanistically different than chemically mediated anaphylactoid reactions induced by drugs such as morphine, curare, and vancomycin. A test to distinguish anaphylactic from anaphylactoid reactions would clarify therapeutic and medicolegal issues. Tryptase levels identify anaphylactic reactions but have not been evaluated in vivo during anaphylactoid reactions. A prospective, randomized, double-blinded, placebo-controlled trial of antihistamine chemoprophylaxis for rapid vancomycin infusion was performed, and plasma tryptase was measured using a new immunoassay. Histamine release was established by measurement of plasma histamine and the ability of prophylactic H1 and H2 antagonists to prevent common histamine-associated side effects. Tryptase levels were compared with histamine levels and clinical symptoms. METHODS: Before elective arthroplasty, 40 patients received vancomycin infusion (1 g over 10 min) and pretreatment with either antihistamines (1 mg/kg diphenhydramine and 4 mg/kg cimetidine) or placebo. Changes in tryptase (at peak histamine and 10 min after vancomycin infusion), histamine levels, and histamine-mediated symptoms were assessed using Fisher's exact test, the Student's t test, or the paired t test, as appropriate. Logistic regression models were used to quantify the association of clinical symptoms with antihistamine treatment and serum levels. RESULTS: Plasma tryptase levels were unchanged (99% CI, -0.5 to 1.6) independent of increased histamine levels, antihistamine pretreatment, clinical symptoms, or all of these. Histamine levels >1 ng/ml were significantly associated with hypotension, moderate-to-severe rash, and stopped infusion. Antihistamine pretreatment significantly decreased the incidence and severity of the reactions. CONCLUSION: Plasma tryptase levels were not significantly elevated in confirmed anaphylactoid reactions, so they can be used to distinguish chemical from immunologic reactions.

Oral antihistamines reduce the side effects from rapid vancomycin infusion.

UNLABELLED: Rapid infusion of vancomycin causes histamine-mediated side effects, hypotension, and rash, known as "red man syndrome." In this prospective, randomized, double-blind, placebo-controlled study, we examined the ability of oral antihistamines to attenuate three clinical end points: rash, hypotension, and vancomycin discontinuation, and we compared these findings with those of a similar study using IV antihistamines. Patients (ASA physical status I-III) who required vancomycin prophylaxis for elective arthroplasty received either oral antihistamines (diphenhydramine < or = 1 mg/kg and cimetidine < or = 4 mg/kg, n = 20) or placebo (n = 10) 1 h before rapid vancomycin infusion (1 g over 10 min). The vancomycin infusion was discontinued if the mean arterial blood pressure decreased by > or = 20% or if itching was intolerable for the patient. Clinically significant hypotension developed in no treated patients, compared with five (50%) patients in the placebo group (P = 0.001). Rapid infusion was stopped for one treated patient (5%) and for five (50%) patients in the placebo group (P = 0.004). Incidence (P = 0.011) and severity of rash (P = 0.015) were also reduced in treated patients. Peak histamine levels were increased but were similar for patients in both groups (mean +/- SD, 1.9+/-2.5 vs 1.6+/-2.4 ng/mL; P = 0.75). Oral antihistamines were as effective as IV antihistamines. In conclusion, oral H1 and H2 antihistamine pretreatment is a practical, safe, and inexpensive option to attenuate histamine-mediated side effects associated with rapid vancomycin infusion. IMPLICATIONS: Clinicians often must administer vancomycin faster than the 1-h recommended time, which can cause "red man syndrome" (rash, itching, hypotension). Our randomized, double-blind, placebo-controlled study showed that oral H1 and H2 antihistamine pretreatment significantly reduced the histamine-related side effects of rapid vancomycin infusion.

The use of quantitative bacteriologic assessment of bone.

The purpose of this paper was to examine whether quantitative bacteriologic assessment of bone is a reliable indicator of the adequacy of debridement of draining wounds involving bone. This is a retrospective review of 31 consecutive patients treated for draining posttraumatic/ surgical wounds involving bone. Nineteen patients met the necessary criteria and were included in the study. These patients underwent radical debridement of bone and soft tissue, intraoperative assessment of the debrided wound by rapid slide quantitative bacteriologic assessment, and closure with well-vascularized tissue. Clinical assessment of vascularity and rapid slide quantitative bacteriologic assessment of cancellous bone and soft tissue were the only prerequisites used in determining the appropriateness of wound closure in this study. At the time of most recent follow-up, none of the 19 patients had recurrent wound drainage. Two patients required a second procedure to partially elevate their flaps and drain recurrent soft-tissue infections. None of the patients had recurrence of bony infection. Seventeen patients who presented initially with fractures or osteotomies all had successful bone unions. This study demonstrates that the technique of rapid slide quantitative bacteriologic assessment of cancellous bone is a useful adjunct to surgical judgment and allows one to close draining wounds (frequently with complex wound closure options) with a high level of confidence.

Bone allografts are immunogenic and may preclude subsequent organ transplants.

The authors report a case of a 41-year-old woman with diabetes and chronic renal failure in whom antihuman leukocyte antigen antibodies developed after she received a frozen bone allograft that limited her access to organ donors. The patient had a chondrosarcoma of the right distal femur. A wide resection with segmental total knee arthroplasty was followed by a revision using a composite bone allograft prosthesis. After revision, broadly reactive lymphocytotoxic antibodies developed in the patient. The patient's panel reactive antibody level rose from 28% to a peak of 70%. Panel reactive antibody expresses the percentage of a panel of human leukocyte antigen type T lymphocytes from 40 individuals (representative of all human leukocyte antigen Class I histocompatibility antigens) to which antihuman leukocyte antigen Class I lymphocytotoxic antibodies have developed in the recipient as measured by the antiglobulin crossmatch method. The specificity of the patient's primary antibody is found in 45% of donors available in Illinois since 1988 (N = 1606). Because a positive crossmatch precludes kidney and pancreas transplantation, at least 45% of cadaver organ donors were excluded from use for this patient. This is an unusual case that focuses on the potential impact of bone allografts in patients who may need subsequent organ transplantation.

Medial gastrocnemius transposition flap for the treatment of disruption of the extensor mechanism after total knee arthroplasty.

We describe a modified technique for the salvage of a total knee arthroplasty after disruption of the extensor mechanism. Between January and December 1992, seven patients had reconstruction of the extensor mechanism with use of a medial or an extended medial gastrocnemius flap. Six of the seven patients were followed for a mean of thirty-three months (range, twenty-six to forty-one months) and were evaluated both preoperatively and postoperatively with regard to the knee and functional scores of The Knee Society as well as the range of motion, extensor lag, walking status, and patellar height. The seventh patient was lost to follow-up six months postoperatively and was excluded from the analysis of the results. Preoperatively, the knee and functional scores were 16 +/- 12.3 points and 12 +/- 12.1 points (mean and standard deviation), respectively; the mean range of motion was 70 +/- 44.0 degrees; and the mean extensor lag was 53 +/- 33.4 degrees. Postoperatively, the mean knee and functional scores improved to 82 +/- 12.4 points and 51 +/- 23.0 points, respectively; the mean range of motion improved to 100 +/- 21.8 degrees; and the mean extensor lag decreased to 24 +/- 18.8 degrees. After the procedure, all patients who previously had been dependent on a walker were able to walk about the community with or without a cane, and those who had been dependent on a wheelchair were able to walk with the assistance of a walker. Patellar height was measured according to the method of Insall and Salvati for the four patients who had a patella. Preoperatively, the patellar heights were grossly abnormal; postoperatively, they more closely approached accepted normal values for three of the four patients. Reconstruction of a complicated rupture of the extensor mechanism with use of a medial gastrocnemius transposition flap after total knee arthroplasty is a reliable option for treatment.

Cementless total hip arthroplasty in patients with steroid-induced avascular necrosis of the hip. A 62-month follow-up study.

Twenty cementless porous-coated primary total hip arthroplasties (THA) were performed on 15 patients, all of whom were diagnosed with steroid-induced avascular necrosis (AVN). The average age of the patients at the time of surgery was 45 years. Minimum follow-up period for all patients was 24 months (average follow-up period: 62 months). Patients were rated using the modified Harris hip score, as well as serial radiographs. The average hip score at follow-up examination was 88, with 17 of the 20 hips having good or excellent clinical results. No revisions of the prostheses were performed. Using radiographic criteria, 12 femoral components met the criteria for bone ingrowth, seven were considered stable with fibrous fixation, and one femoral component was loose. When good initial femoral component fit was achieved, bone ingrowth reliably followed. Three acetabular components showed migration on serial radiographs. A high rate of acetabular component wear and osteolysis was noted. Avascular necrosis has been shown to adversely affect the outcome of hip arthroplasty surgery. Previous studies of patients with advanced AVN undergoing cemented THA report a high incidence of component loosening. Literature on the results of cementless THA in this patient group is sparse. The study demonstrates encouraging clinical results for cementless THA in steroid-induced AVN. Reliable femoral component fixation occurred if a good initial component fit was achieved; however, long-term acetabular loosening and wear remain serious concerns.

Diagnostic strategy for bone and soft-tissue tumors.

The diagnostic strategy to be used for a bone tumor depends on the ability of the clinician to make an accurate differential diagnosis on the basis of clinical information and plain radiographs. The clinician must be able to classify the patient as having a non-progressive or a progressive primary benign bone tumor, a primary malignant bone tumor, or a metastatic bone tumor. Only after assignment to one of these four categories can an effective diagnostic strategy ensue. If the clinical and radiographic information favors a diagnosis of malignant or aggressive benign bone tumor, the clinician should refer the patient to an experienced orthopaedic oncologist without performing additional diagnostic tests or a biopsy. If a soft-tissue mass is 5 cm in diameter or larger on physical examination, and especially if it is deep to the fascia, the patient should also be referred to an orthopaedic oncologist, without additional evaluation or biopsy, because of the relatively high probability that the mass is malignant.

Diagnostic strategy for bone and soft-tissue tumors.

The diagnostic strategy to be used for a bone tumor depends on the ability of the clinician to make an accurate differential diagnosis on the basis of clinical information and plain radiographs. The clinician must be able to classify the patient as having a non-progressive or a progressive primary benign bone tumor, a primary malignant bone tumor, or a metastatic bone tumor. Only after assignment to one of these four categories can an effective diagnostic strategy ensue. If the clinical and radiographic information favors a diagnosis of malignant or aggressive benign bone tumor, the clinician should refer the patient to an experienced orthopaedic oncologist without performing additional diagnostic tests or a biopsy. If a soft-tissue mass is five centimeters in diameter or larger on physical examination, and especially if it is deep to the fascia, the patient should also be referred to an orthopaedic oncologist, without additional evaluation or biopsy, because of the relatively high probability that the mass is malignant.

Mobile knee reconstructions after resection of malignant tumors of the distal femur.

Limb-salvage surgery involving mobile knee reconstructions for malignant tumors about the distal femur is a desirable and achievable goal. With limb salvage, the survival rate does not decrease significantly, and the resulting function is superior to when an amputation plus a prosthesis are used. Immediate and delayed morbidity is greater after limb-salvage surgery than after amputation. However, with thorough preoperative planning, use of neoadjuvant chemotherapy as indicated, and an experienced team of surgeons, limb-salvage surgery can provide a mobile knee with excellent function in the vast majority of cases for patients with malignant tumors of the distal femur.

Limb-salvage surgery in the treatment of osteosarcoma in skeletally immature individuals.

Sacrifice of major growth plates during resection and fixed-length reconstruction of a limb in a skeletally immature child with osteosarcoma may result in a significant limb-length inequality as growth progresses. A limb-length discrepancy in the humerus may cause minor cosmetic problems but does not generally result in a significant functional deficit. In the lower extremity, tumors about the knee, including the distal femur and proximal tibia, usually present the dilemma of whether limb salvage by arthrodesis, osteoarticular allograft, or endoprosthetic replacement would result in a significant limb-length inequality and whether amputation of the extremity is a preferable procedure. The techniques of rotationplasty and an expandable endoprosthesis have been successfully used for treating skeletally immature patients with osteosarcoma of the distal femur. With regard to survival and function, the results obtained with these innovative methods are favorable compared with those of a high above-knee amputation.

Skeletal reconstruction with allograft segments following bone tumor resection.

The successful treatment of malignant neoplasms of bone requires surgical removal of the primary tumor. Limb salvage as an alternative to amputation requires surgical resection of the neoplasm with a wide margin and reconstruction of the segmental defect that is created. Transplantation of an allograft bone segment, with or without articular cartilage, is one option for reconstruction. The types of defects created and the types of reconstruction using segmental allografts are classified. Specific technical details involved in allograft reconstruction are discussed.

Staging systems for musculoskeletal neoplasms.

In the treatment of musculoskeletal neoplasms, preservation of limb function and prolongation of survival have improved over the past decade. With the current emphasis on limb salvage procedures for local control of tumors, and with the addition of adjunctive therapy, the ability to classify and stage these unusual tumors is important in determining prognosis and treatment. In such classifications, a number of prognostic factors are identified and used to define stages. Three recognized staging systems exist for sarcomas of soft tissues and two for sarcomas of bone; there is one system for benign tumors of bone. The prognostic variables used in assigning stages are common to all of these systems, but the relative significance assigned to these variables differs. Documented improvement in survival and preservation of function suggests that current staging systems are significantly affecting outcome in the management of musculoskeletal tumors.