Treatment of major defects of bone with bulk allografts and stemmed components during total knee arthroplasty.

We reviewed the results an average of fifty months (range, twenty-four to 120 months) after the use of thirty-five allografts in thirty patients during primary or revision total knee replacement. Twenty-nine femoral-head allografts, five distal femoral allografts, and one proximal tibial allograft were used in conjunction with a long-stemmed implant to reconstruct large osseous defects. The patients were evaluated clinically, radiographically, and subjectively (with use of a questionnaire). Twenty-six (87 per cent) of the thirty patients had a good or excellent clinical result, and no revisions were necessary. As none of the patients had collapse of the graft, subsidence of the implant, or revision, we believe that the outcome of treatment with a femoral-head allograft, particularly in association with a component inserted with cement, is excellent. Four non-porous-coated components were placed without cement on structural allografts. Radiographically, three of those components subsided, but none of the three needed revision and two were associated with a good clinical result. Our current practice is to cement components in all arthroplasties involving grafting. Our findings suggest that the use of a stemmed component reduces the stress on the allograft, host bone, and fixation interface. In addition, such a component contributes to the longevity of a total knee replacement associated with a bone graft. Additional studies with long-term follow-up are necessary to confirm this outcome.

Thigh pain and total hip arthroplasty: scintigraphy with 2.5-year followup.

From January 1988 to May 1990, 60 patients underwent 68 total hip arthroplasties at the Eisenhower Army Medical Center. The authors excluded 11 patients (11 hips) in whom infection developed, who were lost to followup, or who had incomplete records, leaving 49 patients (57 hips) as the study population. The 35 uncemented and 22 cemented femoral stems were evaluated with technetium bone scans at 1 week, 6 months, 1 year, and 2.5 years after surgery. Patients with uncemented femoral stems had markedly more thigh pain and more radiopharmaceutical uptake around the stem tip at 2.5 years followup than did patients with cemented femoral stems. In addition, patients with thigh pain had more uptake around the stem tip and a higher incidence of bone hypertrophy around the stem tip than did those without thigh pain, suggesting stress transfer as a cause of thigh pain.

Fractures through cystic lesions of the greater trochanter. A cause of late pain after cementless total hip arthroplasty.

Four patients who presented with sudden onset of hip pain 7 to 11 years after successful porous-coated cementless hip arthroplasty are described. These four patients were all diagnosed to have fractures through osteolytic cysts in the greater trochanter. One patient was seen initially with a displaced fracture of the greater trochanter. Two patients were treated operatively with curettage of the cystic area and with polyethylene exchange. One of these patients underwent revision of the femoral component in addition to the polyethylene exchange. Two patients were treated nonoperatively. The fractures treated nonoperatively have healed and the patients have resumed their normal activities. This report should stimulate an awareness of fractures through cystic lesions of the greater trochanter as a late cause of hip pain after porous-coated cementless hip arthroplasty.

The diagnostic accuracy of history, physical examination, and radiographs in the evaluation of traumatic knee disorders.

We prospectively looked at the diagnostic accuracy of clinical examination of the knee in patients with arthroscopically documented knee injuries. The study included 156 patients with 156 knee injuries (72 acute and 84 chronic) who were seen during 1 year at Martin Army Hospital at Fort Benning Georgia. All patients were given a primary diagnosis based on their history, physical examination, and routine radiographs. Fifty-seven patients were also given one or more secondary diagnoses. Magnetic resonance imaging scans and arthrograms were not used in the evaluation of these patients. The primary diagnosis was correct in 83% of the knees. Of 57 secondary diagnoses given, 54% were correct and 31% were incomplete. An incorrect diagnosis was made in 14% of knees for both primary and secondary diagnoses. There were four patients with no identifiable lesion other than synovitis. With the increasing cost of medical care, the need for expensive diagnostic studies such as magnetic resonance imaging needs to be evaluated. The cost of a magnetic resonance image scan ranges between $600 to $1200 depending on the institution. The use of magnetic resonance imaging as a routine diagnostic aid in the clinical examination of the knee is unnecessary. Arthroscopic surgery of the knee should be based on the patient's history, physical examination, and radiographs.

Prophylactic cerclage: a method of preventing femur fracture in uncemented total hip arthroplasty.

The incidence of femur fracture in non-cemented hip arthroplasty has been reported to be between 4.1% and 27.8%. To quantitate the hoop stress generated during insertion of a femoral broach in total hip arthroplasty and determine the effect of cerclage with both braided cable and wire, we harvested 14 pairs of embalmed cadaver femurs. These were reamed and broached to duplicate the surgical technique of inserting a straight non-cemented femoral component. Group one consisted of eight matched cadaver femurs which were tested using a single 2.0 mm chrome-cobalt cable placed around the calcar of one femur, with the other serving as a control. Group two consisted of five matched cadaver femurs which were tested using a single 18 gauge cerclage wire in the same manner. In group one, the femurs serving as controls were found to have a mean microstrain of (1425.00 +/- 1180.19). The eight femurs tested with a 2 mm cable were determined to have a mean microstrain of (4179 +/- 2853.89). In group two, the femurs serving as controls were found to have a mean microstrain of (962.60 +/- 956.78). The five femurs in group two tested with a cerclage wire were determined to have a mean microstrain of (1112.00 +/- 975.66). Using a paired t-test, statistical significance was achieved with a confidence level of P less than or equal to .01 in group one. Prophylactic wiring of the proximal femur with 2 mm cable increases the hoop stress resistance and, therefore, should decrease the incidence of intraoperative femur fractures in uncemented total hip arthroplasty.

Arthroscintography for detection of femoral component loosening.

Arthroscintography is a simple and effective means of detecting femoral component loosening. Fourteen patients with painful total hip arthroplasties were evaluated using arthroscintography for the detection of femoral component loosening. Using this method, a sensitivity of 100% and a specificity of 75% were achieved. It is therefore recommended that arthroscintography become a routine part of the evaluation of painful total joint arthroplasties of the hip.

False-positive radionuclide arthroscintigraphy with a porous-coated total hip prosthesis.

The evaluation of a painful hip prosthesis for suspected loosening frequently requires a multi-modality approach. Radionuclide arthroscintigraphy is a valuable adjunct to contrast arthrography, demonstrating greater sensitivity than contrast arthrography in detecting loosening of the femoral component of the prosthesis. Despite its reliability in the evaluation of cemented hip prostheses, the value of arthroscintigraphy in patients with uncemented or porous-coated prostheses is undetermined. The case of a false-positive radionuclide arthroscintigram in a patient with an uncemented prosthesis is reported. The literature is briefly examined, and the potential implications regarding interpretation of arthroscintigraphy in patients with porous-coated prostheses are discussed.