Patient preferences in knee prostheses.

A total of 344 patients underwent bilateral total knee replacement (TKR) using a different prosthesis on each side. Four knee prostheses were used: anterior and posterior cruciate-retaining (ACL-PCL), posterior cruciate-retaining (PCL), medial or lateral pivot (MLP), and posterior cruciate-substituting (PS). All patients had good or excellent results. The range of movement, relief from pain, alignment, and stability did not vary among any of the prostheses. Forty-one of 46 patients (89%) preferred the ACL-PCL to the PS knee and 27 of 35 patients (77%) the MLP knee to the PS knee. Of the patients with an ACL-PCL knee on one side and a MLP on the other, an equal number preferred each type. The MLP knee was preferred to the PCL by 34 (79%) patients. PS and PCL knees were preferred equally. Patients with bilateral TKRs preferred retention of both their cruciate ligaments or substitution with a medial or lateral pivot prosthesis.

Fracture of the greater trochanter after hip replacement.

Fracture of the femur is one of the common complications of hip replacement surgery. Five percent of femur fractures involve just the greater trochanter. This series consisted of 21 women and nine men with fractures of just the greater trochanter after total or partial hip replacement. The fracture was displaced 2.5 cm or less in 90% of patients. Only three (10%) patients had an increase in the amount of displacement more than 2 months after the fracture was recognized. The direction of displacement was always medially and superiorly toward the femoral head, rather than directly superiorly as in an ununited trochanteric osteotomy. For 18 (60%) patients, the fracture was asymptomatic. For 12 patients, the fracture was painful or there was a significant limp. In six of the 12 patients, the pain and limp improved over several months. There were no dislocations or subluxations in this series. Three patients continued to have pain or limp but thought it was not severe and declined surgical repair and experienced progressive improvement. In three patients, the pain, a limp, or both persisted at 1 year and the displacement was 2 cm or more. These three patients underwent operative repair of the trochanter. Two patients experienced improvement after repair of the trochanter. The conclusion was that fractures of the greater trochanter generally are stable and usually do not require additional treatment.

Statin therapy decreases the risk of osteonecrosis in patients receiving steroids.

Osteonecrosis is a devastating complication of systemic steroid use. Prolonged steroid use produces a hyperlipidemic state in most patients and puts them at risk for osteoporosis and osteonecrosis. The fat content within the femoral head increases, resulting in increased intracortical pressure that may lead to sinusoidal collapse and osteonecrosis. Statins are lipid-clearing agents that dramatically reduce lipid levels in blood and tissues. Statins are widely used to prevent cardiovascular disease and have been shown to reduce the adverse effects of steroids on lipid metabolism. The purpose of this study was to determine whether the use of statin drugs affects later development of osteonecrosis in patients receiving steroids. The records of 284 patients who were taking statin drugs at the time they were started on high dose steroids were examined to determine whether osteonecrosis had developed. The patients remained on statin drugs during the entire time of steroid exposure. Magnetic resonance imaging scans were used to verify the osteonecrosis unless it was visible by radiograph. After an average of 7.5 years (minimum followup, 5 years), only three patients (1%) from the group had osteonecrosis develop. This 1% incidence is much less than the 3% to 20% incidence usually reported for patients receiving high-dose steroids. Statins may offer some protection against having osteonecrosis develop when steroid treatment is necessary.

Giant-cell lesion in a sesamoid bone of the thumb.

We treated a 72-year-old woman by excision of the right thumb sesamoid which contained a giant-cell lesion. Nine years later she had normal function and no evidence of other lesions, recurrence or metastasis. We recommend that the diagnosis of giant-cell reparative granuloma and giant-cell tumour be considered when a bony mass in a sesamoid bone is discovered. Surgical excision at least in our one case was definitive treatment.

Single bone straight line graphs for the lower extremity.

Valuable information about growth and growth prediction in the lower extremity has been provided in the past by Anderson and Green, Moseley, and Menelans. Greater patient expectations and advanced techniques for lower extremity lengthening require more precise information regarding the growth characteristics of each long bone. A simple method for predicting growth is presented for the femur and tibia. Straight line graphs similar to one described previously by Moseley for the entire lower extremity have been drawn separately for the femur and tibia. Information from a contemporary population and new knowledge about growth plate activity have been included to provide more accurate predictions. By superimposing identically scaled growth remaining graphs on these single bone straight line graphs, a simple and accurate estimate is obtained for the timing and effect of epiphysiodeses or lengthening procedures.

Nonoperative treatment of widely displaced patella fractures.

Eighteen patients with displaced patellar fractures were treated nonoperatively. All of the fractures were displaced by at least 1 cm. Ambulation and knee flexion were encouraged as soon as pain permitted. Twelve of the patients were limited in their activities by medical illnesses. Six of these patients died, and the remaining patients underwent follow-up for 2 years. No patient had severe pain, and only three had acquired significant limitations in their activities from their fractures. Nine patients had either minimal or moderate activity restrictions. There were no complications from treatment. Nonoperative treatment is a reasonable option for displaced fractures of the patella, particularly in patients whose activities are limited by chronic illness. Better results, however, are possible with operative treatment.

Inferior subluxation of the humeral head after trauma or surgery.

Inferior subluxation of the humeral head can occur after shoulder trauma or surgery. One hundred consecutive patients were evaluated prospectively after shoulder surgery or injury. The radiographic incidence of inferior subluxation of the humeral head 2 weeks after rotator cuff repair was 10%. The radiographic incidence of inferior subluxation after fracture of the proximal humerus was 42%, and the incidence 2 weeks after prosthetic humeral head replacement was 60%. The immediate postoperative radiograph showed an inferior subluxation of the humeral head in 4% of patients after prosthesis insertion, but no subluxations were seen immediately after rotator cuff repair. Radiographs made immediately after fracture of the humerus showed a 16% incidence of inferior subluxation. The inferior subluxation resolved by 6 weeks in 92% of patients with humeral fractures, 96% of patients with humeral head prostheses, and all patients who had undergone rotator cuff repair. No subluxations were seen 2 years after injury or surgery. The treatment used--early active exercises and a sling when not exercising--was effective.

Substance P level in synovial fluid may predict pain relief after knee replacement.

Substance P is readily detected in the synovial fluid of the knee in which it acts as a powerful inflammatory agent in response to injury and disease. It may be an objective predictor of pain after knee replacement surgery. The level of substance P was measured in the synovial fluid in both knees of 114 patients having unilateral and in 86 patients having bilateral total knee replacement for osteoarthritis. All had severe pain in the knee to be replaced and joint destruction. Substance P was elevated in 73% of replaced knees but not in normal or asymptomatic knees. Good or excellent pain relief was achieved in 97% of patients with an elevated preoperative level of substance P and in 61% of those with a normal preoperative level (p < 0.05 compared with preoperative values).

Growth and growth prediction of the fibula.

Growth prediction data and graphs have not been available previously for the fibula. In this report, this information is wholly derived from a longitudinal radiographic study of growth in children. Teleradiographs of the tibia and fibula in 244 children (123 boys and 121 girls) were made at 6-month intervals from age 7 until skeletal maturity. Length measurements determined the growth of the fibula. The subjects were healthy well nourished middle class Americans, mostly of Northwest European descent. Growth occurring at the fibular growth plates was determined by the relationship to the tibia. The contribution of the proximal and distal growth plates to total length was determined by multiplying the percentage of growth occurring at each age by the longitudinal growth remaining. Graphs then were constructed using the logarithmic adjustment of Colin Moseley to produce a straight line graph. The proportion of growth occurring at the proximal and distal growth plates is not equal. More growth occurs at the proximal growth plate of the fibula than at the proximal growth plate of the tibia. The overall growth contribution of the proximal fibular growth plate is 61% compared with 57% for the proximal tibia. The graphs provided allow accurate prediction of fibular growth.

C-reactive protein levels determine the severity of soft-tissue injuries.

Increased serum levels of C-reactive protein (CRP), a nonspecific indicator of tissue injury, may be valuable in determining the extent of soft-tissue injury. Patients with three types of musculoskeletal injury were included in this study: anterior cruciate ligament tear (n = 11), Achilles tendon tear (n = 7), and intervertebral disc rupture (n = 18). Patients in these three groups and three control groups (n = 37) had serum CRP levels measured immediately after injury and at 48 hours, 1 week, and 2 weeks postinjury. The status of the injury in both patient groups was confirmed through clinical findings, imaging studies, or surgical findings. Mean CRP levels in all three injury groups were highest at 48 hours (anterior cruciate ligament tears [9.2 +/- 2.1 mg/dL], Achilles tendon tears [10.1 +/- 2.2 mg/dL], and acute disc rupture [4.1 +/- 1.0 mg/dL]). In all three groups, CRP levels dropped significantly (P < 0.001) after 1 week and returned to nearly normal levels by 2 weeks. All control patients had normal levels of CRP (< 1.0 mg/dL). In the absence of other causes, an elevation in CRP concentration will aid in determining the severity of acute tissue injury.

Growth and development of the distal radius and ulna.

Deformities of the wrist and forearm may result from growth disturbance of the radius and ulna. Normal growth patterns were established by measuring the distance between the distal radial and ulnar growth plates in 244 children. The subjects were healthy, well-nourished, middle-class Americans, mostly of Northwest European descent. After the age of 5 years, the distance between the distal radial and distal ulnar growth plates progressively decreased from a mean of 6 mm to a mean of zero by age 13 in girls and age 15 in boys. These measurements are helpful in determining the normal appearance of the wrist during growth and in the early detection of growth discrepancy.

Anterior cruciate-retaining total knee arthroplasty.

Fifty patients underwent bilateral total knee arthroplasty retaining both cruciate ligaments on one side and only the posterior cruciate ligament on the other. Patients were questioned about pain, instability, "feel," and ability to climb stairs. Seventy percent of patients stated that their anterior and posterior cruciate-retaining knee was their better knee overall. Ten percent stated that their posterior cruciate-only knee was better. Twenty percent could find no difference. There were no meaningful differences in inpatient care, physical therapy requirements, strength, range of motion, or component positioning. Fourteen patients handled stairs using each knee equally. Twenty-nine climbed stairs leading with the anterior and posterior cruciate-retaining knee and seven patients led with the posterior cruciate-only knee. Complaints of clunks, pops, and clicks occurred in 11 patients with posterior cruciate-only knee arthroplasties and in 4 patients retaining both anterior and posterior cruciate ligaments. Retaining the anterior cruciate ligament can provide a knee that subjectively "feels" better.

Femoral bone loss following hip replacement. A comparative study.

Fifty femoral stems of 5 different types were compared with respect to bone retention in the proximal femur at least 3 years after implantation. Dual energy x-ray absorptiometry scans were used to compare bone mineral density in the medial neck of the replaced hip with that of the other hip where surgery had not been performed. Bone mineral density declined on average of 57% with the cemented straight stem Mueller prosthesis and 34% for the uncemented Anatomic Medullary Locking prosthesis. For the cemented Harris Precoat prosthesis, the decline in bone mineral density was 43%. Two uncemented implants with horizontal platform-type collars showed an average decline in bone mineral density of 8% and 14%. Clinically, all the stems functioned well, and excellent implant insertion technique had been used. The decline in bone mineral density was evident on plain radiographs. The decrease in bone mineral density paralleled the known decrease in the medial neck strain. This study suggests that more proximal bone will be maintained by implants that load the proximal femur in as physiologic a fashion as possible.

Ketorolac prophylaxis against heterotopic ossification after hip replacement.

Three hundred three patients undergoing total hip replacement were enrolled in a prospective, randomized, double-blind clinical study of heterotopic bone formation. All the procedures were primary arthroplasties done for osteoarthritis using an anterolateral approach. Patients with spondyloarthropathy, previous surgery, or previous head or pelvic trauma were excluded. A total of 152 patients received 60 mg of ketorolac intraoperatively and 30 mg every 8 hours for 5 doses postoperatively; another 151 patients received no prophylaxis for heterotopic bone formation. Patients in each group had similar postoperative courses. No complications related to ketorolac use were seen. There was significantly less heterotopic bone formation in the ketorolac-treated group. Severe heterotopic bone formation did not develop in any treated patient, as compared with 11 untreated patients. It is concluded that ketorolac is useful as prophylaxis to prevent heterotopic bone formation. Treatment with ketorolac is completed during hospitalization; therefore, compliance is ensured. This treatment is convenient, but not necessarily more effective than other treatments.