Fixation of patella fractures with braided polyester suture: a biomechanical study.

We tested the quality of fixation of displaced transverse patella fractures using braided polyester suture to investigate the suitability of this material as an alternative to stainless steel wire for fixation of these fractures. Osteotomies were created to simulate fractures of the patella in ten cadaveric knee specimens and were sequentially fixed using two techniques: the modified tension-band technique and the longitudinal anterior band (Lotke) technique. Each technique was implemented using either 1.25-mm stainless steel wire or 7-metric braided polyester suture (No. 5 Ethibond). The quality of fixation for each technique was tested by measuring the fracture gap during three simulated extensions of the knee against gravity on a materials testing machine. All techniques behaved comparably under the loading conditions used. In the four groups, there was no fixation failure (fracture gap > 3 mm) nor any significant difference between the mean maximum fracture gaps. The quality of fixation for braided polyester suture was comparable to that of stainless steel wire for such fractures, providing sufficient stability to withstand loads likely to be encountered during postoperative rehabilitation. Our results support the use of braided polyester suture as an alternative to stainless steel wire for fixation of displaced patella fractures.

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.

Relative rates of fracture of the hip in the United States. Geographic, sex, and age variations.

We studied the Medicare data from 1984 through 1987 for 687,850 fractures of the hip that had occurred in the United States. Our purpose was to determine the geographic, sex-specific, and age-interval variations in the relative risk of fracture of the hip in elderly white individuals. The rates of cervical, trochanteric, and subtrochanteric fracture, and the over-all rate of fracture at any of the three levels, increased with age, were greater for women than for men, and were higher in the Southern part of the country. However, there were regional, sex, and age variations. The ratio of cervical to trochanteric fractures was significantly higher in the East South Central region and lower in the Middle Atlantic and New England regions (p < 0.05). These were the same areas with the highest and lowest over-all rates, respectively, of fracture of the hip. The ratio of cervical to trochanteric fractures decreased from 1.52 in women who were sixty-five to sixty-nine years old to 0.81 in women who were at least eighty-five years old, but it stayed at approximately 1.00 for the corresponding age-groups of men. The ratio of fracture of the hip in women to fracture of the hip in men varied depending on the level of the fracture.

The medial gastrocnemius muscle flap in the treatment of wound complications following total knee arthroplasty.

There is greater potential for wound healing complication in rheumatoids, diabetics, and other patients with peripheral vascular disease. Local wound care in areas of avascularity and skin necrosis has poor results, especially if an ulcer is greater than 2 cm in diameter. Gastrocnemius muscle flap coverage of persistent wounds and areas of skin necrosis following total knee arthroplasty should be considered early in the course of such a complication.

Minimum 4-year follow-up of the PCA total knee arthroplasty in rheumatoid patients.

One hundred twenty-one consecutive nonrandomized primary total knee arthroplasties in 94 patients were performed between 1980 and 1984 using the Porous-Coated Anatomic prosthesis in patients with a diagnosis of severe rheumatoid arthritis. Of the 94 patients, 81 patients were able to be followed for more than 4 years, with the remaining 13 dying from unrelated causes prior to the 48-month follow-up. Of those arthroplasties with 48-month follow-up, 55 were uncemented and 26 were cemented. An 81% good to excellent result was seen for the cemented group and a 91% good to excellent result for the uncemented group. The postoperative arc of motion for the cemented group was 94 degrees, with the postoperative arc of motion in the uncemented group being 102 degrees. In evaluation of component interfaces, there were almost no lucencies seen among the femoral group, with no component failures in either group. Thirty-six percent of the uncemented group developed nonprogressive radiolucent lines along the tibial tray; 97% of these radiolucencies were less than 1 mm. Complications in the cemented group included a revision of one patellar and one tibial component for component loosening. In the uncemented group, complications included one case of deep sepsis following an intra-articular injection, loosening of two patellar components requiring revision, and loosening of two tibial components requiring revision.

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.

Total hip arthroplasty for protrusio acetabuli: a 3- to 9-year follow up of the Heywood technique.

Thirty-five total joint arthroplasties (34 patients) were performed in patients who had protrusio acetabuli. Twenty-nine percent of the patients had acetabular protrusio of grade I, while 71% had grade II and grade III protrusio. The mean follow up was 4 years (range: 3 to 9). Cemented acetabular components were used in 11 hips; 24 hips received an uncemented porous coated acetabular component. The patient evaluations included preoperative and postoperative Harris Hip Ratings and standard radiographs. In all cases, the medial wall defect was reconstructed with the solid autogenous femoral head as described by Heywood. The mean preoperative Harris Hip Rating was 45 (range: 30 to 60 points), and the postoperative mean was 85 (range: 70 to 100 points). Radiographically, the preoperative protrusio measured a mean of 8.8 mm (range: 6 to 18 mm), and the mean postoperative placement of the femoral head was 10 mm lateral to Kohler's line (range: 6 to 13 mm). There were no acetabular component failures and no acetabular bone graft resorptions. All autogenous grafts were incorporated to the host radiographically by 1 year post-surgery. This study corroborates previous work which suggests that medial-placed bone grafting is not resorbed and consolidates with the host bone. We find this technique extremely useful in dealing with this technical problem.

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.

Treatment of proximal femur fractures associated with total hip arthroplasty.

The authors reviewed seven cases of proximal femur fractures with ipsilateral total hip arthroplasty between April 1985 and July 1987. All patients had ORIF with Odgen plates and Parham bands. Early mobilization of the patients avoided prolonged bedrest with its inherent morbidity. The morbidity of a revision of the total hip arthroplasty was also avoided. There were no problems with healing of the fractures sites and no evidence of devascularization related to Parham band utilization. All seven type A fractures went to clinical and radiographic union by 4 months and all seven were asymptomatic. The authors recommend the use of Ogden plates and Parham bands for type A fractures. Their clinical data suggest that this method is an effective treatment modality that produces a decrease in morbidity with satisfactory results.