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Vijay J Rasquinha

Publications and source records attributed to Vijay J Rasquinha.

12 recordsLinked to original sources
PubMed2006

Serum metal levels and bearing surfaces in total hip arthroplasty.

This study evaluates steady-state serum metal levels in patients with 4 different combinations of fixation modalities, materials, and bearing couples. Forty patients with a minimum of 5 years of follow-up and with well-functioning primary total hip arthroplasty were recruited to have serum metal levels measured. Serum chromium and cobalt levels in the metal-on-metal cohort were significantly higher (P < .05) than the other 3 cohorts. The noncemented ceramic-polyethylene cohort had significantly lower (P < .05) serum chromium levels compared to cemented and noncemented metal-polyethylene cohorts and significantly higher serum titanium levels compared to the cemented metal-polyethylene cohort which had no titanium-containing implants. Debris generated at the metal head/neck modular junction likely accounts for the significantly lower serum chromium concentration in ceramic-polyethylene bearing couples.

Aged↗
PubMed2005

Experience with an all-polyethylene total knee arthroplasty in younger, active patients with follow-up from 2 to 11 years.

There are few modern reports that document the results of all-polyethylene (all-poly) tibial components in younger, active patients. The potential benefits of this design are the elimination of backside wear and lower implant cost than modular, metal-backed components. Nonetheless, since the mid 1980s, modular, metal-backed tibial trays have dominated the total knee arthroplasty market based on finite-element analysis studies that demonstrated superior force distribution compared with conventional all-poly components. As a result, backside wear has become an emerging problem and refocused design efforts on unitized components. Our clinical experience indicates that an all-poly tibial component fixed with cement can provide excellent performance and survivorship even in younger, active patients at intermediate follow-up.

Age Factors↗
PubMed2005

Total knee arthroplasty for severe valgus deformity.

BACKGROUND: In 1985, the senior author (C.S.R.) developed a new soft-tissue release technique to balance valgus knees to avoid unacceptably high rates of late-onset instability and the need for primary constrained implants. This report describes the soft-tissue release technique and its long-term results when performed in primary total knee arthroplasty in patients with a severe valgus knee deformity. METHODS: Four hundred and ninety consecutive total knee arthroplasties were performed by one surgeon between January 1988 and December 1992. In this group, seventy-one patients (eighty-five knees) had a valgus deformity of 10 degrees . Thirty-two patients (thirty-six knees) died, and four patients (seven knees) were lost to follow-up, leaving thirty-five patients (forty-two knees) followed for a minimum of five years. These twenty-seven women and eight men had a mean age of sixty-seven years at the time of the index operation. The technique included an inside-out soft-tissue release of the posterolateral aspect of the capsule with pie-crusting of the iliotibial band and resection of the proximal part of the tibia and distal part of the femur to provide a balanced, rectangular space. Cemented, posterior stabilized implants were used in all knees. Clinical and radiographic evaluations were performed at one, five, and ten years postoperatively. RESULTS: The mean modified Knee Society clinical score improved from 30 points preoperatively to 93 points postoperatively, and the mean functional score improved from 34 to 81 points. The mean range of motion was 110 degrees both preoperatively and postoperatively. The mean coronal alignment was corrected from 15 degrees of valgus preoperatively to 5 degrees of valgus postoperatively. Three patients underwent revision surgery because of delayed infection, premature polyethylene wear, and patellar loosening in one patient each. There were no cases of delayed instability. CONCLUSIONS: The inside-out release technique to correct a fixed valgus deformity in patients undergoing primary total knee arthroplasty is reproducible and provides excellent long-term results.

Aged↗
PubMed2004

Comparison of the PFC Sigma fixed-bearing and rotating-platform total knee arthroplasty in the same patient: short-term results.

This study compares the fixed-bearing PFC Sigma Total Knee Arthroplasty to the recently introduced rotating-platform version of the same design in 26 patients. At an average follow-up time of 46 months for the fixed-bearing side and 16 months for the rotating-platform side, no significant differences were found in terms of knee preference, knee pain, range of motion, overall satisfaction, or Knee Society scores (KSSs). No revisions, subluxations, dislocations, or infections were seen. Also no radiographic evidence of component loosening, osteolysis, or malalignment was found in any knee. The results of cementing the PFC Sigma rotating-platform, posterior-stabilized total knee show excellent patient satisfaction at 1 year and comparable clinical and radiographic results to the fixed-bearing version.

Aged↗
PubMed2004

Mastering the art of cemented femoral stem fixation.

Cemented femoral stem fixation is reproducible and provides excellent early recovery of hip function in patients 60 to 80 years old. The durability of fixation has been evaluated up to 20 years with 90% survivorship. Achieving a uniform cement mantle and minimizing polyethylene wear has been shown to reduce the incidence of fixation failure. This article describes the senior author's (C.S.R.) technique for cemented total hip arthroplasty with particular emphasis on the art of cemented femoral stem fixation and his experience with 3 different cemented stem designs over 30 years. The results of using this cement technique with a modern stem design with a surface roughness of 30 to 40 microinches have produced a 95% survivorship at 10- to 20-year follow-up in patients 60 to 80 years old.

Aged↗
PubMed2004

A prospective, randomized, double-blind study of smooth versus rough stems using cement fixation: minimum 5-year follow-up.

This prospective randomized double-blind study aims to evaluate the effect of surface finish of the cemented femoral stem in primary total hip arthroplasty. Between January 1996 and May 1997, a single surgeon prospectively implanted 244 primary THAs (237 patients) using cemented femoral stems with modified third-generation cement technique in selected patients. Patients were randomized to receive the Ranawat-Burstein prosthesis (Biomet, Warsaw, IN) with 1 of 2 finishes (smooth-Ra 17 or rough-Ra 170). At a minimum 5-year follow-up, no statistical differences were found between the 2 groups. One patient with a smooth stem underwent revision of the femoral component at 2 years secondary to aseptic loosening. There was no other evidence of radiographic loosening or osteolysis. As an isolated variable, surface finish does not appear to significantly influence results at mean follow-up of 6.5 years.

Aged↗
PubMed2004

Durability of the cemented femoral stem in patients 60 to 80 years old.

The importance of surface roughness and durability of fixation of the cemented femoral stem were examined. Three cohorts of patients approximately 60 to 80 years old, had cemented total hip replacements: Charnley (1978-1983) with first-generation cement technique consisting of canal-plugging and digital packing; Omnifit (1986-1991), and Ranawat-Burstein (R-B) Interlok (1992-1994) with modified third-generation cement technique. Kaplan-Meier survivorships, using failure for all causes (best case) were 90% +/- 5.1% at 20 years for the Charnley 95.1%+/- 3.4% at 15 years for the Omnifit and 99.5% +/- 0.5% at 9 years for the R-B Interlok prosthesis. Log rank test with paired data showed no significant differences between the groups for mechanical failure as an end point. Comparisons of survivorship curves for failure from all causes showed significant differences between the Charnley compared with the Omnifit and Interlok series respectively, with no significant differences between the Omnifit and R-B Interlok series. The cemented femoral stem, with a good cement mantle and surface roughness ranging from 30 to 150 microinches, did not show any significant differences in mechanical failure. Other variables such as stem centralization and low polyethylene wear need additional evaluation in survivorship of cemented total hip replacements.

Adult↗
PubMed2004

Total knee arthroplasty for severe valgus deformity. Five to fourteen-year follow-up.

BACKGROUND: In 1985, the senior author (C.S.R.) developed a new soft-tissue release technique to balance valgus knees to avoid unacceptably high rates of late-onset instability and the need for primary constrained implants. This report describes the soft-tissue release technique and its long-term results when performed in primary total knee arthroplasty in patients with a severe valgus knee deformity. METHODS: Four hundred and ninety consecutive total knee arthroplasties were performed by one surgeon between January 1988 and December 1992. In this group, seventy-one patients (eighty-five knees) had a valgus deformity of > or =10 degrees . Thirty-two patients (thirty-six knees) died, and four patients (seven knees) were lost to follow-up, leaving thirty-five patients (forty-two knees) followed for a minimum of five years. These twenty-seven women and eight men had a mean age of sixty-seven years at the time of the index operation. The technique included an inside-out soft-tissue release of the posterolateral aspect of the capsule with pie-crusting of the iliotibial band and resection of the proximal part of the tibia and distal part of the femur to provide a balanced, rectangular space. Cemented, posterior stabilized implants were used in all knees. Clinical and radiographic evaluations were performed at one, five, and ten years postoperatively. RESULTS: The mean modified Knee Society clinical score improved from 30 points preoperatively to 93 points postoperatively, and the mean functional score improved from 34 to 81 points. The mean range of motion was 110 degrees both preoperatively and postoperatively. The mean coronal alignment was corrected from 15 degrees of valgus preoperatively to 5 degrees of valgus postoperatively. Three patients underwent revision surgery because of delayed infection, premature polyethylene wear, and patellar loosening in one patient each. There were no cases of delayed instability. CONCLUSIONS: The inside-out release technique to correct a fixed valgus deformity in patients undergoing primary total knee arthroplasty is reproducible and provides excellent long-term results. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Adult↗
PubMed2003

Fifteen-year survivorship of a collarless, cemented, normalized femoral stem in primary hybrid total hip arthroplasty with a modified third-generation cement technique.

This prospective review aimed to evaluate 15-year survivorship of the collarless, third-generation cemented, normalized, Omnifit (Osteonics, Allendale, NJ) femoral stem in hybrid total hip arthroplasty (THA). Between January 1986 and June 1990, a single surgeon prospectively implanted 250 consecutive hybrid THAs (215 patients) using a modified third-generation cement technique in selected patients. A Harris-Galante (I or II) (Zimmer, Warsaw, IN) cementless shell with modular polyethylene (4150 resin) liners gamma-sterilized in air were implanted. Kaplan-Meier survivorship of the femoral or acetabular component with mechanical failure (revision for aseptic loosening) as the end-point was 100% +/- 0% at 15 years. Wear couple exchange and bone grafting was performed in 1 case (0.4%) for progressive acetabular osteolysis. This report supports femoral component centralization and good cement mantle to ensure durability of the collarless, cemented, normalized femoral stem with a surface roughness of 30-40 microinches.

Aged↗
PubMed2002

Hydroxyapatite: catalyst or conjuror?

A prospective, randomized, intermediate-term study of 174 patients (199 hips) comparing proximally hydroxyapatite (HA)-coated and non-HA-coated surfaces of identical stem design is presented. Clinical and radiographic data from 152 patients (174 hips) confirmed comparable outcomes in both groups according to the Hospital for Special Surgery modification of the Postel--d'Aubigne Hip Rating System. The non-HA group showed significantly higher (P=.03) activity-related thigh pain, however. There were no significant radiographic differences, with all stems showing bone ongrowth. The use of HA-coated stems resulted in early recovery of function and reduced activity-related trochanteric and thigh pain. A possible explanation for the difference is most likely early superior osseointegration. HA as a biologic adjuvant should gain widespread acceptance because of rapid recovery of function and lesser trochanteric and thigh pain.

Adult↗