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R Michael Meneghini

Publications and source records attributed to R Michael Meneghini.

18 recordsLinked to original sources
PubMed2006

Stem diameter and rotational stability in revision total hip arthroplasty: a biomechanical analysis.

BACKGROUND: Proximal femoral bone loss during revision hip arthroplasty often requires bypassing the deficient metaphyseal bone to obtain distal fixation. The purpose of this study was to determine the effect of stem diameter and length of diaphyseal contact in achieving rotational stability in revision total hip arthroplasty. METHODS: Twenty-four cadaveric femoral specimens were implanted with a fully porous-coated stem. Two different diameters were tested and the stems were implanted at multiple contact lengths without proximal bone support. Each specimen underwent torsional testing to failure and rotational micromotion was measured at the implant-bone interface. RESULTS: The larger stem diameter demonstrated a greater torsional stability for a given length of cortical contact (p <or= 0.05). Decreasing length of diaphyseal contact length was associated with less torsional stability. Torsional resistance was inconsistent at 2 cm of depth. CONCLUSION: Larger stem diameters frequently used in revisions may be associated with less diaphyseal contact length to achieve equivalent rotational stability compared to smaller diameter stems. Furthermore, a minimum of 3 cm or 4 cm of diaphyseal contact with a porous-coated stem should be achieved in proximal femoral bone deficiency and will likely be dependent on the stem diameter utilized at the time of surgery.

Journal Article↗
PubMed2006

Minimally invasive total knee arthroplasty with an optimized subvastus approach.

The minimally invasive surgery subvastus approach provides very good exposure through a small incision, preserves all 4 attachments of the quadriceps to the patella, does not require patella eversion, minimizes disruption in the suprapatellar pouch, and allows rapid and reliable closure of the knee. The patella and entire distal portion of the extensor mechanism can be retracted into the lateral gutter of the knee where they remain out of the way and allow direct visualization of both femoral condyles. When coupled with instruments designed specifically for small incision surgery, the modified subvastus approach is reliable, reproducible, and safe. Using a simple set of retractors the surgeon can perform the surgery without making any blind cuts or freehand cuts and that enhances surgical accuracy and patient safety.

Arthroplasty, Replacement, Knee↗
PubMed2006

The effect of the Insall-Salvati ratio on outcome after total knee arthroplasty.

The effect of total knee arthroplasty (TKA) on the Insall-Salvati ratio (ISR) and the effect of the ISR on the outcome of TKA have not been clearly established. A retrospective review of 1055 primary TKAs performed in 1997 to 1998 was performed. Radiographic measurements were made preoperatively and postoperatively, and the ISR was calculated. Regression analysis was performed to determine the effects of these variables on range of motion (ROM), Knee Society Score, and stair, function, and pain scores. Total knee arthroplasty resulted in a decrease in the patella tendon length, as measured by the ISR in 50% of cases. Patella infera (ISR less than 0.8) developed postoperatively in 9.8% of TKAs and was twice as likely to occur in women as men. A decrease in the ISR was associated with diminished stair and function scores (P = .0004 and 0.0081, respectively). There was no effect of the ISR upon ROM, Knee Society Score, or pain scores. Optimal outcomes occurred in patients where the ISR was not decreased after TKA, with superior stair and function scores.

Adult↗
PubMed2006

Anatomy of the extensor mechanism in reference to quadriceps-sparing TKA.

The introduction of minimally invasive surgical techniques in total joint arthroplasty has ushered in a range of new terminology that often is unclear. One such term is quadriceps-sparing total knee arthroplasty (TKA). We examined 100 knees intraoperatively in 100 patients at the time of TKA, dissected 45 entire cadaveric leg specimens, and did high-resolution 3-Tesla magnetic resonance imaging scans on five normal knees to specifically determine: (1) the distal most insertion point of the vastus medialis obliquus; (2) the angle of insertion of the vastus medialis obliquus; and (3) the length of the vastus medialis obliquus tendon. The medial anatomy of the extensor mechanism was consistent. The inferior edge of the VMO inserted at or near the midpole of the patella in each case. The tendon inserted at 50 degrees (range, 46 degrees - 52 degrees). One hundred of the 150 patients (66%) had a tendon that measured 1.2 +/- 0.1 cm, whereas 50 of 150 patients (33%) had a substantially longer tendon (2.2 +/- 0.2 cm). Any medial arthrotomy that extends more proximal than the midpole of the patella detaches a portion of the quadriceps tendon. The term "quadriceps sparing" should not be applied to any surgical approach with a capsular incision that extends more proximal than the midpole of the patella.

Adult↗
PubMed2006

Patients preferred a mini-posterior THA to a contralateral two-incision THA.

The two-incision total hip arthroplasty (THA) technique has been touted as offering substantially faster recovery than other methods of THA, but direct comparison studies in similar groups of patients have not been done. We sought to determine if there was a difference in the early functional outcome after a two-incision THA compared to a mini-posterior THA as measured by the time to reach defined milestones of daily activity. We also evaluated which procedure the patients preferred. Twenty-six patients underwent staged bilateral total hip arthroplasties with a two-incision minimally invasive THA on one hip and a mini-posterior THA on the contralateral hip. The same comprehensive anesthesia and rapid rehabilitation protocol was used after each operation. Patients were reviewed retrospectively a minimum of 6 months after the second total hip arthroplasty. There were no differences in the time to discontinue ambulatory aids, return to driving, climb stairs, return to work, or walk 1/2 mile. Sixteen of 26 patients preferred the mini-posterior total hip arthroplasty and two patients had no preference. The added surgical technical difficulty of the two-incision minimally invasive total hip arthroplasty was not rewarded with an earlier return to functional activities and more patients preferred their mini-posterior total hip arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2006

Muscle damage during MIS total hip arthroplasty: Smith-Petersen versus posterior approach.

Decreased muscle damage is a reported benefit of minimally invasive surgical (MIS) approaches in total hip arthroplasty (THA). We compared the extent and location of muscle damage during THA using the MIS anterior Smith-Petersen and MIS posterior surgical approaches. THA was performed in six human cadavers (12 hips). One hip was assigned to the Smith-Petersen approach and the contralateral hip to the posterior approach. Muscle damage was graded with a technique of visual inspection to calculate a proportion of surface area damage. Less damage occurred in the gluteus minimus muscles and minimus tendon with the Smith-Petersen approach. A mean of 8% of the minimus muscle was damaged via the Smith-Petersen approach, compared to 18% via the posterior approach. The tensor fascia latae muscle was damaged (mean of 31%), as well as direct head of the rectus femoris (mean 12%) during the Smith-Petersen approach. The piriformis or conjoined tendon was transected in 50% of the anterior approaches to mobilize the femur. The posterior approach involved intentional detachment of the piriformis and conjoined tendon and measurable damage to the abductor muscles and gluteus minimus tendon in each specimen. Clinical outcome studies and gait analysis are necessary to ascertain the functional implications of these findings.

Aged↗
PubMed2005

Implant survivorship and complication rates after total knee arthroplasty with a third-generation cemented system: 5 to 8 years followup.

UNLABELLED: We evaluated implant survivorship, reoperation rates, and complication rates of a group of patients who had total knee arthroplasty with a third-generation cemented prosthetic device using cruciate-retaining and posterior-stabilized designs at 5 to 8 years followup. Three hundred thirty-four consecutive primary total knee arthroplasties (186 cruciate retaining and 148 posterior stabilized) were done in 287 patients at our institution during a 2-year period. Kaplan Meier survivorship using revision for any reason and revision for aseptic loosening as endpoints were 95.9% and 99.5% respectively at 8 years. Nine patients (four with cruciate-retaining total knee arthroplasties, five with posterior-stabilized total knee arthroplasties; 3.1%) had reoperations for any reason. No patients had reoperation for problems related to the patellofemoral joint. Thirty-two patients (11.1%) had intraoperative or postoperative complications. There were no differences in any of the outcomes analyzed between patients who had cruciate-retaining or posterior-stabilized total knee replacements. Our results show that with appropriate patient selection and meticulous attention to surgical technique, excellent clinical and radiographic results can be achieved with a third-generation total knee arthroplasty system at intermediate followup. LEVEL OF EVIDENCE: Therapeutic study, Level III-2 (retrospective cohort study).

Aged↗
PubMed2005

Results of unicompartmental knee arthroplasty at a minimum of ten years of follow-up.

BACKGROUND: There is a renewed interest in unicompartmental knee arthroplasty. The present report describes the minimum ten-year results associated with a unicompartmental knee arthroplasty design that is in current use. METHODS: Sixty-two consecutive unicompartmental knee arthroplasties that were performed with cemented modular Miller-Galante implants in fifty-one patients were studied prospectively both clinically and radiographically. All patients had isolated unicompartmental disease without patellofemoral symptoms. No patient was lost to follow-up. Thirteen patients (thirteen knees) died after less than ten years of follow-up, leaving thirty-eight patients (forty-nine knees) with a minimum of ten years of follow-up. The average duration of follow-up was twelve years. RESULTS: The mean Hospital for Special Surgery knee score improved from 55 points preoperatively to 92 points at the time of the final follow-up. Thirty-nine knees (80%) had an excellent result, six (12%) had a good result, and four (8%) had a fair result. At the time of the final follow-up, thirty-nine knees (80%) had flexion to at least 120 degrees . Two patients (two knees) with well-fixed components underwent revision to total knee arthroplasty, at seven and eleven years, because of progression of patellofemoral arthritis. At the time of the final follow-up, no component was loose radiographically and there was no evidence of periprosthetic osteolysis. Radiographic evidence of progressive loss of joint space was observed in the opposite compartment of nine knees (18%) and in the patellofemoral space of seven knees (14%). Kaplan-Meier analysis revealed a survival rate of 98.0% +/- 2.0% at ten years and of 95.7% +/- 4.3% at thirteen years, with revision or radiographic loosening as the end point. The survival rate was 100% at thirteen years with aseptic loosening as the end point. CONCLUSIONS: After a minimum duration of follow-up of ten years, this cemented modular unicompartmental knee design was associated with excellent clinical and radiographic results. Although the ten-year survival rate was excellent, radiographic signs of progression of osteoarthritis in the other compartments continued at a slow rate. With appropriate indications and technique, this unicompartmental knee design can yield excellent results into the beginning of the second decade of use.

Aged↗
PubMed2005

Monitoring femoral component installation using vibration testing.

With emerging minimally invasive surgical techniques in total hip arthroplasty, there has been anecdotal evidence of an increase in fractures associated with the insertion of the prosthesis into the femur. The diminished visibility associated with minimally invasive surgical techniques necessitates a greater emphasis on the surgeon's tactile and auditory senses. These senses are used to ascertain the femoral component position of maximum stability and interference fit, as well as to prevent further component impaction and subsequent fracture of the femur. The work described herein attempts to identify a means to supplement the surgeon's tactile and auditory senses by using damage identification techniques normally used in civil and mechanical structures to monitor the insertion process of the prosthesis. It is hypothesized that vibration characteristics of the impact process may be used intraoperatively to determine at what position the femoral component has reached appropriate interference fit and stability in the femur. Such information may be used to prevent further impaction of the femoral component past a threshold that could result in a periprosthetic fracture. A piezoelectric accelerometer and impact hammer will be used to monitor the impact process. The acceleration time history data were analyzed by using low and high pass filters to allow frequency analysis of the time history signals. This paper will summarize features derived from the measured data that will be used to develop an insertion process termination indicator.

Arthroplasty, Replacement, Hip↗
PubMed2005

The biology of alternative bearing surfaces in total joint arthroplasty.

Periprosthetic osteolysis is currently the dominant limiting factor in joint arthroplasty longevity. Because this process is predominantly a biologic response to particulate wear debris and/or corrosion products, alternative bearing surfaces and highly cross-linked polyethylenes have been developed in an attempt to reduce the incidence of wear-induced periprosthetic osteolysis. These alternative bearing surfaces currently include ceramic-on-polyethylene, ceramic-on-ceramic, metal-on-metal, and metal or ceramic on highly cross-linked polyethylene. Although these alternative bearings diminish the generation of polyethylene debris, metallic or ceramic debris is produced. In addition, the biologic response to debris generated from alternate bearings is not fully elucidated and is related not only to particle number, but also to particle size, shape, composition, and surface area.

Arthroplasty, Replacement↗
PubMed2004

Allograft interference screw fixation in meniscus transplantation.

Allograft meniscus transplantation is indicated to restore proper knee biomechanics and prevent subsequent articular degeneration in patients with a meniscus-deficient knee. A variety of techniques for fixation of meniscal transplants exist, with some techniques using soft-tissue fixation of the meniscal horns and others using bony fixation. The authors present a technique of meniscus transplantation using a tibial slot with allograft interference screw fixation. We have had excellent early results with this technique and believe that a cortical allograft interference screw reliably maintains the anatomic position of the meniscal attachments that are critical to the biomechanics and functional outcome of meniscus transplantation.

Arthroscopy↗
PubMed2004

The progression of patellofemoral arthrosis after medial unicompartmental replacement: results at 11 to 15 years.

This study reports the 11-year to 15-year results of unicompartmental knee arthroplasty with an emphasis on failure mechanisms and progression of patellofemoral arthrosis. In a prospective study of 513 consecutive potential knee replacement candidates, 59 patients (12%) had medial unicompartmental arthroplasty of the knee. All 59 patients had isolated unicompartmental disease without clinical symptoms or radiographic evidence of patellofemoral arthritis. No patient was lost to followup. The average followup was 13 years (range, 11-15 years). The mean preoperative Hospital for Special Surgery knee score of 55 points (range, 30-79 points) improved to a mean of 90 points (range, 60-100 points) at final followup. Patellofemoral symptoms were present in 1.6% of patients at 10 years; this increased markedly to 10% of patients at 15 years (p < 0.01). Four patients (10%) had moderate or severe patellofemoral symptoms at final followup; two were revised to a primary total knee replacement at 7 and 11 years for progressive patellofemoral degeneration. No component was radiographically loose and no osteolysis was seen. The Kaplan-Meier survival with loosening or revision for any reason was 98.0% +/- 2.0% at 10 years and 95.7% +/- 4.3% at 15 years. At up to 15 years, unicompartmental knee arthroplasty yielded good clinical results; however, progressive patellofemoral arthritis was the primary mode of failure.

Aged↗
PubMed2004

Rapid rehabilitation and recovery with minimally invasive total hip arthroplasty.

To assess the potential recovery rate of a minimally invasive total hip replacement technique with minimal soft tissue disruption, an accelerated rehabilitation protocol was implemented with weightbearing as tolerated on the day of surgery. One hundred consecutive patients were enrolled in this prospective study. Ninety-seven patients (97%) met all the inpatient physical therapy goals required for discharge to home on the day of surgery; 100% of patients achieved these goals within 23 hours of surgery. Outpatient therapy was initiated in 9% of patients immediately, 62% of patients by 1 week, and all patients by 2 weeks. The mean time to discontinued use of crutches, discontinued use of narcotic pain medications, and resumed driving was 6 days postoperatively. The mean time to return to work was 8 days, discontinued use of any assistive device was 9 days, and resumption of all activities of daily living was 10 days. The mean time to walk (1/2) mile was 16 days. Furthermore, there were no readmissions, no dislocations, and no reoperations. Therefore, a rapid rehabilitation protocol is safe and fulfills the potential benefits of a rapid recovery with minimally invasive total hip arthroplasty.

Adult↗
PubMed2003

Primary hybrid total hip arthroplasty with a roughened femoral stem: integrity of the stem-cement interface.

One hundred and two consecutive cemented femoral stems were evaluated in 92 patients at an average 9-year follow-up and a minimum 5-year follow-up (range, 5-14 years). The stem used was cobalt chromium with a collar, normalization steps, and a roughened surface (Ra 40); the stem was inserted using contemporary cementing techniques. This series demonstrated a femoral component aseptic loosening rate of 2.0% and a femoral component survivorship of 97.2 +/- 2.0% at 10 years. One of 2 failed stems was revised at 95 months for failure at the cement-bone interface. The second failed stem showed failure at the cement-bone interface with incomplete debonding radiographically at 65 months. The remaining femoral components did not demonstrate any evidence of debonding at the stem-cement interface. These results compare favorably with other series of cemented femoral stems, as well as with those with a polished surface.

Aged↗
PubMedDate not supplied

Indirect arthroscopic rotator interval repair.

Repair of the capsular rotator interval has become a successful adjunct to arthroscopic procedures that address glenohumeral instability. This technical note presents a procedure that allows imbrication of the rotator interval in an indirect fashion regardless of pre-existing arthroscopic portals. A monofilament suture is passed percutaneously using a No.18-gauge spinal needle through the inferior portion of the rotator interval capsule. A soft tissue penetrator is passed through the anterior superior portal to retrieve the suture through the superior portion of the rotator interval capsule. A braided suture is then shuttled in the standard fashion. An arthroscopic knot pusher is placed on the inferior limb of the suture and drives this limb below the deltoid and anterior to the capsule to join the second limb for extracapsular fixation. The technique also provides for direct arthroscopic visualization of the repair and does not necessitate entry into the subacromial space. This is a reproducible procedure that allows efficient repair of the rotator interval.

Arthroscopy↗