Biomedical subjects

R Buzzi

Publications and source records attributed to R Buzzi.

At least 19 recordsLinked to original sources

PubMed2003

Lateral collateral ligament reconstruction using a semitendinosus graft.

We evaluated 13 reconstructions of the lateral collateral ligament (LCL) of the knee associated with a reconstruction of the ACL (n=6) and PCL (n=7). In all cases the LCL was reconstructed using a semitendinosus tendon graft through a tunnel in the fibular head and fixed in anatomical insertion of LCL at lateral femoral condyle. Patients were evaluated using the IKDC form. Lateral joint opening and posterior tibial translation were studied by radiographic stress views. The follow-up average was of 60 months (38-93). In the ACL group five patient were symptoms free while one reported moderate pain after strenuous activity. The lateral stress radiographs showed lateral joint opening of 0-2 mm in five knees, and 3-5 mm in one. In the PCL group four patients were symptom free while three complained mild to moderate pain or swelling. Lateral joint opening was 0-2 mm in six knees and 3-5 in one. External rotation at 30 degrees of flexion was 10 degrees in one and between 0-5 degrees in the remainder. Eleven of 13 patients returned to their preinjury level and two returned to one level lower. These findings indicate that the LCL can be successfully reconstructed with a free ST graft at the time of ACL or PCL reconstruction.

Adolescent↗

PubMed2003

Mobile and fixed bearing total knee prosthesis functional comparison during stair climbing.

OBJECTIVE: The purpose of this investigation is to determine the functional performance of the mobile bearing total knee replacement prosthesis as compared to the fixed bearing type total knee replacement prosthesis. DESIGN: Kinematics, kinetics, and electromyography data were gained from 10 patients with mobile bearing and 10 patients with a fixed bearing posterior stabilized Insall Burstein II total knee replacement during ascending and descending stairs. A control group of 10 normal subjects, matched by sex and age, was also analysed. BACKGROUND: No significant biomechanical differences in patients with different total knee replacement designs have been reported from level-walking studies. Slightly better performance of posterior retaining with respect to cruciate sacrificing total knee replacement designs have been claimed from stair climbing studies. Only one study has been conducted regarding mobile versus fixed bearing total knee replacement assessed by gait analysis. This study did not show any biomechanical differences between the two groups. METHODS: Motion analysis was used to quantify the knee kinematics, kinetics, and electromyography (right and left longissimus dorsi, gluteus medius, rectus femoris, biceps femoris, semitendinosus, gastrocnemius and tibialis anterior muscles) during stair ascent and descent. RESULTS: The mobile bearing group demonstrated a reduced knee extensor moment during stair climbing and descending, and a reduced knee adductor moment during stair climbing. When ascending stairs, most of the mobile bearing patients show a peak knee flexion and a peak knee flexion moment at the late stance phase during the double support period. This kinematic and kinetic pattern is absent in normal subject. Both mobile bearing and fixed bearing groups showed abnormal electromyography patterns in both descending and ascending. CONCLUSIONS: During stair climbing, the mobile bearing design demonstrates a different kinematic pattern to the fixed bearing total knee replacement. Lower limb compensatory mechanisms seemed to be adopted particularly by the mobile bearing patients during ascending stairs. RELEVANCE: Total knee replacement patient with mobile bearing design can feel excessive femoro-tibial motion during daily living activities such as stair climbing and descending. Proprioceptive control of this tibio-femoral translation is needed as demonstrated by the lower limb compensatory mechanism. This data suggest that antero-posterior constraint structures (ligamentous or mechanical) are important to obtain reproducible knee kinematics.

Aged↗

PubMed2002

The Insall-Burstein II prosthesis: a 5- to 9-year follow-up study in osteoarthritic knees.

We prospectively studied 100 Insall-Burstein Posterior Stabilized II total knee arthroplasties (Zimmer Inc, Warsaw, IN) consecutively implanted in 91 patients with osteoarthritis. We reviewed 92 knees in 85 patients at a mean follow-up of 7.5 years (range, 5.3-9.5 years). According to the Knee Society score, 78 (85%) results were excellent, 11 (12%) were good, and 3 (3%) were fair or poor. The unsatisfactory results were attributed to patellofemoral pain with a low patella (2 knees) and to valgus alignment and medial laxity (1 knee). Flexion at follow-up averaged 116 degrees. Nonprogressive radiolucent lines were present around 30% of the tibial components. There was only 1 small osteolytic lesion around the tibial plateau. We observed no aspetic loosening, infection, or patella stress fracture. Survivorship analysis in the worst-case scenario showed a 90.9% success rate at 8 years.

Aged↗

PubMed2001

Patella resurfacing in total knee replacement: functional evaluation and complications.

Three different knee replacements, with three trochlear designs, were prospectively evaluated clinically and radiographically for patellar function and presence of patellar complications. They included the Insall-Burstein (IB) I and the IB-II (posterior cruciate ligament substituting) and the Meniscal Bearing Knee (MBK; posterior cruciate ligament recession). The trochlea of the IB-I was short and shallow with an anterior sharp edge of the intercondylar box (later modified to a smoother edge) and the femoral component had a prominent "shoulder." In the IB-II the trochlea was deeper to allow for soft tissue clearance. In the MBK the trochlea was more prolonged, with R and L components and the "shoulder" was less prominent. In all the cases the patella was resurfaced with an all polyethylene dome prosthesis. Knees with tibiofemoral problems were excluded. From the data of the present study the following conclusions can be drawn: (a) The most frequent problem was impingement (clunks) with the early version of the IB-I. Smoothening of the anterior edge significantly reduced the incidence of clunks to 5% in the modified IB I. (b) With the IB-II deepening the trochlea for soft tissue clearance improved the degree, not the incidence of clunks (4.5%), compared to the modified IB I. (c) With the MBK clunks were very rare and patellar function improved. (d) Throughout the three series patellar stress fractures and instability were rare and loosening or wear not evident. (e) Normal function (including stairs ascending and descending) can be expected in over 80% of category A patients. (f) Of the various radiological parameters only patella baja was correlated with symptoms in the IB prostheses. (g) We still prefer the dome design because is more tolerant and with cold flow may better conform to the trochlea increasing contact area.

Adult↗

PubMed2000

Clastogenic effects of two tyrosine kinase inhibitors, tyrphostin 23 and tyrphostin 46, on a transformed (CHO-K1) and on a primary embryonic chinese hamster cell line (CHE).

Protein tyrosine kinases (PTKs) play fundamental roles in signal transduction pathways. Many proliferative diseases are characterized by deregulation of PTK activity, therefore PTKs appear as promising targets in the design of anticancer drugs. Tyrphostins are a family of synthetic compounds which efficiently target specific PTKs without competing for ATP and thus are much less cytotoxic with respect to conventional therapeutic agents. We tested two tyrphostin derivatives, Tyrphostin 23 and Tyrphostin 46, on a transformed (CHO-K1) and on a primary embryonic Chinese hamster cell line (CHE) to determine whether these compounds had a genotoxic effect. We found that the tyrphostins increased sister chromatid exchange frequency in both cell lines, but induced chromosomal aberrations only in the transformed CHO-K1 cell line when treatment was in the S phase of the cell cycle, and not in primary CHE cells. Such a result could have important therapeutic implications: it could mean that deregulation of signal transduction pathways in cells which already have a deficit in cell cycle control could cause chromosomal aberrations.

Animals↗

PubMed1999

Femoral tunnel position in anterior cruciate ligament reconstruction using three techniques. A cadaver study.

The possibility of achieving correct deep femoral tunnel positioning during anterior cruciate ligament (ACL) reconstruction with the double incision technique (DI), the transtibial technique (TT), and the anteromedial technique (AM) was evaluated in 30 cadaver knees. A reference hole was made just deep to the insertion of the anteromedial bundle of the ACL through an anteromedial arthrotomy. In the DI technique, a Kirshner wire was inserted outside-in using a rear entry C guide. In the TT and AM techniques, the K-wire was inserted inside-out through the tibial tunnel and through the arthrotomy, respectively. The reference hole could be achieved with each technique. Using lateral radiographs, the superficial aspect of the intra-articular exit of the femoral tunnel was found to be located on average at 36%, 36%, and 34% of the width of the condyles from the posterior margin (NS). None of the holes was more anterior than 40%. In conclusion, a deep femoral tunnel positioning could be achieved with each technique. The choice of technique must be based on the surgeon's preference and clinical results.

Aged↗

PubMed1999

The Insall-Burstein total knee replacement in osteoarthritis: a 10-year minimum follow-up.

A total of 99 Insall-Burstein posterior stabilized (IBPS) knee replacements were implanted in 86 osteoarthritic patients. We reviewed 60 knees with a 10- to 15-year follow-up. Using the Knee Society score, 35 knees (58%) were excellent, 15 (25%) good, 4 (7%) fair, and 6 (10%) poor. Flexion at follow-up was 106 degrees on average. Moderate patellofemoral crepitation was present in 5 knees (9%), and 11 knee required excision of a synovial nodule proximal to the patella. Radiographic analysis showed 5 osteolytic lesions (8%) around well-fixed tibial and femoral components and minimal (1 mm) narrowing of the medial polyethylene thickness in 7 knees (12%). There were 6 (10%) failures requiring reoperation because of aseptic loosening (4 knees), deep infection (1 knee), and recurrent patellar dislocation (1 knee). Survivorship analysis using revision as the endpoint showed a cumulative success rate of 92% at 10 years. In this study, the IBPS knee has shown good long-term results with low rates of aseptic loosening and no failures attributable to polyethylene wear.

Aged↗

PubMed1999

The relationship between the intercondylar roof and the tibial plateau with the knee in extension: relevance for tibial tunnel placement in anterior cruciate ligament reconstruction.

The relationship between the intercondylar roof and the tibial plateau with the knee in full extension was studied in 100 patients with a unilateral anterior cruciate ligament (ACL) lesion. A lateral view of both knees in full extension with superimposition of the femoral condyles was obtained with the fluoroscope. We found that, in the normal knee, the roof line intersects the tibial plateau (roof-plateau intersection ratio) at 31.5% (SD +/- 5%) of its width and at 33.9% (+/- 5.4%) in the ACL deficient knee (P < .001). The difference was attributable to a subtle anterior tibial displacement in the ACL-deficient knee. Multiple regression analysis showed a direct relationship between roof-plateau intersection ratio and the angle between roof line and tibial plateau (P = .0006). A direct relationship of borderline significance (P = .06) was present with the knee recurvatum measured clinically. In conclusion, the roof-plateau intersection ratio has a wide range of variability (22% to 41%). The larger the roof-plateau angle the more posterior the roof-plateau intersection ratio.

Adolescent↗

PubMed1999

Arthroscopic meniscectomy for discoid lateral meniscus in children and adolescents: 10-year follow-up.

Seventeen adolescents underwent arthroscopic lateral meniscectomy for discoid lateral meniscus. The average age at surgery was 13.6 years (range: 5-18 years). The main preoperative symptom was pain in 16 knees and extension loss in 1 knee. At arthroscopy, 10 menisci were complete, 4 were incomplete, and 3 were Wrisberg type. Arthroscopic total meniscectomy was performed in the 3 Wrisberg types, 2 complete types, and 1 incomplete type. The remaining menisci underwent partial meniscectomy. The average follow-up was 10 years (range: 5-15 years). According to the Ikeuchi rating system, 12 knees were rated as excellent (no symptoms and full range of motion), 4 were rated as good (occasional pain), and 1 was rated as fair (patellofemoral pain in an obese patient). Radiographic evaluation showed development of minor osteophytes in the lateral compartment of 8 knees and <50% narrowing of the lateral joint space in 11 knees. No correlation was found between meniscal type, type of meniscectomy (partial or total), and clinical and radiographic results. Arthroscopic lateral meniscectomy for discoid lateral meniscus in adolescents was effective in relieving symptoms during a 10-year follow-up period. Longer follow-up is needed to ascertain the significance of the radiographic changes seen in this study.

Adolescent↗

PubMed1998

Anatomic versus non-anatomic tibial fixation in anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft.

We prospectively compared two series of 30 anterior cruciate ligament (ACL) reconstructions each where the bone-patellar tendon-bone graft was alternately fixed at the level of the tibial plateau (group A; anatomic fixation) or distal to the plateau level (group B; non-anatomic fixation). In group A, a 35-mm-long tibial tuberosity bone block was harvested. The distal 10-15 mm were resected and fixed proximally to the undersurface of the tendon to shorten it. After an average 18 months' follow-up, there were no significant differences between the two groups concerning subjective evaluation, symptoms, range of motion and objective stability. Tibial tuberosity pain was more frequent in group A (53% vs 17%, P = 0.01). Radiographic evaluation showed that tibial tunnel enlargement was less frequent in group A (23% vs 43%, P = 0.02). There was no correlation between tunnel enlargement and objective stability. In conclusion, fixation of the graft at the tibial plateau level did not improve objective stability in this study. Because of the greater technical difficulty and occurrence of tibial tuberosity pain, this technique is not recommended.

Adolescent↗

PubMed1997

Arthroscopic-assisted anterior cruciate ligament reconstruction with the central third patellar tendon. A 5-8-year follow-up.

We reviewed 89 arthroscopically assisted patellar tendon anterior cruciate ligament (ACL) reconstructions for chronic isolated injuries with an average follow-up of 7 years (range 5.4 to 8.6 years). Pain was present in 7 knees (8%). Giving-way symptoms were reported by 7 patients (8%). A KT-2000 side-to-side difference over 5 mm at 30 lbs was recorded in 12 cases (16%). The pivot shift was glide in 17 cases (19%) and clunk in 10 (11%). A 3 degrees-5 degrees extension loss compared with the normal side was present in 20 knees (22%) and 6 degrees-10 degrees in 4 knees (4%). The intra-articular exit of the femoral tunnel was misplaced in the anterior 50% of the condyles along the roof of the notch in 10% of the knees. This positioning significantly (P = 0.003) increased the frequency of graft failure (62.5%) compared with the cases with a more posterior placement (graft failure 12%). An anterior position of the intra-articular exit of the tibial tunnel (in the anterior 15% of the sagittal width of the tibia) significantly (P = 0.01) increased the frequency of extension loss > 5 degrees. Medial meniscectomy was associated with a 35% incidence of narrowing of the medial joint space, which was significantly higher compared with knees with normal menisci (9%; P = 0.04) or with medial meniscal repair (7%; P = 0.05). In conclusion this study showed satisfactory anterior stability (KT-2000 side-to-side difference up to 5 mm and pivot absent or glide) in 83% of the knees. This percentage increases to 88% in the knees with a correct posterior and proximal femoral tunnel placement. Accuracy in tunnel positioning is essential for the success of ACL surgery. Meniscal repair was effective in decreasing joint space narrowing and should be attempted when possible.

Adolescent↗

PubMed1996

The Insall-Burstein posterior stabilized total knee replacement in the valgus knee.

Sixty-seven Insall-Burstein (Zimmer Inc, Warsaw, Indiana) posteriorly stabilized total knee replacements were implanted in knees with a preoperative alignment > 10 degrees of valgus (average: 19.5 degrees). An anteromedial approach with release of the lateral ligaments of the femur was used. A lateral patellar release was necessary in 49% of cases. Fifty-one knees (76%) were reviewed with an average follow-up of 6 years. Pain at follow-up was absent or mild in all of the knees except one with aseptic loosening of the tibial and patellar components. The average flexion was 105 degrees. The results according to the Knee Society Rating System were excellent in 53%, good in 39%, fair in 6%, and poor in 2%. A patellofemoral "clunk" was present in three knees (6%), and one knee required arthroscopic debridment. The mechanical axis was within 5 degrees of neutral in 88%. A survivorship analysis was performed using failure requiring reoperation as the end point. There were four failures due to aseptic loosening, symptomatic lateral ligamentous instability, deep infection, and recurrent patellar dislocation. The patellar component had not been implanted in the knee with recurrent patellar dislocation due to severe bony erosion. The cumulative success rate was 95% at 10 years. These results indicate that release of the contracted lateral structures and implantation of a posteriorly stabilized prosthesis achieve a stable and well-aligned knee in 66 out of 67 knees. Attention must be paid to patellar tracking and realignment of the extensor mechanism.

Adult↗

PubMed1995

Results of surgical treatment of arthrofibrosis after ACL reconstruction.

We prospectively studied 31 knee arthrolyses performed for loss of motion after intra-articular anterior cruciate ligament (ACL) reconstruction. The arthrolysis was performed on average 10.6 months after the reconstruction (range 4-25). Seven knees were localized forms. They were treated with arthroscopic removal of a fibrous nodule and scar tissue anterior to the ACL, which was preserved. Twenty-four knees were global forms and treated arthroscopically (14) or in open procedure (10). Suprapatellar, medial, and lateral gutter adhesions were sectioned, and fibrous tissue was removed from the anterior compartment. A posteromedial and/or posterolateral capsulotomy was necessary in 7 knees. The ACL graft was nonfunctional and/or malpositioned in 19 knees. The results were evaluated with the IKDC form with an average follow-up of 3.5 years (range 1.5-7). Preoperatively the localized forms had an average extension loss of 11 degrees and an average flexion loss of 14 degrees compared to the opposite knee. At follow-up all the knees were satisfactory for symptoms. All except one achieved a satisfactory motion (within 5 degrees of extension loss and 15 degrees of flexion loss) and a satisfactory final result. Global forms had a greater preoperative flexion loss (average 34 degrees) and extension loss (average 17 degrees). At follow-up 58% were satisfactory for symptoms and 71% for arc of motion. However, the final result was satisfactory in only 37%. In conclusion, local forms have a good prognosis. In global forms motion may be improved by surgery, but the final result is downgraded by symptoms. Arthrolyses performed within 8 months from index operation had a better outcome.

Anterior Cruciate Ligament Injuries↗

PubMed1995

Insall-Burstein posterior-stabilized knee prosthesis in rheumatoid arthritis.

The authors reviewed 65 Insall-Burstein (Zimmer, Warsaw, IN) total condylar posterior-stabilized knee prostheses in 50 patients with rheumatoid arthritis with a follow-up period of at least 5 years (range, 5-13 years). Forty-two knees in 31 patients were evaluated using the Knee Society knee and functional rating scores. Radiographic assessment was performed using standing long radiographs (hip to ankle). Radiolucent lines were studied using fluoroscopic-centered views. Excellent or good clinical results were obtained in 95% of the cases, and the average knee score improved from 22.5 to 90 points. No cases of radiologic loosening were observed. Incomplete radiolucent lines around the tibial component were detected in only 17% and were nonprogressive. Two patients developed hematogenous late deep infection, which required removal of the prosthesis in both, followed, at a second stage, by arthrodesis in one and prosthesis reimplantation in the other. Three knees (7%) had a painful impingement of the patella. Two of these were successfully reoperated with arthroscopic debridement of the peripatellar synovial tissues. Survivorship analysis, based on endpoints such as prosthesis removal for any cause or radiologic loosening (complete radiolucent line thicker than 1 mm, tilt, or subsidence of the component), showed a cumulative success rate of 96.2% at 13 years.

Arthritis, Rheumatoid↗

PubMed1994

Arthroscopic drilling in juvenile osteochondritis dissecans of the medial femoral condyle.

Fourteen children affected by juvenile osteochondritis dissecans of the medial femoral condyle (16 knees) were treated by arthroscopic drilling of the lesion. The average age at operation was 12.8 years, and all the knees had open physes. Conservative treatment including restriction of activities had been unsuccessfully attempted in all cases for a period of > 1 year on average. At surgery each lesion was shown to have intact articular cartilage. All the lesions progressed to healing, and the patients were asymptomatic at an average of 56 months after the operation. Radiographic examination showed reconstitution of a normal or minimally flattened profile of the medial condyle. Arthroscopic drilling of the lesion in knees with juvenile osteochondritis dissecans and intact articular cartilage was effective to promote healing. The low morbidity and easy rehabilitation justify the procedure for these young patients when conservative measures fail.

Adolescent↗

PubMed1994

Surgical treatment of recurrent dislocation of the patella.

Sixty-seven patients (69 knees) with recurrent patellar dislocation underwent either a lateral release (20 knees), a proximal realignment (14 knees), a distal realignment (16 knees), or a combined realignment (19 knees) procedure. Average respective followup was 8, 8, 6, and 4 years. Patients undergoing lateral release experienced a 40% recurrence of patellar dislocation. After a realignment procedure, redislocation was uncommon (4%), but pain and swelling were reported by 12% of the patients. Significant patellofemoral crepitation was present in 35% of the realignments. The congruence angle was corrected satisfactorily in the proximal realignments, but it remained abnormal in 25% of the distal realignments. The distance from the tuberosity to the sulcus was restored to normal by transposition of the tibial tuberosity, but remained abnormal in 36% of the proximal realignments. However, it did not preclude a good clinical result. Lateral release cannot be recommended for knees with severe dysplasia of the extensor mechanism. Proximal, distal, and combined realignments yielded similar clinical results. Retensioning of the medial structures and lateral release are effective in reducing the patella within the sulcus. Although transposition of the tuberosity is appealing, clinical advantages are less evident.

Adolescent↗

PubMed1993

Patellofemoral problems after intraarticular anterior cruciate ligament reconstruction.

A series of 226 anterior cruciate ligament (ACL) reconstructions were reviewed to determine the incidence of patellofemoral (PF) problems and the associated prognostic factors. Patients were divided into four groups according to the type of injury (acute or chronic) and operation (through an arthrotomy or arthroscopic assisted). The average follow-up period was 39 months. Overall there was a 5% incidence of PF crepitus with pain and/or swelling, and a further 20% of clear PF crepitus without pain. The change from open surgery and cast to arthroscopic surgery and early motion allowed a decrease of PF problems from 40% to 21% in acute injuries, but the difference was less marked in chronic knees. A deficit greater than 10% at the one-leg hop test was present in 75% of the knees with PF crepitus and pain. The height of the patella was increased in 5% and decreased in 17% of the knees. Patients with rehabilitation difficulties had the largest decrease in patella height, whereas a patella alta was more frequent after patellar tendon reconstruction. A significant correlation was found between PF problems and female gender, positive congruence angle, preoperative PF crepitation, rehabilitation difficulties, flexion loss greater than 10 degrees, extension loss greater than 5 degrees, and variation in the height of the patella. The importance of avoiding immobilization, rehabilitation difficulties, and permanent flexion or extension loss is emphasized.

Acute Disease↗

PubMed1992

Arthroscopic anterior cruciate ligament reconstruction with patellar tendon.

Anterior cruciate ligament reconstruction using a bone-patella tendon-bone free autologous graft was performed with an arthroscopic technique in 73 patients with chronic insufficiency. Sixty-nine (94.5%) were available for personal follow-up 3-5 years after the operation. Six patients (8%) had had postoperative difficulties in regaining a complete range of motion. Symptoms of giving-way were cured in 97% of the cases, and 89% had returned to vigorous activities. Residual anterior laxity (defined as pivot shift 2+, and/or Lachman 2+, and/or KT-1000 > 5 mm at the manual maximum) was found in 13% and was more frequent in patients with an uncorrected varus laxity. Patellofemoral crepitus was present in 17% of the knees and was associated with pain and/or swelling in a further 4%; it correlated with radiographic evidence of patellofemoral incongruence (p = 0.009). Comparison of the results with those of a previous series performed by arthrotomy revealed a decreased incidence of limited range of motion, severe patellar symptoms, and changes in patellar height. Stability was the same.

Activities of Daily Living↗