Ricardo Dizioli Navarro

Approach towards total knee arthroplasty in Brazil: cross-sectional study

CONTEXT AND OBJECTIVE Total knee arthroplasty (TKA) has evolved particularly since the 1970s, with improvements in implants and surgical instruments, and has thus become an effective intervention for treating knee arthrosis. Many studies have presented rates of satisfactory clinical and radiological results greater than 90%, from follow-ups of over ten years. Nevertheless, despite scientific evidence showing the efficacy of TKA, the approaches taken present controversies in certain respects. The objective of this study was to evaluate how the Brazilian orthopedists deal with TKA, with investigation of the main aspects of this procedure. DESIGN AND SETTING Cross-sectional survey conducted during the 39th Brazilian Congress of Orthopedics and Traumatology, in São Paulo, Brazil, in November 2007. METHODS We applied a questionnaire to orthopedists registered at the congress. The questionnaire was randomly distributed and participation was voluntary; 858 completed questionnaires were included in the analysis. RESULTS Most of the Brazilian orthopedists were members of SBOT and worked in the southeastern region. They used imported cemented implants through an anterior access route centered on the patella, with replacement of the joint surface of the patella and preservation of the posterior cruciate ligament. They did not have experience with simultaneous bilateral TKA. Postoperatively, they used antibiotics and suction drains for 48 hours. There was no consensus regarding prophylaxis for venous thromboembolism or the frequency of the main complications. CONCLUSION The majority of Brazilian orthopedists work in the southeastern region of the country and agree about the main aspects of the approaches towards TKA.

Relação entre o ligamento patelofemoral lateral e a largura da faceta patelar lateral

Objective: The aim of this study, with cadavers, is to evaluate the relationship between the width and length of the lateral patellofemoral ligament (LPFL) and the size of the lateral patellar articular facet (LPAF). Patellofemoral instability is closely related to patellar morphology and the lateral retinacular layers. Studies evidence that the wider the lateral patellar facet and the more strained the lateral retinaculum, the greater the tendency for development of pathology in the patellofemoral joint. Methods: 20 knees were dissected in 20 cadavers. The parts were identified according to gender, age, dissected side, length and width of LPFL and width of LPAF. In order to carry out the statistical analysis we adopted the significance level of 5% (0.050) and also used Spearman’s Coefficient of Rank Correlation. Results: The LPFL presented a mean width of 16.05 millimeters (standard deviation 2.48) and 42.10 millimeters of length (standard deviation 8.84). The width of the LPAF varied from 23 to 37 millimeters (mean 28.1). It was observed that the relationship between the LPAF and LPFL widths is not statistically significant (p=0.271), whereas the relationship between the LPAF width and the LPFL length is statistically significant (p=0.009). Conclusion: The shorter the LPFL the greater the width of the LPAF.

Arthroscopic anterior cruciate ligament double-bundle reconstruction using hamstring tendon grafts-fixation with two interference screws: technical note

In this article, an original double-bundle anterior cruciate ligament reconstruction technique is described. The procedure is developed using hamstring tendon grafts while maintaining tibial osseous insertion. Two tibial tunnels are drilled and a simplified and precise outside-in double tunnel femoral drilling technique is utilized. The graft fixation is made using only two interference screws.

Ultrasonographic study of the femoropatellar joint and its attachments in normal infants from birth to 24 months of age: part I.

Eighty knees of 40 musculoskeletally normal infants whose age ranged from 0 to 24 months (average 9.65 months) were ultrasonographically analyzed. The lengths of the patella, patellar ligament – and the Insall–Salvati index, knee being flexed at 30°, were assessed. The angles of the femoral cartilaginous sulcus knee flexed at 0, 30, 60, and 90° were also defined. Patellar length varied from 1.84 to 2.02 cm (mean, 93.3 cm; standard deviation, 0.35); patellar ligament length varied from 1.67 to 1.86 (mean, 1.76 cm; standard deviation, 0.25); the Insall–Salvati index varied from 1.04 to 1.13, (mean, 1.09; standard deviation, 0.14); and femoral cartilaginous sulcus angle ranged from 148.7 to 149.3° (average, 148.9° and standard deviation, 6.20). Statistical tests showed no significant difference in the proposed measures according to sex and side (right/left). Moreover, we did not observe significant difference in the femoral cartilaginous sulcus angle with respect to the various degrees of knee flexion. Thus, we conclude that ultrasonography is useful for determining the normal values of the Insall–Salvati index and femoral cartilaginous sulcus angle in infants from 0 to 24 months. Then, we suggest standardization of this imaging procedure for the early diagnosis of deformities, which might impair the knee in infants within this range of age.

Ultrasonographic study of the femoro-patellar joint and its attachments in infants from birth to 24 months of age. Part II: children with Down syndrome.

An ultrasonographic study was carried out in 25 infants (50 knees) with Down syndrome, whose age ranged from zero to 24 months, average being 13.2 months; 13 were males and 12 were females. The ultrasonographic investigation was performed with the knee being in full extension for the transversal view and in 30° flexion for the sagittal view. The Insall–Salvati index and femoral cartilaginous sulcus angle were measured. Insall–Salvati index values ranged from 1.06 to 1.15 (average 1.10), with standard deviation of 0.16. No significant differences were observed with regard to Insall–Salvati index values in normal children. The femoral cartilaginous sulcus angle in infants with Down syndrome ranged from 152.7 to 155.8° (average 154.3) with standard deviation of 7.959. In Down syndrome we noticed significant difference as compared to the normal values. The authors suggest that ultrasonography is useful in Down syndrome for an early diagnosis of instability of the patella.

Avaliação quantitativa das forças laterais da patela: ressonância magnética estática e cinemática

OBJECTIVE: To evaluate the usefulness of combining static and kinematic magnetic resonance imaging in the evaluation of the femoropatellar joint. MATERIALS AND METHODS: Twenty healthy volunteers (40 knees) and 23 patients (43 knees) were submitted to both static and kinematic magnetic resonance imaging on a 1.5 tesla whole-body magnetic resonance scanner. The knees were positioned at 30o flexion with the quadrature knee coil at the inner end of the examination table. The patellar translation was evaluated by measurements of bisect offset, lateral patellar displacement and patellar tilt angle. The nonparametric Wilcoxon test was utilized for statistical analysis of data resulting from the static and kinematic studies in both groups. Nonparametric Mann-Whitney test was utilized in the comparison between healthy volunteers and patients. RESULTS: Statistical analysis demonstrated significant differences (p < 0.05) between static and kinematic magnetic resonance imaging for the three parameters evaluated in both groups. Among the patients the differences between static and kinematic measurements were greater than those found in the volunteers, at 30° and 20° flexion, with bisect offset and lateral patellar displacement. CONCLUSION: Static and kinematic magnetic resonance imaging, when performed in association, demonstrated that the lateral forces being exerted on the patella are higher at a knee flexion at the range between 20° and 30°, particularly in individuals symptomatic for femoropatellar instability.

Características morfológicas, histoquímicas e imunoistoquímicas dos tendões dos músculos semitendíneo e grácil: estudo comparativo entre os sexos

OBJECTIVE: To compare the morphologic, histochemical, and immunohistochemical characteristics of the tendons of the semitendinosus and the gracilis muscles to be used as autograft in anterior cruciate ligament reconstruction surgeries in men and in women. METHODS: Tendon samples of the semitendinosus and gracilis muscles of 36 patients (36 knees) were evaluated. Ages ranged from 15 to 46 years, with a mean of 29.3 years. Regarding color, 33 patients were caucasian, and three were non-caucasian. Regarding the sid, 23 knees were right knees, and 13 were left knees. Patients were divided into two groups: men (n = 20) and women (n = 16). Tendon samples were submitted to histological, histochemical, and immunohistochemical analyses. RESULTS: No statistically significant differences were seen with respect to age, race, side, inflammatory process, vascularization, and alcioanophilia between the groups under evaluation. There was increased cellularity of semitendinosus muscle tendons when compared to gracilis muscle tendons (males p = 0.03, and females p = 0.22). The authors could observe that women show a trend to greater presence of calcifications in the tendons of the semitendinosus and the gracilis muscles (p = 0.06 and p = 0.09), and to increased degeneration of the collagen fibers of the semitendinosus muscle tendons (p = 0.06). Regarding the presence of estrogen receptors in the tendons of semitendinosus and gracilis muscles, they observed an increased number of receptors in male patients. CONCLUSION: The different genders showed morphologic, histochemical, and immunohistochemical differences in the tendons of the semitendinosus between the tendons of the gracilis and semitendinosus muscles in the male gender.

DARTHROSCOPIC DOUBLE- BUNDLE RECONSTRUCTION OF ANTERIOR CRUCIATE LIGAMENT USING HAMSTRING TENDON GRAFTS - FIXATION WITH TWO INTERFERENCE SCREWS

Surgical procedures for double-bundle reconstruction of anterior cruciate ligament, which currently use semitendinous and gracilis tendon grafts, have been described in the last decade. Most of the techniques utilize twice the hardware used in single-bundle reconstructions. We report an original anterior cruciate ligament double-bundle reconstruction technique using semitendinous and gracilis tendon grafts, maintaining their tibial bone insertions with two tibial and two femoral tunnels. A simplified and precise outside-in femoral drilling technique is utilized, and the graft fixation is made utilizing only two interference screws.