ABSTRACT
BACKGROUND@#During cup implantation, vertical height of the cup center (V-HCC) should be precisely controlled to achieve sufficient bone-cup coverage (BCC). Our study aimed to investigate the acetabular bone stock and the quantitative relationship between V-HCC and BCC in Crowe types I to III hips.@*METHODS@#From November 2013 to March 2016, pelvic models of 51 patients (61 hips) with hip dysplasia were retrospectively reconstructed using a computer software. Acetabular height and doom thickness were measured on the mid-acetabular coronal cross section. V-HCC was defined as the vertical distance of cup rotational center to the interteardrop line (ITL). In the cup implantation simulation, the cup was placed at the initial preset position, with a V-HCC of 15 mm, and moved proximally by 3-mm increments. At each level, the BCC was automatically calculated by computer. Analysis of variance and Kruskal-Wallis test were used to compare the differences between groups.@*RESULTS@#There were no significant between-group differences in maximum thickness of the acetabular doom; however, peak bone stock values were obtained at heights of 41.63 ± 5.14 mm (Crowe type I), 47.58 ± 4.10 mm (Crowe type II), and 55.78 ± 3.64 mm (Crowe type III) above the ITL. At 15 mm of V-HCC, median BCC was 78% (75-83%) (Crowe type I), 74% (66-71%) (Crowe type II), and 61% (57-68%) (Crowe type III). To achieve 80% of the BCC, the median V-HCC was 16.27 (15.00-16.93) mm, 18.19 (15.01-21.53) mm, and 24.13 (21.02-28.70) mm for Crowe types I, II, and III hips, respectively.@*CONCLUSION@#During acetabular reconstruction, slightly superior placement with V-HCC <25 mm retained sufficient bone coverage in Crowe I to III hips.
ABSTRACT
<p><b>BACKGROUND</b>Accurate evaluation of the plain radiography of lower limb is critical for preoperative planning of total knee arthroplasty (TKA). We aimed to investigate the effect of femoral lateral bowing and rotation on the radiographic measurements of distal femoral condyle resection thickness (DRT) and the distal femoral resection valgus angle (FVA).</p><p><b>METHODS</b>We analyzed 246 three-dimensional femoral models generated from computed tomography images of 123 patients, acquiring projected contours in seven positions - 20° and 10° internal rotation; 0° rotation; 10°, 20°, 30°, and 40° external rotation - for each model. Medial and lateral condyle DRTs, femoral shaft lateral bowing angle (FBA), and distal FVA were determined for each position. Linear mixed effect model was used to determine the effect of degree of femur rotation on repeated measurements of DRT or FVA.</p><p><b>RESULTS</b>FBA significantly affected the FVA and DRT (Pearson's R = 0.767 and -0.408, respectively; P < 0.000). Samples were divided into three groups according to the FBA measured in neutral position: FBA <0°: DRT 3.75 ± 1.30 mm, FVA 4.53° ± 1.27°; FBA >0° but <3°: DRT 3.39 ± 1.31 mm, FVA 5.92° ± 1.31°; FBA >3°: DRT 2.22 ± 1.31 mm, FVA 7.37° ± 1.31°. From simulated 20° internal rotation to 40° external rotation in each femoral model, the average variation ranges of radiographically measured DRT, FVA, and FBA were 0.50 ± 0.28 mm, 2.93° ± 0.96°, and 10.33° ± 1.90°, respectively, with no significant differences among the FBA groups. The degree of femoral rotation significantly affected the FVA (F = 62.148, P < 0.000), whereas there was no effect on condyle resection thickness (F = 0.4705, P = 0.494).</p><p><b>CONCLUSIONS</b>Axial femoral rotation has less effect on radiographic measurements of differences in the DRT than on those of the distal FVA.</p>
ABSTRACT
<p><b>BACKGROUND</b>Accuracy of implant placement in total knee arthroplasty (TKA) is crucial. Traditional extramedullary alignment instruments are fairly effective for achieving the desired mean tibial component coronal alignment. We modified the traditional tibial plateau resection technique and evaluated its effect on alignment restoration.</p><p><b>METHODS</b>Two hundred and eighty-two primary TKAs in our hospital between January 2013 and December 2014 were enrolled in this retrospective study. Group A consisted of 128 primary TKAs performed by one senior surgeon. Preoperative measurement of the tibial resection was conducted on radiographs, and the measured thicknesses of the lateral and medial plateau resection were used to place the tibial alignment guide. Group B consisted of 154 primary TKAs performed by the other senior surgeon, using a traditional tibial plateau resection technique. In all patients, an extramedullary guide was used for tibial resection, and preoperative and postoperative full-leg standing radiographs were used to assess the hip-knee-ankle angle (HKA), femoral component alignment angle (FA), and tibial component alignment angle (TA). A deviation ≥3° was considered unsatisfactory. Data were analyzed by unpaired Student's t-test.</p><p><b>RESULTS</b>The mean postoperative HKA and TA angles were significantly different between Groups A and B (178.2 ± 3.2° vs. 177.0 ± 3.0°, t = 2.54, P = 0.01; 89.3 ± 1.8° vs. 88.3 ± 2.0°, t = 3.75, P = 0.00, respectively). The mean postoperative FA was 88.9 ± 2.5° in Group A and 88.9 ± 2.6° in Group B, and no significant difference was detected (t = 0.10, P = 0.92). There were 90 (70.3%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 38 (29.7%) outliers (>3° deviation) in Group A, whereas there were 89 (57.8%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 65 (42.2%) outliers (>3° deviation) in Group B. The severity of the preoperative alignment deformity was a strong predictor for postoperative alignment.</p><p><b>CONCLUSIONS</b>Using conventional surgical instruments, preoperative measurement of resection thickness of the tibial plateau on radiographs could improve the accuracy of conventional surgical techniques.</p>
Subject(s)
Aged , Female , Humans , Male , Arthroplasty, Replacement, Knee , Methods , Bone Malalignment , Knee Joint , General Surgery , Postoperative Period , Retrospective Studies , Tibia , General SurgeryABSTRACT
<p><b>OBJECTIVE</b>To determine the difference of post-operative mortality between ORIF (open reduction internal fixation) and hip replacement for the treatment of intertrochanteric fracture in elderly by using survival analysis.</p><p><b>METHODS</b>The clinical data of 110 patients above 60 years old who underwent surgical treatment (ORIF or hip replacement) for the intertrochanteric fracture between April 2003 and May 2013 were retrospectively analyzed. Among the patients, 83 cases were treated with ORIF (ORIF group), there were 32 males and 51 females, aged from 61.44 to 98.75 years old with an average of (78.52 ± 7.98) years old; and 27 cases were treated with hip replacement (arthroplasty group), there were 8 males and 19 females, aged from 71.82 to 96.54 years old with an average of (79.99 ± 6.11) years old. A survival analysis was performed on the clinical data by using SPSS 110 software. The survival rate of 1-year,2-year, 5-year and the mean survival time for the total patients, the mortality rate of 1-year, 2-year in each group, the survival rate of 1-year, 2-year and mean survival time and survival curve in each group were included.</p><p><b>RESULTS</b>All wounds achieved primary healing and no deaths were found in stay hospital. All patients were followed up from 1 to 125 months with an average of (46.93 ± 29.53) months. Among all 110 cases, 31 were dead and 79 survived. The survival rate of 1-year, 2-year and 5-year was (90.7 ± 2.8)%, (82.5 ± 3.9)% and (57.6 ± 6.5)%, respectively,while the ensemble mean survival time was (84.137 ± 5.902) months. The mortality rate of 1-year, 2-year in ORIF group was 7.2% and 12.0%, respectively; and in arthroplasty group, there was 14.8% and 25.9%, respectively. There was no significant difference in mortality rate of 1-year and 2-year between two groups. According to the survival analysis of the ORIF group, the survival rate of 1-year, 2-year was (92.6 ± 2.9)%, and (85.8 ± 4.3)%, respectively, and the mean survival time was (87.508 ± 6.063) months. In arthroplasty group, the survival rate of 1-year, 2-year was (85.2 ± 6.8)% and (73.9 ± 8.5)%,and the mean survival time was (67.294 ± 11.180) months. There was significant difference in mean survival time between two groups (P < 0.05).</p><p><b>CONCLUSION</b>ORIF can achieve a better postoperative survival compare with hip replacement in treating intertrochanteric fracture in elderly.</p>