OBJECTIVE: To measure and compare medial proximal tibial angle (MPTA) of lower limbs under different axial rotation angles(neutral position, 30° internal rotation, 30° external rotation) on the load position radiographs, and explore changes and significance of MPTA measured within and between groups of tibia at different axial rotation positions. METHODS: From January 2018 to December 2018, 40 patients with knee osteoarthritis (KOA) were selected, with a total of 80 limbs, including 12 males and 28 females, aged from 29 to 73 years old with an average of (59.6±12.7) years old. Full length radiographs of the lower limbs were taken on neutral tibia position, 30° internal rotation and 30° external rotation, respectively. MPTA was measured and the results were compared between groups and within groups. RESULTS: MPTA measured on the left lower extremity of neutral tibia, 30° internal rotation and 30° external rotation were (86.08±2.48) °, (88.62±2.94) ° and (83.47±3.10) °, respectively. MPTA measured on the right lower limb were (86.87±1.97) °, (89.02±2.39) ° and (83.80±2.77) °, respectively, and there were no significant difference in MPTA measured between rotation angle group (P>0.05). While there were statistical difference in MPTA on the same limb between groups (P<0.05). On 30° internal rotation, MPTA of left and right lower limbs increased by (2.54±1.74) ° and (2.15±1.78) ° compared with tibia neutral position. On 30° external rotation, MPTA of left and right lower limbs decreased (2.61±2.03) ° and (3.07±1.75) ° compared with tibial neutral position. CONCLUSION When a full-length X-ray film is taken on the weight-bearing position of both lower limbs, if there is axial rotation or external rotation of tibia, MPTA will increase or decrease compared with neutral position, which may cause a certain degree of deviation in clinical operation based on the accurate measurement of MPTA. However, the extent to which this bias affects the clinical operation effect remains to be verified. In addition, limited by the total number of samples and the number of measurement groups, whether there is a linear relationship between MPTA deviation and tibial axial rotation needs to be further studied.
Male ; Female ; Humans ; Adult ; Middle Aged ; Aged ; Tibia/surgery* ; Lower Extremity ; Osteoarthritis, Knee/surgery* ; Radiography ; Osteotomy/methods* ; Knee Joint/surgery* ; Retrospective Studies

BACKGROUNDDiscoid lateral meniscus was a common meniscal dysplasia and was predisposed to tear. There were some anatomical knee variants in patients with discoid lateral meniscus. The aim of this study was to analyze the relationship between anatomical knee variants and discoid lateral meniscal tears.

METHODSThere were totally 125 cases of discoid lateral meniscus enrolled in this study from February 2008 to December 2013. Eighty-seven patients who underwent arthroscopic surgery for right torn discoid lateral meniscus were enrolled in the torn group. An additional 38 patients who were incidentally identified as having intact discoid lateral menisci on magnetic resonance imaging (MRI) findings were included in the control group. All patients were evaluated for anatomical knee variants on plain radiographs, including lateral joint space distance, height of the lateral tibial spine, height of the fibular head, obliquity of the lateral tibial plateau, squaring of the lateral femoral condyle, cupping of the lateral tibial plateau, lateral femoral condylar notch, and condylar cutoff sign. The relationship between anatomical variants and meniscal tear was evaluated. These anatomical variants in cases with complete discoid meniscus were also compared with those in cases with incomplete discoid meniscus.

RESULTSThere were no significant differences between the two groups in lateral joint space distance (P = 0.528), height of the lateral tibial spine (P = 0.927), height of the fibular head (P = 0.684), obliquity of the lateral tibial plateau (P = 0.672), and the positive rates of squaring of the lateral femoral condyle (P = 0.665), cupping of the lateral tibial plateau (P = 0.239), and lateral femoral condylar notch (P = 0.624). The condylar cutoff sign was significantly different between the two groups, with the prominence ratio in the torn group being smaller than that in the control group (0.74 ± 0.11 vs. 0.81 ± 0.04, P = 0.049). With the decision value of the prominence ratio (0.78) in predicting discoid lateral meniscal tear, the sensitivity and specificity of the cutoff sign were 66% and 71%, respectively. There were no significant differences in radiographic variants between the complete and incomplete discoid lateral meniscal groups.

CONCLUSIONSThe condylar cutoff sign observed on the tunnel view of the radiograph is helpful in predicting meniscal tear in adult patients with discoid lateral meniscus. As for these patients, further MRI test is recommended.

Adolescent ; Adult ; Aged ; Arthroscopy ; Child ; Female ; Humans ; Knee Injuries ; diagnosis ; Knee Joint ; anatomy & histology ; surgery ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Radiography ; Retrospective Studies ; Young Adult

PURPOSE: To identify the accuracy of postoperative implant alignment in minimally invasive surgery total knee arthroplasty (MIS-TKA), based on the degree of varus deformity. MATERIALS AND METHODS: The research examined 627 cases of MIS-TKA from November 2005 to December 2007. The cases were categorized according to the preoperative degree of varus deformity in the knee joint in order to compare the postoperative alignment of the implant: less than 5degrees varus (Group 1, 351 cases), 5degrees to less than 10degrees varus (Group 2, 189 cases), 10degrees to less than 15degrees varus (Group 3, 59 cases), and 15degrees varus or more (Group 4, 28 cases). RESULTS: On average, the alignment of the tibial implant was 0.2+/-1.4degrees, 0.1+/-1.3degrees, 0.1+/-1.6degrees, and 0.3+/-1.7degrees varus, and the tibiofemoral alignment was 5.2+/-1.9degrees, 4.7+/-1.9degrees, 4.9+/-1.9degrees, and 5.1+/-2.0degrees valgus for Groups 1, 2, 3, and 4, respectively, in the preoperative stage, indicating no difference between the groups (p>0.05). With respect to the accuracy of the tibial implant alignment, 98.1%, 97.6%, 87.5%, and 86.7% of Groups 1, 2, 3, and 4, respectively, had 0+/-3degrees varus angulation, demonstrating a reduced level of accuracy in Groups 3 and 4 (p<0.0001). There was no difference in terms of tibiofemoral alignment, with 83.9%, 82.9%, 85.4%, and 86.7% of each group, respectively, showing 6+/-3degrees valgus angulation (p>0.05). CONCLUSION: Satisfactory component alignment was achieved in minimally invasive surgery in total knee arthroplasty, regardless of the degree of varus deformity.
Aged ; Arthroplasty, Replacement, Knee/*methods ; Bone Anteversion/complications/*radiography ; Bone Malalignment/etiology/*radiography ; Female ; Humans ; Joint Deformities, Acquired/*surgery ; Knee Joint/radiography/*surgery ; Knee Prosthesis ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures/*methods ; Osteoarthritis, Knee/complications/radiography/*surgery ; Postoperative Period ; Preoperative Period ; Range of Motion, Articular ; Tibia/surgery ; Treatment Outcome

OBJECTIVETo evaluate long-term result of Scorpio posterior-stabilized total knee arthroplasty.

METHODSThere were 160 patients (240 knees) underwent Scorpio posterior-stabilized total knee arthroplasty between December 1998 and December 2000, which were performed by the same surgeon. Patients were followed up from June 2013 to December 2013. Knee Society Scoring (KSS), Hospital for Special Surgery (HSS) patellofemoral scoring, standard weight-bearing anteroposterior and patellar tangential radiographs were assessed. Satisfaction of outcome was requested. Alignment of components and presence of radiolucent lines were assessed by the radiographic scoring system of knee society. Paired t-test was used compared to the data between preoperation and the time of last follow-up.

RESULTSNinety-five patients (141 knees) (59.4%) were followed up. Average follow-up duration was 13.3 years (range 12 to 15 years). Eight knees were revised due to periprosthetic infection (4 knees), aseptic loosening of tibial tray (3 knees) and wear-out of polyethylene insert (1 knee). Compared with preoperative ones, KSS knee score, KSS functional score and range of motion improved significantly (pre-operation: 26±16, 34±18, 87°±25°; follow-up time: 93±8, 78±27, 114°±22°) (t=45.55, 15.60, 13.03, all P<0.01). In terms of KSS knee score and HSS patellofemoral score, 106 knees were rated as excellence respectively. Ninety-five knees had satisfaction with outcome for maximum. The presences of radiolucent lines occurred around 5 femoral and 11 tibial components with range less than 2 mm. The survival rate at 10 years was 94.5% with revision for any reason as the end point.

CONCLUSIONThe long-term study indicates that Scorpio posterior-stabilized knee system shows favorable clinical and radiological results.

Arthroplasty, Replacement, Knee ; methods ; Femur ; diagnostic imaging ; Follow-Up Studies ; Humans ; Knee Joint ; surgery ; Knee Prosthesis ; Patella ; diagnostic imaging ; Polyethylene ; Radiography ; Range of Motion, Articular ; Reoperation ; Tibia ; diagnostic imaging ; Treatment Outcome

BACKGROUND: Clinical and radiologic evaluation and analyses of the surgeries using Buechel and Pappas (B-P) knee implants. METHODS: The study was conducted on 60 patients who underwent 94 total knee replacement arthroplasty with B-P knee implants from May 2009 to December 2010. The results were compared to the results of 41 patients who underwent 60 knee joint surgeries using NexGen-LPS implants from January 2008 to August 2009. RESULTS: The American Knee Society score of the B-P knee group increased from an average of 66.9 (clinical score) and 65.5 (functional score) to 93.4 and 90.3, respectively; while those for the NexGen-LPS group increased from an average of 68.8 (clinical score) and 62.4 (functional score) to 86.3 and 76, respectively. The average ranges of motion of the B-P knee group and the NexGen-LPS group were 119.1degrees and 114.8degrees, respectively, before surgery and improved to 121.0degrees and 123.0degrees at final follow-up after the surgery. The visual analogue scale scores for the B-P knee group and the NexGen-LPS group improved from 4.7 and 4.6 to 1.4 and 1.8, respectively. The flexion contracture also improved from 5.1degrees and 6.3degrees to 0.64degrees and 1.72degrees. The tibio-femoral angle for the B-P knee group and the NexGen-LPS group also improved greatly after the surgery, from varus 0.34degrees and 0.73degrees each to valgus 6.7degrees and 6.9degrees, respectively. CONCLUSIONS: The evaluation of more than 2 years of total knee replacement arthroplasty using B-P knee implants showed good results. B-P knee implants showed a relatively higher degree of satisfaction in clinical knee score and less intraoperative bone mass removal than NexGen-LPS implants.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*instrumentation ; Female ; Follow-Up Studies ; Humans ; Knee Joint/radiography/*surgery ; *Knee Prosthesis ; Male ; Middle Aged ; Osteoarthritis, Knee/radiography/*surgery

BACKGROUNDAlthough the early clinical outcomes of total knee arthroplasty (TKA) using minimally invasive surgery techniques have been widely described, data on the mid- to long-term outcomes are limited. We designed a retrospective study to compare the two most common TKA techniques - The modified quadriceps-sparing (m-QS) approach and the mini-medial parapatellar (MMP) approach - In terms of the clinical and radiographic parameters, over a minimum follow-up period of 5 years.

METHODSThe m-QS approach was used in 31 knees and the MMP approach, in 36 knees. Knees in both groups were compared for component position and alignment, knee alignment, length of the skin incision, range of motion, Visual Analog Scale score, muscle torques, Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis Index, and number of complications.

RESULTSThere were no major intergroup differences in any of the clinical and radiographic outcomes assessed at the final follow-up examination.

CONCLUSIONSOn the basis of numbers studied, the m-QS group, which requires more technique, showed equivalent results with the MMP group in the postoperative 5 years. Preservation of the extensor mechanism in the m-QS approach could not ensure any improvement in the clinical outcomes during the mid-term follow-up duration.

Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee ; adverse effects ; methods ; Female ; Follow-Up Studies ; Humans ; Knee Joint ; diagnostic imaging ; surgery ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures ; adverse effects ; methods ; Quadriceps Muscle ; diagnostic imaging ; Radiography ; Retrospective Studies

BACKGROUND: Several tendon graft and fixation methods have been introduced in medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar dislocation. The purpose of this study was to evaluate the results of MPFL reconstruction using a gracilis autograft fixation without bone tunnel in patients with recurrent patellar instability. METHODS: Nine patients (four males and five females) diagnosed with recurrent patellar instability from July 2009 to January 2013 and had MPFL reconstruction using a gracilis autograft were included. The average age of the patients was 24.6 years (range, 13 to 48 years), and the average follow-up period was 19.3 months (range, 12 to 30 months). For every patient, femoral attachment was fixed using suture anchors securing the patella by suturing the periosteum and surrounding soft tissue. Clinical evaluation included the Kujala, Lysholm, and Tegner scores; in addition, patients were examined for any complication including recurrent dislocation. The congruence angle and patella alta were assessed radiologically before and after surgery. RESULTS: The Kujala score improved from an average of 42.7 ± 8.4 before surgery to 79.6 ± 13.6 (p = 0.008) at final follow-up; the Lysholm score improved from 45.8 ± 5.7 to 82.0 ± 10.5 (p = 0.008); and the Tegner score improved from 2.8 ± 0.8 to 5.6 ± 1.5 (p = 0.007). The Insall-Salvati ratio changed from 1.16 ± 0.1 (range, 0.94 to 1.35) before surgery to 1.14 ± 0.1 (range, 0.96 to 1.29; p = 0.233) at the final follow-up without significance. The congruence angle significantly improved from 26.5°± 10.6° (range, 12° to 43°) before surgery to -4.0°± 4.3° (range, -12° to 5°; p = 0.008) at final follow-up. Subluxation was observed in one patient and hemarthrosis occurred in another patient 2 years after surgery, but these patients were asymptomatic. CONCLUSIONS: We achieved good results with a patellar fixation technique in MPFL reconstruction using a gracilis autograft employing soft tissue suturing in patients with recurrent patellar dislocation.
Adolescent ; Adult ; *Autografts ; Female ; Humans ; Knee Injuries/radiography/*surgery ; Ligaments, Articular/radiography/*surgery ; Male ; Middle Aged ; Muscle, Skeletal/surgery/transplantation ; Patella/radiography/*surgery ; Patellofemoral Joint/radiography/*surgery ; Reconstructive Surgical Procedures/adverse effects/instrumentation/*methods ; Retrospective Studies ; Thigh/surgery ; Young Adult

PURPOSE: The purpose of this study was to investigate the correlation between rotational axes of femur and tibia with the use of Linker. MATERIALS AND METHODS: This study was carried out from August 2009 to February 2010 on 54 patients (106 knees), who were diagnosed with simultaneous bilateral total knee arthroplasty. With the use of postoperative computed tomography scans, it was investigated how much the rotational angle of femoral and tibial components matched. RESULTS: The tibial component was internally rotated for the femoral component at an angle of 0.8degrees. The femoral component was externally rotated for the surgical transepicondylar axis (TEA) at an angle of 1.6 (range: from 4.8degrees of internal rotation to 7.9degrees of external rotation, SD=2.2degrees), and the tibial component was externally rotated for the surgical TEA at an average angle of 0.9 (range: from 5.1degrees of internal rotation to 8.3degrees of external rotation, SD=3.1degrees). CONCLUSION: The femoro-tibial synchronizer helped to improve the orientation and positioning of both femoral component and tibial component, and also increase the correlation of the rotational axes of the two components.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Female ; Femur/*radiography/surgery ; Humans ; Knee ; Knee Joint/*radiography/surgery ; Knee Prosthesis ; Male ; Middle Aged ; Reference Values ; Rotation ; Tibia/*radiography/surgery ; Tomography, X-Ray Computed/*methods

PURPOSE: The purpose of this study was to investigate the correlation between rotational axes of femur and tibia with the use of Linker. MATERIALS AND METHODS: This study was carried out from August 2009 to February 2010 on 54 patients (106 knees), who were diagnosed with simultaneous bilateral total knee arthroplasty. With the use of postoperative computed tomography scans, it was investigated how much the rotational angle of femoral and tibial components matched. RESULTS: The tibial component was internally rotated for the femoral component at an angle of 0.8degrees. The femoral component was externally rotated for the surgical transepicondylar axis (TEA) at an angle of 1.6 (range: from 4.8degrees of internal rotation to 7.9degrees of external rotation, SD=2.2degrees), and the tibial component was externally rotated for the surgical TEA at an average angle of 0.9 (range: from 5.1degrees of internal rotation to 8.3degrees of external rotation, SD=3.1degrees). CONCLUSION: The femoro-tibial synchronizer helped to improve the orientation and positioning of both femoral component and tibial component, and also increase the correlation of the rotational axes of the two components.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Female ; Femur/*radiography/surgery ; Humans ; Knee ; Knee Joint/*radiography/surgery ; Knee Prosthesis ; Male ; Middle Aged ; Reference Values ; Rotation ; Tibia/*radiography/surgery ; Tomography, X-Ray Computed/*methods

OBJECTIVETo determine the mechanism of pseudo-tears of the lateral meniscus caused by the transverse geniculate ligament (TL) and the miniscofemoral ligament(MFL) and to investigate a method to differentiate pseudo-tears from true tear of the lateral meniscus.

METHODSForm June 2012 to February 2014, MR examinations of 72 knees (44 left knees and 28 right knees) without tear of the lateral meniscus verified by arthroscopy were performed in the sagittal and coronal plane. There were 41 males and 31 females in the group, with an average age of 33.7 years old (ranged from 25 to 61). The MR appearance of the TL and the MFL was carefully observed.

RESULTSThere existed fatty tissue in the gap between the TL and the anterior horn of the lateral meniscus and its central tendinous attachment. On the sagittal images, the fatty tissue formed a linear high-signal cleft between the TL and the anterior horn of the lateral meniscus. This might be mistaken as an oblique tear within the anterior horn of the lateral meniscus. It was called as pseudo-tears of the anterior horn of the lateral meniscus. In sagittal plane, the MFL was identified as a circle-like or short stick-like area of low signal intensity anterior or posterior to the posterior cruciateligament. Nevertheless, a belt-shaped area of low signal intensity from the posterior horn of the lateral meniscus to lateral facet of the medial femoral condyle was identified in the coronal plane. A linear area of high signal intensity between the MFL and the lateral meniscus was found in sagittal plane, which might be mistaken as an oblique tear within the posterior horn of the lateral meniscus. It was called pseudo-tears of the posterior horn of the lateral meniscus. The occurrence rate of the TL was 34.7% (25/72). The prevaleribe of pseudo-tears of the anterior horn of the lateral meniscus was 18 cases. The shape of the anterior horn of the lateral meniscus was regular, and the course of the pseudo-tears cleft was oblique. The occurrence rate of the MFL was 73.6% (53/72), which included the anterior MFL 23.6% (17/72), the posterior MFL 70.8% (51/72) and the two ligaments coexisted 16.7% (12/72). The prevalence of pseudo-tears of the posterior horn of the lateral meniscus was 25 cases. All observed pseudo-tears had either in posteroinferiorly oblique direction (19/25) or in vertical direction (6/25).

CONCLUSIONBased on the location and direction of pseudo-tears and observation in the continuous sagittal plane and the coronal plane, pseudo-tears is easily differentiated from the true tear of the lateral meniscus

Adult ; Female ; Humans ; Knee Injuries ; diagnostic imaging ; surgery ; Knee Joint ; diagnostic imaging ; surgery ; Magnetic Resonance Imaging ; Male ; Menisci, Tibial ; diagnostic imaging ; surgery ; Middle Aged ; Radiography ; Tibial Meniscus Injuries