We report the case of a polyethylene tibial post fracture in a 72-year-old woman 14 months after a Scorpio posterior-stabilized (PS) total knee arthroplasty. The polyethylene wear was found around the fracture site of the post, especially over the anterior aspect of the post base. The failure mechanism of the post fracture in the present case was anterior impingement with excessive wear over the base of the anterior aspect of the tibial post, which became a stress-riser of post and cam articulation. This is the first report of a polyethylene tibial post fracture of a Scorpio PS prosthesis.
Aged ; *Arthroplasty, Replacement, Knee ; Female ; Humans ; Knee Joint/radiography ; Knee Prosthesis/*adverse effects ; Osteoarthritis, Knee/surgery ; *Polyethylenes ; *Prosthesis Failure ; Reoperation

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

BACKGROUND: This study evaluated the preoperative distractive stress radiographs in order to quantify and predict the extent of medial release according to the degree of varus deformity in primary total knee arthroplasty. METHODS: We evaluated 120 varus, osteoarthritic knee joints (75 patients). The association of the angle on the distractive stress radiograph with extent of medial release was analyzed. The extent of medial release was classified into the following 4 groups according to the stage: release of the deep medial collateral ligament (group 1), release of the posterior oblique ligament and/or semimembranous tendon (group 2), release of the posterior capsule (group 3) and release of the superficial medial collateral ligament (group 4). RESULTS: The mean femorotibial angle on the preoperative distractive stress radiograph was valgus 2.4degrees (group 1), valgus 0.8degrees (group 2), varus 2.1degrees (group 3) and varus 2.7degrees (group 4). The extent of medial release increased with increasing degree of varus deformity seen on the preoperative distractive stress radiograph. CONCLUSIONS: The preoperative distractive stress radiograph was useful for predicting the extent of medial release when performing primary total knee arthroplaty.
Aged ; *Arthroplasty, Replacement, Knee/methods ; Female ; Humans ; Joint Deformities, Acquired/etiology/radiography ; Knee Joint/*radiography ; Ligaments, Articular/radiography ; Male ; Medial Collateral Ligament, Knee/*surgery ; Middle Aged ; Osteoarthritis, Knee/complications/radiography/*surgery

BACKGROUND: We hypothesized that a number of clinical and radiologic parameters could influence the reducibility of varus deformity in total knee arthroplasty. The aim of this study was to identify the factors correlated with reducibility of varus deformity and predict more accurately the amount of medial soft tissue release required in varus deformity total knee arthroplasty. METHODS: One hundred forty-three knees with preoperative varus alignment and medial osteoarthritis were included in this retrospective study. The total knee arthroplasties were performed using a navigation system (OrthoPilot) by single surgeon. To assess varus deformity, the authors measured preoperative mechanical axis angles and valgus stress angles. Mechanical tibial angles, mechanical femoral angles, femoral osteophyte sizes, and tibial osteophyte sizes were measured. The Ahlback grading scale was applied for radiologic parameters, and clinical parameters (age, body mass index, sex, duration of pain, and preoperative range of motion) were documented. Correlations between these factors and preoperative valgus stress angle were analyzed. RESULTS: A negative correlation was found between preoperative mechanical axis angle and preoperative valgus stress angle (p < 0.01, r = -0.38), and a positive correlation was found between the preoperative mechanical tibial angle and preoperative valgus stress angle (p = 0.01, r = 0.19). CONCLUSIONS: The present study shows that preoperative varus deformity and proximal tibial vara (measured by preoperative mechanical axis angle and mechanical tibial angle, respectively) are correlated with reducibility of varus deformity (measured by preoperative valgus stress angle), and clinical parameters (age, range of motion, duration of pain and body mass index) and other radiologic parameters (osteophyte size, severity of osteoarthritis and angulation of distal femoral joint surface) were not significantly correlated with reducibility of varus deformity.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Bone Malalignment/radiography/*surgery ; Female ; Humans ; Knee Joint/radiography/*surgery ; Male ; Middle Aged ; Osteoarthritis, Knee/radiography/*surgery ; Retrospective Studies ; Stereotaxic Techniques ; Surgery, Computer-Assisted

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

BACKGROUNDIsolated patellofemoral osteoarthritis is not uncommon. Surgical treatment of isolated patellofemoral arthritis remains controversial and poses a challenging treatment dilemma. The present study aimed to evaluate the short-term results of patellofemoral arthroplasty for patients with isolated patellofemoral osteoarthritis.

METHODSWe analyzed 11 patellofemoral arthroplasties performed from March 2006 to September 2009 in 11 patients with isolated patellofemoral arthritis. The patients comprised 2 males and 9 females with an average age of 53.7 years (range, 46 - 74 years). Standard weightbearing radiographs were taken in the anteroposterior, lateral, and 45° axial views. The knee pain and functional status were evaluated by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scales and American Knee Society (AKS) scores. For comparison, 23 total knee arthroplasties in 23 patients with primary tibiofemoral osteoarthritis were matched according to age, gender, bilaterality and body mass index. The duration of follow-up was 23.7 months (range, 12 - 47 months).

RESULTSThe majority of the 11 patients experienced improvement in their patellofemoral symptoms after patellofemoral arthroplasty. The WOMAC scores improved considerably by 7.4 points with respect to pain and by 5.2 points with respect to function. The AKS scores also improved considerably by 23.9 points with respect to pain and 44.3 points with respect to function. Although the clinical outcomes after patellofemoral arthroplasty were not better than those after total knee arthroplasty, patellofemoral arthroplasty exhibited advantages in the shorter operation time, lower blood loss and increased postoperative range of motion. At the latest follow-up, there was no clinical or radiographic evidence of patellofemoral maltracking, loosening or wear.

CONCLUSIONSOn the basis of our experience in this relatively small series of patients with a short-term follow-up, patellofemoral arthroplasty is an effective treatment alternative to total knee arthroplasty in isolated patellofemoral arthritis. MRI and arthroscopy may contribute to define those patients with isolated patellofemoral degeneration.

Aged ; Arthroplasty, Replacement, Knee ; methods ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; diagnostic imaging ; surgery ; Patellofemoral Pain Syndrome ; diagnostic imaging ; surgery ; Radiography ; Treatment Outcome

BACKGROUND: This study examined the results of open wedge high tibial osteotomy with using an Aescula open wedge plate and an allogenic bone graft as a surgical technique for the patients who suffer from osteoarthritis of the knee with a genu varum deformity. METHODS: From March 2007 to August 2007, 33 patients (37 cases) with osteoarthritis of the knee and a genu varum deformity underwent a high tibial osteotomy with using an Aescula open wedge plate and an allogenic bone graft. The patients were followed up for more than 1 year. Before and after surgery, the correction angle of the genu varum was measured by the lower extremity scannogram and the posterior tibial slope, the joint space distance and the time to bone union were evaluated. The functional factors were evaluated using the Knee Society Score. RESULTS: The average knee score and function score improved from 52.19 +/- 11.82 to 92.49 +/- 5.10 and 52.84 +/- 6.23 to 89.05 +/- 5.53, respectively (p < 0.001). According to the lower extremity scannogram, the mean preoperative varus angle was -1.86 +/- 2.76degrees, and the average correction angle at the last follow-up was 10.93 +/- 2.50degrees (p < 0.001). The tibial posterior slope before surgery and at the last follow-up were 8.20 +/- 1.80degrees and 8.04 +/- 1.30degrees, respectively (p = 0.437). The joint space distance increased from 4.05 +/- 1.30 mm to 4.83 +/- 1.33 mm (p < 0.001). The average time to complete bone union was 12.69 +/- 1.5 weeks. CONCLUSIONS: An open wedge high tibial osteotomy using an Aescula open wedge plate and an allogeneic bone graft to treat osteoarthritis of the knee with a genu varum deformity showed good results for the precision of the correction angle, the time to bone union and the functional improvement.
Adult ; Arthroscopy ; *Bone Plates ; *Bone Transplantation ; Female ; Humans ; Joint Deformities, Acquired/diagnosis/etiology/radiography/*surgery ; Knee Joint ; Male ; Middle Aged ; Orthopedic Procedures/*methods ; Osteoarthritis, Knee/complications/diagnosis/radiography/*surgery ; Osteotomy/*methods ; Tibia/radiography/*surgery ; Transplantation, Homologous

BACKGROUND: We report intra- and postoperative complications of unicompartmental knee arthroplasty (UKA). METHODS: This study was conducted on 246 cases of UKA which were performed for degenerative osteoarthritis confined to the medial compartment, from May 2002 to May 2010, for which follow-up periods longer than one year were available. Complications were divided into intra- and postoperative complications. Pre- and postoperative clinical scores, the range of motion, and radiologic findings were analyzed. RESULTS: Complications developed in a total of 24 cases (9.8%, 24/246). Among them, 6 cases had intraoperative complications while 18 had postoperative complications. Among the 6 intraoperative complications, one fracture of the medial tibial condyle, two fractures of the intercondylar eminence, one rupture of the medial collateral ligament, one widening of the peg hole leading to femoral component malposition and late failure, and one total knee arthroplasty (TKA) conversion of a large bony defect of tibial avascular necrosis were observed. Among the 18 postoperative complications, four cases of aseptic loosening of the femoral component, one soft tissue impingement due to malalignment, nine cases of polyethylene bearing dislocation, one case of suprapatellar bursitis, one periprosthetic fracture, one TKA conversion due to medial component overhanging, and one TKA conversion due to pain of unexplained cause were observed. CONCLUSIONS: The mid-term clinical outcomes of UKA were excellent in our study. However, the incidence of complications was very high (9.8%). To prevent intra- and postoperative complications, proper selection of the patients and accurate surgical techniques are required.
Aged ; Arthroplasty, Replacement, Knee/*adverse effects/methods ; Female ; Humans ; Intraoperative Complications ; Male ; Middle Aged ; Osteoarthritis, Knee/radiography/*surgery ; Postoperative Complications ; Retrospective Studies

OBJECTIVETo study the rotation of femoral component and tibial component with CT and evaluate the relationship between patellofemoral complications and rotational alignment of the components.

METHODSThirty patients with isolated patellofemoral complications after total knee arthroplasty were compared with 20 patients with well functioning total knee replacements free of patellofemoral complications. The epicondylar axis and tibial tubercle were used as references on CT scans to quantify the rotational alignment of the femoral and tibial components.

RESULTSPatients with patellofemoral complications had excessive combined (tibial plus femoral) internal component rotation, which was directly proportional to the severity of the patellofemoral complications. Mild combined internal rotation (1 degree-4 degrees) was correlated with patellar and lateral tracking tilting, moderate rotation (3 degrees-8 degrees) with patellar subluxation, and severe rotation (7 degrees-17 degrees) with early patellar dislocation or late patellar prosthesis failure. The control group had combined external rotation of 10 degrees-0 degree.

CONCLUSIONSThe direct correlation of combined internal component rotation to the severity of the patellofemoral complication suggests that internal component rotation may be the predominant cause of patellofemoral complications in patients with normal axis alignment. CT scans can be used intraoperatively and postoperatively to determine whether the rotational malalignment is present to require revision of one or both components.

Adult ; Aged ; Arthroplasty, Replacement, Knee ; adverse effects ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; diagnostic imaging ; physiopathology ; surgery ; Postoperative Complications ; etiology ; physiopathology ; Prosthesis Failure ; Radiography ; Rotation

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