scholarly journals Ex VivoEquine Medial Tibial Plateau Contact Pressure With an Intact Medial Femoral Condyle, With a Medial Femoral Condylar Defect, and After Placement of a Transcondylar Screw Through the Condylar Defect

2014 ◽  
Vol 44 (3) ◽  
pp. 289-296 ◽  
Author(s):  
Alvaro G. Bonilla ◽  
Jarred M. Williams ◽  
Alan S. Litsky ◽  
Elizabeth M. Santschi
2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Shinya Fujita ◽  
Yuji Arai ◽  
Kuniaki Honjo ◽  
Shuji Nakagawa ◽  
Toshikazu Kubo

Spontaneous osteonecrosis of the knee (SPONK) usually involves a single condyle, most often the medial femoral condyle (MFC). Involvement of the medial tibial plateau (MTP) is less common, occurring in about 2% of knees with SPONK. Early onset SPONK on the ipsilateral side of the medial compartment is very rare, with, to our knowledge, only four cases reported to date. We describe a very rare case of SPONK with early simultaneous development in the MFC and MTP. Serial plain radiographs and magnetic resonance imaging showed that SPONK in both condyles followed a similar progressive course. The pathological findings in these lesions were similar to those observed in subchondral insufficiency fractures.


2017 ◽  
Vol 45 (7) ◽  
pp. 1615-1621 ◽  
Author(s):  
Kang-Il Kim ◽  
Min-Chul Seo ◽  
Sang-Jun Song ◽  
Dae-Kyung Bae ◽  
Duk-Hyun Kim ◽  
...  

Background: Although cartilage regeneration after medial open-wedge high tibial osteotomy (HTO) has been described, there is a paucity of reports regarding which factors influence cartilage regeneration. Purpose: To document whether cartilage regeneration occurs in the previously degenerated medial compartment of arthritic knees after medial open-wedge HTO without concomitant cartilage procedures and to assess which predictive factors influence regeneration after HTO. Study Design: Case series; Level of evidence, 4 Methods: From February 2008 to January 2014, 104 consecutive knees were enrolled retrospectively that received medial open-wedge HTO with a medial locked plate system without any additional cartilage regeneration procedures and were followed by second-look arthroscopy for plate removal 2 years after surgery. The mean ± SD age at the time of index HTO was 56.3 ± 5.4 years. Cartilage status was graded at the time of initial HTO and second-look arthroscopy according to the International Cartilage Repair Society grading system, and regenerated articular cartilage was classified by the macroscopic staging system of Koshino et al at the time of second-look arthroscopy. Variables evaluated for possible association with regeneration of articular cartilage included age, sex, body mass index (BMI), American Knee Society score, mechanical tibiofemoral angle, medial proximal tibial angle, amount of correction angle, and degree of arthritis. Results: Per the International Cartilage Repair Society grading system, the lesions in the medial femoral condyle and the medial tibial plateau were improved in 54 knees (51.9%) and 36 knees (34.6%), respectively, at the time of second-look arthroscopy. According to the macroscopic grading system, partial and total regeneration of articular cartilage in the medial femoral condyle and the medial tibial plateau was observed in 75 knees (72%) and 57 knees (55%), respectively. Based on univariable logistic regression tests, regeneration of articular cartilage was associated with a smaller mean preoperative varus mechanical tibiofemoral angle (odds ratio [OR], 0.7; P = .023) and lower BMI (OR, 0.8; P = .026) for the medial femoral condyle and younger age (OR, 0.9; P = .048) and a larger mean correction angle (OR, 1.1; P = .023) for the medial tibial plateau. The mean preoperative knee and function scores were significantly improved at the last follow-up, but no correlation was found between the clinical outcomes and cartilage regeneration. Multiple logistic regression analysis for regeneration of articular cartilage showed lower BMI (OR, 0.7; P = .015) to be a significant predictor for the medial femoral condyle. Conclusion: Regeneration of degenerated articular cartilage in the medial compartment can be expected while correcting a varus deformity in arthritic knees after medial open-wedge HTO with a locked plate system without any additional cartilage regeneration procedures. Moreover, we suggest that medial open-wedge HTO in the medial arthritic knee with varus malalignment should be highly successful in terms of cartilage regeneration, especially for lower BMI patients.


1997 ◽  
Vol 119 (4) ◽  
pp. 379-385 ◽  
Author(s):  
T. A. Martens ◽  
M. L. Hull ◽  
S. M. Howell

This study was conducted to validate a new in vitro method to expose the medial compartment of the knee to be used in subsequent studies aimed at examining the load bearing capabilities of medial meniscal allografts. The new method involves an osteotomy and reattachment of the medial femoral condyle. The primary hypothesis was that the new method does not alter tibio-femoral contact pressure and area. To validate this method, the baseline contact pressure of the intact medial compartment was measured using a new nondestructive procedure for inserting pressure measurement film into the intact medial hemijoint. A secondary and related hypothesis was that incising the coronary ligament, a destructive method used by previous investigators to position pressure measurement film, alters the normal tibio-femoral contact pressure. To test these hypotheses, Fuji Prescale pressure-sensitive film was used to measure both tibio-femoral contact pressure and area within the medial compartment of the (1) intact knee, (2) the knee after osteotomizing and reattaching the medial femoral condyle, and (3) the osteotomized knee with an incised coronary ligament, using seven cadaver specimens. Measurements were taken at a compressive load of approximately two times body weight with the knee in 0, 15, 30, 45 deg of flexion. No significant differences between the intact and osteotomized knee were detected. Likewise, no significant differences were observed between the osteotomized knee and the osteotomized knee with an incised coronary ligament. These results confirm the utility of the new method in exposing the medial compartment for manipulation and placement of medial meniscal allografts in future studies examining the load-bearing characteristics of meniscal allografts.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Liang Yuan ◽  
Bin Yang ◽  
Xiaohua Wang ◽  
Bin Sun ◽  
Ke Zhang ◽  
...  

Purpose. Bony resection is the primary step during total knee arthroplasty. The accuracy of bony resection was highly addressed because it was deemed to have a good relationship with mechanical line. Patient-specific instruments (PSI) were invented to copy the bony resection references from the preoperative surgical plan during a total knee arthroplasty (TKA); however, the accuracy still remains controversial. This study was aimed at finding out the accuracy of the bony resection during PSI-assisted TKA. Methods. Forty-two PSI-assisted TKAs (based on full-length leg CT images) were analyzed retrospectively. Resected bones of every patient were given a CT scan, and three-dimensional radiographs were reconstructed. The thickness of each bony resection was measured with the three-dimensional radiographs and recorded. The saw blade thickness (1.27 mm) was added to the measurements, and the results represented intraoperative bone resection thickness. A comparison between intraoperative bone resection thickness and preoperatively planned thickness was conducted. The differences were calculated, and the outliers were defined as >3 mm. Results. The distal femoral condyle had the most accurate bone cuts with the smallest difference (median, 1.0 mm at the distal medial femoral condyle and 0.8 mm at the distal lateral femoral condyle) and the least outliers (none at the distal medial femoral condyle and 1 (2.4%) at the distal lateral femoral condyle). The tibial plateau came in second (median difference, 0.8 mm at the medial tibial plateau and 1.4 mm at the lateral tibial plateau; outliers, none at the medial tibial plateau and 1 (2.6%) at the lateral tibial plateau). Regardless of whether the threshold was set to >2 mm (14 (17.9%) at the tibial plateau vs. 12 (14.6%) at the distal femoral condyle, p > 0.05 ) or >3 mm (1 (1.3%) at the tibial plateau vs. 1 (1.2%) at the distal femoral condyle, p > 0.05 ), the accuracy of tibial plateau osteotomy was similar to that of the distal femoral condyle. Osteotomy accuracy at the posterior femoral condyle and the anterior femoral condyle were the worst. Outliers were up to 6 (15.0%) at the posterior medial femoral condyle, 5 (12.2%) at the posterior lateral femoral condyle, and 6 (15.8%) at the anterior femoral condyle. The percentages of overcut and undercut tended to 50% in most parts except the lateral tibial plateau. At the lateral tibial plateau, the undercut percentage was twice that of the overcut. Conclusion. The tibial plateau and the distal femoral condyle share a similar accuracy of osteotomy with PSI. PSI have a generally good accuracy during the femur and tibia bone resection in TKA. PSI could be a kind of user-friendly tool which can simplify TKA with good accuracy. Level of Evidence. This is a Level IV case series with no comparison group.


2019 ◽  
Vol 47 (2) ◽  
pp. 285-295 ◽  
Author(s):  
Alberto Grassi ◽  
Luca Macchiarola ◽  
Francisco Urrizola Barrientos ◽  
Juan Pablo Zicaro ◽  
Matias Costa Paz ◽  
...  

Background: Tibiofemoral anatomic parameters, such as tibial slope, femoral condyle shape, and anterior tibial subluxation, have been suggested to increase the risk of anterior cruciate ligament (ACL) reconstruction failure. However, such features have never been assessed among patients experiencing multiple failures of ACL reconstruction. Purpose: To compare the knee anatomic features of patients experiencing a single failure of ACL reconstruction with those experiencing multiple failures or with intact ACL reconstruction. Study: Case-control study; Level of evidence, 3. Methods: Twenty-six patients who experienced failure of revision ACL reconstruction were included in the multiple-failure group. These patients were matched to a group of 25 patients with failure of primary ACL reconstruction and to a control group of 40 patients who underwent primary ACL reconstruction with no failure at a minimum follow-up of 24 months. On magnetic resonance imaging (MRI), the following parameters were evaluated: ratio between the height and depth of the lateral and medial femoral condyles, the lateral and medial tibial plateau slopes, and anterior subluxation of the lateral and medial tibial plateaus with respect to the femoral condyle. The presence of a meniscal lesion during each procedure was evaluated as well. Anatomic, demographic, and surgical characteristics were compared among the 3 groups. Results: The patients in the multiple-failure group had significantly higher values of lateral tibial plateau slope ( P < .001), medial tibial plateau slope ( P < .001), lateral tibial plateau subluxation ( P < .001), medial tibial plateau subluxation ( P < .001), and lateral femoral condyle height/depth ratio ( P = .038) as compared with the control group and the failed ACL reconstruction group. Moreover, a significant direct correlation was found between posterior tibial slope and anterior tibial subluxation for the lateral ( r = 0.325, P = .017) and medial ( r = 0.421, P < .001) compartments. An increased anterior tibial subluxation of 2 to 3 mm was present in patients with a meniscal defect at the time of the MRI as compared with patients who had an intact meniscus for both the lateral and the medial compartments. Conclusion: A steep posterior tibial slope and an increased depth of the lateral femoral condyle represent a common finding among patients who experience multiple ACL failures. Moreover, higher values of anterior subluxation were found among patients with repeated failure and those with a medial or lateral meniscal defect.


1987 ◽  
Vol 24 (5) ◽  
pp. 444-448 ◽  
Author(s):  
A. M. Bendele

The sequential histopathologic alterations in femorotibial joints of partial meniscectomized male and female guinea pigs were evaluated at 1, 2, 3, 6, and 12 weeks post-surgery. Foci of moderate to severe cartilage degeneration were present in the medial tibial plateau and femoral condyle of the operated leg by 1 week post-surgery. At 2 weeks post-surgery, the cartilage degeneration in the operated legs was more extensive and there was evidence of early chondrophyte formation on the medial side of either the femur or tibia in three animals. Changes were progressively more severe at 3, 6, and 12 weeks. Focal areas of minimal to mild cartilage degeneration were in the medial tibial plateau of the contralateral nonoperated leg in some animals at 3 weeks post-surgery and in all animals at 12 weeks post-surgery. Changes in the contralateral leg of meniscectomized guinea pigs have not been described previously. Since cartilage degeneration was often severe by 1 week post-surgery, the model has limited utility for testing agents designed to modify the degenerative process in the operated leg. Milder, more slowly progressive lesions in the contralateral leg may be amenable to therapeutic intervention.


2019 ◽  
Vol 47 (11) ◽  
pp. 5671-5679 ◽  
Author(s):  
Leiyu Qiu ◽  
Jose Perez ◽  
Christopher Emerson ◽  
Carlos M. Barrera ◽  
Jianping Zhong ◽  
...  

Objective To evaluate changes in knee articular cartilage of novice half-marathon runners using magnetic resonance imaging T2 relaxation time mapping. Methods Healthy subjects were recruited from local running clubs who met the following inclusion criteria: (i) age 18–45 years; (ii) body mass index less than 30 kg/m2; (iii) had participated in one half-marathon or less (none within the previous 6 months); (iv) run less than 20 km/week; (v) no previous knee injury or surgery; (vi) no knee pain. T2 signals were measured pre- and post-race to evaluate the biochemical changes in articular cartilage after the subjects run a half-marathon. Results A significant increase in the mean ± SD T2 relaxation time was seen in the outer region of the medial tibial plateau (50.1 ± 2.4 versus 54.7 ± 2.6) and there was a significant decrease in T2 relaxation time in the lateral femoral condyle central region (50.2 ± 4.5 versus 45.4 ± 2.9). There were no significant changes in the patella, medial femoral condyle and lateral tibia articular surfaces. Conclusion An increase in T2 relaxation time occurs in the medial tibial plateau of novice half-marathon runners. This limited region of increased T2 values, when compared with complete medial compartment involvement seen in studies of marathon runners, may represent an association between distance run and changes seen in articular cartilage T2 values.


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