Knee Surgery & Related Research最新文献

Objective: Knee arthritis associated with tibial stress fractures represents an uncommon and difficult clinical scenario to treat. The use of long, fluted tibial extension rods has been vital in the management of such cases owing to immediate fracture stability and single-stage surgery without the need to open the fracture site. This study investigates clinical and radiological outcomes following total knee arthroplasty using a tibial extension stem in cases of knee osteoarthritis with tibial stress fracture.

Methods: From February 2015 to December 2020, 17 patients who had total knee arthroplasty implanted with a long stemmed tibial component were included in the study. Patient data were analyzed for knee range of motion, deformities, Knee Society score, knee function score, and time to fracture union in the pre- and postoperative periods.

Results: The mean follow-up duration was 22.7 ± 11.68 months (range 12-60 months), and mean time to fracture healing was 10.23 ± 2.81 weeks (range 8-20 weeks). The preoperative mean fixed flexion deformity improved from 8.53 ± 3.43° to a mean of 0.29°, and knee flexion improved from 79.4 ± 13.90° to 125.29 ± 8.74° on postoperative assessment. The Knee Society score improved from a mean preoperative score of 18.94 ± 5.55 (range 8-28) to 89.41 ± 7.5 (range 74-102, p value < 0.001). Similarly, the knee function score improved significantly from a mean preoperative score of 15.5 ± 4.48 (range 8-26) to a mean of 85 ± 6.09 (range 72-94, p value < 0.001).

Conclusion: Total knee arthroplasty using long tibial extenders has been an effective and safe surgical option for patients with advanced osteoarthritis with tibial stress fractures.

Purpose: The quadriceps muscle has a positive effect on anterior knee pain. However, its effect on the patellofemoral (PF) cartilage in patients with end-stage knee osteoarthritis is unknown. The present study aimed to evaluate whether the quadriceps muscle area had a positive effect on the PF cartilage and whether this muscle had a positive effect on the clinical scores.

Materials and methods: Patients with confirmed cartilage status and clinical scores who underwent total knee arthroplasty (TKA) were included. The PF cartilage status was evaluated during TKA. The thickness and the area of the quadriceps muscle were measured using a knee computed tomography scan obtained before the surgery. The Q-angle, hip-knee-ankle angle, alignment, and Insall-Salvati ratio were measured by radiography.

Results: Altogether, 204 patients were included in the study. Logistic regression was performed including factors associated with PF cartilage lesions. The regression model was found to be statistically significant (Hosmer-Lemeshow test, χ² = 0.493). A smaller hip-knee-ankle (HKA) angle was associated with a higher incidence of PF cartilage lesions (p = 0.033) and only the alignment had an effect on the PF cartilage lesions. PF cartilage lesions did not correlate with the clinical scores. A thicker medial portion of the quadriceps muscle was associated with a significantly higher Knee Society Knee Score (KSKS) (p = 0.028).

Conclusions: Quadriceps muscle thickness and area, Q-angle, and patellar height were not associated with PF cartilage lesions, while a smaller HKA angle was associated with PF cartilage lesions. The presence of PF cartilage lesions did not affect the clinical symptoms. However, a thicker medial portion of the quadriceps muscle was associated with a higher KSKS.

Background: During revision total knee arthroplasty (TKA), knee joint line restoration may be difficult due to bone loss or structural changes. Although bony landmarks are consistent and can be used as references, there are limited data in Asian patients. We studied the knee joint line related to bony landmarks of the knee in a Thai population.

Materials and methods: Magnetic resonance imaging (MRI) of 140 healthy knees of Thai patients (70 males, 70 females) were investigated. In all knees, a perpendicular line from knee joint line to the medial epicondyle (distance A) and the lateral epicondyle (distance B) in the coronal plane were measured. In the sagittal plane, a perpendicular line from the knee joint line to the fibular head (distance C), the tibial tubercle (distance D), and the inferior patellar pole (distance E) were measured. The femoral transepicondylar width (FW) was measured along the transepicondylar axis. The ratios of distances A, B, C, D, and E related to FW were evaluated (epicondylar ratio).

Results: The mean and standard deviation (SD) of distances A, B, C, D, E, and FW were 27.1 ± 2.7 mm, 21.7 ± 2.5 mm, 12.6 ± 3 mm, 21.3 ± 3.6 mm, 7.6 ± 4.8 mm, and 76.7 ± 3.99, respectively. There was wide variation of measured values, with statistically significant differences between genders in distances A, B, C, and FW. The mean and SD of epicondylar ratios A/FW, B/FW, C/FW, D/FW, and E/FW were 0.35 ± 0.02, 0.29 ± 0.02, 0.16 ± 0.05, 0.28 ± 0.04, and 0.09 ± 0.04, respectively. All epicondylar ratios demonstrated less variation than all measured distances, with statistical differences between genders in the A/FW and D/FW ratios. However, the B/FW ratio had the highest consistent mean value. In addition, it had narrower SD than the rest (0.29 ± 0.02; range, 0.22-0.33).

Conclusions: In Thai knees, the measured distances from bony landmarks to the knee joint line had higher variation than the epicondylar ratio. Among all studied epicondylar ratios, the ratio between lateral epicondyle to joint line distance (distance B)/FW demonstrated the narrowest range of mean and SD values; therefore, this could be the most reliable landmark for intraoperative knee joint line verification by multiplying the FW of the patient by 0.29 to get distance B in that patient.

Purpose: The optimal practice of patellar management in total knee arthroplasty (TKA) remains controversial. This systematic review was conducted to compare patella-related (1) patient-reported outcome measures (PROMs), (2) clinical outcomes, and (3) reoperation rates after TKA with patellar resurfacing (PR) and nonresurfacing (NPR) in single patients undergoing bilateral patellar procedures during simultaneous bilateral TKA.

Methods: This review included prospective bilateral randomized trials investigating patella-related PROMs, clinical outcomes, and reoperation (secondary resurfacing and patellar component revision) and other patella-related complications in single patients undergoing randomly assigned PR and NPR during bilateral TKA.

Results: Six studies were included. There was no difference in PROMs between PR and NPR in five studies, whereas PR was found to be superior to NPR in one study. Five studies reported similar functional outcomes and complication rates between PR and NPR, while one study found better clinical outcomes and a lower complication rate in PR. Between-group secondary resurfacing and patellar revision rates were similar in all studies.

Conclusions: The majority of patients who underwent bilateral patellar procedures could not tell the difference between PR and NPR following bilateral TKA. There were no differences in clinical outcomes or reoperation and complication rates between PR and NPR. No evidence was found to support routine PR.

Level of evidence: Therapeutic Level 1.

Medial opening wedge high tibial osteotomy (MOWHTO) is a widely used surgical treatment option for medial compartmental osteoarthritis with varus deformity. It is important that proper lower limb alignment is achieved. However, there has been no consensus about an optimal alignment in MOWHTO. Most studies suggest that achieving valgus alignment is necessary, and recent studies support slight valgus mechanical alignment of less than 3° of mechanical femorotibial angle. Overcorrection and undercorrection is not recommended for achieving good surgical outcomes. To prevent undercorrection and overcorrection in MOWHTO, the method of placing the weight-bearing line in the target range must be precise. There are several ways to place a weight-bearing line within the target range. While the most important factor for a successful MOWHTO is achieving an ideal mechanical axis correction, there are a few other factors to consider, including joint line obliquity, posterior tibial slope, ligament balancing, and patellar height. Several factors exist that lead to undercorrection and overcorrection. Preoperative amount of varus deformity, lateral hinge fracture, and fixation failure can result in undercorrection, while medial soft tissue laxity and the amount of correction angle and target point beyond hypomochlion can result in overcorrection. This study aimed to review the literature on optimal alignment in MOWHTO and report on the factors to be considered to prevent correction errors and how to achieve an optimal alignment.

Purpose: In navigated TKA, the risk of notching is high if femoral component sagittal positioning is planned perpendicular to the sagittal mechanical axis of femur (SMX). We intended to determine if, by opting to place the femoral component perpendicular to distal femur anterior cortex axis (DCX), notching can be reduced in navigated TKA.

Methods: We studied 171 patients who underwent simultaneous bilateral computer-assisted TKA. Femoral component sagittal positioning was planned perpendicular to SMX in one knee (Femur Anterior Bowing Registration Disabled, i.e. FBRD group) and perpendicular to DCX in the opposite knee (Femur Anterior Bowing Registration Enabled, i.e. FBRE group). Incidence and depth of notching were recorded in both groups. For FBRE knees, distal anterior cortex angle (DCA), which is the angle between SMX and DCX, was calculated by the computer.

Results: Incidence and mean depth of notching was less (p = 0.0007 and 0.009) in FBRE versus FBRD group, i.e. 7% versus 19.9% and 0.98 mm versus 1.53 mm, respectively. Notching was very high (61.8%) in FBRD limbs when the anterior bowing was severe (DCA > 3°) in the contralateral (FBRE) limbs.

Conclusion: Notching was less when femoral component sagittal positioning was planned perpendicular to DCX, in navigated TKA.

Level of evidence: Therapeutic level II.

Purpose: Navigated total knee arthroplasty (TKA) improves implant alignment by providing feedback on resection parameters based on femoral and tibial cutting guide positions. However, saw blade thickness, deflection, and cutting guide motion may lead to final bone cuts differing from planned resections, potentially contributing to suboptimal component alignment. We used an imageless navigation device to intraoperatively quantify the magnitude of error between planned and actual resections, hypothesizing final bone cuts will differ from planned alignment.

Materials and methods: A retrospective study including 60 consecutive patients undergoing primary TKA using a novel imageless navigation device was conducted. Device measurements of resection parameters were obtained via attachment of optical trackers to femoral and tibial cutting guides prior to resection. Following resection, optical trackers were placed directly on the bone cut surface and measurements were recorded. Cutting guide and bone resection measurements of both femoral and tibial varus/valgus, femoral flexion, tibial slope angles, and both femoral and tibial medial and lateral resection depths were compared using a Student's t-test.

Results: Femoral cutting guide position differed from the actual cut by an average 0.6 ± 0.5° (p = 0.85) in the varus/valgus angle and 1.0 ± 1.0° (p = 0.003) in the flexion/extension angle. The difference between planned and actual cut measurements for medial and lateral femoral resection depth was 1.1 ± 1.1 mm (p = 0.32) and 1.2 ± 1.0 mm (p = 0.067), respectively. Planned cut measurements based on tibial guide position differed from the actual cut by an average of 0.9 ± 0.8° (p = 0.63) in the varus/valgus angle and 1.1 ± 1.0° (p = 0.95) in slope angle. Measurement of medial and lateral tibial resection depth differed by an average of 0.1 ± 1.8 mm (p = 0.78) and 0.2 ± 2.1 mm (p = 0.85), respectively.

Conclusions: Significant discrepancies between planned and actual femoral bone resection were demonstrated for flexion/extension angle, likely the result of cutting error. Our data highlights the importance of cut verification postresection to confirm planned resections are achieved, and suggests imageless navigation may be a source of feedback that would allow surgeons to intraoperatively adjust resections to achieve optimal implant alignment.

Purpose: Suspensory devices are extensively used in the management of anterior cruciate ligament (ACL) tear. They include fixed- and adjustable-loop devices. There are only a few studies comparing the efficacy of these two devices in the available literature. Therefore, the aim of this study is to compare clinical outcomes between the adjustable-loop device (group I) and fixed-loop device (group II).

Materials and methods: This was a prospective randomized study. Both groups were equivalent in demographic, preoperative, and intraoperative variables. Twenty-three patients underwent femoral side graft fixation with adjustable-loop and 20 with fixed-loop devices. Four patients were lost to follow-up. Assessment of clinical outcome was done with International Knee Documentation Committee (IKDC) score, Lysholm score, and knee stability tests (Lachman test and pivot shift test). Patient evaluation was performed preoperatively and finally postoperatively 2 years after surgery.

Results: Postoperative IKDC scores of group I and II were 91.9 ± 3.6 and 91.5 ± 3.6, respectively, and Lysholm scores were 91.0 ± 3.6 and 91.4 ± 3.5, respectively, after 2 years; however, the difference in the outcomes was statistically insignificant (p > 0.05). Twenty patients (87%) in group I and 17 patients (85%) in group II had a negative Lachman test (p = 0.8). Twenty-two patients (95.7%) in group I and 19 patients (95%) in group II had a negative pivot shift test (p = 0.9).

Conclusion: ACL reconstruction with fixed- and adjustable-loop suspensory devices for graft fixation gives equivalent and satisfactory clinical results.

Level of evidence: 1.