Does measuring the medial gap before bone resection in total knee arthroplasty provide optimum gap adjustment and prevent bone recutting? (original) (raw)
Related papers
Gap Balancing versus Measured Resection Technique for Total Knee Arthroplasty
Clinical Orthopaedics & Related Research, 2009
Multiple differing surgical techniques are currently utilized to perform total knee arthroplasty (TKA). We compared knee arthroplasties performed using either a measured resection or gap balancing technique to determine if either operative technique provides superior coronal plane stability as measured by assessment of the incidence and magnitude of femoral condylar lift-off. We performed 40 TKA using a measured resection technique (20 PCLretaining and 20 PCL-substituting) and 20 PCL-substituting TKA were implanted using gap balancing. All subjects were analyzed fluoroscopically while performing a deep knee bend. The incidence of coronal instability (femoral condylar lift-off) was then determined using a 3-D model fitting technique. The incidence of lift-off greater than 0.75 mm was 80% (maximum, 2.9 mm) and 70% (maximum, 2.5 mm) for the PCL-retaining and substituting TKA groups performed using measured resection versus 35% (maximum, 0.88 mm) for the gap-balanced group. Lift-off greater than 1 mm occurred in 60% and 45% of the PCL-retaining and-substituting TKA using measured resection versus none in the gap-balanced group. Rotation of the femoral component using a gap balancing technique resulted in better coronal stability which we suggest will improve functional performance and reduce polyethylene wear. An institution of the authors (Center for Musculoskeletal Research) and one author (DAD) have received funding from DePuy, Inc. (Warsaw, IN). Each author certifies that his or her institution has approved the reporting of these cases, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.
The accuracy of bony resection from patient-specific guides during total knee arthroplasty
Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2016
In patient-specifically instrumented (PSI) total knee arthroplasty, the correlation between the pre-operative surgical plan, accuracy of the cutting block, and intra-operative resection size is unclear. The aim of this study was to evaluate the ability to accurately execute the PSI surgical plan and to add to the merging information with respect to this technology with the hypothesis that the PSI blocks would demonstrate good accuracy with regard to the bony thickness of the resections. One hundred and thirty TKAs using PSI (MRI/long-leg radiographs) were retrospectively analysed. All surgeries were conducted via similar surgical approach and technique, with resection performed after guide placement and alignment assessment. The bony cut thicknesses of the medial (MTP) and lateral tibial plateau (LTP), distal medial (DM), distal lateral (DL), posterior medial (PM) and posterior lateral (PL) femur were measured with a vernier calliper. The measured resection thickness was subtracted ...
2010
Equalized rectangular extension and flexion gaps are considered desirable to ensure proper kinematics in total knee arthroplasty (TKA). We compared soft tissue balancing in TKAs performed using navigation-assisted gap-balancing (60 knees) and conventional measured resection (56 knees). The outlier of soft tissue balancing was defined as a gap difference[3 mm between the medial and lateral sides in 90°flexion and extension. Medial or lateral outliers in extension or flexion were observed in 12% (7 of 60) navigation TKAs and 25% (14 of 56) conventional TKAs (p = 0.028). There were more outliers in flexion-extension gap difference on the medial side in the conventional (23%) than in the navigation-assisted (5%) group (p = 0.025). However, the proportion of flexion gap difference, extension gap difference, and lateral gap difference outliers did not differ significantly between the two groups (n.s.). Additionally, clinicoradiologic outcomes were similar for the two groups except for the postoperative mechanical axis outlier (p = 0.012). Navigationassisted soft tissue balancing in TKA reduced not only the postoperative alignment outlier, but also the medial gap difference and achieved a more rectangular flexion and extension gap compared with conventional TKA.
Saw Cut Accuracy in Knee Arthroplasty–An Experimental Case-Control Study
Journal of Arthritis, 2015
Introduction: Navigated TKA (Total Knee Arthroplasty) has heightened awareness of mal-alignment in conventional TKA, as well as providing an accurate means of measuring alignment intra-operatively. Debate as to the importance and significance of alignment versus knee balance continues. Aim: To assess cutting error, and examine the hypothesises: • 'Slotted osteotomies are more accurate than non-slotted' • 'Second pass of the saw blade improves the accuracy of osteotomies' Method: Three pairs of fresh frozen human knees were prepared, exposed, and positioned as for primary TKA. Standard cutting guides were used in conjunction with a clinical navigation system, and the error (difference between the achieved resection, and the planned resection) in each osteotomy was measured. A second, tidying, pass of the saw blade was made and the error re-measured. Cutting guides were used with a slotted and un-slotted technique in left and right knees respectively. A single experienced surgeon performed all 96 osteotomies. Results: Slotted tibial osteotomies are significantly more accurate in the sagittal (p=0.01) and coronal (p=0.04) planes. Second pass osteotomies reduce variability in femoral (p=0.07) and tibial (p=0.17) osteotomies. Discussion: The bone cutting process is prone to high levels of random error that can result in implant malalignment, and thus predispose to aseptic loosening. Navigated TKA gives the operating surgeon the opportunity to check each osteotomy, and correct any error where necessary. In conventional TKA the use of dual pass, slotted osteotomies should provide improved accuracy.
The Journal of Arthroplasty, 2011
The authors evaluated 112 knees treated by total knee arthroplasty (TKA) using a navigation-assisted modified gap balancing technique. Initial mediolateral gap differences in extension and in 90°of flexion were measured after proximal tibia bone cutting. Final flexion and extension gaps were measured by checking distances under equal tension before prosthesis insertion. Amount of femoral bone cutting and external rotations of femoral components were found to depend on initial gaps. Patients with a final rectangular gap had greater knee flexion angles preoperatively and at 1 year after TKA. However, no differences were observed between the clinical and radiologic outcomes of knees with rectangular and nonrectangular gaps at 1 or 4 years after TKA. The study shows that the navigation-assisted modified gap balancing technique provides an effective means of achieving rectangular flexion and extension gaps during TKA.
The Knee, 2008
Many studies have shown that computer navigation in total knee arthroplasty aids the surgeon to place the prosthesis in a more accurate overall alignment. Bony resection creates the flexion and extension gaps; important in balancing the knee and implant selection in TKR. The computer plans the bone cuts but has variables that it cannot control: the surgeon, the saw blade thickness and oscillation, the accuracy of the jigs, movement of the pins, and the quality of initial mapping data inputted by the surgeon. The accuracy of computer navigated bone resections are validated on cadavers, but this is the first study to compare the predicted bone cuts to that physically resected during TKR. For 89 patients undergoing primary TKR, the bone cut from the distal femur and proximal tibia was measured using Vernier callipers and compared to the computer calculation of the same. Results show that computer measurement of the physical space left by the resected bone is accurate.
Indian Journal of Orthopaedics Surgery, 2021
Introduction: Total knee arthroplasty is one of the commonest musculoskeletol pain relieving surgery now a days. The long legacy of the different surgical techniques attracts the orthopaedic surgeons to opt for better results oriented techniques. Since in the mid 19s of origin of early knee arthroplasty to 2014 of gap balancing vs measured resection technique from US to the recent navigation & robotics era, different study showed improved results. For developing countries with financial constrains cost effective & results oriented more studies warranted. Objectives: To study the results of all femoral cuts first followed by tibial cuts as a measured resection technique based on anatomical landmarks followed by scientific soft tissue balancing for total knee arthroplasty. Materials and Methods: We have analyzed total (n= 126) the total knee replacement surgeries operated by our team during last 48 months retrospectively. Mean age was 66 years. All the Knee arthritis classified by Kel...
The Journal of Arthroplasty, 2019
Background: Total knee arthroplasty requires careful surgical technique to attain the goal of a wellaligned and symmetrically balanced knee. Soft tissue balance and correct femoral component rotation are paramount in achieving these goals. The two competing techniques to select femoral component rotation and soft tissue balance are the gap balance technique and the measured resection technique. Methods: We performed a randomized, prospective study to compare the two techniques in patients undergoing simultaneous bilateral total knee arthroplasty, whereby one technique was performed in each knee. Fifty (50) subjects were enrolled into the study. The inclusion criteria were osteoarthritic varus knee deformities with similar deformities in both knees. Subjects were followed up for a minimum of two years. Results: The knees balanced via the gap balance technique had significantly more posterior medial bone removed from the femur than those knees balanced via the measured resection technique (P < .001). Knees in the gap balance group tended to require more medial knee releases in extension and tended to have smaller sized femoral components as a result of cutting more bone from the femur in flexion. The modular tibial polyethylene bearing tended to be thicker in the gap balance group. Despite these differences, average knee flexion and functional revised Oxford Knee Scores at 2-year follow-up were not statistically different. Conclusion: At 2-year follow-up, there were no differences between the function and scores using the two techniques. Long-term follow-up will be necessary to evaluate any differences in long-term durability.
The Journal of Arthroplasty
Background: Total knee arthroplasty requires careful surgical technique to attain the goal of a wellaligned and symmetrically balanced knee. Soft tissue balance and correct femoral component rotation are paramount in achieving these goals. The two competing techniques to select femoral component rotation and soft tissue balance are the gap balance technique and the measured resection technique. Methods: We performed a randomized, prospective study to compare the two techniques in patients undergoing simultaneous bilateral total knee arthroplasty, whereby one technique was performed in each knee. Fifty (50) subjects were enrolled into the study. The inclusion criteria were osteoarthritic varus knee deformities with similar deformities in both knees. Subjects were followed up for a minimum of two years. Results: The knees balanced via the gap balance technique had significantly more posterior medial bone removed from the femur than those knees balanced via the measured resection technique (P < .001). Knees in the gap balance group tended to require more medial knee releases in extension and tended to have smaller sized femoral components as a result of cutting more bone from the femur in flexion. The modular tibial polyethylene bearing tended to be thicker in the gap balance group. Despite these differences, average knee flexion and functional revised Oxford Knee Scores at 2-year follow-up were not statistically different. Conclusion: At 2-year follow-up, there were no differences between the function and scores using the two techniques. Long-term follow-up will be necessary to evaluate any differences in long-term durability.