Changes in Joint Gap Balances between Intra- and Postoperation in Total Knee Arthroplasty

Achieving correct soft tissue balance and preparing equal and rectangular extension and flexion joint gaps are crucial goals of TKA. Intraoperative gap balances would change postoperatively; however, changes in joint gap balances between pre- and postoperation remain unclear. To explore these changes associated with TKA, we prospectively investigated 21 posterior cruciate ligament retaining TKAs for varus knees. Intraoperative extension gap balance (iEGB) was 2.6 ± 2.0° varus versus postoperative extension gap balance (pEGB) of 0.77 ± 1.8° valgus (P<0.01), while no significant difference between intraoperative flexion gap balance (iFGB) and postoperative flexion gap balance (pFGB) was observed. We also explored correlations between intraoperative and postoperative gap balances but found no significant correlations. These observations indicate that (i) surgeons should avoid excessive release of the medial soft tissue during TKA for varus knees and (ii) intraoperative gap balance may not be necessarily reflected on postoperative gap balance.

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Accuracy of total knee arthroplasty using the modified gap technique based on the bone gap: an evaluation of the bone gap with a distal femoral trial component

Arthroplasty ◽

10.1186/s42836-021-00072-w ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Goki Kamei ◽

Shigeki Ishibashi ◽

Koki Yoshioka ◽

Satoru Sakurai ◽

Hiroyuki Inoue ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Soft Tissue ◽

Knee Arthroplasty ◽

Distal Femur ◽

Gap Size ◽

Flexion Gap ◽

Gap Technique ◽

Joint Gap ◽

Total Knee ◽

The Mean

Abstract Background In total knee arthroplasty (TKA) using the modified gap technique, the soft-tissue balance is measured after osteotomy of the distal femur and proximal tibia (conventional bone gap). However, after osteotomy, the flexion gap size during 90° knee flexion may be larger than that observed after implantation. The tension of the lateral compartment during 90° flexion may also be reduced after osteotomy of the distal femur. We manufactured a distal femoral trial component to reproduce the condition after implantation and prior to posterior condyle osteotomy. This study aimed to evaluate the effect of the trial component on the flexion gap. Methods This prospective study included 21 consecutive patients aged 78 years with medial osteoarthritis who underwent cruciate-retaining TKA between February 2017 and March 2018. The postoperative flexion gap size and inclination during 90° flexion were compared between cases with and without the trial component. Results The mean joint gap size with the trial component (13.4 ± 0.80 mm) was significantly smaller than that without the trial component (14.7 ± 0.84 mm). The mean gap inclination angle with the trial component (3.7° ± 0.62°) was significantly smaller than that without the trial component (5.5° ± 0.78°). Conclusions In the present study, the joint gap size and medial tension were significantly reduced after the trial component had been set. Accurate measurement of the soft-tissue balance is an important factor in the modified gap technique, and this method using a distal femoral trial component can offer better outcomes than those achieved with conventional methods.

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Posterior cruciate ligament resection in total knee arthroplasty

The Bone & Joint Journal ◽

10.1302/0301-620x.101b10.bjj-2018-1428.r2 ◽

2019 ◽

Vol 101-B (10) ◽

pp. 1230-1237 ◽

Cited By ~ 14

Author(s):

Babar Kayani ◽

Sujith Konan ◽

Saman Horriat ◽

Mazin S. Ibrahim ◽

Fares S. Haddad

Keyword(s):

Total Knee Arthroplasty ◽

Posterior Cruciate Ligament ◽

Knee Arthroplasty ◽

Cruciate Ligament ◽

Limb Alignment ◽

Flexion Gap ◽

Flexion Extension ◽

Total Knee ◽

The Mean ◽

Extension Gap

Aims The aim of this study was to assess the effect of posterior cruciate ligament (PCL) resection on flexion-extension gaps, mediolateral soft-tissue laxity, fixed flexion deformity (FFD), and limb alignment during posterior-stabilized (PS) total knee arthroplasty (TKA). Patients and Methods This prospective study included 110 patients with symptomatic osteoarthritis of the knee undergoing primary robot-assisted PS TKA. All operations were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess gaps before and after PCL resection in extension and 90° knee flexion. Measurements were made after excision of the anterior cruciate ligament and prior to bone resection. There were 54 men (49.1%) and 56 women (50.9%) with a mean age of 68 years (sd 6.2) at the time of surgery. The mean preoperative hip-knee-ankle deformity was 4.1° varus (sd 3.4). Results PCL resection increased the mean flexion gap significantly more than the extension gap in the medial (2.4 mm (sd 1.5) vs 1.3 mm (sd 1.0); p < 0.001) and lateral (3.3 mm (sd 1.6) vs 1.2 mm (sd 0.9); p < 0.01) compartments. The mean gap differences after PCL resection created significant mediolateral laxity in flexion (gap difference: 1.1 mm (sd 2.5); p < 0.001) but not in extension (gap difference: 0.1 mm (sd 2.1); p = 0.51). PCL resection significantly improved the mean FFD (6.3° (sd 4.4) preoperatively vs 3.1° (sd 1.5) postoperatively; p < 0.001). There was a strong positive correlation between the preoperative FFD and change in FFD following PCL resection (Pearson’s correlation coefficient = 0.81; p < 0.001). PCL resection did not significantly affect limb alignment (mean change in alignment: 0.2° valgus (sd 1.2); p = 0.60). Conclusion PCL resection creates flexion-extension mismatch by increasing the flexion gap more than the extension gap. The increase in the lateral flexion gap is greater than the increase in the medial flexion gap, which creates mediolateral laxity in flexion. Improvements in FFD following PCL resection are dependent on the degree of deformity before PCL resection. Cite this article: Bone Joint J 2019;101-B:1230–1237

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The Disproportionate Increase of the Intraoperative Flexion and Extension Gap Space after Posterior Cruciate Ligament Resection in Total Knee Arthroplasty

Journal of Clinical Medicine ◽

10.3390/jcm10184228 ◽

2021 ◽

Vol 10 (18) ◽

pp. 4228

Author(s):

Kao-Chang Tu ◽

Han-Ting Shih ◽

Shih-Chieh Tang ◽

Cheng-Hung Lee ◽

Wei-Jen Liao ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Posterior Cruciate Ligament ◽

Knee Arthroplasty ◽

Cruciate Ligament ◽

Open Chain ◽

Flexion Gap ◽

Closed Chain ◽

Before And After ◽

Total Knee ◽

Extension Gap

Purpose: Maintaining gap balance is critical for total knee arthroplasty (TKA). This study aimed to elucidate if the extension–flexion gaps would be changed with posterior cruciate ligament (PCL) intact (PI) and PCL resection (PR) during TKA. The flexion gaps were measured using two methods, open-(Fo) and closed-chain position (Fc), based on the definition of kinetic chain position, respectively. Methods: This retrospective study enrolled a total of 33 patients who underwent posterior-stabilized (PS) TKA for symptomatic advanced osteoarthritis of knees. After bone cuts were completed, the extension–flexion gaps before and after PCL resection during TKA were measured using a calibrated tensioning device set at a 100 Nm distraction force. To further differentiate the effect of thigh weight on the 90° flexion gap, two varied methods of examination, either in closed chain (Fc) or open chain (Fo) were performed. Results: The increases in the 90° knee flexion gap after PCL resection were measured by both methods, i.e., ΔFc (PR-Fc—PI-Fc): 2.04 ± 2.06 mm, p < 0.001; and mean ΔFo (PR-Fo—PI-Fo): 1.64 ± 1.36 mm, p < 0.001. However, there were no differences between ΔFc and ΔFo before and after PCL resection. A greater amount of flexion gap was identified in open chain than in closed chain after PCL resection, and the PR-Fo and PR-Fc were 14.36 ± 3.13 and 11.40 ± 3.47 (p < 0.001), respectively. Conclusions: The resection of PCL during TKA distinctly increased the flexion gap, but not the extension gap. This disproportionate increase of the gap will cause a gap balance mismatch. The tensioning maneuver in open-chain was more effective to detect the gap differences than in closed-chain before and after PCL resection during TKA.

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Soft tissue impingement at the femorotibial joint after a posterior cruciate ligament-retaining total knee arthroplasty

Medicine: Case Reports and Study Protocols ◽

10.1097/md9.0000000000000073 ◽

2021 ◽

Vol 2 (7) ◽

pp. e0073

Author(s):

Mitsuhiro Nakamura ◽

Yoshinori Soda ◽

Nobuo Adachi

Keyword(s):

Total Knee Arthroplasty ◽

Soft Tissue ◽

Posterior Cruciate Ligament ◽

Knee Arthroplasty ◽

Cruciate Ligament ◽

Soft Tissue Impingement ◽

Posterior Cruciate Ligament Retaining ◽

Total Knee ◽

Femorotibial Joint

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Is Standing Coronal Long-Leg Alignment View Effective in Predicting the Extent of Medial Soft Tissue Release in Varus Deformity during Total Knee Arthroplasty?

The Journal of Knee Surgery ◽

10.1055/s-0040-1721787 ◽

2021 ◽

Author(s):

Mohammadreza Minator Sajjadi ◽

Mohammad Ali Okhovatpour ◽

Yaser Safaei ◽

Behrooz Faramarzi ◽

Reza Zandi

Keyword(s):

Total Knee Arthroplasty ◽

Soft Tissue ◽

Knee Arthroplasty ◽

Varus Deformity ◽

Soft Tissue Release ◽

Varus Knee ◽

Significant Difference ◽

Leg Alignment ◽

Total Knee ◽

Group 2

AbstractThe aim of this study was to assess the predictive value of the femoral intermechanical-anatomical angle (IMA), mechanical lateral distal femoral angle (mLDFA), medial proximal tibia angle (MPTA), femorotibial or varus angle (VA), and joint line convergence angle (CA) in predicting the stage of the medial collateral ligament (MCL) during total knee arthroplasty (TKA) of varus knee. We evaluated 229 patients with osteoarthritic varus knee who underwent primary TKA, prospectively. They were categorized in three groups based on the extent of medial soft tissue release that performed during TKA Group 1, osteophytes removal and release of the deep MCL and posteromedial capsule (stage 1); Group 2, the release of the semimembranosus (stage 2); and Group 3, release of the superficial MCL (stage 3) and/or the pes anserinus (stage 4). We evaluated the preoperative standing coronal hip-knee-ankle alignment view to assessing the possible correlations between the knee angles and extent of soft tissue release. A significant difference was observed between the three groups in terms of preoperative VA, CA, and MPTA by using the Kruskal–Wallis test. The extent of medial release increased with increasing VA and CA as well as decreasing MPTA in preoperative long-leg standing radiographs. Finally, a patient with a preoperative VA larger than 19, CA larger than 6, or MPTA smaller than 81 would need a stage 3 or 4 of MCL release. The overall results showed that the VA and MPTA could be useful in predicting the extent of medial soft tissue release during TKA of varus knee.

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The Impact of Intraoperative Gap Difference Between Extension and Flexion on Perception of Joint Function After Total Knee Arthroplasty: a Comparative Retrospective Study

10.21203/rs.3.rs-569511/v1 ◽

2021 ◽

Author(s):

Tomohiro Okayoshi ◽

Yoshinori Okamoto ◽

Hitoshi Wakama ◽

Shuhei Otsuki ◽

Masashi Neo

Keyword(s):

Total Knee Arthroplasty ◽

Retrospective Study ◽

Soft Tissue ◽

Knee Joint ◽

Predictive Factors ◽

Knee Arthroplasty ◽

Difference Threshold ◽

Joint Function ◽

Flexion Gap ◽

Total Knee

Abstract Background: The argument presupposes that intra-operative soft tissue balance is associated with patient-reported outcome measures after total knee arthroplasty (TKA). Our aim was to assess the association between the extension-to-flexion gap and patients’ reported perception of knee joint function.Methods: This was a retrospective study of 60 cases of primary cruciate-retaining TKAs performed for the treatment of medial-compartment knee osteoarthritis, at a mean follow-up of 2.6 (range, 2.0–5.2) years. Knee perception was evaluated by asking patients whether they considered their knee joint as “natural” (grade I) or “artificial”, with or without restrictions (grades II–V). The following factors were compared between the two groups: age, sex, and the extension-to-flexion gap difference. A multiple logistic regression analysis was used to identify predictive factors of an artificial knee joint perception. A receiver operating characteristic curve analysis was used to identify cut-off values of predictive factors. Result: Compared to a natural knee joint perception (26 knees, 43%), an artificial perception (34 knees, 57%) was associated with a smaller gap difference at the distraction force of 20 lbf (p < .001), 30 lbf (p = .022), and 40 lbf (p = .038), a lower EuroQol 5-Dimension score (p = .029), and self-reported joint health (Knee injury and Osteoarthritis Outcome Score-Joint Replacement [KOOS-JR], p = .032). A gap difference <1.0 mm was a predictive of an artificial perception (odds ratio, 1.63; 95% confidence interval, 1.33–4.54; p < .001). A cut-off gap difference of 0.99 mm at 20 lbf predicted an artificial perception with a sensitivity of 81.5% and a specificity of 87.9%. Post-operative satisfaction (p < .001), KOOS-JR (p < .001), patient’s joint perception (p = .006), pain (p = .015), and EuroQol 5-Dimension (p = .032) differed between the two groups when the gap difference threshold was set to 1.0 mm.Conclusion: Careful balancing of soft tissue during TKA to achieve an extension-to-flexion gap ≥ 1.0 mm can improve patients’ perception of knee joint function and quality of life.

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