Retaining the medial collateral ligament in high tibial medial open-wedge osteotomy mostly results in post-operative intra-articular gap reduction

Release or transection of superficial medial collateral ligament during open-wedge high tibial osteotomy demonstrated similar clinical outcomes and valgus laxity

PURPOSE

To analyse whether valgus laxity and clinical outcomes differ depending on whether the superficial medial collateral ligament (sMCL) is released or transected during medial open-wedge high tibial osteotomy (MOWHTO).

METHODS

Consecutive patients who underwent MOWHTO and subsequent radiological follow-up for at least 2 years were retrospectively evaluated. The patients were divided into release and transection groups, according to the sMCL manipulation technique. Each patient was assessed for the following variables on valgus stress radiographs taken before surgery and at the 12- and 24-month follow-ups: the absolute value of valgus (ABV) and side-to-side difference (SSD) between the affected and normal sides. The differences between preoperative SSD and those at 12 and 24 months were respectively calculated and defined as delta SSD (ΔSSD). The Visual Analogue Scale, Lysholm knee, International Knee Documentation Committee subjective, and Knee Injury and Osteoarthritis Outcome scores were used to evaluate patient-reported outcomes.

RESULTS

Eighty-five patients were included in the study. Forty-two patients (49.6%) underwent sMCL release, and the remaining 43 patients (50.4%) underwent sMCL transection. No significant differences were observed in the ABV and SSD of valgus laxity at the different time points between the two groups (n.s.). Furthermore, no significant differences were observed in the ΔSSD at the 12- and 24-month follow-ups between the two groups (n.s.). Significant improvement from preoperative values was observed in all patient-reported outcomes (p < 0.001), with no significant differences between the two groups at any time point (n.s.).

CONCLUSION

Significant improvements in clinical outcomes were observed, regardless of the technique used. Postoperative valgus laxity did not occur with either technique. The transection technique, which can be performed more simply and quickly, demonstrated similar clinical outcomes and valgus laxity to the release technique.

LEVEL OF EVIDENCE

Level III.

Analysis of the determinant factor of the medial joint space width after medial opening wedge high tibial osteotomy

INTRODUCTION

The decrease in the medial joint space width (MJSW) in patients with osteoarthritis (OA) is proportional to the degree of arthritis. The purpose of this study was to evaluate the affecting factors of the MJSW by serial radiologic assessment after medial open wedge high tibial osteotomy (MOW-HTO).

MATERIALS AND METHODS

Between March 2014 and March 2019, 162 MOW-HTO knees that underwent serial radiologic assessment and follow-up MRI were enrolled. Changes in the MJSW were analyzed by dividing into three groups: group I, low quartile (< 25%); II, middle quartile (25-75%); and III, high quartile (> 75%), according to the magnitude of the MJSW. The correlation between the MJSW and weight-bearing line ratio (WBLR), hip knee ankle angle (HKA), joint line convergence angle (JLCA), medial proximal tibial angle (MPTA), mechanical lateral distal femoral angle (m-LDFA), joint line orientation angle (JLOA), and MRI cartilage status was analyzed. Multiple linear regression analysis was used to analyze factors affecting the amount of change in the MJSW. The clinical outcome was also correlated with the MJSW.

RESULTS

The amount of change in the JLCA, which has the largest beta value (weight-bearing standing anteroposterior (AP) view and 45° flexion posteroanterior view (Rosenberg view) β =  - 0.699 and β = -5.221, both p < 0.001, respectively), had the greatest contribution to the change in the MJSW. The WBLR was also related (standing AP and Rosenberg β = 0.177 and β = 0.264, p = 0.015 and p = 0.004, respectively). There was no statistical difference between the amount of change in the MJSW and the change in cartilage. The clinical outcomes did not differ between the groups.

CONCLUSION

The JLCA was the most important contributing factor for the MJSW, followed by WBLR. This contribution was more pronounced in Rosenberg view than standing AP view. Changes in cartilage status were not related to the MJSW and JLCA. The clinical outcome was not related to the MJSW, either. Level of evidence Cohort study; level III.

Transverse osteotomy closer to tibial plateau is associated with larger postoperative change in valgus laxity after open-wedge high tibial osteotomy

PURPOSE

To identify the factors impacting changes in valgus laxity between before and after open-wedge high tibial osteotomy (OW-HTO) using quantitative valgus stress radiographs.

METHODS

A total of 40 knees from 38 patients who underwent OW-HTO were assessed. The study population comprised 14 men and 24 women, with a mean age of 61.5 years. Valgus stress radiographs before and 1 year after OW-HTO were performed using a Telos device. The difference between pre- and postoperative joint line convergence angle (JLCA) was expressed as ΔJLCA (post-pre). As indicators of the proximal detachment of superficial medial collateral ligament (sMCL) on radiographs, two distances were defined: the distance from the level of the osteotomy starting point to the tangent line of the proximal tibial plateau (Distance A), or to the medial edge of the proximal tibial plateau (Distance B). Correlations between ΔJLCA and radiographic parameters or KOOS sub-scores were assessed using Spearman's rank correlation coefficient analysis. Receiver operator curves were generated to evaluate the predictive strength of the significant factor for an increase in ΔJLCA > 1°.

RESULTS

Pre-operative OA severity consisted of Kellgren-Lawrence grade 2 (n = 18), 3 (n = 16), and 4 (n = 6). The average ΔJLCA (post-pre) was 0.5°, and ranged from - 1.4° to + 3.0°. The maximum systemic measurement error and limits of agreement were 0.07° and 0.20°, respectively. There were significant correlations between ΔJLCA and Distance A (36.9 ± 3.9 mm, R =  - 0.46, p = 0.002), between ΔJLCA and Distance B (39.9 ± 4.0 mm, R =  - 0.49, p = 0.001). The cut-off value for Distance A was determined to be 35 mm below the tibial plateau; the AUC was 0.804, with a sensitivity of 0.75 and a specificity of 0.82. Distance B correlated strongly with Distance A (R = 0.96, p < 0.001). There was no significant correlation between ΔJLCA and KOOS sub-scores 1 year after OW-HTO.

CONCLUSIONS

Transverse osteotomy closer to tibial plateau was associated with larger valgus joint laxity postoperatively. This finding implies that sMCL proximal detachment, which was related to the level of the osteotomy starting point on the proximal tibia, potentially affected postoperative valgus laxity.

LEVEL OF EVIDENCE

IV.

Medial unicompartmental knee replacement is a viable treatment option after failed high tibial osteotomy: a systematic review

Purpose

Methods

Results

Conclusions

Does Transection of the Superficial MCL During HTO Result in Progressive Valgus Instability? [Formula: see text]

BACKGROUND

During high tibial osteotomy (HTO), the superficial medial collateral ligament (sMCL) is cut or released at any degree to expose the osteotomy site and achieve the targeted alignment correction according to the surgeon's preference. However, it is still unclear whether transection of sMCL increases valgus laxity.

PURPOSE

We aimed to assess the outcomes and safety of sMCL transection, especially focusing on iatrogenic valgus instability.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Seventy-two patients (89 knees) who underwent medial open wedge HTO (MOWHTO) with transection of the sMCL between October 2013 and September 2018 were retrospectively investigated. Clinical evaluations, including the International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Tegner and Lysholm scores, were performed preoperatively and at 2 years postoperatively. The radiographic parameters hip-knee-ankle (HKA) angle, joint line convergence angle on standing radiographs (standing JLCA), and weightbearing line (WBL) ratio were assessed preoperatively and at 3 months, 6 months, 1 year, and 2 years postoperatively. To evaluate valgus laxity, we assessed the valgus JLCA and medial joint opening (MJO) at the aforementioned time points using valgus stress radiographs.

RESULTS

All clinical results at the 2-year follow-up were significantly improved compared with those obtained at the preoperative assessment (P < .001). The postoperative HKA angle significantly differed from the preoperative one, and no significant valgus progression was observed during follow-up (preoperative, 8.5°± 2.7°; 3 months, -3.5°± 2.0°; 6 months, -3.2°± 2.3°; 1 year, -3.1°± 2.3°; 2 years, -2.9°± 2.5°; P < .001) The mean WBL ratio was 62.5% ± 9.0% at 2 years postoperatively. The postoperative valgus JLCA at all follow-up points did not significantly change compared with the preoperative valgus JLCA (preoperative, -0.1°± 2.1°; 3 months, -0.2°± 2.4°; 6 months, -0.1°± 2.5°; 1 year, 0.1°± 2.5°; 2 years, 0.2°± 2.2°) The postoperative MJO at all follow-up points did not significantly change compared with the preoperative MJO (preoperative, 7.1 ± 1.7 mm; 3 months, 7.0 ± 1.7 mm; 6 months, 6.9 ± 1.9 mm; 1 year, 6.7 ± 1.8 mm; 2 years, 6.8 ± 1.8 mm).

CONCLUSION

Transection of the sMCL during MOWHTO does not increase valgus laxity and could yield desirable clinical and radiographic results.

Association of Serum Vitamin D with Serum Cytokine Profile in Patients with Knee Osteoarthritis

OBJECTIVE

The role of vitamin D in the pathogenesis of osteoarthritis (OA) is not well understood. In this study, we aimed to investigate the association of serum vitamin D with the serum cytokine profile in patients with primary knee OA.

DESIGN

In a cross-sectional study, 116 patients with radiologic diagnosis of grade I to III knee OA were included. The study population included 79 (75.9%) females and 25 (24.1%) males with a mean age of 55.1 ± 9.6 years. The serum concentration of IL-6, IL-8, TNF-α, IL-4, IL-10, IL-13, and vitamin D were assessed using an enzyme-linked immunosorbent assay. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used for the assessment of patient's reported disability associated with knee OA.

RESULTS

Serum vitamin D status was deficient, insufficient, and sufficient in 18 (15.5%), 63 (54.3%), 35 (30.2%) patients, respectively. Higher levels of serum IL-6 were observed in patients with vitamin D deficiency (P = 0.022). The mean serum vitamin D level was not associated with OA grade (P = 0.88) and WOMAC scores of the patients (P = 0.67). Serum IL-6 level was significantly associated with both OA grade and WOMAC scores of the patients (P < 0.001 and P = 0.001, respectively). The vitamin D status was not significantly associated with the serum levels of other evaluated cytokines.

CONCLUSION

Vitamin D deficiency in knee OA seems to be associated with a higher release of IL-6. Therefore, vitamin D supplementation could reduce the disease burden by controlling the IL-6 release.

Serum Calprotectin as a Blood-Based Biomarker for Monitoring Knee Osteoarthritis at Early but Not Late Stages

OBJECTIVE

The identification of early-stage osteoarthritis (OA) is crucial for the deceleration of its progression; however, no reliable biomarker is available for this purpose. The current study aimed to determine the role of serum calprotectin in the detection of early-stage knee OA.

DESIGN

In a case-control study, serum samples were collected from 84 patients with primary bilateral knee OA and 52 healthy controls. The radiographic grading of knee OA was performed using the Kellgren-Lawrence classification system. Serum concentrations of calprotectin were measured using an enzyme-linked immunosorbent assay.

RESULTS

The mean serum calprotectin level was 2908 ± 2516 ng/mL in OA patients and 901 ± 875 ng/mL in healthy control subjects (P < 0.001). Mean serum calprotectin levels were significantly higher in the lower stages of OA: 3740 ± 2728 ng/mL in OA grade I, 3100 ± 2084 ng/mL in OA grade II, 2246 ± 1418 ng/mL in OA grade III, and 2035 ± 765 ng/mL in OA grade IV (P = 0.047). Serum calprotectin levels were significantly higher in patients with a disease duration <42 months compared with those with a disease duration >42 months (P = 0.043).

CONCLUSION

Serum calprotectin level increases significantly in the early stages of OA and shows a reverse association with disease severity. Therefore, it could be suggested as a promising blood-based marker for early-stage knee OA.

Prior high tibial osteotomy is not a contraindication for medial unicompartmental knee arthroplasty

PURPOSE

To report on the outcome and complications of minimal invasive medial unicondylar knee arthroplasty (UKA) after failed prior high tibial osteotomy (HTO) as treatment for medial osteoarthritis in the knee. The hypothesis was that good results can be achieved, if no excessive postoperative valgus alignment and abnormal proximal tibial geometry is present.

METHODS

All medial UKAs after failed prior HTO (n = 30), performed between 2010 and 2018 were retrospectively reviewed. The patients were followed for revision surgery and survival of the UKA (defined as revision to TKA). Clinical examination using the Knee Society Score (KSS), Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as radiological examination was performed. Radiographs were studied and the influence of the demographic factors and the radiographic measurements on the survival and the clinical outcome was analysed.

RESULTS

After a follow-up of 4.3 ± 2.6 years (2.1-9.9) 27 UKAs were available. The survival rate was 93.0%. Two UKAs were revised to TKA (excessive valgus alignment and tibial loosening with femoropatellar degeneration). Two further patients had revision surgery (hematoma and lateral meniscus tear). Follow-up clinical and radiological examination was performed in 21 cases: KSS 82.9 ± 10.1 (54.0-100.0), KSS (function) 93.3 ± 9.7 (70.0-100.0); OKS 42.7 ± 6.0 (25.0-48.0); WOMAC 7.9 ± 15.6 (0.0-67.1). No significant influence of demographic factors or radiological measurements on the clinical outcome was present.

CONCLUSION

Prior HTO is not a contraindication for medial UKA, because good-to-excellent results can be achieved in selected patients with medial osteoarthritis and previous HTO, treated with medial UKA, in a midterm follow-up. Excessive mechanical valgus axis should be avoided; therefore, patient selection and accurate evaluation of medial laxity, preoperative mechanical axis, joint line convergence and proximal tibial geometry are important.

LEVEL OF EVIDENCE

III.

Classical target coronal alignment in high tibial osteotomy demonstrates validity in terms of knee kinematics and kinetics in a computer model

PURPOSE

The purpose of this study was to determine the ideal coronal alignment under dynamic conditions after open-wedge high tibial osteotomy (OWHTO). It was hypothesised that, although the classical target alignment was based on experimental evidence, it would demonstrate biomechanical validity.

METHODS

Musculoskeletal computer models were analysed with various degrees of coronal correction in OWHTO during gait and squat, specifically with the mechanical axis passing through points at 40%, 50%, 60%, 62.5%, 70%, and 80% of the tibial plateau from the medial edge, defined as the weight-bearing line percentage (WBL%). The peak load on the lateral tibiofemoral (TF) joint, the medial collateral ligament (MCL), and anterior cruciate ligament (ACL) tensions, and knee kinematics with or without increased posterior tibial slope (PTS) were evaluated.

RESULTS

The classical alignment with WBL62.5% achieved sufficient load on the lateral TF joint and maintained normal knee kinematics after OWHTO. However, over-correction with WBL80% caused an excessive lateral load and non-physiological kinematics. Increased WBL% resulted in increased MCL tension due to lateral femoral movement against the tibia. With WBL80%, abnormal contact between the medial femoral condyle and the medial intercondylar eminence of the tibia occurred at knee extension. The screw-home movement around knee extension and the TF rotational angle during flexion were reduced as WBL% increased. Increased PTS was associated with increased ACL tension and decreased TF rotation angle because of ligamentous imbalance.

CONCLUSIONS

The classical target alignment demonstrated validity in OWHTO, and over-correction should be avoided as it negatively impacts clinical outcome.

LEVEL OF EVIDENCE

IV.