Progression of joint arthrosis 10 to 15 years after high tibial osteotomy

Knee Osteotomy Decreases Joint Inflammation Based on Synovial Histology and Synovial Fluid Analysis

PURPOSE

To examine the biological changes in the joints of patients with knee osteoarthritis (OA) before and after around-knee osteotomy (AKO), focusing on synovial fluid (SF) and synovial pathological changes.

METHODS

Patients who underwent AKO for medial compartment knee OA between 2019 and 2021 were examined. SF and synovium were obtained at the time of AKO and plate removal after bone union (mean, 16.8 months [range: 11-38 months] postoperatively). SF volume and interleukin (IL)-6 concentrations in SF were assayed using enzyme-linked immunosorbent assay. Synovitis was assessed histologically using a semiquantitative scoring system. Macrophage infiltration was assessed by immunohistochemistry using a semiquantitative score for F4/80 expression. The M1/M2 ratio was calculated using percentage of cells positive for CD80 and CD163. The expression of proinflammatory cytokines was assessed by the percentage of IL-1β- and IL-6-positive cells. The number of vascular endothelial growth factor-positive luminal structures was counted to assess angiogenesis. The change in each parameter was compared before and after AKO using the Wilcoxon matched-pairs signed-rank test.

RESULTS

Twenty-four knees of 21 patients were included. SF volume and IL-6 concentration significantly decreased postoperatively (12.6 ± 2.1 mL vs 4.2 ± 0.6 mL; P < .0001 and 50.5 ± 8.6 pg/mL vs 20.7 ± 3.8 pg/mL; P = .0001, respectively). A significant reduction in synovitis score (P = .0001), macrophage infiltration (P < .0003), M1/M2 ratio (P < .0007), angiogenesis (P < .0001), and the percentage of IL-1β- and IL-6-positive cells in the intima (P < .008 and P < .002, respectively) was found after AKO.

CONCLUSIONS

SF volume and IL-6 concentrations in the SF decreased and inflammatory synovium pathology improved after AKO. In addition to biomechanical changes, the biological environment of the joint can be improved after AKO.

LEVEL OF EVIDENCE

Level IV, retrospective therapeutic case series.

Preoperative overweight and obesity do not cause inferior outcomes following open-wedge high tibial osteotomy: A retrospective cohort study of 123 patients

Open-wedge high tibial osteotomy (OWHTO) is effective in treating medial compartment osteoarthritis. The association between body mass index (BMI) and outcomes following OWHTO is being debated. This study compared radiographic and clinical outcomes between patients with preoperative overweight, obesity, and normal BMI following OWHTO for medial compartment osteoarthritis. In total, 123 patients (123 knees) who underwent OWHTO for medial compartment osteoarthritis were enrolled and were divided into normal-BMI (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (>30 kg/m2) groups based on body mass index. The numeric rating scale for pain, mechanical tibiofemoral angle (mTFA), tibia tilting angle (TTA), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for function were evaluated preoperatively and at postoperative follow-ups. The improvements of clinical and radiological outcomes in normal-BMI, overweight, and obese groups were not significantly different. The incidence of soft tissue irritation, wound infection, nonunion, and conversion to total knee arthroplasty were not significantly different between groups.The clinical and radiological outcomes in patients with preoperative overweight, obesity, and normal-BMI were not significantly different. Preoperative overweight and obesity thus has no effect on outcomes following OWHTO during the two years follow-up period. These findings cannot be generalized to patients with morbid obesity.

Long-term results of the subtubercle tibial osteotomy using the circular external fixator for medı̇al compartment osteoarthrı̇tı̇s of knee

BACKGROUND

We evaluated the long-term clinical and radiographic outcomes of patients who underwent subtubercular tibial osteotomy (STO) with Ilizarov external fixation used for high tibial osteotomy for medial knee osteoarthritis (MKOA).

METHODS

Between October 2003 and December 2011, 42 knees of 40 patients who had undergone STO with Ilizarov external fixator with a diagnosis of MKOA were evaluated. Survival analysis was performed by examining the duration of total knee arthroplasty (TKA). Clinical and radiological variables were collected at the time of admission after removal of the fixator and at outpatient follow up.

RESULTS

Mean age was 49.3 ± 5.68 (range 37-61) years, mean postoperative follow up time was 14.22 ± 2.93 (range 9-18) years, and mean fixator duration was 14.6 (range 13-20) weeks. Survival analysis showed 100% at 5 years, 95.2% at 10 years and 88.1% at 15 years. Clinical examination of the patients showed significant improvement in American Knee Society score (KSS), KSS functional score and Oxford Knee Score (OKS) score (P = 0.005). In the study, it was observed that the patients' knee osteoarthritis had progressed over time. On examination, radiographic measurements including mechanical axis deviation, medial proximal tibial angle, femorotibial angle, and joint line alignment angle improved significantly after deformity correction (P = 0.001).

CONCLUSION

STO using the Ilizarov method offers long-term survival. It provides effective treatment in young patients with isolated MKOA. Achieving the desired amount of correction in the coronal and sagittal planes can be presented as a surgical technique for the treatment of MKOA as an effective method in clinical and radiological correction.

Good long-term survival and patient-reported outcomes after high tibial osteotomy for medial compartment osteoarthritis

The lateral closing and medial opening wedge high tibial osteotomy can correct a varus malalignment of the knee caused by medial compartment osteoarthritis. These procedures have produced great short-term and mid-term results. As no systematic review has examined their long-term results yet, the goal of this article was to compare the results of all articles about lateral closing and medial opening wedge high tibial osteotomies, published after the year 2000, with a mean follow-up of more than 10 years. A systematic search of the Medline, Web of Science and Cochrane databases resulted in the inclusion of 30 articles. All these studies combined examined the results of 7087 high tibial osteotomies in a total of 6636 patients after a mean follow-up of more than 10 years. Primary outcome measures were the survival rate of the osteotomy, functional scores, patient satisfaction and pain scores. Secondary outcome measures were alignment correction and the identification of factors influencing the survival of the osteotomy. The 5-year, 10-year, 15-year and 20-year survival rates, respectively, ranged from 86 to 100%, 64-97.6%, 44-93.2% and 46-85.1%. The subjective scoring systems showed an improvement postoperatively that was maintained until final follow-up. The anatomical and mechanical tibiofemoral axis were, respectively, corrected to a mean of 7.3°-13.8° of valgus and 0.6°-4° of valgus. The results of the articles evaluating the influence of potential risk factors were contradictory. Despite the low quality of the available evidence, the lateral closing and medial opening wedge high tibial osteotomy seem to remain valid long-term treatment options for patients with painful varus malalignment caused by isolated medial compartment osteoarthritis of the knee. The available results indicate that the need for arthroplasty could be delayed for more than 15 years in the majority of patients. However, higher-quality studies are needed to confirm these findings. As a systematic review is assigned a level of evidence equivalent to the lowest level of evidence used from the analyzed manuscripts, the level of evidence of this systematic review is IV.

Long-term survival rate of closing wedge high tibial osteotomy with high valgus correction: a 15-year follow-up study

PURPOSE

The influence of closing wedge high tibial osteotomy (CW-HTO) with high valgus correction on its survival is unclear. This study aimed to conduct a 15-year follow-up cohort study to estimate the long-term survival rate of CW-HTO. Factors related to poor outcomes were investigated.

METHODS

A total of 159 knees in 123 patients were followed up, and 120 knees in 96 patients were enrolled for statistical analysis. Femorotibial angles were measured by standing anterior-posterior radiographs of the knee. Clinical objective evaluation was performed by the Japanese orthopaedic association (JOA) score of the knee, and scores lower than 70 points defined the poor result (PR) group. The survival rate of OW-HTO was estimated. Logistic regression analyses were performed to determine the risk factors for PR and conversion to total knee arthroplasty (TKA).

RESULTS

A total of 16 knees in 15 patients (13.3%) underwent TKA 14.0 ± 4.8 (4-20) years after CW-HTO. The 5-year survival rate was 99.2%, 10-year was 96.7%, 15-year was 92.5%, and 86.7% at final follow-up (17.9 years). Based on the JOA score, 44 patients (35.8%) belonged to the PR group, and their risk factors were obesity (p = 0.018), low femorotibial angle (p = 0.019), low JOA score (p = 0.040), low knee extension angle (p = 0.045), and low knee flexion angle (p = 0.046).

CONCLUSIONS

The 15-year survival rate of CW-HTO was 92.5%. While higher scores of objective outcomes were kept over long-term follow-up, the risk factors for a worsening score or TKA conversion were obesity and severity of preoperative knee symptoms.

Role of high tibial osteotomy in medial compartment osteoarthritis of the knee: Indications, surgical technique and outcomes

Knee osteoarthritis (OA) is the most common joint disorder worldwide. In particular, primary knee OA often presents with a varus malalignment. This increases the loads going through the medial compartment resulting in cartilage degeneration and symptomatic arthritis. High tibial osteotomy (HTO) is the workhorse surgical procedure for treating medial knee OA. When performed precisely in the hands of an experienced surgeon, HTO can delay or avoid knee arthroplasty. Of note, outcomes of knee arthroplasty are at best unpredictable in patients of younger age. Hence, there is a growing need for joint preservation procedures for younger patients presenting with knee OA, of which HTO is one. Through this article, the authors of whom all are joint preservation surgeons with a special interest in osteotomy hope to share from their experience as well as the available literature on the indications, perioperative planning, surgical technique, outcomes as well as pearls and pitfalls of HTO.

Focal cartilage defects of the lateral compartment do influence the outcome after high tibial valgus osteotomy

INTRODUCTION

High tibial medial open-wedge valgus osteotomy (HTO) is a well-established procedure for unicompartimental medial osteoarthritis of the young and active patient. However, the influence of cartilage defects of the lateral compartment on the total outcome remains obscure.

METHODS

From 2005 to 2012, a total of 63 patients underwent HTO for medial osteoarthritis of the knee at a single university orthopaedic center. Baseline data as well as intraoperative findings, including the grade and location of cartilage lesions, were evaluated retrospectively. Two groups were formed regarding the integrity of the lateral tibiofemoral compartment as measured by the Outerbridge score (group A: no lateral cartilage defects, group B: mild to moderate lateral cartilage defects). Functional outcome was assessed using the Knee and Osteoarthritis Outcome Score (KOOS), including its five subscores.

RESULTS

Comparing pre- and postoperative data, we identified an overall benefit of the HTO procedure as measured by the KOOS. Group A (no lateral cartilage defects) showed an increase in all five KOOS subscores (p = 0.00-0.01), whereas for group B (mild to moderate lateral cartilage defects), only two KOOS subscores revealed a significant increase (p = 0.03-0.04). There was also a statistically significant difference in the total KOOS score with higher values for group A at the postoperative visit. Cartilage defects with a higher Outerbridge score were associated with lower postoperative KOOS subscores.

DISCUSSION

Mild to moderate cartilage defects of the lateral compartment humble the total outcome after HTO procedure. Thus, indication for HTO should be made very carefully if any degree of lateral cartilage degeneration is present.

Patellofemoral Chondromalacia Does Not Influence Radiographic and Clinical Outcomes following High Tibial Osteotomy

Effect of patellofemoral (PF) chondromalacia on results of high tibial osteotomy (HTO) has not been identified. Therefore, the objective of the present study was to analyze the effect of PF chondromalacia on relatively short-term radiographic and clinical outcomes of HTO. Patients who underwent open wedge HTO (OWHTO) from February 2010 to January 2015 were enrolled. A total of 101 knees were divided into two groups: 56 knees without PF chondromalacia in group A, while 45 knees with PF chondromalacia extended to subchondral bone in group B. Radiologic outcomes were compared using mechanical tibiofemoral angle, ratio of weight-bearing line (WBL), and minimal joint space width of the lateral compartment. Clinical outcomes were compared using range of motion in affected knee, visual analog scale, modified Lysholm score, and Kujala score. The mean mechanical tibiofemoral angle was 4.6 degree in group A and 4.8 degree in group B. The mean ratio of WBL was 63.8% in group A and 63.6% in group B at final. The mean minimum joint space width of the lateral compartment was 5.8 mm in group A and 5.8 mm in group B on standing AP radiograph. It was 5.3 mm in group A and 5.4 mm in group B on Rosenburg view at final. The mean ROM was 137.2 degree in group A and 137.5 degree in group B. The mean visual analog scale was 2.1 in group A and 2.3 in group B at final. The mean modified Lysholm score was 90.6 in group A and 89.1 in group B at final. The mean Kujala score was 90.2 in group A and 89.1 in group B at final. PF chondromalacia does not influence short-term radiographic and clinical outcomes following OWHTO.

Return to Sports After High Tibial Osteotomy Using the Opening Wedge Technique

Objective  The present paper evaluates the resuming of physical activities by young, active patients who practiced some sport modality and underwent a high tibial osteotomy (HTO) using the opening wedge technique. Methods  A total of 12 patients submitted to HTO using the opening wedge technique were prospectively analyzed. All patients were not playing sports at that time. Pre- and postoperative Lysholm and International Knee Documentation Committee (IKDC) scores, visual analog scale for pain and performance level were compared. The average follow-up time was of 12 months. Results  One patient resumed sporting activities at a performance level significantly lower compared to the preoperative level, while eight patients returned at a slightly below level, two returned at the same level and one patient returned at a higher level in comparison with the preoperative period. Conclusion  For isolated medial osteoarthrosis treatment, HTO using the opening wedge technique has favorable clinical and functional results, allowing patients to resume their sporting activities.

Changes in Coronal Alignment of the Knee Joint after Supramalleolar Osteotomy

BACKGROUND

Assessing knee joint orientation changes after SMO may help clinical advancement in managing patients with ipsilateral ankle and knee joint arthritis. However, knee joint changes after supramalleolar osteotomy (SMO) have not been reported. We investigated changes in coronal alignment of the knee joint after SMO.

METHODS

In this multicentre study, from January 2014 to December 2018, 47 ankles with varus osteoarthritis treated with SMO were retrospectively identified. Ankle joint changes were assessed using the tibiotalar angle, talar tilt angle, and lateral distal tibial angle (LDTA); knee joint changes using the medial proximal tibial angle (MPTA), medial and lateral joint space widths (mJSW and lJSW, respectively), and medial and lateral joint line convergence angles (JLCA); and lower limb alignment changes using mechanical axis deviation angle (MADA) and the hip-knee-ankle (HKA) angle measured on full-length anteroposterior radiographs of the lower extremity. Correlation analysis and binary logistic regression analysis were performed.

RESULTS

Postoperatively, LDTA (p < 0.001) and tibiotalar angle (p < 0.001) significantly changed, indicating meaningful improvement in the ankle joint varus deformity. Regarding the knee joint changes, JLCA significantly changed into valgus direction (p = 0.044). As for lower limb alignment changes, MADA significantly decreased (p < 0.001), whereas the HKA angle significantly increased (p < 0.001). In univariate and multivariate logistic regression analyses, changes in the MADA (p < 0.001) and the HKA angle (p < 0.001) were significantly correlated with the correction angle.

CONCLUSIONS

SMO remarkably improves ankle joint varus deformity, followed by significant lower limb alignment changes. Despite meaningful changes in JLCA, the relationship between the amount of osteotomy near the ankle joint and improvement in knee joint radiographic parameters was not significant. Radiographic parameters of the knee joint would less likely be changed following SMO.

Closing-wedge high tibial osteotomy, a reliable procedure for osteoarthritic varus knee

PURPOSE

The purpose of this study was to analyze the long-term clinical and radiological outcomes of patients who underwent closing-wedge High Tibial Osteotomy (HTO) for the treatment of medial compartment osteoarthritis and to evaluate the conversion rate to knee arthroplasty.

METHODS

A retrospective, non-randomized, monocentric study was performed in our Institution considering 166 patients between 1989 and 2012. The final population was composed by 82 patients (94 knees), median age at time of operation was 53 (range 45-73) years. All patients were evaluated clinically (HSS Score, Tegner Scale, VAS and Crosby-Insall Grading) and radiographically (osteoarthritis staging, hip-knee-ankle (HKA) angle, tibial slope and metaphyseal varus).

RESULTS

Mean follow-up was 11.9 ± 7.2 years. HSS Score increased significantly from 70.8 ± 10 to 93.2 ± 9.1 (p < 0.05) instead Tegner Scale increased from 1.3 ± 0 (range 1-4) to 2.8 ± 0.7 (range 2-6) at the last control (n.s.); VAS score significantly decreased from 7.9 ± 1.4 to 1.6 ± 1.1 (p < 0.05) at last follow-up. According to the Crosby-Insall Grading System, 80 patients (97.4%) reported excellent-good results. HKA angle decreased from 6.9° ± 3.5 to 2.6° ± 2.6 (p < 0.01), tibial slope decreased from 10.1° ± 1.4 to 6.8° ± 2.1 (p < 0.05) and finally the metaphyseal varus decreased from 4.2° ± 0 to 2.1° ± 1.2 (n.s.) at the last follow-up. Adverse events were reported in 4.8%. Osteotomy survivorship rate resulted 92% at 10 years, 82% at 15 years and 80% at 20 years. Sixteen revisions (9.6%) were reported at a mean period of 12.8 years.

CONCLUSIONS

CW-HTO is a valid option for medial osteoarthritis treatment, with successful results in both clinical and radiological outcomes.

LEVEL OF EVIDENCE

IV.

Factors Associated With Patient Satisfaction After Opening-Wedge High Tibial Osteotomy

Background:

Opening-wedge high tibial osteotomy (OWHTO) is expected to result in higher patient satisfaction compared with knee arthroplasty due to joint preservation. However, patient satisfaction rates as well as factors associated with satisfaction after OWHTO remain unclear.

Purpose:

To evaluate patient subjective satisfaction after OWHTO and determine factors associated with patient satisfaction after OWHTO.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

This study enrolled 123 patients (123 knees) who underwent unilateral OWHTO. Clinical parameters, including range of motion (ROM), visual analog scale (VAS) score for pain, Knee injury and Osteoarthritis Outcome Score (KOOS), weightbearing line ratio (WBLR), and medial proximal tibial angle (MPTA), were assessed before surgery and at the final follow-up at a minimum of 2 years. Patient satisfaction was evaluated using a 5-point scale regarding (1) surgery, (2) pain relief, (3) knee mobility, (4) daily living function, and (5) lower extremity alignment. The mean overall satisfaction scores for the 5 questions were calculated, and the sample was divided into 2 main groups (satisfied or unsatisfied). Preoperative characteristics, physical activity level, patient expectations for surgery, ROM, and KOOS were compared between the groups. Cartilage regeneration was assessed at the time of plate removal, and WBLR and MPTA were also assessed. Factors associated with patient satisfaction were analyzed using multivariable logistic regression analysis.

Results:

The mean ± SD follow-up was 54.6 ± 20.6 months. The mean WBLR significantly changed from 20.7% ± 11.8% preoperatively to 66.9% ± 10.2% at the final follow-up, and all KOOS subscale scores significantly improved after surgery. Of the 123 patients, 109 (88.6%) were graded as satisfied. Factors associated with patient satisfaction were expectations met (odds ratio, 17.4; P = .026), better postoperative KOOS Pain score (odds ratio, 1.30; P = .001), and better postoperative KOOS Activities of Daily Living score (odds ratio, 1.36; P = .002).

Conclusion:

OWHTO is an effective treatment in terms of subjective satisfactory outcomes. Patient expectations for surgery have a significant effect on patient satisfaction. Surgeons should consider patient expectations before OWHTO and provide patient education to improve patient satisfaction.

Patient-specific prediction of joint line convergence angle after high tibial osteotomy using a whole-leg radiograph standing on lateral-wedge insole

PURPOSE

To assess the usefulness of a whole-leg radiograph standing on lateral-wedge insole (LWI) for predicting the change in joint line convergence angle (JLCA) before vs. after high tibial osteotomy (HTO).

METHODS

Forty knees with medial osteoarthritis underwent open-wedge HTO. Pre-operatively, all patients had whole-leg radiographs taken in three different conditions: supine, standing, and standing on LWI inclined at 20°. A standing whole-leg radiograph was also obtained post-operatively. Radiological measurements including JLCA and percentage of mechanical axis (%MA) were compared. Using pre-operative radiographs, correction angles were calculated with the target %MA at 62.5%. Correlations between the difference in calculated correction angle among the three pre-operative conditions and the change in JLCA before vs. after HTO were assessed.

RESULTS

In the pre-operative standing conditions, the mean JLCA of 3.8° was significantly decreased to 3.2° using LWI, which did not differ from post-operative JLCA of 3.1°. Mean %MA significantly shifted laterally from 20.6 to 24.8% using LWI, and was strongly correlated with the change in JLCA (coefficient, 0.83). Calculated correction angles differed significantly among the three pre-operative conditions. The difference in calculated correction angle between standing with and without LWI was strongly correlated to the change in standing JLCA before vs. after HTO (coefficient, 0.73).

CONCLUSION

Larger differences in calculated correction angles between pre-operative radiographs standing with and without LWI predicted larger changes in JLCA after HTO. Whole-leg radiograph standing on LWI is a promising modality for correct pre-operative planning considering patient-specific changes in JLCA before vs. after HTO.

LEVEL OF EVIDENCE

IV.

Gait analysis following medial opening-wedge high tibial osteotomy

PURPOSE

High tibial osteotomy (HTO) is used to treat young and active patients with knee osteoarthritis (OA) and varus deformity. The medial compartment OA alters the patients' gait.

METHODS

A prospective study was carried out in 21 consecutive patients operated for HTO due to knee OA with varus deformity. There were 14 men and 7 women, with a median age of 51.9 years (38-64). Their gait was analyzed preoperatively and at 1 year postoperatively, and compared to a healthy control group. Clinical assessment (KOOS, WOMAC, Lysholm, and SF-36 scores) was also performed preoperatively and postoperatively.

RESULTS

Patients with medial compartment OA had altered gait relative to the control population. Their walking speed was slower, step length was shorter, and single-leg stance time was shorter, while the double-leg stance time was longer (P < 0.001). Step width was not different between the two groups preoperatively (n.s.), but it was wider in the patient group postoperatively (P = 0.003). There were no differences in the patients' gait parameters before and after the osteotomy (n.s.). However, there was an improved perception of walking so that it is no longer different from controls (n.s.). The KOOS, WOMAC, Lysholm and SF-36 scores improved after HTO. The preoperative median of 7° varus (1-11) was corrected to 3° valgus (0-6).

CONCLUSION

Medial compartment OA with varus deformity leads to gait modifications. HTO does not alter the time-distance parameters of gait; however, patients have improved perception of their walking ability. HTO leads to excellent results for knee function, and improves quality of life without modifying the gait pattern.

LEVEL OF EVIDENCE

II.

What Determines the Success of Closed-Wedge High Tibial Osteotomy: Severity of Malalignment, Obesity, Follow-up Period, or Age?

Objectives:

High tibial osteotomy (HTO) is a well-established procedure for the treatment of medial knee osteoarthritis originating from malalignment of the lower extremity. The current study was designed to evaluate the clinical and radiographic results of closed-wedge HTO for the treatment of medial knee osteoarthritis and to reveal factors affecting the outcome.

Methods:

A retrospective study was conducted with 138 patients who were operated on for medial knee osteoarthritis between 2000 and 2007 using closed-wedge HTO. Preoperative and follow-up physical examination findings, body mass index (BMI) values, and Hospital for Special Surgery (HSS) and Lysholm knee scores were reviewed. Radiographic evaluation included measurement of the mechanical axis preoperatively and the most recent follow-up orthoroentgenograms. The follow-up knee scores were evaluated according to preoperative mechanical axis, obesity, age, follow-up period, and gender of the patient. The mechanical axis measurement was assessed based on obesity, age, and follow-up period.

Results:

The mean preoperative and latest follow-up mechanical axis was 4.92^o±4.24^o varus and 3.43^o±3.74^o valgus, respectively (p=0.0001). Improvement in the Lysholm (p=0.0001) and HSS (p=0.0001) knee scores was significant. The preoperative mechanical axis, obesity, follow-up period, and gender had no negative effect on the follow-up knee scores, whereas a preoperative age over 50 years had a negative effect on the follow-up knee score. Obesity and the length of the postoperative follow-up period did not have a negative effect on the postoperative mechanical axis, whereas a preoperative age over 50 had a negative effect on the postoperative mechanical axis.

Conclusion:

The results of this study suggest that medial knee osteoarthritis may be treated successfully with closed-wedge HTO. The analysis indicated that factors such as obesity, the degree of preoperative deformity, and gender do not adversely affect the success of treatment. However, a preoperative age over 50 adversely affected the outcome.

A preliminary modeling investigation into the safe correction zone for high tibial osteotomy

BACKGROUND

High tibial osteotomy (HTO) re-aligns the weight-bearing axis (WBA) of the lower limb. The surgery reduces medial load (reducing pain and slowing progression of cartilage damage) while avoiding overloading the lateral compartment. The optimal correction has not been established. This study investigated how different WBA re-alignments affected load distribution in the knee, to consider the optimal post-surgery re-alignment.

METHODS

We collected motion analysis and seven Tesla MRI data from three healthy subjects, and combined this data to create sets of subject-specific finite element models (total=45 models). Each set of models simulated a range of potential post-HTO knee re-alignments. We shifted the WBA from its native alignment to between 40% and 80% medial-lateral tibial width (corresponding to 2.8°-3.1° varus and 8.5°-9.3° valgus), in three percent increments. We then compared stress/pressure distributions in the models.

RESULTS

Correcting the WBA to 50% tibial width (0° varus-valgus) approximately halved medial compartment stresses, with minimal changes to lateral stress levels, but provided little margin for error in undercorrection. Correcting the WBA to a more commonly-used 62%-65% tibial width (3.4°-4.6° valgus) further reduced medial stresses but introduced the danger of damaging lateral compartment tissues. To balance optimal loading environment with that of the historical risk of under-correction, we propose a new target: WBA correction to 55% tibial width (1.7°-1.9° valgus), which anatomically represented the apex of the lateral tibial spine.

CONCLUSIONS

Finite element models can successfully simulate a variety of HTO re-alignments. Correcting the WBA to 55% tibial width (1.7°-1.9° valgus) optimally distributes medial and lateral stresses/pressures.

Changes in coronal alignment of the ankle joint after high tibial osteotomy

PURPOSE

The purpose of this study was to investigate changes in coronal alignment of the ankle joint after HTO. Our hypothesis was that ankle joint orientation may become more parallel or less parallel to the ground after HTO, and this change may affect ankle symptoms.

METHODS

Eighty-six knees were retrospectively analysed after HTO for varus osteoarthritis. Preoperative and follow-up whole-leg radiographs were taken. The hip-knee-ankle (HKA) angle and medial proximal tibial angle (MPTA) were measured to evaluate coronal alignment of the knee. Tibial plafond inclination (TPI), talar inclination (TI), talar tilt (TT), and lateral distal tibial angle (LDTA) were measured to evaluate coronal alignment of the ankle. Patients were divided into two groups: those who exhibited a decrease in the absolute value of TPI and TI after HTO (group A) and those who exhibited an increase in the absolute value of TPI or TI after HTO (group B). Clinical outcomes of the knee and ankle were evaluated pre- and postoperatively.

RESULTS

Mean TPI and TI changed from 6.9° ± 3.6° and 8.0° ± 3.8° to 2.8° ± 3.1° and 3.9° ± 3.0° in group A (P < 0.001 for both) and from -1.3° ± 3.7° and 0.6° ± 4.5° to -6.0° ± 4.2° and -4.6° ± 5.9° in group B (P = 0.018 for both). VAS for ankle pain did not change significantly after HTO (n.s.) in group A, whereas those of group B increased significantly after HTO (P = 0.014).

CONCLUSION

Ankle joint orientation becomes more parallel or less parallel to the ground after HTO. Smaller preoperative HKA and LDTA result in a more valgus ankle joint orientation after HTO. Ankle symptoms were affected by coronal alignment changes of the ankle after HTO.

LEVEL OF EVIDENCE

III.

High tibial osteotomy in varus knees: indications and limits

Opening wedge high tibial osteotomy (OWHTO) is a surgical procedure that aims to correct the weight-bearing axis of the knee, moving the loads laterally from the medial compartment. Conventional indications for OWHTO are medial compartment osteoarthritis and varus malalignment of the knee; recently OWHTO has been used successfully in the treatment of double and triple varus. OWHTO, in contrast to closing wedge high tibial osteotomy, does not require fibular osteotomy or peroneal nerve dissection, or lead to disruption of the proximal tibiofibular joint and bone stock loss. For these reasons, interest in this procedure has grown in recent years. The aim of this study is to review the literature on OWHTO, considering indications and prognostic factors (body mass index, grade of osteoarthritis, instability, range of movement and age), outcomes at mid-term follow-up, and limits of the procedure (slope modifications, patellar height changes and difficulties in conversion to a total knee arthroplasty).

High Tibial Osteotomy for Medial Compartment Osteoarthritis: A Comparison of Clinical and Radiological Results from Closed Wedge and Focal Dome Osteotomies

This study aimed to evaluate the clinical and radiological results of closed wedge osteotomy (11 knees) and focal dome osteotomy (14 knees) in cases of high tibial osteotomy undertaken for varus knee with medial compartment osteoarthritis. Clinical evaluation was performed using the Knee Society Score and no significant difference was seen between the two groups at final follow-up. Radiological evaluation was made on the basis of the pre- and postoperative mechanical axis, postoperative movement of the tibial axis, loss of correction at final follow-up and patellar height measured using the Insall-Salvati index. Statistically significant differences were seen with focal dome osteotomy compared with closed wedge osteotomy in the Insall-Salvati index at final follow-up, the amount of correction loss and the change in tibial axis location. It is concluded that, in the treatment of medial compartment osteoarthritis by high tibial osteotomy, focal dome osteotomy is more beneficial than closed wedge osteotomy in not creating any additional deformity.

Biomechanical Study of the Fixation Plates For Opening Wedge High Tibial Osteotomy

Purpose

The purpose of this study was to compare the mechanical stability of three types of plate systems for opening wedge high tibial osteotomy.

Materials and Methods

Forty-eight fresh frozen porcine tibia specimens were assigned to three different fixation device groups: Aescular group (16 specimens) was fixed with Aescular plates; Puddu group (16 specimens) with a Puddu plate, and TomoFix group (16 specimens) with a TomoFix plate. We compared axial displacements under compression loads from 200 to 2,000 N and maximal loads at failure among 8 specimens per group. We also compared displacements under cyclic load after 100 cycles at a compressive load of 2,000 N among 8 specimens per group.

Results

In all three groups, displacement under compression load increased with the increase in the axial compressive load; however, no significant intergroup differences were observed in the mean values under tested loading conditions. The mean maximal loads at failure were not significantly different (6,055, 6,798, and 6,973 N in the Aescular, Puddu, and TomoFix groups, respectively; p=0.41). While the TomoFix group showed less extension and strain during the cyclic load test, the mean values showed no significant differences among groups.

Conclusions

All three plate systems were found to provide fixation stability suitable for bearing axial compression and cyclic loads while walking.

Survival and clinical outcome of isolated high tibial osteotomy and combined biological knee reconstruction

PURPOSE

We sought to determine survival and clinical outcomes of high tibial osteotomy (HTO) with or without articular cartilage surgery and/or meniscal allograft transplantation in patients with medial compartment chondral pathology, varus malalignment, and/or meniscal deficiency, whether there is any difference in survival or clinical outcome between these patient cohorts, and whether there is any difference between opening- (OWHTO) and closing-wedge (CWHTO) techniques.

METHODS

A systematic review of multiple medical databases was performed using PRISMA guidelines. Study quality was assessed via modified Coleman Methodology Scores (MCMS).

RESULTS

Sixty-nine studies were included (4557 subjects). MCMS rating was overall poor. Mean follow-up was 7.1 years. Mean subject age was 53 years. Survival of isolated HTO was 92.4%, 84.5%, 77.3%, and 72.3% at 5, 10, 15, and 20 years of follow-up. At 5 years of follow-up, HTO with articular cartilage surgery had significantly greater survival (97.7%) than either isolated HTO (92.4%) or HTO with MAT (90.9%). Isolated HTO, HTO with articular cartilage surgery, and HTO with MAT all significantly improved subjective and objective clinical outcome scores. At two years of follow-up, survival was significantly greater following OWHTO (98.7%) versus CWHTO (96.7%). However, at all other time points with or without combined articular cartilage surgery and/or MAT, there was no significant survival difference between the techniques.

CONCLUSIONS

Survival and clinical outcomes of isolated HTO were excellent at short- and mid-term follow-ups, but deteriorated with time. HTO with concomitant procedures also demonstrated excellent early survival and clinical outcomes that deteriorated with time (up to 10 years).

Boomerang proximal tibial osteotomy for the treatment of severe varus gonarthrosis

PURPOSE

The purpose of the study was to review the results of modified infratubercle displacement osteotomy in patients with severe varus gonarthrosis and to determine the factors influencing outcomes.

METHODS

A total of 177 knees in 133 patients with severe varus gonarthrosis were treated with infratubercle boomerang-shaped osteotomy, stabilised with dual plates. The mean age of the patients was 63.8 years (range 43-80 years), and the mean follow-up period was 61.4 months (range 24 -139 months). The factors associated with clinical and survival outcomes were analysed including age, gender, body mass index (BMI), preoperative and post-operative femorotibial angle and femorotibial angle at one year after surgery.

RESULTS

Using the Knee Society clinical rating system 149 knees or 84.2 % were rated as having good to excellent results and 21 knees or 15.8 % as having fair to poor results. Overall, the mean preoperative knee score of 33.6 points had improved significantly to 80.7 points at the final follow-up (p < 0.001). Using Kaplan-Meier survivorship analysis the five-year survival was 97.1 % with conversion to arthroplasty or second osteotomy as the end point and 89.2 % with a knee score of under 70 points as the end point. The anatomical femorotibial angle at one year after osteotomy had the most significant positive effect on the clinical (p < 0.001) and survival outcomes for all end points (p = 0.002 for conversion to arthroplasty or second osteotomy and p < 0.001 for knee score less than 70 points).

CONCLUSIONS

The boomerang osteotomy can create adequate valgus alignment in severe varus gonarthrosis. The one-year post-operative knee alignment of 11° valgus provided the most satisfactory results and that between six and 15° valgus the longest survival time.

The impact of a high tibial valgus osteotomy and unicondylar medial arthroplasty on the treatment for knee osteoarthritis: a meta-analysis

PURPOSE

Both high tibial valgus osteotomy (HTO) and unicompartmental medial knee arthroplasty (UKA) are established methods for the treatment for moderate stages of OA. This is the first global meta-analysis to compare the long-term effects of both methods regarding survival, outcomes and complications of total arthroplasty.

METHODS

Literature research was performed using established medical databases: MEDLINE (via PubMed), EMBASE (via OVID) and the Cochrane register. Criteria for inclusion were as follows: English or German papers, a clinical trial with a clear description of survival, an outcome evaluation using a well-described knee score and a follow-up >5 years. Statistical analysis was performed using the special meta-analysis software called "Comprehensive Meta Analysis" (version 2.0; Biostat, Englewood, NJ, USA).

RESULTS

Final meta-analysis after the full-text review included 46 studies about valgus HTO and 43 studies about medial UKA. There were no significant differences between valgus HTO and medial UKA in terms of the number of total required replacements. After a 5- to 8-year follow-up, 91.0% of the valgus HTO patients and 91.5% of medial UKA patients did not need a total replacement. This value was 84.4% for valgus HTOs and 86.9% for medial UKAs after a 9- to 12-year follow-up. Mean survival time to TKA was 9.7 years after valgus HTO and 9.2 years after medial UKA. Clinical outcome was significantly better after medial UKA in a 5- to 12-year follow-up. After more than 12 years, results were comparable in both groups. No significant differences were seen in the complication rates.

CONCLUSIONS

This meta-analysis aimed to find the advantages and disadvantages of two established methods for the treatment for medial compartment knee osteoarthritis. Valgus HTO is more appropriate for younger patients who accept a slight decrease in their physical activity. Medial UKA is appropriate for older patients obtaining sufficient pain relief but with reduced physical activity.

LEVEL OF EVIDENCE

II.

Osteotomy around the knee: evolution, principles and results

PURPOSE

This article summarises the history and evolution of osteotomy around the knee, examining the changes in principles, operative technique and results over three distinct periods: Historical (pre 1940), Modern Early Years (1940-2000) and Modern Later Years (2000-Present). We aim to place the technique in historical context and to demonstrate its evolution into a validated procedure with beneficial outcomes whose use can be justified for specific indications.

MATERIALS AND METHODS

A thorough literature review was performed to identify the important steps in the development of osteotomy around the knee.

RESULTS

The indications and surgical technique for knee osteotomy have never been standardised, and historically, the results were unpredictable and at times poor. These factors, combined with the success of knee arthroplasty from the 1980s onward, led to knee osteotomy being regarded as an irrelevant surgical option by many surgeons. Despite its fluctuating reputation, this article demonstrates the reasons for the enduring practice of osteotomy, not least because achieving the appropriate alignment is now recognised as the foundation step when planning any surgical intervention.

CONCLUSIONS

With appropriate patient selection, accurate pre-operative planning, modern surgical fixation techniques and rapid rehabilitation, osteotomy around the knee is now an effective biological treatment for degenerative disease, deformity, knee instability and also as an adjunct to other complex joint surface and meniscal cartilage surgery.

LEVEL OF EVIDENCE

V.

Can patients really participate in sport after high tibial osteotomy?

PURPOSE

The possibility to return to sporting activity can be an important consideration in the decision-making process in femorotibial osteoarthritis. We analyzed functional outcomes and sport participation in a continuous series of HTO and asked whether this procedure could match expectations in active and motivated patients.

METHODS

We retrospectively investigated activities, sports participation, and the level of satisfaction in 139 patients with unilateral noncomplicated HTO. The study included 41 women and 98 men with a mean age of 59 years and a mean 50 months of follow-up.

RESULTS

Eighty-seven patients (63%) reported that their knee was "normal," and eighty-six patients (62%) felt that their activities were limited by their knee. A total of 78 patients (56%) reported that they were as active as they expected to be before the intervention. Of these patients, 98% were satisfied. Of the patients who were not as active as they thought they would be, 51% were satisfied (P < 0.0001). The duration of preoperative pain, the age at evaluation, and the number of previous surgeries did not influence the subjective result. Among patients under 75 years, 28% regularly participated in strenuous sports, but 40% were motivated for these activities. 66% of the motivated patients regularly participated in at least one impact sport.

CONCLUSION

This study shows that young motivated patients are able to resume strenuous activities following HTO. However, patients must be informed that they will typically not recover their pre-pathology level and that residual pain during strenuous sports is not exceptional.

LEVEL OF EVIDENCE

Therapeutic study, Level IV.

High tibial osteotomy in medial compartment osteoarthritis and varus deformity using the Taylor spatial frame: early results

We report the early results of high tibial osteotomy (HTO) in medial compartment osteoarthritis (OA) and varus deformity using the Taylor spatial frame (TSF). Between October 2005 and April 2007, 9 patients with medial compartment OA and varus deformity underwent TSF application and medial opening wedge HTO. Pre- and post-operative Oxford knee scores, SF-12 and visual analogue pain scores were recorded along with radiographic outcomes. Median follow-up was 19 months (range 15–35). Mean age at operation was 49 years (range 37–59). The median time spent in the frame was 18 weeks (range 12–37). The mean preoperative Oxford knee score was 28.7. This improved to a mean of 35.4 post-operatively (P = 0.0142). 6 (67%) patients had a documented pin-site infection. With TKR as an end point, the survival rate of HTOs was 88.9% at a median of 19 months follow-up. This study demonstrates that in selected patients the TSF provides a viable treatment option for performing HTO in medial compartment OA with varus deformity.

Effect of tibial tuberosity advancement on the contact mechanics and the alignment of the patellofemoral and femorotibial joints

OBJECTIVE

To evaluate the effect of tibial tuberosity advancement (TTA) on patellofemoral (PF) contact mechanics, and alignment of the PF and femorotibial (FT) joints in cranial cruciate ligament (CrCL)-deficient stifles of dogs.

STUDY DESIGN

Ex vivo biomechanical study.

ANIMALS

Unpaired cadaveric hind limbs (n=9).

METHODS

Digital pressure sensors placed in the PF joint were used to measure contact force, contact area, peak and mean contact pressure, and peak pressure location with the limb under an axial load of 30% body weight and a stifle angle of 135°. The FT and PF poses were obtained using a 2-dimensional computer digitization technique. Each specimen was tested under normal, CrCL-deficient, and TTA-treated conditions. Data was normalized and analyzed, after testing for normality by Wilk-Shapiro, using 1 sample T-test, paired T-test, and ANOVA; P≤.05 was considered significant. Bonferroni's correction was used when needed.

RESULTS

A significant cranioproximal tibial displacement and increase in patellar tilt were found in the CrCL-deficient joints. Both FT and PF alignments were restored after TTA. Contact areas and peak pressure did not vary between conditions. Peak pressure location displaced proximally from intact to CrCL-deficient condition and returned to normal after TTA. Total force measured in the CrCL-deficient stifle and TTA conditions were significantly lower than in the control.

CONCLUSION

TTA restored the normal FT and PF alignment, and reduced the retropatellar force by about 20%.

Long-term survival of high tibial osteotomy for medial compartment osteoarthritis of the knee

BACKGROUND

The management of degenerative arthritis of the knee in the younger, active patient presents a challenge to the orthopaedic surgeon. Surgical treatment options include high tibial osteotomy (HTO), unicompartmental knee arthroplasty, and total knee arthroplasty.

PURPOSE

To examine the long-term survival of closing wedge HTO in a large series of patients up to 19 years after surgery.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Four hundred fifty-five consecutive patients underwent lateral closing wedge HTO for medial compartment osteoarthritis between 1990 and 2001. Between 2008 and 2009, patients were contacted via telephone, and assessment included incidence of further surgery, current body mass index (BMI), Oxford Knee Score, and British Orthopaedic Association Patient Satisfaction Scale. Failure was defined as the need for revision HTO or conversion to unicompartmental knee arthroplasty or total knee arthroplasty. Survival analysis was completed using the Kaplan-Meier method.

RESULTS

High tibial osteotomy survival was determined in 413 patients (91%). Of the 397 remaining living patients at the time of final review, 394 (99%) were contacted for follow-up via telephone interview. The probability of survival for HTO at 5, 10, and 15 years was 95%, 79%, and 56%, respectively. Multivariate regression analysis showed that age under 50 years (P = .001), BMI less than 25 (P = .006), and ACL deficiency (P = .03) were associated with better odds of survival. Mean Oxford Knee Score was 40 of 48 (range, 17-48). Overall, 85% of patients were enthusiastic or satisfied, and 84% would undergo HTO again at a mean 12 years of follow-up.

CONCLUSION

High tibial osteotomy can be effective for periods longer than 15 years; however, results do deteriorate over time. Age less than 50 years, normal BMI, and ACL deficiency were independent factors associated with improved long-term survival of HTO.

Midterm follow-up of opening-wedge high tibial osteotomy

BACKGROUND

High tibial osteotomy is a valuable option for patients with varus gonarthrosis. To avoid difficulties with closing-wedge osteotomies, medial opening-wedge high tibial osteotomies have been advocated.

HYPOTHESIS

Opening-wedge high tibial osteotomy is a good option in highly active patients with varus gonarthrosis who would like to delay or prevent progression to total knee arthroplasty without activity restrictions.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty consecutive patients with varus gonarthrosis were treated with a medial opening-wedge high tibial osteotomy using the Puddu plate and allograft bone graft for a prospective study (14 men and 6 women; average age, 49.4 years [range, 36-67 years]). Gait analysis was performed preoperatively and at 6 months postoperatively. Preoperative radiographs, subjective ratings, and knee scores (Lysholm and Hospital for Special Surgery [HSS] scores) were obtained. At 2 years postoperatively and at the latest follow-up visit (average, 8.3 years), the subjective ratings and knee scores were repeated.

RESULTS

Gait analysis revealed an abnormal weightbearing pattern preoperatively with the vertical ground-reaction force. The postoperative vertical ground-reaction force revealed a normal double peak pattern. The preoperative adduction moment was 29% greater than the 6-month postoperative adduction moment. The preoperative varus averaged 3.6° and was corrected to an average of 7.5° of valgus postoperatively. All patients subjectively rated their preoperative knee as poor. At 2 years postoperatively, most patients (14) rated their knee as good, with 5 excellent and only 1 fair rating. The average preoperative Lysholm and HSS knee scores were 54.2 and 75.9, respectively, compared with the 2-year postoperative averages of 89.1 and 92.7, respectively. At 8 years postoperatively, there was 70% survivorship with 42% of patients rating their knees as good or excellent. Five patients (25%) had undergone total knee arthroplasty. Lysholm and HSS knee scores were 83.0 and 86.8, respectively, for the surviving knees at 8 years postoperatively.

CONCLUSION

Medial opening-wedge high tibial osteotomy produces good results in the midterm. After the osteotomy, a more normal appearing weightbearing pattern with double peaks was seen. The adduction moment significantly decreased, resulting in less contact pressure through the medial degenerative compartment of the knee. The authors recommend medial opening-wedge high tibial osteotomy for young patients with varus alignment and medial compartment arthritis to allow this patient population to remain highly active and delay progression to total knee arthroplasty without activity restrictions.

Effect of weight-bearing on the alignment after open wedge high tibial osteotomy

This study examined the changes in knee alignment after an open wedge high tibial osteotomy before and after weight-bearing. From 2004 to 2006, 36 high tibial osteotomies were performed to treat unicompartmental arthritis with a varus deformity. Thirteen patients without instability and with an accurate radiographic evaluation were included. The changes in the deviation of the mechanical axis and femorotibial angle were evaluated retrospectively using whole extremity radiographs immediately after surgery (supine position) and 4 months after surgery (weight-bearing position). In the nonweight-bearing radiograph obtained immediately after surgery, the mean deviation of the mechanical axis was 22% laterally and the mean femorotibial angle was valgus 8.9 degrees . The weight-bearing radiograph at 4 months after surgery showed that the former shifted laterally 34% and the latter shifted valgus 10.6 degrees . The changes in the mechanical axis and femorotibial angle were significant (P < 0.001). During open wedge high tibial osteotomy, the surgeon should consider the increase in deviation of the mechanical axis and femorotibial angle after weight-bearing.

Clinical results of reversed V-shaped high tibial corticotomy with minimally invasive surgery without internal fixation devices

High tibial osteotomy is a method of treating knee osteoarthritis due to genu varum in advanced stages. High tibial osteotomy-associated problems continue to be reported. The purpose of this study was to investigate the clinical results of a new, innovative method of high tibial osteotomy with 3- to 13-year follow-up. Between 1996 and 2006, our new surgical method was performed on 293 patients with medial compartment osteoarthritis and genu varum. All patients were examined preoperatively, 6 months postoperatively, and at final follow-up. The Hospital for Special Surgery Knee Scoring System (HSS) was used at final follow-up, and limb alignment and patient satisfaction were reassessed. Immediate postoperative complications included varus recurrence, knee instability, and peroneal nerve palsy, and no signs of tibial nonunion or infection were observed. At final follow-up, 3 cases of genu recurvatum, 2 cases of peroneal nerve palsy, and 25 cases of loss of correction were observed. Average postoperative HSS score was 85 (range, 47-97), and 97.8% of the patients were satisfied. This new method is a good alternative for the correction of genu varum because it requires a small incision, is soft tissue friendly, is a corticotomy instead of an osteotomy, requires no internal or external fixation devices, has a shorter duration and an acceptable complication and recurrence rate, and results in satisfactory HSS scores and higher patient satisfaction rates.

Closing wedge osteotomy of the tibia and the femur in the treatment of gonarthrosis

New developments in osteotomy techniques and methods of fixation have caused a renewed interest in closing wedge osteotomies of the tibia and femur in the treatment of gonarthrosis. The rationale, definition and techniques of closing wedge tibial and femoral osteotomies in the treatment of gonarthrosis are discussed. The principal indications include unicompartmental medial and much less so, varus knee gonarthrosis and unicompartmental lateral or valgus knee gonarthrosis with a well-maintained range of motion in patients who are physiologically young. Newer techniques have provided more rigid fixation and improved accuracy of correction.

Effective gait patterns for offloading the medial compartment of the knee

Gait modification offers a noninvasive option for offloading the medial compartment of the knee in patients with knee osteoarthritis. While gait modifications have been proposed based on their ability to reduce the external knee adduction moment, no gait pattern has been proven to reduce medial compartment contact force directly. This study used in vivo contact force data collected from a single subject with a force-measuring knee replacement to evaluate the effectiveness of two gait patterns at achieving this goal. The first was a "medial thrust" gait pattern that involved medializing the knee during stance phase, while the second was a "walking pole" gait pattern that involved using bilateral walking poles commonly used for hiking. Compared to the subject's normal gait pattern, medial thrust gait produced a 16% reduction and walking pole gait a 27% reduction in medial contact force over stance phase, both of which were statistically significant based on a two-tailed Mann-Whitney U-test. While medial thrust gait produced little change in lateral and total contact force over the stance phase, walking pole gait produced significant 11% and 21% reductions, respectively. Medial thrust gait may allow patients with knee osteoarthritis to reduce medial contact force using a normal-looking walking motion requiring no external equipment, while walking pole gait may allow patients with knee osteoarthritis or a knee replacement to reduce medial, lateral, and total contact force in situations where the use of walking poles is possible.

Staple versus locking compression plate fixation after lateral closing wedge high tibial osteotomy

PURPOSE

To compare the results of staple versus locking compression plate fixation after closing wedge high tibial osteotomy.

METHODS

A group of 23 patients (24 knees) who underwent box high tibial osteotomy and staple fixation was compared with another group of 19 patients (22 knees) who underwent a similar procedure but with locking compression plate fixation. Both groups were followed up for 3 years. The range of movement, Hospital for Special Surgery (HSS) Knee Score, time to full weight bearing, incidence of delayed union, femorotibial angle, and stage of osteoarthritis were compared.

RESULTS

At 6 months after the operation, the median HSS score and the proportion of patients with excellent or good scores were significantly higher in the locking compression plate than the staple fixation group (76 vs 62, p=0.003; 75% vs 42%, p=0.0354), but not at one and 3 years. The range of movement was significantly greater in the locking compression plate fixation group in the short term (6 weeks, 3 and 6 months), but not after one year. The median time to full weight bearing was significantly shorter in the locking compression plate fixation group (86 vs 116 days, p<0.001). There were fewer delayed unions in the locking compression plate fixation group but not significantly (1 vs 5, p=0.198), possibly because of the small numbers involved. There was no difference, within the limits of measurement error, in the femorotibial angle or correction loss between the 2 groups.

CONCLUSION

Locking compression plate fixation obviates the use of plaster casts, enables early mobilisation and bone union, and reduces the numbers with delayed union and the time to full weight bearing. Longer-term studies are needed to evaluate its effect on revarisation and arthropathy.

The long-term outcome of high tibial osteotomy: a ten- to 20-year follow-up

We carried out a prospective study of 132 patients (159 knees) who underwent closed-wedge high tibial osteotomy for severe medial compartment osteoarthritis between 1988 and 1997. A total of 94 patients (118 knees) was available for review at a mean of 16.4 years (16 to 20). Seven patients (7.4%) (11 knees) required conversion to total knee replacement. Kaplan-Meier survival was 97.6% (95% confidence interval 95.0 to 100) at ten years and 90.4% (95% confidence interval 84.1 to 96.7) at 15 years. Excellent and good results as assessed by the Hospital for Special Surgery knee score were achieved in 87 knees (73.7%). A pre-operative body mass index > 27.5 kg/m(2) and range of movement < 100 degrees were risk factors predicting early failure. Although our long-term results were satisfactory, strict indications for osteotomy are required if long-term survival is required.

Upper tibia osteotomy: long term results - realignment analysis using OASIS computer software

BACKGROUND

The normal values for axial alignment and joint line obliquity of the knee that indicate a successful valgus upper tibial osteotomy have not been established and reported in the literature.

METHODS

To identify those parameters we prospectively followed 51 patients with 54 lateral closing wedge upper tibial osteotomies performed after preoperative and postoperative analysis of standardized hip-to-ankle radiographs with a software computer program (OASIS).

RESULTS

Of the 54 knees, 18 (33.3%) underwent additional surgery. The average follow-up of the remaining 36 knees was 10 years (range 6.9-13.8 years). The cumulative osteotomy survival rate was 89% at 5 years and 76% at 10 years. Compared with patients whose postoperative femorotibial angle was 174 degrees -180 degrees , the patients whose postoperative femorotibial angle was <174 degrees or >180 degrees did worse with respect to osteotomy failure. Ten knees were at a decreased risk of failure. These knees had a postoperative femorotibial angle of 174 degrees -180 degrees , lateral joint line obliquity of <4 degrees , and a medial plateau force distribution of 40%-60%. The knees that met these criteria had 100% survival at 5 and 10 years, whereas the rest of the knees had survival rates of 86% and 70%, respectively.

CONCLUSIONS

We believe that using these criteria during preoperative planning may improve the survival of upper tibial osteotomy provided a precise, reproducible surgical technique and rigid fixation can be performed.

Effectiveness of medial-wedge insole treatment for valgus knee osteoarthritis

OBJECTIVE

To assess the efficacy of medial-wedge insoles in valgus knee osteoarthritis (OA).

METHODS

Thirty consecutive women with valgus-deformity knee OA > or = 8 degrees were randomized into 2 groups: medial insole (insoles with 8-mm medial elevation at the rearfoot [n = 16]) and neutral insole (similar insole without elevation [n = 14]). Both groups also wore ankle supports. A blinded examiner assessed pain on movement, at rest, and at night with a visual analog scale (VAS), the Lequesne index, and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index. Femorotibial, talocalcaneal, and talar tilt angles were evaluated at baseline and after 8 weeks of insole use.

RESULTS

Significant reductions in the medial insole group were observed for pain on movement (mean +/- SD VAS pre- and postintervention 8.1 +/- 1.5 versus 4.2 +/- 2.4; P = 0.001), at rest (5.1 +/- 2.3 versus 2.7 +/- 2.4; P = 0.002), and at night (6.1 +/- 2.7 versus 3.1 +/- 2.1; P = 0.001). In addition, a decrease in Lequesne (14.7 +/- 3.4 versus 9.6 +/- 3.8; P = 0.001) and WOMAC scores (74.1 +/- 14.2 versus 56.1 +/- 14.9; P = 0.001) was observed for the medial insole group. In the neutral insole group, a significant reduction was observed only for night pain (mean +/- SD VAS pre- and postintervention 5.8 +/- 2.4 versus 4.6 +/- 2.4; P = 0.019). An increase in femorotibial angle (169.0 +/- 3.4 versus 170.8 +/- 3.7; P = 0.001) occurred only in the medial insole group. Moreover, the difference in measured femorotibial angles pre- and postintervention was 1.84 +/- 1.42 versus -0.18 +/- 0.67 (P < 0.001) for the medial and neutral insole groups.

CONCLUSION

The use of medial-wedge insoles was highly effective in reducing pain at rest and on movement and promoted a functional improvement of valgus knee OA.

Impact of patellofemoral osteoarthritis on long-term outcome of high tibial osteotomy and effects of ventralization of tibial tubercle

BACKGROUND

Medial compartment osteoarthritis (OA) of the knee frequently accompanies patellofemoral osteoarthritis (PF-OA). No consensus has been reached whether it is better to include treatment for the PF joint at the time of high tibial osteotomy (HTO), or if treatment of the PF joint is unnecessary. The purpose of this comparative retrospective study on medial compartment OA of the knee accompanying PF-OA was to examine the effects of PF-OA on the long-term outcome of HTO and to evaluate the significance of ventralization of the tibial tubercle when combined with HTO.

METHODS

We studied the impact of PF-OA on the long-term outcome of HTO and the effects of ventralization of the tibial tubercle, which was performed in conjunction with HTO for medial and PF compartment OA more than 10 years previously. The 42 subjects included 14 men (15 knees) and 26 women (27 knees). Their mean age at the time of surgery was 60.7 years, and the follow-up period was 10-15 years (average 12 years). Ventralization of the tibial tubercle was performed on 18 knees.

RESULTS

A significant relation was observed between improvement of the clinical knee score and preoperative radiological PF-OA stage in the HTO patients (P < 0.05). Radiologically, no correlation was observed between the shift in radiological PF-OA stage and the presence or absence of ventralization of the tibial tubercle. Among the preoperative radiological moderate and severe PF-OA cases, no significant relation was found between the presence or absence of ventralization of the tibial tubercle performed with HTO and improvement of the knee joint function score.

CONCLUSION

In cases of severe PF-OA in which HTO was performed, ventralization of the tibial tubercle as combined surgery did not prove effective at the long-term follow-up.

Osteotomia tibial alta em pacientes com artrose do joelho

OBJETIVO: Avaliar o tratamento da gonartrose medial com osteotomia tibial tipo cunha de fechamento lateral associado à liberação da articulação tibiofibular proximal. MÉTODOS: Realizamos esta técnica associado com liberação da articulação tibiofibular proximal no tratamento da gonartrose medial em 36 pacientes (41 joelhos) de janeiro de 1995 a abril de 2003, com idade de 53,4 anos (média), seguidos por 51,6 meses (média). RESULTADOS: Na avaliação notamos que as osteotomias tibiais com cunha de fechamento lateral permitem correção satisfatória da deformidade fêmorotibial, com angulação femorotibial final em torno de 7º de valgo; o eixo mecânico foi desviado da região tibial medial (posição 1,2%) para o centro do joelho (posição 50,5%); a inclinação tibial na incidência perfil pré-operatória de 9,8º foi corrigida para 6,5º (média); a mobilidade articular apresentou perda de 2,3º na extensão (média). CONCLUSÃO: A técnica permite correção satisfatória da deformidade em varo fêmorotibial, porém não é isenta de complicações (14,6%). O grau de satisfação (Lysholm) dos pacientes teve incremento de 27,3 para 89. Assim, constitui uma parte essencial no arsenal de tratamento da gonartrose.

The patella and tibial condyle position after combined and after closing wedge high tibial osteotomy

High tibial osteotomy changes the patella and tibial condyle position, which makes the subsequent total knee replacement technically demanding. From 1 January 1993 to 31 December 2000, combined osteotomy [After the first osteotomy made 2 cm distally to the joint line, a bone wedge is removed based laterally. Its tip ends at the center of the tibial condyle (half bone wedge). The distal part of the tibia is placed into the valgus position and the half bone wedge is placed into the gap opened medially.] was performed on 103 knees and closing wedge osteotomy was performed on 47 consecutive knees. Eighty combined (group A) and 41 closing wedge (group B) osteotomy were studied. All knees were assessed radiologically before surgery, in the 10th postoperative week, in the 12th postoperative month and at the time of the final follow-up (in group A-66.15 months, in group B-66.61 months). We examined the change of the femorotibial angle, of the patellar height according to the method of Insall and Salvati, of the tibial slope angle according to the method of Bonnin, of the tibial condylar offset according to the method of Yoshida and of the distance between the lateral tibial plateau and the top of the fibular head. In group A and B, the recurrence of the varus deformity was not noted and valgus alignment did not increase in any case. In group-A, the Insall-Salvati ratio remained unchanged in 65% of knees. The tibial slope angle decreased in both groups. There was correlation between the change of the tibial condylar offset and the angle of the correction in both groups. There was correlation between the change of the distance between the lateral tibial plateau and the top of the fibular head. After combined osteotomy, the transposition of the tibial condyle and the decrease of the distance between the lateral tibial plateau and the top of the fibular head was less than after closing wedge osteotomy, although the average angle of correction was more after combined osteotomy (11.835 degrees ), than after closing wedge osteotomy (9.465 degrees ). Theoretically, the recurrence of the varus deformity, the increase of the valgus alignment and (in majority of cases) the shortening of the patellar tendon do not compromise the likelihood of successful conversion to the subsequent total knee replacement, either after combined or after closing wedge osteotomy. The combined osteotomy does not lead to considerable transposition of the tibial condyle and to considerable lateral tibial bone loss; therefore, theoretically, the combined osteotomy does not impair the subsequent total knee replacement.

Osteotomy for the Early Varus Arthritic Knee

High tibial osteotomy is a well-established procedure for the management of medial compartment arthritis that is currently experiencing a resurgence in popularity. A number of techniques have been described, with the ultimate goal of obtaining appropriate alignment to provide pain relief and functional improvement over a long-term period. Appropriate patient selection and careful surgical technique is necessary to achieve these goals with a minimal risk of complication. Newer technology such as computer navigation promises to improve the overall accuracy of the procedure. The need for alignment correction in combination with ligament reconstruction and chondral resurfacing surgery will increase the indications for this procedure. This article discusses the techniques available for high tibial osteotomy, the results and relative advantages of each, and the appropriate surgical technique to achieve optimal results while minimizing complications.

Tibial slope and high tibial osteotomy using the circular external fixator

Alteration of tibial slope is one of the important anatomical changes of the proximal tibia after high tibial osteotomy. Increased or decreased tibial slope can effect further total knee prosthesis procedure. In this retrospective study, 18 knees of 17 patients (17 female, mean age 51 range 43-61, mean BMI is 33.6 +/- 4.6 kg/m2) who were applied high tibial osteotomy using circular external fixator due to medial compartment arthrosis of the knee were evaluated in terms of tibial slope changes. While mean correction about 12.3 degrees in mechanical femoro-tibial angle was obtained in frontal plan (P = 0.0001), significant change in tibial slope was not determined in sagittal plan (P = 0.127). The mean posterior proximal femoral angle values were measured as 79.5 +/- 2.1 degrees preoperatively and as 80.3 +/- 2.7 degrees postoperatively and found to fall into the normal range (80.4 +/- 1.6 degrees). As there is no significant alteration in tibial slope after high tibial osteotomy performed with the Ilizarov system, complications due to alteration in tibial slope will not be experienced in follow-up or in further total knee prosthesis procedure.

Influence of high tibial osteotomy on bone marrow edema in the knee

To determine the influence of high tibial osteotomy on subchondral bone marrow edema in medial osteoarthritis of the varus knee, full leg-length radiographs and magnetic resonance imaging were performed in 20 patients (20 knees) before surgery, 1 year postoperatively, and at a mean of 7 years postoperatively. The extent of bone marrow edema in the medial compartment was quantified with magnetic resonance imaging in two planes using the formula for a prolate ellipsoid as follows: length x width x depth x pi/6. We used the Japanese Orthopaedic Association knee score for clinical evaluation. At the last followup, all knees with valgus alignment (10/10) showed reduced edema. In contrast, bone marrow edema increased or remained unchanged in four of 10 knees with neutral or varus alignment. The percentage of satisfactory results was 100% (10/10) in valgus knees and only 30% (3/10) in neutral or varus knees. Extent of bone marrow edema at the followup correlated with the mechanical axis and knee score. Because of the prognostic value of bone marrow abnormalities in the medial compartment observed on magnetic resonance imaging, early lateral closing wedge osteotomy should be considered in patients with varus malalignment and bone marrow edema even in mild cases of medial osteoarthritis.

Influence of lower-limb torsion on long-term outcomes of tibial valgus osteotomy for medial compartment knee osteoarthritis

BACKGROUND

The results of tibial osteotomy used to treat osteoarthritis of the medial compartment of the knee deteriorate over time even when the initial correction is optimal. Studies have shown that tibial and femoral torsion and the femorotibial index (tibial torsion minus femoral torsion) contribute, together with coronal malalignment, to the development of single-compartment knee osteoarthritis. The objective of our study was to evaluate the impact of femoral and tibial torsion and of coronal realignment on the long-term clinical and radiographic outcomes of valgus tibial osteotomy.

METHODS

A function score was calculated for sixty-eight patients at a mean of thirteen years after the osteotomy. Anteroposterior single-leg-stance radiographs were used to evaluate loss of the femorotibial joint space. Goniometry was used to measure coronal malalignment preoperatively, at one year, and at the time of the last follow-up, and postoperative computed tomography was performed to measure femoral anteversion and tibial torsion and to calculate the femorotibial index. We looked for associations linking body mass index, initial loss of joint space, coronal malalignment, femoral and tibial torsion, the femorotibial index, and functional outcomes.

RESULTS

Worse outcomes were associated with changes in coronal alignment (>/=2 degrees ) over time, which were associated with deterioration of the femorotibial space. Femoral anteversion was significantly greater in patients in whom valgus increased over time than in those in whom valgus decreased over time. Stability of coronal alignment seemed to be dependent on a linear relationship between the femorotibial index and the degree of postoperative realignment. A body mass index of >25 kg/m(2) was associated with a long-term loss of coronal realignment. Preoperative loss of the medial femorotibial joint space, coronal alignment at one year, and age were not associated with secondary malalignment or functional outcomes.

CONCLUSIONS

Long-term success of a valgus tibial osteotomy is related to the stability over time of the postoperative coronal realignment. Therefore, the results of our study suggest that modifying the realignment according to the extent of femoral anteversion may improve long-term outcomes.

A 12-28-year followup study of closing wedge high tibial osteotomy

Current indications for high tibial osteotomy (HTO) are controversial although several risk factors have been associated with HTO survival. We ascertained the influence of preoperative variables in a consecutive series of patients who had closing wedge HTO at a minimum of 12 year followup (mean 18-year, range 12 to 28 years). Three hundred one of an initial 372 high tibial osteotomies (313 patients) were included (81% followup); 71 knees were eliminated because patients died (30 knees) or were lost to followup (41 knees). The mean age was 42 years (range, 15-76 years), 194 were men and 119 were women. The osteotomy was fixed by a Blount staple and an AO half-tube plate with three screws. Forty-three knees (14%) in 39 patients were revised for progression of osteoarthritis at an average of 102 months. Survival was 85% at 20 years with revision as the endpoint. Knee function was considered satisfactory by 77% of patients. At final followup, 1/2 of the knees showed radiographic signs of medial osteoarthritis. The most important risk factors predicting revision were age greater than 50 years and a preoperative arthritis Ahlback grade of 3 or more.