Treatment of Symptomatic Varus Osteoarthritis of the Knee

Osteoarthritis (OA) is the 6th leading cause of Years Lost to Disability (YLD) at global level, accounting for 3% of total global YLDs. Knee OA is the most common joint disorder, and in the Netherlands approximately 17% of the population aged 45 years and over suffer from knee OA. It causes considerable pain and immobility, affects independence and psychosocial functioning, and in addition leads to financial losses. Many patients present with unicompartmental disease, and the medial compartment is almost 10 times more frequently involved than the lateral compartment. This thesis investigates both the non-operative and surgical treatment outcomes in active patients with symptomatic medial OA of the knee. The aim is to clarify indications for identified treatment modalities as controversy exists on how patient and/or intervention related factors affect the outcome of this disease. Furthermore, clearer indications will lead to better care, which may not only benefit the individual patient but also society as a whole because of expected savings in health care expenses and reduction of productivity losses. Patients with OA of the medial compartment often have varus malalignment; the mechanical axis and load bearing passes through the medial compartment. Some report that malalignment may even have an impact on the development and progression of knee OA. Although many consider whole leg radiographs in standing position (mechanical axis measurement) as the gold standard to determine knee alignment, in clinical practice, knee alignment is often assessed on shorter anterior-posterior knee radiographs (anatomic axis measurement) to cut expenses and cumbersome procedures. Significant correlation between mechanical and anatomic axis angles has been reported. Some suggest using anatomic axis measurement in research and clinical settings. In Chapter 2 we compare two different methods of anatomic axis assessment in a group of patients with known mechanical varus alignment, and determine whether or not anatomic axis measurement on standard short knee views can be used in clinical settings

Total knee arthroplasty after high tibial osteotomy. A systematic review

Background: Previous osteotomy may compromise subsequent knee replacement, but no guidelines considering knee arthroplasty after prior osteotomy have been developed. We describe a systematic review of non-randomized studies to analyze the effect of high tibial osteotomy on total knee arthroplasty. Methods: A computerized search for relevant studies published up to September 2007 was performed in Medline and Embase using a search strategy that is highly sensitive to find nonrandomized studies. Included were observational studies in which patients had total knee arthroplasty performed after prior high tibial osteotomy. Studies that fulfilled these criteria, were assessed for methodologic quality by two independent reviewers using the critical appraisal of observational studies developed by Deeks and the MINORS instrument. The study characteristics and data on the intervention, follow-up, and outcome measures, were extracted using a pre-tested standardized form. Primary outcomes were: knee range of motion, knee clinical score, and revision surgery. The grade of evidence was determined using the guidelines of the GRADE working group. Results: Of the 458 articles identified using our search strategy, 17 met the inclusion criteria. Fifteen studies were cohort study with a concurrent control group, one was a historical cohort study and one a case-control study. Nine studies scored 50% or more on both methodological quality assessments. Pooling of the results was not possible due to the heterogeneity of the studies, and our analysis could not raise the overall low quality of evidence. No significant differences between primary total knee arthroplasty and total knee arthroplasty after osteotomy were found for knee range of motion in four out of six studies, knee clinical scores in eight out of nine studies, and revision surgery in eight out of eight studies after a median follow-up of 5 years. Conclusion: Our analysis suggests that osteotomy does not compromise subsequent knee replacement. However, the low quality of evidence precludes solid clinical conclusions

Osteotomy for treating knee osteoarthritis

Background: Patients with unicompartmental osteoarthritis of the knee can be treated with a correction osteotomy. The goal of the correction osteotomy is to transfer the load bearing from the pathologic to the normal compartment of the knee. A successful outcome of the osteotomy relies on proper patient selection, stage of osteoarthritis, achievement and maintenance of adequate operative correction. This is an update of the original review published in Issue 1, 2005. Objectives: To assess the effectiveness and safety of an osteotomy for treating osteoarthritis of the knee. Search strategy: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE (Current contents, Health STAR) up to October 2002 in the original review and in the update until May 2007. Reference lists of identified trials were screened. Selection criteria: Randomised and controlled clinical trials comparing a high tibial osteotomy or a distal femoral osteotomy in patients with unicompartmental osteoarthritis of the medial or lateral compartment of the knee. Data collection and analysis: Two review authors independently selected trials, extracted data and assessed trial quality. Due to heterogeneity of the studies, pooling of outcome measures was not possible. Main results: Thirteen studies involving over 693 people were included; 11 studies were included in the first version and two studies and one longer follow-up study were included in this update. All studies concerned a valgus high tibial osteotomy (HTO) for medial compartment osteoarthritis of the knee. Six studies, in which two studies were included in this update, compared two techniques of HTO. One study compared HTO alone versus HTO with additional treatment. Four studies compared within the same type of HTO, different perioperative conditions (two studies) or two different types of post-operative treatment (two studies). Two studies, including the longer follow up, compared HTO with unicompartmental joint replacement. No study compared an osteotomy with conservative treatment. Most studies showed improvement of the patient (less pain and improvement of function scores) after osteotomy surgery, but in the majority of the studies there was no significant difference with other operative treatment (other technique of HTO/ unicompartmental joint replacement). Overall, the methodological quality was low. Authors' conclusions: Based on 13 studies, we conclude that there is 'silver' level evidence (www.cochranemsk.org) that valgus HTO improves knee function and reduces pain. There is no evidence whether an osteotomy is more effective than conservative treatment and the results so far do not justify a conclusion about effectiveness of specific surgical techniques. Copyrigh

Do Laterally Wedged Insoles or Valgus Braces Unload the Medial Compartment of the Knee in Patients With Osteoarthritis?

Background: The results of conservative treatment of knee osteoarthritis (OA) are generally evaluated in epidemiological studies with clinical outcome measures as primary outcomes. Biomechanical evaluation of orthoses shows that there are potentially beneficial biomechanical changes to joint loading; however, evaluation in relation to clinical outcome measures in longitudinal studies is needed.Questions/purposes: We asked (1) is there an immediate effect on gait in patients using a laterally wedged insole or valgus knee brace; (2) is there a late (6 weeks) effect; and (3) is there a difference between subgroups within each group with respect to patient compliance, body mass index, and OA status?Methods: This was a secondary analysis of data from a previous randomized controlled trial of patients with early medial knee OA. A total of 91 patients were enrolled in that trial, and 73 (80%) completed it after 6 months. Of the enrolled patients, 80 (88%) met prespecified inclusion criteria for analysis in the present study. The patients were randomized to an insole or brace. Gait was analyzed with and without wearing the orthosis (insole or brace) at baseline and after 6 weeks. Measurements were taken of the knee adduction moment, ground reaction force, moment arm, walking speed, and toe-out angle. Data were analyzed with regression analyses based on an intention-to-treat principle.Results: A mean reduction of 4% (± 10) (95% confidence interval [CI], −0.147 to −0.03, p = 0.003) of the peak knee adduction moment and 4% (± 13) (95% CI, −0.009 to −0.001, p = 0.01) of the moment arm at baseline was observed in the insole group when walking with an insole was compared with walking without an insole. A m