Early Versus Delayed Microdiscectomy for Chronic Sciatica Lasting 4-12 Months Secondary to Lumbar Disc Herniation: A Secondary Analysis of a Randomized Controlled Trial.

OBJECTIVES: To compare the effect of delaying surgery on clinical outcome in patients with chronic sciatica secondary to lumbar disc herniation. METHODS: Patients with sciatica lasting 4-12 months and lumbar disc herniation at the L4-L5 or L5-S1 level were randomized to undergo microdiscectomy (early surgery) or to receive 6 months of nonoperative treatment followed by surgery if needed (delayed surgery). Outcomes were leg pain, Oswestry Disability Index score (ODI), back pain, SF-36 physical component (PCS) and mental component (MCS) summary scores, employment, and satisfaction measured preoperatively and at 6 weeks, 3 months, 6 months, and 1 year after surgery. RESULTS: Of the 64 patients in the early surgery group, 56 underwent microdiscectomy an average of 3 ± 2 weeks after enrollment. Of the 64 patients randomized to nonoperative care, 22 patients underwent delayed surgery an average of 53 ± 24 weeks after enrollment. The early surgery group experienced less leg pain than the delayed surgery group, which was the primary outcome, at 6 months after surgery (early surgery 2.8 ± .4 vs delayed surgery 4.8 ± .7; difference, 2.0; 95% confidence interval, .5-3.5). The overall estimated mean difference between groups significantly favored early surgery for leg pain, ODI, SF36-PCS, and back pain. The adverse event rate was similar between groups. CONCLUSIONS: Patients presenting with chronic sciatica treated with delayed surgery after prolonging standardized non-operative care have inferior outcomes compared to those that undergo expedited surgery.

Exploring indicators of extremity pain of spinal source as identified by Mechanical Diagnosis and Therapy (MDT): a secondary analysis of a prospective cohort study.

OBJECTIVE: To explore indicators that predict whether patients with extremity pain have a spinal or extremity source of pain. METHODS: The data were from a prospective cohort study (n = 369). Potential indicators were gathered from a typical Mechanical Diagnosis and Therapy (MDT) history and examination. A stepwise logistic regression with a backward elimination was performed to determine which indicators predict classification into spinal or extremity source groups. A Receiver Operating Characteristic (ROC) curve was constructed to examine the number of significant indicators that could predict group classification. RESULTS: Five indicators were identified to predict group classification. Classification into the spinal group was associated with the presence of paresthesia [odds ratio (OR) 1.984], change in symptoms with sitting/neck or trunk flexion/turning neck/when still (OR 2.642), change in symptoms with posture change (OR 3.956), restrictions in spinal movements (OR 2.633), and no restrictions in extremity movements (OR 2.241). The optimal number of indicators for classification was two (sensitivity = 0.638, specificity = 0.807). DISCUSSION: This study provides guidance on clinical indicators that predict the source of symptoms for isolated extremity pain. The clinical indicators will allow clinicians to supplement their decision-making process in regard to spinal and extremity differentiation so as to appropriately target their examinations and interventions.

Microdiscectomy Is More Cost-effective Than a 6-Month Nonsurgical Care Regimen for Chronic Radiculopathy.

BACKGROUND: A recent randomized controlled trial (RCT), performed by the authors, comparing early surgical microdiscectomy with 6 months of nonoperative care for chronic lumbar radiculopathy showed that early surgery resulted in improved outcomes. However, estimates of the incremental cost-utility ratio (ICUR), which is often expressed as the cost of gaining one quality-adjusted life year (QALY), of microdiscectomy versus nonsurgical management have varied. Radiculopathy lasting more than 4 months is less likely to improve without surgical intervention and may have a more favorable ICUR than previously reported for acute radiculopathy. QUESTION/PURPOSE: In the setting of chronic radiculopathy caused by lumbar disc herniation, defined as symptoms and/or signs of 4 to 12 months duration, is surgical management more cost-effective than 6 months of nonoperative care from the third-party payer perspective based on a willingness to pay of less than CAD 50,000/QALY? METHODS: A decision analysis model served as the vehicle for the cost-utility analysis. A decision tree was parameterized using data from our single-center RCT that was augmented with institutional microcost data from the Ontario Case Costing Initiative. Bottom-up case costing methodology generates more accurate cost estimates, although institutional costs are known to vary. There were no major surgical cost drivers such as implants or bone graft substitutes, and therefore, the jurisdictional variance would be minimal for tertiary care centers. QALYs derived from the EuroQoL-5D were the health outcome and were derived exclusively from the RCT data, given the paucity of studies evaluating the surgical treatment of lumbar radiculopathy lasting 4 to 12 months. Cost-effectiveness was assessed using the ICUR and a threshold of willingness to pay CAD 50,000 (USD 41,220) per QALY in the base case. Sensitivity analyses were performed to account for the uncertainties within the estimate of cost utility, using both a probabilistic sensitivity analysis and two one-way sensitivity analyses with varying crossover rates after the 6-month nonsurgical treatment had concluded. RESULTS: Early surgical treatment of patients with chronic lumbar radiculopathy (defined as symptoms of 4 to 12 months duration) was cost-effective, in that the cost of one QALY was lower than the CAD 50,000 threshold (note: the purchasing power parity conversion factor between the Canadian dollar (CAD) and the US dollar (USD) for 2019 was 1 USD = 1.213 CAD; therefore, our threshold was USD 41,220). Patients in the early surgical treatment group had higher expected costs (CAD 4118 [95% CI 3429 to 4867]) than those with nonsurgical treatment (CAD 2377 [95% CI 1622 to 3518]), but they had better expected health outcomes (1.48 QALYs [95% CI 1.39 to 1.57] versus 1.30 [95% CI 1.22 to 1.37]). The ICUR was CAD 5822 per QALY gained (95% CI 3029 to 30,461). The 2-year probabilistic sensitivity analysis demonstrated that the likelihood that early surgical treatment was cost-effective was 0.99 at the willingness-to-pay threshold, as did the one-way sensitivity analyses. CONCLUSION: Early surgery is cost-effective compared with nonoperative care in patients who have had chronic sciatica for 4 to 12 months. Decision-makers should ensure adequate funding to allow timely access to surgical care given that it is highly likely that early surgical intervention is potentially cost-effective in single-payer systems. Future work should focus on both the clinical effectiveness of the treatment of chronic radiculopathy and the costs of these treatments from a societal perspective to account for occupational absences and lost patient productivity. Parallel cost-utility analyses are critical so that appropriate decisions about resource allocation can be made. LEVEL OF EVIDENCE: Level III, economic and decision analysis.

Discectomy Compared with Standardized Nonoperative Care for Chronic Sciatica Due to a Lumbar Disc Herniation: A Secondary Analysis of a Randomized Controlled Trial with 2-Year Follow-up.

BACKGROUND: Randomized controlled trials evaluating acute sciatica have not demonstrated prolonged improvements in terms of patient-reported pain and function. For chronic sciatica, however, microdiscectomy has been found to be superior at 1 year. Whether this effect persists during the second year is not known. The purpose of the present study was to report the 2-year outcomes following lumbar microdiscectomy as compared with standardized nonoperative care for the treatment of chronic sciatica resulting from a lumbar disc herniation. METHODS: The present study is a secondary analysis of a previously reported randomized controlled trial with extension to 2 years of follow-up. Patients with radiculopathy for 4 to 12 months resulting from an L4-L5 or L5-S1 disc herniation were randomized to microdiscectomy or 6 months of nonoperative care followed by surgery if needed. Intention-to-treat analysis was performed at 2 years for the primary outcome (the intensity of leg pain) (range of possible scores, 0 [no pain] to 10 [worst pain]) as well as for secondary outcomes (including the Oswestry Disability Index score, the intensity of back pain, and quality of life). RESULTS: One hundred and twenty-eight patients were randomized in the present study. Twenty-four (38%) of the 64 patients who had been randomized to nonoperative care crossed over to surgical treatment by 2 years following enrollment. At the 2-year time point, the follow-up rate was approximately 70%. At 2 years, the operative group had less leg pain than the nonoperative group (mean, 2.8 ± 0.4 compared with 4.2 ± 0.4; treatment effect, 1.3 [95% confidence interval, 0.3 to 2.4]). The treatment effect favored surgery for all secondary outcome measures at 6 months and 1 year and for back pain intensity and physical function at 2 years. CONCLUSIONS: At 2 years, the present study showed that microdiscectomy was superior to nonoperative care for the treatment of chronic sciatica resulting from an L4-L5 or L5-S1 disc herniation. However, the difference between the groups did not surpass the minimal clinically important difference at 2 years as was reached at earlier follow-up points, likely as the result of patients crossing over from nonoperative to operative treatment. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

The McKenzie Method and its association with psychosocial outcomes in low back pain: a systematic review.

Study Design: Systematic Literature Review.Background: The McKenzie Method (MDT) is a comprehensive conservative approach commonly used for the management of low back pain (LBP); however, its association with psychosocial outcomes in this population is less clear.Objectives: Evaluate whether MDT has an association with psychosocial outcomes for individuals with LBP.Methods: The following electronic databases were searched: Medline, Pubmed, Cochrane, CINAHL, Embase and AMED. They were systematically searched from the date of inception to August 2019. Included studies had to have participants experiencing LBP who were over 18 years old, utilize MDT as an assessment or intervention, and report outcomes for at least one psychosocial variable. Three reviewers independently evaluated methodological quality of randomized control trials (RCT) using the PEDro scale and observational studies using the GRACE scale.Results: The initial search resulted in 181 articles to review. After screening abstracts, then full articles, a total of 16 studies were included, 5 of which were RCTs rated 5-8/10 on the PEDro scale. A qualitative review was performed and the studies' results were synthesized into five main findings: fear-avoidance beliefs, depression symptoms, pain self-efficacy, psychological distress, and return to work (RTW).Conclusions: There is evidence that MDT has an association with improving fear-avoidance beliefs, pain self-efficacy, depression, and psychological distress. These results should be interpreted with caution as further high-quality randomized control trials addressing this topic are necessary due to the varying methodological and statistical constructs of the included studies.

Surgery versus Conservative Care for Persistent Sciatica Lasting 4 to 12 Months.

BACKGROUND: The treatment of chronic sciatica caused by herniation of a lumbar disk has not been well studied in comparison with acute disk herniation. Data are needed on whether diskectomy or a conservative approach is better for sciatica that has persisted for several months. METHODS: In a single-center trial, we randomly assigned patients with sciatica that had lasted for 4 to 12 months and lumbar disk herniation at the L4-L5 or L5-S1 level in a 1:1 ratio to undergo microdiskectomy or to receive 6 months of standardized nonoperative care followed by surgery if needed. Surgery was performed by spine surgeons who used conventional microdiskectomy techniques. The primary outcome was the intensity of leg pain on a visual analogue scale (ranging from 0 to 10, with higher scores indicating more severe pain) at 6 months after enrollment. Secondary outcomes were the score on the Oswestry Disability Index, back and leg pain, and quality-of-life scores at 6 weeks, 3 months, 6 months, and 1 year. RESULTS: From 2010 through 2016, a total of 790 patients were screened; of those patients, 128 were enrolled, with 64 in each group. Among the patients assigned to undergo surgery, the median time from randomization to surgery was 3.1 weeks; of the 64 patients in the nonsurgical group, 22 (34%) crossed over to undergo surgery at a median of 11 months after enrollment. At baseline, the mean score for leg-pain intensity was 7.7 in the surgical group and 8.0 in the nonsurgical group. The primary outcome of the leg-pain intensity score at 6 months was 2.8 in the surgical group and 5.2 in the nonsurgical group (adjusted mean difference, 2.4; 95% confidence interval, 1.4 to 3.4; P<0.001). Secondary outcomes including the score on the Owestry Disability Index and pain at 12 months were in the same direction as the primary outcome. Nine patients had adverse events associated with surgery, and one patient underwent repeat surgery for recurrent disk herniation. CONCLUSIONS: In this single-center trial involving patients with sciatica lasting more than 4 months and caused by lumbar disk herniation, microdiskectomy was superior to nonsurgical care with respect to pain intensity at 6 months of follow-up. (Funded by Physicians' Services Incorporated Foundation; ClinicalTrials.gov number, NCT01335646.).

Physiotherapy assessment and treatment of chronic subjective tinnitus using mechanical diagnosis and therapy: a case report.

Objectives: Tinnitus is the perception of sound without any external auditory stimulus. Cervicogenic somatic tinnitus (CST) is a subset in which symptoms are modulated by maneuvers of the neck. The evidence for effective diagnosis and treatment of CST is limited. Mechanical Diagnosis and Therapy (MDT) is a biopsychosocial assessment and management system that uses the response to mechanical forces to classify clinical presentations accurately. The purpose of this case report is to describe the MDT assessment and management of a patient with chronic subjective tinnitus.Methods: A 67-year-old female with a 5-year history of left-sided subjective tinnitus, neck pain, and headache was referred for physiotherapy. Outcome measures included the Visual Analogue Scale (VAS), Tinnitus Handicap Inventory (THI), and Neck Disability Index (NDI). She was evaluated and treated according to MDT principles with management consisting of individualized directional preference exercises and postural correction.Results: Significant improvements in symptoms, cervical range of motion, function, and psychosocial status were observed over the long-term. At 6 months, THI scores dropped from 62/100 to 18/100 and NDI scores dropped from 18/50 to 3/50.Discussion: A comprehensive MDT assessment led to a classification of Derangement, with treatment focusing on tailored self-management. Contrary to other interventions described for CST, the patient was able to make significant and lasting changes to her symptoms without the need for any externally applied interventions. The emphasis on self-management dovetails well with the biopsychosocial model of care. This case provides preliminary evidence for the utility of screening for Derangement in conservative tinnitus assessments.Level of Evidence: 4.

A study exploring the prevalence of Extremity Pain of Spinal Source (EXPOSS).

OBJECTIVES: To investigate the proportion of patients that present with isolated extremity pain who have a spinal source of symptoms and evaluate the response to spinal intervention. METHODS: Participants (n = 369) presenting with isolated extremity pain and who believed that their pain was not originating from their spine, were assessed using a Mechanical Diagnosis and Therapy differentiation process. Numerical Pain Rating Scale, Upper Extremity/Lower Extremity Functional Index and the Orebro Questionnaire were collected at the initial visit and at discharge. Global Rating of Change outcomes were collected at discharge. Clinicians provided MDT 'treatment as usual'. A chi-square test examined the overall significance of the comparison within each region. Effect sizes between spinal and extremity source groups were calculated for the outcome scores at discharge. RESULTS: Overall, 43.5% of participants had a spinal source of symptoms. Effect sizes indicated that the spinal source group had improved outcomes at discharge for all outcomes compared to the extremity source group. DISCUSSION: Over 40% of patients with isolated extremity pain, who believed that their pain was not originating from the spine, responded to spinal intervention and thus were classified as having a spinal source of symptoms. These patients did significantly better than those whose extremity pain did not have a spinal source and were managed with local extremity interventions. The results suggest the spine is a common source of extremity pain and adequate screening is warranted to ensure the patients ́ source of symptoms is addressed.

The use of Mechanical Diagnosis and Therapy (MDT) in patients with lower urinary tract symptoms (LUTS): case series.

Lower urinary tract symptoms (LUTS) are highly prevalent among men over the age of 40. Even though associations between lumbar spine conditions and LUTS have been documented in the literature, no studies have detailed a specific lumbar assessment and classification process, and the related treatment effects in patients with LUTS. In this case series, we present three male patients with LUTS as primary complaints, who were evaluated and treated with Mechanical Diagnosis and Therapy (MDT) for the lumbar spine. The duration of their symptoms was between 4 months and 7 years. Urogenital pathologies were ruled out for all patients. The Chronic Prostatitis Symptom Index was used as a functional outcome measure. All patients were classified as having lumbar derangements. Treatment of derangements with directional preference exercises resulted in the improvement of their LUTS, with clinically significant improvements (56.0%-77.4%) in functional outcome measures over an average of six sessions. Preliminary indications suggest that these LUTS cases may possibly have had a lumbar spine origin and "mechanical" nature. Therefore, they may be within the scope of MDT assessments and interventions. With careful monitoring of symptoms, MDT may serve as a screening tool and conservative treatment option.

An international survey of the comprehensiveness of the McKenzie classification system and the proportions of classifications and directional preferences in patients with spinal pain.

BACKGROUND: Classification of spinal pain has been a key goal identified in the research. However it is not clear if existing classification systems are comprehensive. OBJECTIVE: To examine the comprehensiveness and distribution of classifications within the McKenzie classification system (MDT), and the directional preference in consecutive patients with spine pain. STUDY DESIGN: Prospective, observational study. METHODS: Clinicians with a Diploma in MDT provided data on patients that they had assessed, classified, managed, and then confirmed their classification at discharge. They provided data on the spinal area, the MDT classification, and the loading strategy used in management. RESULTS: Fifty-four clinicians from at least 15 different countries provided data on 750 patients: lumbar 64.8%, cervical 29.6%, thoracic 5.6%. The distribution of classifications was as follows: Derangement 75.4%, OTHER 22.8%, Dysfunction 1.7%, Postural syndrome 0.1%. In Derangements 82.5% had a directional preference for extension, 12.9% for lateral forces, and 4.6% for flexion. Those patients classified as one of the OTHER subgroups were given specific classifications. CONCLUSION: Derangement was the most common classification and extension was by far the most common directional preference. A substantial proportion were classified as OTHER subgroups, for whom management is less straightforward.

Consistency of commonly used orthopedic special tests of the shoulder when used with the McKenzie system of mechanical diagnosis and therapy.

BACKGROUND: Shoulder Orthopedic Special Tests (OSTs) are used to assist with diagnosis in shoulder disorders. Issues with reliability and validity exist, making their interpretation challenging. Exploring OST results on repeated testing within Mechanical Diagnosis and Therapy (MDT) shoulder classifications may offer insight into the poor performance of these tests. OBJECTIVES: To investigate in patients with shoulder complaints, whether MDT classifications affect the agreement of OST results over the course of treatment. METHODS: An international group of MDT clinicians recruited 105 patients with shoulder problems. Three commonly used OSTs (Empty Can, Hawkins-Kennedy, and Speed's tests) were utilized. Results of the OSTs were collected at sessions 1, 3, 5 and 8, or at discharge from an MDT classification-based treatment. The Kappa statistic was utilized to determine the agreement of the OST results over time for each of the MDT classifications. RESULTS: The overall Kappa values for Empty Can, Hawkins-Kennedy and Speed's tests were 0.28 (SE = 0.07), 0.28 (SE = 0.07) and 0.29 (SE = 0.07), respectively. The highest level of agreement was for Articular Dysfunction for the Empty Can test (0.84, SE = 0.19). For shoulder Derangements, there was no agreement for any of the OSTs (P values > 0.05). CONCLUSION: The lack of agreement when the OSTs were consecutively tested in the presence of the MDT Derangement classification contrasted with the other MDT classifications. The presence of Derangement was responsible for reducing the overall agreement of commonly used OSTs and may explain the poor consistency for OSTs.

Inter-examiner classification reliability of Mechanical Diagnosis and Therapy for extremity problems - Systematic review.

BACKGROUND: Mechanical Diagnosis and Therapy (MDT) is used in the treatment of extremity problems. Classifying clinical problems is one method of providing effective treatment to a target population. Classification reliability is a key factor to determine the precise clinical problem and to direct an appropriate intervention. OBJECTIVES: To explore inter-examiner reliability of the MDT classification for extremity problems in three reliability designs: 1) vignette reliability using surveys with patient vignettes, 2) concurrent reliability, where multiple assessors decide a classification by observing someone's assessment, 3) successive reliability, where multiple assessors independently assess the same patient at different times. DESIGN: Systematic review with data synthesis in a quantitative format. METHOD: Agreement of MDT subgroups was examined using the Kappa value, with the operational definition of acceptable reliability set at ≥ 0.6. The level of evidence was determined considering the methodological quality of the studies. RESULTS/FINDINGS: Six studies were included and all studies met the criteria for high quality. Kappa values for the vignette reliability design (five studies) were ≥ 0.7. There was data from two cohorts in one study for the concurrent reliability design and the Kappa values ranged from 0.45 to 1.0. Kappa values for the successive reliability design (data from three cohorts in one study) were < 0.6. CONCLUSION: The current review found strong evidence of acceptable inter-examiner reliability of MDT classification for extremity problems in the vignette reliability design, limited evidence of acceptable reliability in the concurrent reliability design and unacceptable reliability in the successive reliability design.

Inter-rater reliability of the McKenzie System of Mechanical Diagnosis and Therapy in the examination of the knee.

OBJECTIVE: The McKenzie System of Mechanical Diagnosis and Therapy (MDT) is a widely used method of classification and management of musculoskeletal problems. Although MDT has been investigated for its reliability and efficacy in the management of spinal pain, few studies have evaluated the system when applying it to musculoskeletal problems in the extremities, in particular the knee. The purpose of this study was to investigate the inter-rater reliability of MDT when classifying clinical vignettes describing patients with musculoskeletal knee pain. METHODS: This study was divided into two phases. First, 10 clinicians experienced in the use of MDT were recruited to write a total of 60 clinical vignettes based upon the initial assessment of their past patients with knee pain. Second, six different MDT raters were recruited to rate 53 selected vignettes and reliability was determined using Fleiss Kappa. RESULTS: There was 'substantial agreement' among six MDT raters classifying the clinical vignettes into one of four categories (κ = 0.72). There was no statistically significant difference between therapists with different levels of training. DISCUSSION: MDT demonstrated acceptable reliability among trained raters to classify clinical vignettes describing patients with musculoskeletal knee pain. To generalize the use of the system to more users, future research should continue to investigate the reliability of MDT using raters with lower levels of training and experience and assess reliability in real patients. LEVEL OF EVIDENCE: 5.

Application of the McKenzie system of Mechanical Diagnosis and Therapy (MDT) in patients with shoulder pain; a prospective longitudinal study.

OBJECTIVES: The primary objective was to determine if the pain and function response to the McKenzie system of Mechanical Diagnosis and Therapy (MDT) differs by MDT classification category at two and four weeks following the start of MDT treatment for shoulder complaints. The secondary objective was to describe the frequency of discharge over time by MDT classification. METHODS: International, MDT-trained study collaborators recruited 93 patients attending physiotherapy for rehabilitation of a shoulder problem. The Numeric Pain Rating Scale (NPRS) and the Upper Extremity Functional Index (UEFI) were collected at the initial assessment and two and four weeks after treatment commenced. A two-way mixed model analysis of variance with planned pairwise comparisons was performed to identify where the differences between MDT classification groups actually existed. RESULTS: The Derangement and Spinal classifications had significantly lower NPRS scores than the Dysfunction group at week 2 and week 4 (p < 0.05). The Derangement and Spinal classifications had significantly higher UEFI scores than the Dysfunction group at week 2 and week 4 (p < 0.05). The frequency of discharge at week 2 was 37% for both Derangement and Spinal classifications, with no discharges for the Dysfunction classification at this time point. The frequency of discharge at week 4 was 83, 82 and 15% for the Derangement, Spinal and Dysfunction classifications, respectively. DISCUSSION: Classifying patients with shoulder pain using the MDT system can impact treatment outcomes and the frequency of discharge. When MDT-trained clinicians are allowed to match the intervention to a specific MDT classification, the outcome is aligned with the response expectation of the classification.Level of Evidence: 2b.

Inter-examiner reliability of diplomats in the mechanical diagnosis and therapy system in assessing patients with shoulder pain.

OBJECTIVE: To investigate the inter-examiner reliability of Mechanical Diagnosis and Therapy (MDT)-trained diplomats in classifying patients with shoulder disorders. The MDT system has demonstrated acceptable reliability when used in patients with spinal disorders; however, little is known about its utility when used for appendicular conditions. METHODS: Fifty-four clinical scenarios were created by a group of 11 MDT diploma holders based on their clinical experience with patients with shoulder pain. The vignettes were made anonymous, and their clinical diagnoses sections were left blank. The vignettes were sent to a second group of six international McKenzie Institute diploma holders who were asked to classify each vignette according to the MDT categories for upper extremity. Inter-examiner agreement was evaluated with kappa statistics. RESULTS: There was 'very good' agreement among the six MDT diplomats for classifying the McKenzie syndromes in patients with shoulder pain (kappa = 0.90, SE = 0.018). The raw overall level of multi-rater agreement among the six clinicians in classifying the vignettes was 96%. After accounting for the actual MDT category for each vignette, kappa and the raw overall level of agreement decreased negligibly (0.89 and 95%, respectively). DISCUSSION: Using clinical vignettes, the McKenzie system of MDT has very good reliability in classifying patients with shoulder pain. As an alternative, future reliability studies could use real patients instead of written vignettes.

Efficacy of exercise intervention as determined by the McKenzie System of Mechanical Diagnosis and Therapy for knee osteoarthritis: a randomized controlled trial.

STUDY DESIGN: Randomized controlled trial. Objectives To examine the efficacy of exercise intervention in patients with knee osteoarthritis (OA), as directed by Mechanical Diagnosis and Therapy (MDT) assessment, and, secondarily, to explore outcomes between MDT assessment-defined subgroups within the exercise group. BACKGROUND: Due to the high physical and economic burden of knee OA, the effectiveness of conservative interventions and determining those patients who will respond to them should be investigated. METHODS: Patients with knee OA (n = 180) were randomized to an exercise intervention group or a control group. The intervention group, in which patients classified as having knee derangements (MDT derangement) received MDT directional exercises and patients classified as nonresponders (MDT nonresponders) received evidence-based exercises, was compared to a control group that received no exercise intervention. Pain and function were assessed at baseline, 2 weeks, and 3 months, using the P4 pain scale and Knee injury and Osteoarthritis Outcome Score (KOOS) pain and function subscales. Two-way analysis of covariance was used to examine treatment and time effects. Multiple comparisons were examined, and mean differences with 95% confidence intervals (CIs) were reported. RESULTS: The exercise intervention group had significantly improved P4 scores (mean difference, -6; 95% CI: -8, -3), KOOS pain scores (mean difference, 9; 95% CI: 5, 13), and KOOS function scores (mean difference, 11; 95% CI: 7, 15) compared to those of the control group at 2 weeks. At 3 months, the exercise intervention group had significantly improved KOOS pain scores (mean difference, 7; 95% CI: 3, 11) and KOOS function scores (mean difference, 5; 95% CI: 1, 9) compared to controls. CONCLUSION: Patients with knee OA who were prescribed exercises based on an MDT assessment had superior outcomes compared to those of wait-list controls. The MDT subgroup of knee derangement may warrant further investigation in patients with knee OA. Protocol registered at ClinicalTrials.gov (NCT01641874). LEVEL OF EVIDENCE: Therapy, level 1b-.