Altered dynamic foot kinematics in people with medial knee osteoarthritis during walking: A cross-sectional study

BackgroundFootwear and insoles are used to reduce knee load in people with medial knee osteoarthritis (OA), despite a limited understanding of foot function in this group. The aim of this study was to investigate the differences in foot kinematics between adults with and without medial knee OA during barefoot walking.MethodsFoot kinematics were measured during walking in 30 adults; 15 with medial knee OA (mean age was 67.0 with a standard deviation (SD) of 8.9 years; height was 1.66 with SD of 0.13 m; body mass was 84.2 with SD of 15.8 kg; BMI was 30.7 with SD of 6.2 kg/m²; K–L grade 3: 5, grade 4: 10) and 15 aged and gender matched control participants with 12 motion analysis cameras using the IOR multi-segment foot model. Motion of the knee joint, hindfoot, midfoot, forefoot and hallux were compared between groups using clustered linear regression.ResultsThe knee OA group displayed reduced coronal plane range of motion of the midfoot (mean 3.8° vs. 5.4°, effect size = 1.1, p = 0.023), indicating reduced midfoot mobility. There was also a reduced sagittal plane range of motion at the hallux in the knee OA group compared to the control group (mean 29.6° vs. 36.3°, effect size = 1.2, p = 0.008). No statistically significant differences in hindfoot or forefoot motion were observed.ConclusionsPeople with medial knee OA display altered foot function compared to healthy controls. As foot and knee function are related, it is possible that altered foot function in people with knee OA may influence the effects of footwear and insoles.     

The relationship between pain and dynamic knee joint loading in knee osteoarthritis varies with radiographic disease severity. A cross sectional study

ObjectiveIn a cross sectional study, we investigated the relationships between knee pain and mechanical loading across the knee, as indicated by the external knee adduction moment (KAM) during walking in patients with symptomatic knee OA who were distinguished by different radiographic disease severities.MethodsData from 137 symptomatic medial knee OA patients were used. Based on Kellgren/Lawrence (K/L) grading, the patients were divided into radiographically less severe (K/L ≤ 2, n = 68) or severe (K/L > 2, n = 69) medial knee OA. Overall knee pain was rated on a 10 cm visual analog scale, and peak KAM and KAM impulses were obtained from gait analyses. Mixed linear regression analyses were performed with KAM variables as the outcome, and pain and disease severity as independent variables, adjusting for age, gender, and walking speed.ResultsIn adjusted analyses, less severe patients demonstrated negative relationships between pain intensities and dynamic loading. The severe patient group showed no relationship between pain intensity and peak KAM, and a positive relationship between pain intensity and KAM impulse.ConclusionIn radiographically less severe knee OA, the negative relationships between pain intensity and dynamic knee joint loading indicate a natural reaction to pain, which will limit the stress on the joint. In contrast, either absent or positive relationships between pain and dynamic loading in severe OA may lead to overuse and accelerated disease progression. These findings may have a large potential interest for strategies of treatment in knee OA.     

Knee joint preservation with combined neutralising high tibial osteotomy (HTO) and Matrix-induced Autologous Chondrocyte Implantation (MACI) in younger patients with medial knee osteoarthritis: a case series with prospective clinical and MRI follow-up over 5 years

PurposeThere is no ideal treatment for younger patients with medial knee osteoarthritis (OA) and varus malalignment. We have investigated the first case series of combined neutralising high tibial osteotomy (HTO) and Matrix-induced Autologous Chondrocyte Implantation (MACI) with MRI. Treatment goals were clinical improvement and delay of arthroplasty.MethodsBetween 2002 and 2005 18 patients (Mean age 47 years) underwent surgery. Exclusion criteria were lateral compartment and advanced patellofemoral OA. The Knee Injury and Osteoarthritis Outcome Score (KOOS), six minute walk test (6MWT) and a validated MRI score were outcome measures.ResultsThere were significant improvements (p < 0.05) in all five KOOS domains. Four were significantly maintained to 5 years. The domain “symptoms” and results in the 6MWT dropped off at 5 years. MRI results were first significantly improved (24/12) but declined at 60 months. Good quality infill was found in 33% patients at the study endpoint (n = 5/15). Histological investigation of one knee demonstrated full-thickness hyaline-like cartilage (20/12). After 2 early failures and one graft detachment graft fixation was changed (Smart nails instead of sutures in 14 cases). Graft hypertrophy requiring a chondroplasty occurred once. There were no other major complications. Specific minor complications included patellar tendinitis (n = 8).ConclusionsThis combined procedure provides a safe treatment option for younger patients with medial knee OA and varus alignment with significant clinical improvement at 5 years. However, overall graft survival and cartilage infill were poor. Larger studies are needed to statistically verify predictors for longer term cartilage repair in these patients.     

Abnormal tibiofemoral kinematics following ACL reconstruction are associated with early cartilage matrix degeneration measured by MRI T1rho

PurposeAltered kinematics following ACL-reconstruction may be a cause of post-traumatic osteoarthritis. T_1ρ MRI is a technique that detects early cartilage matrix degeneration. Our study aimed to evaluate kinematics following ACL-reconstruction, cartilage health (using T_1ρ MRI), and assess whether altered kinematics following ACL-reconstruction are associated with early cartilage degeneration.MethodsEleven patients (average age: 33 ± 9 years) underwent 3 T MRI 18 ± 5 months following ACL-reconstruction. Images were obtained at extension and 30° flexion under simulated loading (125 N). Tibial rotation (TR) and anterior tibial translation (ATT) between flexion and extension, and T_1ρ relaxation times of the knee cartilage were analyzed. Cartilage was divided into five compartments: medial and lateral femoral condyles (MFC/LFC), medial and lateral tibias (MT/LT), and patella. A sub-analysis of the femoral weight-bearing (wb) regions was also performed. Patients were categorized as having “abnormal” or “restored” ATT and TR, and T_1ρ percentage increase was compared between these two groups of patients.ResultsAs a group, there were no significant differences between ACL-reconstructed and contralateral knee kinematics, however, there were individual variations. T_1ρ relaxation times of the MFC and MFC-wb region were elevated (p ≤ 0.05) in the ACL-reconstructed knees compared to the uninjured contralateral knees. There were increases (p ≤ 0.05) in the MFC-wb, MT, patella and overall average cartilage T_1ρ values of the “abnormal” ATT group compared to “restored” ATT group. The percentage increase in the T_1ρ relaxation time in the MFC-wb cartilage approached significance (p = 0.08) in the “abnormal” versus “restored” TR patients.ConclusionsAbnormal kinematics following ACL-reconstruction appear to lead to cartilage degeneration, particularly in the medial compartment.     

Differences between opening versus closing high tibial osteotomy on clinical outcomes and gait analysis

BackgroundHigh tibial osteotomy (HTO) for medial knee osteoarthritis (OA) is mainly performed via two procedures: closing wedge HTO (CW) and opening wedge HTO (OW). In this study, differences between these procedures were assessed by serial clinical evaluation and gait analysis before and after surgery.MethodsTwenty-one patients underwent HTO for medial knee OA in 2011 and 2012, with 12 patients undergoing CW and nine undergoing OW. The severity of OA was classified according to the Kellgren–Lawrence classification. The Japanese Orthopedic Association score for assessment of knee OA (JOA score), the Numeric Rating Scale (NRS), and the femoral tibial angle (FTA) on X-ray were evaluated. For gait analysis, gait speed, varus moment, varus angle and lateral thrust were calculated.ResultsThe JOA score and NRS were improved significantly one year postoperatively in both groups. The FTA was maintained in both groups at one year. Varus angle and varus moment were significantly improved in both groups at each postoperative follow-up, when compared preoperatively. Lateral thrust was significantly improved at three months postoperatively in both groups. However, the significant improvement in lateral thrust had disappeared in the CW group six months postoperatively, whereas it was maintained for at least one year in the OW group.ConclusionsThis study found that clinical outcomes were well maintained after HTO. OW reduced knee varus moment and lateral thrust, whereas CW had little effect on reducing lateral thrust.Level of evidenceLevel IV     

Comparison the effect of lateral wedge insole and acupuncture in medial compartment knee osteoarthritis: A randomized controlled trial

BackgroundThere is lack of well-designed trials evaluating structural benefits of non-pharmacologic therapies in knee osteoarthritis (OA). In this parallel-group randomized controlled trial, we aim to compare the possible advantages of lateral wedge insole and acupuncture in patients with medial knee OA.MethodPatients with grade two or three of medial knee OA were randomly allocated to group one who received an in shoe lateral wedge and group two who underwent acupuncture. We assessed patients' pain, function and knee joint cartilage thickness before and after intervention. Paired t-test and independent samples t-test were used for in group and between group analyses. (Level of evidence: 2.)ResultsTwenty patients in each group were recruited in the study. Pain significantly decreased after therapy in both groups one and two (paired t test, P < 0.001, 95% CI: 1.62–3.25 and 1.58–3.20 respectively). Function improved in each group (paired t test, P = 0.001, 95% CI of 0.94–2.38 in group one and 0.97–2.43 in group two). A non-clinically statistically significant difference regarding the femoral and tibial cartilage thickness was obtained in both groups one (P = 0.005, CI: − 0.43–0.82 and P = 0.037, CI: − 0.44–0.80 respectively) and two (P = 0.025, CI: − 0.45–0.79 and P = 0.035, CI: − 0.29–0.96 respectively). Between groups analysis showed no significant difference regarding abovementioned measures.ConclusionBoth lateral wedge insole and acupuncture can be effective in the treatment of medial knee osteoarthritis without any superiority of one over the other.Iranian Registry of Clinical Trials: IRCT201201108235N1.URL: http://irct.ir/searchen.php     

A three dimensional approach for quantifying resultant loading at the knee

Background

Clinical effectiveness of lateral wedges for knee osteoarthritis is inconsistent across studies. One explanation is that knee loading is not fully described by the peak frontal-plane knee moment. The purpose of this study was to propose a 3D resultant approach to describing moments at the knee and evaluate how this moment changes in response to lateral wedges.

The effect of medial condylar bone loss of the knee on coronal plane stability--a cadaveric study

IntroductionThe quantitative effects of medial bone loss of the knee on both leg alignment and coronal plane stability are poorly understood.Materials and methodsUtilizing computer navigation, 5 mm bone defects of the medial distal femur (MDF), medial posterior femoral condyle (MPF), and medial tibial plateau (MT) were simulated in 10 cadaveric limbs, and alignment of the knee at various degrees of flexion were analyzed when applying standardized varus and valgus loads.ResultsThe 5 mm MPF defect significantly increased varus laxity at 90° of flexion by 3.3° ± 1.2° (p = 0.019), a 5 mm MDF defect resulted in a 2.2° ± 1.7° (p = 0.037) and a 2.1° ± 1.3° (p = 0.023) increase in laxity at 0° and 30° of flexion, respectively, and a 5 mm MT defect increased varus laxity at all flexion angles by 4.0° to 7.0°, but was only statistically significant at 30° (p = 0.026).DiscussionThis study confirms and quantifies the theories of flexion and extension gap balancing, and pseudolaxity of the medial collateral ligament in the varus knee, the results of which can be used in preoperative planning and intraoperative decision making for both total knee and unicondylar arthroplasty.     

A physiotherapist-delivered,combined exercise and pain coping skills training intervention for individuals with knee osteoarthritis: A pilot study

BackgroundOsteoarthritis (OA) of the knee is associated with a number of physical and psychological impairments. Unfortunately, very few treatment strategies are capable of addressing both types of impairments concurrently. We performed a pilot, randomized controlled, proof of principle trial investigating the feasibility and effects of an intervention combining physical exercise and pain coping skills training (PCST).MethodsTwenty patients with a clinical and radiographical diagnosis of tibiofemoral OA were randomized to receive either 10 weeks of physiotherapist supervised exercises (lower limb strengthening and walking) combined with non-directive counseling (NDC) or the same exercise program delivered concurrently with PCST. Primary outcomes included self-reported pain and pain coping, while secondary outcomes included self efficacy and self-reported physical function.ResultsTen participants were randomized to each group and both groups exhibited significant improvements in isometric knee strength, self-reported knee pain and physical function, self efficacy for control of pain management and other arthritis symptoms. Only those in the exercise + PCST group reported statistically significant improvements in pain control coping and rational thinking. No between-group differences existed in any outcome (0.07 < p < 0.98). Based on our findings, 63 participants per group would be needed for future large-scale studies using similar outcome measures and design.ConclusionsOur study showed that an intervention that combines exercise and PCST within the same treatment session and delivered by specially-trained physiotherapists is feasible and can improve both physical and psychological outcomes in individuals with knee OA.Level of evidenceLevel IIClinical Trials Registry number: ACTRN12609000623291     

A randomized double-blind clinical trial on the treatment of knee osteoarthritis: The efficacy of polynucleotides compared to standard hyaluronian viscosupplementation

BackgroundThis randomized, double-blind, parallel-group clinical trial aims to assess the equivalence of intra-articular polynucleotides compared to standard hyaluronic acid (HA) viscosupplementation in the treatment of knee osteoarthritis (OA).Methods75 patients affected by knee OA were assessed for eligibility and 72 were enrolled and randomized to receive either intra-articular polynucleotides (Condrotide-36 patients) or hyaluronic acid (Hyalubrix-36 patients) at the Orthopedic Institute “Gaetano Pini” (Milan).All patients underwent three intra-articular injections of Condrotide or Hyalubrix with an interval of 1 week. Participants, care givers, and investigators responsible for outcome assessment were all blinded to group assignment.Primary outcome measurements (KOOS and pain level (1)at rest, (2)at weight-bearing and (3) during physical activity) were evaluated at baseline (T0) and after one (T1), two (T2), six (T6), ten (T10), and 26 (T26) weeks.Secondary measurements included the determination of COMP serum levels at T0, T6 and T26.ResultsThe reduction of pain and the increase of KOOS values from baseline were statistically significant for both treatments; nevertheless, for parameter KOOS “symptoms” the treatment with Condrotide showed significant results already after two weeks (at T2 p = 0.003) while the results obtained with Hyalubrix became significant only after 18 weeks (at T18 p = 0.01).No significant adverse events were reported.ConclusionsCondrotide is as effective as Hyalubrix in reducing knee OA symptoms but showed an earlier response on pain reduction and can therefore be considered a valid alternative to the use of HA in the treatment of OA, avoiding the adverse events of NSAIDs and of intra-articular corticosteroids.     

Frontal plane knee mechanics and medial cartilage MR relaxation times in individuals with ACL reconstruction: A pilot study

BackgroundThe objective of this pilot study was to evaluate cartilage T_1ρ and T₂ relaxation times and knee mechanics during walking and drop-landing for individuals with anterior cruciate ligament reconstruction (ACL-R).MethodsNine patients (6 men and 3 women, age 35.8 ± 5.4 years, BMI 23.5 ± 2.5 kg/m²) participated 1.5 ± 0.8 years after single-bundle two-tunnel ACL reconstruction. Peak knee adduction moment (KAM), flexion moment (KFM), extension moment (KEM), and peak varus were calculated from kinematic and kinetic data obtained during walking and drop-landing tasks. T_1ρ and T₂ times were calculated for medial femur (MF), and medial tibia (MT) cartilage and compared between subjects with low KAM and high KAM. Biomechanical variables were compared between limbs.ResultsThe high KAM group had higher T_1ρ for MT (p = 0.01), central MT (p = 0.05), posterior MF (p = 0.04), posterior MT (p = 0.01); and higher T₂ for MT (p = 0.02), MF (p = 0.05), posterior MF (p = 0.002) and posterior MT (p = 0.01). During walking, ACL-R knees had greater flexion at initial contact (p = 0.04), and lower KEM (p = 0.02). During drop-landing, the ACL-R knees had lower KAM (p = 0.03) and KFM (p = 0.002).ConclusionPatients with ACL-R who have higher KAM during walking had elevated MR relaxation times in the medial knee compartments. These data suggest that those individuals who have undergone ACL-R and have higher frontal plane loading, may be at a greater risk of knee osteoarthritis.     

A quantitative assessment of varus thrust in patients with medial knee osteoarthritis

Varus thrust is an abnormal lateral knee motion frequently seen in patients with medial knee osteoarthritis (OA) during gait. It is a worsening of the alignment in the stance phase of the gait cycle and closely relates to disease progression. In this study, we measured the thrust quantitatively using skin markers and examined the relationship to other static and dynamic parameters. Forty-four knees in 32 patients (mean age, 72 years; range, 64–81 years) who exhibited the radiographic OA at least grade 2 according to the Kellgren–Lawrence (K–L) scale were enrolled. Gait analysis was performed for each patient to measure the amount of thrust and knee adduction moment. The amounts of thrust in subjects with K–L grades 2 (25 knees), 3 (13 knees), and 4 (6 knees) were 2.4°(± 1.3°), 2.8°(± 1.4°), and 7.2°(± 5.3°), respectively and the knee adduction moments were 3.6(± 1.5) %BW ? Ht, 3.9(± 1.2) %BW ? Ht and 6.9(± 2.2%) BW ? Ht, respectively. The amount of thrust also exhibited significant correlation to static radiographic alignment (R = 0.47: 95% confidence interval 0.67–0.21, p = 0.0038) and showed greater correlation to the knee adduction moment (R = 0.73: 95% confidence interval 0.84–0.55, p < 0.001), which has been identified as an important dynamic index of the disease. The amount of thrust, which is able to be measured by simple inexpensive equipment, correlated to static and dynamic parameters and may offer an important clinical index for knee OA.     

Effect of lower limb malalignment in the frontal plane on transverse plane mechanics during gait in young individuals with varus knee alignment

BackgroundVarus knee alignment has been identified as a risk factor for the progression of medial knee osteoarthritis (OA). This study tested the hypothesis that not only frontal plane kinematics and kinetics but also transverse plane lower extremity mechanics during gait are affected by varus malalignment of the knee.MethodsEighteen, otherwise healthy children and adolescents with varus malalignment of the knee were studied to examine the association between static varus malalignment and functional gait parameters. Kinematic data were collected using a Vicon motion capture system (Vicon Motion Systems, Oxford, UK). Two AMTI force plates (Advanced Mechanical Technology, Inc., Watertown, MA, USA) were used to collect kinetic data.ResultsThe results indicated that changes in transverse plane mechanics occur concomitantly with changes in knee malalignment in the frontal plane. A mechanical consequence of varus knee malalignment is obviously an increased endorotation of the foot (internal foot placement) and an increased internal knee rotation (tibia rotation) during stance phase. The linear correlation between the maximum external knee adduction moment in terminal stance and the internal knee rotation in terminal stance (r = 0.823, p < 0.001) shows that this transverse plane gait mechanics is directly in conjunction with intrinsic compressive load on the medial compartment during gait.ConclusionsUnderstanding factors that influence dynamic knee joint loading in healthy, varus malaligned knees may help us to identify risk factors that lead to OA. Thus, three-dimensional gait analysis could be used for clinical prognoses regarding the onset or progression of medial knee OA.     

Cadaveric results of an accelerometer based, extramedullary navigation system for the tibial resection in total knee arthroplasty

IntroductionIn total knee arthroplasty, the accuracy and precision of the tibial resection must be improved. The purpose of this study was to determine the accuracy and time associated with the use of an accelerometer based, extramedullary surgical navigation system for performing the tibial resection.Materials and methodsFour orthopedic surgeons performed a tibial resection utilizing the KneeAlign? system, each on five separate, cadaveric tibiae. Each surgeon was assigned a preoperative “target” of varus/valgus alignment and posterior slope prior to each resection. The alignment of each resection was measured using both plain radiographs and computed tomography, along with the time required to use the device.ResultsRegarding coronal alignment, the mean absolute difference between the preoperative “target” and tibial resection alignment was 0.77° ± 0.64° using plain radiograph, and 0.68° ± 0.46° using CT scan measurements. Regarding the posterior slope, the mean absolute difference between the preoperative “target” and the tibial resection was 1.06° ± 0.59° using plain radiograph, and 0.70° ± 0.47° using CT scan measurements. The time to use the KneeAlign? for the fifth specimen was less than 300 s for all four orthopedic surgeons in this study.DiscussionThis cadaveric study demonstrates that the KneeAlign? system is able to accurately align the tibial resection in both the coronal and sagittal planes.Level of evidenceCadaveric study.     

Effect of walking with a modified gait on activation patterns of the knee spanning muscles in people with medial knee osteoarthritis

ObjectiveTo evaluate muscle activation patterns and co-contraction around the knee in response to walking with modified gait patterns in patients with medial compartment knee-osteoarthritis (KOA).Design40 medial KOA patients walked on an instrumented treadmill. Surface EMG activity from seven knee-spanning muscles (gastrocnemius, hamstrings, quadriceps), kinematics, and ground reaction forces were recorded. Patients received real-time visual feedback on target kinematics to modify their gait pattern towards three different gait modifications: Toe-in, Wider steps, Medial Thrust. The individualized feedback aimed to reduce their first peak knee adduction moment (KAM) by ≥ 10%. Changes in muscle activations and medial/lateral co-contraction index during the loading response phase (10–35% of the gait cycle) were evaluated, for the steps in which ≥ 10% KAM reduction was achieved.ResultsData from 30 patients were included in the analyses; i.e. all who could successfully reduce their KAM in a sufficient number of steps by ≥ 10%. When walking with ≥ 10% KAM reduction, Medial Thrust gait (KAM − 31%) showed increased flexor activation (24%), co-contraction (17%) and knee flexion moment (35%). Isolated wider-step gait also reduced the KAM (− 26%), but to a smaller extent, but without increasing muscle activation amplitudes and co-contraction. Toe-in gait showed the greatest reduction in the KAM (− 35%), but was accompanied by an increased flexor activation of 42% and hence an increased co-contraction index.ConclusionGait modifications that are most effective in reducing the KAM also yield an increase in co-contraction, thereby compromising at least part of the effects on net knee load.     

Quadriceps strength is not related to gait impact loading in knee osteoarthritis

Joint loading has been implicated in the pathogenesis of knee osteoarthritis (OA). While compartment-specific measures such as the knee adduction moment have received much attention in the literature, less is known about other measures of dynamic loading in this patient population. This cross-sectional study assessed strength and walking patterns of 204 individuals with radiographically confirmed medial tibiofemoral OA and varus malalignment. Pearson product moment correlations and regression analyses were used to determine the bivariate and multivariate relationships amongst measures of impact loading (rate of loading and heelstrike transient occurrence) with demographic, clinical (in particular, radiographic disease severity, lower limb alignment, and self-reported pain and function), and biomechanical variables (maximum voluntary isometric quadriceps strength and gait kinematics). While maximum voluntary isometric quadriceps strength was significantly correlated with rate of loading (r > 0.27) when walking at a freely chosen speed, multiple regression analyses indicated that rate of loading was primarily dictated by walking speed (p < 0.001), and the effect of quadriceps strength was insignificant when accounting for all other included variables. Individuals who exhibited a heelstrike transient in their vertical ground reaction force profile were significantly more varus malaligned and were more likely to demonstrate severe radiographic degeneration than those who did not exhibit heelstrike transients. These results demonstrate higher impact loading during walking in those with knee OA with faster self-selected walking speeds, though the relationship with quadriceps strength is less clear. Importantly a potential association between disease characteristics, such as malalignment and disease severity, and higher impact loading was also observed.     

Effects of a knee valgus unloader brace on medial femoral articular cartilage deformation following walking in varus-aligned individuals

BackgroundKnee varus alignment may increase loading in the medial tibiofemoral compartment, which can increase strain on the articular cartilage. Knee valgus unloader braces seek to reduce loading through the medial femoral compartment, but their effects on cartilage characteristics during dynamic tasks have not been evaluated.ObjectiveTo determine the effects of a knee valgus unloader brace on medial femoral articular cartilage deformation following a single 5000-step walking protocol in individuals with varus-knee alignment.MethodsTwenty-four healthy individuals (63% female, BMI = 22 ± 3 kg/m², age = 21 ± 3 years) completed two testing sessions (braced and unbraced) separated by one week. During both sessions, femoral cartilage ultrasound images were acquired prior to and following a 5000-step treadmill walking protocol at self-selected speed. Percent change scores in medial cartilage cross-sectional area (MCCA) were calculated and used as the primary outcome, and compared between the braced and unbraced conditions.ResultsThere was no difference in percent change of MCCA between conditions (braced = − 2.77%, unbraced = − 3.15%, p = 0.699). Individuals whose cartilage deformed more than a previously established minimal detectable change (MDC ≥ 1.58 mm²) deformed less during the braced condition (braced = − 2.94%, unbraced = − 6.34%, p = 0.028), compared to individuals who did not deform greater than the MDC (n = 15, braced = − 2.67%, unbraced = − 1.23%, p = 0.210).ConclusionsThere was no significant difference in MCCA percent change between the braced and unbraced conditions across the entire cohort; yet a valgus unloader braces may serve as a potential intervention strategy for reducing articular cartilage deformation in certain varus-aligned individuals who normally undergo measurable deformation during walking.     

Efficacy of passive extension mobilization in addition to exercise in the osteoarthritic knee: An observational parallel-group study

Study designPretest post-test observational parallel-group design.ObjectivesTo evaluate the efficacy of passive knee extension mobilization in addition to exercise therapy on extension range of motion (ROM) in patients with osteoarthritis (OA) of the knee. Secondary objectives were to determine changes in pain and functional abilities.BackgroundPatients with knee OA complain of pain, limited range of motion, and impaired activities. Efficacy of mobilization as a treatment option next to exercises has not been studied rigorously.Methods and measuresThirty-four participants with persistent knee pain, a positive radiography for knee OA, and a passive extension deficit were included. Seventeen participants (mean age ± SD, 59.8 ± 6.1 years) were treated with an exercise protocol and were additionally given manual mobilizations to improve passive extension ROM. The other group (mean age ± SD, 61.5 ± 7.3 years) with equal characteristics was treated with an identical exercise therapy protocol only. Prior to participation, detailed ROM measurements were recorded next to muscle function tests, pain (VAS), six-minute walking tests (6MWTs), a condition-specific questionnaire, and the patient-specific function scale (PSFS). Participants in both groups completed 16 treatment sessions each.ResultsPassive mobilization significantly improved extension ROM in the intervention group (5.2 versus 8.6°, p = .017). The manually mobilized group also had better physical capacities as assessed by 6MWT, less pain, and a lower PSFS score.ConclusionA combined protocol including exercise therapy and passive mobilization was beneficial for patients with OA of the knee complaining of pain, decreased extension ROM and decreased limited abilities.Level of evidenceTherapy, 2b.     

Walking shoes and laterally wedged orthoses in the clinical management of medial tibiofemoral osteoarthritis: A one-year prospective controlled trial

The purpose of the study was to examine the clinical efficacy of individually prescribed laterally wedged orthoses and walking shoes in the treatment of medial knee osteoarthritis using a prospective, single-blind, block-randomized controlled design.Sixty-six subjects (29 males, 37 females, mean age 62.4 years, mean BMI 33.0 kg/m²) were block-randomized to a lateral wedge (treatment) or neutral (control) orthotic group. Both groups were issued a standardized walking shoe for use with the orthoses. Primary outcome measures included the pain, stiffness, and functional limitations subscales of the Western Ontario and McMaster Universities index. Secondary outcome measures included the 6-minute walk distance and pain change, and stair negotiation time and pain change.A significant interaction (p = 0.039) favoring the treatment group was observed for pain change during the 6-minute walk. The treatment group demonstrated significant improvements at both 1 month (p < 0.001) and 1 year (p < 0.001) compared to baseline. The control group only demonstrated significant improvements at 1 year (p = 0.017). No other interactions were observed. Both groups were improved at each follow-up in the WOMAC subscales for pain (p < 0.001), stiffness (p < 0.001), and physical function (p < 0.001). Both groups also improved in 6-minute walk test distance (p < 0.001), stair negotiation test time (p = 0.004), and stair negotiation test pain change (p < 0.001).The results suggest that both neutral and laterally wedged orthoses may be beneficial in the management of medial knee osteoarthritis when used with walking shoes. However, the addition of lateral wedging was associated with early improvements in 6-minute walk test pain change not seen in the control group.     

Survivorship of UKA in the middle-aged

BackgroundUnicompartmental knee arthroplasty (UKA) is known to be a viable procedure allowing for preservation of the intact compartments and delivering excellent function at long-term follow-up. The primary purpose of this single-surgeon study was to analyse the survivorship of a fixed bearing UKA in patients younger than 60 years.MethodsFrom all UKAs implanted between 1993 and 2005 at the senior authors' centre, 223 patients < 60 years at operation with a minimum follow-up of 5 years were identified including all-poly and metal-backed tibiae. They were evaluated applying the Knee Society Score (KSS) at latest follow-up. Survivorship was calculated using Kaplan–Meier analysis, which considered the following variables: gender, type of tibial implant, medial vs. lateral UKA, and age.ResultsAverage age at index operation was mean 53.7 (SD 5.8, range 30–60) years at a mean follow-up of 10.8 (SD 3.5, range 5–17) years. From the KSS, the knee score was 94.3 (SD 7.8) and the function score was 94.9 (SD 6.8). At latest follow-up, the implant survival rate was 94.3%. Survivorship for the entire cohort was 93.5% at 10 years (medial UKA 94.1% vs. lateral 91.8%), and 86.3% at 15 years (85.1% medial vs. 91.7% lateral)ConclusionIn conclusion, excellent survival and function outcomes were noted in this subgroup of patients younger than 60 years. Revision rates were comparable to those studies in which UKA was performed on an elderly patient population. UKA can successfully be performed in patients younger than 60 years with appropriate patient selection.