Longitudinal changes in knee kinematics and moments following knee arthroplasty: A systematic review

The Knee 21 (2014) 994–1008

Contents lists available at ScienceDirect

The Knee

Review

Longitudinal changes in knee kinematics and moments following knee arthroplasty: A systematic review L. Sosdian a,1, F. Dobson a,1, T.V. Wrigley a,1, K. Paterson a,1, K. Bennell a,1, M. Dowsey b,2, P. Choong b,2, K. Allison a,1, R.S. Hinman a,⁎ a b

Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC Australia The University of Melbourne, Department of Surgery, St Vincent’s Hospital, Melbourne, Australia

a r t i c l e

i n f o

Article history: Received 7 July 2014 Accepted 17 September 2014 Keywords: Knee replacement Biomechanics Systematic review Osteoarthritis

a b s t r a c t Background: Knee arthroplasty (KA) is recognized as an effective treatment of knee joint osteoarthritis and up to 90% of patients experience substantial pain relief. There has been no systematic review synthesizing the longitudinal changes in gait following KA. The aims of this systematic review were to determine the effects of KA on (i) frontal plane and (ii) sagittal plane kinematic and kinetic parameters during the stance phase of gait. Methods: MEDLINE (PubMed), CINAHL, SPORTdiscus (EBSCO), and Cochrane Library (Wiley) were searched until April 10th, 2014. 1,765 articles were identified, of which 19 studies describing 3-dimensional gait analysis preand post-KA were included. Study quality was evaluated by two reviewers independently using the Downs and Black checklist. Findings: Following KA, in the frontal plane, the maximum knee adduction angle and external knee adduction moment (KAM) tended to decrease. In the sagittal plane, findings suggest that the maximum knee flexion moment is increased. From the ten studies that included a healthy reference group, it was unclear whether gait variables returned to normal following KA. Interpretation: Overall, it appears that KA results in a decreased peak KAM and maximum knee adduction angles, an increased peak knee flexion moment and inconsistent changes in the peak knee flexion angle. Knowledge gaps remain due to methodological inconsistencies across studies, limited statistical analysis, and largely heterogeneous sample populations. More research is needed to determine whether KA restores gait patterns to normal, or if additional rehabilitation may be needed to optimize gait following surgery for osteoarthritis. © 2014 Elsevier B.V. All rights reserved.

Contents 1. 2.

3.

Introduction . . . . . . . . . . . . . . . . . . . Search strategy and criteria . . . . . . . . . . . . 2.1. Eligibility . . . . . . . . . . . . . . . . . 2.2. Data extraction . . . . . . . . . . . . . . 2.3. Quality evaluation . . . . . . . . . . . . . 2.4. Data analysis . . . . . . . . . . . . . . . Results . . . . . . . . . . . . . . . . . . . . . 3.1. Study characteristics . . . . . . . . . . . . 3.2. Frontal plane . . . . . . . . . . . . . . . 3.3. Sagittal plane . . . . . . . . . . . . . . . 3.4. Comparison to control group, where available 3.5. Quality evaluation . . . . . . . . . . . . .

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⁎ Corresponding author at: Level 7, Alan Gilbert Building, Building 104, The University of Melbourne, Vic, 3010, Melbourne, Australia. Tel.: +61 3 8344 3223. E-mail addresses: [email protected] (L. Sosdian), [email protected] (F. Dobson), [email protected] (T.V. Wrigley), [email protected] (K. Paterson), [email protected] (K. Bennell), [email protected] (M. Dowsey), [email protected] (P. Choong), [email protected] (K. Allison), [email protected] (R.S. Hinman). 1 Postal Address: Level 7, Alan Gilbert Building, Building 104, The University of Melbourne, Vic, 3010, Melbourne, Australia. 2 Postal Address: Level 2, Clinical Sciences Building, 29 Regent Street, Fitzroy 3065, Victoria, Australia.

http://dx.doi.org/10.1016/j.knee.2014.09.009 0968-0160/© 2014 Elsevier B.V. All rights reserved.

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L. Sosdian et al. / The Knee 21 (2014) 994–1008

4. Discussion . Financial support Conflict of Interest References . . .

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1. Introduction First popularized in the 1970s [1], knee arthroplasty (KA) is recognized as an effective treatment of advanced knee joint osteoarthritis (OA). Gait abnormalities and increased joint loading are associated with knee OA [2–4], and often increase as disease severity and knee pain worsen over time. In particular, frontal plane abnormalities in

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1006 1007 1007 1007

kinematics (joint motion) and kinetics (joint moments) are of importance in knee OA as they have been linked to disease progression [5–7]. These abnormalities include: higher external knee adduction moment (KAM) [8–10] and KAM impulse [11], as well as an increased incidence of abnormal varus-valgus motion [6] when compared to those without OA. Persistent abnormal gait biomechanics following KA may contribute to sub-optimal clinical outcomes from the procedure

Fig. 1. A flow chart of the study selection process.

996

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Table 1 Description of included studies. Author, year

TKR Population (preoperative)

Evaluation Time Points

Loss to Follow-Up

Gait Domains Assessed

Healthy Reference Group

Abdel, Matthew P. 2014

n = 40

pre-operative

Not reported

kinematics, moments

NI

Age: 71

3 months postoperative

Not reported

kinematics, moments

n=8

Urwin, Samuel, G. 2013

40% M 60% F BMI: 29.15 recruited from the surgical waiting list n = 16 Age: 59.5

Worsley, P. 2013

63% M 37% F BMI: 31.9 recruitment not reported n = 34 Age: 64 (10)

pre-operative 9 months postoperative

Age: 60.5 (7) 63% M 37% F BMI: 20.06 (1.21)

pre-operative 6 months postoperative

Not reported

moments

59% F 41%M BMI: 31 (6) recruitment not reported Vahtrik, D. 2013

Levinger, P. 2013

n = 13 Age: 60 (7.7) 100% F BMI: 33 (4.4) recruited from the surgical waiting list n = 32 Age: 68.3 (6.4)

Metcalfe, Andrew 2013

Wegrzyn, J. 2012

45% F 54% M BMI 30.4 (5.1) recruited from 2 different medical centres n = 14 Age: 68.9

38% F 62% M BMI: 30.5 recruitment not reported n = 24 Age: 66

Orishimo, K. F. 2012

100% F BMI: 29.3 recruitment not reported n = 15 Age: 65

Levinger, P. 2012

54% F 47% M BMI: 28.7 recruitment not reported n = 32 Age: 68 (6.4)

Tibesku, C. O. 2011

44% F 56% M BMI: 30.4 (5.0) recruited from 2 different medical centres n = 33

Not reported

moments

55% F 45% M BMI: 28 (4) recruited from the local community n = 10 Age: 47-70 years 100% F BMI: 27-38

pre-operative

Nil

kinematics, moments

12 months postoperative

pre-operative 12 months postoperative

64% F 36% M BMI: 31.0 (3.9) recruited from 2 local hospitals n = 37 pre-operative Age: 65.5

Thomsen, M. G. 2012

pre-operative 3, 6 months postoperative

n = 20 Age: 62 (6)

n = 28 Age: 65.1 (11.2)

Nil

moments

54%F 46%M BMI: 25.3 (4.5) recruited from retirement villages n = 20 Age: 68.3 50% F 50% M BMI: 26.3 (3.6)

1

kinematics, moments

NI

6

kinematics, moments

NI

Not reported

kinematics, moments

NI

Not reported

kinematics, moments

NI

Not reported

kinematics, moments

NI

2 months postoperative

pre-operative 12 months postoperative

pre-operative 6, 12 months postoperative

pre-operative 4, 12 months postoperative

pre-operative

L. Sosdian et al. / The Knee 21 (2014) 994–1008

997

Table 1 (continued) Author, year

Chang, Q. Z. 2011

Bejek, Z. 2011

TKR Population (preoperative)

Evaluation Time Points

Age: 65.5

24 months postoperative

64% F 36% M recruitment not reported n = 25 Age: 73.96 (6.27) 84% F 16% M recruited from 1 hospital n = 45 Age: 68.3

51% F 49% M BMI: 26.8 recruitment not reported Apostolopoulos, A. 2011 n = 20 Age: 69.6 (6.6)

Xu, Y-M 2010

60% F 40% M BMI: 31.226 (5.22) recruitment not reported n = 52 Age: 66.5

Mandeville, D. 2008

60% F 40% M BMI: 22.43 recruitment not reported n = 21 Age: 62.80 (1.65)

Liebensteiner, M. C. 2008

BMI: 32.9 (1.12) recruitment not reported n = 30 Age: 72

Mandeville, D. 2007

BMI: 27.5 recruitment not reported n = 21 Age: 62.60

Smith, A. J. 2003

76% F 24% M BMI: 32.60 (1.08) recruitment not reported n = 43 Age: 69 (7)

Loss to Follow-Up

Gait Domains Assessed

Healthy Reference Group

pre-operative 1 month postoperative

Not reported

kinematics

NI

pre-operative 3, 6, 9, 12 months post-operative

Not reported

kinematics

n = 21 Age: 76 57% F 43% M BMI: 26.8

pre-operative

Nil

kinematics, moments

NI

1

kinematics, moments

n = 20

9 months postoperative

pre-operative 3, 12 months postoperative

pre-operative

Age, height and weight matched to each patient

Not reported

kinematics, moments

6 months postoperative

n = 21 Age: 62.85 (0.90) BMI: 26.60 (0.73)

pre-operative

pre- and post-op gait data available for 20 patients

kinematics

NI

1

kinematics, moments

n = 21

3 months postoperative

pre-operative 6 months postoperative

Age: 62.70 (0.90) 62% F 38% M BMI: 26.6

pre-operative

pre- and post-op gait data available for 34 patients

12-18 months postoperative

50% F 50% M BMI: 30.5 (5.8) recruited from 2 university teaching hospitals

kinematics, moments

n = 20 Age: 67 (7) 50% F 50% M BMI: 24.9 (2.9)

Legend. NI = not included; F = female, M = male, BMI = body mass index

(such as ongoing knee pain and/or functional limitations) [12–14], patient dissatisfaction and/or prosthesis failure over the long-term. To date, most gait analysis research following KA has tended to focus on the sagittal plane. Before KA, individuals with severe OA have been shown to walk with sagittal plane moments different to controls [4,15]. The presence of an abnormal pre- and postoperative peak flexion moment have been associated with a higher risk of tibial component loosening [16] and the presence of anterior knee pain [12], making the case for the importance of correcting gait patterns with surgery. Although two systematic reviews [17, 18] have cross-sectionally compared post-operative sagittal plane biomechanics to those of healthy control groups, no review has synthesized the literature evaluating longitudinal changes in the sagittal plane parameters in those who undergo a KA procedure.

An understanding of how KA changes frontal plane gait biomechanics is also important. KA aims to improve the tibiofemoral loading environment, particularly by reducing the frontal plane malalignment that typically accompanies knee OA. Static knee malalignment (as measured on xray) is linked to changes in joint loading [19], and varus malalignment (most commonly observed in medial OA) directly increases parameters of the KAM, a biomechanical indicator of medial compartment load distributions [20]. Furthermore, during gait, abnormal dynamic knee varus-valgus motion can occur. This dynamic malalignment is a separate phenomenon from static knee malalignment and acutely influences load across the medial tibiofemoral compartment. Presence of this excessive varus-valgus motion after surgery could have implications for abnormal knee joint loading.

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Table 2 Changes in frontal plane kinematics following knee arthroplasty. Surgical Detail

Variable Measured

Pre-op KA

Post-op KA

p-value: within KA group comparison

Effect sizes (95% confidence interval)

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

Apostolopoulos, 2011 Mandeville, 2008 Apostolopoulos, 2011 Apostolopoulos, 2011 Urwin, 2013

PCL retaining total knee prosthesis

Abduction knee angle first touch Mean abduction knee angle at 1st peak GRF Abduction knee angle mid stance Abduction knee angle late stance Max adduction angle

3.17 (6.87) -1.87 (1.38) -0.62 (10.49) 0.71 (9.10) 8.39 (13.53) 5.34 (11.70) 5.50 (4.59) 8.50 (4.32) 9.7 (6.5) 9.8

9.62 (5.04) -5.81 (0.89) 5.98 (4.51) 6.91 (5.05) 1.82 (11.93) -1.64 (4.89) 2.50 (2.17) 2.50 (2.07) 5.2 (7.6) 6.3

0.003

-1.06 (-1.72, -0.40)

NI

NA

p b 0.0125

3.41 (2.46, 4.35)

-5.46 (0.89)

NR

p b 0.001

-0.86 (-1.51, -0.21)

NI

NA

0.349

-0.86 (-1.51, -0.21)

NI

NA

NA

0.50 (-0.20, 1.21)

7.41 (5.83)

0.59

NA

0.82 (0.10, 1.54)

7.41 (5.83)

0.13

NR

0.88 (0.48, 1.28)

2.34 (1.28)

NA

p b 0.05

1.86 (1.40, 2.32)

2.34 (1.28)

NA

0.001

0.62 (-0.11, 1.35)

NI

NA

0.03

no standard deviation no standard deviation 1.06 (0.57, 1.55)

NI

NA

NI

NA

NI

NA

NI

NA

NI

NA

NI

NA

Xu, 2010

Orishimo, 2012 Abdel, 2014

Wegzryn, 2012 Abdel, 2014

Wegzryn, 2012 Urwin, 2013

Xu, 2010

Urwin, 2013

Posterior stabilized total knee prosthesis PCL retaining total knee prosthesis PCL retaining total knee prosthesis Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Patella resurfacing

Max adduction angle Max adduction angle

Patella nonresurfacing

Max adduction angle

Posterior-stabilized TKR

Max adduction angle #

Patient-specific instrumentation

Knee adduction angle

#

Conventional instrumentation

Knee adduction angle

9.25

6

0.07

Cemented tricompartmental posterior-stabilised prosthesis with mobile bearingH mini-subvastus approach Patient-specific instrumentation

Knee adduction angle

8.02 (3.52) -8

3.88 (4.21) -4.5

0.005 0.2

#

Knee abduction angle

Conventional instrumentation

Knee abduction angle

-7.95

-5.8

NA

Cemented tricompartmental posterior-stabilised prosthesis with mobile bearingH mini-subvastus approach Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Patella resurfacing

Knee abduction angle

NA

0.53 (-0.17, 1.24)

-7.11 (7.58)

NR

NA

0.87 (0.15, 1.60)

-7.11 (7.58)

NR

NA

0.13 (-0.26, 0.51)

25.41(8.64)

NA

Max abduction angle

NA

0.27 (0.11, 0.66)

25.41(8.64)

NA

Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK

Frontal knee ROM

5.66 (3.10) -13.94 (12.94) -11.08 (6.57) 27.16 (10.72) 27.67 (9.29) 15.77 (7.03) 9.43 (2.22)

p b 0.0001

Patella nonresurfacing

1.58 (3.06) -6.53 (14.09) -3.53 (10.34) 28.83 (14.91) 30.83 (13.54) 14.92 (4.02) 8.87 (4.82)

no standard deviation no standard deviation -1.31 (-1.82, -0.80)

NA

-0.15 (-0.84, 0.54)

14.52 (3.39)

1

NA

-0.16 (-0.85, 0.54)

14.52 (3.39)

0.14

*flexor moment pattern **biphasic moment pattern post-op measurements taken from last time point reported # measure of variability other than standard deviation reported

#

Max knee abduction angle Max knee abduction angle Max abduction angle

Frontal knee ROM

A = Stryker, USA B = ASDM, Australia C = Smith & Nephew, Germany D = Zimmer E = Smith & Nephew Richards Inc, Memphis, TN F = Kinemax, Stryker, Kalamazoo, Michigan G = W. Link Gmbh and Co., Germany H = Sigma RP knee system; DePuy Orthopaedics, Inc, Warsaw, IN, USA

IC = initial contact ROM = range of motion TKR = total knee replacement GRF = ground reaction force KAM = knee adduction moment PCL = posterior cruciate ligament

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Author

NA= not statistically analysed NR= analysed, p-value not reported NI = not included

L. Sosdian et al. / The Knee 21 (2014) 994–1008

a) maximum knee adduction angle

999

b) peak knee adduction moment Tibesku, 2011 mobile-bearing

Orishimo, 2012

Tibesku, 2011 fixed-bearing Xu, 2010 patella resurfacing

Thomsen, 2012 LPS-flex Thomsen, 2012 high-flex

Xu, 2010 patella nonresurfacing

Urwin, 2014 fixed-bearing Urwin, 2014 mobile-bearing

Urwin, 2014 fixed-bearing

Worsely, 2013 Urwin, 2014 mobile-bearing

-0.5

0

0.5

1

1.5

2

2.5

Metcalfe, 2013

-1

c) maximum knee flexion angle

-0.5

0

0.5

1

1.5

2

2.5

d) peak knee flexion moment Xu, 2010 patella nonresurfacing Xu, 2010 patella resurfacing Thomsen, 2012 LPS-flex Thomsen, 2012 high-flex Tibesku, 2011 mobile-bearing Tibesku, 2011 fixed-bearing Urwin, 2014 mobile-bearing Urwin, 2014 fixed-bearing Worsley, 2013 Vahtrik, 2013 Levinger, 2013

Tibesku, 2011 mobile-bearing Tibesku, 2011 fixed-bearing Levinger, 2012 biphasic moment Levinger, 2012 flexor moment Xu, 2010 patella nonresurfacing Xu, 2010 patella resurfacing Thomsen, 2012 LPS-flex Thomsen, 2012 high-flex Urwin, 2014 fixed-bearing Urwin, 2014 mobile-bearing Levinger, 2013 -3

-2

-1

0

1

2

-2

-1.5

-1

-0.5

0

0.5

1

Fig. 2. Graphical representation of the effect sizes for selected variables (a. maximum knee adduction angle b. peak knee adduction moment c. maximum knee flexion angle d. peak knee flexion moment) following knee arthroplasty. Negative effect size values indicate an increase in the value at the post-operative time point, whereas positive effect size values indicate a decrease in the value at the post-operative time point. The vertical line at zero indicates a line of no effect.

Both pre- and post-operative alignment have been shown to be important in total load in the knee joint [21] and implant survival rates [22]. Given that a major aim of KA is to mechanically correct knee malalignment and optimize joint loading, an understanding of the effects of arthroplasty on frontal plane gait biomechanics is relevant. Implant retrieval studies have suggested that medial compartment rather than lateral compartment wear is dominant after surgery, suggesting that pre-operative abnormal loading conditions may not have been corrected, or may have returned at some point post-operatively [23–25]. Although two systematic reviews have compared postarthroplasty gait to that of healthy controls [17,18], they did not synthesize evidence regarding longitudinal changes in frontal plane biomechanics with KA, and several gait studies have since been published in the six years since the literature search of Milner was conducted. The purpose of this systematic review was to synthesize longitudinal biomechanical studies evaluating changes in 3-dimensional gait analysis following KA. The primary aim was to assess the effects of KA procedures on the frontal plane kinematics and kinetics in stance phase of gait. Secondary aims were to evaluate changes in the sagittal plane parameters, and to compare frontal and sagittal post-operative gait parameters to those of a healthy reference group. 2. Search strategy and criteria The search strategy was developed, reviewed, and refined by multiple authors with expertise in systematic reviews, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines [26]. Electronic searches of entire databases up until April 10th, 2014 were performed using MEDLINE (PubMed), CINAHL and SPORTdiscus (EBSCO), and Cochrane Library (Wiley). Key search terms and synonyms were searched separately in three main filters which were then combined. These filters are summarized as: ("arthroplasty, replacement, knee" [MeSH]) OR TKA[tw]) OR TKR[tw]) AND (postop* OR postoperative* OR "postoperative period"[MeSH: NoExp] OR "cross-sectional studies"[MeSH] OR randomized controlled

trial OR RCT OR "case-control studies"[MeSH Terms] OR preoperative* OR change* OR post-surg* OR pre-surg* OR post-TKA OR post-TKR OR comparison*) AND (kinetics OR kinematics OR load OR joint angle OR moment OR force OR 3D gait analysis OR biomechanics OR mechanics OR torque OR gait OR KAM OR “spatiotemporal” [MeSH]). Supplementary searches of the reference lists of potentially eligible studies were conducted, in conjunction with the use of the “cited by” option in Scopus to identify additional studies.

2.1. Eligibility Eligibility was determined by two reviewers independently (LS and KA), with discrepancies resolved by consensus. Following removal of duplicates, titles and abstracts were initially screened. Full texts of potentially suitable studies were assessed for eligibility. Biomechanical studies describing three-dimensional gait analysis of patients pre- and post-operatively following KA were included. All study designs were eligible provided that three-dimensional motion analysis during unaided, level walking was used to evaluate gait. Studies were required to report knee kinematics or joint moments in the frontal or sagittal planes. Only studies from which data could be extracted as a point estimate (e.g. mean) with a measure of variability (e.g. standard deviation, SD or confidence interval, CI) were eligible. Studies repeating gait data from a previous study, or reported only in abstract form, dissertation or non-English, or those investigating only arthroplasty revision procedures were excluded.

2.2. Data extraction One reviewer (LS) extracted the following information: participant characteristics at the pre-operative time point, relevant surgical information (e.g. prosthesis type), duration between pre- and post-surgical evaluation, characteristics of the healthy reference group (if included), and information about loss to follow-up. Where participant

1000

Table 3 Changes in frontal plane moments following knee arthroplasty. Surgical detail

Variable measured

Pre-op KA

Post-op KA

p-value: within KA comparison

Effect sizes [95% confidence interval]

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

Apostolopoulos, 2011 Metcalfe, 2013 Orishimo, 2012

PCL retaining total knee prosthesis Not described Posterior-stabilized TKR Posterior-stabilized TKR Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Unilateral (The Oxford, Biomet Orthopaedics), Total (P.F.C. Sigma, Depuy, Johnson and Johnson) Not described Patient-specific instrumentation\ Conventional instrumentation Unilateral (The Oxford, Biomet Orthopaedics), Total (P.F.C. Sigma, Depuy, Johnson and Johnson) Not described Gender solutions high-flex prosthesisD Cemented NexGen LPS-flexD Genesis II TKRC fixed-bearing inlay Genesis II TKRC mobile-bearing inlay Genesis II TKRC fixed-bearing inlay Genesis II TKRC mobile-bearing inlay Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Patient-specific instrumentation\ Conventional instrumentation Cemented tricompartmental posterior-stabilised prosthesis with mobile bearingH mini-subvastus approach Cemented tricompartmental posterior-stabilised prosthesis with mobile bearingH medial parapatellar approach Posterior stabilized total knee prosthesis

KAM mid stance phase [Nm] Mid stance KAM [N m/BW Ht] Max KAM [Nm/kg] braking phase Max KAM [Nm/kg] propulsion phase Max KAM [Nm/kg]

0.43 (0.35) 2.41 (0.83) 5.36 (2.13) 4.82 (2.23) 0.44 (0.13)

0.23 (0.23) 1.74 (0.64) 5.09 (1.90) 3.754 (2.01) 0.30 (0.08)

0.022 NA NR 0.034 NA

0.68 (0.04, 1.31) 0.88 (0.11, 1.66) 0.13 (−0.59, 0.85) 0.57 (−0.16, 1.30) 1.30 (0.54, 2.06)

NI 0.9 NI NI 0.46 (0.13)

NA NA NA NA p b 0.05

Max KAM [Nm/kg]

0.40 (0.17)

0.26 (0.11)

NA

0.97 (0.24, 1.71)

0.46 (0.13)

p b 0.05

Peak KAM [Nm/BWxHt%]

2.9 (1.4)

2.1 (1.0)

0.040

0.66 (0.17, 1.15)

1.8 (0.5)

0.27

Peak KAM [N m/BW Ht] KAM# [Nm/kg] KAM# [Nm/kg] KAM impulse [Nm*s/BWxht%]

3.08 (0.80) 0.5 0.48 1.1 (0.6)

2.41 (0.65) 0.4 0.38 1.2 (0.4)

NA 0.0 0.1 0.02

0.90 (0.12, 1.67) no standard deviation no standard deviation −0.20 (−0.67, 0.28)

3.13 NI NI 1.4 (0.4)

NA NA NA 0.33

KAM impulse [N m s/BW Ht] Max external KAM [N mm/kg] Max external KAM [N mm/kg] 1st max KAM[%BW] 1st max KAM [%BW] 2nd max KAM [%BW] 2nd max KAM [%BW] Max knee abduction moment [Nm/kg]

1.35 (0.20) 585 (201.5) 550.6 (223.9) 34.0 (17.0) 38.0 (16.0) 31.0 (14.0) 36.0 (16.0) −0.13 (0.19)

0.84 (0.21) 556.6 (139.4) 528.4 (119.5) 34.0 (14.0) 38.0 (18.0) 34.0 (15.0) 34.0 (24.0) −0.10 (0.04)

p b 0.01 NA NA NR NR NA NA NA

2.42 (1.44, 3.39) 0.16 (−0.49, 0.82) 0.13 (−0.53, 0.78) 0.00 (−0.48, 0.48) 0.00 (−0.48, 0.48) −0.20 (−0.69, 0.28) 0.10 (−0.38, 0.58) −0.25 (−0.95, 0.44)

0.84 (0.12) NI NI NI NI NI NI −0.11 (0.04)

NR NA NA NA NA NA NA NR

Max knee abduction moment [Nm/kg]

−0.06 (0.05)

−0.13 (0.07)

NA

1.14 (0.39, 1.88)

−0.11 (0.04)

NR

Knee abduction moment# [Nm/kg] Knee abduction moment# [Nm/kg] External knee abduction moment [Nm/kg]

−0.12 −0.12 0.41 (0.18)

−0.05 −0.1 0.32 (0.08)

0.34 0.5 0.005

no standard deviation no standard deviation −1.37 (−1.88, −0.86)

NI NI NI

NA NA NA

External knee abduction moment [Nm/kg]

0.35 (0.18)

0.26 (0.08)

0.044

0.68 (0.21, 1.16)

NI

NA

External abduction moment [%BWxBH] at 1st peak vertical GRF

4.07 (0.38)

3.01 (0.30)

p b 0.0125

3.06 (2.17, 3.95)

−3.07 (0.30)

NR

Urwin, 2013

Worsley, 2013

Metcalfe, 2013 Abdel, 2014 Worsley, 2013

Metcalfe, 2013 Thomsen, 2012 Tibesku, 2011 Tibesku, 2011 Urwin, 2013

Abdel, 2014 Wegzryn, 2012

Wegzryn, 2012

Mandeville, 2008

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Author

Table 4 Changes in sagittal plane kinematics following knee arthroplasty. Author, year

Surgical Detail

Levinger, 2013

Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC

Thomsen, 2012 Levinger, 2012

D

Gender Solutions high-flex prosthesis Cemented NexGen LPS-flexD Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC

Pre-op KA

Post-op KA

p-value: within KA group comparison

Effect sizes (95% confidence interval)

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

Knee IC

14.13 (5.29) 11 (5.2) 11 (8.3) 16.3 (6.3) 13.5 (4.8) 15 (3.42) 16.26 (4.14) 13.75 (1.23) 10 (6)

12.79 (3.78) 6 (6.5) 7 (4.3) 15.5 (3.6) 13.1 (4.0) 7 (5.11)

0.494

0.29 (-0.23, 0.82)

9.82 (3.27)

0.11

NA NA NA

0.84 (0.25, 1.43) 0.62 (0.05, 1.20) 0.16 (-0.33, 0.65)

NI NI NI

NA NA NA

NA

0.09 (-0.40, 0.58)

NI

NA

p b 0.05

1.86 (1.40, 2.32)

7 (2.5)

NA

7 (5.65)

p b 0.05

1.88(1.42, 2.32)

7 (2.5)

NA

10.63 (1.16) 8 (4)

NR

2.56 (1.75, 3.38)

16.09 (1.15)

p b 0.0125

0.055

0.40 (-0.08, 0.88)

7 (3)

0.418

16.55 (8.75) 16.32 (8.27) 16 (8)

13.56 (8.02) 13.82 (7.51) 15 (5)

0.113

0.35 (-0.28, 0.97)

NI

NA

0.194

0.31 (-0.31, 0.93)

NI

NA

0.712

-1.37 (-1.90, -0.84)

18 (4)

0.025

17.46 (10.11) 8 (8)

19.19 (9.97) 5 (6)

0.518

-0.17 (-0.79, 0.45)

NI

NA

0.002

0.42 (-0.06, 0.90)

4 (4)

0.492

30.26 (11.27) 22.43 (8.64) 54.75 (10.67) 54.77 (9.85) 21 (5.6) 22 (8.8) 11.50 (5.01) 12.00 (4.98) 22.5 (5.2) 22.6 (9.9) 12.7

33.41 (9.81) 20.97 (4.15) 64.01 (4.02) 63.79 (7.75) 16 (7.8) 17 (7.4) 20.50 (6.06) 21.67 (4.59) 24.1 (3.3) 20.1 (4.8) 8.4

0.228

-1.87 (-2.62, -1.13)

NI

NA

0.961

0.23 (-0.26, 0.73)

20.96 (5.40)

1.000

NA

-1.23 (-1.98, -0.47)

64.16 (2.74)

NR

NA

-1.00 (-1.73, -0.26)

64.16 (2.74)

NR

NA NA p b 0.05

0.73 (0.15, 1.32) 0.61 (0.03, 1.19) -1.61 (-2.06, -1.17)

NI NI 22.05 (3.11)

NA NA NR

p b 0.05

-2.01 (-2.48, -1.53)

22.05 (3.11)

NR

NA

-0.37 (-0.87, 0.12)

NI

NA

NA

0.34 (-0.16, 0.83)

NI

NA

0.37

no standard deviation

NI

NA

13.9 (9.3) 13.2 (10.0) 11.11 (6.54) 9 (5.8) 9 (9.5) 13.1 (5.5) 10.1 (7.0)

22.6 (8.6) 20.8 (7.5) 8.89 (5.55) 2 (6.3) 2 (6.4) 14.3 (3.3) 8.6 (4.8)

0.0075

-0.96 (-1.47, -0.45)

NI

NA

0.0052

-0.86 (-1.36, -0.35)

NI

NA

0.651

0.36 (-0.17, 0.89)

1.83 (4.63)

0.002

NA NA NA

1.14 (0.53, 1.75) 0.87 (0.27, 1.46) -0.27 (-0.76, 0.22)

NI NI NI

NA NA NA

NA

0.25 (-0.24, 0.74)

NI

NA

Knee flexion IC Knee flexion IC Knee angle at IC* Knee angle at IC**

Xu, 2010

Patella resurfacing Patella nonresurfacing

Mandeville, 2007 Smith, 2003 Apostolopoulos, 2011 Apostolopoulos, 2011 Smith, 2003 Apostolopoulos, 2011 Smith, 2003

3 compartment posterior stabilised or a cruciate retaining prosthesis Profix total knee systemE PCL retaining total knee prosthesis PCL retaining total knee prosthesis Profix total knee system

E

PCL retaining total knee prosthesis Profix total knee system

E

Apostolopoulos, 2011 Levinger, 2013

PCL retaining total knee prosthesis

Urwin, 2013

Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Gender Solutions high-flex prosthesisD Cemented NexGen LPS-flexD Patella resurfacing

Thomsen, 2012 Xu, 2010

A

B

A

Scorpio NRG , Active TKR , Triathlon , Genesis II

C

Levinger, 2012

Max knee flexion Max knee flexion Max knee flexion Max knee flexion Max knee flexion Max knee flexion

Patella nonresurfacing A

Knee flexion at heel strike Knee flexion at heel strike Knee angle at weight acceptance Min knee flexion angle at heel strike Sagittal plane knee angle first touch Sagittal plane knee angle early stance Max knee flexion angle mid stance Sagittal plane knee angle mid stance Min knee flexion angle late stance Sagittal plane knee angle late stance Max knee flexion

B

Scorpio NRG , Active TKR , TriathlonA, Genesis II

C

Max knee flexion* Max knee flexion**

Liebensteiner, 2008 Tibesku, 2011

Cemented total knee prosthesis

F

Max knee flexion

C

Genesis II TKR fixed-bearing inlay

1st max knee flexion

C

1st max knee flexion

Genesis II TKR mobile-bearing inlay Levinger, 2013 Thomsen, 2012 Levinger, 2012

A

B

#

A

Scorpio NRG , Active TKR , Triathlon , Genesis II D

C

Gender Solutions high-flex prosthesis Cemented NexGen LPS-flexD Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC

Knee extension Max knee extension Max knee extension Max knee extension* Max knee extension**

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Variable Measured

1001

(continued on next page)

1002

Table 4 (continued) Surgical Detail

Variable Measured

Pre-op KA

Post-op KA

p-value: within KA group comparison

Effect sizes (95% confidence interval)

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

Urwin, 2013

Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Genesis II TKRC fixed-bearing inlay

Min knee flexion

12.90 (10.24) 13.18 (10.50) 4.6 (7.9)

NA

-0.21 (-0.90, 0.49)

6.18 (3.16)

p b 0.05

NA

-0.50 (-1.20, 0.21)

6.18 (3.16)

p b 0.05

0.0016

-1.22 (-1.75, -0.70)

NI

NA

0.0023

-1.05 (-1.57, -0.54)

NI

NA

0.302

-0.45 (-0.94, 0.05)

59.24 (4.24)

0.078

0.094

-0.46 (-1.18, 0.27)

NI

NA

0.013

-0.69 (-1.26, -0.12)

NI

NA

Knee flexion ROM Knee flexion ROM

2.4 (10.4) 46.74 (12.41) 41.7 (9.7) 37.51 (14.35) 29 (5) 25 (6)

14.53 (5.26) 16.99 (4.45) 14.8 (8.6) 12.4 (8.4) 51.07 (6.72) 45.5 (6.4) 46.29 (10.73) 46 (7) 47 (6)

NA NA

-2.81 (-3.39, -2.23) -3.63 (-4.31, -2.96)

51 (6) 51 (6)

NA NA

Knee flexion ROM

28 (6)

48 (7)

NA

-3.05 (-3.66, -2.44)

51 (6)

NA

Total knee flexion during loading Knee ROM

6 (5)

7 (4)

0.029

-0.22 (-0.64, 0.20)

11 (3)

p b 0.001

45.8 (7.0) 50.8 (8.0) 49.48 (6.62) 46.79 (9.41) 53 (7) 53 (7)

NA

-0.01 (-0.50, 0.48)

NI

NA

NA

-0.33 (-0.83, 0.16)

NI

NA

NA

-0.95 (-1.68, -0.22)

57.97 (3.73)

0.08

NA

-0.57 (-1.28, 0.14)

57.97 (3.73)

p b 0.05

Max knee flexion Max knee flexion

45.7 (10.5) 47.2 (13.4) 41.85 (9.086) 41.59 (8.38) 43 (4) 42 (7)

NA NA

-1.80 (-2.29, -1.31) -1.56 (-2.03, -1.09)

58 (6) 58 (6)

NA NA

Max knee flexion

42 (6)

55 (7)

NA

-1.98 (-2.49, -1.48)

58 (6)

NA

Min knee flexion Min knee flexion

13 (3) 16 (4)

7 (3) 6 (2)

NA NA

1.98 (1.48, 2.49) 3.30 (2.67, 3.94)

6 (4) 6 (4)

NA NA

Min knee flexion

13 (4)

6 (3)

NA

1.98 (1.48, 2.49)

6 (4)

NA

1st ROM knee flexion 1st ROM knee flexion

9.3 (3.4) 10.8 (4.4) 13.96 (10.28) 14.80 (10.92) 26.73 (11.59) 24.38 (8.79)

7.8 (4.1) 8.5 (4.0)

NR NR

0.40 (-0.09, 0.88) 0.54 (0.05, 1.03)

NI NI

NA NA

17.65 (6.41) 17.22 (3.60) 27.92 (9.50) 22.20 (4.95)

NA

-0.43 (-1.13, 0.27)

11.00 (3.89)

p b 0.05

NA

-0.32 (-1.02, 0.37)

11.00 (3.89)

0.08

NA

-0.11 (-0.80, 0.58)

25.52 (5.57)

NR

NA

0.31 (-0.39, 1.01)

25.52 (5.57)

NR

Tibesku, 2011

C

B

Min knee flexion Min knee flexion

Genesis II TKR mobile-bearing inlay A

Min knee flexion

A

C

Levinger 2013

Scorpio NRG , Active TKR , Triathlon , Genesis II

Max knee ROM

Orishimo, 2012

Posterior-stabilized TKA

Knee flexion ROM

Chang, 2011

Knee flexion ROM

Smith, 2003

Cruciate-retaining, cemented without patella resurfacing Conventional TKR method Conventional TKR method with computer-assisted navigation Minimal invasive technique with computer-assisted navigation Profix total knee systemE

Levinger, 2012

Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC

Bejek, 2011

Knee ROM Urwin, 2013

Bejek, 2011

Bejek, 2011

Tibesku, 2011

Urwin, 2013

Urwin, 2013

Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Conventional TKR method Conventional TKR method with computer-assisted navigation Minimal invasive technique with computer-assisted navigation Conventional TKR method Conventional TKR method with computer-assisted navigation Minimal invasive technique with computer-assisted navigation Genesis II TKRC fixed-bearing inlay Genesis II TKRC mobile-bearing inlay Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK

*flexor moment pattern **biphasic moment pattern post-op measurements taken from last time point reported # measure of variability other than standard deviation reported

Sagittal plane knee ROM Sagittal plane knee ROM

Knee flexion at max extension moment Knee flexion at max extension moment Knee flexion at max flexion moment Knee flexion at max flexion moment

A = Stryker, USA B = ASDM, Australia C = Smith & Nephew, Germany D = Zimmer E = Smith & Nephew Richards Inc, Memphis, TN F = Kinemax, Stryker, Kalamazoo, Michigan G = W. Link Gmbh and Co., Germany H = Sigma RP knee system; DePuy Orthopaedics, Inc, Warsaw, IN, USA

IC = initial contact ROM = range of motion TKR = total knee replacement GRF = ground reaction force KAM = knee adduction moment PCL = posterior cruciate ligament

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Author, year

NA= not statistically analysed NR= analysed, p-value not reported NI= not included

Table 5 Changes in sagittal plane moments following knee arthroplasty. Surgical Detail

Variable Measured

Mandeville, 2007 Smith, 2003

3 compartment posterior stabilised or a cruciate retaining prosthesis Profix total knee systemE

Smith, 2003

Profix total knee systemE

Smith, 2003

Profix total knee systemE

External knee flexor moment at weight acceptance [%BWxBH] Knee flexion moment initial extension [N m/kg] Knee flexion moment early midstance flexion [N m/kg] Knee flexion moment terminal stance extension [N m/kg] Peak knee flexion moment [%BWxH] Knee flexion moment [Nm/kg]

A

B

A

C

Levinger, 2013

Scorpio NRG , Active TKR , Triathlon , Genesis II

Vahtrik, 2013

Condylar endoprosthesis GEMINIG

Worsley, 2013

Unilateral (The Oxford, Biomet Orthopaedics), Total (P.F.C. Sigma, Depuy, Johnson and Johnson) Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Genesis II TKRC fixed-bearing inlay

Urwin, 2013

Tibesku, 2011

Genesis II TKRC mobile-bearing inlay Thomsen, 2012

Gender Solutions high-flex prosthesis Cemented NexGen LPS-flexD

Xu, 2010

Patella resurfacing

D

Pre-op KA

0.23 (0.53) -0.31 (0.09) 0.18 (0.20) -0.06 (0.24) 2.27 (1.33) 0.18 (0.06) Peak knee flexion moment [Nm/ 2.1 BWxHt%] (0.7) Max knee flexion moment [Nm/kg] 0.54 (0.35) Max knee flexion moment [Nm/kg] 0.49 (0.29) Max knee flexion moment [%BW] 21.0 (20.0) Max knee flexion moment [%BW] 14.0 (24.0) Max knee flexion moment [N mm/ 511.3 kg] (212.5) Max knee flexion moment [N mm/ 511.5 kg] (210.8) Max flexion moment [Nm] 0.43 (0.12)

Post-op KA

p-value: within KA group comparison

Effect sizes (95% confidence interval)

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

0.70 (0.38) -0.43 (0.10) 0.20 (0.16) -0.16 (0.18) 3.20 (1.22) 0.21 (0.06) 2.1 (0.7) 0.75 (0.40) 0.73 (0.25) 30.0 (22.0) 20.0 (21.0) 499.3 (208.4) 539.3 (246.6) 0.73 (0.39)

NR

-1.01 (-1.66, -0.37)

-1.22 (0.38)

p b 0.0125

p b 0.001

1.25 (0.79, 1.71)

-0.38 (0.10)

0.066

0.574

-0.11 (-0.53, 0.31)

0.30 (0.09)

0.004

0.002

0.47 (0.04, 0.90)

-0.21 (0.12)

0.231

0.029

-0.72 (-1.26, -0.18)

3.32 (1.25)

1.000

NA

-0.48 (-1.26, 0.30)

0.51 (0.06)

p b 0.001

0.34

0.00 (-0.48, 0.48)

2.6 (0.5)

0.570

NA

-0.55 (-1.25, 0.16)

0.96 (0.30)

0.670

NA

-0.87 (-1.59, -0.14)

0.96 (0.30)

0.590

NR

-0.42 (-0.91, 0.06)

NI

NA

NR

-0.26 (-0.75, 0.22)

NI

NA

NA

0.06 (-0.60, 0.71)

NI

NA

NA

-0.12 (-0.77, 0.54)

NI

NA

NR

-1.17 (-1.58, -0.75)

0.73 (0.42)

NA

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Author

(continued on next page)

1003

1004

Table 5 (continued) Author

Levinger, 2012

Tibesku, 2011

Surgical Detail

Variable Measured

Patella nonresurfacing

Max flexion moment [Nm]

Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC

C

Genesis II TKR fixed-bearing inlay C

Genesis II TKR mobile-bearing inlay Gender Solutions high-flex prosthesisD Cemented NexGen LPS-flexD Urwin, 2013

Xu, 2010

Fixed-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Mobile-bearing (Sigma® Fixed Bearing Knee System, DePuy International, Leeds, UK Patella resurfacing Patella nonresurfacing

Smith, 2003

Profix total knee system

E

Apostolopoulos, PCL retaining total knee prosthesis 2011 Levinger, 2013 Scorpio NRGA, Active TKRB, TriathlonA, Genesis IIC Levinger, 2012

A

B

Scorpio NRG , Active TKR , TriathlonA, Genesis II

*flexor moment pattern **biphasic moment pattern post-op measurements taken from last time point reported # measure of variability other than standard deviation reported

C

0.45 (0.10) External knee flexion moment* 2.59 [Nm] (1.13) External knee flexion moment** 2.10 [Nm] (1.40) Min knee flexion moment [%BW] -17.0 (17.0) Min knee flexion moment [%BW] -27.0 (23.0) Min knee flexion moment [N mm/ -11.5 kg] (138.8) Min knee flexion moment [N mm/ -4.0 kg] (223.8) Max knee extension moment [Nm/ -0.28 kg] (0.15) Max knee extension moment [Nm/ -0.25 kg] (0.043) Max extension moment [Nm] 0.23 (0.11) Max extension moment [Nm] 0.22 (0.07) Knee flexion moment pre-swing 0.26 flexion [N m/kg] (0.11) Average knee flexion extension 0.01 moment [Nm] (0.27) Knee extension [%BWxH] -0.39 (1.01) External knee extension moment* -0.01 [Nm] (1.15) External knee extension moment** -0.62 [Nm] (0.96)

Post-op KA

p-value: within KA group comparison

Effect sizes (95% confidence interval)

Healthy Reference Group

p-value: between group (post-op KA compared to controls) comparison

0.51 (0.07) 3.09 (1.03) 2.41 (1.16) -5.0 (26.0) -16.0 (19.0) -145.6 (170.9) -104.4 (184.1) -0.38 (0.12) -0.34 (0.097) 0.24 (0.08) 0.21 (0.05) 0.17 (0.05) 0.05 (0.28) -0.77 (1.03) 0.29 (0.55) -0.76 (0.70)

NR

-0.70 (-1.10, -0.30)

0.73 (0.42)

NA

NA

-0.46 (-0.95, 0.04)

NI

NA

NA

-0.24 (-0.73, 0.25)

NI

NA

NR

-0.55 (-1.04, -0.06)

NI

NA

NR

-0.52 (-1.01, -0.03)

NI

NA

NA

0.85 (0.16, 1.53)

NI

NA

NA

0.48 (-0.18, 1.14)

NI

NA

NA

0.72 (0.01, 1.44)

-0.39 (0.047)

1

NA

1.25 (0.50, 2.01)

-0.39 (0.047)

0.75

NR

-0.10 (-0.49, 0.28)

0.39 (0.10)

NA

NR

0.17 (-0.22, 0.55)

0.39 (0.10)

NA

p b 0.001

1.11 (0.66, 1.57)

0.19 (0.05)

0.399

0.621

-0.14 (-0.76, 0.48)

NI

NA

0.59

0.37 (-0.13, 0.86)

-1.97 (0.88)

0.002

NA

-0.35 (-0.84, 0.15)

NI

NA

NA

0.17 (-0.32, 0.66)

NI

NA

A = Stryker, USA B = ASDM, Australia C = Smith & Nephew, Germany D = Zimmer E = Smith & Nephew Richards Inc, Memphis, TN F = Kinemax, Stryker, Kalamazoo, Michigan G = W. Link Gmbh and Co., Germany H = Sigma RP knee system; DePuy Orthopaedics, Inc, Warsaw, IN, USA

IC = initial contact ROM = range of motion TKR = total knee replacement GRF = ground reaction force KAM = knee adduction moment PCL = posterior cruciate ligament

NA = not statistically analysed NR = analysed, p-value not reported NI = not included

L. Sosdian et al. / The Knee 21 (2014) 994–1008

Thomsen, 2012

Pre-op KA

L. Sosdian et al. / The Knee 21 (2014) 994–1008

1005

43–45] evaluating patients at a single post-operative time point. Ten of the 19 studies [3,4,12,35,37,38,40–42,45] included a healthy, asymptomatic control group.

characteristics were reported separately across sub-groups (e.g. according to prosthesis received), data were combined and averaged where appropriate. Means and standard deviations of relevant quantitative gait data were extracted during stance phase. Where multiple time points were reported, only data from the longest post-operative time point was recorded. When point estimates were not provided, data were extracted from graphs using an online point estimation tool (WebPlotDigitizer http://arohatgi.info/WebPlotDigitizer/). Gait variables were categorized by plane of motion, as either an angle or a moment, and by timing within stance phase. Results of statistical tests from within-KA group analyses and/or between-group (post-operative KA and healthy groups, where relevant) comparisons were also extracted. Variable descriptors for knee joint kinematics as reported in original studies were retained. Joint moments reported as internal were converted to external moments for consistency (e.g. internal extension moment = external flexion moment), unless this was unclear whereby authors were contacted for clarification.

Relatively few studies (n = 7, 37%) evaluated longitudinal changes in frontal plane knee kinematics (Table 2). Two studies demonstrated significant increases in the abduction (valgus) angle at initial contact, at first peak vertical ground reaction force (GRF), and at mid stance [36,38]. Another study also reported a significant decrease in the knee abduction angle, although the timing within stance was not specified [43]. To highlight the variability of results, the effect sizes for selected frontal plane variables have been plotted (Fig. 2a and b). Fig. 2a demonstrates that overall, the maximum knee adduction angle was reduced following surgery, although two of these studies reported non-significant changes [31,45]. Post-operative adduction angles approximated those of healthy people, although this was not confirmed statistically [37]. Of the six studies reporting a parameter of the KAM, four reported a significant decrease in this moment at six [41], nine [36], and 12 [3,31] months post-operatively (Table 3). For those studies in which effect sizes could be calculated [3,30,33,41,45], four reported a decrease in KAM, whilst one reported no change [33]. Two studies reported conflicting results regarding the KAM impulse, with one reporting a decrease at 12 months [3] and the other reporting an increase at six months after surgery [41] from pre-operative values.

2.3. Quality evaluation

3.3. Sagittal plane

3.2. Frontal plane

Compared to the frontal plane, more studies (n = 14, 74%) reported sagittal plane kinematic data (Table 4). One study reported that patients exhibited a more extended knee at initial contact [37]. Inconsistent changes pre- to post-operatively were reported for maximum knee flexion during stance with two studies reporting a significant increase at least 12 months post-surgery [33,37] and three reporting non-significant decreases between three and 12 months [4,30,39]. This inconsistency of findings is highlighted by the mix of positive and negative effect sizes displayed in Fig. 2c. Many of the sagittal plane kinematic variables were not statistically different after surgery. Generally, there was an increase in the peak knee flexion moment after surgery, as indicated by the mostly negative effect sizes shown in Fig. 2d; however, only two studies found this change to be significant [4,37]. A significantly increased external knee flexion moment in early and late stance between 12-18 months was observed in a single study [12] (Table 5).

Study quality was evaluated by two reviewers independently (LS and KA), with disagreements resolved by consensus. The Downs and Black checklist was used [27], which is recommended for randomized controlled trials and non-randomized study designs. Questions related to an intervention were excluded (14, 15, 19, 23, 24, 25, 27) as papers could not be scored on these items. Therefore, risk of bias was evaluated on the remaining 20 questions. 2.4. Data analysis Within-subject effect sizes and 95% confidence intervals for pre/postsurgery data for those studies that included a mean value and a standard deviation were calculated using Hedge’s g (average). This method is recommended for calculating effect sizes for correlated groups, such as within-subject changes in pre-post study designs. [28,29].

3.4. Comparison to control group, where available Ten studies (53%) included data from a healthy reference group for comparison with the KA samples. Some studies demonstrated that several, but not all, gait parameters were within normal limits at one year following surgery. Out of the eight studies reporting a KAM variable, two studies included a healthy comparison group. One of these reported that the peak KAM was within the range of the healthy cohort [41], whilst the other reported that the KA group remained significantly different after surgery [45]. Although the post-operative peak external knee flexion moment was found to be significantly increased from the pre-operative value, it was also found to be comparable to that of the control group [4]. Of the six studies that reported sagittal plane moments, four included statistical comparisons with healthy reference groups and found KA values that were both higher [4,40] and lower [12,42,45] than the control group.

3. Results 3.1. Study characteristics Fig. 1 outlines the selection of papers. Nineteen studies [3,4,12,30–45] satisfied the eligibility criteria (Fig. 1 and Table 1). Duration of post-operative follow-up varied between 2 and 24 months with most (12/19, 63%) studies [3,4,12,30,33,34,36,38–41,

Table 6 Quality appraisal of included studies using the Downs and Black tool. Author, Year

Abdel, M. 2014 Urwin, S. G. 2013 Worsley, P. 2013 Vahtrik, D. 2013 Levinger, P. 2013 Wegrzyn, J. 2012 Thomsen, M. G. 2012 Orishimo, K. F. 2012 Levinger, P. 2012 Tibesku, C. O. 2011 Metcalfe, Andrew 2011 Chang, Q. Z. 2011 Bejek, Z. 2011 Apostolopoulos, A. 2011 Xu, Y-M 2010 Mandeville, D. 2008 Liebensteiner, M. C. 2008 Mandeville, D. 2007 Smith, A. J. 2003

Item 1

2

3

4

5

6

7

8

9

10

11

12

13

16

17

18

20

21

22

26

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

0 0 1 1 1 0 0 1 1 0 1 1 0 1 0 1 1 1 1

1 1 1 1 1 1 1 1 1 1 1 0 1 1 0 0 0 0 1

1 1 1 1 1 1 1 1 1 1 0 1 0 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1 0 1 0 1 1 1 0 0 1 1

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

1 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 0

1 0 0 0 1 1 1 1 1 1 0 1 0 1 0 0 1 0 1

1 0 0 0 0 1 1 0 0 0 1 0 0 0 0 0 1 0 1

1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

1 0 1 1 1 0 1 1 1 1 0 1 1 0 0 1 1 1 1

0 1 1 1 1 1 1 1 1 0 0 1 0 1 1 1 1 1 0

0 1 0 0 1 0 1 0 0 0 1 0 1 0 0 0 1 0 1

0 0 1 0 1 1 0 0 1 1 1 1 1 0 1 1 1 1 1

1 0 0 0 1 1 1 0 1 0 1 0 0 0 0 0 1 0 1

1 0 0 0 0 1 1 0 0 1 0 1 0 0 1 0 0 0 1

1 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 0

1006

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3.5. Quality evaluation Quality evaluation ratings ranged from 9 to 16 points out of a possible 20 points (Table 6). While most studies performed well regarding reporting (questions 1-10), all studies were at risk of selection bias and most (n = 15/19, 79%) were at risk of attrition bias as there was insufficient information about participant recruitment, representativeness, and loss to follow-up.

4. Discussion Both pre- and post-operative gait biomechanics are relevant to KA outcomes with regards to the presence of knee pain, patient satisfaction, and implant longevity. This systematic review aimed to synthesize the effects of KA on changes in frontal and sagittal plane gait kinetics and kinematics and compare post-operative gait parameters to those of a healthy reference group where possible. The main findings of this systematic review were that KA results in a decreased peak KAM and maximum knee adduction angle, an increased peak knee flexion moment, and inconsistent changes in the maximum knee flexion angle. Numerous methodological and reporting weaknesses in the current body of knowledge were identified as well as gaps in the literature, providing clear directions for future research. Although few studies evaluated frontal plane kinematics, there is evidence to suggest that KA does change these variables, likely due to the correction of frontal plane alignment with surgery. KA reduces the peak KAM, and affects the KAM impulse, although there is conflicting evidence as to whether the KAM impulse increases or decreases with surgery. An elevated external peak KAM leads to increased force on the medial knee compartment relative to the lateral, and could be a contributor to increased force on the knee implant if the KAM is not reduced with surgery. However, only six out of 19 included studies evaluated the effect of arthroplasty on the peak KAM. Since this moment results primarily from the GRF vector and its distance (lever arm) from the knee center in the frontal plane, correcting knee alignment towards neutral with KA should reduce the KAM post-operatively. Although five of the six studies evaluating the KAM demonstrated a reduction from preoperative values, it is unclear whether the KAM is restored within normal limits. Only two studies included a healthy reference group. One showed a return to normal values [41], while the other did not undertake statistical comparisons with the arthroplasty group [3]. If the KAM remains higher than normal after KA, it is possible that this could contribute to ongoing knee symptoms following surgery. Furthermore, it could contribute to failure to maintain post-surgical neutral knee alignment, as evident from a study investigating high tibial osteotomy [46], which could subsequently lead to reduced implant survival rates [22]. Despite the fact that long-term pain and satisfaction scores in KA patients are acceptable [47], it is not clear whether gait biomechanics are returned to normal [17,18]. There is limited evidence suggesting that in the sagittal plane, individuals walk with an increased range of motion after KA and have a higher maximum knee flexion angle. It appears that the peak knee flexion moment is increased following surgery, but many studies did not report statistical analyses, and it is unclear whether an increased peak knee flexion moment might return to normal values. In the studies that did report statistical analyses, four found that sagittal plane moments remained significantly different from healthy individuals after KA. Differences within the KA populations in each study could contribute to inconsistent outcomes. Conflicting information makes it difficult to discern how sagittal plane biomechanics change longitudinally following KA. Noticeable heterogeneity between the studies in this review was evident with respect to the type of implant used. Some studies evaluated KA cohorts with mixed implant designs [4,32,41], which could have introduced confounding results with respect to changes in gait pattern following surgery. One study did not describe the type of implant used [3]. Whilst a number of studies ensured their cohorts all received the same type of implant, the actual implants received varied across studies

and included cemented [34,39], posterior-stabilized [31,38,40], and posterior cruciate ligament retaining [36] implants, among others. Few studies specifically evaluated the effects of different implants on knee kinematics and moments, including a gender-specific implant design [30], a patella-resurfaced versus a non-resurfaced design [37], and a mobile versus a fixed-bearing prosthesis [45]. These studies found no differences in gait variables between designs. Similarly, few studies have considered whether surgical technique influences changes in gait post-operatively. One study reported no differences in gait variables when using a minimally invasive technique, conventional technique, or computer-assisted surgery [35]. Two other two studies did not report any benefits of minimally invasive versus conventional methods [43] or advantages due to patient-specific instrumentation [44]. The methodological quality of the studies included in this systematic review was generally good, although the studies were quite heterogeneous with respect to methodological approaches, reporting, and implant design, eliminating the possibility of meta-analyses. Moreover, statistical analyses were sometimes not performed or the results were not reported, making it difficult to conclusively determine how KA changes gait biomechanics. More consistent reporting with the use of STROBE guidelines for observational studies should be employed by researchers in the future [48]. The differences between gait analysis systems and modeling techniques used made it difficult to know if the quality was consistent across all studies included in this systematic review. The majority of studies provided basic detail with regards to the type of 3D gait analysis, but the number of cameras used varied, and only seven studies [3,4,32,33,39,41,45] reported the type of marker model used. Discrepancies in the KAM and knee flexion moments have previously been reported in studies that allowed participants to walk at selfselected or constrained walking speeds [49]. While most studies in this systematic review used self-selected walking speeds, one treadmill study used a speed of 0.56 m/s [35], three studies were not specific [30, 37,41], and a single study mentioned that their participants wore shoes during the gait trials [12]. Consistency in these areas of reporting would assist with interpretation of results. Strengths of this systematic review include a comprehensive and reproducible search strategy, the inclusion of frontal plane parameters in addition to sagittal, and the use of a quality assessment tool. This systematic review includes several new studies that were not included in previous systematic reviews [17,18], and did not require the presence of a control group. This is the first systematic review to investigate longitudinal changes in knee kinematics and moments, as the aim of previous reviews was to compare post-operative kinematics, moments, and spatiotemporal parameters to those of a healthy control group. Limitations of this study include an exclusion of studies not written in English (n = 4) and a lack of meta-analysis, which might have provided further insight as to the overall direction of inconsistent findings such as the significant increase in KAM impulse found in one study [41] and the decrease found in another [3]. Whilst within-group effect sizes were calculated for each variable, these were difficult to interpret for some variables due to the unknown clinical relevance of the directional change. Studies that used alternative analysis techniques that did not yield a point estimate (e.g. PCA) could not be included. Current literature analyzing changes in gait kinetics and kinematics following KA largely evaluates patients as a single homogeneous group. It is quite likely that such patients are heterogeneous and thus possible that gait patterns and effects of arthroplasty differ between sub-groups of patients with different characteristics. The only characteristics identified in this review, and in relatively few studies, were prosthesis type and surgical procedure [30,33,35,37]. Given the prevalence of obesity amongst those undergoing arthroplasty, and concerns regarding its effect on outcomes including worse Western Ontario and McMaster Universities and Arthritis Index (WOMAC) pain and function scores, knee stiffness [50], poor range of motion [51], and increased KA revision rates [52], future research should investigate whether obesity

L. Sosdian et al. / The Knee 21 (2014) 994–1008

influences the impact of KA on gait biomechanics. Obese individuals demonstrate different gait patterns to those of normal weight, including a slower walking speed, wider step width, and increased stance and double support time [53], and it is likely that the gait patterns of obese patients following KA are also different to those who are not obese. Other subgroups worthy of future research are those with patella resurfacing compared to those without. In summary, this systematic review identified a number of studies that have evaluated longitudinal changes in gait kinematics and kinetics following KA. The main findings of this systematic review were that KA results in a decreased peak KAM and maximum knee adduction angle, an increased peak knee flexion moment, and inconsistent changes in the peak knee flexion angle. Variation in outcomes may reflect different responses of patient subgroups. The relationship between changes in gait biomechanical variables and changes in important patient factors such as pain, function, and quality of life should be investigated in order to determine the clinical relevance of changes in specific gait parameters, and whether specific gait retraining is needed following KA. Financial support This study was supported by funding from the Australian Research Council (#LP120100019) and the National Health and Medical Research Council (#61837). Kim Bennell (FT0991413) and Rana Hinman (FT130100175) are each partly funded by an Australian Research Council Future Fellowship. Michelle Dowsey holds an NHMRC Early Career Australian Clinical Fellowship (APP1035810). Conflict of Interest The authors declare that this manuscript is not under consideration by any other journal and has not been published in any journal or other citable form. The authors declare that they have no competing interests. All authors have read the manuscript and agreed to its content. References [1] Liddle AD, Pegg EC, Pandit H. Knee replacement for osteoarthritis. Maturitas 2013; 75:131–6. [2] Hurwitz DE, Ryals AR, Block JA, Sharma L, Schnitzer TJ, Andriacchi TP. Knee pain and joint loading in subjects with osteoarthritis of the knee. J Orthop Res 2000;18:572–9. [3] Metcalfe A, Stewart C, Postans N, Barlow D, Dodds A, Holt C, et al. Abnormal loading of the major joints in knee osteoarthritis and the response to knee replacement. Gait Posture 2013;37:32–6. [4] Levinger P, Menz HB, Morrow AD, Feller JA, Bartlett JR, Bergman NR. Lower limb biomechanics in individuals with knee osteoarthritis before and after total knee arthroplasty surgery. J Arthroplasty 2013;28:994–9. [5] Chang A, Hochberg M, Song J, Dunlop D, Chmiel JS, Nevitt M, et al. Frequency of varus and valgus thrust and factors associated with thrust presence in persons with or at higher risk of developing knee osteoarthritis. Arthritis Rheum 2010;62:1403–11. [6] Chang A, Hayes K, Dunlop D, Hurwitz D, Song J, Cahue S, et al. Thrust during ambulation and the progression of knee osteoarthritis. Arthritis Rheum 2004;50: 3897–903. [7] Miyazaki T, Wada M, Kawahara H, Sato M, Baba H, Shimada S. Dynamic load at baseline can predict radiographic disease progression in medial compartment knee osteoarthritis. Ann Rheum Dis 2002;61:617–22. [8] Astephen JL, Deluzio KJ, Caldwell GE, Dunbar MJ. Biomechanical changes at the hip, knee, and ankle joints during gait are associated with knee osteoarthritis severity. J Orthop Res 2008;26:332–41. [9] Baliunas AJ, Hurwitz DE, Ryals AB, Karrar A, Case JP, Block JA, et al. Increased knee joint loads during walking are present in subjects with knee osteoarthritis. Osteoarthritis Cartilage 2002;10:573–9. [10] Hunt MA, Birmingham TB, Giffin JR, Jenkyn TR. Associations among knee adduction moment, frontal plane ground reaction force, and lever arm during walking in patients with knee osteoarthritis. J Biomech 2006;39:2213–20. [11] Mills K, Hunt MA, Ferber R. Biomechanical deviations during level walking associated with knee osteoarthritis: a systematic review and meta-analysis. Arthritis Care Res (Hoboken) 2013;65:1643–65. [12] Smith AJ, Lloyd DG, Wood DJ. Pre-surgery knee joint loading patterns during walking predict the presence and severity of anterior knee pain after total knee arthroplasty. J Orthop Res Mar 2004;22(2):260–6. [13] van Jonbergen HP, Reuver JM, Mutsaerts EL, Poolman RW. Determinants of anterior knee pain following total knee replacement: a systematic review. Knee Surg Sports Traumatol Arthrosc 2014;22(3):478–99.

1007

[14] Turcot K, Sagawa Jr Y, Fritschy D, Hoffmeyer P, Suva D, Armand S. How gait and clinical outcomes contribute to patients' satisfaction three months following a total knee arthroplasty. J Arthroplasty 2013;28:1297–300. [15] Kaufman KR, Hughes C, Morrey BF, Morrey M, An KN. Gait characteristics of patients with knee osteoarthritis. J Biomech 2001;34:907–15. [16] Hilding MB, Lanshammar H, Ryd L. Knee joint loading and tibial component loosening. RSA and gait analysis in 45 osteoarthritic patients before and after TKA. J Bone Joint Surg Br 1996;78:66–73. [17] Milner CE. Is gait normal after total knee arthroplasty? Systematic review of the literature. J Orthop Sci 2009;14:114–20. [18] McClelland JA, Webster KE, Feller JA. Gait analysis of patients following total knee replacement: a systematic review. Knee 2007;14:253–63. [19] Halder A, Kutzner I, Graichen F, Heinlein B, Beier A, Bergmann G. Influence of limb alignment on mediolateral loading in total knee replacement: in vivo measurements in five patients. J Bone Joint Surg Am 2012;94:1023–9. [20] Zhao D, Banks SA, Mitchell KH, D'Lima DD, Colwell Jr CW, Fregly BJ. Correlation between the knee adduction torque and medial contact force for a variety of gait patterns. J Orthop Res 2007;25:789–97. [21] Werner FW, Ayers DC, Maletsky LP, Rullkoetter PJ. The effect of valgus/varus malalignment on load distribution in total knee replacements. J Biomech 2005;38: 349–55. [22] Ritter MA, Davis KE, Davis P, Farris A, Malinzak RA, Berend ME, et al. Preoperative malalignment increases risk of failure after total knee arthroplasty. J Bone Joint Surg Am 2013;95:126–31. [23] Cameron HU. Tibial component wear in total knee replacement. Clin Orthop Relat Res 1994;29–32. [24] Collier MB, Engh Jr CA, McAuley JP, Engh GA. Factors associated with the loss of thickness of polyethylene tibial bearings after knee arthroplasty. J Bone Joint Surg Am 2007;89:1306–14. [25] Wasielewski RC, Galante JO, Leighty RM, Natarajan RN, Rosenberg AG. Wear patterns on retrieved polyethylene tibial inserts and their relationship to technical considerations during total knee arthroplasty. Clin Orthop Relat Res 1994;31–43. [26] Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. J Clin Epidemiol 2009;62:1006–12. [27] Downs SH, Black N. The feasibility of creating a checklist for the assessment of the methodological quality both of randomised and non-randomised studies of health care interventions. J Epidemiol Community Health 1998;52:377–84. [28] Lakens D. Calculating and reporting effect sizes to facilitate cumulative science: a practical primer for -tests and ANOVAs. Front Psychol 2013;4:863. [29] Cumming G, Finch S. Inference by eye: confidence intervals and how to read pictures of data. Am Psychol 2005;60:170–80. [30] Thomsen MG, Husted H, Bencke J, Curtis D, Holm G, Troelsen A. Do we need a genderspecific total knee replacement? A randomised controlled trial comparing a high-flex and a gender-specific posterior design. J Bone Joint Surg Br 2012;94:787–92. [31] Orishimo KF, Kremenic IJ, Deshmukh AJ, Nicholas SJ, Rodriguez JA. Does total knee arthroplasty change frontal plane knee biomechanics during gait? Clin Orthop Relat Res 2012;470:1171–6. [32] Levinger P, Menz HB, Morrow AD, Perrott MA, Bartlett JR, Feller JA, et al. Knee biomechanics early after knee replacement surgery predict abnormal gait patterns 12 months postoperatively. J Orthop Res 2012;30:371–6. [33] Tibesku CO, Daniilidis K, Skwara A, Dierkes T, Rosenbaum D, Fuchs-Winkelmann S. Gait analysis and electromyography in fixed- and mobile-bearing total knee replacement: a prospective, comparative study. Knee Surg Sports Traumatol Arthrosc 2011; 19:2052–9. [34] Chang QZ, Sohmiya M, Wada N, Tazawa M, Sato N, Yanagisawa S, et al. Alternation of trunk movement after arthroplasty in patients with osteoarthritis of the knee. J Orthop Sci 2011;16:382–8. [35] Bejek Z, Paroczai R, Szendroi M, Kiss RM. Gait analysis following TKA: comparison of conventional technique, computer-assisted navigation and minimally invasive technique combined with computer-assisted navigation. Knee Surg Sports Traumatol Arthrosc 2011;19:285–91. [36] Apostolopoulos A, Lallos S, Mastrokalos D, Michos I, Darras N, Tzomaki M, et al. Kinematic and kinetic analysis of the knee joint before and after a PCL retaining total knee replacement during gait and single step ascent. J Long Term Eff Med Implants 2011;21:339–48. [37] Xu YM, Bai YH, Zhou J, Li QT, Liang J. Gait analysis in primary total knee arthroplasty with and without patellar resurfacing: A randomized control study. J Shanghai Jiaotong Univ (Sci) 2010;15:632–6. [38] Mandeville D, Osternig LR, Lantz BA, Mohler CG, Chou LS. The effect of total knee replacement on the knee varus angle and moment during walking and stair ascent. Clin Biomech (Bristol, Avon) 2008;23:1053–8. [39] Liebensteiner MC, Herten A, Gstoettner M, Thaler M, Krismer M, Bach CM. Correlation between objective gait parameters and subjective score measurements before and after total knee arthroplasty. Knee 2008;15:461–6. [40] Mandeville D, Osternig LR, Chou LS. The effect of total knee replacement on dynamic support of the body during walking and stair ascent. Clin Biomech (Bristol, Avon) 2007;22:787–94. [41] Worsley P, Stokes M, Barrett D, Taylor M. Joint loading asymmetries in knee replacement patients observed both pre- and six months post-operation. Clin Biomech. Avon: Bristol; 2013. [42] Vahtrik D, Gapeyeva H, Ereline J, Paasuke M. Relationship between leg extensor muscle strength and knee joint loading during gait before and after total knee arthroplasty. Knee 2014;21(1):216–20. [43] Wegrzyn J, Parratte S, Coleman-Wood K, Kaufman KR, Pagnano MW. The John Insall award: no benefit of minimally invasive TKA on gait and strength outcomes: a randomized controlled trial. Clin Orthop Relat Res 2013;471:46–55.

1008

L. Sosdian et al. / The Knee 21 (2014) 994–1008

[44] Abdel MP, Parratte S, Blanc G, Ollivier M, Pomero V, Viehweger E, et al. No Benefit of Patient-specific Instrumentation in TKA on Functional and Gait Outcomes: A Randomized Clinical Trial. Clin Orthop Relat Res 2014;472(8):2468–76. [45] Urwin SG, Kader DF, Caplan N, St Clair Gibson A, Stewart S. Gait analysis of fixed bearing and mobile bearing total knee prostheses during walking: do mobile bearings offer functional advantages? Knee 2014;21:391–5. [46] Prodromos CC, Andriacchi TP, Galante JO. A relationship between gait and clinical changes following high tibial osteotomy. J Bone Joint Surg Am 1985;67:1188–94. [47] Loughead JM, Malhan K, Mitchell SY, Pinder IM, McCaskie AW, Deehan DJ, et al. Outcome following knee arthroplasty beyond 15 years. Knee 2008;15:85–90. [48] Bolignano D, Mattace-Raso F, Torino C, D'Arrigo G, Abd ElHafeez S, Provenzano F, et al. The quality of reporting in clinical research: the CONSORT and STROBE initiatives. Aging Clin Exp Res 2013;25:9–15.

[49] Astephen Wilson JL. Challenges in dealing with walking speed in knee osteoarthritis gait analyses. Clin Biomech (Bristol, Avon) 2012;27:210–2. [50] Vulcano E, Lee YY, Yamany T, Lyman S, Valle AG. Obese patients undergoing total knee arthroplasty have distinct preoperative characteristics: an institutional study of 4718 patients. J Arthroplasty 2013;28:1125–9. [51] Dowsey MM, Liew D, Stoney JD, Choong PF. The impact of pre-operative obesity on weight change and outcome in total knee replacement: a prospective study of 529 consecutive patients. J Bone Joint Surg Br 2010;92:513–20. [52] Committee WotAAoHaKSEB. Obesity and total joint arthroplasty: a literature based review. J Arthroplasty 2013;28:714–21. [53] Ko S, Stenholm S, Ferrucci L. Characteristic gait patterns in older adults with obesity– results from the Baltimore Longitudinal Study of Aging. J Biomech 2010;43: 1104–10.