Non-invasive determination of coupled motion of the scapula and humerus—An in-vitro validation

doi:10.1016/j.jbiomech.2010.10.003

Journal of Biomechanics

Volume 44, Issue 3, 3 February 2011, Pages 408-412

https://doi.org/10.1016/j.jbiomech.2010.10.003 Get rights and content

Abstract

Measuring the motion of the scapula and humerus with sub-millimeter levels of accuracy in six-degrees-of-freedom (6-DOF) is a challenging problem. The current methods to measure shoulder joint motion via the skin do not produce clinically significant levels of accuracy. Thus, the purpose of this study was to validate a non-invasive markerless dual fluoroscopic imaging system (DFIS) model-based tracking technique for measuring dynamic in-vivo shoulder kinematics. Our DFIS tracks the positions of bones based on their projected silhouettes to contours on recorded pairs of fluoroscopic images. For this study, we compared markerlessly tracking the bones of the scapula and humerus to track them with implanted titanium spheres using a radiostereometric analysis (RSA) while manually manipulating a cadaver specimen’s arms. Additionally, we report the repeatability of the DFIS to track the scapula and humerus during dynamic shoulder motion. The difference between the markerless model-based tracking technique and the RSA was ±0.3 mm in translation and ±0.5° in rotation. Furthermore, the repeatability of the markerless DFIS model-based tracking technique for the scapula and humerus was ±0.2 mm and ±0.4°, respectively. The model-based tracking technique achieves an accuracy that is similar to an invasive RSA tracking technique and is highly suited for non-invasively studying the in-vivo motion of the shoulder. This technique could be used to investigate the scapular and humeral biomechanics in both healthy individuals and in patients with various pathologies under a variety of dynamic shoulder motions encountered during the activities of daily living.

Introduction

The shoulder joint, often referred to as the glenohumeral joint in most biomechanical studies, has the greatest range-of-motion of any joint in the human body. An in-depth understanding of shoulder joint biomechanics is instrumental for helping prevent shoulder injury and improving surgical treatment modalities for shoulder pathologies. However, due to its complicated anatomy and large range-of-motion, measuring the dynamic in-vivo kinematics of the shoulder joint is a challenging problem in the field of biomechanics.

Numerous techniques have been developed to study the in-vivo biomechanics of the human shoulder. A comprehensive review of techniques has been compiled by Hill et al. (2007). In a brief summary, in-vivo dynamic shoulder biomechanics have been investigated using the following modalities: electromagnetic tracking (McClure et al., 2001, Borstad and Ludewig, 2002, Crosbie et al., 2008, Ebaugh et al., 2005, Fayad et al., 2008), single plane fluoroscopy (Nishinaka et al., 2008, Kon et al., 2008), magnetic resonance imaging (Graichen et al., 2000a, Graichen et al., 2000b, Rhoad et al., 1998, von Eisenhart-Rothe et al., 2002, Hodge et al., 2001), radiostereometric analysis (RSA) (Hallstrom and Karrholm, 2006, Hallstrom and Karrholm, 2009, de Bruin et al., 2008), biplane radiography (Bey et al., 2008, Bey et al., 2007, Bey et al., 2010), and optical motion tracking (Inui et al., 2009, Dun et al., 2008, Murray et al., 2001, Fleisig et al., 2006, Barrentine et al., 1998). Additionally, a dual plane fluoroscopic imaging system (DFIS) (Li et al., 2004) has been used to report glenohumeral contact kinematics in healthy volunteers (Boyer et al., 2008) and in patients with total shoulder arthroplasty (Massimini et al., 2010) during quasi-static shoulder motion. However, the use of a DFIS for tracking the scapula and humerus during dynamic shoulder motion has not been assessed.

Therefore, the purpose of this study was to validate a non-invasive markerless model-based tracking technique using a DFIS to quantify the kinematics of the scapula and humerus during dynamic shoulder motion. A radiostereometric analysis (RSA) (de Bruin et al., 2008, Kedgley et al., 2009, Vrooman et al., 1998, Valstar et al., 2000) marker-based tracking technique was used as a reference for measuring shoulder kinematics during simulated shoulder motion of a cadaver specimen. Previously our laboratory has validated this technique in the knee (Li et al., 2008), spine (Wang et al., 2008) and ankle (Wan et al., 2006); and based upon these results, we hypothesized that the technique would track the scapula and humerus similarly to the RSA. In addition, the repeatability of the DFIS model-based tracking was assessed for the scapula and humerus in 6-DOF.

Section snippets

Specimen preparation

One male fresh-frozen cadaver torso (age, 30) with upper extremities intact was acquired. The specimen was stored at −20 °C until thawed at room temperature for testing. Titanium spheres 1/8 in. diameter were implanted into the scapula and humerus of both shoulders by an orthopaedic surgeon. For the scapula, a superior approach was utilized along the scapular spine. One sphere was implanted into the acromion, three spheres along the scapular spine and one sphere near the spinoglenoid notch. For

Comparison of the model-based with RSA

The data obtained from the dynamic non-invasive model-based tracking technique compared to the RSA marker-based technique are shown in Table 1. The average difference between the two techniques was 0.27±0.19 mm and 0.49±0.36° for all simulated motions of the scapula and humerus, respectively. The rotation rate (62°/s, 79°/s, 128°/s, and 180°/s) of the long axis of the humerus in abduction/adduction did not influence the magnitude of the difference between the two tracking techniques. However,

Discussion

This study presents the translation and rotation differences between a non-invasive markerless DFIS model-based tracking technique for measuring shoulder biomechanics with respect to a widely accepted RSA (de Bruin et al., 2008, Kedgley et al., 2009, Vrooman et al., 1998, Valstar et al., 2000) marker-based technique during simulated dynamic shoulder motion. The results show that this dynamic model-based tracking technique was close to the RSA within approximately ±0.3 mm in translation and ±0.5°

Conflict of interest statement

The authors of this manuscript have nothing to disclose that would bias our work.

Funding

Funding for this project were from unrestricted internal hospital research funds. No external funding sources were used for any part of this study.

References (43)

J.D. Borstad et al.
Comparison of scapular kinematics between elevation and lowering of the arm in the scapular plane
Clin. Biomech. (Bristol, Avon)
(2002)
M.J. Bey et al.
Measuring dynamic in-vivo glenohumeral joint kinematics: technique and preliminary results
J. Biomech.
(2008)
M.J. Bey et al.
In vivo measurement of subacromial space width during shoulder elevation: technique and preliminary results in patients following unilateral rotator cuff repair
Clin. Biomech. (Bristol, Avon.)
(2007)
P.J. Boyer et al.
In vivo articular cartilage contact at the glenohumeral joint: preliminary report
J. Orthop. Sci.
(2008)
P.W. de Bruin et al.
Image-based RSA: Roentgen stereophotogrammetric analysis based on 2D–3D image registration
J. Biomech.
(2008)
J. Crosbie et al.
Scapulohumeral rhythm and associated spinal motion
Clin. Biomech. (Bristol, Avon)
(2008)
A.G. Cutti et al.
Soft tissue artefact assessment in humeral axial rotation
Gait Posture
(2005)
D.D. Ebaugh et al.
Three-dimensional scapulothoracic motion during active and passive arm elevation
Clin. Biomech. (Bristol, Avon)
(2005)
F. Fayad et al.
Three-dimensional scapular kinematics and scapulohumeral rhythm in patients with glenohumeral osteoarthritis or frozen shoulder
J. Biomech.
(2008)
H. Graichen et al.
Glenohumeral translation during active and passive elevation of the shoulder—a 3D open-MRI study
J. Biomech.
(2000)

G. Wu

ISB recommendation on definitions of joint coordinate systems of various joints for the reporting of human joint motion—Part II: shoulder, elbow, wrist and hand

J. Biomech.

(2005)

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Citation Excerpt :
Therefore, there is not a direct relationship between voxel values of the radiography images and 2D projections of MRI. Glenohumeral (GH) kinematic measurement accuracy using CT-based 2D-3D registration has been studied (Bey et al., 2006; Giphart et al., 2012; Massimini et al., 2011; Zhu et al., 2012). However, validation of GH kinematic accuracy using MRI–based registration has never been done, to our knowledge.
Biplane 2D-3D registration approaches have been used for measuring 3D, in vivo glenohumeral (GH) joint kinematics. Computed tomography (CT) has become the gold standard for reconstructing 3D bone models, as it provides high geometric accuracy and similar tissue contrast to video-radiography. Alternatively, magnetic resonance imaging (MRI) would not expose subjects to radiation and provides the ability to add cartilage and other soft tissues to the models. However, the accuracy of MRI-based 2D-3D registration for quantifying glenohumeral kinematics is unknown. We developed an automatic 2D-3D registration program that works with both CT- and MRI-based image volumes for quantifying joint motions. The purpose of this study was to use the proposed 2D-3D auto-registration algorithm to describe the humerus and scapula tracking accuracy of CT- and MRI-based registration relative to radiostereometric analysis (RSA) during dynamic biplanar video-radiography. The GH kinematic accuracy (RMS error) was 0.6–1.0 mm and 0.6–2.2° for the CT-based registration and 1.4–2.2 mm and 1.2–2.6° for MRI-based registration. Higher kinematic accuracy of CT-based registration was expected as MRI provides lower spatial resolution and bone contrast as compared to CT and suffers from spatial distortions. However, the MRI-based registration is within an acceptable accuracy for many clinical research questions.
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Model-based tracking, using CT and biplane fluoroscopy, allows highly accurate quantification of glenohumeral motion and changes in the subacromial space. Previous investigators have used custom-built biplane fluoroscopes designed specifically for kinematic applications, which are available at few institutions and require FDA approval prior to clinical use. The aim of this study was to demonstrate the utility of an off-the-shelf clinical biplane fluoroscope for kinematic applications by validating model-based tracking for measurement of glenohumeral motion using an unmodified clinical system. Biplane images of each shoulder of a cadaver torso were acquired at various joint positions and during simulated movements along anatomical planes of motion. The pose of each humerus and scapula was determined using model-based tracking and compared to a bead-based gold standard. Error due to a temporal-offset between corresponding biplane images, characteristic of clinical biplane systems, was determined by comparison of measured and known relative position of 2 bead clusters of a phantom that was imaged while moved throughout the fluoroscopy image volume. Model-based tracking had global kinematic mean absolute errors of 0.27 mm and 0.29° (static), and 0.22–0.32 mm and 0.12–0.45° (dynamic). Glenohumeral mean absolute errors were 0.39 mm and 0.45° (static), and 0.36–0.42 mm and 0.41–0.48° (dynamic). The temporal-offset was predicted to add errors of 0.06–0.85 mm and 0.05–0.28° for cadaveric trials for the speeds examined. For defined speeds, sub-millimeter and sub-degree kinematic accuracy and precision were achieved using an unmodified clinical biplane fluoroscope for quantification of glenohumeral motion.

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Non-invasive determination of coupled motion of the scapula and humerus—An in-vitro validation

Abstract

Introduction

Section snippets

Specimen preparation

Comparison of the model-based with RSA

Discussion

Conflict of interest statement

Funding

Clin. Biomech. (Bristol, Avon)

J. Biomech.

Clin. Biomech. (Bristol, Avon.)

J. Orthop. Sci.

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Clin. Biomech. (Bristol, Avon)

Gait Posture

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