Patent Description:
<CIT> discloses a spinal-column arrangement estimation-apparatus, capable of estimating at least one of a Cobb angle and a rotation angle of spinal-column arrangement present inside a human body from an image representing a three-dimensional shape of a human body surface, thus facilitating diagnosis of scoliosis by a doctor, confirmation of a spinal-column by a determiner, etc., and reducing medical exposure by unnecessary X-ray inspection. The apparatus includes an image acquisition unit, configured to acquire an image representing a three-dimensional shape of a surface of a human body, a spinal-column arrangement estimation-unit, configured to estimate a spinal-column arrangement of the human body using accumulated data, and an angle calculation unit, configured to calculate at least one of a Cobb angle and a rotation angle from the estimated spinal-column arrangement.

<NPL>) discloses a calibration protocol, which uses off-the-shelf depth cameras and validated surface registration techniques to capture patient shape and pose, and learn statistical models of human shape and pose-dependent deformations.

Adolescent Idiopathic Scoliosis (AIS) is a prevalent disease that currently requires radiographic imaging for accurate diagnosis and treatment planning.

For diagnosis, monitoring, therapeutic planning, and epidemiologic analysis of scoliosis, images of the spine are required. Imaging modalities such as radiography, computed tomography (CT) and magnetic resonance (MR) imaging are commonly used, where radiography plays the primary role.

Beyond the health risks associated with repeated radiography, standard x-rays suffer from the inherent limitation of providing a two-dimensional projection of a three-dimensional structure, and a variety of trunk surface metrics have been devised to complement the Cobb angle in characterizing thoracic deformity.

Despite the prevalence of the disease, and the carcinogenic effect of repeated exposure to ionizing radiation, there is currently no accurate test for scoliosis outside of radiography. Accordingly, accurate non-invasive diagnostic technique would enable screening for scoliosis with less exposure to radiation.

A method, system and computer program product are provided as defined by the claims. The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope.

There is provided, in an embodiment, a method as defined in claim <NUM>.

There is also provided, in an embodiment, a system as defined in claim <NUM>.

There is further provided, in an embodiment, a computer program product as defined in claim <NUM>.

In some embodiments, said labelling is a scoliosis classification category selected from the group consisting of: main thoracic, double thoracic, double/triple major, and thoracolumbar/lumbar.

In some embodiments, said encoding is a low-dimensional encoding.

In some embodiments, said 3D body scan comprises at least one of: a point cloud, triangulated meshes, and splined surfaces.

Described herein are a system, method, and computer program product for predicting spinal shape of a human subject from a three-dimensional (3D) surface scan of the subject. In some embodiments, the prediction of the spine shape can involve applying one or more trained neural network algorithms.

In some embodiments, the present disclosure provides for detecting a spine shape of a human subject, based on a 3D surface scan of said subject (e.g., a depth map of the subject). In some embodiments, diverse technologies and technique from the field of three-dimensional (3D) graphics may be utilized to depict the human subjects. In some embodiments, these models can be represented in 3D coordinates that define the positions of surface elements representing the surface of an object in a 3D space, as elaborated further below.

In some embodiments, the present disclosure provides for analyzing the three-dimensional image to predict the spine shape of a human subject in a multi-step process which may involve diverse training methods of neural network algorithms.

In some embodiments, the present disclosure provides for generating a computerized parametrized three-dimensional (3D) body surface model which encodes various body type parameters, such as, e.g., those reflecting various skeletal and/or spinal deformities, such as scoliosis. The 3D model is trained, based, at least in part, on a training set comprising a plurality of 3D scans of subjects, wherein at least some of the 3D scans are of subjects having a skeletal deformity.

In some embodiments, the 3D model may be personalized for a specified target subject, by a process of optimization based on one or more 3D scans of the target subject. In some embodiments, at least some of the 3D scans are associated with various poses of the subject during the scan. In some embodiments, the optimization is performed by minimizing a loss function which registers the 3D model to the target 3D scans.

In some embodiments, the present disclosure may further provide for training a computerized skeletal estimation model to accurately estimate a skeletal shape of a subject from a 3D surface scan. The computerized skeletal estimation model is trained on a training set comprising body surface models of a plurality of subjects, and skeletal landmarks sets of the same subjects. In some embodiments, the training process of the skeletal estimation model may comprise a usage of a spine models defining the shape of the spinal cords of a human body. Thus, the training sets for the training stage of the skeletal estimation model may comprise a plurality of body surface models of human subjects, and spine models defining shapes of spinal cords. In some embodiments, the spine models may be utilized to train the skeletal estimation model to predict the spine shape in a given surface model of a human subject. In some embodiments, the training process to predict the spine shapes in a subject surface may involve optimization process utilized to identify the geometric relationship between at least one spine model and each body surface model in a given training set. In some embodiments, such a training process can train the skeletal estimation model to predict the spine shape in a body surface model given as an input at the inference stage.

In some embodiments, the trained computerized skeletal estimation model may be then applied to the personalized body model of the target subject, to estimate a skeletal shape of the target subject.

In some embodiments, the results may be used by clinicians to visualize skeletal body shape in 3D, for a fast, accurate, and safe diagnosis and treatment planning.

In some embodiments, the full analysis process for predicting the spine shape of a human subject may require a two-step process which involves, first, calculating a model of a parametrized three-dimensional body surface by applying the optimized and personalized neural network algorithm to a three-dimensional scan of a human subject. Then, applying the skeletal estimation model to the calculated three-dimensional body surface model, to predict the spine shape of that subject.

In some embodiments, the three-dimensional scan of a human subject utilized in the two-step process mentioned above, can be produced by an optical scanning system which requires no ionizing radiation, e.g., by depth cameras.

Scoliosis is the most common spinal deformity in adolescents, and in the United States affects up to <NUM>% of adolescents (about two million), <NUM>% adults (<NUM> million), and <NUM>% of the elderly.

The clinical definition of scoliosis is Cobb angle of above <NUM>° in the coronal plane. A more expressive classification system for describing scoliosis is the Lenke scale. In the simplest use case, Lenke classification divides scoliosis patients into six categories based on spine structure and function e.g. "Main Thoracic", "Double Major", "Triple Major", etc..

A parameterized model describes different members of a class (e.g. spine shapes) using a shared framework. A simple model of the human spine ignores morphology of individual vertebrae and instead merely describes the rigid body rotations between bones. By collecting a large representative training set and using dimensionality reduction, this method has been used to develop robust statistical models of scoliotic deformity with only five or ten parameters. An even simpler (and less descriptive) parameterization of the spine would be a one-dimensional curve that passes through the center of the vertebral bodies, though this would not even capture axial rotation.

In some embodiments, the present disclosure is based on the notion that surface body topography carries sufficient information to accurately estimate skeletal shape. A critical distinction is that the proposed methods seek to extract as much information as possible from surface scans by employing full-body modeling that accounts for and encodes pathological body types and variable postures.

Specifically, the methods proposed herein can provide an accurate estimate of an individual subject's spine pose, using shape parameters from a personalized body model. Furthermore, the present disclosure proposes a hypothesis that these parameters can be fitted to optical scans (e.g., depth clouds).

This proposal is divided into four sections:.

<FIG> is a flowchart of the functional steps in a method for estimating spinal shape of a subject from an optical scan, according to exemplary embodiments of the present invention.

At step <NUM>, a computerized parametrized three-dimensional (3D) body surface model is trained, based, at least in part, on a training set comprising a plurality of 3D scans of subjects. In some embodiments, at least some of the 3D scans are of subjects having a skeletal deformity.

In some embodiments, generating such a training set can be based on a computer animation-based model utilized to generate sets of three-dimensional images depicting human subjects in arbitrary poses. In some embodiments, graphics applications can utilize publicly available databases of three-dimensional human shapes for generating such a wide variety of human bodies in a variety of shapes at arbitrary poses.

In some embodiments, the representation of human subjects can be using skinned vertex-based models which accurately represent a wide variety of body shapes in natural human poses, e.g., Skinned Multi-Person Linear model (SMPL).

In some embodiments, other models which span variations in both body shapes and poses such as Shape Completion and Animation of People (SCAPE) can be used.

In some embodiments, the models utilized to define the training set, and or training sets, may be based on normal (e.g., bodies which don't manifest any pathologies) and bodies manifesting spine deformations and/or pathologies.

In some embodiments, other technologies and models that accurately represent a wide variety of body shapes in natural human poses can be used. , in some embodiments, a technology based on surface mesh may be used for that purpose. For example, the surface shape may be provided by collections of vertices, edges and faces which define the shape of a surface. In some embodiments, each surface element may be represented a three-dimensional coordinate system.

In some embodiments, diverse models may utilize different methods and technologies to express surface shapes and surface deformations. In some embodiments, these models may be based on a mesh of surface elements to represent the surface shape of a human subject. In some embodiments, such surface elements can be based on triangle deformations, wherein the surface is represented in diverse techniques such as, triangle mesh, vertex-based model, and the like.

In some embodiments, generating the training sets may also comprise using models of human subjects resulting from optical scans of both, bodies with no pathologies and bodies with pathologies.

In some embodiments, the training set and/or training sets with the images can be used to build input data comprising body type parameters for artificial neural network algorithm. In some embodiments, diverse techniques and neural network algorithms can be utilized as elaborated here below.

In <NPL>, it was shown the Standard Blend Skinning models from computer animation can be "corrected" with linear models learned from body scan data. The result is a state-of-the-art model that shows comparable or superior generalizability to previously published work and is significantly faster to render. The general expression for linear blend skinning is given by the following equations <MAT> <MAT> <MAT> where w is a blend weight for each vertex v over all K joints, and θ is the pose as in SCAPE. G<NUM> is the homogeneous transformation matrix that moves template vertex <MAT> to posed position Tv, and is formed by a series of local transformations around sequential joints with global coordinates J. R(ω) is the rotation matrix for angle-axis ω.

The innovation that Loper et al. introduce is to learn a set of body type parameters D and pose parameters Q to modify the template Tv before applying the blended pose transformation.

Here β is a low dimensional encoding of subject shape. The specific representation D is flexible. For example, a PCA, as elaborated further below, but this can be adapted to better suit the needs of a training set including deformity. In some embodiments, Q(θ) also has room for modification. In some embodiments, a linear combination of elements of the elements of R(θ) can be used but as noted in the literature, this too is open to experimentation.

SCAPE and SMPL are sophisticated models, but they both make an approximation that all humans deform analogously due to pose. This assumption is decidedly not true for scoliotic subjects. Indeed, measurements of trunk angle by scoliometer and the Adams bending test are predicated on research showing that scoliotic subjects do not deform like healthy subjects in a forward bending pose.

In some embodiments, to encode this relation, it may be necessary to update these deformation models to include a dependence on body type, such that pose deformations depend both on pose angles θ and body type β. For example, a linear blend of models weighted by body type parameters β: <MAT> where Pi is a matrix of learned parameters, and vec(R(θ)) is the column-stacked elements of all rotation's matrices in the model.

Given a training set of surface scans, model parameters P, w, T, and J can be learned by iteratively finding registrations that best match scans as well as model parameters. In some embodiments, this can be formulated as a minimization of an objective function across all subjects and all scans.

In some embodiments, other potentially nonlinear formulations for Q may be utilized. For each vertex, Qv(β,θ) is a <NUM>x<NUM> displacement vector. This function could for example be modeled with a simple feed-forward network. <MAT> wherein Wy, Uv are weight matrices, av, bv are bias vectors, and ϕ is a nonlinear function such as tanh. The specific architecture of the network may not be important.

In some embodiments, regardless of the specific formulation, this body model presents a significant innovation: Using body type parameters β that are specifically learned from pathologic subjects. The promise of this method is that, given a set of examples for training, it will be possible to model the expected deformations based on individual body type as characterized by β.

This, in turn, should also enable more accurate assessments of novel subjects: When performing nonrigid mesh registrations to fit optical scans of a novel subject, the registration will be guided by the deformations expected by the model. In this way, the registration process itself will perform the first step in characterizing scoliotic deformity.

As previously mentioned, part of a successful model can be properly defining β, individual subject shape in low dimensional space. In some embodiments, the simplest approach can be to project D into PCA space (principal component analysis) using all scoliotic and non-scoliotic subjects as the basis. This approach may probably work reasonably well but note that PCA is optimal for Gaussian variance while a training set of normal and scoliotic subjects is not expected to follow this distribution.

In some embodiments, a combination of PCA and Linear Discriminant Analysis (LDA) is proposed. In some embodiments, the idea is to concentrate deformity into a few parameters, while still allowing the model to generalize well across populations. To apply this technique to scoliotic body modeling, PCA will first be performed on subjects with less than <NUM>° spine curves, potentially including public training sets. The scoliotic population will then be projected onto the first few Principal Shape Components (PSC), corresponding to the axes of greatest variance in the normal population. These projections will be subtracted from the scoliotic population according to the Gram-Schmidt algorithm, leaving a residual characterized largely by scoliotic deformity.

In some embodiments, the scoliotic training set can then be labeled, for example into four simplified Lenke categories:.

In some embodiments, using the full Lenke classification would require bending radiographs, but the merged categories only account for <NUM>% of AIS patients. With these labels, the entire cohort can be processed with LDA to generate a set of coefficients representing scoliotic deformity. In this paradigm we anticipate defining β as perhaps the first four PCA PSCs as well as four classes for LDA.

<FIG> is an illustration of low-dimensional surface parameterizations. Surface scan <NUM> is received from an existing dataset (e.g., <NPL>). A nonrigid mesh registration to surface scan <NUM> may then be generated, followed by a low-dimensional PCA representation <NUM> using <NUM> PSCs. Finally, s semantic encoding <NUM> is created, similar to, e.g., <NPL>).

<FIG> shows a registered surface mesh <NUM>, a PCA representation <NUM>, and a PCA residual <NUM>. In some embodiments, the PCA residual <NUM> can be utilized as inputs to LDA decomposition. In some cases, for this non-pathologic subject, the residuals are largely symmetric.

In some embodiments, full-body surface representation can be provided by a system employing an array of depth cameras. In some embodiments, such a system can utilize the images captured by the depth camera to produce a multi-dimensional surface representation of the optically scanned body. In some embodiments, such can be based on surface mesh which represent the body in vertices, edges and faces which define the shape of the body surface.

In some embodiments, the vertices of the surface representation are defined in a unified coordinate system. In some embodiments, the unified coordinate system can provide the positions of the vertices for generating a vector representation of the human subjects.

In some embodiments, the specific technology used to collect surface scans is not important, and several viable options exist. The CAESAR training set was collected using laser scanners, while other systems employ stereo photogrammetry. For example, the Temporal 3dMDBodyTM scanner may be employed. Such a scanner provides full-body surface scans captured in about <NUM>.

In some embodiments, additional, or alternative categories may be utilized for labeling the training set.

In some embodiments, the scanned bodies can be utilized for generating training sets for a neural network algorithm to be able to identify a specific pathology for a scanned body provided as an input at the inference stage.

In some embodiments, at step <NUM> in <FIG>, the parametrized body model generated in step <NUM> is optimized to a target subject. In some embodiments, one or more target 3D scans of a target subject are received. The model generated at step <NUM> is then optimized and personalized to the target subject based on the target 3D scans, via a training process which minimizes a loss function which registers the body surface model to the target 3D scans. At the conclusion of step <NUM>, a personalized target body surface model of the target subject is generated.

In some embodiments, target subjects may be scanned in a variety of poses, resulting in a series of surface scans (for example point clouds, triangulated meshes, splined surfaces, etc).

In some exemplary embodiments, an MRI or CT scanners can be used as a scanning mechanism. In some embodiments, such MRI or CT scanners can provide cloud of data points representing volumetric data or "voxel" sets. In some embodiments, the point cloud can be represented in a unified coordinate system. For example, such a coordinate system can have an x-axis, a y-axis and a z-axis coordinate system. In some other possible embodiments such a coordinate system may be an axel-axis system.

In some embodiments a registration process can align the surface scans within a unified coordinate system. For example, point clouds from depth cameras or from a CT scanning can be brought into a unified coordinate system. Such a unified coordinate system can be utilized for comparing and measuring body poses of scanned bodies with a body surface models. In some embodiments, the scanned bodies may be labeled according to the poses of the human subjects.

In some embodiments, classifying the target subject amounts to an optimization problem similar to the process described by Loper et al. The difference is that here, body parameters β specifically capture differences due to pathology, and influence the pose dependent deformations Q(β,θ). The optimization problem can be written as <MAT> where S is a scan, Ts is the model mesh for a given scan, θs is the pose for a given scan, ρ is a robust distance metric such as Geman-McClure, and λ, µ are regularization weights. The last term assumes that body parameters are zero centered, and many other regularizations and penalty terms are possible (surface normal, contact with floor surface, color, etc).

In some embodiments, given proper initialization, this optimization can be performed with gradient descent algorithms. Body parameters β are those which best describe the subject, including pathologic deformations across all scans. For example, a scoliotic patient could be scanned both standing upright but also in the Adams forward bend posture; solving Eq. (<NUM>) would provide the parameters that best fit both scans, thereby providing a holistic model of the patient.

<FIG> shows the steps (from left to right) in a ample registration with initialization and optimization of pose and body type.

Having a parametric model of deformity will enable objective classification of body type in a way not currently possible. This would allow physicians to compare patient populations between hospitals. Perhaps even more significantly, an objective measure of body shape may prove instrumental in evaluating treatment options, such as varying surgical options or different bracing techniques as mentioned above.

Equation (<NUM>) is agnostic to the source of surface data. In some embodiments, a low-cost and potentially portable system comprised of one or more depth cameras controlled by a computer that can record, and process optical scans can be used. In preliminary testing we have employed three Intel Realsense D435 cameras on a single host with a multithreaded application.

Cameras are first calibrated to transform point clouds into a unified coordinate system. This can be accomplished by recording a calibration target (e.g. sphere) in many mutually visible locations. Rigid transformation between coordinate systems can be computed with SVD. Novel subjects can then be scanned in multiple poses and their body parameters found as described above.

At step <NUM>, a computerized skeletal estimation model is trained to estimate skeletal (e. , spinal) shape. In some embodiments, the training is based on a training set comprising (i) body surface models of a plurality of subjects, and (ii) skeletal landmarks sets of said plurality of subjects.

In some embodiments, the process of identifying the spine shape of a human subject from a three-dimensional image may be by utilizing at least one spine models representing spine deformations. In some embodiments such spine models can represent specific deformations, shapes, and/or skeletal structures. In some embodiments, these spine models can be utilized to train the skeletal estimation model to predict the spine shape of a human subject in the three-dimensional image surface model of a human subject given as an input at the inference stage.

In some embodiments, more than one spine model may be used, wherein each spine model may represent spine deformations and/or skeletal structure of a specific spinal deformity.

In some embodiments, the spine models may be defined with positions of vertebral landmarks designed to depict the shape of the spinal cord. In some embodiments, the vertebral landmarks can form a specific spine shape which can be associated with specific spinal deformity. In some embodiments, the vertebral landmarks positions can be identified by a unified coordinate system. For example, the landmark positions can be expressed with coordinate values.

Previous sections have demonstrated how parametric models can describe human surfaces and spine shape. The present disclosure now proposes, in some embodiments, a statistical model that can determine the relationship between these two surface body shape and skeletal (e.g., spinal) shapes.

In some embodiments, a triangle deformation model similar to SCAPE may be formulated, except in this case, the triangulated mesh is not a watertight shell. Each edge on the back of the template mesh is connected to each vertebral landmark of the template spine, giving a sort of clustered pyramid for each vertebra. The deformation model from template edges V* to model edges V is simply: <MAT> <MAT> where Lf is a 3x3 deformation matrix for face f. The β coefficients are the coefficients after mapping D into low dimensional space as described above.

With reference to <FIG>, in some embodiments, utilizing a unified coordinate system and techniques which are based on surface mesh can allow expressing areas on the body surface and the spine models on one coordinate system. In some embodiments, utilizing one unified coordinate system can allow determining the geometric relationship between the spine model and the surface of a human subject.

Given a training set of aligned surface meshes and skeletal landmarks (<FIG>), L is found by minimizing the squared error between the model edges Vf and the measured edges.

Once this model has been trained, it is possible to predict skeletal shape of novel subjects. For example, a patient could be scanned with depth cameras and body surface modeled as described above. Then skeletal landmarks can be estimated using Eq. (<NUM>).

In some embodiments, an EOS™ slot scanner may be used to collect radiographic measures of spine shape. In some embodiments, several depth cameras may be positioned around the scan area such that they can record the human subject simultaneously with the radiography scanning, i.e., in a temporally-aligned fashion. In some embodiments, surface models may be fitted to the optical scan as described above. Parametric spine models can be constructed by fitting statistical models to the radiographic image. Four-spine modeling can be sufficient to use the semi-automated sterEOS reconstructions provided by EOS Imaging. Once a training set is collected with both these parametric models in a shared coordinate space it is possible to learn the statistical relation between them, as described above.

At step <NUM>, the trained skeletal estimation model is applied to the calculated target body surface model of the target subject, to estimate a skeletal shape of said target subject.

In many skeletal pathologies, functional disability may be less of a concern than patient self-image. Surgeons may measure the success of an operation based on radiographic measures (e.g. coronal curve correction) while patients see the external expression. Unfortunately, there are few objective measures of surface deformity, and even fewer 3D parameters.

In this proposal body type coefficients β can be read directly as a measure of deformity, as these values correspond to LDA classifications of the pathologic residual (after subtracting most PCA variance from normals). For example, the proposed LDA formulation for scoliotic patients is derived from the well documented and widely accepted Lenke classification system. It is therefore possible that physicians will feel comfortable interpreting and adopting these parameters.

More directly, the present disclosure proposes that these models can be employed in patient assessment. Body parameters will be used to track changes in patient surface shape after treatment, for example bracing or surgery. Furthermore, these parameters will be used as an objective measure of three-dimensional deformity by correlating with subjective appraisal by patients and clinicians. For example, it may be possible to find which model parameters correlate with improved patient reported surgical outcomes as measured by e.g. TAPS, or to develop a replacement questionnaire using 3D models in place of 2D sketches.

In some embodiments, the pathology type associated with the spine shape can be utilized to assess the skeletal shape.

<FIG> shows a block diagram of an exemplary system according to an embodiment of the present invention. <FIG> is a block diagram which in some embodiments, can be designed as a computer program product implementing at least some of the process and/or methods disclosed by the present disclosure.

System <NUM> as described herein is only an exemplary embodiment of the present invention, and in practice may have more or fewer components than shown, may combine two or more of the components, or a may have a different configuration or arrangement of the components. The various components of system <NUM> may be implemented in hardware, software or a combination of both hardware and software. In various embodiments, system <NUM> may comprise a dedicated hardware device, or may form an addition to/or extension of an existing device.

System <NUM> may store in storage device <NUM> software instructions or components configured to operate a hardware processor <NUM> comprising such as hardware processor (also "hardware processor," "CPU," or simply "processor). In some embodiments, the software components may include an operating system, including various software components and/or drivers for controlling and managing general system tasks (e.g., memory management, storage device control, power management, etc.) and facilitating communication between various hardware and software components.

In some embodiments, the software components of the system <NUM> may comprise an operating system, including various software components and/or drivers for controlling and managing general system tasks (e.g., memory management, storage system control, power management, etc.) and facilitating communication between various hardware and software components.

In some embodiments, system <NUM> may comprise a hardware processor <NUM>, a communications module <NUM>, memory unit <NUM>, storage device <NUM>, a user interface <NUM>, skeletal pose evaluating module <NUM>, classifier <NUM>, neural network module <NUM>, and image data module <NUM>.

In some embodiments, the image data module <NUM> can be configured to process the received image data. In some embodiments, such image data can depict a human subject. In some embodiments, the image data can depict a scanned human subject in a three-dimensional fashion. In some embodiments, the image data module <NUM> may be configured to store the image data in a memory unit <NUM>.

In some embodiments, the image data module <NUM> may operate the communications module <NUM> for the purpose of receiving images from an external third-party device. In some cases, such the third-party device can be a computerized device designed to send, provide, and receive image data. In some embodiments, the communications module <NUM> may also be utilized by the system <NUM> for one or more communication tasks. Such communication tasks may be sending information and/or data to other computerized devices, communicate over a network , receive information or data, and the like.

In some embodiments, the image data module <NUM> may be configured to communicate with the user interface <NUM> for the purpose of displaying the images depicting human subjects to a user operating the system <NUM>. Such images can be three-dimensional scans of bodies, body surface models, and the like.

In some embodiments, the user interface <NUM> may be configured to communicate with a display device (not shown) and display the images. In some embodiments, the user interface <NUM> can provide with one or more graphic interfaces designed to receive instructions and/or commands from a user. In some embodiments, such instructions can be provided by an input device such as mouse device, keyboard device, and the like.

In some embodiments, the image data module <NUM> may also be configured to receive computer instructions to administrate the images and/or the three-dimensional scans. In some embodiments such instructions can be received the memory unit <NUM>. In some embodiments, the instructions can be received from an input device, e.g., keyboard or a mouse input device, controlled by a user.

In some embodiments, the image data module <NUM> may be configured to communicate with external computerized devices for the purpose of receiving the image data from a third-party entity such a remote computer or a remote database. In some embodiments, the image data module <NUM> may configured to communicate with digital storage mediums for the purpose of receiving image data. Such a storage medium can be SD storage, an external storage medium designed to store digital files, and the like.

In some embodiments, classifier <NUM>, is a machine learning classifier which may be configured to be trained on a training set comprising a plurality of images depicting human subjects and labels, and classify each human subject in an image into specified classes according to one or more classification techniques and/or algorithms. In some embodiments, such classes may be spine deformities, poses if human subjects, and the like.

In some embodiments, the neural network module <NUM> is a module operated by system <NUM> and designed to communicate with a neural network layer which include the learning layers according to one or more neural network techniques and/or algorithms. In some embodiments, the neural network module <NUM> may be configured to communicate with a neural network algorithm for the purpose of learning from a training set.

In some embodiments, the neural network module <NUM> can be configured to utilize calculation procedures, and or formulas for the purpose of the training. In some embodiments such formulas, can be optimization formulas, objective functions, loss functions, and the like.

In some embodiments, the neural network module <NUM> can be configured to communicate with the skeletal pose evaluating module <NUM> for the purpose of estimating the spine deformities from a scan of a human subject. In some embodiments, the neural network module <NUM> can applied to a three-dimensional scan of a human subject residing in the skeletal pose evaluating module <NUM> for predicting the spine shape. In some embodiments, such a three-dimensional scan may be an optically scanned human subject.

In some embodiments, system <NUM> may operate the skeletal pose evaluating module <NUM> to receive image data from the image data module <NUM> and communicate with an external service neural network module <NUM>.

In some embodiments, the neural network module <NUM> may utilize one or more neural network techniques and/or algorithms to determine the spine shape. In some embodiments, the spine shape may be determined, based on previously conducted training sessions configured to train the neural network module <NUM> to detect the spine shape of a body in a three-dimensional scan.

A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device having instructions recorded thereon, and any suitable combination of the foregoing. Rather, the computer readable storage medium is a non-transient (i.e., not-volatile) medium.

Computer readable program instructions for carrying out operations of the present invention may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages.

These computer readable program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

Claim 1:
A method comprising:
generating (<NUM>) a parametrized three-dimensional (3D) body surface model, which encodes at least one body type parameter representing a skeletal deformity;
receiving one or more target 3D scans of a target subject;
optimizing (<NUM>) said body surface model with respect to said one or more target 3D scans, based, at least in part, on minimizing a loss function which registers said body surface model to said target 3D scans, to calculate a target body surface model of said target subject;
training (<NUM>) a skeletal estimation model, based, at least in part, on a training set comprising:
(i) body surface models of a plurality of subjects, and
(ii) skeletal landmarks sets of said plurality of subjects; and
applying (<NUM>) said trained skeletal estimation model to said calculated target body surface model of said target subject, to estimate a skeletal shape of said target subject,
wherein at least some of said one or more target 3D scans are labelled with a pose of said subject associated with a respective target 3D scan,
wherein generating the parameterized 3D body surface model comprises training said 3D body surface model based on a training set comprising a plurality of 3D scans of subjects, wherein at least some of said 3D scans are of subjects having said skeletal deformity, and
wherein at least some of said plurality of 3D scans are labelled with said skeletal deformity.