JIRA LINK: https://snomed.atlassian.net/browse/IHTSDO-955

Documentation review: JIRA IHTSDO-955 Remodel Talipes Valgus Documentation Review

Talipes_Combined Inception-Elaboration Phase v1.0.docx 

Amendment History

Review Timetable

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1 Glossary

1.1 Domain Terms

Talipes	A deformity of the foot and ankle,   usually congenital, in which the foot   is twisted and relatively   fixed in an abnormal position; any deformity of the   foot involving the talus Talipes is from the Latin talus   (ankle) + pes (foot); Pes refers to foot deformities. There is overlap in   usage of these Latin terms among the various descriptions.
Talipes Valgus Open	Eversion of the foot; the inner side alone of the sole resting on the ground; it is usually   combined with a breaking down of the plantar arch. Synonyms: pes abductus, pes pronatus, pes valgus
Talipes Varus Open	Inversion   of the foot, the outer side of the sole only touching the ground; usually   some degree of talipes equinus is associated with it, and often talipes cavus Synonyms: pes adductus, pes varus
Talipes Calcaneous Open	Sole of the foot faces   forward (dorsi-flexion) almost touching the anterior part of the leg, and the   strongly marked heel seems to be the direct extension of the leg; the axis of the calcaneus becomes vertically oriented; commonly   seen in poliomyelitis. FLEXION DEFORMITY   (Dorsi-flexion)
Talipes Calcaneocavus Open	Talipes   calcaneus and talipes cavus
Talipes Calcaneovalgus Open	Talipes   calcaneus and talipes valgus combined; the foot is dorsiflexed, everted, and   abducted; usually a positional deformity caused by intrauterine   "packaging"
Talipes Calcaneovarus	Talipes   calcaneus and talipes varus combined; the foot is dorsiflexed, inverted, and   adducted; less frequent deformity in which the foot points up on the   anterior-external side of the leg and the sole of the foot is facing outward
Talipes Cavus Open	An exaggeration of the normal arch of the foot; congenital and acquired forms   Synonyms: contracted foot, pes cavus, talipes plantaris; clawfoot
Talipes Cavovarus Open	Talipes cavus and talipes varus combined; a foot deformity characterized by an elevated   longitudinal arch caused by fixed plantar flexion of the forefoot; A cavo-varus foot that develops over time can indicate the presence of a   neurologic problem, the presence of a cyst, or possibly a tumor in the spinal   cord; seen in both pediatric and adult populations
Talipes Cavovalgus	Talipes   cavus and talipes valgus combined
Talipes Equinus Open	Permanent   plantar flexion of the foot so that only the ball rests on the ground; it is   commonly combined with talipes varus Equino- indicates the heel is elevated (like a horse's   hoof) . FLEXION DEFORMITY   (Plantar flexion)
Talipes Equinovalgus Open	Talipes equinus and talipes valgus combined; the foot is plantar flexed,   everted, and abducted; Malformation   of the foot evident at birth in which the heel is elevated like a horse's   hoof (equino-) and the heel is turned outward (valgus); Includes midfoot abduction, hindfoot valgus and equinus   contracture Synonyms: equinovalgus, pes equinovalgus
Talipes Equinovarus Open	Talipes equinus and talipes varus combined; the foot is plantar flexed,   inverted, and adducted the affected foot   appears rotated internally at the ankle - the foot points down and inwards   and the soles of the feet face each other; the   equinovarus deformity is classified into congenital and acquired. Acquired   equinovarus has neurogenic causes (e.g, poliomyelitis, meningitis, sciatic   nerve damage) and vascular causes (Volkmann Ischemic Paralysis). Congenital talipes   equinovarus (CTEV) also known as talipes equinovarus (TEV) is present at   birth; Equino- indicates the heel is elevated (like a horse's) and -varus   indicates it is turned inward Synonyms: clubfoot, equinovarus, pes equinovarus
Talipes Equinocavovarus	Talipes equinus and talipes varus    and talipes cavus combined
Talipes Planus	a condition in which the   longitudinal arch is broken down, the entire sole touching the ground. Synonyms: flatfoot, pes planus
Talipes   Transversoplanus	A deformity caused by sinking down of the transverse   arch of the foot; a broadened foot due   to spreading of   the anterior part   of the foot resulting from separation   of the heads of the metatarsal bones from each other. Synonyms: metatarsus latus, broad foot and   spread foot
Talipes Planovalgus	Combined planus and valgus; There is also a Flexible Pes Planovalgus (Flexible Flatfoot)...a physiologic variant consisting of a decrease in the medial longitudinal arch and a valgus hindfoot and forefoot abductions with weightbearing.
Positional Talipes	Positional talipes is a common foot condition in   newborn babies that may affect one or both feet. There are two forms (1)Positional Talipes Equinovarus (PTEV) in which   the foot is held pointing inwards towards the other foot and (2) Positional   Talipes Calcaneovalgus (PTCV) in which the foot is held turned outwards and   upwards.It can therefore be gently moved into a normal   position.   http://www.mcht.nhs.uk/EasysiteWeb/getresource.axd?AssetID=4568&filename=/A4_Physiotherapy_Advice_for_positional_talipes.pdf
Congenital   Vertical Talus	Same as   convex pes valgus or rocker bottom foot; consists of an irreducible dorsal dislocation   of the navicular on the talus producing a rigid flatfoot deformity; have   fixed hindfoot equinovalgus, rigid midfoot dorsiflexion and   forefoot abducted and dorsiflexed
XTE syndrome	Only noted   in one paper from 1970 with description: “The distinct features are congenital xeroderma with hyphidrosis, nail   abnormalities, hypoplasia of sweat glands (the epidermis otherwise normal), cleft palate, bilateral club foot   anomaly, hypoplasia of the ocular puncta leading to epiphora   and blepharitis, mild oligophrenia with abnormal electroencephalographic   changes. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1811831/

2 Introduction

2.1 Purpose

The purpose of this project is to understand and improve organization of concepts related to Talipes valgus and varus and the relationship to the more general concept “talipes”. Inconsistences were noted via a SIRS request (i.e. Request ID 636700)

SNOMED CT projects transition from Inception Phase à Elaboration Phase à Construction Phase à Transition Phase. This document combines the documentation of the Inception and Elaboration Phases.

The Inception Phase focuses on understanding the problem and its scope, identifying stakeholders and their requirements, and identifying risks.

The purpose of the Elaboration Phase is to develop, document and test one (or more) possible  technical solutions, and to reach a recommendation and provide a detailed specification of a preferred solution to be taken forward to the construction phase.

2.2 Audience and stakeholder domain

The audience for this document includes all standards terminology leaders, implementers and users but is especially targeted at those stakeholders from clinical practice who diagnose and treat patients with any form of “talipes” or deformities of the foot and ankle, especially those who practice orthopedics.

A further significant audience is the community of SNOMED authors that may be requested to help with implement of the recommended specification.

2.2.1 Input from stakeholders

Issues with Talipes concepts were reported via a SIRS request (ID = 636700) submitted on 11/8/15 where “Talipes valgus” was noted not to be a child of “Talipes”. Upon initial review, other Talipes concepts were found to obtain inconsistences with synonyms and relationships and most assigned as synonymous with congenital forms. Additionally, subtypes of Talipes were shown to be incomplete and poorly organized.

2.2.2 Degree of consensus on the statement of problem

Consensus was reached between the submitter/modeler and the editor reviewing the request. Review of the scientific literature confirmed that talipes concepts were indeed misrepresented and poorly modeled within SNOMED CT.

3 Statement of the problem or need

3.1 Summary of problem or need, as reported

The problem as reported was stated via SIRS request (ID =636700) where incorrect modeling of “Talipes valgus” was noted including the missing relationship to parent concept “Talipes” and improper modeling of congenital disorders.

3.2 Summary of requested solution

Posted comments in SIRS between the submitter/modeler and the editor confirmed that other Talipes concepts such as “Talipes varus” also had issues with its synonyms and relationships as well as did various subtypes of talipes. It was decided that a tracker item project needed to be created because several concepts required remodeling and resituation.

3.3 Statement of problem as understood

Upon review of the problem as submitted and requested as well as a literature review of Talipes-related disorders, it is understood that the representation of Talipes concepts is incorrect in their organization, their synonyms and their relationships. First and foremost, it is understood that there are insufficient definitions for these concepts which likely led to their current organization and modeling. It is understood that this project required the review and analysis of many more talipes concepts beyond the initial “talipes valgus” and “talipes varus”. The scope was expanded out of necessity due to the multiple issues with the organization and relationships of multiple talipes concepts after initial review.

3.4 Detailed analysis of reported problem, including background

Analysis of the problem starts with a definition of Talipes and its related concepts and a review of the concept model components.  Currently, there are 18 disorder concepts and 2 procedure concepts that contain the term “talipes” within its FSN or synonym. One concept “7037003 | XTE syndrome” appears to be unrelated as it is a skin disorder.

This review focuses on the organization and modeling of these concepts and how they are described by their FSNs and synonyms. One major observation is the current assumption that only congenital forms of talipes exist and there is reference to this with most of the FSNs and their synonyms. In some scientific reviews, this is presumed as the congenital forms are most common.  However, even though less common, various types of “talipes” may be acquired as a response to infection, trauma or neurologic abnormities. Note that the organization of all concepts under “deformity of the lower limb” should be reviewed and defined. For example,Talipes refers to deformities that involve both the ankle (from Latin “talus”) and foot (from Latin “pes”), whereas pes refers only to deformities of the foot. As noted in the recommended revisions, these latin terms are often used synonymously so many forms of talipes are also forms of pes.

3. 5 Subsidiary and interrelated problems

Additional work should be expanded to include all concepts under “deformity of the lower limb” and the separation of congenital and non-congenital forms of the various concepts that are currently included. Attention should be paid to the “pes” concepts that are currently included under both “deformity of the lower limb” and “deformity of foot” and how they are aligned as synonyms of talipes.

4 Risks / Benefits

4.1.1 Risks of not addressing the problem

Problems with the current concept model may result in issues with analysis and retrieval of data related to Talipes concepts based on the current logical definitions and incorrect meaning of the FSNs. Mapping errors may occur when migrating legacy code systems to SNOMED CT. Descriptions of the FSNs should be consistent among all Talipes concepts and not assume that they are synonymous with all congenital forms as the acquired forms of Talipes are currently not included within SNOMED CT. Currently “acquired pes” and “acquired pes cavus” exist within the current SNOMED CT corpus.

4.1.2 Risks of addressing the problem

There may be some risk to making concept model changes to those who have currently implemented SNOMED CT within their applications if relying on the description logic components but adding clarity and consistency to the various Talipes concepts should overall improve its implementation. Completion of this work highlights the need for additional work to address other modeling inconsistencies that may exist within the “deformity of lower limb” node.

5 Requirements: criteria for success and completion

5.1 Criteria for success/completion

Analysis of all Talipes concepts (n = 18 [disorders], n= 2 [procedures]) including their organization and modeling highlighting their correct text definition and subsequent logical definition. No changes were recommended for the 2 procedure concepts.

5.2 Strategic and/or specific operational use cases

The operational Use Case for this project would be the alignment of concepts with the Problem List

6 Solution Development

6.1 Initial Design

6.1.1 Outline of initial design

a. Extraction and breakdown of all Talipes concepts (n = 18 [disorders], n= 2 [procedures])

b. Organization of Talipes concepts through assignment of text definitions, identification of node placement and relationships and assignment of consistent FSNs and synonyms. The initial overview shows that there is an overlap of congenital talipes with the more general talipes concepts and no recognition of acquired talipes. The organization of talipes concepts, along with their descriptions, needs to be restructured consistent with their text definitions. Additional work will be needed to address other deformities of the lower limb that are out of scope of the Talipes concepts.

c. Communication of recommendations are listed in a table (Appendix A) within this document.

6.1.2 Significant design or implementation decisions / compromises

All Talipes concepts should be under a node named “Deformity of foot and ankle” based on concept text definitions. There are Talipes concepts currently within “deformity of lower limb” and others within “disorder of bone development”. Most of the Talipes concepts are within the subnode “deformity of foot” with no inclusion of the ankle deformity. Others are defined as a malrotation or anomaly instead of a deformity.

There is currently a concept “7037003 | XTE syndrome” that includes Talipes but very little documentation is available in recent literature years to support the stated description of the FSN.

Also noted, that some of the “pes” concepts are defined as a “deformity of lower limb” whereas others are defined as a “deformity of the foot”.  The concept “talipes calcaneus’ has a synonym of “pes calcaneus”. The “pes” concepts are not part of this project but most are properly called synonyms of the Talipes concepts based on research and are included in the included table (in Word) under the “synonym” column.

Currently, talipes descriptions between FSNs and synonyms are inconsistent.

A review of morphologic characteristics is important as some of the descriptions are poorly understood. For example 31668003 | talipes calcaneovalgus (disorder) contains a relationship of “13908001 | congenital turning upward (morphologic abnormality)”. What does this mean? The proper morphologic characteristics for this disorder include dorsiflexion, eversion, and abduction and relate to the position of the foot and ankle and not specifically to the bone as per the current grouping.

6.1.3 Evaluation of Design

The redesign and restructuring of the Talipes concepts was done based on text definitions and literature review with the inclusion of overlapping synonyms of “pes” concepts. The breakdown of concepts and their synonyms is included in the accompanying spreadsheet.                                            

 Talipes_v1.xlsx

The included Word document includes a table with the listing of definitive parents and characteristics related to each concept. It should be understood that all of the talipes concepts and recommended revisions apply to talipes concepts generally. Further breakdown into congenital and acquired forms should follow a similar modeling pattern.

As most of the Talipes descriptions include more than one morphologic abnormality of the foot and ankle, they will remain as mostly primitive concepts with the closest proximal primitive being the “398309008 | talipes” concept itself.

6.1.3.1 Exceptions and Problems

From the outset, the proximal primitive concept “398309008 | talipes” is not exclusively a congenital disorder.

6.1.3.2 Design Strengths

The redesign demonstrates consistency of the FSN and a broader inclusion of concepts to distinguish between congenital and acquired forms as well as the inclusion of overlapping “pes” synonyms. As the multiple types of talipes disorders have been described over many years, there are some authors who relate these disorders as congenital or even more broadly as “clubfoot” disorders, the recommended redesign includes the more precise definitions and acquired forms that have been described by orthopedic experts as far back as the year 1899 (REF Clarke)

6.1.3.3 Design Weakness

Due to the historical nature of the disease and the broad usage of the terms “talipes” and “pes” with their more frequent association with birth deformities, there may not be universal agreement of synonyms across the spectrum of talipes subtypes.

6.1.3.4 Design Risks

7 Recommendation

7.1.1 Detailed design final specification

The major design elements are a restructuring of the “talipes” concepts as well as overlapping “pes” concepts.

As per the accompanying table (Appendix a) of revisions, there is a breakdown of the current talipes concepts with the inclusion of missing types. Note that congenital and acquired forms of all these talipes concepts need to be amended separately in order to make the distinction between these two differing etiologies of the talipes deformity

The proximal primitive for these concepts would be the “398309008 | talipes” concept  that needs also needs correction to its model as it is not exclusively as congenital disorder but is more broadly known as a deformity of the foot and ankle. As stated previously, some nuances in the actual description of the disorders, such as “high arch” or “contracted foot” prevent the concepts from being fully defined and most will remain as primitive. Additionally, as noted in orthopaedic references, some of the “pes” concepts are commonly used as synonyms of the “talipes” concepts.

7.1.2 Iteration plan

The list of changes recommended for the Talipes concepts is detailed in Appendix A.  Correction of the parent concept “398309008 | talipes” would be a first step including the removal of its current parents “371521007 | disorder of bone development” and “66091009 | congenital disease” . In fact, the addition of a new concept “deformity of the foot and ankle” would be most appropriate or use of the current concept “449715001 | deformity of lower limb”. Currently, there is a concept “88562000 | acquired deformity of ankle AND/OR foot” as well as separate concepts for “299418001 | ankle joint deformity” and “229844004 | deformity of foot”.

Suggested concepts to be added:

deformity of the foot and ankle (disorder)

cavus deformity (morphologic abnormality)

acquired flexion deformity(morphologic abnormality)

8 Quality program criteria

8.1 Quality metrics

8.1.1 Quality metric 1

8.1.2 Quality metric 2

8.2 Use case scenarios

Beginning with text definitions of the various talipes concepts including the proximal primitive parent, will expose the needed corrections. “Talipes” is a deformity of the ankle and foot and currently no such parent exists. Several of the existing “talipes” concepts will need changes to their relationships and synonyms. All existing “talipes” concepts with congenital synonyms should be separated to align with acquired and congenital forms as subtypes to the overarching talipes forms. This will entail the creation of some new concepts but will allow for more correct definitions and organization of concepts. Initial correction to the proximal primitive parent “398309008 | talipes” would be best to begin with so subsequent subtypes can be properly ordered and classified.

8.3 Test cases

Same as previous paragraph

9 Project Resource Estimates

Project size:  Involves edits to approximately 25 concepts and the addition of 3 new concepts

As depicted in the table (Appendix A), the suggested changes are catalogued. As noted in the review, many of the talipes concepts use different models so each change will need to be tested individually.

9.1 Scope of construction phase

The scope is well defined and completed list of concepts and suggested changes are depicted in the table (Appendix A)

9.2 Projection of remaining overall project resource requirements

9.2.1 Expected project resource requirement category

Medium – based on analysis of the complexity of this project, the work may require up to 20 hours of editing in the authoring tool.

9.2.2 Expected project impact and benefit

Updated view of impact and benefit, organized by stage if the project is to be staged

With the expected edits, Talipes concepts will be better organized and include a more consistent concept model Some of the overlapping “pes” concepts will also benefit reorganization by their inclusion as synonyms with talipes concepts

9.2.3 Indicative resource estimates for construction, transition and maintenance:

Construction and transition phase: Approx 25 concepts to be edited; 3 new concepts to be authored

Maintenance phase: No additional requests are likely to be needed if all talipes subtypes are included in this project as well as their congenital and acquired forms.

Appendix A

Talipes revision

*terms in RED FONT are suggested to be added as new concepts or as FSNs

Open

From: http://medical-dictionary.thefreedictionary.com/talipes

Open

REF:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2759597/

http://www.orthobullets.com/pediatrics/4064/equinovarus-foot

http://www.healthofchildren.com/C/Clubfoot.html

https://www.vocabulary.com/dictionary/clawfoot

http://www.medicinenet.com/script/main/art.asp?articlekey=5710

http://kimfoot.com/pediatric-flatfoottalipes-calcaneovalgus/

http://www.healthofchildren.com/C/Clubfoot.html

http://www.mcht.nhs.uk/EasysiteWeb/getresource.axd?AssetID=4568&filename=/A4_Physiotherapy_Advice_for_positional_talipes.pdf

Clarke, James Jackson, Orthopaedic Surgery: A text-book of the Pathology and Treatment of Deformities, 1899