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A classification for congenital limb malformations
ORIGINAL COMMUNICATIONS A classification for congenital limb malformations The classification for congenital limb malformations adopted by the American Society for Surgery of the Hand. the International Federation of Societies for Surgery of the Hand. and the International Society of Prosthetics and Orthotics is presented. This method groups similar patterns of deficiencies according to the parts that have been primarily affected by certain embryological failures. whether the insult involv'es a total part (skeletal and soft tissue) or only the dermomyofascial structures . The main categories of this classification are (I) failure offormation of parts. (II) failure of differentiation (separation) ofparts. (III) duplication. (IV) overgrowth. (V) undergrowth. (VI) congenital constriction band syndrome. and (VII) generalized skeletal abnormalities . The rationale and method of use of the classification are discussed. This method has been tested and used in a variety of centers and has been found to be properly conceived and practical.
Alfred B. Swanson, M.D., F.A.C.S. Grand Rapids, Mich.
International agreement on a classification for congenital limb malformations or deficiencies long has been sought. The classification adopted by the American Society for Surgery of the Hand and the International Federation of Societies for Surgery of the Hand is practical and useful to differentiate the types of deformities seen in the upper limbs. Use of it can aid us to identify, categorize, and readily retrieve specific diagnoses of congenital malformations. Its adoption by agencies reporting birth anomalies could help to establish a true incidence of these deformities.
Previous classifications In the past the use of various Greek and Latin names to describe common deficiencies has only described an anomaly in another language . Terms such as adactyly, arachnodactyly, brachydactyly, brachyphalangia, c1inod~ctyly, camptodactyly, ectrodactyly, ectrosyndactyly, macrodactyly, polydactyly, symbrachydactyly, syndactyly, hypodactyly, arthrogryposis, cleft hand, split hand, lobster-claw hand, central aplasia, perodactyly, peromanus, peropus, perochirus, talipomanus, clubhand, meromelia, hemimelia, amelia, ectromelia, phocomelia, hypertrophy, macro dactyli a , arachnodactylia, gigantism, proximal femoral focal deReceived for publication Sept. 23. 1975. Revised for publication April 9, 1976. Reprint requests: Alfred B. Swanson , M.D.• F.A.C.S. , Blodgett Medical Building, Plymouth and Wealthy Sts .• Grand Rapids, Mich . 49506.
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July. 1976
ficiency, intercalary, c1inarthrosis, and synostosis have been used to describe various anomalous conditions and are confusing to most clinicians. I, 2 The general problems of designing a useful classification have been described well in the publications of Frantz and O'Rahilly ,3 Barsky ,4 Patterson ,5 Entin ,6. 7 Hall, 8 and Swanson and others. 9·25 The difficulty always has been to develop a classification between one so general that it is valueless and one so detailed that its use becomes impossible. Committees of the American Society for Surgery of the Hand and the International Federation of Societies for Surgery of the Hand have developed a classification which was proposed and published in Surgical Clinics of North America in October, 1968, by Swanson, Barsky and Entin 24 under the title, "Classification of limb malformations on the basis of embryological failures."7 The classification currently proposed has evolved from this work.
An ideal classification A workable classification should employ a simple, easily remembered, descriptive terminology. It should allow the recording of common clinical entities with minimal confusion, but yet permit the full categorization of complex cases. An ideal classification could be made by grouping deformities according to the causative factor, but the cause of many of these defects still is obscure. Since enough basic information has been collected to group cases according to the parts that have been affected primarily by certain embryological failures, we chose this method in the classification sys-
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tern we are presenting. This method of grouping cases first was proposed in 1964 by Swanson 19 and it appears to be practical in avoiding much of the confusion that is caused by the many forms that now are commonly in use. Preliminary' considerations Study of the early development of limbs in the human embryo demonstrates that limb differentiation occurs in a definite sequential order. The upper and lower limbs are recognizable first as small buds of tissue on the lateral body wall at the fourth week after ovulation. These buds grow and differentiate rapidly in a proximodistal sequence in the ensuing 4 weeks; the arm and the forearm, for example, appear before the hand. The skeletal elements of the limbs are found within these limb buds and the mesenchymal condensations soon chondrify in a definite order and ossification follows. The differentiation of the soft tissue elements of the limb usually follows in an order similar to that of the skeletal elements, unless a disorder of development or differentiation occurs. Most limb defects occur during the embryonic phase of differentiation; environmental factors inhibit the rate of orderly differentiation of the part which is changing most rapidly and whose cellular components are highly sensitive at that particular moment. In animal experiments certain common congenital defects can be predicted consistently by disturbing the embryo at precise stages of development. 26 It is possible, for example, to observe the clinical manifestations of arrest of development at the time during the embryonic stage and at the specific limb site at which the defect occurred. The severity and the place of insult on the evolving limb bud can be compared to that of abscess formation in adult tissues. In the abscess there is an area of central destruction surrounded by an area of cellular infiltration resulting in scar tissue formation and structural deformity. The same destructive process occurring in embryological life, before structural formation has occurred, certainly would lead to disorganization of the developing tissue about the area of destruction within the organization of the limb mesenchyme. The various clinical pictures of limb deficiencies are felt to represent varying degrees of destruction within this organization of the limb mesenchyme. The time of the insult occurrence, the sequeptial development of the part, and the location of the destructive process are important and will determine the type of ensuing deformity. The most common environmental agents responsible for the production of these defects may include anoxia,
Classification for congenital limb malformations
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irradiation, antivitamins, hormones, drugs, and some viral infections. 27·35 The mother's ability to metabolize or handle these agents and the individual's genetic pattern can be important factors in modifying the final configuration of the deformity. The anatomist, the biochemist, the embryologist, and the geneticist, along with the clinician, continue to report important advances in understanding these problems. . Classification of congenital limb deficiencies Although the embryological insult to the limb is usually not so specific as to result in a sharp line of demarcation, certain similar patterns of deficiencies can be grouped. These patterns therefore can make up categories of a classification of defects. Our experience in classifying 300 patients with congenital upper limb malformations has shown us that the cases may involve a total part or both skeletal and associated soft tissue parts of the limb, or they may involve only the dermomyofascial structures. 25 A classification which would consider all limb elements, both skeletal and soft tissue, would best answer the needs of the clinician and surgeon; those deformities involving only soft tissue deficiencies are considered to be milder manifestations of general deficiency patterns. For example, when parts of the thumb only are deficient, this deformity should be categorized under radial longitudinal deficiencies (the so-called radial "clubhand" or "radial hemimelia" in the old classification), as it represents a mild deficiency of the preaxial or radial radial of the limb. Based on these general principles, the defects can be categorized as follows: I. II. III. IV. V. VI. VII.
Failure of formation of parts (arrest of development). Failure of differentiation (separation) of parts. Duplication. Overgrowth (gigantism). Undergrowth (hypoplasia). Congenital constriction band syndrome. Generalized skeletal abnormalities.
This classification takes note of the similarities in certain large groups of deformities. Subclassification of these categories recognizes the basic differences and expresses the degree of severity of the type of deformity. As an example, the so-called radial "clubhand" is a failure of radial longitudinal formation; in addition to the fact that the radius is absent either partially or totally, the condition can be associated also with hypoplasia or aplasia of the thumb, carpal bones, or muscu-
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UPPER LIMB (Ul) SHOULDER (Sh)
----II TOTAL
---1
ARM (Arm)
FOREARM (Fo)
lOWER LIMB (ll)
~PElVIS (Pel)
TOTAL UPPER 1/3 ~ MIDDLE 1/3 THIGH (Thigh) LOWER 1/3
t--1 ----1 TOTAL 1/3 UPPER MIDDLE 1/3 LOWER 1/3
LEG (Leg)
TOTAL PARTIAL
r-----TARSAL (Ta)
METACARPAL (Me)
TOTAL PARTIAL
r-----METATARSAL (Mt)
PHALANGEAL Ph
TOTAL PARTIAL
t-----PHALANGEAL (Ph)
CARPAL (Ca)
----1 ( )----1
Fig. 1. Failure of formation of parts, transverse . The digits are named by expressing the anatomical level at which the limb terminates. Attention is drawn to an oddity which apparently occurs: total absence of the shoulder or hemipelvis and all distal elements would be a transverse defect. However , if only a portion of the shoulder or hemipelvis were absent, the deficiency would be of the longitudinal type. lature on the preaxial or radial side of the limb. Each group can be subclassified into its degrees of severity, as desired for completeness. Experience with this classification has shown that it can function successfully in categorizing malformations. It has been used in a variety of clinics including efforts to program it for the computer. A very comprehensive clinical test was carried out by Flatt29 to determine its usability; it was his conclusion that the proposed classification was a properly conceived and practically usable classification for congenital anomalies of the limb. this classification was designed primarily for use with the hand anomalies. However, it also lends itself to use for the entire upper limb and for the lower limb as well. During 1974 the effectiveness of the new system of classification of congenital limb deficiencies was assessed by 15 specialized child-amputee centers in the United States and Europe which collectively classified some 400 congenital limb deficiencies. After resolving some relatively minor problems enc.ountered in this trial, the new system was endorsed for international use. It also was proposed to the World Health Organization for inclusion in the revision of the standard nomenclature.
Fig. 2. Category I: Failure of formation of parts, transverse. The cross-hatched area represents the area of embryological insult.
Failure of formation of parts. Rationale of categorization. The Subcommittee on Nomenclature and Classification of Congenital Limb Deficiency, * of the International Society for the Prosthetics and Orthotics , which met in Dundee in 1973 and Montreux in 1974, recommended an enlargement and refinement of Category I (failure of formation of parts) to define accurately the skeletal deficiencies seen in juvenile amputee clinics . 12, 14 Attention was given to the four basic categories proposed in the FrantzO'Rahilly3 work: terminal transverse or longitudinal and intercalary transverse or longitudinal. Unanimity of opinion was reached concerning the terminal transverse condition , that is, those presenting a congenital amputation-type stump. However, the existence of true intercalary deformities was questioned and, only after long discussion, agreement was reached that true intercalary deficiencies rarely, if ever, existed. It was postulated that all "phocomelias" or "intercalary deficiencies" in fact have some terminal manifestations, either a carpal or tarsal aberration, a defect of finger or *H. J. B. Day (England); H . L. Henkel (West Germany); Leon M. Kruger (U .S.A.); Douglas W. Lamb (Scotland); Ernest Marquardt (West Germany); Ross Mitchell (Scotland) ; Alfred B. Swanson (U .S.A.); H. G. Willert (West Germany); Hector Kay ( U.S.A.).
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Classification for congenital limb malformations
CD
CD
UPPER LIMB (U L)
SCAPULA (Sc) TOTAL OR PARTIAL
CLAVICLE (CI) TOTAL OR PARTIAL
ILIUM (Il) TOTAL OR PARTIAL
LOWER LIMB (LL) ISCHIUM (Is) TOTAL OR PARTIAL
PUBIS (Pu) TOTAL OR PARTIAL
FEMUR (Fern) TOTAL OR PARTIAL
HUMERUS (Hu) TOTAL OR PARTIAL RADIUS (Ra) TOTAL OR PARTIAL
ULNA (UI) TOTAL OR PARTIAL
TIBIA (Ti) TOTAL OR PARTIAL
FIBULA (Fib) TOTAL OR ·PARTIAL
METACARPALS (Me) TOTAL OR PARTIAL
2 3 4
RAYS
METATARSALS (Mt) TOTAL OR PARTIAL
2
3
4
RAYS
PHALANGES (Ph) TOTAL OR PARTIAL
RAYS
PHALANGES ) Ph) TOTAL OR PARTIAL
2
3
4
2
RAYS
3
11
4
Fig. 3. Failure of formation of parts, longitudinal. The names of all bones totally or partially absent are named. Any bone not named is presumed present. A, Upper limb. B. Lower limb
Fig. 4. Category I: Failure of formation of parts, longitudinal. A. Phocomelia represents the most profound expression of longitudinal failure of formation of parts. The cross-hatched area represents the maximal area of embryological insult. However, some defects of the terminal limb are also always present. B. Clinical example illustrating a complete phocomelia. Note the associated hand anomalies.
toe, or a deficiency of muscle, tendon, skin, or nail; this suggested that these so-called "intercalary" defects in reality are variable degrees of longitudinal deficiencies. It was decided that, except for the true transverse deficiencies (congenital amputation stumps), all others are a manifestation of some longitudinal aberration in the formation of parts; thus, even that condition described as "hypoplasia" of a limb or skeletal element, in reality, has a longitudinal failure in the sense
of the long axis of each bone. Similarly, although "phocomelia" presents a major manifestation of failure of formation in the long bones, there is also a lesser and perhaps minimal failure in the peripheral elements which, although present, are never truly normal. This concept of progressive longitudinal reduction can be carried to a point where only a single digital remnant of a limb remains and, ultimately, to the situation in which even this vestigial peripheral element failed to
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Fig. S. Category I: Failure of formation of parts, longitudinal-radial: radial ray deficiencies or radial deficiency (or the so-called "radial clubhand " or "radial hemimelia"). A, Diagram illustrating the areas of embryological insult. Band C, Clinical photograph and radiogram of a radial ray deficiency.
form-the true amelia. This, therefore , might be considered a maximum longitudinal deficiency, although presenting as a transverse-type defect. For simplicity of designation, however, amelia might best be categorized as a transverse deficiency. The category of failure of formation of parts is that group of congenital deficiences noted by failure or arrest of formation of the li mb either complete or partial . Based on the previous line of reasoning, it is divided into two types: transverse and longitudinal. The transverse defects would encompass all so-called congenital amputation-type conditions and include what heretofore were referred to as terminal transverse deficiences. The second major group, longitudinal deficiencies , then in effect would encompass all deficiencies which are not in the transverse category . This category is seen frequently in amputee centers because of the need for rehabilitation with prostheses. TRANSVERSE DEFICIENCIES. Transverse deficiencies present as amputation type stumps and are classified by naming the level at which the remaining limb terminates, it being understood that all elements distal to the level named also are absent (Fig. 1). The deficiencies in this group represent the so-called "congenital amputations" (a poor term, not to be confused with intrauterine amputations, which are not deficits of the limb), ranging from aphalangia to amelia. The stump usually is well padded with soft tissue and may show rudimentary digits or a dimpling at the end of the stump. It represents an arrest of formation in the limb anlage (Fig.
2). One of the most common types of transverse deficiency is at the level of the upper third of the forearm or "short below-elbow" defect. LONGITUDINAL DEFICIENCIES. All skeletal limb deficiencies in this category , other than the transverse type, are placed arbitrarily in the longitudinal group . In identifying longitudinal deficiencies, all completely or partially absent bones are named. Any bones not named as being absent are understood to be present (Fig. 3). The deficiencies in this group reflect the separation of the pre- and postaxial divisions in the limb and include longitudinal failure of formation of entire limb segments (phocomelias) or of either the radial, central, or ulnar components of the limb. The most profound expression of the longitudinal reduction of the limb is phocomelia , which demonstrates the proximal-distal failure of development. Phocomelia may be classified as: (1) complete phocomelia: the hand is attached directly to the trunk , demonstrating the failure of development of the proximal segments of the limb (Fig . 4); (2) proximal phocomelia: the proximal segment (arm) is mi ssing and the hand is attached to the forearm which is attached to the trunk; (3) distal phocomelia: the forearm is absent and the hand is attached directly to the arm. 3 The absence of parts or deficiencies on the radial (preaxial) side of the limb may vary from deficient thenar muscles to a short, floating thumb, and from deficient carpals, metacarpals, and radius to the classical so-called "clubhand" that we prefer to describe
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Classification for congenital limb malformations
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Fig. 6. Category I: Failure of formation of parts, longitudinal-central. A. Diagram illustrating the areas of embryological insult. Note the absence of the middle ray and associated failure of separation of parts between the little and ring fingers resulting in a cleft hand with syndactylysm of the little and ring fingers. B. Clinical example of a central deficiency or left hand.
as radial ray deficiencies or radial deficiency (Fig. 5). These deficits may involve the areas of the radius and thumb, radius only, or thumb only. In central ray or central (carpal and/or digital) deficiencies, the second, third, and fourth of the so-called "central" rays of the hand, which are noted to be embryologically differentiated at a separate time from the radial and ulnar rays, may be involved (Fig. 6). The middle finger or metacarpal may be missing as in the so-called "lobster-claw" hand. In severe central deficiencies, the central digits may be reduced to nubbins. In the severe case the defect may result in complete suppression similar to a transverse arrest resulting in aphalangia. In deficiencies of the ulnar side of the limb, the little or ring fingers may be deficient with or without associated deficiencies in the ulna and carpal bones (Fig. 7). These deficits may involve the areas of the ulna and fingers, ulna only, or fingers only. We describe these longitudinal arrests of formation of parts as ulnar ray deficiencies or ulnar deficiencies. Failure of differentiation (separation) of parts. Failure of differentiation or separation of parts is that category in which the basic units have developed but the final form is not completed. The homogenous anlage divides into separated tissues of skeletal, der-
Fig. 7. Category I: Failure of formation of parts, longitudinal-ulnar. Ulnar ray deficiencies or ulnar deficiency (or so-called "ulnar clubhand" or "ulnar hemimelia").
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Fig. 8. Category II: Failure of differentiation of parts . A. Synostosis. elbow and proximal radius and ulna . Band C. Syndactyly. D. Example of failure of differentiation of skin, muscle, ligaments, and capsular structures of the hand resulting in so-called arthrogrypoid hand.
Volume 1 Number 1 July, 1976
momyofascial, or neurovascular elements found in normal limbs, but fails to completely differentiate or separate. For example these defects may include the following: A. Shoulder 1. Undescended shoulder 2. Absence of pectoral muscle(s) B. Arm 1. Elbow synostosis C. Forearm 1. Soft tissues 2. Synostosis a. Proximal radius/ulna (Fig. 8, A) b. With/without radial head dislocation D. Hand 1. Carpal a. Deformities b. Synostosis 2. Metacarpal a. Deformities b. Synostosis 3. Digital a. Deformities b. Symphalangism c. Syndactyly (Fig. 8, B and C) 1. Simple 2. Complicated a. Soft tissue 1. Nails (synonychia) 2. Other b. Skeletal 1. Fusions a. Phalanges (side to side) b. Acrosyndactyly c. Apert's syndrome 2. Disarray 3. Brachysyndactyly (short webbed fingers) d. Contracture secondary to failure of differentiation of muscle, ligaments and capsular structures 1. Soft tissue a. Thumb web space b. Arthrogryposis (Fig. 8, D) c. Camptodactyly (flexion contracture of little finger) d. Trigger digit 2. Skeletal, a. Clinodactyly (lateral deviation or displacement due to asymmetrical abnormalities of the digits).
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Fig. 9. Category III: Duplications resulting from splitting of the original embryonic parts: A and B. phalanges, and C. socalled "mirror hand."
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Fig. 10. Category IV: Overgrowth (gigantism). A, Diagram showing involvement of the third and second digits. B, Example of involvement of the second digit.
Duplication. Duplications of parts probably occurs as a result of a particular insult to the limb bud and ectodermal cap at very early stages of their development so that splitting of the original embryonic part occurs (Fig. 9). These defects may range from polydactyly to twinning or mirror hands and can be classified as follows: A. Skeletal 1. Humerus 2. Radius 3. Ulna 4. Carpals 5. Metacarpals 6. Phalanges B. Skin and nails C. All tissues 1. Whole limb 2. Partial limb 3. Polydactyly a. Radial b. Central c. Ulnar 4. Mirror hand. Overgrowth (gigantism). The whole limb may be affected by overgrowth. Some cases appear to be due to skeletal overgrowth with normal-appearing soft parts. Others show excess fat; lymphangioma or angioma
Fig. 11. Category V: Undergrowth (hypoplasia). This can be a local or more generalized involvement. Diagram illustrates the involvement of the entire hand.
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Fig. 12. Category VI: Congenital constriction hand syndrome. A, At the middle of the arm . B, At the hand resulting in pseudosyndactylysm . Most frequently the web spaces are intact and the fused mass of digital substance is the result of intrauterine healing of the necrotic areas involving the digits. This must not be confused with true syndactylysm resulting from failure of differentiation of parts .
Fig; 13. Category VII: Generalized skeletal defects illustrated by (A) achondroplastic extremity and (B) typical hand of diastrophic dwarf.
may be present. In digital gigantism the abnormality usually is greatest at the periphery. Deformities may increase secondarily due to asymmetrical growth of the part (Fig. 10). Gigantism may involve the following: (I) arm; (2) forearm; (3) hand; (4) digit. Undergrowth (hypoplasia). Undergrowth, or hypo-
plasia, denotes defective or incomplete development of the parts. This may be manifested in the entire extremity or its divisions (Fig. II) . Hypoplasia may be used as a supplemental description for remaining skeletal elements in cases of failure of formation of parts (Category I). However, this category should be represented
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separately in this classification system because of the prevalence of this condition. Hypoplasia may involve any of the following systems: A. Skin and nails B. Musculotendinous C. Neurovascular D. Extremity I. Arm 2. Forearm 3. Hand a. Whole hand b. Metacarpals (brachymetacarpia) c. Phalanges (brachyphalangia). Congenital constriction band syndrome. Focal necrosis along the course of the limb may happen in the postembryonic stage of development. The annular constriction bands or rings are a result of an area of necrosis involving the superficial tissues which heals as a circular scar (Fig. 12, A). When these constriction bands are severe, they may result in intrauterine gangrene and true fetal amputations may occur. The occasional associated syndactyly in these cases may be the end result of the intrauterine healing process (Fig. 12, B). The necrosis of tissue and its resultant fusion of parts is not unlike an untreated third degree burn with bridges of scar. The syndactyly and confused anatomical arrangements of parts found in these patients may be the result of a healing necrotic infarct occurring during the stage of separation of parts. Controversy has existed as to whether this is an intrinsic or extrinsic defect. Amniotic bands have been implicated as the cause of these defects; others feel that the amniotic bands are secondary to the healing limb injury. Generalized skeletal abnormalities. Defects in the hand may be a manifestation of a generalized skeletal defect, such as appears in dyschondroplasia, achondroplasia, Marfan's syndrome (with arachnodactyly), diastrophic dwarfism, etc. (Fig. 13).
How to use the classification Each patient reviewed should be recorded on a silhouette drawing which shows an outline of the limb and of the skeletal parts such as shown in Figs. 14 and 15. Shading out of absent parts and labeling of associated defects can facilitate the subclassification of deficits. Further description of deficient parts can be facilitated by anatomical divisions of the limb into shoulder girdle, arm, forearm, and hand. These can be broken down further into carpus, digits (I, 2, 3,4, 5), phalanges (1, 2, 3), proximal, middle, and distal parts of long bones. Description of muscle loss, skin and nail variations, nerve, motor, or sensory deficits, associated
HAND SURGERY
contractures or relaxations, and such conditions as the subluxation or dislocation of joints, range of motion of joints, vascular anomalies associated with spinal, visceral, or other soft tissue defects can be listed for completeness. Occasionally the insult to the limb may result in apparent mixed involvement. As an example, the failure of formation may be manifested as an almost transverse arrest of the entire hand with only rudimentary radial and ulnar digits present (Fig. 16). Where there is variable involvement of the rays of the hand, the judgment of the clinician will be required to categorize these relatively rare cases appropriately. He should place the particular patient into the category which represents the predominant deficiency. The need for this type of categorization does not arise very frequently, in our experience. It was decided to eliminate Greek and Latin terms, such as "peromelia," "ectromelia," "hemimelia," and" meromelia," and to attempt to describe deficiencies in the simplest yet most precise language which would be understandable by all the English-speaking world and be easily translatable into other languages. However, there should be no objections to retaining some existing terms in common use in the subclassification of these conditions. Cases of transverse arrest of the limb may be categorized easily by using the conventional amputation levels. As an example, a certain type of congenital transverse arrest of development of the forearm might also be described as a "transverse arrest, short below-elbow type."
General rules in the use of the classification of congenital limb deficiencies. Abbreviations. In anatomical description and classification the use of abbreviations and acronyms frequently provides a system of shorthand which is of value as long as the meanings of the terms employed are essentially self-evident. Abbreviation terms for the anatomical components are suggested in Fig. 3. When one or more metacarpals or metatarsals and the corresponding phalanges are completely absent, simply refer to them as rays. Terms such as "transverse" and "longitudinal" can be abbreviated with little danger of confusion. For example: TIL and T/R for transverse left and right, respectively; and L/L and L/R for longitudinal left and right. Similarly when two sequent bones are affected to the same degree, they could be combined in the classification. Thus a combined longitudinal deficiency of the right upper limb, humerus total, radius total, carpus partial, metacarpal I, 2 total, phalanges, I, 2 total, could more simply be written L/R, Hu and Ra total, Ca partial, Rays I, 2 total.
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Classification for congenital limb malformations
Supplemental conditions. Always put absences first followed by supplemental conditions, e.g., T/R, Ca partial; with hypoplasia of Ra and U 1 . In hypoplasia associated with transverse deficiencies as above, name hypoplastic leg or forearm bones, since one may be affected but not the other. In partial absence of long bones in longitudinal deficiencies, identify the approximate amount of missing segment, e.g., L/L, Hu partial (prox. 3/4). Order of classification. In classifying longitudinal deficiencies always proceed from proximal to distal,
e.g., L/R, Hu partial (prox. 3/4); VI total; Ca partial. Surgery. Although the surgical conversion of congenital deficiencies is not a basic classification item, information on such conversion may be included on the description-classification form as supplemental data as follows. (1) In cases of surgical amputation to provide a better limb remnant for prosthetics fitting,. e.g., a Syme's type amputation in the case of a complete absence of the fibula, a horizontal line (-) in red pencil or ink should be made on the form at the appropriate level. (2) In cases of reconstructive surgery, e.g., in the
DESCRIPTION - CLASSIFICATION FORM/CONGENITAL SKELETAL LIMB DEFICIENCIES - UPPER LIMB CLINIC Grand Rapids NAME.""N""or",m;!-a*:B",'"-----""""H""''''''''''',,.-- SEX~ CASE NO. _ _ _DATE~ RACE CaucasjanBIRTH DATE~X-RAYS DATE~LACE OF BIRTH '"'('""c"",t""y'}----r::(c::::ou:::nT.t,..y'=-}-=--=--=--=--=--=-("'s_t'::.at~e,...}KEY 1. SCAPULA
2·. 3. 4, 5. 6. 7. 8. 9. 10 .
CLAVICLE SHOULDER JOINT f - - - - - HUMERUS ELBOW JOINT ULNA RADIUS WRIST JOINT CARPALS METACARPALS 11. PHALANGES
- - - - - - - 1 Hemivertebrae D-4. u-6;
10 ribs left
9
_ _ _ _ _ _ _ 10
Carpal bones not cgmpletely ossifiE.d 10
_ _ _ _ _ _ _ 11
FUNCTIONAL AMPUTATION LEVEL CLASSIFICATION .RIGHT : L/·"'Rc-.""R-a-pa-r7' tiC-a '-l;-'CC'-a-p-a-:rt-:-ia""'I-'Me ray 1; Ph ray 1.
19
CLASSIFICATION, LEFT
: L/l Ra complete' Ca partjal' fic ray 1 ~ Ph ray 1.
Fig. 14. Limb silhouette (A) and clinical photograph (B) illustrating a case of radial ray deficiency (or socalled "radial-clubhand" or "radial hemimelia" in the old classification). This defect is in Category I of the classification: longitudinal failure of formation of parts .
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HAND SURGERY
DESCRIPTION - CLASSIFICATION FORM/CONGENITAL SKELETAL LIMB DEFICIENCIES - LOWER LIMB
_==____===_ _ -,==__
CLINIC Grand Rapids NAME vN",a;.;:nC~y~Fi·
8. 9. 10.
11.
12.
SACRUM INNOMINATE HIP JOINT FEMUR PATELLA KNEE JOINT TIBIA FIBULA ANKLE JOINT TARSALS METATARSALS PHALANGES
SublllXed
1--------1 2________
~
DATE ~ (state)
ANCt-iALl ES OTHER THAN OF LIMBS
ta ) liS
_ __ _ _ _ 10
10 - - - - - - - - - -
-----------~1
11--------
FUNCTIONAL AMPUTATlDN LEVEL _~L~ tYre
FUNCTI ONAL AMPUTATION lEVEL
Cl'SSIFIC'.TI0N, RIGHT: L/R Fib total; Mt 5 total ;Ph 5 total
1 2 - - -- -- -_ _
CLASSIFICATION, LEFT:
Fig. 15. The lower extremity can be affected by the same range of defects as the upper extremity. Limb silhouette (A) and clinical photograph (B) illustrating a case of fibular ray deficiency (or so-called "fibular hemimelia"
in the old classification) . This is in Category I of the classification: longitudinal failure of formation of parts.
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Classification for congenital limb malformations
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It is vitally important that a uniform classification be adapted throughout the world in order to facilitate the monitoring of the congenital malformations, to permit comparisons of incidence between the different areas, and to assist in the research regarding possible etiological factors, prevention, and selection of most efficacious methods of management. These are mandatory for the establishment of national registries for collection of baseline data and for establishment and coordination studies carried on by individuals and institutions. The author wishes to thank Dr. Genevieve Swanson, Shirley Furgerson, and Richard Scherzer for their assistance in the preparation of this paper.
REFERENCES I. Boyes, J. H.: Bunnell's surgery of the hand, ed. 5, Phila-
Fig. 16. Occasionally the insult to the limb may result in apparent mixed involvement. As an example, the failure of formation of parts may be manifested as an almost transverse arrest of the hand with only rudimentary digits present.
pollicization of the index finger in certain cases of radial ray deficiency, the operation should be indicated by an (X), again in red pencil or ink, at the area involved. (3) An osteotomy would be shown by an appropriate marking in red pencil or ink. A problem common to all classification systems is that radiograms taken when a child is very young may not reveal bones which are not ossified yet; thus early diagnosis should be considered tentative and subject to revision when the child is followed with radiograms at a more mature age. Another problem encountered is that some bone remnants are unidentifiable. It is recommended that the classifier use his best judgment as to what is present or missing but indicate by a (?) that this is a presumption and not necessarily an exact identification.
Comment The Classification of Congenital Malformations presented has received international approval and should facilitate the coding of these patients. We urge every clinic and institution concerned with the management of congenital malformations of the upper extremity to test the validity and practicality of this classification. This is an important undertaking and it requires the utmost international cooperation.
delphia, 1970, J. B. Lippincott Company. 2. Kelikian, H.: Congenital deformities of the hand and forearm, Philadelphia, 1974, W. B. Saunders Company. 3. Frantz, C. H., and O'Rahilly, R.: Congenital skeletal limb deficiencies, 1. Bone Joint Surg. 43A: 1202, 1961. 4. Barsky, A. J.: Congenital anomalies of the hand and their surgical treatment, Springfield, Ill., 1958, Charles C Thomas, Publisher. 5. Patterson, T. J. S.: Congenital deformities of the hand. Hunterian Lecture delivered at Royal College of Surgeons of England, April, 1959. 6. Entin, M. A.: Reconstruction of congenital abnormalities of the upper extremities, J. Bone Joint Surg. 41A: 681, 1959. 7. Entin, M. A., Barsky, A. J., and Swanson, A. B.: Committee report to American Society for Surgery of the Hand, 1966. 8. Hall, C. B., Brooks, M. B., and Dennis, J. F.: Congenital skeletal deficiencies of the extremities: Classification and fundamentals of treatment, J. A. M. A. 180: 590, 1962. 9. Aitken, G. T.: Proximal femoral focal deficiencydefinition, classification, and management, in Proximal femoral focal deficiency-a congenital anomaly, NAS Publication 1734, 1969, pp. 1-22. 10. Burtch, R. L.: Nomenclature for congenital skeletal limb deficiencies, a revision of the Frantz and O'Rahilly classification, Artif. Limbs. 10: 24, 1966. 11. Henkel, H. L., and Willert, H. G.: Dysmelia, a classification and a pattern of malformation of congenital limb deficiencies, J. Bone Joint Surg. SIB: 399, 1969. 12. International Society for Prosthetics and Orthotics, Working Group: The proposed international terminology for classification of congenital limb deficiencies, London, 1975, Spastics International Medical Publications in association with W. Heinemann Medical Books, Ltd., and 1. B. Lippincott Company. 13. Kanavel, A. B.: Malformations of the hand, Arch. Surg. 24: 153 and 282,1932.
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14. Kay, H. W.: A proposed international terminology for the classification of congenital limb deficiencies, Orthop. Pros. J. 28: 33-48, 1974. 15. Kelikian, H., and Doumanian, A.: Congenital anomalies of the hand, J. Bone Joint Surg. 29A: 1002 and 1249, 1957. 16. O'Rahilly, R.: Morphological patterns in limb deficiencies and duplications, Am. J. Anat. 89: 135, 1951. 17. Saunders, J.: Inductive interplay during limb development. Lecture delivered before Annual Meeting of Juvenile Amputee Clinic Chiefs (Subcommittee on Child Prosthetics Problems NAS-NRC), Chicago, Jan. 1966. 18. Swanson, A. B.: Unusual anomalies in the upper extremity, Orthop. Pros. J. 14: 47, 1960. 19. Swanson, A. B.: A classification for congenital malformations of the hand, N. J. Bull. Acad. Med. 10: 166, 1964. 20. Swanson, A. B.: Phocomelia and congenital limb malformations. Surgical reconstruction and prostehtic replacement, Kobe J. Med. Sci. 2 (Suppl.): Dec., 1965. 22. Swanson, A. B.: Classification of limb malformations on the basis of embryological failures: A preliminary report, N. Y. Univ. Inter.-C1in. Info. Bull. 6: I, 1966. 23. Swanson, A. B.: Severe congenital anomalies of the upper limb, considerations for classifications and treatment in Cramer, L. M., and Chase, R. A., editors: Symposium on the hand, Vol. 5, St. Louis, 1971, The C. V. Mosby Company, pp. 132-149. 24. Swanson, A. B., Barsky, A. J., and Entin, M. A.: Classification of limb malformations on the basis of embryological failures, Surg. C1in. North Am. 48: 1169, 1968. 25. Swanson, A. B., and Fujiwara, A.: Review of 300 cases of congenital malformation. Unpublished data from Michigan Area Amputee Clinc, 1963.
26. Duraiswami, P. K.: Experimental causation of congenital skeletal defects and its significance in orthopaedic surgery, J. Bone Joint Surg. 34-A: 646, 1952. 27. Bagg, H. J.: Etiology of certain congenital structural defects, Am. J. Obstet. Gynecol. 8: 131, 1924. 28. Birch-Jensen, A.: Congenital deformities of the upper extremities, Copenhagen, 1950, Ejnar Munksgaards, Forlag. . 29. Flatt, A. E.: A test of a classification of congenital anomalies of the upper extremity, Surg. C1in. North Am. 50: 509, 1970. 30. Frantz, C. H.: Increased incidence of malformed infants in West Germany during 1959-62, III. Med. J. 123: 27, 1963. 31. Hepp, 0.: Frequency of the congenital defectanomalies of the extremities in the Federal Republic of Germany, N. Y. Univ. Inter. C1in. Inform. Bull. 1: 3, 1962. 32. Jentschura, G., Marquardt, E., and Rudel, E. M.: Malformation and amputations of the upper extremity: Treatment and prosthetic replacement, New York, 1967, Grune & Stratton, Inc. 33. Taussig, H. B.: A study of the German outbreak of phocomelia, J. A. M. A. 180: 1106, 1962. 34. Warkany, J., and Schraffenberger, E.: Congenital malformations induced in rats by roentgen rays, Am. J. Roentgenol. Radium Ther. Nucl. Med. 57: 455, 1947. 35. Willert, H. G., and Henkel, H. L.: Klinik und pathologie der dysmelie: die fehlbildungen an den oberen extremitaten bei der thalidomid-embryopathie, Heidelberg, New York, 1969, Springer-Verlag.
From Kidd, John: On the adaptation of external nature to the physical condition of man, London, 1852, H. G. Bohn, p. 27. Quoting from Galen, The use of various parts of the body: Nor have we yet enumerated the most important of those priveleges which the hand imparts to man. With this he weaves the garment that protects him from the summers heat or winters cold; with this he forms the various furniture of nets and snares, which give him dominion over the inhabitants as well of the water as of the air and earth; with his hand he constructs the lyre and lute and the numerous instruments employed in the several arts of life; with the hand he erects altars and shrines to the immortal gods; and lastly by means of the same instrument, he bequeaths to posterity, in writing, the intellectual treasures of his own divine imagination; and hence we, who are living at this day, are enabled to hold converse with Plato, and Aristotle, and all the venerable sages of antiquity.
Alfred B. Swanson, M.D., F.A.C.S. Grand Rapids, Mich.
International agreement on a classification for congenital limb malformations or deficiencies long has been sought. The classification adopted by the American Society for Surgery of the Hand and the International Federation of Societies for Surgery of the Hand is practical and useful to differentiate the types of deformities seen in the upper limbs. Use of it can aid us to identify, categorize, and readily retrieve specific diagnoses of congenital malformations. Its adoption by agencies reporting birth anomalies could help to establish a true incidence of these deformities.
Previous classifications In the past the use of various Greek and Latin names to describe common deficiencies has only described an anomaly in another language . Terms such as adactyly, arachnodactyly, brachydactyly, brachyphalangia, c1inod~ctyly, camptodactyly, ectrodactyly, ectrosyndactyly, macrodactyly, polydactyly, symbrachydactyly, syndactyly, hypodactyly, arthrogryposis, cleft hand, split hand, lobster-claw hand, central aplasia, perodactyly, peromanus, peropus, perochirus, talipomanus, clubhand, meromelia, hemimelia, amelia, ectromelia, phocomelia, hypertrophy, macro dactyli a , arachnodactylia, gigantism, proximal femoral focal deReceived for publication Sept. 23. 1975. Revised for publication April 9, 1976. Reprint requests: Alfred B. Swanson , M.D.• F.A.C.S. , Blodgett Medical Building, Plymouth and Wealthy Sts .• Grand Rapids, Mich . 49506.
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ficiency, intercalary, c1inarthrosis, and synostosis have been used to describe various anomalous conditions and are confusing to most clinicians. I, 2 The general problems of designing a useful classification have been described well in the publications of Frantz and O'Rahilly ,3 Barsky ,4 Patterson ,5 Entin ,6. 7 Hall, 8 and Swanson and others. 9·25 The difficulty always has been to develop a classification between one so general that it is valueless and one so detailed that its use becomes impossible. Committees of the American Society for Surgery of the Hand and the International Federation of Societies for Surgery of the Hand have developed a classification which was proposed and published in Surgical Clinics of North America in October, 1968, by Swanson, Barsky and Entin 24 under the title, "Classification of limb malformations on the basis of embryological failures."7 The classification currently proposed has evolved from this work.
An ideal classification A workable classification should employ a simple, easily remembered, descriptive terminology. It should allow the recording of common clinical entities with minimal confusion, but yet permit the full categorization of complex cases. An ideal classification could be made by grouping deformities according to the causative factor, but the cause of many of these defects still is obscure. Since enough basic information has been collected to group cases according to the parts that have been affected primarily by certain embryological failures, we chose this method in the classification sys-
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Volume 1 Number 1 July, 1976
tern we are presenting. This method of grouping cases first was proposed in 1964 by Swanson 19 and it appears to be practical in avoiding much of the confusion that is caused by the many forms that now are commonly in use. Preliminary' considerations Study of the early development of limbs in the human embryo demonstrates that limb differentiation occurs in a definite sequential order. The upper and lower limbs are recognizable first as small buds of tissue on the lateral body wall at the fourth week after ovulation. These buds grow and differentiate rapidly in a proximodistal sequence in the ensuing 4 weeks; the arm and the forearm, for example, appear before the hand. The skeletal elements of the limbs are found within these limb buds and the mesenchymal condensations soon chondrify in a definite order and ossification follows. The differentiation of the soft tissue elements of the limb usually follows in an order similar to that of the skeletal elements, unless a disorder of development or differentiation occurs. Most limb defects occur during the embryonic phase of differentiation; environmental factors inhibit the rate of orderly differentiation of the part which is changing most rapidly and whose cellular components are highly sensitive at that particular moment. In animal experiments certain common congenital defects can be predicted consistently by disturbing the embryo at precise stages of development. 26 It is possible, for example, to observe the clinical manifestations of arrest of development at the time during the embryonic stage and at the specific limb site at which the defect occurred. The severity and the place of insult on the evolving limb bud can be compared to that of abscess formation in adult tissues. In the abscess there is an area of central destruction surrounded by an area of cellular infiltration resulting in scar tissue formation and structural deformity. The same destructive process occurring in embryological life, before structural formation has occurred, certainly would lead to disorganization of the developing tissue about the area of destruction within the organization of the limb mesenchyme. The various clinical pictures of limb deficiencies are felt to represent varying degrees of destruction within this organization of the limb mesenchyme. The time of the insult occurrence, the sequeptial development of the part, and the location of the destructive process are important and will determine the type of ensuing deformity. The most common environmental agents responsible for the production of these defects may include anoxia,
Classification for congenital limb malformations
9
irradiation, antivitamins, hormones, drugs, and some viral infections. 27·35 The mother's ability to metabolize or handle these agents and the individual's genetic pattern can be important factors in modifying the final configuration of the deformity. The anatomist, the biochemist, the embryologist, and the geneticist, along with the clinician, continue to report important advances in understanding these problems. . Classification of congenital limb deficiencies Although the embryological insult to the limb is usually not so specific as to result in a sharp line of demarcation, certain similar patterns of deficiencies can be grouped. These patterns therefore can make up categories of a classification of defects. Our experience in classifying 300 patients with congenital upper limb malformations has shown us that the cases may involve a total part or both skeletal and associated soft tissue parts of the limb, or they may involve only the dermomyofascial structures. 25 A classification which would consider all limb elements, both skeletal and soft tissue, would best answer the needs of the clinician and surgeon; those deformities involving only soft tissue deficiencies are considered to be milder manifestations of general deficiency patterns. For example, when parts of the thumb only are deficient, this deformity should be categorized under radial longitudinal deficiencies (the so-called radial "clubhand" or "radial hemimelia" in the old classification), as it represents a mild deficiency of the preaxial or radial radial of the limb. Based on these general principles, the defects can be categorized as follows: I. II. III. IV. V. VI. VII.
Failure of formation of parts (arrest of development). Failure of differentiation (separation) of parts. Duplication. Overgrowth (gigantism). Undergrowth (hypoplasia). Congenital constriction band syndrome. Generalized skeletal abnormalities.
This classification takes note of the similarities in certain large groups of deformities. Subclassification of these categories recognizes the basic differences and expresses the degree of severity of the type of deformity. As an example, the so-called radial "clubhand" is a failure of radial longitudinal formation; in addition to the fact that the radius is absent either partially or totally, the condition can be associated also with hypoplasia or aplasia of the thumb, carpal bones, or muscu-
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HAND SURGERY
UPPER LIMB (Ul) SHOULDER (Sh)
----II TOTAL
---1
ARM (Arm)
FOREARM (Fo)
lOWER LIMB (ll)
~PElVIS (Pel)
TOTAL UPPER 1/3 ~ MIDDLE 1/3 THIGH (Thigh) LOWER 1/3
t--1 ----1 TOTAL 1/3 UPPER MIDDLE 1/3 LOWER 1/3
LEG (Leg)
TOTAL PARTIAL
r-----TARSAL (Ta)
METACARPAL (Me)
TOTAL PARTIAL
r-----METATARSAL (Mt)
PHALANGEAL Ph
TOTAL PARTIAL
t-----PHALANGEAL (Ph)
CARPAL (Ca)
----1 ( )----1
Fig. 1. Failure of formation of parts, transverse . The digits are named by expressing the anatomical level at which the limb terminates. Attention is drawn to an oddity which apparently occurs: total absence of the shoulder or hemipelvis and all distal elements would be a transverse defect. However , if only a portion of the shoulder or hemipelvis were absent, the deficiency would be of the longitudinal type. lature on the preaxial or radial side of the limb. Each group can be subclassified into its degrees of severity, as desired for completeness. Experience with this classification has shown that it can function successfully in categorizing malformations. It has been used in a variety of clinics including efforts to program it for the computer. A very comprehensive clinical test was carried out by Flatt29 to determine its usability; it was his conclusion that the proposed classification was a properly conceived and practically usable classification for congenital anomalies of the limb. this classification was designed primarily for use with the hand anomalies. However, it also lends itself to use for the entire upper limb and for the lower limb as well. During 1974 the effectiveness of the new system of classification of congenital limb deficiencies was assessed by 15 specialized child-amputee centers in the United States and Europe which collectively classified some 400 congenital limb deficiencies. After resolving some relatively minor problems enc.ountered in this trial, the new system was endorsed for international use. It also was proposed to the World Health Organization for inclusion in the revision of the standard nomenclature.
Fig. 2. Category I: Failure of formation of parts, transverse. The cross-hatched area represents the area of embryological insult.
Failure of formation of parts. Rationale of categorization. The Subcommittee on Nomenclature and Classification of Congenital Limb Deficiency, * of the International Society for the Prosthetics and Orthotics , which met in Dundee in 1973 and Montreux in 1974, recommended an enlargement and refinement of Category I (failure of formation of parts) to define accurately the skeletal deficiencies seen in juvenile amputee clinics . 12, 14 Attention was given to the four basic categories proposed in the FrantzO'Rahilly3 work: terminal transverse or longitudinal and intercalary transverse or longitudinal. Unanimity of opinion was reached concerning the terminal transverse condition , that is, those presenting a congenital amputation-type stump. However, the existence of true intercalary deformities was questioned and, only after long discussion, agreement was reached that true intercalary deficiencies rarely, if ever, existed. It was postulated that all "phocomelias" or "intercalary deficiencies" in fact have some terminal manifestations, either a carpal or tarsal aberration, a defect of finger or *H. J. B. Day (England); H . L. Henkel (West Germany); Leon M. Kruger (U .S.A.); Douglas W. Lamb (Scotland); Ernest Marquardt (West Germany); Ross Mitchell (Scotland) ; Alfred B. Swanson (U .S.A.); H. G. Willert (West Germany); Hector Kay ( U.S.A.).
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Classification for congenital limb malformations
CD
CD
UPPER LIMB (U L)
SCAPULA (Sc) TOTAL OR PARTIAL
CLAVICLE (CI) TOTAL OR PARTIAL
ILIUM (Il) TOTAL OR PARTIAL
LOWER LIMB (LL) ISCHIUM (Is) TOTAL OR PARTIAL
PUBIS (Pu) TOTAL OR PARTIAL
FEMUR (Fern) TOTAL OR PARTIAL
HUMERUS (Hu) TOTAL OR PARTIAL RADIUS (Ra) TOTAL OR PARTIAL
ULNA (UI) TOTAL OR PARTIAL
TIBIA (Ti) TOTAL OR PARTIAL
FIBULA (Fib) TOTAL OR ·PARTIAL
METACARPALS (Me) TOTAL OR PARTIAL
2 3 4
RAYS
METATARSALS (Mt) TOTAL OR PARTIAL
2
3
4
RAYS
PHALANGES (Ph) TOTAL OR PARTIAL
RAYS
PHALANGES ) Ph) TOTAL OR PARTIAL
2
3
4
2
RAYS
3
11
4
Fig. 3. Failure of formation of parts, longitudinal. The names of all bones totally or partially absent are named. Any bone not named is presumed present. A, Upper limb. B. Lower limb
Fig. 4. Category I: Failure of formation of parts, longitudinal. A. Phocomelia represents the most profound expression of longitudinal failure of formation of parts. The cross-hatched area represents the maximal area of embryological insult. However, some defects of the terminal limb are also always present. B. Clinical example illustrating a complete phocomelia. Note the associated hand anomalies.
toe, or a deficiency of muscle, tendon, skin, or nail; this suggested that these so-called "intercalary" defects in reality are variable degrees of longitudinal deficiencies. It was decided that, except for the true transverse deficiencies (congenital amputation stumps), all others are a manifestation of some longitudinal aberration in the formation of parts; thus, even that condition described as "hypoplasia" of a limb or skeletal element, in reality, has a longitudinal failure in the sense
of the long axis of each bone. Similarly, although "phocomelia" presents a major manifestation of failure of formation in the long bones, there is also a lesser and perhaps minimal failure in the peripheral elements which, although present, are never truly normal. This concept of progressive longitudinal reduction can be carried to a point where only a single digital remnant of a limb remains and, ultimately, to the situation in which even this vestigial peripheral element failed to
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Fig. S. Category I: Failure of formation of parts, longitudinal-radial: radial ray deficiencies or radial deficiency (or the so-called "radial clubhand " or "radial hemimelia"). A, Diagram illustrating the areas of embryological insult. Band C, Clinical photograph and radiogram of a radial ray deficiency.
form-the true amelia. This, therefore , might be considered a maximum longitudinal deficiency, although presenting as a transverse-type defect. For simplicity of designation, however, amelia might best be categorized as a transverse deficiency. The category of failure of formation of parts is that group of congenital deficiences noted by failure or arrest of formation of the li mb either complete or partial . Based on the previous line of reasoning, it is divided into two types: transverse and longitudinal. The transverse defects would encompass all so-called congenital amputation-type conditions and include what heretofore were referred to as terminal transverse deficiences. The second major group, longitudinal deficiencies , then in effect would encompass all deficiencies which are not in the transverse category . This category is seen frequently in amputee centers because of the need for rehabilitation with prostheses. TRANSVERSE DEFICIENCIES. Transverse deficiencies present as amputation type stumps and are classified by naming the level at which the remaining limb terminates, it being understood that all elements distal to the level named also are absent (Fig. 1). The deficiencies in this group represent the so-called "congenital amputations" (a poor term, not to be confused with intrauterine amputations, which are not deficits of the limb), ranging from aphalangia to amelia. The stump usually is well padded with soft tissue and may show rudimentary digits or a dimpling at the end of the stump. It represents an arrest of formation in the limb anlage (Fig.
2). One of the most common types of transverse deficiency is at the level of the upper third of the forearm or "short below-elbow" defect. LONGITUDINAL DEFICIENCIES. All skeletal limb deficiencies in this category , other than the transverse type, are placed arbitrarily in the longitudinal group . In identifying longitudinal deficiencies, all completely or partially absent bones are named. Any bones not named as being absent are understood to be present (Fig. 3). The deficiencies in this group reflect the separation of the pre- and postaxial divisions in the limb and include longitudinal failure of formation of entire limb segments (phocomelias) or of either the radial, central, or ulnar components of the limb. The most profound expression of the longitudinal reduction of the limb is phocomelia , which demonstrates the proximal-distal failure of development. Phocomelia may be classified as: (1) complete phocomelia: the hand is attached directly to the trunk , demonstrating the failure of development of the proximal segments of the limb (Fig . 4); (2) proximal phocomelia: the proximal segment (arm) is mi ssing and the hand is attached to the forearm which is attached to the trunk; (3) distal phocomelia: the forearm is absent and the hand is attached directly to the arm. 3 The absence of parts or deficiencies on the radial (preaxial) side of the limb may vary from deficient thenar muscles to a short, floating thumb, and from deficient carpals, metacarpals, and radius to the classical so-called "clubhand" that we prefer to describe
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Classification for congenital limb malformations
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Fig. 6. Category I: Failure of formation of parts, longitudinal-central. A. Diagram illustrating the areas of embryological insult. Note the absence of the middle ray and associated failure of separation of parts between the little and ring fingers resulting in a cleft hand with syndactylysm of the little and ring fingers. B. Clinical example of a central deficiency or left hand.
as radial ray deficiencies or radial deficiency (Fig. 5). These deficits may involve the areas of the radius and thumb, radius only, or thumb only. In central ray or central (carpal and/or digital) deficiencies, the second, third, and fourth of the so-called "central" rays of the hand, which are noted to be embryologically differentiated at a separate time from the radial and ulnar rays, may be involved (Fig. 6). The middle finger or metacarpal may be missing as in the so-called "lobster-claw" hand. In severe central deficiencies, the central digits may be reduced to nubbins. In the severe case the defect may result in complete suppression similar to a transverse arrest resulting in aphalangia. In deficiencies of the ulnar side of the limb, the little or ring fingers may be deficient with or without associated deficiencies in the ulna and carpal bones (Fig. 7). These deficits may involve the areas of the ulna and fingers, ulna only, or fingers only. We describe these longitudinal arrests of formation of parts as ulnar ray deficiencies or ulnar deficiencies. Failure of differentiation (separation) of parts. Failure of differentiation or separation of parts is that category in which the basic units have developed but the final form is not completed. The homogenous anlage divides into separated tissues of skeletal, der-
Fig. 7. Category I: Failure of formation of parts, longitudinal-ulnar. Ulnar ray deficiencies or ulnar deficiency (or so-called "ulnar clubhand" or "ulnar hemimelia").
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Fig. 8. Category II: Failure of differentiation of parts . A. Synostosis. elbow and proximal radius and ulna . Band C. Syndactyly. D. Example of failure of differentiation of skin, muscle, ligaments, and capsular structures of the hand resulting in so-called arthrogrypoid hand.
Volume 1 Number 1 July, 1976
momyofascial, or neurovascular elements found in normal limbs, but fails to completely differentiate or separate. For example these defects may include the following: A. Shoulder 1. Undescended shoulder 2. Absence of pectoral muscle(s) B. Arm 1. Elbow synostosis C. Forearm 1. Soft tissues 2. Synostosis a. Proximal radius/ulna (Fig. 8, A) b. With/without radial head dislocation D. Hand 1. Carpal a. Deformities b. Synostosis 2. Metacarpal a. Deformities b. Synostosis 3. Digital a. Deformities b. Symphalangism c. Syndactyly (Fig. 8, B and C) 1. Simple 2. Complicated a. Soft tissue 1. Nails (synonychia) 2. Other b. Skeletal 1. Fusions a. Phalanges (side to side) b. Acrosyndactyly c. Apert's syndrome 2. Disarray 3. Brachysyndactyly (short webbed fingers) d. Contracture secondary to failure of differentiation of muscle, ligaments and capsular structures 1. Soft tissue a. Thumb web space b. Arthrogryposis (Fig. 8, D) c. Camptodactyly (flexion contracture of little finger) d. Trigger digit 2. Skeletal, a. Clinodactyly (lateral deviation or displacement due to asymmetrical abnormalities of the digits).
Classification for congenital limb malformations
15
Fig. 9. Category III: Duplications resulting from splitting of the original embryonic parts: A and B. phalanges, and C. socalled "mirror hand."
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Fig. 10. Category IV: Overgrowth (gigantism). A, Diagram showing involvement of the third and second digits. B, Example of involvement of the second digit.
Duplication. Duplications of parts probably occurs as a result of a particular insult to the limb bud and ectodermal cap at very early stages of their development so that splitting of the original embryonic part occurs (Fig. 9). These defects may range from polydactyly to twinning or mirror hands and can be classified as follows: A. Skeletal 1. Humerus 2. Radius 3. Ulna 4. Carpals 5. Metacarpals 6. Phalanges B. Skin and nails C. All tissues 1. Whole limb 2. Partial limb 3. Polydactyly a. Radial b. Central c. Ulnar 4. Mirror hand. Overgrowth (gigantism). The whole limb may be affected by overgrowth. Some cases appear to be due to skeletal overgrowth with normal-appearing soft parts. Others show excess fat; lymphangioma or angioma
Fig. 11. Category V: Undergrowth (hypoplasia). This can be a local or more generalized involvement. Diagram illustrates the involvement of the entire hand.
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Classification for congenital limb malformations
17
Fig. 12. Category VI: Congenital constriction hand syndrome. A, At the middle of the arm . B, At the hand resulting in pseudosyndactylysm . Most frequently the web spaces are intact and the fused mass of digital substance is the result of intrauterine healing of the necrotic areas involving the digits. This must not be confused with true syndactylysm resulting from failure of differentiation of parts .
Fig; 13. Category VII: Generalized skeletal defects illustrated by (A) achondroplastic extremity and (B) typical hand of diastrophic dwarf.
may be present. In digital gigantism the abnormality usually is greatest at the periphery. Deformities may increase secondarily due to asymmetrical growth of the part (Fig. 10). Gigantism may involve the following: (I) arm; (2) forearm; (3) hand; (4) digit. Undergrowth (hypoplasia). Undergrowth, or hypo-
plasia, denotes defective or incomplete development of the parts. This may be manifested in the entire extremity or its divisions (Fig. II) . Hypoplasia may be used as a supplemental description for remaining skeletal elements in cases of failure of formation of parts (Category I). However, this category should be represented
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separately in this classification system because of the prevalence of this condition. Hypoplasia may involve any of the following systems: A. Skin and nails B. Musculotendinous C. Neurovascular D. Extremity I. Arm 2. Forearm 3. Hand a. Whole hand b. Metacarpals (brachymetacarpia) c. Phalanges (brachyphalangia). Congenital constriction band syndrome. Focal necrosis along the course of the limb may happen in the postembryonic stage of development. The annular constriction bands or rings are a result of an area of necrosis involving the superficial tissues which heals as a circular scar (Fig. 12, A). When these constriction bands are severe, they may result in intrauterine gangrene and true fetal amputations may occur. The occasional associated syndactyly in these cases may be the end result of the intrauterine healing process (Fig. 12, B). The necrosis of tissue and its resultant fusion of parts is not unlike an untreated third degree burn with bridges of scar. The syndactyly and confused anatomical arrangements of parts found in these patients may be the result of a healing necrotic infarct occurring during the stage of separation of parts. Controversy has existed as to whether this is an intrinsic or extrinsic defect. Amniotic bands have been implicated as the cause of these defects; others feel that the amniotic bands are secondary to the healing limb injury. Generalized skeletal abnormalities. Defects in the hand may be a manifestation of a generalized skeletal defect, such as appears in dyschondroplasia, achondroplasia, Marfan's syndrome (with arachnodactyly), diastrophic dwarfism, etc. (Fig. 13).
How to use the classification Each patient reviewed should be recorded on a silhouette drawing which shows an outline of the limb and of the skeletal parts such as shown in Figs. 14 and 15. Shading out of absent parts and labeling of associated defects can facilitate the subclassification of deficits. Further description of deficient parts can be facilitated by anatomical divisions of the limb into shoulder girdle, arm, forearm, and hand. These can be broken down further into carpus, digits (I, 2, 3,4, 5), phalanges (1, 2, 3), proximal, middle, and distal parts of long bones. Description of muscle loss, skin and nail variations, nerve, motor, or sensory deficits, associated
HAND SURGERY
contractures or relaxations, and such conditions as the subluxation or dislocation of joints, range of motion of joints, vascular anomalies associated with spinal, visceral, or other soft tissue defects can be listed for completeness. Occasionally the insult to the limb may result in apparent mixed involvement. As an example, the failure of formation may be manifested as an almost transverse arrest of the entire hand with only rudimentary radial and ulnar digits present (Fig. 16). Where there is variable involvement of the rays of the hand, the judgment of the clinician will be required to categorize these relatively rare cases appropriately. He should place the particular patient into the category which represents the predominant deficiency. The need for this type of categorization does not arise very frequently, in our experience. It was decided to eliminate Greek and Latin terms, such as "peromelia," "ectromelia," "hemimelia," and" meromelia," and to attempt to describe deficiencies in the simplest yet most precise language which would be understandable by all the English-speaking world and be easily translatable into other languages. However, there should be no objections to retaining some existing terms in common use in the subclassification of these conditions. Cases of transverse arrest of the limb may be categorized easily by using the conventional amputation levels. As an example, a certain type of congenital transverse arrest of development of the forearm might also be described as a "transverse arrest, short below-elbow type."
General rules in the use of the classification of congenital limb deficiencies. Abbreviations. In anatomical description and classification the use of abbreviations and acronyms frequently provides a system of shorthand which is of value as long as the meanings of the terms employed are essentially self-evident. Abbreviation terms for the anatomical components are suggested in Fig. 3. When one or more metacarpals or metatarsals and the corresponding phalanges are completely absent, simply refer to them as rays. Terms such as "transverse" and "longitudinal" can be abbreviated with little danger of confusion. For example: TIL and T/R for transverse left and right, respectively; and L/L and L/R for longitudinal left and right. Similarly when two sequent bones are affected to the same degree, they could be combined in the classification. Thus a combined longitudinal deficiency of the right upper limb, humerus total, radius total, carpus partial, metacarpal I, 2 total, phalanges, I, 2 total, could more simply be written L/R, Hu and Ra total, Ca partial, Rays I, 2 total.
Volume I Number I July, 1976
Classification for congenital limb malformations
Supplemental conditions. Always put absences first followed by supplemental conditions, e.g., T/R, Ca partial; with hypoplasia of Ra and U 1 . In hypoplasia associated with transverse deficiencies as above, name hypoplastic leg or forearm bones, since one may be affected but not the other. In partial absence of long bones in longitudinal deficiencies, identify the approximate amount of missing segment, e.g., L/L, Hu partial (prox. 3/4). Order of classification. In classifying longitudinal deficiencies always proceed from proximal to distal,
e.g., L/R, Hu partial (prox. 3/4); VI total; Ca partial. Surgery. Although the surgical conversion of congenital deficiencies is not a basic classification item, information on such conversion may be included on the description-classification form as supplemental data as follows. (1) In cases of surgical amputation to provide a better limb remnant for prosthetics fitting,. e.g., a Syme's type amputation in the case of a complete absence of the fibula, a horizontal line (-) in red pencil or ink should be made on the form at the appropriate level. (2) In cases of reconstructive surgery, e.g., in the
DESCRIPTION - CLASSIFICATION FORM/CONGENITAL SKELETAL LIMB DEFICIENCIES - UPPER LIMB CLINIC Grand Rapids NAME.""N""or",m;!-a*:B",'"-----""""H""''''''''''',,.-- SEX~ CASE NO. _ _ _DATE~ RACE CaucasjanBIRTH DATE~X-RAYS DATE~LACE OF BIRTH '"'('""c"",t""y'}----r::(c::::ou:::nT.t,..y'=-}-=--=--=--=--=--=-("'s_t'::.at~e,...}KEY 1. SCAPULA
2·. 3. 4, 5. 6. 7. 8. 9. 10 .
CLAVICLE SHOULDER JOINT f - - - - - HUMERUS ELBOW JOINT ULNA RADIUS WRIST JOINT CARPALS METACARPALS 11. PHALANGES
- - - - - - - 1 Hemivertebrae D-4. u-6;
10 ribs left
9
_ _ _ _ _ _ _ 10
Carpal bones not cgmpletely ossifiE.d 10
_ _ _ _ _ _ _ 11
FUNCTIONAL AMPUTATION LEVEL CLASSIFICATION .RIGHT : L/·"'Rc-.""R-a-pa-r7' tiC-a '-l;-'CC'-a-p-a-:rt-:-ia""'I-'Me ray 1; Ph ray 1.
19
CLASSIFICATION, LEFT
: L/l Ra complete' Ca partjal' fic ray 1 ~ Ph ray 1.
Fig. 14. Limb silhouette (A) and clinical photograph (B) illustrating a case of radial ray deficiency (or socalled "radial-clubhand" or "radial hemimelia" in the old classification). This defect is in Category I of the classification: longitudinal failure of formation of parts .
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The Journal of
Swanson
HAND SURGERY
DESCRIPTION - CLASSIFICATION FORM/CONGENITAL SKELETAL LIMB DEFICIENCIES - LOWER LIMB
_==____===_ _ -,==__
CLINIC Grand Rapids NAME vN",a;.;:nC~y~Fi·
8. 9. 10.
11.
12.
SACRUM INNOMINATE HIP JOINT FEMUR PATELLA KNEE JOINT TIBIA FIBULA ANKLE JOINT TARSALS METATARSALS PHALANGES
SublllXed
1--------1 2________
~
DATE ~ (state)
ANCt-iALl ES OTHER THAN OF LIMBS
ta ) liS
_ __ _ _ _ 10
10 - - - - - - - - - -
-----------~1
11--------
FUNCTIONAL AMPUTATlDN LEVEL _~L~ tYre
FUNCTI ONAL AMPUTATION lEVEL
Cl'SSIFIC'.TI0N, RIGHT: L/R Fib total; Mt 5 total ;Ph 5 total
1 2 - - -- -- -_ _
CLASSIFICATION, LEFT:
Fig. 15. The lower extremity can be affected by the same range of defects as the upper extremity. Limb silhouette (A) and clinical photograph (B) illustrating a case of fibular ray deficiency (or so-called "fibular hemimelia"
in the old classification) . This is in Category I of the classification: longitudinal failure of formation of parts.
Volume 1 Number 1 July, 1976
Classification for congenital limb malformations
21
It is vitally important that a uniform classification be adapted throughout the world in order to facilitate the monitoring of the congenital malformations, to permit comparisons of incidence between the different areas, and to assist in the research regarding possible etiological factors, prevention, and selection of most efficacious methods of management. These are mandatory for the establishment of national registries for collection of baseline data and for establishment and coordination studies carried on by individuals and institutions. The author wishes to thank Dr. Genevieve Swanson, Shirley Furgerson, and Richard Scherzer for their assistance in the preparation of this paper.
REFERENCES I. Boyes, J. H.: Bunnell's surgery of the hand, ed. 5, Phila-
Fig. 16. Occasionally the insult to the limb may result in apparent mixed involvement. As an example, the failure of formation of parts may be manifested as an almost transverse arrest of the hand with only rudimentary digits present.
pollicization of the index finger in certain cases of radial ray deficiency, the operation should be indicated by an (X), again in red pencil or ink, at the area involved. (3) An osteotomy would be shown by an appropriate marking in red pencil or ink. A problem common to all classification systems is that radiograms taken when a child is very young may not reveal bones which are not ossified yet; thus early diagnosis should be considered tentative and subject to revision when the child is followed with radiograms at a more mature age. Another problem encountered is that some bone remnants are unidentifiable. It is recommended that the classifier use his best judgment as to what is present or missing but indicate by a (?) that this is a presumption and not necessarily an exact identification.
Comment The Classification of Congenital Malformations presented has received international approval and should facilitate the coding of these patients. We urge every clinic and institution concerned with the management of congenital malformations of the upper extremity to test the validity and practicality of this classification. This is an important undertaking and it requires the utmost international cooperation.
delphia, 1970, J. B. Lippincott Company. 2. Kelikian, H.: Congenital deformities of the hand and forearm, Philadelphia, 1974, W. B. Saunders Company. 3. Frantz, C. H., and O'Rahilly, R.: Congenital skeletal limb deficiencies, 1. Bone Joint Surg. 43A: 1202, 1961. 4. Barsky, A. J.: Congenital anomalies of the hand and their surgical treatment, Springfield, Ill., 1958, Charles C Thomas, Publisher. 5. Patterson, T. J. S.: Congenital deformities of the hand. Hunterian Lecture delivered at Royal College of Surgeons of England, April, 1959. 6. Entin, M. A.: Reconstruction of congenital abnormalities of the upper extremities, J. Bone Joint Surg. 41A: 681, 1959. 7. Entin, M. A., Barsky, A. J., and Swanson, A. B.: Committee report to American Society for Surgery of the Hand, 1966. 8. Hall, C. B., Brooks, M. B., and Dennis, J. F.: Congenital skeletal deficiencies of the extremities: Classification and fundamentals of treatment, J. A. M. A. 180: 590, 1962. 9. Aitken, G. T.: Proximal femoral focal deficiencydefinition, classification, and management, in Proximal femoral focal deficiency-a congenital anomaly, NAS Publication 1734, 1969, pp. 1-22. 10. Burtch, R. L.: Nomenclature for congenital skeletal limb deficiencies, a revision of the Frantz and O'Rahilly classification, Artif. Limbs. 10: 24, 1966. 11. Henkel, H. L., and Willert, H. G.: Dysmelia, a classification and a pattern of malformation of congenital limb deficiencies, J. Bone Joint Surg. SIB: 399, 1969. 12. International Society for Prosthetics and Orthotics, Working Group: The proposed international terminology for classification of congenital limb deficiencies, London, 1975, Spastics International Medical Publications in association with W. Heinemann Medical Books, Ltd., and 1. B. Lippincott Company. 13. Kanavel, A. B.: Malformations of the hand, Arch. Surg. 24: 153 and 282,1932.
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The Journal of HAND SURGERY
Swanson
14. Kay, H. W.: A proposed international terminology for the classification of congenital limb deficiencies, Orthop. Pros. J. 28: 33-48, 1974. 15. Kelikian, H., and Doumanian, A.: Congenital anomalies of the hand, J. Bone Joint Surg. 29A: 1002 and 1249, 1957. 16. O'Rahilly, R.: Morphological patterns in limb deficiencies and duplications, Am. J. Anat. 89: 135, 1951. 17. Saunders, J.: Inductive interplay during limb development. Lecture delivered before Annual Meeting of Juvenile Amputee Clinic Chiefs (Subcommittee on Child Prosthetics Problems NAS-NRC), Chicago, Jan. 1966. 18. Swanson, A. B.: Unusual anomalies in the upper extremity, Orthop. Pros. J. 14: 47, 1960. 19. Swanson, A. B.: A classification for congenital malformations of the hand, N. J. Bull. Acad. Med. 10: 166, 1964. 20. Swanson, A. B.: Phocomelia and congenital limb malformations. Surgical reconstruction and prostehtic replacement, Kobe J. Med. Sci. 2 (Suppl.): Dec., 1965. 22. Swanson, A. B.: Classification of limb malformations on the basis of embryological failures: A preliminary report, N. Y. Univ. Inter.-C1in. Info. Bull. 6: I, 1966. 23. Swanson, A. B.: Severe congenital anomalies of the upper limb, considerations for classifications and treatment in Cramer, L. M., and Chase, R. A., editors: Symposium on the hand, Vol. 5, St. Louis, 1971, The C. V. Mosby Company, pp. 132-149. 24. Swanson, A. B., Barsky, A. J., and Entin, M. A.: Classification of limb malformations on the basis of embryological failures, Surg. C1in. North Am. 48: 1169, 1968. 25. Swanson, A. B., and Fujiwara, A.: Review of 300 cases of congenital malformation. Unpublished data from Michigan Area Amputee Clinc, 1963.
26. Duraiswami, P. K.: Experimental causation of congenital skeletal defects and its significance in orthopaedic surgery, J. Bone Joint Surg. 34-A: 646, 1952. 27. Bagg, H. J.: Etiology of certain congenital structural defects, Am. J. Obstet. Gynecol. 8: 131, 1924. 28. Birch-Jensen, A.: Congenital deformities of the upper extremities, Copenhagen, 1950, Ejnar Munksgaards, Forlag. . 29. Flatt, A. E.: A test of a classification of congenital anomalies of the upper extremity, Surg. C1in. North Am. 50: 509, 1970. 30. Frantz, C. H.: Increased incidence of malformed infants in West Germany during 1959-62, III. Med. J. 123: 27, 1963. 31. Hepp, 0.: Frequency of the congenital defectanomalies of the extremities in the Federal Republic of Germany, N. Y. Univ. Inter. C1in. Inform. Bull. 1: 3, 1962. 32. Jentschura, G., Marquardt, E., and Rudel, E. M.: Malformation and amputations of the upper extremity: Treatment and prosthetic replacement, New York, 1967, Grune & Stratton, Inc. 33. Taussig, H. B.: A study of the German outbreak of phocomelia, J. A. M. A. 180: 1106, 1962. 34. Warkany, J., and Schraffenberger, E.: Congenital malformations induced in rats by roentgen rays, Am. J. Roentgenol. Radium Ther. Nucl. Med. 57: 455, 1947. 35. Willert, H. G., and Henkel, H. L.: Klinik und pathologie der dysmelie: die fehlbildungen an den oberen extremitaten bei der thalidomid-embryopathie, Heidelberg, New York, 1969, Springer-Verlag.
From Kidd, John: On the adaptation of external nature to the physical condition of man, London, 1852, H. G. Bohn, p. 27. Quoting from Galen, The use of various parts of the body: Nor have we yet enumerated the most important of those priveleges which the hand imparts to man. With this he weaves the garment that protects him from the summers heat or winters cold; with this he forms the various furniture of nets and snares, which give him dominion over the inhabitants as well of the water as of the air and earth; with his hand he constructs the lyre and lute and the numerous instruments employed in the several arts of life; with the hand he erects altars and shrines to the immortal gods; and lastly by means of the same instrument, he bequeaths to posterity, in writing, the intellectual treasures of his own divine imagination; and hence we, who are living at this day, are enabled to hold converse with Plato, and Aristotle, and all the venerable sages of antiquity.