Radial Clubhand 

Updated: Apr 20, 2018
Author: Scott H Kozin, MD; Chief Editor: Harris Gellman, MD 

Overview

Background

Radial clubhand is a deficiency along the preaxial or radial side of the extremity. Although considerable forearm and hand anomalies are the classic findings, proximal deficiencies also can occur throughout the arm and shoulder girdle. The elbow abnormalities can include deficiences of the olecranon, capitellum, coronoid fossa, and medial epicondyle.

In 1733, Petit first described radial clubhand in an autopsy of a neonate with bilateral clubhands and absent radii. Subsequent autopsy observations detailed the anomalous anatomy associated with radial clubhand and the associated malformations of other body systems.

Initial surgical treatment of radial clubhand involved an ulnar osteotomy to correct the bow, along with splitting of the distal ulna for insertion of the carpus. Reconstruction of the radius with a bone graft to support the carpus was reported in the 1920s, and nonvascularized epiphyseal transfer was reported in 1945. Results of these procedures were disappointing. They had multiple causes of failure, including disruption of the ulnar growth plate and subsequent increase in limb-length discrepancy, inadvertent ankylosis or arthrodesis of the wrist and loss of motion, and failure of the transplanted bone to grow, with eventual loss of radial support.

Centralization of the carpus on the distal ulna has emerged as the preferred surgical technique for correcting radial clubhand.[1, 2] Pioneers in congenital hand surgery developed the basis for this procedure. Numerous modifications have been described to obtain or maintain correction of the wrist on the ulna.

Radialization is a technique that involves overcorrection of the carpus on the ulna combined with tendon transfer to further rebalance the wrist.[3]

Despite over 250 years of investigation, current treatment regimens are still unable to restore normality: The limb remains short, and the wrist lacks full function.

This article summarizes the history of radial deficiencies, lists potential etiologies, highlights relevant pathoanatomy, discusses treatment regimens, reviews expected outcome, and details potential complications.

Anatomy

Bone and joint abnormalities

Clinical features of radial deficiency (types II, III, and IV; see Presentation, Classification) are dramatic, with abnormalities of the entire extremity. The scapula is often small, and the clavicle is often shorter, with an increased curvature. The humerus may or may not be short, and deficiencies of the capitellum and trochlea are common. Elbow motion is usually diminished more in flexion than in extension.

The forearm is always decreased in length, and the ulna is approximately 60% of the normal length at the time of birth. This discrepancy persists throughout the growth period and into adulthood. True forearm rotation is absent in patients with partial or complete aplasia of the radius.

The wrist is radially deviated and develops a perpendicular relation to the forearm over time. The articulation between the carpus and ulna is usually fibrous and abnormal, though some hyaline cartilage can be found. Wrist motion is primarily in the radial/ulnar plane, with some flexion/extension. Ossification of the carpal bones is delayed, with the scaphoid and trapezium often absent or hypoplastic. The capitate, hamate, and triquetrum are usually present but ossify late.

The fingers are often stiff, with limited motion at the metacarpophalangeal (MCP) and interphalangeal (IP) joints. The preaxial index and long fingers are more affected than the postaxial ring and small digits.

Muscle and tendon abnormalities

Numerous muscular abnormalities are found throughout the upper extremity. The deltoid or the pectoralis major can be hypoplastic, can be partially absent, or can have an abnormal insertion. The biceps may be absent or fused to the underlying brachialis.

The forearm demonstrates the most severe abnormalities, which may involve any of the muscles that originate from or attach to the radius, including the following:

  • Extensor carpi radialis longus
  • Extensor carpi radialis brevis
  • Pronator teres
  • Flexor carpi radialis
  • Palmaris longus
  • Flexor pollicis longus
  • Pronator quadratus
  • Supinator

The extrinsic flexors and extensors of the fingers are usually adherent, with abnormal origins and insertions. The flexor and extensor carpi ulnaris, as well as the interossei, lumbricals, and hypothenar muscles, are often normal, whereas abnormalities of the thumb muscles are more related to the degree of thumb hypoplasia.

Nerve and artery abnormalities

The radial nerve usually terminates at the elbow, and the ulnar nerve is normal. An enlarged median nerve substitutes for the absence of the radial nerve and supplies a dorsal branch for dorsoradial sensibility. This subcutaneous branch is positioned in the fold between the wrist and forearm and must be protected during surgery. The vascular anatomy demonstrates a normal brachial and ulnar artery. The radial artery is often absent, and the interosseous arteries usually remain patent.

Associated abnormalities

Radial deficiency is associated with numerous systemic conditions,[4] including Holt-Oram syndrome (cardiac septal defects); TAR syndrome; Fanconi anemia (aplastic anemia); and VACTERL syndrome.[5, 6] In addition to these conditions, a variety of associated musculoskeletal deformities appear sporadically. These include cleft palate, clubfoot, kyphosis, scoliosis, torticollis, and rib deformities.

Pathophysiology

The forearm is foreshortened, and the wrist is positioned in radial deviation. This malalignment assumes a perpendicular relation over time (see the image below).

Perpendicular relationship between wrist and forea Perpendicular relationship between wrist and forearm in radial clubhand.

The right-angle position (see the image below) further shortens the limb and limits the ability to reach into space. The awkward angulation between the wrist and forearm places the extrinsic flexors and extensors at a mechanical disadvantage. The tendons must traverse this angle to elicit finger motion, and this limits the ability to move the digits.

Right angle between wrist and forearm. Right angle between wrist and forearm.

Etiology

In the 19th century, the etiology of radial clubhand was theorized to be either a congenital absence or an acquired defect secondary to syphilis. In 1895, Kummel proposed the cause to be abnormal pressure upon the embryo along the radial bud between the third and seventh week of gestation.

Current theory relates the etiology of radial clubhand to the apical ectodermal ridge (AER). This structure is a thickened layer of ectoderm that directs differentiation of the underlying mesenchymal tissue and limb formation. Removal of a portion of the AER in chick embryos has produced anomalies similar to radial clubhand.[7] Therefore, a defect of the AER is the most probable cause of radial clubhand, with the extent of deformity related to the degree and extent of the AER absence.[8]

Epidemiology

The reported incidence of radial clubhand ranges from 1 in 55,000 to 1 in 100,000 live births. Most cases are sporadic without any definable cause. However, exposure to teratogens, such as thalidomide and radiation, can yield radial deficiencies.

Radial deficiency is bilateral in 50% of cases and is slightly more common in males than in females (3:2). The incidence of radial deficiency within the same family is low, ranging from approximately 5% to 10% of reported cases; it is most common in radial aplasia associated with cardiac abnormalities.

Prognosis

Comparison of results following centralization is difficult because of the many surgical modifications, variations in technique to determine the degree of deformity, and potential inconsistencies in measurement. Measurements to determine the deformity have been discussed by numerous authors.[9, 10]

Heikel described the construction of lines to calculate ulna curvature and overall deformity.[11]  He also discussed the difficulties with measurements of angles in radial clubhand, including inexact determination of lines and the difficulties in obtaining a standardized radiographic view of the radial clubhand.

Manske et al, as well as Bayne and Klug, recommended the hand-forearm angle using the longitudinal axis of the third metacarpal and distal ulna, whereas Bora et al used the ulnar bow to assess deformity and recurrence.[12, 13, 14, 15]  Damore et al used total angulation, which is the combination of radial deviation of the hand and the ulna bow.[16]  This represents the clinical deformity by combining the radial deviation of the wrist and ulna bow.

Lamb monitored 31 centralizations for an average of 5 years and measured a preoperative radial deviation of 78° and a follow-up angle of 22°.[17]  Bora et al reported on 14 extremities at an average of 14.6 years after centralization and showed a gradual increase in the hand-forearm angle to an average of 25°.[15]  Manske et al reported on 21 radial clubhands and measured the hand-forearm angle at 58° preoperatively and 26° at an average 34-month postoperative period.[12]

Watson et al monitored 12 centralizations for 10 years and reported a recurrence to an average of 30°.[18]  Bayne and Klug monitored 53 patients for an average of 8.6 years and reported 81% good or satisfactory results, defined as a hand-forearm angle of less than 30°.[13]  Damore et al monitored 14 patients for an average of 7 years.[16]  An initial significant improvement from a preoperative total angulation of 83° to an immediate postoperative angle of 25° was noted. At follow-up, total angulation had increased to 63°, with a 38° loss of correction.

Kotwal et al, in a retrospective analysis of 446 patients with type III and IV radial longitudinal deficiency treated over a 20-year period, found that patients treated with surgery had better appearance, function and performed better with activities when compared to those treated with stretching and splinting alone.[19]

In Vilkki’s long-term follow-up of 19 wrists followed for over 11 years treated with vascularized second metatarsophalangeal transfer, average final hand-forearm angle was 28º of radial deviation.[20]  Total active wrist motion averaged 83º (range, 30-115º). Overall ulnar growth averaged 15.4 cm, and overall relative ulnar length was 67% of the contralateral side (range, 51-78%).

 

Presentation

History and Physical Examination

Clinical presentation of radial clubhand varies with the degree of radial deficiency (see Classification) and the presence of associated anomalies. Radial deficiency is the classic anomaly that is associated with systemic conditions.[5]  All forms, regardless of the degree of expression, warrant systemic evaluation. The prominent syndromes are as follows:

  • Holt-Oram syndrome
  • TAR (thrombocytopenia-absent radius) syndrome
  • VACTERL (vertebral, anal, cardiac, tracheal, esophageal, renal, and limb) syndrome
  • CHARGE ( coloboma of the eye, heart defects,  atresia of the nasal  choanae, retardation of growth or development,  genital or urinary abnormalities, and ear abnormalities and deafness) syndrome
  • Fanconi anemia [21]

The principal organ systems involved in these are the cardiac, renal, and hematology cell lines (see Table 1 below). Children with VACTERL syndrome can also have vertebral, tracheoesophageal, and anal problems. Isolated radial deficiency is estimated to account for only 8-30% of the cases.[22]

Table 1: Syndromes or Associations With Radial Deficiency (Open Table in a new window)

Syndrome or Association

Characteristics

Holt-Oram

Heart defects, most commonly cardiac septal defects

Thrombocytopenia-absent radius (TAR) syndrome

Thrombocytopenia present at birth (may require transfusions), but improves over time

VACTERL association

Vertebral abnormalities, anal atresia, cardiac abnormalities, tracheoesophageal fistula, esophageal atresia, renal defects, radial dysplasia, lower-limb abnormalities

Fanconi anemia

Aplastic anemia not present at birth, develops about 6 years of life

CHARGE syndrome

Coloboma of the eye, heart defects, atresia of the nasal choanae, retardation of growth or development, genital or urinary abnormalities, and ear abnormalities and deafness

Limb evaluation often occurs prior to the diagnosis of Fanconi anemia. The diagnosis can be confirmed with the chromosomal breakage test. The precise indication for a chromosomal breakage test for this condition in children with limb anomalies is still evolving. Testing every child with isolated thumb or hand abnormalities should be consid­ered. I recommend a chromosomal breakage test on all children with deficiencies of the thumb and radial border of the forearm. Additional findings, such as abnormal skin pigmentation (café-au-lait spots), kidney abnormalities, growth retardation, and microcephaly, add to the suspicion of Fanconi anemia.

Careful clinical examination is used to assess the degree of involvement. The shoulder, elbow, wrist, and digital range of movement are evaluated for active and passive motion. This establishes a baseline for assessing treatment outcome. The ability to flex the elbow for hand-to-mouth function is examined; this influences the treatment algorithm. The position of the wrist with respect to the ulna and the ability to passively correct the radial deviation also are measured.

The thumb is examined for hypoplasia and graded accordingly.[23]  Thumb deficiency contributes to functional impairment. Stiffness of the fingers is assessed, and the ability to grasp and release is determined via functional tasks. Compensatory movements are noted to prevent inadvertent disruption of these adaptive mannerisms with surgical intervention.

Classification

Radial clubhand is classified into the following four types according to the amount of radius present:

  • Type I deficiency - The mildest type, this is characterized by mild radial shortening of the radius without considerable bowing; minor radial deviation of the hand is apparent, though considerable thumb hypoplasia may be evident
  • Type II deficiency - This is characterized by a miniature radius with distal and proximal physeal abnormalities and moderate deviation of the wrist
  • Type III deficiency - This is characterized by a partial absence of the radius (most commonly the distal portion) and severe wrist radial deviation
  • Type IV deficiency - The most common variant (see the image below), this is characterized by a complete absence of the radius; the hand tends to develop a perpendicular relation to the forearm
Radiograph of type IV deficiency with complete abs Radiograph of type IV deficiency with complete absence of radius.

A modified classification of radial longitudinal deficiency has been developed to combine thumb, carpal anomalies, and forearm into a single scheme (see Table 2 below).[24]  This scheme grades both thumb and radius deficiencies on the basis of radiographic findings. The delayed ossification of the radius and carpus in preaxial deficiency must be considered during application of this scheme. Radial-side carpal bones appear even later than the ulna, which delays definitive determination of carpal anomalies.

Table 2: Global Classification of Radial Longitudinal Deficiency (Open Table in a new window)

Type

Thumb Anomaly

Carpal Anomaly*

Distal Radius

Proximal Radius

N

Absence or hypoplasia

Normal

Normal

Normal

O

Absence or hypoplasia

Absence, hypoplasia, or coalition

Normal

Normal, radioulnar synostosis, or radial head dislocation

1

Absence or hypoplasia

Absence, hypoplasia, or coalition

>2 mm shorter than ulna

Normal, radioulnar synostosis, or radial head dislocation

2

Absence or hypoplasia

Absence, hypoplasia, or coalition

Hypoplasia

Hypoplasia

3

Absence or hypoplasia

Absence, hypoplasia, or coalition

Physis absent

Variable hypoplasia

4

Absence or hypoplasia

Absence, hypoplasia, or coalition

Absence

Absence

*Carpal anomaly implies hypoplasia, coalition, absence or bipartite carpal bones. Hypoplasia and absence are more common on the radial side of the carpus, and coalitions are more frequent on the ulnar side.

Radiographs must be taken after the age of 8 years to allow for ossification of the carpal bones.

 

Workup

Laboratory Studies

The appropriate workup for associated conditions necessitates referral to pediatric subspecialists.[5] The heart is evaluated by means of auscultation and echocardiography. The kidneys are examined by means of ultrasonography, and the platelet status is assessed by means of blood count and peripheral blood smear.

The most devastating associated condition is Fanconi anemia. Children with Fanconi anemia do not have signs of bone marrow failure at birth; therefore, the diagnosis is not initially apparent. The majority of children experience signs of aplastic anemia between the ages of 3 and 12 years (median age, 7 years). However, a chromosomal challenge test is available that allows detection of the disease before the onset of bone marrow failure. This assay subjects a sample of the child’s lymphocytes to diepoxybutane or mitomycin C, which cause chromosomes within Fanconi anemia cells to break and rearrange. In contrast, lymphocytes in unaffected children are stable to these agents.

Because bone marrow transplant is the only cure for Fanconi anemia, this prefatory diagnosis is crucial for the child and family. Early diagnosis provides ample time to search for a suitable bone marrow donor or consider preimplantation genetic diagnosis (PGD). PGD is a sophisticated technique that involves in-vitro fertilization, sampling of the blastocytes to ensure human leukocyte antigen (HLA) similarity without Fanconi disease, and reimplantation until birth. At delivery, cord blood is harvested from the newborn and used as a source of stem cell transplant to the affected sibling.

Since PGD takes time, early detection via a chromosomal challenge test is critical and may ultimately save the affected child. The pancytopenia can be treated with bone marrow transplantation, but even with these efforts, life expectancy is only estimated at 30 years (range, 0-50 years).

Imaging Studies

Plain radiographs are obtained to evaluate the degree of radial aplasia and to assess associated abnormalities of the elbow, wrist, and hand (see the image below).

Radiograph of type IV deficiency with complete abs Radiograph of type IV deficiency with complete absence of radius.

In radial clubhand, ossification is delayed, and final determination of complete aplasia of the radius or carpus must be deferred until later (up to the age of 8 years).

 

Treatment

Approach Considerations

The objective of treatment in radial clubhand is to reduce the functional deficit incurred by a short or absent radius, a short ulna, an abnormal muscular anatomy, and a radial deviation of the wrist. Type I radial clubhands have minor radial deviation of the wrist, which creates less of a functional problem than types II, III, and IV (see Presentation, Classification). In those children with considerable absence of the radius, the wrist assumes severe radial deviation that increases to 90° over time. This further compromises the flexor and extensor tendons, creating functional difficulty.

Thumb hypoplasia also requires consideration in the formulation of a treatment plan for radial clubhand. An absent or deficient thumb inhibits use of the hand. Reconstruction or pollicization is necessary to optimize hand function.[25]  Thumb reconstruction is usually delayed until after forearm treatment. Centralization is indicated in radial clubhand types II, III, and IV, in which there is severe radial wrist deviation and insufficient support of the carpus.

Contraindications for surgical intervention are mild (type I) deformity in children and elbow extension contractures that prevent the hand from reaching the mouth if the deformity at the wrist is corrected. Surgery is also contraindicated for adults who have adjusted to their deformity.

Numerous modifications and advances have been made in the technique of centralization. Improved methods have been developed to balance the wrist with additional tendon transfers or overcorrection of the wrist into ulnar deviation (ie, radialization). Better attempts at stretching the soft tissue with distraction techniques and bone-lengthening procedures also are used today.[26, 27, 28] In addition, microsurgical transfer of a viable growth plate (fibula, second toe) to the radial side of the forearm provides a support of the radial carpus that continues to grow over time.

A successful centralization still results in a shortened forearm segment secondary to altered growth of the ulna. The short forearm is both a cosmetic and a functional problem for the teenager with radial deficiency. Lengthening of the ulna can be accomplished by using distraction osteogenesis. Uniplanar and multiplanar devices have been employed depending on the deformity, forearm size, and surgeon preference.

Successful lengthening results in functional improvement because an increased volume of space becomes available for the hand, though complications are common.[29]  Restoration of near-equal forearm length promotes use of the extremity during activities of daily living.[30]  However, serious complications can occur with lengthening procedures in children with radial deficiencies.[31] The appropriate indications and age for surgery and amount of length obtainable remain profound questions.

These procedural changes represent new concepts to correct radial clubhand. These technologic advances in limb lengthening and microsurgery add innovative methods to better correct the deformity and provide osseous support. Follow-up results of vascularized second metatarsophalangeal joint transfer to stabilize the carpus are encouraging with respect to motion and less recurrence.

Medical Therapy

Medical treatment is directed at any of the aforementioned associated syndromes. Appropriate treatment for these conditions requires referral to pediatric subspecialists.

Correction of radial clubhand requires a combination of nonoperative and operative management that begins shortly after birth. Instruction in passive stretching of the taut radial structures is provided at the initial visit. This stretching is performed at each diaper change and at bedtime. A stiff elbow with limited motion also is stretched during this time. Splint fabrication is difficult in the newborn, especially with a shortened forearm. Therefore, splint use is delayed until the forearm is long enough to accommodate a splint. Serial casting can also be used to gradually stretch the tight radial structures.

Surgical Therapy

Centralization of the wrist on the ulna is the standard treatment to correct radial deviation. This procedure is performed in patients aged approximately 1 year. Surgery at this time allows improvement in forearm length and provides a foundation for the development of motor function within the hand.

This timing also allows additional reconstruction for thumb hypoplasia at a relatively early time. Such early intervention takes advantage of the ability of the immature brain to adjust. Children with bilateral deficiencies that affect both the forearm and thumb require staged treatment to gain maximal use of the reconstructed limbs.

Tendon and bony procedures are performed simultaneously to provide better alignment of the forearm and to balance the wrist. Tendon transfers are used to attempt to correct the muscular imbalance and include advancing the extensor carpi ulnaris to increase its moment arm for ulnar deviation and transfer of the flexor carpi ulnaris to the extensor carpi ulnaris.

Other, less common options are transfer of the index and long flexor digitorum superficialis around the ulna to the dorsum of the wrist, transfer of the flexor and extensor carpi radialis to the ulnar side, and proximal advancement of the hypothenar muscles to the ulna.

Bony correction of the ulna consists of a closing-wedge osteotomy when there is considerable (ie, >30°) ulnar bow. Bony reconstruction of the distal radius is more difficult; an attempt is made to provide osseous support to the radial side of the carpus. Initial efforts consisted of nonvascularized transfer of a bone graft (tibia, fibula). These efforts were unsuccessful; continued ulnar growth resulted in loss of support. However, innovative procedures involving microsurgical transfer of a vascularized bone graft along with its growth plate (fibula, second toe) have been encouraging.[32, 33]

Preparation for surgery

The main preoperative emphasis is placed on the status of soft tissues. Stretching and splinting of the taut radial structures is required before surgery. Failure to elongate the tight radial side limits the ability to centralize the wrist on the ulna. Preliminary soft-tissue lengthening with an external fixator is a viable option in cases recalcitrant to stretching (eg, in older children or patients with a recurrent deformity).[34, 35]  A uniplanar or multiplanar device can be used (see the images below).

Uniplanar external fixator. Uniplanar external fixator.
Multiplanar external fixator. Multiplanar external fixator.

Preoperative measurements of the degree of active and passive motion of the digits and wrist are recorded.

Radiographs in the anteroposterior and lateral projection, including the elbow and hand, are obtained. The degree of ulnar bow is calculated from the lateral radiograph as the angle between the proximal and distal ulna (see the image below). Angulation of more than 30° usually necessitates corrective osteotomy at the time of centralization to realign the forearm.

Construction of lines to calculate ulna curvature, Construction of lines to calculate ulna curvature, hand-forearm angle, and total angulation.

Operative details

The basic goals of treatment are as follows[16] :

  • Correct radial deviation of the wrist
  • Balance the wrist on the forearm
  • Maintain wrist and finger motion
  • Promote growth of the forearm
  • Improve function of the extremity
  • Enhance limb appearance for social and emotional benefit

The digital abnormalities also require consideration during formulation of a treatment plan, in that stiff fingers and a deficient thumb will hamper prehension and create an additional functional handicap. Centralization remains the principal procedure to realign the carpus onto the distal ulna and is indicated in types II, III, and IV radial deficiencies (see the image below).

Ulnar incision to centralize carpus and proximal i Ulnar incision to centralize carpus and proximal incision for corrective osteotomy.

Contraindications for surgical intervention are a limited life expectancy in a child, mild deformity with adequate support for the hand (type 1), an elbow extension contracture that prevents the hand from reaching the mouth, and, in adults, adjustment to the deformity.

Centralization is performed at about age 1 year. Multiple surgical approaches have been described. If taut radial structures remain, a radial zigzag incision is performed along the fold between the hand and forearm. This design allows adequate exposure and Z-plasty skin lengthening after centralization.

The anomalous dorsal branch of the enlarged median nerve must be identified in the skin fold at the wrist. Aberrant preaxial musculotendinous units and anomalous contracted fibrous bands are released to allow adequate passive correction of the carpus centered over the ulna.

If there has been preliminary external fixator distraction, a single incision may be made, beginning dorsally at the midline of the wrist and extending ulnarly in a transverse and elliptical fashion to the volar midline. This design provides exposure to the carpus and allows excision of redundant ulnar tissue (see the image below).

Single incision following preliminary external fix Single incision following preliminary external fixation.

The flexor carpi ulnaris and ulnar neurovascular structures are identified and protected. The carpus is exposed by a transverse arthrotomy, and redundant fibrous tissue is excised from the ulnocarpal joint. The carpus is then reduced onto the distal ulna for centralization.

Failure to achieve centralization requires repeat examination for any persistent contracted or fibrotic radial tissue. In severe cases, adequate reduction cannot be achieved, and alternative surgical means are necessary, such as carpectomy, limited shaving of the distal ulna epiphysis while avoiding injury to the growth plate, or shortening osteotomy of the ulna to reduce soft-tissue tension. Another option is application of an external fixator, followed by postoperative distraction and delayed formal centralization.

Soft-tissue stabilization and balancing are performed with dorsal capsular reefing, distal advancement or reefing of the extensor carpi ulnaris insertion, and transfer of the flexor carpi ulnaris to the dorsum. These manipulations redirect the palmar and radial deviating forces to resist recurrence of deformity.

The wrist is held reduced by a Kirschner wire (K-wire), which is placed through the carpus and third metacarpal and into the ulnar shaft. If the ulnar angulation is more than 30°, a diaphyseal closing-wedge osteotomy is performed at the apex of the deformity. The osteotomy is secured with the same K-wire used to maintain centralization. Additional K-wires may be used for added stability.

Numerous technical modifications and advancements have been proposed to sustain a well-aligned wrist position, including correction of the ulnar bow, radialization or overcorrection of the carpus, tendon transfer, capsular plication, and prolonged pin fixation.

Even microvascular free toe transfer to support the radial side of the wrist with a growing part has been advocated.[32]  The toe proximal phalanx is fused to the base of the second metacarpal, and the proximal metatarsal is affixed to the side of the distal ulna. This joint transplantation avoids direct manipulation of the ulnocarpal joint, and the transfer grows at a rate similar to that of the adjacent ulna.

Unfortunately, no method reliably and permanently corrects the radial deviation, balances the wrist, and allows continued growth of the forearm.[16, 36]  Maintenance of the carpus at the end of the ulna without sacrificing wrist mobility or stunting forearm growth remains a daunting task.[37]

Postoperative Care

Immediate active and passive digital motion is initiated, along with measures to reduce swelling. The timing of K-wire removal is controversial. At least 8-10 weeks of fixation is required before removal. Some authors recommend 6 months of fixation before removal.

After K-wire extraction, a splint is made and removed for exercises, with gradual weaning from the splint over the following 4-6 weeks. A nighttime splint regimen is encouraged until skeletal maturity is reached.

Complications

Complications are common after centralization and can occur at the time of surgery or during the postoperative or follow-up period. Many of these complications are minor and do not impact the overall outcome; these include pin-tract irritation and a transient diminution in finger motion.

Recurrence (see the images below) is the most common source of failure after centralization, and the cause appears to be multifactorial. Operative causes of failure include the inability to obtain complete correction at surgery, inadequate radial soft-tissue release, and failure to balance the radial force. Postoperative reasons consist of early pin removal, poor postoperative splint use, and the natural tendency of the shortened forearm and hand to deviate in a radial direction for hand-to-mouth use.

Recurrence after centralization. Recurrence after centralization.
Marked recurrence of radial deviation. Marked recurrence of radial deviation.
Ilizarov device applied for correction of recurren Ilizarov device applied for correction of recurrent deformity.

The application of sophisticated techniques, such as distraction osteogenesis and microsurgery, to the treatment of radial clubhand introduces additional potential complications, such as fracture of the regenerate bone, digital stiffness from lengthening, and vascular thrombosis of the microsurgical anastomosis.

Long-Term Monitoring

Patients with radial deficiencies require follow-up into adulthood. The evaluation should include not only the status of the centralization but also any additional operative and nonoperative needs.[38]  The shortened extremity with diminished motion may not be able to accomplish certain functions. These tasks often can be carried out with the use of assistive devices. In addition, as the child ages, distraction osteogenesis (see the image below) may be an option to increase forearm length.

Forearm lengthening with distraction osteogenesis. Forearm lengthening with distraction osteogenesis.