CONGENITAL
DISLOCATION
OF THE
RADIAL
HEAD
T. MIURA From the Department oforthopaedic Surgery, Nagoya University Scholl of Medicine, Japan A retrospective review of 34 patients with congenital dislocation of the radial head was carried out. In 22 patients, the radial head dislocation was the only abnormality. The range of motion of the elbow and forearm was considerably limited iu some patients and did cause functional impairment, especially lack of supination. Increased ulnar length in relation to the radius and a hypoplastic capitellum suggest that a dislocation is congenital. Surgical intervention is seldom necessary. Journal of Hand Surgery (British Volume, 1990) 15B: 477-481
Congenital dislocation of the radial head, thought to be rare, is in fact a relatively common anomaly and is welldescribed in the orthopaedic literature. However, there are differences in the reports as to the frequency of different types of dislocations, the limitation in the range of motion of the elbow and forearm, associated anomalies, X-ray appearances and causes of congenital dislocation. A retrospective review has been undertaken to clarify some of these points.
9
I
8
Clinical cases 34 patients diagnosed as having congenital dislocation of the radial head were seen at our clinic between 1968 and 1988. 19 were males and 15 females. 11 patients had biIatera1 dislocation. Of the 23 unilateral cases, 14 were on the right side and nine on the left. Four patients had radio-ulnar synostosis in the other elbow joint. Of the 34 patients, three who also had ulnar or radial ray defects came to our clinic within one month after birth, but of 22 patients with no other anomaly, only two came within the first year after birth: 15 were over ten years of age when first seen (Fig. 1). The dislocation in 45 elbows of 34 patients was posterior in 20 (16 patients), anterior in 24 (19 patients) and lateral in one. In two bilateral cases, the dislocation was posterior on one side and anterior in the other. Nine of the patients also had other anomalies of the upper limb. In three patients with ulnar ray defects (one with an associated thumb defect), two with clasped thumbs and one with a hypoplastic thumb, the dislocation was anterior. In one patient with a thumb defect and constriction band syndrome, one with transverse failure of formation and one with mirror hand, the dislocation was posterior. Three patients had anomalies other than those of the upper extremity. Two had dislocation of the patella, one of whom had typical nail-patella syndrome. In one patient with dislocation of the patella, the dislocation was posterior in both elbows, but in the other one the dislocation was posterior on the right and anterior on the left (Fig. 2). Torticollis was noted in one patient with posterior dislocation. Several of our patients complained of impaired flexion and extension of the elbow joint and impaired supination VOL. 15B No. 4 NOVEMBER
1990
-
lm
ly
5y
1oy 2oy
3oy
lm
llm
4y
9y
19y 29y
-
Fig. 1 The age distribution at first visit to our clinic.
and pronation of the forarm. The severity and direction (flexion or extension) of restriction of movement differed case by case and there was no pattern of impairment, whether the dislocation was posterior or anterior (Fig. 3, 4). X-ray findings
In anterior congenital dislocations, the posterior border of the ulna is concave, rather than slightly convex as seen normally. The radial head is dome-shaped with no central depression. Posterior congenital dislocation is characterised by elongated and thinned contours to the radial head. The normal convexity of the posterior border of the ulna is accentuated (Fig. 5). Although, these X-ray findings were the most characteristic in this series, hypoplasia of the capitellum (Fig. 6) and shortness of the ulna (Fig. 7) were also seen. Developmentally, a hypo411
T. MIURA
Fig. 2
The case with congenital
dislocation
of the patella:
posterior
dislocation
in the right elbow and anterior
dislocation
in the left.
plastic, under-developed capitellum and short ulna are both considered to be distinctive features of congenital dislocation of the radial head. The Baumann’s angle (Baumann, 1929) for a child and humeral angle (Keats et al., 1966) for a grown-up patient were measured. The former was enlarged or could not be measured due to
-
I
+
-
I
I
I
c
I
I
50" Fig. 3
418
Ranges of flexion and extension
loo0
150"
of the elbow joint.
pronation 50’
Fig. 4
Ranges of supination
I
0 and pronation
50”
supination
of the forearm.
THE JOURNAL
OF HAND SURGERY
CONGENITAL
Fig. 6
Hypoplasia
of the capitellum:
(a) Baumann
DISLOCATION
angle 50” on right, 33” on left. (b) Humeral
developmental failure of the epiphyses. The latter was also enlarged. The humeral angle on the dislocated side was increased, being more than 90”: according to Keats et al. (1966) the average is 85” in males and 83” in females. VOL. 15B No. 4 NOVEMBER
1990
OF THE RADIAL
HEAD
angle 115” on right,
109” on left.
The humeral angle was increased not only on the dislocated side but also on the undislocated side. The angle of the undislocated side, in six out of eight cases, exceeded 90” (Fig. 8). 419
T. MIURA
Fig 7
Shortness
of the ulna compared
with the radius
Treatment
Reposition of the anteriorly dislocated radial head by rotational osteotomy of the radius and wedge osteotomy of the ulna was carried out in two patients, but was successful in only one. Little functional improvement was gained. The radial head was excised in one patient, which removed the bony prominence and relieved pain but did not increase movement of the forearm or elbow. Discussion
According to Mardam-Bey and Ger (1979), all cases with no other anomaly were bilateral. However, much lower incidences of bilateral cases were reported by Almquist et al. (1969) who found 42% and by Ogino et al. (1982) who had 6 out of 13 cases. In our series, 11 patients out of 34 had bilateral dislocation. White (1942) stated that in no reported case was there an abnormality at birth, but Caravias (1957), Cockshott and Omololu (1958), Schubert (1965) and others have described cases with definite deformity at or soon after birth. Of our 34 patients, three with ulnar or radial ray 480
defects together with congenital radial head dislocation came to our clinic within one month of birth. Of 22 patients with no other anomaly, only two came within the first year and 15 were over ten when first seen. The reason why few patients are diagnosed at or soon after birth is that the impairment in daily life is minimal, not that the dislocation develops late. Some authors (Almquist et al., 1969; Mital, 1976) consider that radial head dislocations associated with other anomalies are posterior in most cases. However, in one of our patients with dislocation of the patella, the dislocation of the both elbows was posterior, but in another the dislocation was posterior on the right and was anterior on the left. Although, Mital (1976), Mardam-Bey and Ger (1979) and Kelly (198 1) found most patients with dislocation of the radial head to have minimal functional impairment, several of our patients complained of restricted flexion and extension of the elbow joint and supination and pronation of the forearm. Almquist et al. (1969) and Mital(1976) maintain that in anterior dislocation, flexion and supination may be impaired, while in posterior THE JOURNAL
OF HAND SURGERY
CONGENITAL
DISLOCATION
? ? dislocated @
RADIAL
HEAD
ligament, which was suggested by McFarland (1936), Almquist (1969) and Mital(1976), has not been uniformly successful. Resection of the radial head after skeletal maturity has been suggested by some authors (Mital, 1976, Mardam-Bey and Ger, 1979, Kelly, 1981), but Almquist et al. (1969) were worried about loss of stability and the development of cubitus valgus after resection of the radial head. In the majority of cases, surgical treatment is not required but, if pain and limitation of motion are troublesome in an adult patient, resection of the radial head is safe and reliable.
10
I
OF THE
side undislocated side
Conclusions
84’ Fig. 8
Humeral
850
900
950
1000
1050
1100
89’
94’
99”
104’
109’
-
angle.
dislocation, extension and pronation may be impaired, but the findings in our patients were variable and did not support any such rule. Many authors (McFarland, 1936; Caravias, 1957; Mital, 1976; Almquist et al., 1969; Abe et al., 1978; Ogino et al., 1982) have pointed out that in anterior congenital dislocations, the posterior border of the ulna is concave rather than slightly convex as it is normally. The radial head is dome-shaped with no central depression. Posterior congenital dislocation is characterised by elongated and thinned contours to the radial head and the normal convexity of the posterior border of the ulna is accentuated. These findings were also found in this series. However the abnormal convexity of the posterior border of the ulna and the dome-shaped radial head may be a result of long-standing dislocation of the radial head. Hypoplasia of the capitellum and shortness of the ulna were also characteristic findings, as reported by many authors (Almquist et al., 1969; Mital, 1976; Ogino et al., 1982). The Baumann’s angle (1929) was enlarged or could not be measured due to developmental failure of the epiphyses. The humeral angle (Keats et al., 1966) was also enlarged. Although the humeral angle on the dislocated side had increased more than on the undislocated side, the angle of the undislocated side exceeded 90” in six of eight cases. The shortness of the ulna was remarkable, not only in typical ulnar ray deficiency, but in patients with simple congenital dislocation of the radial head. The underdeveloped humeral capitellum on the unaffected side and the short ulna suggest that congenital dislocation of the radius may be the result of defective development of the elbow joint. We believe that a hypoplastic underdeveloped capitulum and a short ulna both contribute to congenital dislocation of the radial head. There are very few indications for surgical intervention. Early reduction and reconstruction of the annular VOL.
15B No. 4 NOVEMBER
1990
1. Most patients with dislocation of the radial head have some functional impairment, especially lack of supination. 2. The extent and direction of impairment in motion do not depend on whether the dislocation is anterior or posterior. 3. Anterior dislocation does occur in cases with other malformations. 4. The characteristic underdeveloped humeral capitellum and short ulna show that the dislocation is congenital. 5. Defective development of the elbow joint may be the primary cause of congenital dislocation of the radial head. References ABE. M.. IKEDA. K.. KINOSITA. M. and YASUNAGA. H. (1978). Dislocation of tie radial iead in children. Seikeigeka, 29: 13: 1352-1358 (in Japanese). ALMQUIST, E. E., GORDON, L. H. and BLUE, A. I. (1969). Congenital Dislocation of the Head of the Radius. Journal of Bone and Joint Surgery, 51A:6: 1118-1127. BAUMANN,E. (1929). BeitrXgezurKenntnisderFrakturenamEllbogengelenk. Unter besonderer Beriicksichtigung der SpLtfolgen. 1. Allgemeines und Fractura supra condylica. Beitragen zur Klinischen Chirurgie, 146: 1: l-50. CARAVIAS, D. E. (1957). Some observation on congenital dislocation of the head of the radius. Journal of Bone and Joint Surgery, 39B: 1: 86-90. COCKSHOTT, W. P. and OMOLOLU, A. (1958). Familial congenital posterior dislocation of both radial heads. Journal of Bone and Joint Surgery, 40B: 3: 483486. KEATS, T. E., TEESLINK, R., DIAMOND, A. E. and WILLIAMS, J. H. (1966). Normal Axial Relationships of the Major Joints. Radiology, 87: 5: 904-907. KELLY, D. W. (1981). Congenital Dislocation of the Radial Head: Spectrum and Natural History. Journal of Pediatric Orthopedics, 1: 3: 295-298. MARDAM-BEY, T. and GER, E. (1979). Congenital radial head dislocation. Journal of Hand Surgery, 4: 4: 316320. MCFARLAND; B. (1936). Congenital dislocation of the head of the radius. British Journal of Surgery, 24: 41-49. MITAL, M. A. (1976). Congenital Radioulnar Synostosis and Congenital Dislocation of the Radial Head. Orthopedic Clinics of North America, 7: 2: 375-383. OGINO, T., ISHII, S., USUI, M., MINAMI, A., HUKUTA, K. and KATOU, S. (1982). Clinical feature of the so-called congenital radial head dislocation. Rinshou-Seikeigeka 17: 5: 439-445 (in Japanese). SCHUBERT, M. J. J. (1965). Dislocation of the Radial Head in the Newborn Infant. Journal of Bone and Joint Surgery, 47A: 5: 1019-1023. WHITE, J. R. A. (1942). Congenital dislocation of the head ofthe radius. British Journal of Surgery, 30: 377-379. Accepted: 22 August 1989 Takayuki Miura, M.D. DepartmentofOrthopaedicSurgery, 466, Japan. 0
1990 The British
Society
NagoyaUniversity, for Surgery
65 Turuma-cho,
Showak-ku,
Nagoya,
of the Hand
0266-7681/90/0015XI477/$10.00
481
DISLOCATION
OF THE
RADIAL
HEAD
T. MIURA From the Department oforthopaedic Surgery, Nagoya University Scholl of Medicine, Japan A retrospective review of 34 patients with congenital dislocation of the radial head was carried out. In 22 patients, the radial head dislocation was the only abnormality. The range of motion of the elbow and forearm was considerably limited iu some patients and did cause functional impairment, especially lack of supination. Increased ulnar length in relation to the radius and a hypoplastic capitellum suggest that a dislocation is congenital. Surgical intervention is seldom necessary. Journal of Hand Surgery (British Volume, 1990) 15B: 477-481
Congenital dislocation of the radial head, thought to be rare, is in fact a relatively common anomaly and is welldescribed in the orthopaedic literature. However, there are differences in the reports as to the frequency of different types of dislocations, the limitation in the range of motion of the elbow and forearm, associated anomalies, X-ray appearances and causes of congenital dislocation. A retrospective review has been undertaken to clarify some of these points.
9
I
8
Clinical cases 34 patients diagnosed as having congenital dislocation of the radial head were seen at our clinic between 1968 and 1988. 19 were males and 15 females. 11 patients had biIatera1 dislocation. Of the 23 unilateral cases, 14 were on the right side and nine on the left. Four patients had radio-ulnar synostosis in the other elbow joint. Of the 34 patients, three who also had ulnar or radial ray defects came to our clinic within one month after birth, but of 22 patients with no other anomaly, only two came within the first year after birth: 15 were over ten years of age when first seen (Fig. 1). The dislocation in 45 elbows of 34 patients was posterior in 20 (16 patients), anterior in 24 (19 patients) and lateral in one. In two bilateral cases, the dislocation was posterior on one side and anterior in the other. Nine of the patients also had other anomalies of the upper limb. In three patients with ulnar ray defects (one with an associated thumb defect), two with clasped thumbs and one with a hypoplastic thumb, the dislocation was anterior. In one patient with a thumb defect and constriction band syndrome, one with transverse failure of formation and one with mirror hand, the dislocation was posterior. Three patients had anomalies other than those of the upper extremity. Two had dislocation of the patella, one of whom had typical nail-patella syndrome. In one patient with dislocation of the patella, the dislocation was posterior in both elbows, but in the other one the dislocation was posterior on the right and anterior on the left (Fig. 2). Torticollis was noted in one patient with posterior dislocation. Several of our patients complained of impaired flexion and extension of the elbow joint and impaired supination VOL. 15B No. 4 NOVEMBER
1990
-
lm
ly
5y
1oy 2oy
3oy
lm
llm
4y
9y
19y 29y
-
Fig. 1 The age distribution at first visit to our clinic.
and pronation of the forarm. The severity and direction (flexion or extension) of restriction of movement differed case by case and there was no pattern of impairment, whether the dislocation was posterior or anterior (Fig. 3, 4). X-ray findings
In anterior congenital dislocations, the posterior border of the ulna is concave, rather than slightly convex as seen normally. The radial head is dome-shaped with no central depression. Posterior congenital dislocation is characterised by elongated and thinned contours to the radial head. The normal convexity of the posterior border of the ulna is accentuated (Fig. 5). Although, these X-ray findings were the most characteristic in this series, hypoplasia of the capitellum (Fig. 6) and shortness of the ulna (Fig. 7) were also seen. Developmentally, a hypo411
T. MIURA
Fig. 2
The case with congenital
dislocation
of the patella:
posterior
dislocation
in the right elbow and anterior
dislocation
in the left.
plastic, under-developed capitellum and short ulna are both considered to be distinctive features of congenital dislocation of the radial head. The Baumann’s angle (Baumann, 1929) for a child and humeral angle (Keats et al., 1966) for a grown-up patient were measured. The former was enlarged or could not be measured due to
-
I
+
-
I
I
I
c
I
I
50" Fig. 3
418
Ranges of flexion and extension
loo0
150"
of the elbow joint.
pronation 50’
Fig. 4
Ranges of supination
I
0 and pronation
50”
supination
of the forearm.
THE JOURNAL
OF HAND SURGERY
CONGENITAL
Fig. 6
Hypoplasia
of the capitellum:
(a) Baumann
DISLOCATION
angle 50” on right, 33” on left. (b) Humeral
developmental failure of the epiphyses. The latter was also enlarged. The humeral angle on the dislocated side was increased, being more than 90”: according to Keats et al. (1966) the average is 85” in males and 83” in females. VOL. 15B No. 4 NOVEMBER
1990
OF THE RADIAL
HEAD
angle 115” on right,
109” on left.
The humeral angle was increased not only on the dislocated side but also on the undislocated side. The angle of the undislocated side, in six out of eight cases, exceeded 90” (Fig. 8). 419
T. MIURA
Fig 7
Shortness
of the ulna compared
with the radius
Treatment
Reposition of the anteriorly dislocated radial head by rotational osteotomy of the radius and wedge osteotomy of the ulna was carried out in two patients, but was successful in only one. Little functional improvement was gained. The radial head was excised in one patient, which removed the bony prominence and relieved pain but did not increase movement of the forearm or elbow. Discussion
According to Mardam-Bey and Ger (1979), all cases with no other anomaly were bilateral. However, much lower incidences of bilateral cases were reported by Almquist et al. (1969) who found 42% and by Ogino et al. (1982) who had 6 out of 13 cases. In our series, 11 patients out of 34 had bilateral dislocation. White (1942) stated that in no reported case was there an abnormality at birth, but Caravias (1957), Cockshott and Omololu (1958), Schubert (1965) and others have described cases with definite deformity at or soon after birth. Of our 34 patients, three with ulnar or radial ray 480
defects together with congenital radial head dislocation came to our clinic within one month of birth. Of 22 patients with no other anomaly, only two came within the first year and 15 were over ten when first seen. The reason why few patients are diagnosed at or soon after birth is that the impairment in daily life is minimal, not that the dislocation develops late. Some authors (Almquist et al., 1969; Mital, 1976) consider that radial head dislocations associated with other anomalies are posterior in most cases. However, in one of our patients with dislocation of the patella, the dislocation of the both elbows was posterior, but in another the dislocation was posterior on the right and was anterior on the left. Although, Mital (1976), Mardam-Bey and Ger (1979) and Kelly (198 1) found most patients with dislocation of the radial head to have minimal functional impairment, several of our patients complained of restricted flexion and extension of the elbow joint and supination and pronation of the forearm. Almquist et al. (1969) and Mital(1976) maintain that in anterior dislocation, flexion and supination may be impaired, while in posterior THE JOURNAL
OF HAND SURGERY
CONGENITAL
DISLOCATION
? ? dislocated @
RADIAL
HEAD
ligament, which was suggested by McFarland (1936), Almquist (1969) and Mital(1976), has not been uniformly successful. Resection of the radial head after skeletal maturity has been suggested by some authors (Mital, 1976, Mardam-Bey and Ger, 1979, Kelly, 1981), but Almquist et al. (1969) were worried about loss of stability and the development of cubitus valgus after resection of the radial head. In the majority of cases, surgical treatment is not required but, if pain and limitation of motion are troublesome in an adult patient, resection of the radial head is safe and reliable.
10
I
OF THE
side undislocated side
Conclusions
84’ Fig. 8
Humeral
850
900
950
1000
1050
1100
89’
94’
99”
104’
109’
-
angle.
dislocation, extension and pronation may be impaired, but the findings in our patients were variable and did not support any such rule. Many authors (McFarland, 1936; Caravias, 1957; Mital, 1976; Almquist et al., 1969; Abe et al., 1978; Ogino et al., 1982) have pointed out that in anterior congenital dislocations, the posterior border of the ulna is concave rather than slightly convex as it is normally. The radial head is dome-shaped with no central depression. Posterior congenital dislocation is characterised by elongated and thinned contours to the radial head and the normal convexity of the posterior border of the ulna is accentuated. These findings were also found in this series. However the abnormal convexity of the posterior border of the ulna and the dome-shaped radial head may be a result of long-standing dislocation of the radial head. Hypoplasia of the capitellum and shortness of the ulna were also characteristic findings, as reported by many authors (Almquist et al., 1969; Mital, 1976; Ogino et al., 1982). The Baumann’s angle (1929) was enlarged or could not be measured due to developmental failure of the epiphyses. The humeral angle (Keats et al., 1966) was also enlarged. Although the humeral angle on the dislocated side had increased more than on the undislocated side, the angle of the undislocated side exceeded 90” in six of eight cases. The shortness of the ulna was remarkable, not only in typical ulnar ray deficiency, but in patients with simple congenital dislocation of the radial head. The underdeveloped humeral capitellum on the unaffected side and the short ulna suggest that congenital dislocation of the radius may be the result of defective development of the elbow joint. We believe that a hypoplastic underdeveloped capitulum and a short ulna both contribute to congenital dislocation of the radial head. There are very few indications for surgical intervention. Early reduction and reconstruction of the annular VOL.
15B No. 4 NOVEMBER
1990
1. Most patients with dislocation of the radial head have some functional impairment, especially lack of supination. 2. The extent and direction of impairment in motion do not depend on whether the dislocation is anterior or posterior. 3. Anterior dislocation does occur in cases with other malformations. 4. The characteristic underdeveloped humeral capitellum and short ulna show that the dislocation is congenital. 5. Defective development of the elbow joint may be the primary cause of congenital dislocation of the radial head. References ABE. M.. IKEDA. K.. KINOSITA. M. and YASUNAGA. H. (1978). Dislocation of tie radial iead in children. Seikeigeka, 29: 13: 1352-1358 (in Japanese). ALMQUIST, E. E., GORDON, L. H. and BLUE, A. I. (1969). Congenital Dislocation of the Head of the Radius. Journal of Bone and Joint Surgery, 51A:6: 1118-1127. BAUMANN,E. (1929). BeitrXgezurKenntnisderFrakturenamEllbogengelenk. Unter besonderer Beriicksichtigung der SpLtfolgen. 1. Allgemeines und Fractura supra condylica. Beitragen zur Klinischen Chirurgie, 146: 1: l-50. CARAVIAS, D. E. (1957). Some observation on congenital dislocation of the head of the radius. Journal of Bone and Joint Surgery, 39B: 1: 86-90. COCKSHOTT, W. P. and OMOLOLU, A. (1958). Familial congenital posterior dislocation of both radial heads. Journal of Bone and Joint Surgery, 40B: 3: 483486. KEATS, T. E., TEESLINK, R., DIAMOND, A. E. and WILLIAMS, J. H. (1966). Normal Axial Relationships of the Major Joints. Radiology, 87: 5: 904-907. KELLY, D. W. (1981). Congenital Dislocation of the Radial Head: Spectrum and Natural History. Journal of Pediatric Orthopedics, 1: 3: 295-298. MARDAM-BEY, T. and GER, E. (1979). Congenital radial head dislocation. Journal of Hand Surgery, 4: 4: 316320. MCFARLAND; B. (1936). Congenital dislocation of the head of the radius. British Journal of Surgery, 24: 41-49. MITAL, M. A. (1976). Congenital Radioulnar Synostosis and Congenital Dislocation of the Radial Head. Orthopedic Clinics of North America, 7: 2: 375-383. OGINO, T., ISHII, S., USUI, M., MINAMI, A., HUKUTA, K. and KATOU, S. (1982). Clinical feature of the so-called congenital radial head dislocation. Rinshou-Seikeigeka 17: 5: 439-445 (in Japanese). SCHUBERT, M. J. J. (1965). Dislocation of the Radial Head in the Newborn Infant. Journal of Bone and Joint Surgery, 47A: 5: 1019-1023. WHITE, J. R. A. (1942). Congenital dislocation of the head ofthe radius. British Journal of Surgery, 30: 377-379. Accepted: 22 August 1989 Takayuki Miura, M.D. DepartmentofOrthopaedicSurgery, 466, Japan. 0
1990 The British
Society
NagoyaUniversity, for Surgery
65 Turuma-cho,
Showak-ku,
Nagoya,
of the Hand
0266-7681/90/0015XI477/$10.00
481
