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Developmental dislocation of the radial head
Developmental dislocation of the radial head Masatoshi Amako, MD, Kazuhiro Masada, MD, Hirofumi Ohno, MD, Yasua ki Inamori, MD, and Takas hi Ha ra, MD, Soitama, Japan
An unusual case of developmental dislocation of the radial head is reported. A 6-year-old boy was referred for evaluation of his elbow and was diagnosed as having an anterior dislocation of the right radial head. No dislocation was present on the left. Subsequently, the left radial head dislocated anteriorly without associated trauma 7 year after the initial examination. Intraoperative findings on the right revealed the dislocation occurred during pronation of the forearm when the radius abutted the interosseous border of the ulna. Ulnar osteomy and reinstruction of the annular fragment were performed but were not effective in preventing redislocation. (J SHOULDER ELBOW SURG 7994;3: 769-72.) Developmental dislocation of the radial head is defined as any dislocation of the radial head resulting from a maldevelopment caused by a disease process affecting growth. However, it is often difficult to differentiate a developmental dislocation from that which is congenital. Presented is an unusual case of developmental dislocation of the radial head with an unknown cause. Intraoperative findings revealed the dislocation occurred during pronation of the forearm when the radius abutted the interosseous border of the ulnar shaft.
CASE REPORT A 6-year-old boy with a 12-month history of swelling over the anterior aspect of right elbow was referred to the Hand Clinic at the National Defense Medical College Hospital. On examination there was no visible deformity in the elbow, the forearm, or the wrist, but on palpation the right radial head was located anteriorly and laterally. Wrist and elbow movements were normal, as were the carrying angles of the elbows. There was no instability on varus From the Department of Orthopaedic Surgery , National Defense Medical College, Saitomo. Reprint requests : Masatosh i Amo ko, MD, Department of O rthopoedic Surgery, National Defense Medical College, 32 Namiki, Tokorozawa, Saitamo 359 , Japan. Copyright © 1994 by Journ al of Shoulder & Elbow Surgery Board of Trustees. 1058-2746/94/$3.00 + 0 32/4/50906
or valgus stress of either elbow joint. Radiographs of the elbows revealed an anterior dislocation of the right radial head (Figure 1, A) . The left elbow showed no evidence of radial head dislocation; however, slight subluxation was observed (Figure 1, 8). Both radial heads had a normal radiographic appearance. The patient had no history of trauma. No family members had this abnormality. The patient had no other associated anomalies, nor was there general ' joint laxity. Laboratory findings and chromosomal patterns were normal. Given the diagnosis of a nontraumatic, isolated dislocation of the radial head, open reduction was performed. Intraoperative findings revealed a completely dislocated radial head. with an elongated annular ligament. The radial head could be reduced by supination of the elbow, but it dislocated with pronation of the forearm when the radius abutted the interosseous border of the ulna. Operation consisted of a flexion osteotomy of the proximal ulna with annular ligament reconstruction with the palmaris longus tendon (Figure 2). The dislocated radial head was reduced by flexion osteotomy of the proximal ulna. Reduction was maintained during rotation of the forearm. A long-arm cast was applied for 4 weeks, and gentle range-ofmotion exercise was started. Nevertheless, the dislocation recurred 1 month after the operation . During the follow-up period the patient complained of anterior swelling over the left
169
, 70
Amoko et
01.
J. Shoulder Elbow Surg. May/ June 1994
Figure 1 Roentgenogram taken during first visit. Right radial head was completely dislocated (A), but left was not (B).
elbow. Radiographs revealed a dislocated left radial head (Figure 3). Therefore the patient had dislocated both radial heads; however, he had no pain or restriction of motion in either elbow.
DISCUSSION In a patient that presents with an existing dislocation of the radial head, it is difficult to know
when dislocation occurred. In this case dislocation of the left radial head can clearly be classified as developmentol.': 2 This is because it occurred without associated trauma during the follow-up period. l.etts" has described the causes of developmental dislocation of the radial head. These include nail-patella syndrome, Silver syndrome, arthrogryposis, Cornelia de Lange syndrome,
J. Shoulder Elbow Surg. Volume 3, Number 3
Amako at al.
171
Figure 2 Roentgenogram of right elbow 1 year after operation . Radial head is again d islocated.
Figure 3 Roentgenogram of left elbow 1 year after initial visit. Radial head is completely dislocated . Compare with Figure 1, B. cleidocranial dysosthosis, multiple exostoses, paralysis of muscles innervated by the C5-6 nerve roots, and cerebral palsy.4-6The case presented demonstrated no such skeletal abnormalities nor nerve palsy. Perhaps the dislocation of the radial head observed in this case was caused by the interosseous border of the ulnar shaft. Because the radius is likely to abut
while crossing the ulnar protuberance during rotation of the forearm, the annular ligament may become lax with time . Unfortunately, the treatment offered was not effective. Given the lack of depth in understanding this problem and the low level of symptoms this patient had, we would currently recommend nonoperative treatment for this problem .
172 Amoko et 01.
J. Shoulder Elbow Surg. May/June 1994
The authors thank Professor Masayuki Shinmei, MD, for his advice.
REFERENCES 1. Good CJ, Wicks MH. Developmental posterior dislocation of the radial head. J Bone Joint Surg [Br] 1983;65B:64-5. 2. Lloyd-RobertsGC, Bucknill TM. Anterior dislocation of the radial head in children. J Bone Joint Surg [Br] 1977;59B:402-7.
3. Letts M. Dislocations of the child's elbow. In: Morrey B, ed. The elbow and its disorders. Philadelphia: WB Saunders, 1985:260-88. 4. Peeters HM. Radiological manifestations of the Cornelia de Lange Syndrome. Pediatr Radiol 1975;3:41-6. 5. Pletcher D, Hoffer MM, Koffman DM. Nontraumatic dislocation of the radial head in cerebral palsy. J Bone Joint Surg [Am] 1976;58A:104-5. 6. Wiley JJ, Loehr J, Mcintyre M. Isolated dislocation of the radial head. Ortho Rev 1991 ;20:973-6.
Bound Volumes Available to Subscribers Bound volumes of the 1994 issues of JOURNAL OF SHOULDER AND ELBOW SURGERY are available to subscribers (only) from the publisher, at a cost of $51.50 for domestic, $61.11 for Canadian, and $57.50 for international subscribers, for Vol. 1 (January-December); shipping charges are included. Each bound volume contains subject and author indexes, and all advertising is removed. Copies are shipped within 60 days after publication of the last issue in the volume. The binding is durable buckram, with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact Mosby, Subscription Services, 11830 Westline Industrial Dr., St. Louis, MO 63146-3318, USA; phone (314)453-4351 or (800)453-4351.
Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular subscription.
An unusual case of developmental dislocation of the radial head is reported. A 6-year-old boy was referred for evaluation of his elbow and was diagnosed as having an anterior dislocation of the right radial head. No dislocation was present on the left. Subsequently, the left radial head dislocated anteriorly without associated trauma 7 year after the initial examination. Intraoperative findings on the right revealed the dislocation occurred during pronation of the forearm when the radius abutted the interosseous border of the ulna. Ulnar osteomy and reinstruction of the annular fragment were performed but were not effective in preventing redislocation. (J SHOULDER ELBOW SURG 7994;3: 769-72.) Developmental dislocation of the radial head is defined as any dislocation of the radial head resulting from a maldevelopment caused by a disease process affecting growth. However, it is often difficult to differentiate a developmental dislocation from that which is congenital. Presented is an unusual case of developmental dislocation of the radial head with an unknown cause. Intraoperative findings revealed the dislocation occurred during pronation of the forearm when the radius abutted the interosseous border of the ulnar shaft.
CASE REPORT A 6-year-old boy with a 12-month history of swelling over the anterior aspect of right elbow was referred to the Hand Clinic at the National Defense Medical College Hospital. On examination there was no visible deformity in the elbow, the forearm, or the wrist, but on palpation the right radial head was located anteriorly and laterally. Wrist and elbow movements were normal, as were the carrying angles of the elbows. There was no instability on varus From the Department of Orthopaedic Surgery , National Defense Medical College, Saitomo. Reprint requests : Masatosh i Amo ko, MD, Department of O rthopoedic Surgery, National Defense Medical College, 32 Namiki, Tokorozawa, Saitamo 359 , Japan. Copyright © 1994 by Journ al of Shoulder & Elbow Surgery Board of Trustees. 1058-2746/94/$3.00 + 0 32/4/50906
or valgus stress of either elbow joint. Radiographs of the elbows revealed an anterior dislocation of the right radial head (Figure 1, A) . The left elbow showed no evidence of radial head dislocation; however, slight subluxation was observed (Figure 1, 8). Both radial heads had a normal radiographic appearance. The patient had no history of trauma. No family members had this abnormality. The patient had no other associated anomalies, nor was there general ' joint laxity. Laboratory findings and chromosomal patterns were normal. Given the diagnosis of a nontraumatic, isolated dislocation of the radial head, open reduction was performed. Intraoperative findings revealed a completely dislocated radial head. with an elongated annular ligament. The radial head could be reduced by supination of the elbow, but it dislocated with pronation of the forearm when the radius abutted the interosseous border of the ulna. Operation consisted of a flexion osteotomy of the proximal ulna with annular ligament reconstruction with the palmaris longus tendon (Figure 2). The dislocated radial head was reduced by flexion osteotomy of the proximal ulna. Reduction was maintained during rotation of the forearm. A long-arm cast was applied for 4 weeks, and gentle range-ofmotion exercise was started. Nevertheless, the dislocation recurred 1 month after the operation . During the follow-up period the patient complained of anterior swelling over the left
169
, 70
Amoko et
01.
J. Shoulder Elbow Surg. May/ June 1994
Figure 1 Roentgenogram taken during first visit. Right radial head was completely dislocated (A), but left was not (B).
elbow. Radiographs revealed a dislocated left radial head (Figure 3). Therefore the patient had dislocated both radial heads; however, he had no pain or restriction of motion in either elbow.
DISCUSSION In a patient that presents with an existing dislocation of the radial head, it is difficult to know
when dislocation occurred. In this case dislocation of the left radial head can clearly be classified as developmentol.': 2 This is because it occurred without associated trauma during the follow-up period. l.etts" has described the causes of developmental dislocation of the radial head. These include nail-patella syndrome, Silver syndrome, arthrogryposis, Cornelia de Lange syndrome,
J. Shoulder Elbow Surg. Volume 3, Number 3
Amako at al.
171
Figure 2 Roentgenogram of right elbow 1 year after operation . Radial head is again d islocated.
Figure 3 Roentgenogram of left elbow 1 year after initial visit. Radial head is completely dislocated . Compare with Figure 1, B. cleidocranial dysosthosis, multiple exostoses, paralysis of muscles innervated by the C5-6 nerve roots, and cerebral palsy.4-6The case presented demonstrated no such skeletal abnormalities nor nerve palsy. Perhaps the dislocation of the radial head observed in this case was caused by the interosseous border of the ulnar shaft. Because the radius is likely to abut
while crossing the ulnar protuberance during rotation of the forearm, the annular ligament may become lax with time . Unfortunately, the treatment offered was not effective. Given the lack of depth in understanding this problem and the low level of symptoms this patient had, we would currently recommend nonoperative treatment for this problem .
172 Amoko et 01.
J. Shoulder Elbow Surg. May/June 1994
The authors thank Professor Masayuki Shinmei, MD, for his advice.
REFERENCES 1. Good CJ, Wicks MH. Developmental posterior dislocation of the radial head. J Bone Joint Surg [Br] 1983;65B:64-5. 2. Lloyd-RobertsGC, Bucknill TM. Anterior dislocation of the radial head in children. J Bone Joint Surg [Br] 1977;59B:402-7.
3. Letts M. Dislocations of the child's elbow. In: Morrey B, ed. The elbow and its disorders. Philadelphia: WB Saunders, 1985:260-88. 4. Peeters HM. Radiological manifestations of the Cornelia de Lange Syndrome. Pediatr Radiol 1975;3:41-6. 5. Pletcher D, Hoffer MM, Koffman DM. Nontraumatic dislocation of the radial head in cerebral palsy. J Bone Joint Surg [Am] 1976;58A:104-5. 6. Wiley JJ, Loehr J, Mcintyre M. Isolated dislocation of the radial head. Ortho Rev 1991 ;20:973-6.
Bound Volumes Available to Subscribers Bound volumes of the 1994 issues of JOURNAL OF SHOULDER AND ELBOW SURGERY are available to subscribers (only) from the publisher, at a cost of $51.50 for domestic, $61.11 for Canadian, and $57.50 for international subscribers, for Vol. 1 (January-December); shipping charges are included. Each bound volume contains subject and author indexes, and all advertising is removed. Copies are shipped within 60 days after publication of the last issue in the volume. The binding is durable buckram, with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact Mosby, Subscription Services, 11830 Westline Industrial Dr., St. Louis, MO 63146-3318, USA; phone (314)453-4351 or (800)453-4351.
Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular subscription.