Kaohsiung J Med Sci March 2007 • Vol 23 • No 3 151 The distal aspect of the radius and ulna is the most
common site of fracture in children. Generally, the mechanism of injury is a fall on an outstretched hand and wrist. The distal fragment usually displaces dor-sally, creating an extension deformity. Neurovascular injury, especially ulnar nerve injury, is rare in fracture of the distal radius in children. To our knowledge, there are only a few cases in the literature that men-tion ulnar nerve injury after distal radius fracture. We report a case of ulnar nerve injury associated with fracture of the distal radius in an adolescent, which recovered spontaneously without any surgical intervention.
C
ASEP
RESENTATIONA 14-year-old boy sustained right wrist pain and deformity after falling on his outstretched hands while playing basketball. He was sent to our emergency room and the radiographs revealed fracture of the right distal radius (Salter–Harris Type II) with dorsal displacement and fracture of the ulnar styloid process with volar protrusion of the distal ulna (Figure 1). The boy complained of numbness over the fourth and fifth digits of his right hand. Initial examination found decreased sensation and weakness in the abduc-tion of the fourth and fifth digits. There was no open wound at the right wrist or any sign of elbow injury. The radial and ulnar pulses were intact. Under gen-eral anesthesia, emergent close reduction with percu-taneous pinning of the fracture was performed in the operation room under fluoroscopic guidance (Figure 2). The next day, he continued to complain of numbness Received: March 23, 2006 Accepted: June 13, 2006
Address correspondence and reprint requests to: Dr Pei-Hsi Chou, Department of Orthopedic Surgery, Kaohsiung Medical University Hospital, 100 Tzyou 1stRoad, Kaohsiung 807, Taiwan. E-mail: [email protected]
U
LNAR
N
ERVE
P
ALSY
F
OLLOWING
F
RACTURE OF
THE
D
ISTAL
R
ADIUS IN AN
A
DOLESCENT
:
A C
ASE
R
EPORT
Cheng-Chang Lu,1Chin-Yi Chuo,2Shen-Kai Chen,2,3Yu-Han Huang,2and Pei-Hsi Chou2,3
1Department of Orthopedic Surgery, Kaohsiung Municipal Hsiao-Kang Hospital, 2Department of Orthopedic Surgery, Kaohsiung Medical University Hospital, and 3Department of Orthopedic Surgery, Faculty of Medicine, College of Medicine,
Kaohsiung Medical University, Kaohsiung, Taiwan.
In adolescents, neurovascular injury, especially ulnar nerve injury, is rare with fracture of the distal radius. We present a 14-year-old boy who sustained fracture of the distal radius in his right wrist, who also had symptoms of ulnar nerve injury. Close reduction with percutaneous pinning and cast to fix the distal radius fracture was done immediately. Then, we decided to observe the recovery of the nerve injury without providing any emergent nerve exploration. Bone union was achieved after 8 weeks of fixation, and the function of the ulnar nerve was restored completely after 16 weeks of observation. The possibility of ulnar nerve injury should be considered following fracture of the distal aspect of the radius, and we recommend observing the recovery of nerve injury, with no need for emergent nerve exploration.
Key Words:adolescent, fracture of distal radius, ulnar nerve injury (Kaohsiung J Med Sci 2007;23:151–5)
C.C. Lu, C.Y. Chuo, S.K. Chen, et al
over the fourth and fifth digits after the pain had diminished. In addition, he was unable to perform extension of the proximal and distal interphalangeal joints, and adduction and abduction of the fourth and fifth digits. We changed the long arm cast to a short arm cast and bivalved it as soon as possible. There was
no contusion injury or limited motion of his elbow. The symptoms of ulnar nerve palsy did not subside during the admission period. We recommended close observation of the symptoms with regular follow-up at our clinic.
The cast and pin were removed after radiographic callus formation about 4 weeks after injury. He used a wrist brace for 8 weeks, and the radiograph showed solid union of the fracture site (Figure 3). At that time, he still complained of persistent numbness in the fourth and fifth digits. In addition, symptoms of ulnar nerve injury such as clawing of the fourth and fifth digits, positive Froment’s sign, and poor intrinsic muscle function were also found. The result of a nerve con-duction velocity (NCV) test confirmed the presence of an ulnar nerve lesion in Guyon’s canal. The patient received regular rehabilitation treatment and the ulnar nerve function recovered gradually. By 16 weeks after the injury, he had regained full sensation over the fourth and fifth digits of the right hand. On physical examination, there was normal intrinsic muscle func-tion and negative Froment’s sign. The boy returned to playing basketball using his right hand without any limitations.
D
ISCUSSIONFracture of the distal radius is a common injury during the adolescent growth spurt. The peak incidence of
A
R
B
Figure 1. A 14-year-old boy with dorsally displaced right distal radius fracture (arrows) and nondisplaced ulna styloid fracture (arrowhead) with volar protrusion of the distal ulna (Salter–Harris Type II): (A) anteroposterior view; (B) lateral view.
R
A B
Figure 2.Close reduction with percutaneous pinning and long arm casting was performed immediately: (A) anteroposterior view; (B) lateral view.
R
B A
Figure 3.Eight weeks after the injury, solid union of the fracture was achieved: (A) anteroposterior view; (B) lateral view.
fracture of the distal radius occurs between the ages 11.5 and 12.5 years for girls and between 13.5 and 14.5 years for boys, which perfectly matches the age of peak velocity of growth of height [1]. Generally, the mechanism of injury is a fall on an outstretched hand and wrist. The distal fragment usually displaces dor-sally, creating an extension deformity that is clinically apparent. Neurovascular injury is uncommon in such fractures, and ulnar nerve injury is even rarer [2]. On reviewing the literature, we found several case reports that describe ulnar nerve injury associated with fracture of the distal radius [3–12]. Ulnar nerve lesions associ-ated with fracture of the distal radius tend to occur more in young adults who have sustained high-impact injury and marked dorsal displacement of the distal fragment than are generally met in patients with Colles’ fracture [8].
Howard stated that ulnar neuropathy associated with wrist injuries might result from: (1) severe con-tusion of the nerve; (2) pressure on the nerve caused by hemorrhage and edema related to the fracture; and (3) intraneural fibrosis in delayed or progressive paralysis [3]. The rarity of ulnar nerve injuries in the wrist is probably due to the anatomic relationship of the ulna nerve in the wrist and forearm. The ulnar nerve runs along the flexor digitorum profundus, under cover of the flexor carpi ulnaris muscle, and becomes superficial at the level of the flexor carpi ulnaris tendon. Then the ulnar nerve passes through Guyon’s canal at the wrist level. The walls of Guyon’s canal consists of the volar carpal ligament palmarly, the transverse carpal ligament dorsally, and the pisi-form and pisohamate ligament laterally [13]. According to anatomic study, Vance and Gelberman [8] and Clarke and Spencer [10] demonstrated that the ulnar nerve has greater excursion in Guyon’s canal than the median nerve in the carpal canal, which may be the reason for the rarity of ulnar nerve injury in wrist injuries.
In this case, the boy had sustained fracture of the distal radius (Salter–Harris Type II) combined with fracture of the tip of the ulnar styloid and volar pro-trusion of the distal ulna. He had numbness over the fourth and fifth digits and loss of intrinsic muscle function of his right hand. NCV test demonstrated that the ulnar nerve lesion was located at Guyon’s canal. Similar to this case, Joshi reported a case of traumatic neuritis of the ulnar nerve associated with Colles’ fracture, and considered that the ulnar nerve
lesion was caused by the fracture of the ulnar styloid process [7]. We suppose that the fracture of the ulnar styloid might imply the possibility of ulnar nerve injury. The function of the ulnar nerve should always be checked before performing close reduction of the fracture of the distal radius and ulna styloid in the emergency room. We recommended close observation of the recovery of ulnar nerve function in this case. To our knowledge, there are no standard procedures of treatment for ulnar nerve injury associated with frac-ture of the distal radius and ulna. However, Vance and Gelberman proposed that Guyon’s canal be explored and decompressed if ulnar nerve function does not improve within 24–36 hours after appropriate frac-ture reduction, even though one patient recovered spontaneously without neurolysis in their series [8]. Poppi et al [9] and Clarke and Spencer [10] stated that the causes of ulnar nerve palsy following frac-tures of the distal radius were associated with serious contusion and dense scar tissue formation around the nerve, and early surgical neurolysis was successful in all patients. On the other hand, Neiman et al presented the case of a 12-year-old boy who sustained a closed fracture of the distal radius and ulna with ulnar nerve palsy that recovered spontaneously 17 weeks after the injury [12]. He concluded that the mechanism of ulnar nerve injury following fracture of the distal radius and ulna was caused by axonotmesis rather than nerve entrapment, and recommended observa-tion of the nerve injury after fracture reducobserva-tion. Ducker stated this same concept: that a contusion of the nerve resulting in neurapraxia or axonotmesis will resolve spontaneously without the need for neurolysis and exploration surgery [14]. We decided to follow Neiman et al’s and Ducker’s suggestion. As we expected, after 16 weeks of observation, the function of the ulnar nerve was restored fully without any deficit of hand function.
In conclusion, the incidence of ulnar nerve injury following fracture of the distal radius and ulna sty-loid in adolescents is rare. However, the possibility of ulnar nerve injury should be taken into consideration, and ulnar nerve function in patients who have sus-tained a fracture of the distal radius should always be checked. Even if ulnar nerve injury is present, we strongly recommend reduction of the displaced frac-ture fragment as soon as possible and observation of the nerve injury with regular follow-up, without any necessity of emergent nerve exploration.
R
EFERENCES1. Bailey DA, Wedge JH, McCulloch RG. Epidemiology of fractures of the distal end of the radius in children associated with growth. J Bone Joint Surg Am 1989;71: 1225–31.
2. Waters PM, Kolettis GJ, Schwend R. Acute median neuropathy following physeal fractures of the distal radius. J Pediatr Orthop 1994;14:173–7.
3. Howard FM. Ulnar-nerve palsy in wrist fractures.
J Bone Joint Surg Am 1961;43:1197–201.
4. Zoega H. Fracture of the lower end of the radius with ulnar nerve palsy. J Bone Joint Surg Br 1966;48:514–6. 5. Frykman G. Fracture of the distal radius including
sequale-shoulder, hand finger syndrome, disturbances in the distal radioulnar joint and impairment of nerve function: a clinical and experimental study. Acta Orthop
Scand 1967;(Suppl 108):1–55.
6. Siegal RS, Weiden I. Combined median and ulnar nerve lesions complicating fractures of the distal radius and ulna. Two case reports. J Trauma 1968;8:1114–8. 7. Joshi BB. An unusual cause of ulnar nerve palsy
associ-ated with Colles’ fracture. Hand 1977;9:76–8.
8. Vance RM, Gelberman RH. Acute ulnar neuropathy
with fractures at the wrist. J Bone Joint Surg Am 1978;60: 962–5.
9. Poppi M, Padovani R, Martinelli P, et al. Fracture of the distal radius with ulnar nerve palsy. J Trauma 1978;18: 278–9.
10. Clarke AC, Spencer RF. Ulnar nerve palsy following fractures of the distal radius: clinical and anatomical studies. J Hand Surg Br 1991;16:438–40.
11. Rychack JS, Kalenack A. Injury to the median and ulnar nerves secondary to fracture of the radius. J Bone Joint
Surg Am 1997;59:414–5.
12. Neiman R, Maiocco B, Deeney VF. Ulnar nerve injury after closed forearm fractures in children. J Pediatr Orthop 1998;18:683–5.
13. Szabo RM. Entrapment and compression neuropathies: ulnar tunnel syndrome. In: Green DP, Hotchkiss RN, Pederson WC, eds. Green’s Operative Hand Surgery, 4th edition. Philadelphia, PA: Churchill Livingstone,
1998:1429–31.
14. Ducker TB. Pathophysiology of peripheral nerve trauma. In: Wilkins RH, Rengachary SS, eds. Neurosurgery. New York: McGraw-Hill, 1996;2:3118.
!"VR==P==OP= !"VR==S==NP= !"#$%&' !"!#$ %&' UMT !"#$NMM
