Diagnosing and treating traumatic hand and wrist injuries can be challenging for clinicians in primary care, urgent care, or EDs. Proper identification and management of these injuries is critical to prevent loss of function, nerve damage, joint instability, persistent pain, or delay in indicated surgery. This article presents case studies of four hand and wrist fractures or dislocations and discusses accurately identifying, stabilizing, and developing follow-up strategies for these injuries.
CASE 1: THUMB PAIN
Two days after a motorcycle accident, a 23-year-old man presented to a primary care office complaining of pain in his left hand at the ulnar aspect of the left thumb along the metacarpophalangeal (MCP) joint.
The patient said he was riding a motorcycle at about 25 mph when he lost control and fell off. His left thumb caught on the handlebar. At the accident scene, he rated his pain as 8 on a 0-to-10 pain intensity rating scale; the pain is now at 2 but increases to 6 when he attempts pinching. He tried ibuprofen and ice with some relief. He has superficial abrasions on his lower extremities but no other injury.
The patient had ecchymosis and mild edema over the ulnar aspect of the MCP joint of his left thumb and a palpable tender mass in the same location. He had pain with range of motion of this joint, most noted with abduction of the thumb. Capillary refill was less than 2 seconds and sensation was intact in the radial and median nerve distribution.
Posterior-anterior and lateral views of the patient's left thumb were obtained and revealed a small avulsion fracture from the ulnar base of the proximal phalanx, with ulnar displacement but no angulation or shortening.
Ulnar collateral ligament injuries of the thumb result from hyperextension abduction forces and typically cause an avulsion of the ligament from the proximal phalanx rather than from the origin of the ligament on the metacarpal. Patients may describe a “popping” sensation and pain at the time of injury.
Sprains of the ulnar collateral ligament have been referred to as skier's thumb and gamekeeper's thumb but these names refer to different mechanisms of ligament injury. Skier's thumb refers to an acute injury in which the thumb is hyperabducted acutely during a fall on an outstretched hand, such as while holding a ski pole handle or falling off a motorcycle. Gamekeeper's thumb refers to a chronic injury resulting from repetitive stress leading to chronic laxity of the ulnar collateral ligament.
During the physical examination, perform a stress test to assess joint laxity and determine the degree of injury. Laxity can be appreciated by applying a valgus force to the thumb. Stress the thumb in a neutral position and then again in flexion. Compare the degree of movement with the uninjured thumb for final assessment. If the joint moves more than 30 degrees, presume an ulnar collateral ligament tear. Using a local anesthetic at the joint site before doing the stress test can decrease pain and yield more accurate examination results.1
Sprains of the ulnar collateral ligament are classified as:
- grade I—pain without laxity
- grade II—partial tear of the ligament with some laxity but with a strong endpoint
- grade III—complete tear of the ligament with laxity and no endpoint.
Stener lesions, irreversible displacements of the ulnar collateral ligament, are a subset of complete tears, and occur when the torn end of the ligament retracts and slips superficially to the leading edge of the adductor pollicis muscle aponeurosis, where it becomes entrapped (Figure 1). These lesions were first described by Bertil Stener in 1962; his case series found this injury in up to 64% of patients with complete ulnar collateral ligament tear.2 Some patients with Stener lesions, such as the case patient, have associated avulsion fractures of the phalanx seen on radiograph; however, an avulsion fracture is not diagnostic of a Stener lesion.
The diagnosis of ulnar collateral ligament tears is made by clinical examination. Radiographs are ordered to detect fractures and joint subluxation. Clinicians also can order a stress radiograph, in which the thumb is gently abducted during the radiograph. Ultrasound has been found useful in some recent studies.3,4 However, ultrasound is less accurate if done more than 2 weeks after initial trauma because ligament retraction and scar tissue formation can hinder the results. An MRI is typically unnecessary unless further needed by the hand surgeon.
Clinicians must identify these injuries and refer patients to hand surgery within 1 week of acute injuries for definitive treatment. Failure to recognize and treat the surgical types of ulnar collateral ligament tears can result in chronic weakness, pain, MCP joint instability, and post-traumatic arthritis.
Sprains and partial tears of the ulnar collateral ligament usually can be managed conservatively with immobilization in a short-arm thumb spica splint or cast for 4 to 6 weeks. Patients may require physical therapy after immobilization due to stiffness. Patients with complete tears or Stener lesions require surgical correction, and should be referred promptly to a hand surgeon once the injury is identified. Surgery also is indicated for patients with a displaced avulsion fracture involving a substantial portion of the joint surface, a grossly unstable joint, symptomatic chronic pain, or volar subluxation on radiograph.5,6 Although these specific types of ulnar ligament tears are not a medical emergency, delaying surgery beyond 6 weeks may complicate the repair of these injuries because of ligament retraction and scarring.
This patient had more than 30 degrees of ulnar collateral ligament laxity during stress testing and an avulsion fracture was identified on radiograph. He was placed in a thumb spica splint and referred to a surgeon within 1 week. Surgical repair of the ulnar collateral ligament took place within 2 weeks of the injury date and the patient was then immobilized for 6 weeks in a removable thumb spica splint. After the splint was removed, he completed a 1-month course of occupational therapy. His grip strength steadily returned to baseline after treatment and he had mild decreased flexion of the left thumb MCP joint when compared with the normal right side. He denied any further pain.
CASE 2: INDEX FINGER PAIN
A 22-year-old woman presented to an ED 30 minutes after falling on her outstretched right hand.
The patient said she was jogging when she tripped over her shoelace and fell. She complained of pain (rating it as a 7), swelling, and deformity of her right index finger. She has no other injuries and denies previous fractures or surgeries in this hand.
The patient had a hyperextension deformity of her right index finger at the MCP joint and no active or passive range of motion of that joint. She had skin dimpling in the proximal right index MCP joint palmar flexion crease but otherwise her skin was intact. The patient noted global hypoesthesia to light touch in the right index finger compared with the left index finger but two-point discrimination was intact at 5 mm. Capillary refill was intact but sluggish at 2 seconds.
Posterior-anterior, oblique, and lateral radiographs of the right index finger were obtained and showed dorsal dislocation of the proximal phalanx on the second metacarpal at the right index MCP joint. No fractures were seen on any views (Figure 2).
Dislocation of the MCP joint is relatively rare due to tendons, muscles, ligaments, and a volar plate that provides this joint with substantial stability. When a dislocation occurs, the direction is defined by the distal bone's position relative to the proximal bone. Dorsal dislocations, rather than volar dislocations, are the most frequent type of dislocation affecting the index finger. Skin dimpling in the proximal palmar crease is a pathognomonic sign for a dorsal dislocation of the MCP joint and an indication that open surgical reduction is necessary.7
The volar plate is a stabilizing soft-tissue structure on the palmar surface of the MCP joint. As the joint is hyperextended, the volar plate can be avulsed from its origin on the distal volar metacarpal (Figure 3). If the force progresses, the volar plate can become incarcerated between the metacarpal and phalanx, leaving the metacarpal head stuck volar to the proximal phalanx. Understanding the pathomechanics of this injury is integral to understanding how to treat it.
These dislocations can be categorized as simple or complex. The treatment differs for each. In a simple dislocation, the volar plate has not been pulled into the joint. In a complex dislocation, the volar plate has been pulled into the joint. Open dislocations, in which a wound occurs near the dislocated joint, are surgical emergencies that require immediate surgical consultation, operative debridement and reduction, antibiotic treatment, and tetanus prophylaxis.
A simple MCP joint dislocation often can be reduced at the bedside with proper technique. Unlike with proximal interphalangeal (PIP) joint reductions, providers must use a special technique to reduce these dislocations. Using traction as in PIP joint dislocations can draw the torn volar plate into the joint, creating a complex dislocation and surgical condition.8 Before reducing an MCP joint dislocation, perform an intra-articular injection of 1% plain lidocaine to provide local anesthesia. Then relax the flexor tendons by placing the patient's wrist and interphalangeal joints in flexion. Place the MCP joint in 90 degrees of hyperextension and while pressing the phalanx against the metacarpal head, apply pressure to the dorsal aspect of the base of the proximal phalanx in an attempt to slide the proximal phalanx and its volar plate over the metacarpal head. Make only one attempt at gentle closed reduction.
This type of reduction typically does not work in complex dislocations because the volar plate has been pulled into the joint, preventing bedside reduction. The tendons and ligaments displace and create a “noose” around the metacarpal neck.
If reduction is unsuccessful, or a complex dislocation or open dislocation is involved, immediately contact a hand surgeon, who should see patients with these surgical emergencies on the same day.
Complications of MCP joint dislocations typically are related to repeated attempts at closed reduction or prolonged dislocation and include early degenerative arthritis, osteonecrosis, and joint stiffness.9
The dimple in the patient's palmar crease noted during physical examination suggested a complex dislocation. A hand surgeon was called for immediate consultation. The patient was taken to the OR for open reduction and placed in an extension block splint for 3 weeks postoperatively. This type of splint prevents redislocation dorsally while allowing full flexion. After 3 weeks of splinting, the patient continued with buddy taping to the middle finger and occupational therapy until range of motion returned to baseline. The patient returned to normal function and grip strength about 3 months postoperatively and was pain-free at the time of discharge from the program.
CASE 3: WRIST PAIN
An 84-year-old woman presented to her primary care provider 1 week after she slipped on a patch of ice and fell on an outstretched left hand.
The patient said her left wrist had been painful since the injury. She describes it as a mild, achy, pain (rating of 4) that increases in intensity to 7 with grasping. She has been using acetaminophen and ice with little relief. She denies any other injuries. She had not yet been evaluated by a provider.
The patient was point tender on the radial aspect of the wrist just proximal to the thumb metacarpal. She had no edema, ecchymosis, abrasions, or lacerations at the wrist or elsewhere on her body. She was capable of dorsal and palmar flexion but had some discomfort with radial deviation. Grip strength was mildly decreased. Pulses were 2+ and capillary refill was less than 2 seconds. Sensation was intact in the radial, ulnar, and median nerve distribution.
Posterior-anterior, lateral, oblique, and scaphoid views of the left wrist were obtained. A transverse mid-waist fracture of the scaphoid was seen, best visualized on the posterior-anterior view, with no comminution, displacement, angulation, or shortening (Figure 4).
Scaphoid fractures are one of the most common types of fracture in the adult upper extremity. Typical mechanisms of injury include an axial load or a fall on the extended wrist. Anatomically, the scaphoid lies in a fossa of the distal radius on the radial aspect of the wrist. The blood supply enters the scaphoid distally, which makes this carpal bone at risk for compromised fracture healing. Higher energy injuries lead to greater risk of nonunion and avascular necrosis. Fracture displacement, comminution, and more proximal fracture location increase the probability of these complications. Patients often present with a paucity of findings on physical examination. They may have limited or no edema and range of motion may only be slightly affected. The most common clue to injury usually is point tenderness in the anatomic snuffbox (the soft-tissue area bordered by the extensor pollicis longus, extensor pollicis brevis, and abductor pollicis longus). This area can be found by placing the thumb in extension while the wrist is in neutral position, causing the tendons to become more prominent.
If scaphoid fracture is suspected, order radiographs including a posterior-anterior, lateral, oblique, and scaphoid view of the wrist. However, even with the appropriate radiographs, scaphoid fractures can be difficult to detect. One study found a 20% occurrence of false-negative radiographs.10 MRI, CT scan, and/or bone scan are secondary, more sensitive studies that can demonstrate the diagnosis but should be left to the discretion of the hand surgeon. In addition to looking for a fracture, scrutinize the radiographs for signs of scapholunate ligament dissociation with widened space between the scaphoid and the lunate, volar flexion of the scaphoid, and/or dorsiflexion of the lunate relative to the opposite wrist.
Patients with suspected scaphoid fracture should have their wrist immobilized in a forearm-based thumb spica splint in the acute care setting. Obtain an emergent surgical consult for patients with open fractures or those with neurovascular compromise. Refer patients to a hand surgeon within several days for any identified or suspected scaphoid fracture, associated scapholunate ligament rupture, or suspected carpal instability. Complications include nonunion, avascular necrosis, intractable pain, stiffness, and wrist instability.
This patient had a nondisplaced transverse scaphoid fracture in the middle third of the scaphoid bone. She was initially placed in a forearm-based thumb spica splint and referred to a hand surgeon within 3 days for further evaluation. She remained immobilized in a short arm thumb spica cast for 16 weeks, followed with serial radiographs that ultimately confirmed bone union. She then completed a course of occupational therapy. She returned to normal range of motion, strength, and function at the completion of treatment and was pain-free upon discharge from the program.
CASE 4: WRIST PAIN
A 53-year-old man presented to an urgent care center after falling off a horse.
The patient said he was part of a steeplechase and was galloping at full speed when the horse refused to jump an obstacle. The patient was abruptly thrown from the horse due to the sudden deceleration. He described dorsiflexion of his right wrist on landing. He notes mild abrasions on his lower extremities but denies any other injuries.
He had moderate ecchymosis, edema, and diffuse tenderness in his right wrist with decreased range of motion and a visible deformity. Radial pulse was intact. He had prolonged capillary refill time and decreased two-point sensation in the median nerve distribution.
Posterior-anterior and lateral radiographs of the right wrist were obtained and showed a disruption in Gilula lines, the smooth lines joining the edges of the carpal bones (Figure 5). The “piece of pie” sign was present where the lunate overlapped the capitate and took on a triangular shape (Figure 5). The lateral view revealed the classic “spilled tea cup” sign in which the lunate remains in normal position and the capitate is dislocated posteriorly (Figure 6).
Perilunate dislocations and fracture dislocations are a rare type of orthopedic injury. Even when diagnosed and treated expediently, they are among the most potentially devastating closed injuries of the wrist. Research has shown that up to 25% of these injuries are missed upon initial presentation, often resulting in disabling conditions.11 Patients typically present after falling on an outstretched hand from a significant height or with significant force. Upon landing, the wrist usually is in a hyperextended and ulnar-deviated position.
Perilunate and lunate dislocations frequently are confused. In perilunate dislocations, the capitate and other carpal bones are dislocated posteriorly relative to the lunate, which remains in normal alignment. In a lunate dislocation, the lunate itself dislocates out of the lunate fossa (typically anteriorly) and the other carpal bones stay in their anatomic position.
Although plain radiographs usually are sufficient to make the diagnosis, perilunate and lunate dislocations often are missed in acute care. A CT scan can assess for associated fractures, including scaphoid fractures. An MRI can assess for ligamentous tears or occult fractures if needed for further evaluation; however, MRI is not considered a first-line test and these cases should be discussed with the hand surgeon before ordering this study.
Perilunate and lunate dislocations typically are associated with high-energy mechanisms of injury. If left unreduced, they can disrupt the vascular supply to the lunate, making these injuries a medical emergency. Restoring carpal anatomy quickly is important to minimize the risk of avascular necrosis of the lunate. Patients with these injuries need to be seen by a hand surgeon immediately.
Initial treatment for perilunate dislocation is closed reduction and stabilization by a hand surgeon. If closed reduction is unsuccessful, emergent open reduction and internal fixation is performed, followed by immobilization in a splint or cast.
Long-term complications can include median nerve palsy, avascular necrosis, compartment syndrome, arterial compromise, complex regional pain syndrome, and chronic carpal instability; even with appropriate treatment, long-term risk of degenerative arthritis is high (56%).11
The patient was placed in a volar splint and immediately transferred to the local ED, where a hand surgeon was consulted. Treatment consisted of open reduction and internal fixation the same day. The patient was placed in a splint for 10 days, which was then converted to a short arm cast for 8 weeks. After the cast was removed, he completed a course of occupational therapy over 6 months. He had serial radiographs every 6 months for 18 months. Despite appropriate treatment, the patient had decreased range of motion in the wrist, decreased grip strength, and persistent pain with exertion at the 3-year follow-up.
Accurate and prompt diagnosis of hand and wrist injuries through a high level of suspicion, careful physical examination, and critical analysis of radiographs is imperative. Once the injury is identified, administer proper temporary care and refer patients to a hand surgeon for optimal care and to prevent complications.