eMedicine Specialties > Sports Medicine > Upper Limb

Ulnar Collateral Ligament Injury

Robert F Kacprowicz, MD, Program Director, San Antonio Uniformed Services Health Education Consortium Residency in Emergency Medicine
Eric Chumbley, MD, Consulting Staff, Department of Sports Medicine, Trover Clinic

Updated: Sep 26, 2007

Introduction

Background

The ulnar collateral ligament (UCL) of the elbow is critical for valgus stability of the elbow and is the primary elbow stabilizer.^1,2 As such, the UCL plays an important role in most throwing sports, including baseball and javelin, as well as racquet sports and ice hockey.

Elbow injuries in young athletes are generally chronic, with persistent pain and instability from repetitive overhead activities. In the athlete, ligamentous injury can also be heralded by an acute traumatic event such as an elbow dislocation. This can then lead to chronic pain and valgus instability. An understanding of the anatomy and biomechanics of the elbow in throwing sports is essential to the correct diagnosis and treatment of this potentially disabling injury.³

Functional Anatomy

The UCL originates at the posterior distal aspect of the medial epicondyle and inserts into the base of the coronoid process. At 90 º of flexion, it provides 55% of the resistance to valgus stress at the elbow. In full extension, the UCL, bony architecture, and anterior capsule equally maintain valgus stability.

The UCL is composed of 3 bands: anterior, posterior, and transverse. The anterior band, which arises from the anteroinferior surface of the medial epicondyle and inserts on the sublime tubercle of the ulna, provides the major contribution to valgus stability.

Sport-Specific Biomechanics

The acceleration phase of the overhead throw causes the greatest amount of valgus stress to the elbow.⁴ Extension occurs at a rate of up to 2500 º per second and continues to 20 º of flexion. During this phase, the forearm lags behind the upper arm and generates valgus stress while the elbow is primarily dependent on the anterior band of the UCL for stability. During the acceleration phase, valgus stress can exceed 60 Newton meters (Nm), which is significantly higher than the measured strength of the UCL in cadavers. The valgus force can, therefore, overcome the tensile strength of the UCL and cause either chronic microscopic tears or acute rupture.

Clinical

History

• Medial elbow pain is the most common symptom in athletes who throw. Pain may be especially prominent during the acceleration phase of the overhead throw.
• Pain is often chronic or recurrent, and it may lead to a slow erosion of the patient's throwing ability.
• Athletes may report having had similar pain in previous seasons of throwing.
• Rest generally helps to relieve the pain.
• Occasionally, during a single throw, athletes may experience acute pain over the medial elbow, sometimes associated with a popping sensation, that causes them to immediately stop throwing.

Physical

• Medial elbow tenderness and swelling are the most notable findings. Tenderness is commonly found approximately 2 cm distal to the medial epicondyle. UCL tenderness may occasionally be difficult to differentiate from flexor pronator tendinitis, but the pain of flexor pronator tendinitis is aggravated by resisting forearm pronation.
• Loss of elbow range of motion (ROM) is occasionally observed.
• With acute rupture, ecchymosis may be observed over the medial elbow.
• Pain may be reproduced when the patient makes a clenched fist.
• Valgus stress with the elbow in 25° of flexion (elbow abduction stress test) reproduces pain and may cause joint opening. The affected side should be compared with the contralateral elbow as a reference for baseline laxity.
• Some throwing athletes have a baseline asymmetry; therefore, preseason documentation of baseline elbow laxity in elite athletes, especially pitchers, may be helpful for comparison if an injury occurs during the season.

Causes

• Repetitive throwing motions are the most common cause of UCL injury in the athlete.
• Traumatic valgus stress to the elbow during a fall or with the arm outstretched may lead to UCL rupture in association with elbow dislocation.

Differential Diagnoses

Elbow and Forearm Overuse Injuries
Little League Elbow Syndrome
Medial Condylar Fracture of the Elbow
Medial Epicondylitis

Other Problems to Be Considered

Flexor pronator muscle tear/tendinitis
Ulnar neuritis/ulnar nerve entrapment
Medial epicondylar fracture
Valgus extension overload

Workup

Laboratory Studies

• Laboratory studies are not indicated during the workup of UCL injuries.

Imaging Studies

• Radiography
  • Findings from routine radiography can occasionally be diagnostic if an avulsion fragment is seen, and in a minority of patients, this study can also reveal secondary findings that are suggestive of UCL injury, such as ossification of the ligament. Plain radiographs are also helpful to rule out other causes of elbow pain, such as epitrochlear osteophytes, epicondylar fractures, posterior olecranon fossa loose bodies, ligamentous calcification, or capitellar lesions.⁵
  • Manual or instrumented valgus stress radiography can be used to document increased joint opening and ligamentous laxity. Significant asymmetry may be observed in traumatic elbow injuries such as dislocations, whereas laxity in a throwing athlete may not be so obvious, with only a very subtle asymmetry.
  • Gravity stress radiography — with the patient supine, the shoulder in maximal external rotation, and the weight of the forearm resisted by the UCL — may also be helpful.⁶
• Plain arthrography: This imaging modality is not indicated because dye leak has been shown to be inconsistent in cases of chronic laxity, and only an acute event may be anticipated to exhibit a positive finding.
• Magnetic resonance imaging (MRI): MRI with contrast, as with all soft-tissue injuries, is rapidly becoming the imaging study of choice to document ligamentous rupture; however, because of the relatively small size of the UCL and the failure of dye leakage in chronic injury,⁷ even MRI may generate false-negative results.
• Dynamic ultrasonography: This modality may be helpful in the evaluation of ligamentous laxity in throwing athletes; however, studies of this modality for acute injuries are lacking.⁸
• Computed tomography scanning (CT) with intra-articular contrast: This technique has been studied in small numbers of patients. CT scanning with intra-articular contrast appears to be highly sensitive and specific for both acute and chronic injuries,⁷ but more data are needed before widespread use can be recommended.

Procedures

• Arthroscopy is believed by some authors to be the most specific diagnostic procedure because it allows visualization of the medial compartment while valgus stress is applied; however, clinical suspicion of a UCL injury via a good history and physical examination is probably the most reliable in making the diagnosis.

Treatment

Acute Phase

Rehabilitation Program

Physical Therapy

Generally, 3-6 months of conservative therapy with rest, nonsteroidal anti-inflammatory drugs (NSAIDs), and local physical therapy for ROM are necessary for recovery.

Recreational Therapy

When pain and swelling completely resolve and the athlete has returned to a premorbid ROM (usually not before 3 months of treatment), progressive return to activity with increasing velocity and duration of training may be attempted.

Medical Issues/Complications

Surgery may be considered in several situations. Surgical repair is generally indicated for acute tears in competitive athletes, when chronic instability exists, and when the patient has recurring pain and laxity after 2 or more attempts at conservative therapy.

Surgical Intervention

Direct repair of the ligament is generally not indicated. Reconstruction of the UCL (eg, repair of the anterior bundle) is the more common approach to surgical treatment, with use of a palmaris longus tendon autograft. The graft is pulled through bone tunnels in the medial epicondyle of the humerus and the sublime tubercle of the ulna in a figure-8 pattern. Ulnar nerve transposition may be undertaken at the time of surgery, if indicated.

Consultations

Consultation with an orthopedic surgeon, preferably a sports or upper-extremity specialist, is indicated when surgical intervention is contemplated.

Other Treatment

Steroid injection is not recommended for UCL injuries.

Recovery Phase

Rehabilitation Program

Physical Therapy

After surgery, the elbow is immobilized in a posterior splint for 10 days in 90° of flexion. The wrist is maintained free, and a soft rubber ball is given to the patient for squeezing to maintain grip strength. Active ROM is initiated after removal of the posterior splint. A hinged brace that prevents valgus stress should be used.

At approximately 1 month after surgery, isometric strengthening exercises should be initiated. Limited progressive strengthening can be initiated at 8 weeks and plyometrics at 12 weeks. Shoulder and elbow exercises should be instituted as soon as feasible, but valgus stress of the elbow should be avoided for at least 4-6 months until the graft has had sufficient time to incorporate.

Recreational Therapy

After 4-6 months, throwing may be resumed with a training program that is designed to return the patient to competitive throwing by 9-12 months after surgery.

Medical Issues/Complications

Both transient and permanent ulnar neuropathy may occur after reconstruction, occasionally requiring ulnar nerve transposition or revision of transposition. Flexion contracture (generally <5°) may also occur in 25-30% of patients.

Surgical Intervention

Ulnar nerve transposition (or revision of transposition) may be required for persistent postoperative ulnar neuropathy.

Maintenance Phase

Rehabilitation Program

Physical Therapy

Flexibility and strength training of the elbow are useful in the maintenance phase to prevent recurrent injury.

Recreational Therapy

During the maintenance phase, particular attention to the patient's throwing technique is essential to prevent recurrence of injury.

Medical Issues/Complications

Long-term complications may include chronic pain with throwing and chronic instability of the elbow.

Medication

NSAIDs are the cornerstone of therapy for the control of pain that is associated with UCL injuries.

Analgesics

Pain control is essential to patient care.

Ibuprofen (Ibuprin, Motrin, Advil)

DOC for treating mild to moderate pain if no contraindications exist. Inhibits inflammatory reactions and pain by decreasing the activity of the enzyme COX and thereby inhibiting production of prostaglandins.

Dosing

Adult

400 mg PO q4-6h, 600 mg q6h, or 800 mg q8h PO while symptoms persist; not to exceed 3.2 g/d

Pediatric

<6 months: Not established
6 months to 12 years: 20-40 mg/kg/d PO divided tid/qid
>12 years: Administer as in adults

Interactions

Probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; ibuprofen may decrease the effect of loop diuretics; PT duration may increase when ibuprofen is administered with anticoagulants; monitor PT and observe for bleeding; ibuprofen and other NSAIDs may increase serum lithium levels and the risk of methotrexate toxicity

Contraindications

Documented hypersensitivity; aspirin-, iodide-, or other NSAID-induced hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency; high risk of bleeding

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Use with caution in patients with congestive heart failure, hypertension, and decreased renal and hepatic function.

Acetaminophen (Tylenol, Feverall, Aspirin Free Anacin, Tempra)

DOC for treating mild pain in patients with documented hypersensitivity to aspirin or NSAIDs, those diagnosed with upper GI disease, or those who take PO anticoagulants.

Dosing

Adult

325-650 mg PO q4-6h or 1000 mg tid/qid; not to exceed 4 g/d
Alternative, 1000 mg tid/qid; not to exceed 4 g/d

Pediatric

<12 years: 10-15 mg/kg/dose PO q4-6h prn; not to exceed 2.6 g/d
>12 years: 325-650 mg PO q4h; not to exceed 5 doses/d

Interactions

Rifampin can reduce the analgesic effects of APAP; barbiturates, carbamazepine, hydantoins, and isoniazid may increase liver toxicity.

Contraindications

Documented hypersensitivity; G6PD deficiency

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

Precautions

Hepatotoxicity can occur in patients with long-term alcoholism.

Naproxen (Naprosyn, Anaprox, Naprelan)

Used for relief of mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing the activity of the enzyme COX and thereby inhibiting production of prostaglandins.

Dosing

Adult

500 mg PO followed by 250 mg q6-8h; not to exceed 1.25 g/d; may increase to 1.5 g/d for limited periods

Pediatric

<2 years: Not established
>2 years: 2.5 mg/kg/dose PO; not to exceed 10 mg/kg/d

Interactions

Probenecid and lithium may increase the concentrations and, possibly, the toxicity of NSAIDs; effect of loop diuretics may decrease when coadministered with this drug; PT duration may increase when naproxen is coadministered with anticoagulants; monitor PT and watch for bleeding; coadministration with phenytoin may increase serum phenytoin levels, resulting in an increase in the pharmacologic and toxic effects of phenytoin

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, hyperkalemia, hyponatremia, interstitial nephritis, and renal papillary necrosis may occur; increases risk of acute renal failure in patients with preexisting renal disease or compromised renal perfusion; low WBC counts (rare) usually return to the reference range in ongoing therapy; discontinuing therapy may be necessary if persistent leukopenia, granulocytopenia, or thrombocytopenia occurs; perform ophthalmologic studies in patients who develop eye symptoms during therapy; discontinue therapy if changes are noted; changes may include blurred or diminished vision, corneal deposits and retinal disturbances, scotomata, changes in color vision, and macular degeneration

Ketoprofen (Oruvail, Orudis, Actron)

Used to relieve mild to moderate pain and inflammation. Initially administer small dosages to patients with a small body size, elderly patients, and those with renal or liver disease. Doses >75 mg do not increase therapeutic effects. Administer high doses with caution, and closely observe patients for response.

Dosing

Adult

25-50 mg PO q6-8h prn; not to exceed 300 mg/d

Pediatric

<3 months: Not established
3 months to 12 years: 0.1-1 mg/kg PO q6-8h
>12 years: Administer as in adults

Interactions

Probenecid and lithium may increase the concentrations and, possibly, the toxicity of NSAIDs; effect of loop diuretics may decrease when coadministered; PT duration may increase when ketoprofen is coadministered with anticoagulants; monitor PT closely and watch for bleeding; coadministration with phenytoin may increase serum phenytoin levels, resulting in an increase in the pharmacologic and toxic effects of phenytoin

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Avoid use in patients diagnosed with GI disease, cardiovascular disease, or renal or hepatic impairment and in patients receiving anticoagulants.

Acetaminophen and codeine (Tylenol with codeine #3)

Drug combination indicated for treatment of mild to moderate pain.

Dosing

Adult

Based on codeine dose: 30-60 mg/dose PO q4-6h or 1-2 tab PO q4h; not to exceed 12 tabs/d

Pediatric

Based on codeine dose: 0.5-1 mg/kg/dose PO
Based on acetaminophen dose: 10-15 mg/kg/dose PO q4h; not to exceed 2.6 g/d of acetaminophen

Interactions

Toxicity increases when coadministered with CNS depressants or tricyclic antidepressants

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Administer with caution in patients who are dependent on opiates because this substitution may result in acute opiate withdrawal symptoms; exercise caution when patients have severe renal or hepatic dysfunction.

Oxycodone and acetaminophen (Percocet)

Drug combination indicated to relieve moderate to severe pain. DOC for aspirin-hypersensitive patients.

Dosing

Adult

1-2 tab or cap PO q4-6h prn

Pediatric

0.05-0.15 mg/kg/dose of oxycodone PO; not to exceed 5 mg/dose of oxycodone PO q4-6h prn

Interactions

Phenothiazines may decrease analgesic effects of this medication; toxicity increases with coadministration of either CNS depressants or tricyclic antidepressants

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Safety for use during pregnancy has not been established.

Precautions

Duration of action may increase in elderly patients; be aware of the patient's total daily dose of acetaminophen; doses higher than the maximum (4000 mg/d) may cause liver toxicity

Hydrocodone bitartrate and acetaminophen (Vicodin, Lortab, Norcet)

Drug combination indicated to relieve moderate to severe pain.

Dosing

Adult

1-2 tab or cap PO q4-6h prn

Pediatric

<12 years: 10-15 mg/kg/dose acetaminophen PO q4-6h prn; not to exceed 2.6 g/d of acetaminophen or 5 mg of hydrocodone bitartrate per dose
>12 years: 650 mg acetaminophen PO q4h; not to exceed 4 g/d acetaminophen or 10 mg of hydrocodone bitartrate per dose

Interactions

Phenothiazines may decrease analgesic effects; toxicity of this drug increases when coadministered with CNS depressants or tricyclic antidepressants

Contraindications

Documented hypersensitivity; elevated intracranial pressure

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Tabs contain metabisulfite, which may cause allergic reactions; administer with caution in patients who are dependent on opiates because this substitution may result in acute opiate withdrawal symptoms; exercise caution when patients have severe renal or hepatic dysfunction.

Follow-up

Return to Play

Competition may be resumed when the following criteria are met:

• The athlete is pain free with throwing.
• Elbow and shoulder ROM has returned to within normal limits.
• Forearm strength has returned to baseline.
• Good throwing biomechanics have been established.

Complications

• Ulnar nerve injury or entrapment may occur.
• Chronic instability is possible.

Prevention

Injuries to the UCL are best prevented by ensuring proper throwing biomechanics. Coaches are essential to assessing the proper throwing techniques in the athlete. Thorough warm-up and flexibility exercises also play an essential role in preventing UCL injuries.

Prognosis

Return to competitive throwing by the patient is possible after successful rehabilitation and reconstruction, when indicated.

Education

Proper throwing technique is essential to preventing UCL injuries; therefore, athlete education is critical. Analysis of the athlete's throwing technique and constructive criticism by coaches may be helpful.

Miscellaneous

Medicolegal Pitfalls

• Failure to consider UCL injury despite negative radiographic findings
• Failure to refer patients with suspected complete UCL tears

Special Concerns

• Pediatric patients, because of immaturity of their elbows, may experience an avulsion injury of the medial epicondyle due to tensile loads of the valgus elbow. The lateral elbow undergoes corresponding compressive loads that could result in problems such as osteochondritis dissecans or Panner disease of the capitellum.

References

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2. Lee ML, Rosenwasser MP. Chronic elbow instability. Orthop Clin North Am. Jan 1999;30(1):81-9. [Medline].

3. Maloney MD, Mohr KJ, el Attrache NS. Elbow injuries in the throwing athlete. Difficult diagnoses and surgical complications. Clin Sports Med. Oct 1999;18(4):795-809. [Medline].

4. Fleisig GS, Andrews JR, Dillman CJ, Escamilla RF. Kinetics of baseball pitching with implications about injury mechanisms. Am J Sports Med. Mar-Apr 1995;23(2):233-9. [Medline].

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7. Timmerman LA, Schwartz ML, Andrews JR. Preoperative evaluation of the ulnar collateral ligament by magnetic resonance imaging and computed tomography arthrography. Evaluation in 25 baseball players with surgical confirmation. Am J Sports Med. Jan-Feb 1994;22(1):26-31; discussion 32. [Medline].

8. Sasaki J, Takahara M, Ogino T, et al. Ultrasonographic assessment of the ulnar collateral ligament and medial elbow laxity in college baseball players. J Bone Joint Surg Am. Apr 2002;84-A(4):525-31. [Medline].

9. Curl LA. Return to sport following elbow surgery. Clin Sports Med. Jul 2004;23(3):353-66, viii. [Medline].

10. Darlis NA, Kaufmann RW, Sotereanos DG. Open surgical treatment of post-traumatic elbow contractures in adolescent patients. J Shoulder Elbow Surg. Nov-Dec 2006;15(6):709-15. [Medline].

11. Dines JS, Elattrache NS, Conway JE, Smith W, Ahmad CS. Clinical outcomes of the DANE TJ technique to treat ulnar collateral ligament insufficiency of the elbow. Am J Sports Med. Aug 16 2007;epub ahead of print. [Medline].

12. Gibson BW, Webner D, Huffman GR, Sennett BJ. Ulnar collateral ligament reconstruction in major league baseball pitchers. Am J Sports Med. Apr 2007;35(4):575-81. [Medline].

13. Grana WA, Boscardin JB, Schneider HJ, et al. Evaluation of elbow and shoulder problems in professional baseball pitchers. Am J Orthop. Jun 2007;36(6):308-13. [Medline].

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Keywords

medial collateral ligament injury, little leaguer's elbow, UCL injury, elbow injury/trauma, elbow pain, valgus elbow instability

Contributor Information and Disclosures

Author

Robert F Kacprowicz, MD, Program Director, San Antonio Uniformed Services Health Education Consortium Residency in Emergency Medicine
Robert F Kacprowicz, MD is a member of the following medical societies: American Academy of Emergency Medicine and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Coauthor(s)

Eric Chumbley, MD, Consulting Staff, Department of Sports Medicine, Trover Clinic
Eric Chumbley, MD is a member of the following medical societies: American Academy of Family Physicians, American College of Sports Medicine, and Uniformed Services Academy of Family Physicians
Disclosure: Nothing to disclose.

Medical Editor

Craig C Young, MD, Associate Professor, Departments of Orthopedic Surgery and Community and Family Medicine, Medical Director of Sports Medicine, Sports Medicine Fellowship Director, Medical College of Wisconsin
Craig C Young, MD is a member of the following medical societies: American Academy of Family Physicians, American College of Sports Medicine, American Medical Society for Sports Medicine, Phi Beta Kappa, and Wilderness Medical Society
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Henry T Goitz, MD, Chief, Sports Medicine, Associate Professor, Department of Orthopaedic Surgery, Medical College of Ohio
Henry T Goitz, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons and American Orthopaedic Society for Sports Medicine
Disclosure: Nothing to disclose.

CME Editor

Jon B Whitehurst, MD, Clinical Instructor of Surgery, University of Illinois College of Medicine; Partner and Executive Board Member, Rockford Orthopedic Associates; Orthopedic Chairman, Rockford Memorial Hospital
Jon B Whitehurst, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American Orthopaedic Society for Sports Medicine, and Arthroscopy Association of North America
Disclosure: Nothing to disclose.

Chief Editor

Sherwin SW Ho, MD, Associate Professor, Department of Surgery, Section of Orthopedic Surgery and Rehabilitation Medicine, University of Chicago
Sherwin SW Ho, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American Orthopaedic Society for Sports Medicine, and Arthroscopy Association of North America
Disclosure: Nothing to disclose.

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