Medial Collateral Ligament of the Elbow

Original Editor - Rania Nasr Top Contributors - Rania Nasr, Amanda Ager and Kim Jackson

Top Contributors - Rania Nasr, Amanda Ager and Kim Jackson

Description

The elbow joint is one of the most congruent of the human body; as it is a ginglymus (hinge) joint it affords rotational stability in the sagittal plane and in varus and valgus motion. It is used extensively in various daily activities and constantly receives medial overloads, particularly when in extension. This overload can lead to acute or chronic injuries. The major elbow stabilizers are the medial and lateral collateral ligaments and the ulnohumeral joint.

Attachments

The medial collateral ligament originates from the anterior inferior surface of the medial epicondyle and joins the ulna to the humerus, providing support and resistance in valgus overloads. This ligament is divided into an anterior band, which is stressed during the elbow extension movement; a posterior band, which is stressed during elbow flexion; and a transverse band, which joins the anterior and posterior bands.

Vascular supply

Generally, the vascular supply to the proximal elbow joint - ulnar collateral artery, radial collateral artery, middle collateral artery. While the distal part of the elbow is supplied by - radial recurrent artery, ulnar recurrent artery. However, the vascular supply of the ulnar collateral ligament (UCL) is unknown. A recent study found a difference in the vascular supply of the UCL. The proximal UCL was well vascularized, while the distal UCL was hypovascular. This difference in vascular supply may be a factor in the differential healing capacities of the UCL based on the location of injury.

Nerve supply

Ulnar collateral ligament is innervated by branches of the radial, ulnar and medial nerves in the elbow joint, and a close relationship was observed in a study between their capsular and motor branches.

Function

The anterior band is the only structure of the MCL whose isolated sectioning allows the valgus opening of the elbow, acting as the main elbow stabilizer in valgus instability. When the posterior band is sectioned separately or in association with the sectioning of the articular capsule, keeping the anterior band intact, valgus opening of the elbow does not occur. In the interval from 50° to 70° of elbow flexion there is maximum valgus opening when the anterior band, articular capsule and posterior band of the MLC are sectioned.

Clinical relevance

The MUCL is commonly injured in overhead throwing athletes, such as pitchers, javelin throwers, quarterbacks, tennis, volleyball, and water polo players, when a valgus moment is placed on the elbow during the late cocking and early acceleration phases. Incompetence or rupture of the ligament leads to valgus instability which has varying clinical presentations. Patients may complain of instability, however, most will report pain, reduced accuracy, and decreased velocity. Clinically significant pathology often requires surgical intervention.

Assessment

A UCL tear can be diagnosed through a history and physical examination. A valgus stress test, during which a physician tests your elbow for instability, is the best way to assess the condition of the UCL.

Treatment

Damage to the medial collateral ligament of the elbow from an instability episode usually heals with non-operative treatment. In some cases, residual instability may occur, leading to functional impairment. Non-operative management can be successful when bracing, taping and therapy are used to stabilise the elbow. A recent report detailing the efficacy of platelet-rich plasma in effectively treating ulnar collateral ligament (UCL) injuries in throwers has shown promise. However, there remain specific groups that should be considered for repair or reconstruction. These may include throwing athletes, wrestlers and some individuals involved in highly active physical activity which demands stability of the elbow. The results of surgical repair and reconstruction allowing a return to sports are quite good, ranging from 84% to 94%. Complications are generally low and mostly centered on ulnar nerve injuries.

Rehabilitation program following ulnar collateral ligament reconstruction using the docking procedure:

Postoperative Phase 1: Weeks 1-4

Goals:

• Promote healing: reduce pain, inflammation, and swelling
• Begin to restore range of motion to 30-90°
• Independent home exercise program.

Precautions:

• Brace should be worn at all times
• No passive range of motion of the elbow

Treatment strategies:

• Brace set at 30° to 90° of flexion
• Elbow, active range of motion in brace
• Wrist, active range of motion
• Scapula isometrics
• Gripping exercises
• Cryotherapy
• Home exercise program

Criteria for advancement:

• Elbow, range of motion: 30°-90°
• Minimal pain or swelling

Postoperative Phase 2: Weeks 4-6

Goals:

• Range of motion: 15°-115°
• Minimal pain and swelling

Precautions:

• Continue to wear brace at all times
• Avoid passive range of motion
• Avoid valgus stress

Treatment strategies:

• Continue active range of motion in brace
• Begin pain-free isometrics in brace (deltoid, wrist flexion/extension, elbow flexion/extension)
• Manual scapula stabilization exercises with proximal resistance
• Modalities as needed
• Modify home exercise program

Criteria for advancement:

• Range of motion: 15°-115°
• Minimal pain and swelling

Postoperative Phase 3: Weeks 6-12

Goals:

• • Restore full range of motion
  • All upper extremity strength: 5/5
  • Begin to restore upper extremity endurance

Precautions:

• Minimize valgus stress
• Avoid passive range of motion by the clinician
• Avoid pain with therapeutic exercise

Treatment strategies:

• Continue active range of motion
• Low-intensity/long-duration stretch for extension
• Isotonics for scapula, shoulder, elbow, forearm, wrist
• Begin internal/external rotation strengthening at 8 weeks
• Begin forearm pronation/supination strengthening at 8 weeks
• Upper body ergometer (if adequate range of motion)
• Neuromuscular drills
• Proprioceptive neuromuscular facilitation patterns when strength is adequate
• Incorporate eccentric training when strength is adequate
• Modalities as needed
• Modify home exercise program

Criteria for advancement:

• Pain-free
• Full elbow range of motion
• All upper extremity strength 5/5

Postoperative Phase 4: Weeks 12-16

Goals:

• Restore full strength and flexibility
• Restore normal neuromuscular function
• Prepare for return to activity

Precautions:

• Pain-free plyometrics

Treatment strategies:

• Advance internal/external to 90/90 position
• Full upper extremity flexibility program
• Neuromuscular drills
• Plyometric program
• Continue endurance training
• Address trunk and lower extremities
• Modify home exercise program

Criteria for advancement:

• Complete plyometrics program without symptoms
• Normal upper extremity flexibility

Postoperative Phase 5: Months 4-9

Goals:

• Return to activity
• Prevent reinjury

Precautions:

• Significant pain with throwing or hitting
• Avoid loss of strength or flexibility

Treatment strategies:

• Begin interval throwing program at 4 months
• Begin hitting program at 5 months
• Continue flexibility exercises
• Continue strengthening program (incorporate training principles)

Criteria for discharge:

• Pain-free
• Independent home exercise program
• Independent throwing/hitting program

Resource

Elbow Join

Ulnar Collateral Ligament (UCL) Injuries of the Elbow