Medial Epicondylitis

Etiology

Medial epicondylitis, commonly known as golfer's or tennis elbow, primarily results from repetitive strain caused by activities involving frequent gripping under load, forearm pronation, and wrist flexion. This condition is prevalent in athletes such as baseball pitchers, javelin throwers, golfers, tennis players, bowlers, rock climbers, archers, and weightlifters, with the highest occurrence rates observed in golfers, tennis players, and pitchers.[6][7] The condition typically arises from intense valgus stress during critical throwing or golf swing phases, especially just before and during the ball or ground contact. Although it is often linked with sports, medial epicondylitis also affects the general population, including carpenters, utility workers, butchers, and caterers. Poor body mechanics, improper techniques, or inadequate equipment frequently often contribute to the onset of this condition.[8]

Epidemiology

Epicondylitis is a common arm disorder, with medial epicondylitis being significantly less prevalent compared to lateral epicondylitis, which is about 7 to 10 times less frequent.[1] Medial epicondylitis accounts for approximately 10% of all epicondylitis cases.[9] According to a Finnish study involving 4,783 participants, the prevalence of medial epicondylitis was 0.4%.[10] In the United States military, the incidence rate was 5.6 per 1000 person-years.[9] This condition more often affects females compared to males and predominantly occurs in middle-aged individuals, especially in their 40s and 50s.

Typically, the symptoms manifest in the patient's dominant arm, reflecting the condition's etiology.[8] Risk factors associated with developing medial epicondylitis include smoking, diabetes, obesity, and engaging in activities requiring repetitive wrist flexion or forearm pronation for 2 or more hours daily.[11][12] Most patients experience a self-limiting course of the condition, with about 80% recovering within 1 to 3 years.[5]

Pathophysiology

Epicondylitis is predominantly regarded as a chronic tendinosis rather than an acute inflammation. This condition involves degenerative changes from overuse and is characterized by findings such as angiofibroblastic hyperplasia or tendinosis.[13] Nirshel has outlined 4 stages in the progression of epicondylar tendinosis as follows:

• Generalized inflammation
• Angiofibroblastic degeneration
• Structural failure
• Fibrosis and calcification

These stages highlight a pattern of repetitive micro-tearing at the tendon's origin, accompanied by an unsuccessful healing process.[3] The pronator teres and flexor carpi radialis tendons are most frequently involved, although research suggests that all flexor tendons could be equally affected. While chronic repetitive microtrauma is often cited as the cause, epicondylitis can also result from acute trauma due to a sudden muscle contraction.[8]

Histopathology

Several studies have detailed the histopathological changes observed in lateral epicondylitis, with fewer studies examining medial epicondylitis. Nonetheless, it is recognized that both conditions share a similar chronic degenerative process.[8][12] The histological features observed include:

• Hypertrophic immature fibroblasts
• Disorganized collagen
• Vascular hyperplasia
• Absence of inflammatory cells

These characteristics of chronic degeneration and unsuccessful healing are believed to result from repetitive microtrauma coupled with the tendons' poor blood supply.

History and Physical

Patients typically present with pain in the medial aspect of the elbow, exacerbated with activities such as gripping, throwing, and forearm flexion/pronation. This pain generally subsides with rest. Although it often develops gradually, it can also appear suddenly following trauma or injury.[12] Some individuals may experience radiating pain into the forearm or wrist, and chronic cases might exhibit reduced grip strength.[11] Morning exacerbation of pain is common. Obtaining a detailed social history focusing on occupations and hobbies involving repetitive elbow bending, wrist flexion, and twisting is crucial to identifying potential causes. Patients often report associated numbness in the distribution of the ulnar nerve in the hand due to the ulnar nerve's anatomical location posterior to the medial epicondyle within the cubital tunnel.[8]

The elbow's appearance, such as swelling or redness, varies depending on the rapidity of pain onset but is typically unremarkable in long-standing cases. Tenderness to palpation is most notable 5 to 10 mm distal to the medial epicondyle at the insertion of the flexor-pronator mass.[14] The pain is generally aggravated by resisted wrist flexion and pronation, with the latter being the most sensitive examination finding.[15] During testing, the elbow should be flexed at 90° to isolate the pronator teres.[5] Flexion contracture could be a late finding in an untreated case of medial epicondylitis.[8] As ulnar neuritis can occur simultaneously in patients with medial epicondylitis, a careful neurological examination should be performed. This examination should include sensory and motor testing of the hand and wrist, assessment of Tinel's sign at the medial elbow within the cubital tunnel, and evaluation for subluxation of the ulnar nerve out of the ulnar groove.[16] In addition, the milking maneuver and valgus stress test should be performed to assess ulnar collateral ligament stability.

Evaluation

Diagnosis of medial epicondylitis is typically established through clinical history and physical examination, rendering further diagnostic investigation unnecessary in many cases.[6] However, in scenarios where clinical presentation is ambiguous, imaging techniques can be instrumental in confirming the diagnosis and excluding other conditions. Plain radiographs help identify calcification in the flexor-pronator tendons or traction osteophytes and are particularly valuable for patients with a traumatic or acute onset of pain.[11] Radiographs are crucial for detecting bony abnormalities in the pediatric population, where growth plates are more prone to injury compared to tendons.[12]

Magnetic resonance imaging (MRI) is the gold standard for diagnosing medial epicondylitis, characterized by findings such as a thickened common flexor tendon sheath and increased T2 signal intensity.[5] In addition, MRI can identify other potential intra-articular or soft tissue complications, including osteochondritis dissecans, loose bodies, or ulnar collateral ligament injuries. Musculoskeletal ultrasound boasts high sensitivity and specificity (95.2% and 92%, respectively) for this condition.[17] The most common findings on ultrasound include focal, hypoechoic changes in the common flexor tendon, thickening of the tendon sheath, partial or full-thickness tears, neovascularization using Doppler, and cortical irregularities at the medial epicondyle.[12][17]. In addition, ultrasound facilitates dynamic imaging for assessing ulnar nerve subluxation and collateral ligament instability. When a patient's examination indicates the possibility of ulnar neuritis or neuropathy, electromyography and nerve conduction studies may serve as valuable supplementary diagnostic methods.

Treatment / Management

Nonoperative management is the foundation for the treatment of medial epicondylitis. Ciccotti et al have classified the nonoperative treatment of medial epicondylitis into 3 phases.[8]

• Phase 1: Cessation of offending activities or exercises in combination with pain-relieving modalities
• Phase 2: Guided physiotherapy and rehabilitation
• Phase 3: Modifications to previously offending activities

Conservative Management 

Initial pain relief is achieved with icing, especially after activities, and non-opiate analgesic medications, such as acetaminophen and non-steroidal anti-inflammatories, both oral and topical formulations.[12] Bracing, either with a counterforce elbow strap or a night splint, can benefit some patients. The strap should be positioned approximately 2 cm below the medial epicondyle to reduce tension on the tendon.[12] A nighttime volar wrist splint can prevent stress caused by sleeping positioning. Kinesiology tape is an alternative to traditional bracing methods. Although research on its effectiveness in medial epicondylitis is limited, its use has demonstrated benefits in lateral epicondylitis cases.[18] (A1)

Active participation in physical therapy is crucial. Therapy focuses on achieving a full range of motion without pain, followed by stretching and progressive isometric exercises. As improvement continues, resistive exercises are incorporated, aiming to surpass pre-injury muscle strength. Once repetitive exercises can be performed comfortably, patients can gradually resume sports or work-specific activities. The completion of guided therapy should transition into a maintenance exercise regime to maintain flexibility and strength and decrease the chance of recurrence.[8] Prevention strategies involve adjustments to sporting or occupational equipment and technique modifications. For tennis players, measures such as using a larger grip size on the racquet, loosening the strings, and enhancing serve and forehand techniques can mitigate stress on the flexor-pronator mass.[8]

Complementary Therapies

Corticosteroid injections are useful for short-term symptom relief, typically up to 6 weeks after the injection, but no long-term benefits have been observed at 3 and 12 months post-injection.[19][20][21][19] Treatments such as prolotherapy, platelet-rich plasma, autologous blood, and botulinum toxin injections may also be effective. However, these have primarily been studied in lateral epicondylitis, with further research needed to assess their efficacy in medial epicondylitis.[22][23] Caution is advised with injections due to the proximity of the target site to the ulnar and medial antebrachial cutaneous nerves, and ultrasound needle guidance is recommended.[24][25][26] Topical nitroglycerin or glyceryl trinitrate has short-term benefits in lateral epicondylitis, but the efficacy varies based on the application site.[27] Other alternative therapies, such as extracorporeal shock wave therapy, massage, transcutaneous electrical stimulation, iontophoresis, phonophoresis, and ultrasonography, may offer benefits, although evidence of their effectiveness is limited.(A1)

Surgical Intervention

Surgical management may be considered if no improvement is observed with conservative treatments over 6 to 12 months.[5] Given the proximity to the ulnar nerve and ulnar collateral ligament, an open surgical approach is preferred. The surgery involves debridement of the degenerated tendon, common flexor tendon release at the medial epicondyle, and epicondyle cortical drilling to enhance vascularity. If ulnar neuropathy is present, transposition may also be performed. Postoperative care includes rest and splinting with therapy beginning 7 to 10 days postoperatively to improve the passive range of motion. Gentle isometric exercises are introduced 3 to 4 weeks post-surgery, followed by a progressive strengthening program between 6 and 12 weeks. A gradual return to sport-specific activities commences between 3 and 6 months.[5][8] 

Differential Diagnosis

The differential diagnosis for medial epicondylitis includes, but is not limited to, the following:[5][14]

• Ulnar neuropathy
• Cervical radiculopathy
• Ulnar (medial) collateral ligament sprain or tear
• Valgus extension overload syndrome
• Posteromedial elbow impingement
• Synovial plica
• Synovitis
• Elbow bursitis
• Rheumatoid arthritis
• Osteoarthritis
• Osteochondritis dissecans
• Occult fracture
• Myofascial pain complex
• Shingles

Prognosis

The prognosis for individuals with medial epicondylitis is generally positive, with many experiencing relief through physical therapy, non-opiate pain relievers, and the use of braces. However, the prognosis can be more unpredictable compared to treatment for lateral epicondylitis. For individuals who do not respond to initial treatments, treatment options such as corticosteroid injections, prolotherapy, or platelet-rich plasma injections may be effective. Surgery may be considered if the patient has failed conservative therapies. Patients have shown a worse prognosis if they have concomitant ulnar neuritis.[5]

Complications

Most individuals can return to their normal activities and functions with successful treatment. Although complications are rare, persistent pain or recurring symptoms are the most common issues. Potential complications in cases requiring surgical management include nerve injury (to the medial antebrachial cutaneous nerve or ulnar nerve) or infection. For treatment-resistant cases that necessitate surgery, pain is likely to improve, but approximately 20% of patients may not regain their previous level of athletic performance.[11]