Background: Elbow instability, particularly posterolateral rotatory instability (PLRI), has been reported in patients with refractory lateral epicondylitis (LE). However, evidence of diagnostic approach and surgical outcomes is lacking.
Purpose: To identify (1) the risk factors, clinical and radiologic-diagnostic characteristics, and (2) the treatment options and clinical outcome of LE with PLRI.
Study design: Systematic review.
Methods: We searched the PubMed, Ovid/MEDLINE, Cochrane Library, Google Scholar, Scopus, and EMBASE databases using keywords as well as Medical Subject Headings terms and Emtree using "(lateral epicondylitis OR tennis elbow) AND (instability OR posterolateral rotatory instability)" for English-language studies. We conducted a systematic review using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.
Results: In total, 8 articles comprising 6 level 4 and 2 level 3 studies were identified, including 249 patients (254 elbows). The main triggering factor was heavy labor activity (74/172; 43%). A total of 184 patients (73.9%) received either single (4/184; 2.2%) or multiple (180/184; 97.8%) steroid injections. Clinically, instability was always accompanied by pain in 9% of study individuals. Magnetic resonance imaging (MRI) revealed that radial collateral ligament (RCL) and lateral ulnar collateral ligament (LUCL) lesions were most common (18/79; 23%). The most common surgical procedure performed was arthroscopic RCL plication (62/120; 52%) followed by LUCL reconstruction (30/120; 25%). A ligament patholaxity sign was shown intraoperatively for 64% (44/69). Clinical outcomes ranged from good to excellent in all studies. The most common residual symptom was limited range of motion (11/18; 61%).
Conclusion: Instability can coexist and may be associated with refractory LE. The risk factors of instability associated with refractory LE are heavy labor and multiple steroid injections. A systematic approach to identify the clinical and MRI presentation of the condition followed by examination under anesthesia are necessary for affirmative diagnosis, as independent presentations may be misleading.
Keywords: elbow tendinopathy; joint instability; lateral epicondylitis; systematic review; treatment outcome.