Prognostic factors for traumatic elbow osteoarthritis after terrible triad surgery, and functional impact

Introduction: Terrible triad (TT) of the elbow almost always requires surgery to prevent progression to chronic instability and more or less inevitable osteoarthritis. Progression toward osteoarthritis after well-conducted surgery and associated risk factors have been little reported. We performed a retrospective study: (1) to assess rates of post-traumatic elbow osteoarthritis after surgical treatment of TT; (2) to assess functional impact; and (3) to identify prognostic factors.

Hypothesis: Prevalence of osteoarthritis after surgical treatment of TT is high, impairing functional results.

Material and method: A single-center retrospective study included 53 patients, with a mean age of 50±17.8 years (range, 21-84 years), undergoing surgery for acute TT in our department. All received clinical examination with ranges of motion and Mayo Elbow Performance Index (MEPI) and radiographic assessment at a minimum 1 year's follow-up. Osteoarthritis at last follow-up was assessed on elbow X-ray in the humero-ulnar and radio-condylar compartments on the Broberg-Morrey classification. Functional impact on range of motion and MEPI and prognostic factors were assessed on Student test or ANOVA and Chi² or Fisher test.

Results: Prevalence of Broberg-Morrey grade 2 or 3 osteoarthritis was 45.3% (24/53) in the humero-ulnar compartment and 50% (25/50) in the radio-condylar compartment. Humero-ulnar osteoarthritis impaired MEPI (76.3 points with versus 88.4 points without; p=0.003), flexion-extension (102.3° versus 115.2°; p=0.043) and pronation-supination (138.8° versus 159.3°; p=0.006). Radio-condylar osteoarthritis had no significant impact on MEPI (81.4 points with and 84.4 points without; p=0.47), flexion-extension (104.8° and 113°; p=0.23) or pronation-supination (141.8° and 156.4°; p=0.2). Humero-ulnar osteoarthritis at last follow-up was associated with dislocation or subluxation on immediate postoperative lateral view (45.8% with versus 10.3% without; p=0.004) and at last follow-up (20.8% versus 3.4%; p=0.047) and with postoperative complications (54.2% and 27.6%; p=0.049). Radio-condylar osteoarthritis at last follow-up was associated with radial head replacement rather than internal fixation (respectively, 92% and 48%; p=0.0007) and excessively high radial head implant positioning (47.8% versus 0%; p=0.023).

Conclusion: Prevalence of traumatic osteoarthritis after TT surgery was high, at 45.3% in the humero-ulnar compartment and 50% in the radio-condylar compartment, with clinical impact in humero-ulnar involvement.

Level of evidence: IV; cohort study without control group.