A 16-Year Longitudinal Study of Long-term Clinical and Radiographic Outcomes in Dorsal Proximal Interphalangeal Joint...

Dorsal fracture-dislocations of the proximal interphalangeal (PIP) joint often lead to stiffness, pain, and post-traumatic osteoarthritis (PTOA). This study evaluated long-term clinical outcomes and radiographic PTOA following surgical treatment of unstable PIP fracture-dislocations.

We conducted a retrospective cohort study of 25 patients (27 fingers) treated with extension block pinning for unstable dorsal PIP fracture-dislocations between 2000 and 2009. Follow-ups in 2010 and 2021 assessed active range of motion (AROM) in PIP and distal interphalangeal (DIP) joints, grip strength, and pain. Postoperative radiographs were analyzed for articular surface involvement and step-off. Post-traumatic osteoarthritis was graded using Kellgren-Lawrence, Kallman, and Osteoarthritis Research Society International scales by 3 blinded hand surgeons, with intraobserver and interobserver reliability assessed.

Over a follow-up of up to 16 years, PIP AROM remained stable. Patients aged ≥45 had reduced PIP AROM and more frequent pain. Greater pain was also seen in those with >0.5 mm articular step-off or advanced radiographic osteoarthritis (OA). Osteoarthritis progression was associated with reduced PIP AROM and residual step-off. The Kallman scale showed the most significant OA progression, especially with ≥50% joint surface involvement. Osteoarthritis grading showed substantial intraobserver and interobserver reliability.

Long-term function after extension block pinning of dorsal PIP joint fracture-dislocations remained, though age over 45 years and residual step-off predicted reduced AROM, pain, and OA progression.