Extension block pinning with percutaneous intramedullary reduction for dorsal PIP joint fracture-dislocation of the finger.

BACKGROUND

Dorsal fracture-dislocations of the proximal interphalangeal (PIP) joint can cause chronic pain, stiffness, and loss of motion. We present a minimally invasive method-extension block pinning combined with percutaneous intramedullary reduction and fixation-for unstable dorsal PIP fracture-dislocations and evaluate its radiologic and functional outcomes.

METHODS

Twenty consecutive patients with acute unstable dorsal PIP joint fracture-dislocations and persistent post-reduction subluxation were treated with this technique. In the treated cohort, volar articular involvement ranged from 30% to 70%. The procedure combines extension block K-wire pinning with intramedullary percutaneous reduction and supplementary fixation, allowing early motion. Range of motion (ROM), pain (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) scores, fingertip-to-palm distance, radiographic congruency, and complications were recorded and analyzed. Confidence intervals were calculated for key continuous variables.

RESULTS

At a mean follow-up of 18 months (range, 6-36), all fractures united with maintained reduction. Mean articular step-off improved from 2.1 mm preoperatively to 0.5 mm postoperatively (p < 0.001). Mean PIP joint motion increased from 5° to 84° (p < 0.001). VAS pain improved from 6.2 to 0.6, and DASH from 28 to 5 (both p < 0.001). Eighteen joints achieved <1 mm step-off at final follow-up; two had mild incongruity without symptoms. No infections, hardware failures, or recurrent subluxations occurred.

CONCLUSION

This combined percutaneous technique appears to be a reproducible, minimally invasive option for selected unstable dorsal PIP fracture-dislocations, restoring articular congruity while permitting early mobilization. The findings demonstrate promising functional and radiological outcomes; however, given the retrospective design, small sample size, and absence of a control group, these results should be interpreted as preliminary and hypothesis-generating. Prospective comparative studies are required to validate these observations.

LEVEL OF EVIDENCE: IV - Therapeutic case series.