Purpose:
Vascularized toe proximal interphalangeal joint (PIPJ) transfer provides an autologous repair
for the post-traumatic finger PIPJ. The overall clinical results were improved, but
suboptimal outcomes were observed in our series. Secondary revision surgeries, including
corrective osteotomy, joint contracture release, and tenolysis, have to be done to obtain
better outcomes. This study aimed to analyze the risk factors relating to inferior functional
outcomes.
Materials and Methods:
In this retrospective study, 68 vascularized toe PIPJ transfers of 64 patients between
November of 2008 and January of 2021 was reviewed. The average follow-up of these cases
was 30 months. Extensor reconstruction with centralization of the lateral band was
excluded from the study. Outcomes with the degrees of ROM and extensor lag were
followed up at the clinic, and degrees of transferred PIPJ dorsal angulation were measured via
X-ray from finger lateral view. We reviewed charts for factors that might impact outcomes,
including baseline characteristics and initial trauma mechanism preoperatively; extensor
reconstruction methods, central tendon type of toe, resect toe length, and osteosynthesis
method perioperatively; revision surgery, rehabilitation compliance, and union of osteosynthesis sites postoperatively. Bony width discrepancy between donor and recipient sites was measured via X-ray from finger A-P view, and we obtained ratio by dividing
recipient width by donor width.

Results:
Greater ROM was observed in extensor reconstructed by Te’s technique compared by Stack's procedure (β = 9.07; p = 0.049). Applying propensity score analysis,
EDL-EDC repair group had inferior ROM (β = -14.701; p = 0.006), more extensor lag (β = -
14.815; p < 0.001), less percentage of usage (β = -34.456; p = 0.001) compared with Stack's
or Te’s group. Generalized estimating modeling also showed that initial trauma mechanisms
with direct PIPJ surface damage, extensor tendon involvement, and a replanted finger
significantly affected the functional outcomes before revision surgery was performed. For
the final outcomes after revision surgery, only replantation correlated with the incidence of
ROM inferior to average (p < 0.05). As to dorsal angulation after VJT without receiving
corrective osteotomy, generalized estimating modeling showed that osteosynthetic sites with
delayed malunion have more angulation degree (β = 20.879; p <0.001), compared with well
union digits; osteosynthesis with parallel interosseous wire has more angulation degree (β =
6.354; p <0.001), compared with 90o-90o interosseous wire.
Conclusion:
The study found that re-creation of the extensor insertion for the transferred joints seems to
have non-inferior results than the toe joints with native central slip insertion. Initial trauma
mechanisms with direct joint surface damage and extensor tendon involvement have a higher
risk for secondary revision, while replantation could be an unfavorable factor leading to an inferior outcome.

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