Dorsal blocking orthoses for proximal interphalangeal joint volar plate injuries: A retrospective cohort study investigating the impact of joint angle on patient outcomes

Injuries to the proximal interphalangeal joint (PIPJ) of the fingers are commonly treated in hand therapy departments. Conservative management for PIPJ volar plate injuries typically involves a dorsal blocking orthosis and flexion exercises. Historically hand therapists have placed the PIPJ in varying degrees of flexion but the optimal angle is unknown. To compare the outcomes of two treatment groups who received dorsal blocking orthoses: Those who the orthosis was positioned in neutral compared to those in 25–30° of flexion. Retrospective cohort study. Patients treated by the hand therapy service at a major metropolitan hospital network in Melbourne, Australia, for conservative management of a PIPJ volar plate injury over a three-year period were included in our study. Data regarding patient demographics, digits affected and injury type were collected. Outcomes included presence of a fixed flexion deformity (FFD), amount of hand therapy received and total active flexion at the PIPJ. One hundred and eleven participants were included in our study. The mean age was 26 and 59 (53%) were males. Seventy two (64%) participants received a dorsal blocking orthosis positioned in neutral and 39 (35%) were positioned in 25–30° flexion at the PIPJ. Participants whose orthosis was positioned at 25–30° had an average of 24 more minutes in hand therapy (which equates to approximately one appointment) compared to those whose PIPJ was positioned in neutral (p=0.006, d=0.5). Eight percent less participants developed a FFD (p = 0.24) and 13% more participants achieved full flexion (p = 0.06) in the group who received a dorsal blocking orthosis in neutral, however these results were not statistically significant. PIPJ volar plate injures treated in an orthosis positioned in neutral required fewer hand therapy appointments. There was no statistically significant difference between groups regarding development of a FFD or full flexion. •Retrospective study, conservative management of volar plate injuries.•Positioning the PIPJ in neutral results in less time in hand therapy.•Patients positioned in neutral have better clinical outcomes.