Background.
Immobilization and early motion are both used as part of non-surgical treatment of hyperextension injuries to the proximal interphalangeal (PIP) joints of the hand but there is no consensus as to the most effective regimen.

Aims/objectives.
This systematic review evaluates the effects of immobilization, protected mobilization and
unrestricted mobilization on outcome after PIP joint hyperextension injuries.

Methods.
We searched the Cochrane, MEDLINE, EMBASE, CINAHL and PEDro databases, Zetoc, trial
registers and reference lists of articles. Randomized and quasi-randomized studies were included if they compared the conservative management of acute (less than 1 month) hyperextension injuries of the PIP joint, using two or more of the following interventions: unrestricted
motion, buddy strapping, immobilization or protective splinting. Two independent assessors evaluated the methodological quality of the studies using the Cochrane Collaboration Risk of Bias tool.
Results.
Three trials met the inclusion criteria. Variations in the interventions meant that results could not be pooled. One trial compared immobilization to unrestricted mobility, one compared immobilization to protected motion and one compared immobilization for one week versus three weeks. Sample size varied from 40 to 181 patients and duration of follow-up ranged from six
months to three years. Overall, patients who sustained a hyperextension injury to the PIP joint, managed without surgery, demonstrated similar outcomes regardless of the amount of motion allowed or when motion was initiated. All trials were more than 15 years old, of low methodological quality and lacked patient-reported functional outcome measures.

Conclusions.
This systematic review demonstrates that there is a lack of evidence regarding the most effective
method of rehabilitation of non-surgically managed PIP joint hyperextension injuries