dislocations of the distal interphalangeal ( dip ) joint are usually associated with fractures of its base . dorsal irreducible dislocation of this joint is an especially rare injury , with less than twenty cases reported in english literature since 1940 . the injury is the distal counterpart of the complex metacarpophalangeal ( mcp ) dislocation , with many parallels . however , this is liable to be missed and mismanaged unless a high index of suspicion is maintained , especially in a multiply injured patient . we present a case report with a brief review of the literature and pointers towards managing this problem . a 46-year - old right - handed farmer sustained a motor vehicle accident , resulting in bilateral distal radius fractures and a closed dorsal dislocation of the dip joint of the left middle finger . x - rays showed an increased joint space , along with a dorsoulnar dislocation [ figure 1a and b ] . this suggested soft - tissue interposition , possibly the volar plate of the dip joint . closed pinning of the ipsilateral distal radius fracture was performed under a brachial plexus block , before proceeding to reduction of the finger joint . closed reduction was attempted by exaggerating the hyperextension and ulnar deviation deformity , followed by gentle pressure over the dorsally palpable base of the distal phalanx . ( a and b ) x - ray views showing dorsoulnar distal interphalangeal joint dislocation with increased joint space open reduction was planned after a couple of trials of closed reduction failed . under an arm tourniquet control , a volar zig - zag incision was made centred on the flexion crease of the dip joint . on exposure of the joint , the ulnar condyle of the head of the middle phalanx was found prominent volarly with the flexor digitorum profundus tendon entrapped behind it , with rupture of the a5 pulley . the volar plate was pulled out and reduction completed by manoeuvring the flexor tendon around the middle phalanx head [ figure 3 ] . as the volar plate was avulsed proximally , it was then repaired to the periosteum over the middle phalanx with nonabsorbable sutures ( 5 - 0 prolene ) . a follow - up x - ray at 2 months showed maintenance of reduction [ figure 5 ] . note volar plate interposition ( white arrow ) and displaced profundus tendon ( black arrow ) intraoperative picture post - reduction with centralised profundus tendonvolar concentric reduction of the joint on lateral view with image intensifier ( a and b ) follow - up x - ray showing concentric reduction the first report of an irreducible dip dislocation was by selig and schein in 1940 , who ascribed the irreducibility to buttonholing of the middle phalanx head through the volar plate . over the years , various reports have identified more causes , which are : profundus tendon entrapment behind middle phalanx head , volar plate interposition and buttonholing of the middle phalanx head through a rent in the volar plate or flexor tendon . in the thumb , these injuries have a high incidence of being missed initially as well as late presentation . moreover , excessive traction may actually convert a simple dislocation into a complex one , by pulling the avulsed volar plate into the joint space . once increased joint space is noted on x - rays , closed reduction is to be attempted only by pressure on the distal phalanx base . repeated attempts are unlikely to be successful . in a report and review of literature , abouzahr and poblete found only 12 such cases reported till 1997 having included both open and closed dislocations . they concluded that volar plate interposition was the culprit in closed injuries while the buttonholed profundus tendon caused irreducibility in open injuries . we also feel that , in our case , the displacement of the tendon was the primary impediment to reduction rather than the volar plate interposition . however , this interposition has to be identified and corrected before any attempt at joint reduction is made . similar to the controversy over the mcp dislocation , controversy exists in the approach for open reduction . the dorsal transverse approach , with midlateral extensions , the approach allows easy handling of the interposed tissues but is fraught with wound healing issues . the volar approach , on the other hand , heals well , but with some involved dissection needed to safely extricate the trapped tissues . it also allows repair of the volar plate or tendon , which ensures stability . on the basis of our experience with mcp and proximal interphalangeal joint dislocations k - wire fixation is not necessary if the joint is stable after open reduction . if reduction is unstable , it is worthwhile searching for the soft - tissue components involved and repairing the injured structures . these could be the volar plate , flexor tendon , capsule and/or collateral ligaments . for proper delineation of the injury and subsequent repair , we instructed the patient to use the finger within limits of pain while avoiding strong gripping activities for 3 weeks . however , it is better to safeguard the reduction with a splint if any doubt on the stability of the reduction or patient 's compliance exists . diagnosis requires a high index of suspicion , and x - rays should definitely be obtained . if an increase in joint space is noted , open reduction will usually be necessary .