Salter-Harris type III dorsal fracture-dislocation of the second and third proximal interphalangeal joints: a case report.

BACKGROUND

Paediatric fracture-dislocation of the second (2nd) or third (3rd) proximal interphalangeal (PIP) joint is a rare injury and often associated with growth plate injury. There are few case reports regarding this uncommon injury, and no study has reported on Salter-Harris (SH) -type III injuries.

CASE PRESENTATION: We present the case of a 6-year-old softball player who suffered from irreducible SH-type III fracture-dislocations of the 2nd and 3rd PIP joints at different time points, which were treated by open reduction without internal fixation. The injury mechanism for the fracture-dislocations of the 2nd and 3rd PIP joints was the same when he caught a ball with his right hand in a left-hand softball globe. The palmar epiphysis of the middle phalanx was displaced dorsally in an upside-down position and was interposed within the PIP joint during both surgeries. After reducing the bony fragment gently using an elevator, the fragment remained congruent and stable in the extension of the PIP joint without instability of the collateral ligaments under fluoroscopy. Therefore, internal fixation of the fragment was not performed at both surgeries. At the latest follow-up examinations (7 years after surgery for the 2nd PIP joint and 5 years after surgery for the 3rd PIP joint), the patient showed no pain or restrictions in finger range of motion. However, the plain radiography showed early closure of the growth plate of the 2nd middle phalanx.

CONCLUSIONS

We herein firstly presented the case of a patient with Salter-Harris type III irreducible fracture-dislocation of the 2nd and 3rd PIP joints that required open reduction without internal fixation. The injury mechanism and the location of the displaced palmar epiphysis of the middle phalanx were specific. At the midterm follow-up examinations, the patient showed no pain or restriction of the finger range of motion, although early closure of the growth plate in the 2nd middle phalanx was found on plain radiography.