title: Stener-like lesions of collateral ligament ruptures of the metacarpophalangeal joint of the finger.
abstract: BACKGROUND
  The Stener lesion of the ulnar collateral ligament of the metacarpophalangeal (MP) joint of the thumb is characterized by an interposition of the adductor aponeurosis between a distally avulsed ligament and its insertion into the base of the proximal phalanx. Stener-like lesions of the MP joint of the finger have been previously reported in only a few cases.
  
  
  METHODS
  The authors experienced 38 cases of collateral ligament injuries of the MP joint of the finger. The two most frequently affected sites were the radial side of the little finger (21 cases) and the radial side of the ring finger (8 cases). We have previously reported some of these cases (22 cases), as well as clinical features and arthrographic findings. One Stener-like lesion in a collateral ligament injury of the MP joint of the ring finger was also reported earlier (Ishizuki, 1988). Additionally, Stener-like lesions were found postoperatively in six of eight cases surgically treated for collateral ligament injuries of the MP joint of the finger (little finger involvement in 5 cases and long finger involvement in 1 case).
  
  
  RESULTS
  We experienced six cases of a Stener-like lesion of the MP joint of the finger. In five of these cases the distally avulsed collateral ligament was trapped by the opened window of the injured sagittal band. In the other case the ligament was avulsed at a proximal site, and the ruptured end was trapped by the sagittal band. All of the little fingers involving Stener-like lesions were abducted and unable to adduct. Therefore, an abducted little finger is an important sign of this lesion and is considered to warrant surgical treatment. Arthrograms provided information useful for identifying the lesions. In the radial three fingers, palpation of the tumor at the level of the collateral ligament may also be an important examining tool for identifying a displaced ruptured collateral ligament of the MP joint of the finger.
  
  
  CONCLUSIONS
  We experienced six cases of Stener-like lesions of the MP joint of the finger. In all cases, the avulsed collateral ligament was trapped by the ruptured sagittal band. Surgical treatment was thought to be indicated in these cases. Therefore, it is important to avoid overlooking Stener-like lesions of the MP joint of the finger.
authors.affiliation: Department of Orthopaedic Surgery, Tsuchiura Kyodo General Hospital, 11-7 Manabeshinmachi, Tsuchiura-shi, Ibaraki, 300-0053, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ishizuki
authors.forename: Takayuki
authors.initials: T
authors.lastname: Sugihara
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Wakabayashi
authors.forename: Ritsurou
authors.initials: R
authors.lastname: Shirasaka
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Aoyama