Ablösung und Refixierung des M. pronator quadratus mit einem Teil des M. brachioradialis Ansatzes

BACKGROUND: Most surgeons don't repair the pronator quadratus (PQ) muscle in palmar plate fixation of a distal radius fracture because experience has shown that PQ repair yields no functional advantage. However, repair of the PQ may offer finger flexor tendon protection.

METHODS: In 9 human cadavers, the PQ was detached with a strong rim of connective tissue consisting of a fibrous portion of the roof of the first extensor compartment (RFEC) and the palmar limb of the brachioradialis muscle (BR) insertion. The gross anatomy and the dimensions of the dissected tissue were measured. After fixation of a palmar plate, the PQ was repaired. Stability was tested with 100 passive maximum pronation and supination repetitions.

RESULTS: The average total width of the PQ with the strong rim of connective tissue consisting of the RFEC and the palmar limb of the BR insertion was 28 mm. Suture repair was possible in each specimen, and each palmar plate was completely covered distally.

CONCLUSION: This dissection of the PQ with a strong rim of connective tissue consisting of the RFEC and the palmar limb of the BR insertion may offer a way to cover the distal edge of a palmar plate in open reduction and internal fixation of a distal radius fracture that affords finger flexor tendon protection.