[Experiences with Eaton-Littler reconstruction for therapy of ligament instability of the thumb saddle joint]

Painful instability of the thumb carpometacarpal joint is a rare diagnosis. Between October 1995 and August 1999, eight operations of ligament reconstruction for unstable thumb carpometacarpal joints were performed. We report on the follow-up of these patients which took place at an average time of 12.27 months (range 5 through 36 months) after the operation. Painful hypermobility of the non-arthrotic thumb carpometacarpal joint was the indication for performing the operation in all cases. By this operation, the joint capsule is reinforced in two planes: the existing palmar ligament of the carpometacarpal joint is reinforced while it provides ligament support for the radial aspect of the joint that is otherwise membranous. In our study, we compared the pinch strength, the overall strength of the hand, the motion of the thumb, and radiographic findings for the amount of subluxation before and after performing the operation. In addition, each result was investigated with the DASH-questionnaire (DASH = Disability of Arm--Shoulder--Hand). The results were good or excellent in six cases, satisfactory in one case, and poor in one case. Pinch strength increased from a preoperative average of 19.6 N to 34.3 N and the vigor increased from 84.8 N to 113.1 N. Subluxation on the radiographs could be reduced from an average of 6.0 mm to 3.5 mm. All operated patients were investigated using the DASH-questionnaire. Herein the average score was 22.92 on a scale whereby 0 reflects minimum and 100 maximum disability.

Our experience with the Eaton-Littler procedure for stabilisation of the hypermobile painful thumb carpometacarpal joint were mostly positive. The objective results as well as the results of the evaluation of the DASH-questionnaire could confirm this impression.