The Effect of Midcarpal Versus Total Wrist Fusion on the Hand's Load Distribution During Gripping.

PURPOSE: To analyze the total grip force and load distribution of the hand with midcarpal fusion (MCF) and total wrist fusion (TWF). METHODS: Twelve patients with unilateral TWF and 12 patients with unilateral MCF were assessed at an average 64 months (range, 19-100 months) postoperatively. The total grip force and load distribution of both hands were measured by the Manugraphy system using 3 cylinder sizes. The load applied to 7 anatomical areas of the hand during cylinder grip was analyzed, comparing the operated and the nonsurgical hands. RESULTS: For the 100 mm and 150 mm cylinders, a significantly lower total grip force was found in hands operated with either TWF or MCF. For the 200 mm cylinder, there was a significant difference between nonsurgical hands and those with MCF but not between nonsurgical hands and those with TWF. For the 100 mm cylinder, the difference between nonsurgical and operated hands was greater in hands with TWF than those with MCF. For the load distribution of the hand, no differences between the operated and the nonsurgical hand were found for either MCF or TWF. CONCLUSIONS: MFC and TWF resulted in a reduced cylinder grip force. With respect to the load distribution, neither procedure influenced the relative contribution that each area of the hand produced during cylinder grip. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Midcarpal fusion is also indicated in patients with advanced carpal collapse and already highly restricted range of motion preoperatively.

Although midcarpal fusion is a well-accepted treatment of advanced carpal collapse, 1 question remains unanswered: is this technically demanding procedure worthwhile in wrists with an already highly restricted flexion-extension arc (FEA) of less than 60 degrees preoperatively? Therefore, a retrospective analysis of the records of 142 consecutive patients who had had a midcarpal fusion of the wrist was performed. There were 50 patients in group 1 (FEA < 60 degrees) and 92 patients in group 2 (FEA ≥ 60 degrees) with a mean follow-up of 23 months. Flexion-extension arc preoperatively and postoperatively, pain evaluated by a visual analog scale from 0 to 10 as well as the patients' upper extremity functioning captured with the Disabilities of the Arm, Shoulder and Hand questionnaire were statistically analyzed. Functional range of motion was defined as 5-degree wrist flexion and 30-degree wrist extension. Median wrist flexion before versus after midcarpal fusion was 18 versus 22 degrees and 23 versus 25 degrees for wrist extension in group 1. In group 2, the data were 42 versus 27 degrees and 43 versus 30 degrees, respectively. Midcarpal fusion led to an improvement of FEA in 52% of patients in group 1 but only in 5.4% of patients in group 2. In group 1, the median FEA improved by 122%, whereas the median FEA declined to 69% in group 2. Preoperatively 20% of patients in group 1 and 95% of patients in group 2 reached a functional range of motion for flexion/extension, which changed to 36% in group 1 versus 62% in group 2 postoperatively. The visual analog scale score improved for group 1 from 5.7 to 2.4 and for group 2 from 5.7 to 3.2, respectively. The postoperative DASH score was for both groups 33 points. Our data demonstrate that even in patients with a highly restricted range of motion in advanced carpal collapse, it is still reasonable to perform a midcarpal fusion instead of total wrist fusion.

Long-term results after midcarpal arthrodesis.

Background and Purpose Midcarpal arthrodesis is a well-accepted treatment option for advanced carpal collapse. In this study, we retrospectively assessed survival, analyzed complications and reviewed the long-term follow-up after midcarpal fusion. Materials and Methods The computerized medical records of 572 patients who had undergone 594 four-corner fusions between 1992 and 2001 were explored. Furthermore 56 patients with 60 midcarpal fusions were randomized for clinical and radiological follow-up at a mean of 14.7 years. Results Forty midcarpal fusions (6.7%) had to be converted into complete wrist arthrodesis. The reasons were ongoing pain in spite of a well-healed midcarpal fusion (31) or nonunion (9). Sixty-three patients (11%) required revision surgery because of nonunion (22), hematoma (8), wound infection (3) or persisting pain (31). In clinical follow-up the mean Disabilities of the Arm, Shoulder, and Hand (DASH) score was 20.4. Pain at rest was infrequent, a mild increase with daily activity was complained of (mean visual analog scale [VAS] 3.3). The mean active range of wrist motion for extension and flexion, ulnar and radial deviation and supination and pronation reached 62.5%, 68.4%, 94.7%, and mean grip strength 84.9% of the unaffected side. All patients had radiographic abnormalities, with frequent evidence of osteoarthritis of the lunate fossa. Patients with preserved carpal height appeared to have less pain, better DASH scores and a better range of motion. Conclusions The midcarpal arthrodesis is a long-lasting treatment option for advanced carpal collapse and has good long-term results. Level of Evidence Level IV, Therapeutic study.