Effect of humeral condylar resection on strength and functional outcome after semiconstrained total elbow arthroplasty.

BACKGROUND: Under certain conditions it is standard practice to excise ununited humeral condyles during insertion of a semiconstrained total elbow prosthesis. Since the osseous origins of the common extensors and flexor-pronator muscles are lost, it has been postulated that this excision has a negative effect on strength. We are not aware of any previous study in which this issue has been investigated with use of standardized, objective testing of muscle strength. METHODS: We used objective testing to determine the effect of condylar resection on the muscle strength of the elbow, forearm, wrist, and hand in thirty-two patients who had undergone total elbow arthroplasty. To eliminate bias, the normal, contralateral limb served as the control, and all strength values are given as a percentage of the normal side. The humeral condyles were intact in sixteen patients and had been resected in the other sixteen. Patient demographics were similar in the two groups. RESULTS: There were no significant differences between the two groups with regard to strength of pronation (103% of the normal side in the group with intact condyles compared with 89% in the group with resection of the condyles; p = 0.40), supination (68% compared with 89%; p = 0.49), wrist flexion (66% compared with 56%; p = 0.46), wrist extension (75% compared with 65%; p = 0.40), or grip strength (83% compared with 72%; p = 0.40). There was also no difference between the two groups with regard to the Mayo Elbow Performance Score (79 points in the group with intact condyles compared with 77 points in the group with resection of the condyles; p = 0.67). CONCLUSIONS: Condylar resection has a minimal, clinically irrelevant effect on forearm, wrist, and hand strength and no effect on the Mayo Elbow Performance Score following total elbow arthroplasty. Thus, the findings of our study support the practice of condylar resection, which simplifies total elbow arthroplasty for many conditions.