Insertional Achilles tendinitis and Haglund's deformity.

BACKGROUND: Haglund's deformity is an enlargement of the posterosuperior prominence of the calcaneus, which is frequently associated with insertional Achilles tendinitis. To our knowledge, no study has been done successfully correlating the characteristics of a Haglund's deformity with insertional Achilles tendinitis. The purpose of our study was to analyze the characteristics of a Haglund's deformity in patients with and without insertional Achilles tendinitis to see if there was a correlation.
METHODS: The study was a retrospective radiographic review of a single surgeon's patients with insertional Achilles tendinitis from 2005 to 2008. Our study population consisted of 44 patients, 48 heels (22 male, 22 female) with insertional Achilles tendinitis, with a mean age of 52 (range, 23 to 79) years. Our control population consisted of 50 patients (25 males, 25 females) and 50 heels without insertional Achilles tendinitis with a mean age of 55.6 (range, 18 to 89) years. We introduced two new measurements of the Haglund's deformity in this study: the Haglund's deformity height and peak angle. A standing lateral foot or ankle radiograph was analyzed for each patient and the following measurements were made: Haglund deformity height and peak angle; Bohler's angle; Fowler-Philip angle; and parallel pitch sign. We also looked for the presence of calcification in the study group and the length and width of the calcification. Unpaired t-test was used to analyze the measurements between the groups. Ten patients' radiographs were re-measured and correlation coefficients were obtained to assess the reliability of the measuring techniques.
RESULTS: For the insertional Achilles tendinitis group, the mean Haglund's deformity height was 9.6 (range, 5.3 to 15.3) mm and the mean Haglund's deformity peak angle was 105 (range, 87 to 123) degrees. Calcification was present in 35 of 48 or (73%) of patients with a mean length of 13.3 (range, 3.2 to 41.9) mm and mean width of 4.5 (range, 1.0 to 10.4) mm. In the control group, the mean Haglund's deformity height was 9.0 (range, 5.2 to 12.1) mm and the peak angle was 105 (range, 91 to 124) degrees. Bohler's angle and Fowler-Philip angle were also similar between the groups and the positive parallel pitch sign was actually more prevalent in the control group (60% versus 41.7%). None of the differences in measurements between the groups achieved statistical significance.
CONCLUSION: A Haglund's deformity was not indicative of insertional Achilles tendinitis and was present in asymptomatic patients. Also, a majority of the insertional Achilles tendinitis patients had calcification at the tendon insertion. We believe it is possible removing the Haglund's deformity may not be necessary in the operative treatment of insertional Achilles tendinitis.