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Published on: December 8, 2023
Insertional Achilles tendinitis and Haglund's deformity
Steve Kang1, David B Thordarson, Timothy P Charlton
1USC Department of Orthopaedic Surgery, Los Angeles, CA 90033, USA.
Insights
Haglund deformity does not indicate insertional Achilles tendinitis, as it occurs in asymptomatic individuals. Surgical removal of Haglund deformity may not be necessary for treating insertional Achilles tendinitis.
Area of Science:
- Orthopedic surgery
- Radiology
- Sports medicine
Background:
- Haglund deformity, an enlarged calcaneal prominence, is often linked to insertional Achilles tendinitis.
- No prior studies have correlated Haglund deformity characteristics with insertional Achilles tendinitis.
- This study aimed to identify potential correlations between Haglund deformity features and insertional Achilles tendinitis.
Purpose of the Study:
- To analyze Haglund deformity characteristics in patients with and without insertional Achilles tendinitis.
- To determine if specific Haglund deformity measurements correlate with insertional Achilles tendinitis.
- To investigate the prevalence of calcification in the Achilles tendon insertion among patients with Haglund deformity.
Main Methods:
- Retrospective radiographic review of 44 patients with insertional Achilles tendinitis and 50 controls.
- Introduction of novel measurements: Haglund deformity height and peak angle.
- Analysis of radiographic parameters including Bohler's angle, Fowler-Philip angle, and parallel pitch sign.
Main Results:
- No statistically significant differences in Haglund deformity height or peak angle between groups.
- Positive parallel pitch sign was more common in the control group (60% vs. 41.7%).
- Calcification at the tendon insertion was observed in 73% of the insertional Achilles tendinitis group.
Conclusions:
- Haglund deformity is not a reliable indicator of insertional Achilles tendinitis.
- The presence of Haglund deformity does not necessitate its surgical removal for treating insertional Achilles tendinitis.
- Calcification is common in the Achilles tendon insertion of patients with insertional Achilles tendinitis.
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.
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