Sex Differences in Outcome After an Acute Achilles Tendon Rupture

Tendon healing differs between the sexes. Comparisons in outcome between the sexes after an Achilles tendon rupture are often not possible because of the small cohort (<20%) of women.To evaluate whether there are any differences in outcome between the sexes by combining the data from 2 large randomized controlled trials that used identical outcome measures.Cohort study; Level of evidence, 3.Included in the evaluation were patients from 2 consecutive randomized controlled trials comparing surgical and nonsurgical treatment performed at our research laboratory. Patients who had a rerupture were excluded from analysis. A total of 182 patients (152 males, 30 females), with mean ± SD age of 40 ± 11 years, were included; 94 (76 males, 18 females) were treated with surgery and 88 (76 males, 12 females) nonsurgically. Patient-reported outcome was evaluated using the Achilles tendon Total Rupture Score (ATRS), and the functional outcome was measured with a heel-rise test (measurement of muscular endurance and heel-rise height) at 6 and 12 months after injury.Male patients had a greater improvement in heel-rise height at 12 months (P = .004). When each treatment group was analyzed separately, it was found that female patients had significantly (P < .03) more symptoms after surgical treatment (mean ± SD ATRS, 59 ± 24) compared with males at 6 (73 ± 19) and 12 months (74 ± 27 vs 86.5 ± 17). This sex difference was not found in the nonsurgical treatment group. For the entire group, there were no significant differences between treatments on ATRS at 6 and 12 months. The surgical group had significantly better results compared with the nonsurgical group in heel-rise endurance at 6 and 12 months and in heel-rise height recovery at 6 months (P < .03 for both).Sex differences were demonstrated, and female patients had a greater degree of deficit in heel-rise height as compared with males, irrespective of treatment. Females had more symptoms after surgery both at 6 and 12 months, but this difference was not found when treated nonsurgically.Further research is needed to determine whether women will benefit more from nonsurgical compared with surgical treatment after an Achilles tendon rupture.