Weight-bearing Casts Effective in Treating Achilles Tendon Ruptures

By: Jennie McKee

Jennie McKee

Weight-bearing casts in the nonsurgical treatment of Achilles tendon ruptures appear to offer outcomes that are at least equivalent to outcomes of non–weight-bearing casts, according to the results of a randomized, controlled study. The study, conducted in New Zealand by Simon Young, MD, and colleagues, compared the outcomes of traditional, non–weight-bearing casts with weight-bearing casts equipped with a Bohler iron brace.

Collecting data
Researchers recruited 84 patients (43 males and 41 females; average age, 39.7 years) with an acute Achilles tendon rupture who were seen in the emergency departments of three hospitals in Auckland, New Zealand, or were referred by a general practitioner between 2007 and 2009.

Patients were included if they met the following criteria:

  • age older than 18 years
  • unilateral Achilles tendon rupture
  • seen within 72 hours of injury
  • able to attend a 6-month review
  • willing to participate in 12- and 24-month follow-up phone calls

Patients with previous tendon ruptures, previous tendon surgery, open injury, or multiple injuries were excluded.

Within 1 week of injury, patients who consented to participate in the study were randomized to receive an equinus cast—either a weight-bearing cast fitted with a Bohler iron (42 patients), or a traditional non–weight-bearing cast (42 patients). All patients were treated with a set protocol and had a total cast time of 8 weeks.

A third party with no affiliations to the investigators or patients enrolled the patients using computer-generated, sealed envelopes opened before treatment. Researchers recorded the patient’s age, sex, occupation, ankle activity index (modified Tegner score) and time elapsed between injury and casting prior to applying the cast.

Investigators administered detailed muscle dynamometry testing at 6 months, in which study participants performed five isokinetic plantarflexion and dorsiflexion cycles at three test speeds, including 30 degrees, 90 degrees, and 240 degrees per second. Researchers compared the peak torques generated at each speed by the injured limb to those generated by the contralateral limb to provide a final isokinetic strength score, according to the Leppilahti scale (a standardized protocol for evaluating recovery after Achilles tendon ruptures). Researchers conducted follow-ups with all patients at 1 and 2 years after treatment.

Primary outcome measures included patient satisfaction, time to return to work, and overall re-rupture rates. The following secondary outcomes measures were also used: return to sports, ankle pain and stiffness, footwear restrictions, and patient satisfaction.

Analyzing outcomes
Researchers found that one patient in the Bohler iron group and two patients in the non–weight-bearing group sustained re-ruptures (P = 0.62) (
Table 1). No complications occurred in either group.

In addition, 58 percent of patients in the weight-bearing group returned to work within 4 weeks, while 43 percent of those in the non–weight-bearing group returned to work in that period. Although this indicated a trend toward earlier return to work in the weight-bearing group, the difference was not statistically significant.

At 1 year, reported the authors, “the self-rated section of the Leppilahti questionnaire, the ankle Tegner score, and the self-rated Achilles tendon condition score revealed no statistically significant differences between the groups.”

“In the weight-bearing group, 63 percent of patients reported freedom from pain at 12 months, compared to 51 percent reporting freedom from pain in the non–weight-bearing group,” noted the investigators.

“The overall re-rupture rate in this study is low,” they added, “which we believe supports the continued use of initial nonsurgical management in the treatment of acute ruptures.”

Dr. Young’s coauthors for “Weight Bearing in the Non Operative Treatment of Acute Achilles Tendon Ruptures: A Randomized Controlled Trial” included Alpesh Patel, MD (no conflicts); Stephanie van Dijck, MD (no conflicts); Matthew Tomlinson, MD (Synthes); Wesley P. Bevan (no conflicts); and Peter McNair, PhD, PT (no conflicts). Dr. Young reports no conflicts.

Funding support for the study was provided by the Wishbone Foundation.