Nonoperative treatment of acute rupture of the Achilles tendon: results of a new protocol and comparison with operative treatment

FGF gene expression in injured tendons as a prognostic biomarker of 1-year patient outcome after Achilles tendon repair

PURPOSE

Healing outcome after Achilles Tendon Rupture (ATR) is variable and unsatisfactory. Many ATR patients still exhibit pain, functional deficits and limitations in walking one-year post-surgery. The present study was designed to investigate the association between the expression of healing biomarkers and patient outcome after ATR.

METHODS

Tendon biopsies were collected from 25 ATR patients during surgery. At 1-year post surgery, all patients completed questionnaires; Achilles tendon Total Rupture Score (ATRS) and Foot and Ankle Outcome Score (FAOS), and were tested for functional outcomes by heel-rise test. In biopsies, FGF, COL III, FN, COL I and MMP-9 mRNA levels were assessed by quantitative RT-PCR while protein expression was studied by immunohistochemistry (IHC).

RESULTS

Our analysis confirmed the presence of FGF, COL III, FN, COL I and MMP-9 at mRNA and protein levels in tendon biopsies. FGF gene expression associated positively with improved total ATRS and better functional outcomes. Additionally, FGF mRNA levels were associated with less pain, less running limitations and less loss in physical activity. In addition, higher COL III mRNA expression was associated with more tendon strength.

CONCLUSION

Our findings indicate that FGF gene expression is associated with improved patient-reported outcome. FGF expression in surgical biopsies could potentially be used to assist the prognostic evaluation of patient outcome and may be used as a predictor for healing. However, further studies are needed to evaluate the role of FGF in Achilles tendon healing.

LEVEL OF EVIDENCE

II.

Therapeutic Effects of Doxycycline on the Quality of Repaired and Unrepaired Achilles Tendons

BACKGROUND

Achilles tendon tears are devastating injuries, especially to athletes. Elevated matrix metalloproteinase (MMP) activity after a tendon injury has been associated with deterioration of the collagen network and can be inhibited with doxycycline (Doxy).

HYPOTHESIS

Daily oral administration of Doxy will enhance the histological, molecular, and biomechanical quality of transected Achilles tendons. Additionally, suture repair will further enhance the quality of repaired tendons.

STUDY DESIGN

Controlled laboratory study.

METHODS

Randomized unilateral Achilles tendon transection was performed in 288 adult male Sprague-Dawley rats. The injured tendons were either unrepaired (groups 1 and 2) or surgically repaired (groups 3 and 4). Animals from groups 2 and 4 received Doxy daily through oral gavage, and animals from groups 1 and 3 served as controls (no Doxy). Tendons were harvested at 1.5, 3, 6, and 9 weeks after the injury (n = 18 per group and time point). The quality of tendon repair was evaluated based on the histological grading score, collagen fiber orientation, gene expression, and biomechanical properties.

RESULTS

In surgically repaired samples, Doxy enhanced the quality of tendon repair compared with no Doxy ( P = .0014). Doxy had a significant effect on collagen fiber dispersion, but not principal fiber angle. There was a significant effect of time on the gene expression of MMP-3, MMP-9 and TIMP1, and Doxy significantly decreased MMP-3 expression at 9 weeks. Doxy treatment with surgical repair increased the dynamic modulus at 6 weeks but not at 9 weeks after the injury ( P < .001). Doxy also increased the equilibrium modulus and decreased creep strain irrespective of the repair group. Doxy did not have a significant effect on the histology or biomechanics of unrepaired tendons.

CONCLUSION

The findings indicate that daily oral administration of Doxy accelerated matrix remodeling and the dynamic and equilibrium biomechanics of surgically repaired Achilles tendons, although such enhancements were most evident at the 3- to 6-week time points.

CLINICAL RELEVANCE

The inhibition of MMPs at the optimal stage of the repair process may accelerate Achilles tendon repair and improve biomechanical properties, especially when paired with surgical management.

Percutaneous, Minimally Invasive Repair of Traumatic and Simultaneous Rupture of Both Achilles Tendons: A Case Report

Achilles injury is a common musculoskeletal disorder. Bilateral rupture of the Achilles tendon, however, is much less common and usually occurs spontaneously. Complete, traumatic, and bilateral ruptures are rare and typically require long periods of immobilization before the patient can return to full weightbearing. A 52-year-old male was hospitalized for bilateral traumatic rupture to both Achilles tendons. No risk factors for tendon rupture were found. Blood samples revealed no peripheral blood pathologic features. Both tendons were repaired with percutaneous, minimally invasive surgery using the Achillon(®) tendon suture system. Rehabilitation was begun 4 weeks later. An ankle-foot orthosis was prescribed to provide ankle support with an adjustable range of movement, and active plantar flexion was set at 0° to 30°. The patient remained non-weightbearing with the ankle-foot orthosis device and performed active range-of-motion exercises. At 8 weeks after surgery, we recommended that he begin walking with partial weightbearing using a foot-tibial orthosis with the range of motion set to 45° plantar flexion and 15° dorsiflexion. At 10 weeks postoperatively, he was encouraged to return to full weightbearing on both feet. Beginning rehabilitation as soon as possible after minimally invasive surgery, compared with 6 weeks of immobilization after surgery, provided a rapid resumption to full weightbearing. We emphasize the clinical importance of a safe, simple treatment program that can be followed for a patient with damage to the Achilles tendons. To our knowledge, ours is the first report of minimally invasive repair of bilateral simultaneous traumatic rupture of the Achilles tendon.