Emerging Insights On Percutaneous Repair Of The Achilles Tendon Rupture

The Achilles tendon is the largest and strongest tendon in the human body. Increased interest in physical fitness and athletic activity by young, middle-aged, and older patients has led to a higher incidence of rupture.¹ Surgical correction is often the treatment of choice because it offers less immobilization time, early weightbearing, better rehab potential, lower risk for re-rupture and faster recovery with return to activity.²    Achilles tendon ruptures can take place at any point during a patient’s lifetime but most commonly happen between the ages of 30 and 50.³ It is five times more likely in men and occurs 75 percent of the time 2 to 6 cm proximal to the insertion into the calcaneus.⁴ They are usually the result of an indirect injury but clinicians have described other mechanisms.    Although rare, direct trauma such as lacerations, crushing injuries or direct blows to the posterior leg can cause disruption of the tendon. Researchers have described intrinsic degeneration from chronic tendonitis or tendinosis in up to 10 percent of cases.^5,6 Research has also implicated the use of fluoroquinolone antibiotics and corticosteroids in placing patients at a higher risk for rupture.⁴    Indirect mechanisms are by far the most common reasons for Achilles tendon ruptures and usually involve a rapid loading moment on an already tensed tendon. A frequent mechanism in the non-athlete is an abrupt and unexpected dorsiflexion force to the ankle combined with a strong contraction of the muscle unit. Examples of this would be stepping off a curb wrong, unexpectedly stepping into a hole or misjudging the dismount off a ladder. A common mechanism in the athlete is pushing off a planted foot while the knee is extended. This often occurs with tennis or racquetball players who lunge for a ball. Another common mechanism is a violent dorsiflexion moment on a plantarflexed ankle. One can see this with jumping from a height or in a gymnast doing a tumbling run.⁷

Pertinent Anatomical Insights

The Achilles tendon is a conjoined tendon formed from the gastrocnemius and soleus muscles (triceps surae). The tendon rotates 30 to 150 degrees before it inserts onto the posterior aspect of the calcaneus. There is a thin paratenon surrounding the tendon that is susceptible to damage during a rupture.⁸    The blood is supplied mostly from the posterior tibial artery feeding the gastrocnemius and soleus muscles. The tendon feeds directly from the myotendinous junction, mesosternal vessels, paratenon, and the bone-tendon junction at the insertion into the calcaneus. The “watershed” area is located 2 to 6 cm proximal to the insertion and this is where most ruptures occur. Researchers have shown that the “watershed” area has a diminished blood supply relative to the rest of the tendon that worsens with age.⁹    The sural nerve courses along the lateral aspect of the Achilles tendon and is anterolateral to the short saphenous vein. It is susceptible to damage during the initial injury and with the surgical repair process.    The plantaris arises close to the lateral head of the gastrocnemius muscle. It forms a long, slender tendon that runs along the medial aspect of the Achilles. It is absent 7 percent of the time and is frequently damaged during an Achilles rupture.⁸ When the plantaris is present, one can use it to help augment the repair.

Keys To The Patient History And Physical Exam

Patients will often describe a loud pop or snap that coincides with one of the aforementioned mechanisms. There is usually a sudden, sharp pain that feels like they were kicked in the back of the leg or struck with an object. One of my favorite accounts is from a patient who was playing mixed doubles tennis with his wife. He was lunging for a ball at the net, felt a pop and his first thought as he fell to the ground was that his wife had hit him in the back of the leg with her racket.    Patients are usually able to walk with a limp after the injury but have significant weakness and difficulties with coordination. The pain level typically becomes very tolerable after a day or two, and diminishes to a dull ache.    Edema and ecchymosis are often present on the physical exam. There is usually a visual dell and palpable gap between the two ends of tendon. This is not always present in partial tears and not easily appreciated when there is excessive edema. The posterior aspect of the calcaneus will appear to be more prominent than the contralateral heel. There is often some plantarflexion power available from the recruitment of other muscles, an intact plantaris or partial tear, but the patient is rarely able to stand on his or her toes. These patients will also have hyperdorsiflexion in comparison to the uninjured side.    One performs the Thompson test with the patient lying in the prone position.¹⁰ Squeeze the calf of the injured leg and observe the foot. A positive Thompson test occurs when there is no passive plantarflexion of the foot or it is significantly less than the contralateral foot. This is indicative of a rupture. A negative Thompson test occurs when there is passive plantarflexion of the foot. This does not always rule out a rupture because a partial tear can still give a false negative.    Clinicians should take radiographs at the initial exam to rule out osseous pathology. This will sometimes show a disruption in Kager’s triangle or irregularities in the radiographic shadow of the Achilles tendon, but these are of little clinical value in guiding treatment. Ultrasound evaluation is a useful study that clinicians can do quickly and inexpensively in the office. Researchers have shown that ultrasound evaluation is 72 percent to 94 percent sensitive and 83 percent to 100 percent specific for Achilles tendon ruptures.¹¹ Magnetic resonance imaging (MRI) is the gold standard for evaluating the tendon but one does not need to do this on a regular basis.¹² I only order these if the diagnosis is not obvious, there is a complex or unusual tear, a re-rupture, or if there has been a significant time lapse between the injury and presentation in clinic.

Recognizing The Drawbacks Of Conservative Treatment

Conservative treatment remains a viable treatment option for Achilles ruptures. However, there are several drawbacks, making conservative treatment less desirable for active and athletic patients. It requires extended immobilization in a cast or boot with prolonged rehab. It is often difficult to get anatomic tension on the tendon, which can leave the patient with a lengthened Achilles leading to triceps surae weakness and calf fatigue. The biggest and most concerning complication is re-rupturing, occurring in an average of 18 percent of cases.^13,14

A Shift Toward Percutaneous Mini-Open Techniques

Traditional open Achilles repair techniques have proven very effective but are not without drawbacks including adhesions, sural nerve entrapment or injury, wound healing complications and infections.¹⁵ This has led to the development of less invasive or percutaneous repair techniques that offer potential solutions for these problems.    Early percutaneous techniques frequently brought complications including a 16.7 percent incidence of sural nerve entrapment.¹⁶ Newer mini-open techniques have emerged to eliminate these problems. Studies have shown minimal wound and nerve complications, and an early return to full weightbearing and athletic activity.¹⁷ Henriquez compared this technique to a traditional open repair and concluded that it provides function similar to that achieved with open repair, a better cosmetic appearance, a lower rate of wound complications, and no apparent increase in the risk of rerupture.¹⁸

Step-By-Step Insights On The Technique

One would perform the procedure with the patient prone under general anesthesia. The addition of a popliteal block for postoperative analgesia is per the surgeon’s preference. The surgeon may have the contralateral limb prepped to compare Achilles tension and foot position, but this does not routinely happen. Use a thigh tourniquet for hemostasis. Several systems have been designed to help facilitate a mini-open technique. I prefer the Percutaneous Achilles Repair System (PARS, Arthrex).    Make a 3 cm transverse incision over the rupture site, close to the proximal stump and carry it down to the paratenon. Be sure to identify and protect the sural nerve. Open the paratenon transversely and identify the tendon ends. Debride non-viable tendon portions, remove clot material and irrigate the site. Alternatively, the surgeon can use a small linear incision if he or she feels it may be necessary to convert to a standard open technique. Surgeons may also want to use this approach initially until they are comfortable with the small incision.    Grasp the proximal tendon end with an Allis clamp and bring it to the wound margin. You may need to grasp this several centimeters from the rupture in order to get a good hold on it. Release any adhesions that have formed between the tendon and paratenon in order to allow the PARS jig to insert more freely. These are more prevalent in older ruptures. To date, I have been able to use this technique successfully on ruptures as old as four weeks.    Proceed to insert the PARS jig with the inner arms between the tendon and paratenon. The arms adjust outward and the surgeon should widen them as he or she advances the jig proximally. The muscle belly will usually stop the jig at the appropriate level. Maintain tension on the tendon with the Allis clamp to facilitate this maneuver.    One can pass sutures through the tendon in a variety of patterns using guide pins with suture passing loops that one inserts into pre-numbered holes in the PARS jig. The jig has seven numbered slots that are angled to allow transverse and crossed orientation of the suture within the tendon. A total of three sutures typically remain within the tendon and are color coded. Surgeons most frequently utilize the first five slots, using two to facilitate a crossing locking stitch and an additional two slots are available if one feels the need for a stronger repair.    Once the surgeon has passed the sutures, he or she can withdraw the jig, pulling the suture out the small incision. The sutures now lie on the medial and lateral aspects of the tendon between it and the paratenon. One can tug them as a unit to ensure good purchase and distal movement of the tendon. Proceed to lock the middle (blue) suture and cross it back through the tendon on both sides by wrapping around the passing suture and through the loop on its end. This allows you to lock the suture within the body of the tendon in a crossed manner for additional strength and stability.    Repeat the same steps on the distal portion of the rupture. Then plantarflex the foot into a similar position as the contralateral foot and tie the two closest sutures (black and white stripes) together, bringing the tendon ends together and tensioning them. Proceed to tie the middle (blue) locking sutures and then tie the farthest (white) sutures. The surgeon can augment the repair with absorbable suture before closing the paratenon, subcutaneous layer and skin.

Facilitating Post-Op Care And A Progression To Activities

Apply a well-padded posterior splint with the foot in plantarflexion. The patient remains non-weightbearing in this position for two weeks and transitions into protected weightbearing in an Achilles boot, removing wedges incrementally. Range of motion (ROM) exercises start at two weeks with subsequent formal rehabilitation starting at six weeks. Most patients are able to use an exercise bike on low resistance at six to eight weeks and can return to athletic activity at six months.

In Conclusion

With an increased prevalence of Achilles rupture in our active population and the patient’s desire to return quickly and at a high level, surgical repair remains the gold standard of treatment. Traditional open techniques are very effective but leave the patient open to complications and slow recovery.    The aforementioned percutaneous technique is becoming the norm in the hands of sports medicine surgeons because of its ease of use, shorter OR time, lower risk, faster recovery and better appearance. I have been using this technique in non-complicated ruptures for nearly two years and can report a high satisfaction rate and no wound healing problems, sural nerve damage or re-rupture.    Dr. Schroeder is a Fellow of the American College of Foot and Ankle Surgeons. He is board-certified in foot surgery and reconstructive rearfoot and ankle surgery. Dr. Schroeder is in private practice with Sports Medicine Oregon in Tigard, OR and is the foot and ankle surgeon for the Portland Timbers, Thorns, and Thunder. References 1. Clayton R, Court-Brown C. The epidemiology of musculosk-skeletal tendinous and ligamentous injuries. Injury. 2008;39(12):1338–1344. 2. Patel VC, Lozano-Calderon S, McWilliam J. Immediate weight bearing after modified percutaneous Achilles tendon repair. Foot Ankle Int. 2012;33(12):1093–1097. 3. Nillius SA, Nilsson BE, Westlin NE. The incidence of Achilles tendon rupture. Acta Orthop Scand. 1976;47(1):118–121. 4. Maffulli N, Longo UG, Maffulli GD, Khanna A, Denaro V. Achilles tendon ruptures in elite athletes. Foot Ankle Int. 2011;32(1):9-15. 5. Inglis AE, Scott WN, Sculco TP, Patterson AH. Ruptures of the tendo achillis: An objective assessment of surgical and non-surgical treatment. J Bone Joint Surg Am. 1976; 58(7):990–993. 6. Schepsis AA, Jones H, Haas AL. Achilles tendon disorders in athletes. Am J Sports Med. 2002;30(2):287-305. 7. Khan RJ, Fick D, Keogh A, Crawford J, Brammar T, Parker M. Treatment of acute Achilles tendon ruptures. A meta-analysis of randomized, controlled trials. J Bone Joint Surg Am. 2005;87(10):2202-10. 8. Sarrafian’s Anatomy of the Foot and Ankle, 3rd ed. Lippincott, Williams & Wilkins, Philadelphia, 2011. 9. Astrom M, Westlin N. Blood flow in human Achilles tendon assessed by laser Doppler flowmetry. J Orthop Res. 1994;12:246–252. 10. Thompson TC, Doherty JH. Spontaneous rupture of tendon of Achilles: A new clinical diagnostic test. J Trauma. 1962; 2:126–129. 11. Kalebo P, Allenmark C, Peterson L, Sward L. Diagnostic value of ultrasonography in partial rupture of the Achilles tendon. Am J Sports Med. 1992;20(4):378–381. 12. Khan KM, Forster BB, Robinson J, et al. Are ultrasound and magnetic resonance imaging of value in assessment of Achilles tendon disorders? A two year prospective study. Br J Sports Med. 2003; 37(2):149–153. 13. Twaddle BC, Poon P. Early motion for Achilles tendon ruptures: is surgery important? A randomized, prospective study. Am J Sports Med. 2007;35(12):2033-8. 14. Moller M, Movin T, Granhed H, Lind K, Faxen E, Karlsson J. Acute rupture of tendon Achilles. A prospective randomised study of comparison between surgical and non-surgical treatment. J Bone Joint Surg Br. 2001;83(6):843–848. 15. Cetti R, Christenen SE, Ejsted R, Jensen NM, Jorgensen U. Operative versus non-operative treatment of Achilles tendon rupture. A prospective randomized study and review of the literature. Am J Sports Med. 1993; 21(6):791–799. 16. Elliot RR, Calder JD. Percutaneous and mini-open repair of acute Achilles tendon rupture. Foot Ankle Clin. 2007;12(4):573-82. 17. Assal M, Jung M, Stern R, Rippstein P, Delmi M, Hoffmeyer P. Limited open repair of Achilles tendon ruptures: A technique with a new instrument and findings of a prospective multicenter study. J Bone Joint Surg Am. 2002;84(2):161–170. 18. Henriquez H, Munoz R, Carcuro G, Bastias C. Is percutaneous repair better than open repair in acute Achilles tendon rupture? Clin Orthop Relat Res. 2012;470(4):998-1003.