The Problem

Distal biceps ruptures have received increased exposure in the literature in recent years, perhaps as a result of increased incidence or a greater understanding of the importance of early diagnosis and management to achieve optimal results. Distal biceps ruptures are estimated to affect 1.2 per 100,000 persons per year. These injuries represent 10% of all biceps injuries. Men are overwhelmingly affected (93% of tears) and generally are between the 4th and 6th decades of life. Women have a tendency to sustain partial tears rather than full-thickness ruptures. These tears generally occur at the insertion site on the radial tuberosity. An association with smoking has been shown in the literature, and anabolic steroid use, hyperparathyroidism, and systemic lupus erythematosus are risk factors. Timely diagnosis and treatment is critical to achieving a successful outcome after rupture.

Clinical Presentation

Patients are generally male, 40-50 years of age and classically present with a history of recent injury in which they experienced eccentric loading of the distal biceps. The dominant elbow is usually affected. They often report an unexpected episode of extension of a flexed elbow often while lifting or carrying a heavy load. This is associated with sudden sharp pain that refers to the antecubital fossa and often a “pop” is felt. However, some patients do not report significant pain or a “pop”. Post-injury ecchymosis may sometimes be noted to be present. A few days later this pain is gradually replaced with a dull ache and weakness. Forearm supination weakness is the usual functional complaint prompting visit to the physician. As the distal biceps contributes a greater percentage to supination strength and then elbow flexion strength, elbow flexion strength may not be a principal source of disability.

Diagnostic Workup

Ecchymosis may be visible over the antecubital fossa if a patient presents acutely, but most patients do not have visible bruising. Proximal retraction of the muscle belly of a completely torn distal biceps may result in a “reverse popeye” deformity, but the degree of retraction at times may be underwhelming if the torn tendon is tethered in the antecubital fossa. They will demonstrate weakness and pain with resisted supination, which can be compared to the contralateral arm, and weakness with elbow flexion to a smaller extent.

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One of the most useful physical examination maneuvers is the Hook Test. This is performed by having the patient abduct the shoulder to 90 degrees and flex the elbow to 90 degrees with full supination of the forearm. When positioned correctly, the palm is then facing the patient. The examiner uses his index finger to “hook” the lateral aspect of the biceps tendon in the antecubital fossa, which will appear cordlike and superficial. A normal result is ability to hook the tendon without causing pain. In cases of complete rupture, the tendon will not be able to be hooked, and in partial tears the tendon may be able to be hooked but will cause pain that will reproduce the patient’s symptoms.

In cases where clinical exam and history are consistent with distal biceps tear, imaging may not be necessary for diagnosis but can be helpful for preoperative planning in determining whether the tear occurred at the insertion site or at the musculotendinous junction (rare) as well as the extent of tendon retraction.

Plain films are often normal but may show some spurring at the radial tuberosity, and rarely a small avulsion of bone can be seen.

Magnetic resonance imaging (MRI) is useful for confirming diagnosis of a tear in cases of a partial tear or identifying another source of pathology in patients with elbow pain and a painless intact hook test such as cubital bursitis, intrasubstance tendinosis, or entrapment of the lateral antebrachial cutaneous nerve. MRI is also useful in delineating the location of the tear and the extent of retraction – especially for chronic cases where allograft augmentation may be necessary. If MRI is contraindicated or not easily performed, ultrasound may be used to confirm tear. For MRI imaging of partial tears, the flexion-abduction-supination (FABS) positioning of the elbow and shoulder allows improved visualization of the course of the tendon near the radial tuberosity.

Non–Operative Management

In patients who are low-demand without functional impairment or are medically unable to safely undergo surgery, non-operative management may be prudent. Tears at the musculotendinous junction are not generally repairable. Partial insertional tears may be treated conservatively, but if pain or weakness persists, then surgical treatment may then be pursued. Patients should be made to understand that with non-operative treatment of a complete tear they may experience a 40-50% loss in supination strength, 30% loss of flexion strength and 15% loss of grip strength compared to pre-injury states. Non-operative treatment consists of supportive treatment such as activity modification, anti-inflammatory medications and physical therapy targeted at range of motion of the elbow and exercises to improve supination and flexion strength.

Indications for Surgery

Operative treatment is recommended for most patients with acute biceps tear and for patients with continued functional limitations in the setting of a chronic injury. Surgical treatment has been shown to be superior to non-operative treatment in improving both supination and flexion strength. Patients with persistently symptomatic partial tears who have failed non-operative treatment may also consider surgical repair.

Surgical Technique

Our preference is a two-incision technique that utilizes a muscle splitting approach of the extensor carpi ulnaris. The muscle splitting approach is a Mayo-modified technique that avoids exposure of the ulna, which decreases the risk of postoperative heterotopic ossification and radioulnar synostosis. It should be noted that this modification is different than the traditional Boyd-Anderson approach which exposed the ulnar periosteum and has a recognized association with heterotopic ossification and radioulnar synostosis postoperatively.

The patient is positioned supine and a hand table is utilized. A nonsterile tourniquet is applied to the proximal arm taking care to ensure that it is proximal enough to allow access to the surgical field after draping. A sterile tourniquet may be useful for chronic tears with severe proximal retraction, but is typically not necessary with acute ruptures. The extremity is then prepped and draped in the usual fashion. An esmarch is used to exsanguinate the extremity and the tourniquet is inflated to 250 mmHg.

An approximately 4 cm transverse incision is made in the antecubital fossa taking care to follow Langer’s lines. Meticulous dissection using bipolar electrocautery is performed to the level of fascia. Care is taken to identify and protect the lateral antebrachial cutaneous nerve, which usually hugs the lateral border of the biceps muscle and tendon (Figure 1). Despite its name, beware that the lateral antebrachial cutaneous nerve may be closer to the midline in the antecubital fossa than you may suspect. In chronic cases where scar tissue has formed around the nerve, a neurolysis is performed and a vessel loop may be placed to protect it throughout the remainder of the procedure. Be careful not to compress this nerve with retractors. The distal biceps tendon will be encountered and if completely torn may be easily dissected off the adjacent fascia (Figure 2). The lacertus is released off the tendon and adhesions are released around the distal stump. The torn stump edge is debrided using scissors taking care not to shorten it. Two #2 nonabsorbable sutures are then passed through the tendon for approximately 2 cm in Krakow fashion. This results in 4 strands of suture available for passage through bone tunnels later in the procedure.

Figure 1.

The lateral antebrachial cutaneous nerve is identified and protected during the anterior dissection. Its position close to the midline at the level of the antecubital fossa must be noted.

Figure 2.

The biceps tendon is isolated and delivered superficially. The distal 3 cm is sutured in a Krackow fashion.

While maintaining the forearm in maximal supination to protect the posterior interosseous nerve (PIN), a large curved Kelly clamp is placed through the antecubital fossa along the medial border of the radius with the curve pointed away from the ulna and pushed towards the skin where it is visible on the dorsal lateral aspect of the proximal forearm. This outlines the position of the posterior incision. The elbow is flexed and a 4 cm incision is made along the dorsal lateral proximal forearm at the location of the tip of the Kelly clamp (Figure 3). This incision should be radial to the subcutaneous border of the ulna. The Kelly clamp is removed and the forearm is maximally pronated in order to protect the PIN during the surgical approach to the radial tuberosity from the dorsal lateral forearm incision. Meticulous dissection is performed to the level of the fascia. The ECU is divided and a small blunt Weitlander retractor may be placed in order to visualize the deep fascia of the supinator. This deep fascia is incised longitudinally. Palpation of the radius at this time while rotating the forearm allows for identification and confirmation of the location of the radial tubersity. The supinator muscle is then split longitudinally directly over the radial tuberosity.

Figure 3.

The dorsal lateral incision is shown here. The use of three small Hohmann retractors in between the radius and ulna can help with visualization of the radial tuberosity. Here the three bone tunnels have been drilled. Of note, the retractor shown superiorly is a right-angle thyroid retractor. Levering retractors such as a baby Hohmann are avoided on this side of the surgical wound, in order to avoid injury to the posterior interosseous nerve.

Our preference is to use 3 baby Hohmans for retraction along the ulnar aspect of the proximal radius; that is, the retractors are placed in between the radius and ulna. On the radial side — the side away from the ulna — we avoid the use of a Hohman or levering-type retractors in order to minimize the risk of injury to the PIN. Instead, we prefer to use thin, blunt, right-angle retractors such as a thyroid retractor or Ragnell on the radial side of the surgical wound. With maximal pronation, the radial tuberosity can be palpated and visualized. The residual biceps stump can then be released off the tuberosity. Visual confirmation is important to avoid confusing the radial head for the radial tuberosity which can happen if the incision was made more proximally than optimal.

With the elbow flexed and maximally pronated, and the radial tuberosity clearly visualizable, a 4.5 mm drill is used to unroof the radial tuberosity in order to create a unicortical docking hole. Bone fragments are removed using dry suction. The radial tuberosity is normally cavernous; therefore, the drill bit should “fall into” the cavernous radial tuberosity when the cortex is opened in unicortical fashion. Do not create a docking hole by excavating bone because this suggests that the drill bit is not located at the anatomic location of the radial tuberosity; meaning that the drill bit is either too proximal or too distal from the radial tuberosity. Our preference is to use a drill bit rather than a motorized burr, since the latter has a tendency to spray small morselized bone fragments throughout the surgical field which may potentially contribute to the formation of postoperative heterotopic ossification.

While the elbow is still flexed, the forearm is slightly supinated from the maximally pronated position. Using a 1.5 mm drill bit, three parallel drill holes 5 mm apart are made approximately 8 mm away from the docking hole. The arm is then extended and the tendon stump and the four strands of sutures are passed from the antecubital fossa down the tract to the radial tuberosity, and then delivered out of the dorsal lateral forearm incision while following the same path of the large curved Kelly clamp that had been used earlier. Among the four strands of sutures on the biceps tendon, the central two sutures are passed through the docking hole and out through the center of the three small drill holes. Each of the remaining sutures is passed through each of the other small drill holes. The distal biceps tendon is then docked into the radial tuberosity and the four strands of sutures are tensioned and tied securely over a bone bridge.

The tourniquet is then deflated. The wounds are closely inspected and any bleeding is managed prior to wound closure. The superficial fascia of the posterolateral incision is repaired with a 2-0 absorbable suture, and then the skin layers of the anterior and posterior wounds are closed in routine subcuticular fashion using fine absorbable sutures. After sterile dressings are placed, the patient is then placed in a well-padded posterior plaster splint with the elbow at 90 degrees of flexion and slight supination. Care is taken during the closure and placement of dressings to avoid forceful passive extension or pronation of the elbow, which places unwanted stress on the repair.

In cases of partial tears, a repair may be performed through a single dorsal lateral incision. By palpating for the radial tuberosity during forearm rotation, the precise location for the incision can be determined in thin patients. If the radial tuberosity is not be palpable, then the incision should be made approximately 2-3 cm distal to the radial head in between the proximal radius and ulna. The surgical dissection is performed with the elbow flexed and forearm supinated as described above. Once the tendon attachment on the bicipital tuberosity is clearly visualized, then it may be fully released from the radial tuberosity. The partial tear typically occurs on the deep portion of the biceps insertion site, so the tear is not visible until the tendon has been released from the radial tuberosity and peeled backward.

Chronic distal biceps are often a result of missed diagnosis or patient delay in seeking care. The complication rates have been reported to increase significantly when repair is attempted after 3 weeks from injury. After 12 weeks, significant tissue retraction, atrophy, and loss of elasticity may not make repair feasible. Additionally, excess scar tissue around neurovascular structures can also make dissection difficult. Interposition grafting in those instances with autograft hamstring, allograft hamstring, or achilles tendon have been described with satisfactory outcomes.

When a chronic distal biceps tendon rupture is not amenable for primary repair, our preference is to us an Achilles tendon allograft for reconstruction. Surgical dissection is performed using the Mayo-modified 2-incision technique described above. If the tendon stump has been retracted proximally significantly such that it is not able to be delivered out of the transverse incision in the antecubital fossa crease, then the incision may be extended proximally from the lateral corner of the transverse incision in order to create an L-shaped incision. If the incision needs to be extended distally, then it is done so from the medial edge of the transverse incision. This is to avoid problems with a thin skin bridge that could be created with the 2nd incision in the dorsal-lateral forearm, if the incision had been extended distally from the lateral edge of the transverse incision. With regard to incorporating the Achilles tendon allograft to the retracted distal biceps tendon stump, our preference is to remove the calcaneal bone block of the Achilles allograft and to suture the “tail” of the Achilles allograft to the musculotendinous junction of the distal biceps. This allows the tendinous portion of the Achilles allograft to be passed from the antecubital fossa to the dorsal lateral forearm incision. The appropriate tension needs to be dialed into the tendon construct and excess tissue resected. Nonabsorbable braided sutures are then passed through the allograft tendon stump, and then it can be docked into the radial tuberosity.

A variant of this technique is to reverse the order of fixation on the radial tuberosity and musculotendinous junction; that is, insert the Achilles allograft into the docking hole on the radial tubersity first and tie the sutures over the bone bridge, and then suture the tail of the Achilles allograft to the musculotendinous junction of the torn and retracted distal biceps. Some surgeons prefer to remove the calcaneal bone block whereas other surgeons prefer to keep the calcaneal bone block intact and to drill two drill holes into it with placement of nonabsorbable sutures through each hole. Proponents of this latter technique indicate that the potential for bone to bone healing within the radial tuberosity may confer an advantage.

In lieu of the docking technique described above, the use of implants have become more popular despite increased costs of additional instrumentation in addition to the implants. Tension-slide techniques using either a button or suture anchor have been described as well as interference screw fixation. When using a suture anchor, the anchor is placed on the radial tuberosity, and then one end of the suture is passed through the tendon stump in Krakow fashion. When the opposite end of the suture is pulled through the suture anchor and tension is applied, then the tendon stump will slide down towards the radial tuberosity; hence, the “tension-slide” technique. When a metal button is used for the tension-slide technique, a nonabsorbable braided suture needs to be passed through the tendon tissue first, and then the ends of the suture need to be passed through the metal button. The sutures need to be passed through the button in a particular manner. One suture limb is passed through a hole #1 in anterograde fashion, and then it is passed through hole #2 in retrograde fashion, the other hole in the button aiming toward the proximal direction. The other suture limb is passed through hole #2 in anterograde fashion, and passed through hole #1 in retrograde fashion. This allows the button to slide when tension is placed on each of the suture limbs in alternating fashion.

Some surgeons prefer to use a single incision technique when using the tension-slide technique, while other surgeons prefer to use one of these implants with a 2-incision surgical approach. The benefit of the 2-incision surgical approach is that the torn tendon is able to be docked into the anatomic footprint of the distal biceps tendon insertion, whereas the 1-incision technique typically allows the tendon to be reattached close to the anatomic attachment site, but not at the precise insertional footprint. In order to “push” the tendon closer to the anatomic attachment site on the radial tuberosity, the tendon may be docked into the radial tuberosity in the typical 1-incision tension slide technique and a tenodesis screw may be placed on the radial side of the docking hole while the forearm is maximally supinated.

For those who prefer to use a single incision approach, a vertical incision may be used distal to the antecubital fossa crease, but a transverse incision along Langer’s lines tends to be more cosmetic. If a transverse incision is used, it should be placed a few centimeters distal to the antecubital fossa crease so that visualization of the radial tuberosity is easier.

Pearls and Pitfalls of Technique

The use of a hand table allows adequate access to the anterior and posterior aspects of the elbow and forearm with extension and flexion of the elbow, respectively.

It is important to position the non-sterile tourniquet as proximally as possible to maximize the sterile field. Paralysis during anesthesia is helpful for decreasing tension while reattaching the biceps tendon.

The two-incision incision technique decreases excessive dissection anteriorly and minimizes iatrogenic injury to the radial nerve. The Mayo modification to the Boyd-Anderson technique minimizes exposure of the ulna, which decreases risk of heterotopic ossification.

It is important to recognize the lateral antebrachial position is close to the midline at the level of the antecubital fossa and to identify and protect it to avoid paresthesias postoperatively.

It is important to avoid excessive debridement of the distal biceps stump to avoid shortening.

When creating the bone tunnels, it is critical to be meticulous in removing any bony debris, which could pose a risk for developing heterotopic ossification.

Potential Complications

Injury to the lateral antebrachial nerve has been described but can be avoided with careful identification and protection including taking care to avoid aggressive retraction. Heterotopic ossification and synostosis presents with pain and loss of motion, particularly supination. This can be identified in early forms on plain films at the 6-week visit, and further localized by a CT scan, which can also guide surgical approach if pain and loss of motion necessitate excision. Rupture of the distal biceps repair is uncommon, but when it occurs, it is often associated with a failure to comply with the post-operative rehabilitation protocol and early weight bearing.

Post–operative Rehabilitation

The patient is initially placed in a well-padded posterior splint in flexion and slight supination and is made non-weight bearing for the first 6 weeks. Wrist and hand exercises are encouraged. The patient is seen in office 7-10 days later and the splint is discontinued at that time. He or she is then placed in a hinged elbow brace. Elbow extension is gradually allowed to increase to full extension over the next 5 weeks. The patient is next seen in the office 6 weeks after surgery and the hinged elbow brace is generally discontinued at that time. Plain films are also taken at this visit to evaluate for presence of any early heterotopic ossification. Full pronation and supination is encouraged. During the following 5 weeks light triceps isotonic exercises are initiated and scapular and rotator cuff, and wrist flexor and extensor strengthening is progressed. Weight bearing is progressed at 1 pound per week. During weeks 10-16, biceps isometric exercises are incorporated. During weeks 16-26 biceps isotonic exercises are initiated. Plyometric exercises are incorporated beginning with two-handed exercises and progressing to one-handed exercises by week 22. Sports or work specific training is incorporated during week 26 with gradual return to normal activity.

Outcomes/Evidence in the Literature

Safran, MR, Graham, SM. “Distal biceps tendon ruptures: Incidence, demographics, and the effect of smoking”. Clin Orthop Relat Res. vol. 404. 2002. pp. 275-283. (Medical records were evaluated over a 5- year period to determine incidence of distal biceps ruptures. This was found to be 1.2 per 100,000 patients per year with the dominant limb affected 86% of the time. A 7.5 times risk of rupture was identified in smokers.)

O’Driscoll, SW, Goncalves, LB, Dietz, P. “The hook test for distal biceps tendon avulsion”. Am J Sports Med. vol. 35. 2007. pp. 1865-1869. (The hook test was described as a clinical exam tool for diagnosing distal biceps tears and was compared to MRI. It was found to have better sensitivity and specificity for diagnosing tears than MRI evaluation.)

Baker, BE, Bierwagen, D. “Rupture of the distal tendon of the biceps brachii. Operative versus non-operative treatment”. J Bone Joint Surg Am. vol. 67. 1985. pp. 414-7. (Cybex testing was used to compare strength in patients with distal biceps who underwent operative versus non-operative treatment. Patients with non-operative treatment showed strength and endurance deficits in elbow flexion and supination when compared to operative treatment.)

Morrey, BF, Askew, LJ, An, KN, Dobyns, JH. “Rupture of the distal tendon of the biceps brachii: A biomechanical study”. JBJS Am. vol. 67. 1985. pp. 418-421. (Immediate attachment, delayed attachment, and conservative management were studied in patients with rupture of the distal biceps. Elbow supination strength was reduced by 50% and flexion strength was decreased by an average of 30% with conservative treatment. Early reattachment restored flexion and supination strength at one year. Delayed attachment improved strength but did not restore it to normal levels.)

Boyd, HB, Anderson, LD. “A method for reinsertion of the distal biceps brachii tendon”. JBJS Am. vol. 43. 1961. pp. 1041-1043. (The original two- incision technique was described by Boyd and Anderson, which involved periosteal exposure of the ulna.)

Kelly, EW, Morrey, BF, O’Driscoll, SW. “Complications of repair of the distal biceps tendon with the modified two-incision technique”. JBJS Am 200. vol. 82. pp. 1575-1581. (A modification to the Boyd-Anderson technique was described whereby the extensor carpi ulnaris was split and the ulnar exposure and supinator dissection was avoided. In a series of 78 patients over 8 years, no patient developed radioulnar synostosis.)

El-Hawary, R, Macdermid, JC, Faber, KJ, Patterson, SD, King, GJ. “Distal biceps tendon repair: Comparison of surgical techniques”. J Hand Surg Am. vol. 28. 2003. pp. 496-502. (Patients undergoing single anterior incision versus two-incision technique for distal biceps repaired were compared over a 4- year period. There was a 44% rate of complications in the one- incision group compared to 10% in the two-incision group. Most complications were lateral antebrachial cutaneous nerve paresthesias in the one-incision group. In the two-incision group there was a single transient superficial radial nerve paresthesia.)

Wysocki, RW, Cohen, MS. “Radioulnar heterotopic ossification after distal biceps tendon repair: Results following surgical resection”. J Hand Surg Am. vol. 32. 2007. pp. 1230-1236. (Patients treated with heterotopic ossification (HO) resection after distal biceps repair were compared to patients who had undergone distal biceps repair that was uncomplicated. The HO group did not show a statistically significant difference in arc of range of motion or Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire (American Academy of Orthopaedic Surgeons, Rosemont, IL) score when compared to the uncomplicated group.)

Hang, DW, Bach, BR, Bojchuk, J. “Repair of chronic distal biceps brachii tendon rupture using free autogenous semitendinosus tendon”. Clin Orthop. vol. 323. 1996. pp. 188-191. (A technique utilizing an autogenous semitendinosus graft for chronic distal biceps rupture was outlined. Its similarity in caliber to the native biceps tendon makes it amenable for use as a graft in the chronic setting. In a patient treated 1 year after injury, Hang et al found only 13% flexion and 14% supination deficit.)

Sanchez-Sotelo, J, Morrey, BF, Adams, RA, O’Driscoll, SW. “Reconstruction of chronic ruptures of the distal biceps tendon with use of an achilles tendon allograft”. J Bone Joint Surg Am. vol. 84-A. 2002. pp. 999-1005. (Achilles tendon allograft was used to successfully reconstruct chronic distal biceps tendon ruptures in 4 patients with an average follow-up of 2.8 years. All four patients had satisfactory subjective outcomes, full range of motion, and excellent Mayo Elbow Performance Scores.)

Leighton, MM, Bush-Joseph, CA, Bach, BR. “Distal biceps brachii repair: Results in dominant and nondominant extremities”. Clin Orthop. vol. 317. 1995. pp. 114-12. (Patients undergoing a two-incision technique for repair of the distal biceps in their dominant and non-dominant arm were followed at an average of 30 months after surgery. Those with injury to the dominant arm had full return of supination and flexion strength whereas those with injury to the non-dominant arm had a 14% loss of supination and flexion strength.)


Distal biceps ruptures account for 10% of all biceps ruptures. Men, between 40-60 years of age are most commonly affected on their dominant arm. The injury most commonly occurs at the insertion site on the radial tuberosity. The immediate injury can be associated with a sudden “pop” with pain in the antecubital fossa and dorsolateral forearm but the patient’s primary complaint is generally loss of supination strength. The hook test is very useful for identifying complete and partial tears and an MRI can be helpful in confirming diagnosis.

Partial tears can be initially treated conservatively with gradual return to normal activities. However, the recommendation is early treatment of acute full thickness distal biceps tears. Patients should be counseled that non-operative treatment of distal biceps tears is associated with a 30% decrease in elbow flexion strength and up to 50% decrease in supination strength.

While a two-incision technique has been associated with increased risk of synostosis, this risk is minimized by utilizing a dorsal muscle- splitting approach and avoiding exposure of the ulnar periosteum. Use of a drill to create the docking site and bone tunnels with careful removal of debris with copious irrigation may also minimize this risk. Identification and protection of the lateral antebrachial nerve is critical. Close adherence to the post-operative rehabilitation protocol is important, particularly gradual progression to full extension and weight bearing.