ANATOMY

Matt Noyes Edwin E. Spencer, Jr.

 

Mean length of the distal biceps insertion is 22 to 24 mm and the mean width is 15 to 19 mm on the proximal radius.

 

 

The biceps tendon inserts like a ribbon on the ulnar aspect of radial tuberosity. Left tendon spirals clockwise, right tendon counterclockwise.12

 

A relatively avascular zone exists just proximal to the tendon insertion site.

 

 

The lacertus fibrosus typically originates from the distal short head of biceps tendon.1

 

NATURAL HISTORY

 

Complete ruptures

 

 

Distal biceps tendon ruptures are most common in the dominant extremity of men in the fourth and sixth decade.

 

Injury typically results from an eccentric muscle contraction. This often occurs when an extension force is applied to the supinated arm in 90 degrees of flexion.

 

The initial pain subsides quickly, but there is usually a noticeable deformity in the anterior brachium as the biceps muscle contracts and retracts. The degree of the retraction can be mitigated by the lacertus fibrosus which may remain intact.

 

The patients usually reports loss of flexion and supination strength. This is especially noted in patients that require repetitive supination such as mechanics and plumbers. Pain is usually not a predominant complaint, although some patients will experience fatigue-type pain and cramping in the retracted muscle belly.

 

 

Studies have revealed a 30% reduction in flexion strength and a 40% loss of supination strength.3,15 Partial ruptures

 

Partial distal biceps tendon injuries are usually more painful than complete tears. Patients usually present with pain in the antecubital fossa especially with resisted flexion and supination. There is an absence of clinical deformity.

 

These can progress to complete tears.

 

Women typically present with partial tears of the distal biceps, usually at a more advanced age (mean age of 63 years).7

 

 

A distinct palpable cystic mass can be found occasionally in women.7 Partial tears are typically from chronic degeneration without acute trauma.

 

Predisposing factors: anabolic steroids, smoking, cubital bursitis, and bony irregularities on bicipital ridge17

 

PHYSICAL FINDINGS

 

In acute cases of a complete distal biceps tendon rupture, there is usually a significant amount of ecchymosis in the antecubital fossa and distal brachium.

 

The distal biceps tendon is easily palpated in the antecubital fossa and lack thereof is confirmed by comparing the involved side to the uninvolved side. Local edema can make the diagnosis a little more difficult; however, the “hook test” has been found to be a very reliable diagnostic tool. To perform the test, the patient actively

 

supinates the forearm while the examiner attempts to “hook” the distal biceps tendon lateral side to medial.16 The hook test has been found to have 100% sensitivity and specificity.16

 

The degree of proximal retraction of the tendon can be mitigated by the lacertus fibrosus.

 

A magnetic resonance imaging (MRI) is usually not necessary to make the diagnosis. However, the only caveat is that if the examiner feels that the distal biceps tendon is intact, then the injury might be more proximal at the myotendinous junction or only a partial tear at its insertion. It is important to make the distinction between the common complete avulsion from the radial tuberosity and an injury at the

myotendinous junction, as the more proximal injuries are best treated nonoperatively.19

 

Partial tears occur at the radial tuberosity and are usually not associated with ecchymosis and demonstrate no proximal retraction. Partial tears present late with pain during resisted flexion and supination. The distal biceps tendon is palpable and frequently tender. An MRI can aid in the diagnosis of partial tendon ruptures.

 

DIFFERENTIAL DIAGNOSIS

Cubital bursitis Elbow dislocation Radial head fracture

Entrapment of lateral antebrachial cutaneous nerve

 

 

NONOPERATIVE MANAGEMENT

 

Nonoperative management of complete distal biceps tendon ruptures entails the use anti-inflammatories and physical therapy to reduce pain and swelling. Patients are allowed to use the extremity as tolerated.

Strengthening should focus on elbow flexion and supination.

 

It should be discussed that complete distal biceps tendon ruptures are not usually associated with residual pain but rather

 

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loss of flexion (30%) and supination (40%) strength.3,15 If that is compatible with the patient's job and lifestyle, then nonoperative management is acceptable.

 

Partial biceps tendon ruptures and ruptures at the myotendinous junction are treated in a similar manner. The patient should proceed to strengthening when full painless range of motion (ROM) is obtained. Operative intervention is considered when nonoperative management fails for partial ruptures. Usually, a minimum 3 to 4 months of observation is appropriate. Patients should be counseled that pain rather than weakness is more of

a predominant complaint with these injuries.

 

SURGICAL MANAGEMENT

Complete and Partial Ruptures

 

The EndoButton (Smith & Nephew, Andover, MA) method of fixation has been shown to have highest ultimate tensile load.14,22 Clinical studies with the EndoButton have also demonstrated good results with few complications.2,6

 

Other methods are suture anchor and interference screw fixation.

 

Chronic Disruptions

 

The definition of “chronic” is vague. Some authors have stated that greater than 8 weeks is chronic and that a graft is needed in these situations. However, the authors have been able to primarily repair distal biceps tendon ruptures out to 3 months. In these situations, the elbow might not extend beyond 60 degrees on the table, but within 3 months after the repair, the patient's ROM is full. The biceps brachii like the pectoralis major has a significant ability to stretch back out over time.

 

The surgeon should discuss with the patient that a more chronic rupture might require a graft and discuss the type of graft to be used. Semitendinosus (either autograft or allograft),23 Achilles tendon allograft18 (with the bone plug inserted into the radial tuberosity or just soft tissue repair), flexor carpi radialis (FCR) autograft,13 and fascia lata9 have been described.

 

Any of the techniques of radial tuberosity fixation described in the acute section can be used. We use the EndoButton for the chronic reconstructions.

 

Positioning

 

The patient is placed in supine position on an arm board with a sterile tourniquet on the upper arm.

 

Approach

Two Incision

 

 

Originally described by Boyd and Anderson,4 a small incision was made in antecubital fossa to identify tendon. A second longitudinal incision is made 1 cm radial to the subcutaneous border of the ulna in the proximal forearm at the level of the biceps tuberosity.

 

Pronation of the forearm when making the second incision protects the posterior interosseous nerve, which is often not visualized.

 

Kelly et al10 modified the approach by using a dorsal approach that split the extensor carpi ulnaris and avoids dissection of supinator to potentially avoid synostosis.

 

May be associated with a higher rate of heterotopic ossification than the single-incision approach

 

Single Incision

 

Initially described as extended S-shaped Henry approach centered over antecubital fossa and has been associated with higher rate of neurologic complications than the two-incision technique.

 

Must maintain supination throughout case to keep posterior interosseous nerve out of surgical field.

 

 

Advent of newer fixation methods has facilitated a safer approach through a limited antecubital fossa incision. Interval between brachioradialis and pronator teres is developed.

 

Must protect lateral antebrachial cutaneous and posterior interosseous nerves by limiting aggressive retraction laterally.

 

May ligate recurrent branch of radial artery to minimize hematoma formation

 

TECHNIQUES

• EndoButton

   

  A longitudinal 4- to 5-cm anterior incision starting at the antecubital fossa and extending distally along the ulnar border of the brachioradialis is used. The lateral antebrachial cutaneous nerve and superficial radial nerve are identified and should be protected.

   

  The distal biceps tendon is retrieved into the wound. This can be accomplished by flexing the elbow and using a retractor to elevate the tissue of the distal brachium anteriorly for exposure. The tendon can be adherent to the adjacent tissues or the lacertus fibrosus. This may require a limited tenolysis to mobilize the tendon stump. Care must be taken to protect and isolate the lateral antebrachial cutaneous nerve and the brachial artery.

   

  On occasion, the biceps tendon is not able to be retrieved through the anterior incision. In that case, an incision can be made medially along the distal aspect of the brachium. The tendon is isolated and prepared and then passed into the distal wound.

   

  Once the tendon is isolated, a no. 2 nonabsorbable suture is woven into the distal biceps tendon using a locking Krackow technique or other locking suture technique. The locking sutures should extend 4 to 5 cm above the stump. The goal is to create a locking stitch proximally and allow about 1 cm of the distal biceps tendon to be unlocked.

   

  The two sutures extending from the tendon stump are then passed through the two central holes of the EndoButton. The sutures are then tied leaving no space between the end of the tendon and the EndoButton. Alternatively, one suture from the tendon can be passed through one of the central holes of the EndoButton and then back through the other central hole, and the knot is then tied, thus placing the knot in between the EndoButton and the tendon stump (TECH FIG 1A). Passing sutures (kite strings) are placed in the other two holes of the EndoButton (TECH FIG 1B).

   

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  TECH FIG 1 • A. EndoButton attached to the distal end of the biceps tendon. B. Passing sutures are placed through the two outer holes of the EndoButton and then passed through a Keith needle for passage through the proximal radius. C. The tendon is pulled into the proximal radial hole as the EndoButton is advanced through the distal hole. D. The EndoButton is flipped to secure it on the other side of the radial cortex.

   

   

  The radial tuberosity is exposed, and a burr is used to create an oval cortical window approximately the same dimension as the distal tendon stump. This is performed while an assistant holds the forearm in full supination. Two small Bennett retractors can be placed on either side of the radial tuberosity. Then, the EndoButton drill is used to create a hole in the far cortex to pass the button.

   

  Keith needles or a Beath needle are used to pass the passing sutures (kite strings) through the bicortical hole and are retrieved as they pass through the skin on the dorsal side of the forearm.

   

  One of the passing sutures is independently pulled, thereby drawing the tendon into the radial tuberosity. Continued tension on this kite string draws the EndoButton in its vertical orientation through the hole in the far cortex of the radius. Once the EndoButton is on the far side of the radius, the other suture is pulled to flip the EndoButton and lock it in its horizontal orientation on the far side of the radius. The authors use fluoroscopy to confirm placement of the button. The passing sutures are then pulled completely out after anatomic tendon placement is visually confirmed (TECH FIG 1C,D).

• Tension Slide Technique

   

  The rationale for development of this technique was to maintain strength of a suspensory cortical button fixation while reducing gap formation at repair site.

   

  Biomechanical studies have proven that tension slide technique (TST) maintains the strength of standard cortical button repair but significantly reduces gap formation and motion at repair site.21

   

  Standard single-incision approach is used for this technique, similar to an EndoButton.

   

  A 3.2-mm drill is used to create a bicortical hole in the radial tuberosity for passing the button. An 8.0-mm cannulated reamer is used to ream the anterior cortex and intramedullary canal to allow for flush seating of tendon. Do not ream bicortically.

   

  The button is placed bicortically on the far cortex of radius and flipped. As suture limbs are tensioned, the tendon is “walked” into the reamed hole.

   

  A 7- × 10-mm interference screw is then inserted on the radial aspect of the hole, pushing the tendon ulnar to mimic the natural anatomy and potentially increase supination strength.

   

  The advantages of TST include the ability to tension the repair from the anterior incision, minimal displacement of tendon after fixation, and no need to predetermine length of suture between tendon and button.20

   

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• Suture Anchor or Interference Screw Fixation

   

  The same anterior approach is used, and the tendon is retrieved in a similar manner with both the suture anchor and interference screw fixation. However, the radial tuberosity is prepared differently.

   

  In the case of interference screw fixation, a hole is drilled in the radial tuberosity. The diameter of the hole depends on the system (and the size of the screw) that is being used.

   

  In the case of suture anchor fixation, the radial tuberosity is lightly decorticated and suture anchors of choice are placed. Some authors have reported using two suture anchors, and most use some kind of a

  sliding knot to advance the tendon onto the bone.8

   

  The disadvantage of this technique is that the tendon is repaired to the surface of the proximal radius instead of into the medullary canal.

• Two-Incision Technique

   

  Anterior incision is made transverse in the antecubital flexion crease and used to locate the distal tendon stump. A second longitudinal incision is made 1 cm radial to the subcutaneous border of the ulna in the proximal forearm at the level of the biceps tuberosity.

   

  Dissection is initially made in the ECU muscle and then through the supinator muscle. Great care is taken to avoid subperiosteal dissection on the ulna.

   

  The forearm is placed in maximal pronation, and an oval cavity is created in the biceps tuberosity with a burr. Three drill holes are then placed anterior to this cavity by slightly supinating the arm.

   

  Two no. 2 FiberWire suture is then placed in the distal tendon in a Krackow technique.

   

  The sutures are then passed from anterior to the posterior incision with long hemostat and retrieved. It is critical to pass the sutures in the interosseous space.

   

  The sutures are then passed through the drill holes and tied over bone with the forearm in supination after drawing the tendon stump into the proximal radius.

• Chronic Distal Biceps Tendon Reconstructions

 

More exposure of the biceps tendon and the myotendinous junction is required for the chronic reconstructions. This can be accomplished by creating a second incision at the medical aspect of the distal brachium. One could connect the two anterior incisions but you risk creating a skin pterygium which could limit extension.

 

A more meticulous dissection is required to protect the lateral antebrachial cutaneous and

musculocutaneous nerves. Invariably, there will be significant scarring and adhesions especially between the biceps tendon and lacertus fibrosus. Some of the lacertus can be used in the reconstruction.

 

 

 

TECH FIG 2 • A. Hamstring tendon is doubled up and folded on itself, and the free ends are passed into the distal end of the biceps tendon stump to add length. The free ends of the tendon graft exit laterally. B. A nonabsorbable suture is placed through the distal end of the graft and used to attach it to the radial tuberosity.

 

 

The authors have used semitendinosus autograft which is harvested in a fashion similar to that used for ACL reconstructions. The tendon is doubled up, and the two free ends are woven into the remaining distal biceps tendon and the myotendinous junction (TECH FIG 2A).

 

A Bunnell tendon passer is very effective at passing the tendon ends.

 

The length of the graft is chosen so that the reconstruction is tight at 60 degrees of elbow flexion. This can be accomplished by fixing it distally first and then performing the weave or vice versa.

 

A nonabsorbable suture is passed through the graft/tendon construct and this is secured to the radial tuberosity (TECH FIG 2B).

 

 

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PEARLS AND PITFALLS

One-incision

technique

• Avoid excessive retraction on the radial side.

• Prepare the biceps tendon prior to the radial tuberosity.

• Maintain maximum supination to protect posterior interosseous nerve.

• If using TST, place interference screw radial to direct tendon toward ulnar aspect of tuberosity for anatomic repair.

Two-incision

technique

• Avoid any subperiosteal dissection or exposure of the ulna.

• Avoid bone tunnel fracture by providing enough space between drill holes.

• Maintain maximum pronation to protect posterior interosseous nerve.

 

 

 

POSTOPERATIVE CARE

 

If an EndoButton or other radiopaque fixation device is used, radiographs are obtained at the time of surgery and at the first postoperative visit to ensure that the fixation is in good position.

 

For the EndoButton repair, the authors remove the splint at 2 weeks and allow active and passive ROM, but no lifting greater than a cup of coffee for 4 weeks. Strengthening is then started but rarely is formal physical therapy necessary.

 

Other authors have reported good results with early ROM therapy.2

 

Others use a more conservative approach and limit full extension until 6 to 8 weeks after surgery. Typical protocol for this therapy approach includes using a hinged elbow brace and increasing extension 10 degree per week until full extension achieved.

 

OUTCOMES

Patient-weighted outcome measures such as the (Disability of the Arm, Shoulder, and Hand) DASH and the Mayo Elbow Performance Score (MEPS) have been used in many studies and have demonstrated excellent results with primary repair.2,8

Objective data including strength testing have also demonstrated good results with anatomic repair especially with regard to restoring supination strength.11

Chronic repairs/reconstructions have also performed well, although the results are not as good as those following acute repair and there is a higher complication rate.23

 

 

COMPLICATIONS

Reruptures are rare in most series, irrespective of the method of fixation.

Certain fixation methods have been associated with a higher occurrence of certain complications.

Classic two-incision technique—heterotopic ossification, radioulnar synostosis, stiffness, and posterior interosseous nerve palsy. Bone tunnel fractures are also unique to the two-incision technique.

Heterotopic ossification and radioulnar synostosis rates have been decreased by avoiding the ulnar periosteum.5,10

Single-incision technique—lateral antebrachial cutaneous (most common) and posterior interosseous nerve palsies, rerupture, stiffness, anterior elbow pain, radioulnar synostosis, and complex regional pain syndrome (CRPS).

 

 

REFERENCES

1. Athwal GS, Steinmann SP, Rispoli DM. The distal biceps tendon: footprint and relevant clinical anatomy. J Hand Surg Am 2007;32(8): 1225-1229.

    

    

2. Bain GI, Prem H, Heptinstall RJ, et al. Repair of distal biceps tendon rupture: a new technique using the

   Endobutton. J Shoulder Elbow Surg 2000;9(2):120-126.

    

    

3. Baker BE, Bierwagen D. Rupture of the distal tendon of the biceps brachii. Operative versus non-operative treatment. J Bone Joint Surg Am 1985;67(3):414-417.

    

    

4. Boyd HB, Anderson DL. A method for reinsertion of the distal biceps brachii tendon. J Bone Joint Surg Am 1961;43(7):1041-1043.

    

    

5. Failla JM, Amadio PC, Morrey BF, et al. Proximal radioulnar synostosis after repair of distal biceps brachii rupture by the two-incision technique. Report of four cases. Clin Orthop Relat Res 1990;(253):133-136.

    

    

6. Greenberg JA, Fernandez JJ, Wang T, et al. EndoButton-assisted repair of distal biceps tendon ruptures. J Shoulder Elbow Surg 2003;12(5):484-490.

    

    

7. Jockel CR, Mulieri PJ, Belsky MR, et al. Distal biceps tendon tears in women. J Shoulder Elbow Surg 2010;19(5):645-650.

    

    

8. John CK, Field LD, Weiss KS, et al. Single-incision repair of acute distal biceps ruptures by use of suture anchors. J Shoulder Elbow Surg 2007;16(1):78-83.

    

    

9. Kaplan FT, Rokito AS, Birdzell MG, et al. Reconstruction of chronic distal biceps tendon rupture with use of fascia lata combined with a ligament augmentation device: a report of 3 cases. J Shoulder Elbow Surg 2002;11(6):633-636.

    

    

10. Kelly EW, Morrey BF, O'Driscoll SW. Complications of repair of the distal biceps tendon with the modified two-incision technique. J Bone Joint Surg Am 2000;82-A(11):1575-1581.

     

     

11. Klonz A, Loitz D, Wöhler P, et al. Rupture of the distal biceps brachii tendon: isokinetic power analysis and complications after anatomic reinsertion compared with fixation to the brachialis muscle. J Shoulder Elbow Surg 2003;12(6):607-611.

     

     

12. Kulshreshtha R, Singh R, Sinha J, et al. Anatomy of the distal biceps brachii tendon and its clinical relevance. Clin Orthop Relat Res 2007;456:117-120.

     

     

13. Levy HJ, Mashoof AA, Morgan D. Repair of chronic ruptures of the distal biceps tendon using flexor carpi radialis tendon graft. Am J Sports Med 2000;28(4):538-540.

     

     

14. Mazzocca AD, Burton KJ, Romeo AA, et al. Biomechanical evaluation of 4 techniques of distal biceps brachii tendon repair. Am J Sports Med 2007;35(2):252-258.

     

     

15. Morrey BF, Askew LJ, An KN, et al. Rupture of the distal tendon of the biceps brachii. A biomechanical study. J Bone Joint Surg Am 1985;67(3):418-421.

     

     

16. O'Driscoll SW, Goncalves LB, Dietz P. The hook test for distal biceps tendon avulsion. Am J Sports Med 2007;35(11):1865-1869.

     

     

17. Safran MR, Graham SM. Distal biceps tendon ruptures: incidence, demographics, and the effect of smoking. Clin Orthop Relat Res 2002;(404):275-283.

     

     

18. Sanchez-Sotelo J, Morrey BF, Adams RA, et al. Reconstruction of chronic ruptures of the distal biceps tendon with use of an achilles tendon allograft. J Bone Joint Surg Am 2002;84-A(6):999-1005.

     

     

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19. Schamblin ML, Safran MR. Injury of the distal biceps at the musculotendinous junction. J Shoulder Elbow Surg 2007;16(2):208-212.

     

     

20. Sethi P, Cunningham J, Miller S, et al. Anatomic repair of the distal biceps tendon using tension slide technique. Tech Shoulder Elbow Surg 2008;9:182-187.

     

     

21. Sethi P, Obopilwe E, Rincon L, et al. Biomechanical evaluation of distal biceps reconstruction with cortical button and interference screw fixation. J Shoulder Elbow Surg 2010;19(1):53-57.

     

     

22. Spang JT, Weinhold PS, Karas SG. A biomechanical comparison of EndoButton versus suture anchor repair of distal biceps tendon injuries. J Shoulder Elbow Surg 2006;15(4):509-514.

     

     

23. Wiley WB, Noble JS, Dulaney TD, et al. Late reconstruction of chronic distal biceps tendon ruptures with a semitendinosus autograft technique. J Shoulder Elbow Surg 2006;15(4):440-444.