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Tendon graft harvesting techniques
TENDON GRAFT HARVESTING TECHNIQUES MARWAN A. WEHBI~, MD
Tendon grafts can be safely harvested from both the upper and lower limb. Harvesting techniques to produce a tendon graft of appropriate length and width for any given operation are described. KEY WORD: tendon graft
Any tendon h a ~ e s t e d for grafting must not result in a functional loss at the donor site. A tendon must therefore be expendable or should have a "back-up" tendon to take over its function. Furthermore, for any tendon to be eligible for harvesting there can be no significant anomaly in either the donor tendon or its back-up! Potential donor tendons from the upper limb include the extensor indicis (EIP), extensor digiti minimi (EDM) and palmaris longus (PL). The flexor digitorum superficialis tendon should be used only as a last resort, because of its importance in finger balance, dexterity, and strength. From the lower limb, the plantaris and second long toe extensor are the tendons of choice.
PREOPERATIVE EVALUATION The anticipated needs in a tendon graft should be determined; the needed length and strength of tendon graft can be estimated. For example, the tendon material needed for an oblique retinacular ligament reconstruction is very different from that needed for flexor profundus reconstruction of a long finger. A survey of potential donor tendons should be made through history and physical examination. A previously injured tendon would not make a good tendon graft, and an absent PL tendon also is not a likely candidate for harvesting.
of the extensor retinaculurn. At that level, the EIP musculotendinous junction can be seen in the fourth dorsal compartment, deep to the extensor digiti (EDC) tendons. The EIP tendon is retrieved from the proximal incision and divided. If any difficulty is encountered in retrieving the tendon, this is probably caused by an aberrant insertion that can be seen and divided through an intermediate incision at the distal edge of the retinaculum.
EXTENSOR DIGITI MINIMI The EDM tendon can be used in 50% of~hands, w h e n there is an adequate EDC tendon to replace its function. A transverse incision is performed at the MP joint of the little finger and the anatomy of the extensors in that area is ascertained. The presence of a tendinous junctura C is a prerequisite to proceeding any further with the dissection. 1 The contribution of the extensor digitorum tendon is preserved and both slips of the extensor minimi are tagged with a 4-0 silk suture, then divided. A second incision is performed proximal to the radioulnar joint and the extensor minimi musculotendinous junction is identified by tugging on the silk suture (Fig 1). If any difficulty is encountered in retrieving the tendon proximally, a third intermediate incision is performed to check and divide any aberrant insertions. In the alternative, only one of the slips of the EDM tendon may be harvested. 2
EXTENSOR INDIClS (PROPRIUS) The initial incision is performed at metacarpophalangeal (MP) joint level (Fig 1). The EIP tendon is identified, ulnar to the extensor digitorum tendon and deep to junctura A. 1 A 4-0 silk suture is used as a "handle" on the tendon, which is then divided as it joins the dorsal hood, just proximal to the sagittal bands. A second incision is performed ulnar to Lister's tubercle, at the proximal edge From the Pennsylvania Hand Center, Bryn Mawr, and Thomas Jefferson University, Philadelphia, PA. Address reprint requests to Marwan A. WehbG MD, Pennsylvania Hand Center, Reprints Department, PO Box 241, Bryn Mawr, PA 19019. Copyright 9 1993 by W. B. Saunders Company 1048-6666/93/0304-0006505.00/0
EIP
Fig 1. Incisions used to harvest tendon grafts from the hand and forearm,
Operative Techniques in Orthopaedics, Vol 3, No 4 (October), 1993: pp 293~
293
incision if there is a need to avoid the stigma of a "suicidal scar" (Fig 1). The tendon is identified, tagged, and divided. A Brand tendon stripper (Baxter Healthcare, American V. Mueller Division, Niles, IL) can facilitate the harvest a great deal at this point. 3 Attachments of the tendon to forearm fascia are divided, then the tendon is threaded through the stripper (Fig 3A). Firm traction on the tendon is maintained while the stripper is advanced proximally in a back-and-forth rotary fashion (Fig 3B). The stripper should be held parallel to the axis of the forearm, toward the medial humeral epicondyle, to avoid transecting the tendon in midsubstance. After the tendon is obtained, the stripper is pulled out with the same gentle rotary motion.
Fig 2. The presence of a PL tendon can usually be ascertained by physical examination by touching the thumb to the tip of the little finger and flexing the wrist against resistance.
PALMARIS LONGUS This is perhaps the only expendable tendon that could be delineated preoperatively by palpation with the wrist flexed and thumb touching the tip of the little finger (Fig 2). The PL may be harvested through a transverse incision proximal to the wrist flexion crease or through an oblique
PLANTARIS When present, this tendon is consistently anterior to the Achilles tendon at its insertion in the calcaneus. A longitudinal incision is performed posterior to the medial malleolus (Fig 4A). The plantaris tendon is identified, divided, and tagged. Its loose adhesions to surrounding tissues are divided, and the tendon is retrieved with a long Brand stripper in a similar fashion as for the palmaris tendon (Fig 4B). It is important to point the stripper toward the lateral aspect of the knee joint, because the origin of the plantaris muscle is located in that area.
i ~-, ,: ,~.: , .,: .-. ,r-. i,~:.;;,,~-,:,~,,;.-,~.~- ~ c : : , ~ , r ~ i . : , : ~ ~ T , ~ i , , L v ' : ~
Fig 3. Harvest of a PL tendon with a Brand stripper. (A) The tagged tendon is threaded through the stripper. (B) The tendon is grasped with a small Kocher hemostat, and held taut, while the stripper is advanced with a rotary motion. (C) The tendon is retrieved with some muscle fibers attached.
294
MARWAN
A. W E H B E
A
Incision for
Second Toe Extensor
Fig 4. Incisions used to harvest tendon grafts from the lower extremity. (B) A long Brand stripper is used to harvest the plantaris and toe extensor tendons.
A
Fig 5. (A) Harvest of long toe extensor tendon. The second toe is the longest and most medial of this tendon mass. (B) Additional incisions may be necessary to free-up the second toe extensor proximally.
295
Fig 6. Portion of the abductor pollicis Iongus tendon can be harvested for use when doing a trapezium tendon Interposition arthroplasty (Anchovy). (A) The tendon dissection is started with a scalpel or mini-meniscotome. (B) A Brand stripper may be used to complete the harvest. (C) A significant length of tendon may be obtained without Interfering with thumb function.
LONG TOE EXTENSORS
LOCAL TENDONS
The long extensor of the second toe is the most easily harvested tendon of the toe extensors because of its position at the edge of the common long toe extensor tendon (Fig 5A). It can provide a substantial tendon graft. Its dissection is made difficult by the intervening extensor retinaculum, and the need to split it from the remaining tendon mass; however, this is facilitated by the use of a long tendon stripper (Fig 5B). A supplementary incision frequently has to be made proximal to the extensor retinaculum to complete the tendon harvesting (Fig 4A). The extensor digitorum brevis tendon is located lateral to the longus tendon at the insertion in the toe, and can be easily dissected out and preserved. The patient should be warned against the possibility of weak toe extension.
Up to 60% of the surface of a tendon can be harvested without weakening the tendon. 4 Usually, no separate incision is needed for this type of graft. The selected tendon insertion is identified and up to 50% of its substance is isolated for harvesting (Fig 6). This is typically obtained from the extensor carpi radialis or abductor pollicis longus tendons. The tendon is split longitudinally and proximally, the use of a "mini-meniscectomy" knife or a Bunnell or Brand stripper can facilitate that harvest (Fig 7). A separate proximal incision may be needed to divide the harvested portion of the tendon with minimal injury to the donor muscle.
GENERAL CONSIDERATIONS
Fig 7. Instruments used to harvest tendons for grafting: Brand stripper, Bunnell stripper, and Beaver mini-meniscotome. 296
Tendons in the upper limb can provide a graft length of 13 to 16 cm (rarely up to 19 cm), with a width of 3 mm. s'6 From the lower limb, a tendon graft measuring 35 cm in length can be commonly obtained; however, the usual width is 2 to 2.5 mm. 6 A wider graft can generally be obtained from the long second toe extensor. It is not clear what the optimal tendon width is for any particular application; however, tensile strength is related to crosssectional area. s A 2-mm tendon graft may not have the necessary strength to withstand the stresses applied on a profundus tendon. It should also be noted that the PL tendon may be absent in 25% of upper limbs, and in both limbs of 5% of people. If an upper extremity is found to be missing a MARWAN A. WEHBE
PL, there is a 28% chance of its being absent 6n the o t h e r side as well. T h e plantaris t e n d o n is absent in 19% of lower limbs, a n d in both lower limbs of 4% of people. If a lower extremity is f o u n d with no plantaris t e n d o n , the contralateral side will be deficient as well in 44% of people. 6 A Brand t e n d o n stripper 2 can greatly facilitate the harvest for all t e n d o n s discussed here. Varying degrees of preliminary dissection will be required, in particular for tendons that travel u n d e r n e a t h the extensor r e t i n a c u l u m of the wrist or ankle. A t e n d o n graft is u s e d to replace a portion of a t e n d o n that has b e e n d a m a g e d or resected, and occasionally as a substitute for a ligament. These conditions are usually self-limiting, so a d o n o r site s h o u l d be selected that
TENDON GRAFTING
would not cause a greater handicap than the problem being treated.
REFERENCES 1. Wehb6MA: Junctura tendinum. J Hand Surg [Am] 17:1124-1129,1992 2. Snow IW: Ulnar half of extensor digiti quinti proprius tendon for flexor grafts. Plast Reconstr Surg 42:603-604, 1968 3. Brand PW: Tendon grafting. J Bone Joint Surg [Br] 43:444-453, 1961 4. Cooney WP, Weidman KA, Malo DS, et al: Partial flexor tendon lacerations, in Hunter JM, Schneider LH, Mackin EJ (eds). Tendon Surgery in the Hand. St Louis, MO, Mosby, 1987, pp 148-155 5. Carlson GD, Botte MJ, Josephs MS, et al: Morphologic and biomechanical comparison of tendons used as free grafts. J Hand Surg [Am] 18:76-82, 1993 6. Wehb6 MA: Tendon graft donor sites. J Hand Surg [Am] 17:11301132, 1992
297
Tendon grafts can be safely harvested from both the upper and lower limb. Harvesting techniques to produce a tendon graft of appropriate length and width for any given operation are described. KEY WORD: tendon graft
Any tendon h a ~ e s t e d for grafting must not result in a functional loss at the donor site. A tendon must therefore be expendable or should have a "back-up" tendon to take over its function. Furthermore, for any tendon to be eligible for harvesting there can be no significant anomaly in either the donor tendon or its back-up! Potential donor tendons from the upper limb include the extensor indicis (EIP), extensor digiti minimi (EDM) and palmaris longus (PL). The flexor digitorum superficialis tendon should be used only as a last resort, because of its importance in finger balance, dexterity, and strength. From the lower limb, the plantaris and second long toe extensor are the tendons of choice.
PREOPERATIVE EVALUATION The anticipated needs in a tendon graft should be determined; the needed length and strength of tendon graft can be estimated. For example, the tendon material needed for an oblique retinacular ligament reconstruction is very different from that needed for flexor profundus reconstruction of a long finger. A survey of potential donor tendons should be made through history and physical examination. A previously injured tendon would not make a good tendon graft, and an absent PL tendon also is not a likely candidate for harvesting.
of the extensor retinaculurn. At that level, the EIP musculotendinous junction can be seen in the fourth dorsal compartment, deep to the extensor digiti (EDC) tendons. The EIP tendon is retrieved from the proximal incision and divided. If any difficulty is encountered in retrieving the tendon, this is probably caused by an aberrant insertion that can be seen and divided through an intermediate incision at the distal edge of the retinaculum.
EXTENSOR DIGITI MINIMI The EDM tendon can be used in 50% of~hands, w h e n there is an adequate EDC tendon to replace its function. A transverse incision is performed at the MP joint of the little finger and the anatomy of the extensors in that area is ascertained. The presence of a tendinous junctura C is a prerequisite to proceeding any further with the dissection. 1 The contribution of the extensor digitorum tendon is preserved and both slips of the extensor minimi are tagged with a 4-0 silk suture, then divided. A second incision is performed proximal to the radioulnar joint and the extensor minimi musculotendinous junction is identified by tugging on the silk suture (Fig 1). If any difficulty is encountered in retrieving the tendon proximally, a third intermediate incision is performed to check and divide any aberrant insertions. In the alternative, only one of the slips of the EDM tendon may be harvested. 2
EXTENSOR INDIClS (PROPRIUS) The initial incision is performed at metacarpophalangeal (MP) joint level (Fig 1). The EIP tendon is identified, ulnar to the extensor digitorum tendon and deep to junctura A. 1 A 4-0 silk suture is used as a "handle" on the tendon, which is then divided as it joins the dorsal hood, just proximal to the sagittal bands. A second incision is performed ulnar to Lister's tubercle, at the proximal edge From the Pennsylvania Hand Center, Bryn Mawr, and Thomas Jefferson University, Philadelphia, PA. Address reprint requests to Marwan A. WehbG MD, Pennsylvania Hand Center, Reprints Department, PO Box 241, Bryn Mawr, PA 19019. Copyright 9 1993 by W. B. Saunders Company 1048-6666/93/0304-0006505.00/0
EIP
Fig 1. Incisions used to harvest tendon grafts from the hand and forearm,
Operative Techniques in Orthopaedics, Vol 3, No 4 (October), 1993: pp 293~
293
incision if there is a need to avoid the stigma of a "suicidal scar" (Fig 1). The tendon is identified, tagged, and divided. A Brand tendon stripper (Baxter Healthcare, American V. Mueller Division, Niles, IL) can facilitate the harvest a great deal at this point. 3 Attachments of the tendon to forearm fascia are divided, then the tendon is threaded through the stripper (Fig 3A). Firm traction on the tendon is maintained while the stripper is advanced proximally in a back-and-forth rotary fashion (Fig 3B). The stripper should be held parallel to the axis of the forearm, toward the medial humeral epicondyle, to avoid transecting the tendon in midsubstance. After the tendon is obtained, the stripper is pulled out with the same gentle rotary motion.
Fig 2. The presence of a PL tendon can usually be ascertained by physical examination by touching the thumb to the tip of the little finger and flexing the wrist against resistance.
PALMARIS LONGUS This is perhaps the only expendable tendon that could be delineated preoperatively by palpation with the wrist flexed and thumb touching the tip of the little finger (Fig 2). The PL may be harvested through a transverse incision proximal to the wrist flexion crease or through an oblique
PLANTARIS When present, this tendon is consistently anterior to the Achilles tendon at its insertion in the calcaneus. A longitudinal incision is performed posterior to the medial malleolus (Fig 4A). The plantaris tendon is identified, divided, and tagged. Its loose adhesions to surrounding tissues are divided, and the tendon is retrieved with a long Brand stripper in a similar fashion as for the palmaris tendon (Fig 4B). It is important to point the stripper toward the lateral aspect of the knee joint, because the origin of the plantaris muscle is located in that area.
i ~-, ,: ,~.: , .,: .-. ,r-. i,~:.;;,,~-,:,~,,;.-,~.~- ~ c : : , ~ , r ~ i . : , : ~ ~ T , ~ i , , L v ' : ~
Fig 3. Harvest of a PL tendon with a Brand stripper. (A) The tagged tendon is threaded through the stripper. (B) The tendon is grasped with a small Kocher hemostat, and held taut, while the stripper is advanced with a rotary motion. (C) The tendon is retrieved with some muscle fibers attached.
294
MARWAN
A. W E H B E
A
Incision for
Second Toe Extensor
Fig 4. Incisions used to harvest tendon grafts from the lower extremity. (B) A long Brand stripper is used to harvest the plantaris and toe extensor tendons.
A
Fig 5. (A) Harvest of long toe extensor tendon. The second toe is the longest and most medial of this tendon mass. (B) Additional incisions may be necessary to free-up the second toe extensor proximally.
295
Fig 6. Portion of the abductor pollicis Iongus tendon can be harvested for use when doing a trapezium tendon Interposition arthroplasty (Anchovy). (A) The tendon dissection is started with a scalpel or mini-meniscotome. (B) A Brand stripper may be used to complete the harvest. (C) A significant length of tendon may be obtained without Interfering with thumb function.
LONG TOE EXTENSORS
LOCAL TENDONS
The long extensor of the second toe is the most easily harvested tendon of the toe extensors because of its position at the edge of the common long toe extensor tendon (Fig 5A). It can provide a substantial tendon graft. Its dissection is made difficult by the intervening extensor retinaculum, and the need to split it from the remaining tendon mass; however, this is facilitated by the use of a long tendon stripper (Fig 5B). A supplementary incision frequently has to be made proximal to the extensor retinaculum to complete the tendon harvesting (Fig 4A). The extensor digitorum brevis tendon is located lateral to the longus tendon at the insertion in the toe, and can be easily dissected out and preserved. The patient should be warned against the possibility of weak toe extension.
Up to 60% of the surface of a tendon can be harvested without weakening the tendon. 4 Usually, no separate incision is needed for this type of graft. The selected tendon insertion is identified and up to 50% of its substance is isolated for harvesting (Fig 6). This is typically obtained from the extensor carpi radialis or abductor pollicis longus tendons. The tendon is split longitudinally and proximally, the use of a "mini-meniscectomy" knife or a Bunnell or Brand stripper can facilitate that harvest (Fig 7). A separate proximal incision may be needed to divide the harvested portion of the tendon with minimal injury to the donor muscle.
GENERAL CONSIDERATIONS
Fig 7. Instruments used to harvest tendons for grafting: Brand stripper, Bunnell stripper, and Beaver mini-meniscotome. 296
Tendons in the upper limb can provide a graft length of 13 to 16 cm (rarely up to 19 cm), with a width of 3 mm. s'6 From the lower limb, a tendon graft measuring 35 cm in length can be commonly obtained; however, the usual width is 2 to 2.5 mm. 6 A wider graft can generally be obtained from the long second toe extensor. It is not clear what the optimal tendon width is for any particular application; however, tensile strength is related to crosssectional area. s A 2-mm tendon graft may not have the necessary strength to withstand the stresses applied on a profundus tendon. It should also be noted that the PL tendon may be absent in 25% of upper limbs, and in both limbs of 5% of people. If an upper extremity is found to be missing a MARWAN A. WEHBE
PL, there is a 28% chance of its being absent 6n the o t h e r side as well. T h e plantaris t e n d o n is absent in 19% of lower limbs, a n d in both lower limbs of 4% of people. If a lower extremity is f o u n d with no plantaris t e n d o n , the contralateral side will be deficient as well in 44% of people. 6 A Brand t e n d o n stripper 2 can greatly facilitate the harvest for all t e n d o n s discussed here. Varying degrees of preliminary dissection will be required, in particular for tendons that travel u n d e r n e a t h the extensor r e t i n a c u l u m of the wrist or ankle. A t e n d o n graft is u s e d to replace a portion of a t e n d o n that has b e e n d a m a g e d or resected, and occasionally as a substitute for a ligament. These conditions are usually self-limiting, so a d o n o r site s h o u l d be selected that
TENDON GRAFTING
would not cause a greater handicap than the problem being treated.
REFERENCES 1. Wehb6MA: Junctura tendinum. J Hand Surg [Am] 17:1124-1129,1992 2. Snow IW: Ulnar half of extensor digiti quinti proprius tendon for flexor grafts. Plast Reconstr Surg 42:603-604, 1968 3. Brand PW: Tendon grafting. J Bone Joint Surg [Br] 43:444-453, 1961 4. Cooney WP, Weidman KA, Malo DS, et al: Partial flexor tendon lacerations, in Hunter JM, Schneider LH, Mackin EJ (eds). Tendon Surgery in the Hand. St Louis, MO, Mosby, 1987, pp 148-155 5. Carlson GD, Botte MJ, Josephs MS, et al: Morphologic and biomechanical comparison of tendons used as free grafts. J Hand Surg [Am] 18:76-82, 1993 6. Wehb6 MA: Tendon graft donor sites. J Hand Surg [Am] 17:11301132, 1992
297