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The calcaneal scarf osteotomy: Operative technique
TIPS, QUIPS, AND PEARLS
"Tips, Quips, and Pearls" is a special section in The Journal of Foot & Ankle Surgery which is devoted to the sharing of ideas to make the practice of foot and ankle surgery easier. We invite our readers to share ideas with us in the f orm of special tips regarding diagnostic or surgical procedures, new devices or modifications of devices for making a surgical procedure a little bit easier, or virtually any other "pearl" that the reader believes will assist the foot and ankle surgeon in providing better care. Please address your tips to: Lowell Scott Weil, Sr., DPM, Editor-in-Chief, The Journal of Foot & Ankle Surgery , 1455 Golf Road, Des Plaines, 1L 60016; Fax: 847-729-0099; E-mail: LSWSR @aol.com
The Calcaneal Scarf Osteotomy: Operative Technique Lowell Scott Weil, Jr., DPM, FACFAS,1 and Thomas S. Roukis, DPM, AACFAS 2 The first calcaneal osteotomy applied to the flatfoot deformity was described by Gleich in 1893 (1) . A modification of Gleich ' s osteotom y, the straight medial slide calcaneal osteotomy, was described by Koutsogiannis in 1971 (2) and has recently been studied in-depth and popul arized by Myer son and colleagues (3, 4). Deland et al. (5) described the placement of a laterally based truncated bone graft wedge interpo sed within the medial slide calcaneal osteotom y in order to structurally lengthen the calcaneus, similar in concept to the opening wedge calcaneal osteotom y of Silver (6). In a cadaveric study, Deland et al. (5) found statistically significant correction of the surgically induced flatfoot deformit y comparable to that produced through the double calcaneal osteotomy described by Pomeroy and Manoli (7) which cons isted of combined medial slide calcaneal osteotomy and anterior calcaneal lengthening osteotomies. There have been several reports of midfoot osteotomies with bone graft insertion to lengthen the lateral column. Medial column shortening and lateral column lengthenin g, through removal of a medially based bone wedge from the navicular and interpo sition of the bone graft wedge within the anterior calcaneus was initially described by Perth (8). Evans performed an opening wedge osteotomy with insertion of a bone graft wedge at the level of the anterior process of the calcaneus and popularized the From Weil Foot & Ankle Institute. Des Plaines. IL. Address corre spondence to: Thomas S. Roukis, DPM . 1455 E. Golf Road, # 131, Des Plaines. IL 600 16; e-mail: [weiljr @weiI4feet.com . I Director. Foot and Ankle Fellowship. 2 Foot and Ankle Fellow. The Journal of Foot & Ankle Surgery 1067-2516/01/4003-0178$4.00/0 Copyright © 2001 by the American College of Foot and Ankle Surgeons
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technique (9). Recently, the calcaneocuboid joint distraction arthrodesis has been studied in-depth by Hansen and Sangeorzan (l0, II ) as an alternative to lateral column lengthening since the public ation of a biomechanical report that suggested lengthening via calcaneal osteotomy generates excessiv e pressures within the calcaneocuboid joint (12). Furthermore, Weil, Jr. et al. (13) found that 50% of the patients undergoin g a Cobb-Evans procedure felt that the procedure did not meet their expectation s, while one out of the five Cobb procedure patient s felt that the procedure did not meet their expectati ons. They concluded that although lateral column lengthening with tendon augmentation renders good radiographic correction, many patients develop protracted lateral column pain and felt that surgery did not meet their expectations. Weil, Jr., et al. concluded that additional calcaneal osteot omie s and arthrodesing procedures of the hindfoot may render a more satisfactory outcome. Malerba and De Marchi (14) and Pisani (15) have each described a lateral closing wedge calcaneal Z-osteotom y for correction of hindfoot varus deformit y. The senior author (L.S.W., Jr.) subsequently modified the configuration of the osteotomy to a scarf design and applied the concepts of the medial slide osteotomy, structural varisation, and calcane al lengthening allowing for triplane correction of the adult collapsing pes planovalgus deformity secondary to posterior tibiali s tendon dysfunction. Surgical Technique
The extensile lateral incision of Dwyer ( 16) is utilized to develop exposure of the lateral wall of the calcaneus (Fig. I). The sural nerve, lateral malleolar, and lateral
Lateral view of hindfoot with placement and extent of extensile skin incision outlined (hashed line). FM, fibular malleolus; SP, styloid process fifth metatarsal; AT, Achilles tendon. FIGURE 1
FIGURE 2 Full-thickness subperiosteal flap dissection is demonstrated. PT, peroneal tubercle; ADM, abductor digiti minimi.
calcaneal arteries, as well as the peroneal tendons are all well protected and avoided with this approach (17). A full-thickness fasciocutaneous flap is then raised to expose the lateral aspect of the calcaneus (Fig. 2) and a scarf osteotomy is outlined and consists of a longitudinal central arm, a dorsal-proximal arm, and a plantar-distal arm. The dorsal-proximal arm is located one-third the distance between the posterior-superior aspect of the calcaneal tuber posteriorly and the posterior aspect of the subtalar joint anteriorly. The distal-plantar arm is located directly inline with the lateral talar process, approximately 2 em anterior to the plantar lateral calcaneal tuber. Both the dorsal-proximal and plantar-distal arms are 10-15 mm in length. The longitudinal central arm is oriented with a 30° plantar declination just inferior to the calcaneal-fibular
FIGURE 3
Configuration of calcaneal scarf osteotomy is outlined. Note the vertically oriented dorsal-proximal and plantar-distal arms of the osteotomy and 30° plantar inclination of central arm.
FIGURE 4 A guide-wire and an osteotomy guide are utilized to assure coaxial placement of each osteotomy arm.
ligament insertion, while both the dorsal-proximal and plantar-distal arms are vertically oriented (Fig. 3). An osteotomy guide is utilized to assure precise coaxial placement of each arm of the osteotomy (Fig. 4). If the osteotomy is oriented directly from medial to lateral, straight medial transposition of the calcaneal tuber will occur. However, if the osteotomy was oriented from dorsal-lateral to plantar-medial then the calcaneal tuber will be transposed in a plantar-medial direction. Once the proper orientation is determined, the osteotomy is created with a large sagittal saw in through-and-through fashion for each arm of the osteotomy with care taken to very carefully score the medial internal cortex of the calcaneus. The saw is directly visualized exiting the dorsal-proximal and VOLUME 40, NUMBER 3, MAY/JUNE 2001
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FIGURE 5 The completed osteotomy after medial displacement of the calcaneal tuber.
FIGURE 7 Axial view of medial displacement combined with placement of a laterally based, truncated bone graft for structural varisation of the calcaneal tuber.
FIGURE 6 Medial displacement combined with placement of a laterally based, truncated bone graft for structural varisation of the calcaneal tuber.
plantar-distal arms of the osteotomy . A wide osteotom e is then placed within the longitudinal, central arm and gently rotated in order to complete the osteotomy. A smooth laminar spreader is then inserted deep within the longitudinal central arm and gently dialed open in order to distract the soft-tissue structures on the medial aspect of the calcaneus, which can tether the calcaneal tuber and limit the amount of medial displacement possible. Once the osteotomy is completed, the posterior calcaneal tuber can then be mediali zed 10-15 mm (Fig. 5). In addition to medial displacement of the posterior calca neal tuber, structural varisation of the calcaneus can be achieved by placement of laterally based truncated bone graft within the central arm of the osteotomy in order to rotate the tuber within the frontal plane (Fig. 6 and 7). 180
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FIGURE 8 Medial displacement combined with placement of bone graft wedges (solid arrows) within proximal-dorsal and distal-plantar osteotomy arms for structural lengthening of the calcaneus.
More importantl y, calcaneal lengthening and concomitant transverse plane correction of forefoot abduction are achieved through the placement of bone wedges with in the proximal-dorsal and distal-plantar arms of the osteotomy (Fig. 8). A small laminar spreader is placed within the
FIGURE 9 Preoperative (A) and postoperative (B) lateral radiographs demonstrating the proximal-dorsal and distal-plantar allograft bone wedges (solid arrows) and placement of a large compression screw.
distal-plantar arm of the osteotomy and gently dialed open until the forefoot abduction is reduced to the desired degree, at which point a calculation of the depth and width of the bone graft necessary to maintain the correction is determined. An iliac crest allograft is then tailored to the appropriate size and gently impacted within the proximaldorsal arm of the osteotomy. The laminar spreader is removed and a second bone graft of similar dimensions to the first is then gently impacted within the distal-plantar arm of the osteotomy. Once the desired reduction is obtained, a O.062-inch Kirschner wire is utilized to temporarily maintain the position of the osteotomy. The osteotomy is fixated by a single, cannulated compression screw (Fig. 9). The prominent, over-hanging remnant lateral wall of the calcaneus is gently compacted flush with the remaining calcaneal tuber. When a percutaneous Achilles tendon lengthening is performed in conjunction with the scarf calcaneal
osteotomy, the lengthening is routinely completed prior to the osteotomy (18). Any concomitant soft-tissue procedures, such as Cobb anterior tibial tenodesis or flexor digitorum longus tendon transfer, are then completed (3, 4, 18). A well-padded surgical dressing and short-leg nonweightbearing fiberglass cast are applied for 6 weeks. Guarded weightbearing and a formal rehabilitation program are then instituted. Conclusion
Through a single osteotomy, the calcaneal scarf osteotomy allows for triplane correction of the hindfoot and midfoot deformities present in the adult acquired flatfoot. The configuration of the osteotomy allows for stable and rapid consolidation of the osteotomy and allograft bone wedges (Fig. 9). VOLUME 40, NUMBER 3, MAY/JUNE 2001
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References I. Gleich, A. Beitrag zur operativen plattfussbehandlung. Arch. Klin. Chir. 46:358-362,1893. 2. Koutsogiannis, E. Treatment of mobile flat foot by displacement osteotomy of the calcaneus. J. Bone Joint Surg. 53-B:96-100, 1971. 3. Myerson, M. S., Corrigan, J., Thompson, F., Schon, L. C. Tendon transfer combined with calcaneal osteotomy for the treatment of posterior tibial tendon insufficiency: a radiological investigation. Foot Ankle Int. 16:712-718, 1995. 4. Myerson, M. S., Corrigan, 1. Treatment of posterior tibial tendon dysfunction with flexor digitorum longus tendon transfer and calcaneal osteotomy. Orthopedics 19:383-388, 1996. 5. Deland, 1. T., Page, A. E., Kenneally, S. M. Posterior calcaneal osteotomy with wedge: cadaver testing of a new procedure for insufficiency of the posterior tibial tendon. Foot Ankle Int. 20(5):290-295, 1999. 6. Silver, C. M., Simon, S. D., Licthman, H. M. Long-term follow-up observations on calcaneal osteotomy. Clin. Orthop. 99:181-187, 1974. 7. Pomeroy, G. C., Manoli, A. A new operative approach for flatfoot secondary to posterior tibial tendon insufficiency: a preliminary report. Foot Ankle Int. 18(4):206-212, 1997. 8. Perth. Deutsch. Ztschr. F. Chir, April 12, 1913, cited in Whitman, R. Disabilities and deformities of the foot: weak foot, ch. 20. A Treatise on Orthopaedic Surgery, p. 697, Lea & Febiger, Philadelphia, 1919.
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9. Evans, D. Calcaneo-valgus deformity. J. Bone Joint Surg. 57B:270-278, 1975. 10. Toolan, B. c., Sangeorzan, B. 1., Hansen, S. T. Complex reconstruction for the treatment of dorsolateral peritalar subluxation of the foot. J. Bone Joint Surg. 81-A(lI):1545-1560, 1999. II. Chi, T. D., Toolan, B. Sangeorzan, B. 1., Hansen, S. T. The lateral column lengthening and medial column stabilization procedures. Clin. Orthop. 365:81-90, 1999. 12. Cooper, P. S., Nowak, M. D., Shaer, J. Calcaneocuboid joint pressures with lateral column lengthening (Evans) procedure. Foot Ankle Int. 18(4):199-205, 1997. 13. Weil, L. S., Jr., Benton-Weil, W., Borrelli, A. H., Wei!, L. S., Sr. Outcomes for surgical correction for stages 2 and 3 tibialis posterior dysfunction. J. Foot Ankle Surg. 37(6):467 -471, 1998. 14. Malerba, F., De Marchi, F. French Society of Foot and Ankle Surgery, Paris, September 1997. Personal communication with Lowell Scott Weil, Jr., DPM. 15. Pisani, G. French Society of Foot and Ankle Surgery, Paris, September 1997. Personal communication with Lowell Scott Weil, Jr., DPM. 16. Dwyer, F. Personal communication with Lowell Scott Weil, Sr., DPM, Grand Rounds Lecture Series: Children's Memorial Hospital, Chicago, IL, November 1975. 17. Borrelli, Jr., J., Lashgari, C. Vascularity of the lateral calcaneal flap: a cadaveric injection study. 1. Orthop. Trauma 13(2):73-77, 1999. 18. Benton-Weil, W., Weil, L. S., Jr. The Cobb procedure for stage II posterior tibial tendon dysfunction. Clin. Podiatr. Med. Surg. 16(3):471-477, 1999.
c.
"Tips, Quips, and Pearls" is a special section in The Journal of Foot & Ankle Surgery which is devoted to the sharing of ideas to make the practice of foot and ankle surgery easier. We invite our readers to share ideas with us in the f orm of special tips regarding diagnostic or surgical procedures, new devices or modifications of devices for making a surgical procedure a little bit easier, or virtually any other "pearl" that the reader believes will assist the foot and ankle surgeon in providing better care. Please address your tips to: Lowell Scott Weil, Sr., DPM, Editor-in-Chief, The Journal of Foot & Ankle Surgery , 1455 Golf Road, Des Plaines, 1L 60016; Fax: 847-729-0099; E-mail: LSWSR @aol.com
The Calcaneal Scarf Osteotomy: Operative Technique Lowell Scott Weil, Jr., DPM, FACFAS,1 and Thomas S. Roukis, DPM, AACFAS 2 The first calcaneal osteotomy applied to the flatfoot deformity was described by Gleich in 1893 (1) . A modification of Gleich ' s osteotom y, the straight medial slide calcaneal osteotomy, was described by Koutsogiannis in 1971 (2) and has recently been studied in-depth and popul arized by Myer son and colleagues (3, 4). Deland et al. (5) described the placement of a laterally based truncated bone graft wedge interpo sed within the medial slide calcaneal osteotom y in order to structurally lengthen the calcaneus, similar in concept to the opening wedge calcaneal osteotom y of Silver (6). In a cadaveric study, Deland et al. (5) found statistically significant correction of the surgically induced flatfoot deformit y comparable to that produced through the double calcaneal osteotomy described by Pomeroy and Manoli (7) which cons isted of combined medial slide calcaneal osteotomy and anterior calcaneal lengthening osteotomies. There have been several reports of midfoot osteotomies with bone graft insertion to lengthen the lateral column. Medial column shortening and lateral column lengthenin g, through removal of a medially based bone wedge from the navicular and interpo sition of the bone graft wedge within the anterior calcaneus was initially described by Perth (8). Evans performed an opening wedge osteotomy with insertion of a bone graft wedge at the level of the anterior process of the calcaneus and popularized the From Weil Foot & Ankle Institute. Des Plaines. IL. Address corre spondence to: Thomas S. Roukis, DPM . 1455 E. Golf Road, # 131, Des Plaines. IL 600 16; e-mail: [weiljr @weiI4feet.com . I Director. Foot and Ankle Fellowship. 2 Foot and Ankle Fellow. The Journal of Foot & Ankle Surgery 1067-2516/01/4003-0178$4.00/0 Copyright © 2001 by the American College of Foot and Ankle Surgeons
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technique (9). Recently, the calcaneocuboid joint distraction arthrodesis has been studied in-depth by Hansen and Sangeorzan (l0, II ) as an alternative to lateral column lengthening since the public ation of a biomechanical report that suggested lengthening via calcaneal osteotomy generates excessiv e pressures within the calcaneocuboid joint (12). Furthermore, Weil, Jr. et al. (13) found that 50% of the patients undergoin g a Cobb-Evans procedure felt that the procedure did not meet their expectation s, while one out of the five Cobb procedure patient s felt that the procedure did not meet their expectati ons. They concluded that although lateral column lengthening with tendon augmentation renders good radiographic correction, many patients develop protracted lateral column pain and felt that surgery did not meet their expectations. Weil, Jr., et al. concluded that additional calcaneal osteot omie s and arthrodesing procedures of the hindfoot may render a more satisfactory outcome. Malerba and De Marchi (14) and Pisani (15) have each described a lateral closing wedge calcaneal Z-osteotom y for correction of hindfoot varus deformit y. The senior author (L.S.W., Jr.) subsequently modified the configuration of the osteotomy to a scarf design and applied the concepts of the medial slide osteotomy, structural varisation, and calcane al lengthening allowing for triplane correction of the adult collapsing pes planovalgus deformity secondary to posterior tibiali s tendon dysfunction. Surgical Technique
The extensile lateral incision of Dwyer ( 16) is utilized to develop exposure of the lateral wall of the calcaneus (Fig. I). The sural nerve, lateral malleolar, and lateral
Lateral view of hindfoot with placement and extent of extensile skin incision outlined (hashed line). FM, fibular malleolus; SP, styloid process fifth metatarsal; AT, Achilles tendon. FIGURE 1
FIGURE 2 Full-thickness subperiosteal flap dissection is demonstrated. PT, peroneal tubercle; ADM, abductor digiti minimi.
calcaneal arteries, as well as the peroneal tendons are all well protected and avoided with this approach (17). A full-thickness fasciocutaneous flap is then raised to expose the lateral aspect of the calcaneus (Fig. 2) and a scarf osteotomy is outlined and consists of a longitudinal central arm, a dorsal-proximal arm, and a plantar-distal arm. The dorsal-proximal arm is located one-third the distance between the posterior-superior aspect of the calcaneal tuber posteriorly and the posterior aspect of the subtalar joint anteriorly. The distal-plantar arm is located directly inline with the lateral talar process, approximately 2 em anterior to the plantar lateral calcaneal tuber. Both the dorsal-proximal and plantar-distal arms are 10-15 mm in length. The longitudinal central arm is oriented with a 30° plantar declination just inferior to the calcaneal-fibular
FIGURE 3
Configuration of calcaneal scarf osteotomy is outlined. Note the vertically oriented dorsal-proximal and plantar-distal arms of the osteotomy and 30° plantar inclination of central arm.
FIGURE 4 A guide-wire and an osteotomy guide are utilized to assure coaxial placement of each osteotomy arm.
ligament insertion, while both the dorsal-proximal and plantar-distal arms are vertically oriented (Fig. 3). An osteotomy guide is utilized to assure precise coaxial placement of each arm of the osteotomy (Fig. 4). If the osteotomy is oriented directly from medial to lateral, straight medial transposition of the calcaneal tuber will occur. However, if the osteotomy was oriented from dorsal-lateral to plantar-medial then the calcaneal tuber will be transposed in a plantar-medial direction. Once the proper orientation is determined, the osteotomy is created with a large sagittal saw in through-and-through fashion for each arm of the osteotomy with care taken to very carefully score the medial internal cortex of the calcaneus. The saw is directly visualized exiting the dorsal-proximal and VOLUME 40, NUMBER 3, MAY/JUNE 2001
179
FIGURE 5 The completed osteotomy after medial displacement of the calcaneal tuber.
FIGURE 7 Axial view of medial displacement combined with placement of a laterally based, truncated bone graft for structural varisation of the calcaneal tuber.
FIGURE 6 Medial displacement combined with placement of a laterally based, truncated bone graft for structural varisation of the calcaneal tuber.
plantar-distal arms of the osteotomy . A wide osteotom e is then placed within the longitudinal, central arm and gently rotated in order to complete the osteotomy. A smooth laminar spreader is then inserted deep within the longitudinal central arm and gently dialed open in order to distract the soft-tissue structures on the medial aspect of the calcaneus, which can tether the calcaneal tuber and limit the amount of medial displacement possible. Once the osteotomy is completed, the posterior calcaneal tuber can then be mediali zed 10-15 mm (Fig. 5). In addition to medial displacement of the posterior calca neal tuber, structural varisation of the calcaneus can be achieved by placement of laterally based truncated bone graft within the central arm of the osteotomy in order to rotate the tuber within the frontal plane (Fig. 6 and 7). 180
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FIGURE 8 Medial displacement combined with placement of bone graft wedges (solid arrows) within proximal-dorsal and distal-plantar osteotomy arms for structural lengthening of the calcaneus.
More importantl y, calcaneal lengthening and concomitant transverse plane correction of forefoot abduction are achieved through the placement of bone wedges with in the proximal-dorsal and distal-plantar arms of the osteotomy (Fig. 8). A small laminar spreader is placed within the
FIGURE 9 Preoperative (A) and postoperative (B) lateral radiographs demonstrating the proximal-dorsal and distal-plantar allograft bone wedges (solid arrows) and placement of a large compression screw.
distal-plantar arm of the osteotomy and gently dialed open until the forefoot abduction is reduced to the desired degree, at which point a calculation of the depth and width of the bone graft necessary to maintain the correction is determined. An iliac crest allograft is then tailored to the appropriate size and gently impacted within the proximaldorsal arm of the osteotomy. The laminar spreader is removed and a second bone graft of similar dimensions to the first is then gently impacted within the distal-plantar arm of the osteotomy. Once the desired reduction is obtained, a O.062-inch Kirschner wire is utilized to temporarily maintain the position of the osteotomy. The osteotomy is fixated by a single, cannulated compression screw (Fig. 9). The prominent, over-hanging remnant lateral wall of the calcaneus is gently compacted flush with the remaining calcaneal tuber. When a percutaneous Achilles tendon lengthening is performed in conjunction with the scarf calcaneal
osteotomy, the lengthening is routinely completed prior to the osteotomy (18). Any concomitant soft-tissue procedures, such as Cobb anterior tibial tenodesis or flexor digitorum longus tendon transfer, are then completed (3, 4, 18). A well-padded surgical dressing and short-leg nonweightbearing fiberglass cast are applied for 6 weeks. Guarded weightbearing and a formal rehabilitation program are then instituted. Conclusion
Through a single osteotomy, the calcaneal scarf osteotomy allows for triplane correction of the hindfoot and midfoot deformities present in the adult acquired flatfoot. The configuration of the osteotomy allows for stable and rapid consolidation of the osteotomy and allograft bone wedges (Fig. 9). VOLUME 40, NUMBER 3, MAY/JUNE 2001
181
References I. Gleich, A. Beitrag zur operativen plattfussbehandlung. Arch. Klin. Chir. 46:358-362,1893. 2. Koutsogiannis, E. Treatment of mobile flat foot by displacement osteotomy of the calcaneus. J. Bone Joint Surg. 53-B:96-100, 1971. 3. Myerson, M. S., Corrigan, J., Thompson, F., Schon, L. C. Tendon transfer combined with calcaneal osteotomy for the treatment of posterior tibial tendon insufficiency: a radiological investigation. Foot Ankle Int. 16:712-718, 1995. 4. Myerson, M. S., Corrigan, 1. Treatment of posterior tibial tendon dysfunction with flexor digitorum longus tendon transfer and calcaneal osteotomy. Orthopedics 19:383-388, 1996. 5. Deland, 1. T., Page, A. E., Kenneally, S. M. Posterior calcaneal osteotomy with wedge: cadaver testing of a new procedure for insufficiency of the posterior tibial tendon. Foot Ankle Int. 20(5):290-295, 1999. 6. Silver, C. M., Simon, S. D., Licthman, H. M. Long-term follow-up observations on calcaneal osteotomy. Clin. Orthop. 99:181-187, 1974. 7. Pomeroy, G. C., Manoli, A. A new operative approach for flatfoot secondary to posterior tibial tendon insufficiency: a preliminary report. Foot Ankle Int. 18(4):206-212, 1997. 8. Perth. Deutsch. Ztschr. F. Chir, April 12, 1913, cited in Whitman, R. Disabilities and deformities of the foot: weak foot, ch. 20. A Treatise on Orthopaedic Surgery, p. 697, Lea & Febiger, Philadelphia, 1919.
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9. Evans, D. Calcaneo-valgus deformity. J. Bone Joint Surg. 57B:270-278, 1975. 10. Toolan, B. c., Sangeorzan, B. 1., Hansen, S. T. Complex reconstruction for the treatment of dorsolateral peritalar subluxation of the foot. J. Bone Joint Surg. 81-A(lI):1545-1560, 1999. II. Chi, T. D., Toolan, B. Sangeorzan, B. 1., Hansen, S. T. The lateral column lengthening and medial column stabilization procedures. Clin. Orthop. 365:81-90, 1999. 12. Cooper, P. S., Nowak, M. D., Shaer, J. Calcaneocuboid joint pressures with lateral column lengthening (Evans) procedure. Foot Ankle Int. 18(4):199-205, 1997. 13. Weil, L. S., Jr., Benton-Weil, W., Borrelli, A. H., Wei!, L. S., Sr. Outcomes for surgical correction for stages 2 and 3 tibialis posterior dysfunction. J. Foot Ankle Surg. 37(6):467 -471, 1998. 14. Malerba, F., De Marchi, F. French Society of Foot and Ankle Surgery, Paris, September 1997. Personal communication with Lowell Scott Weil, Jr., DPM. 15. Pisani, G. French Society of Foot and Ankle Surgery, Paris, September 1997. Personal communication with Lowell Scott Weil, Jr., DPM. 16. Dwyer, F. Personal communication with Lowell Scott Weil, Sr., DPM, Grand Rounds Lecture Series: Children's Memorial Hospital, Chicago, IL, November 1975. 17. Borrelli, Jr., J., Lashgari, C. Vascularity of the lateral calcaneal flap: a cadaveric injection study. 1. Orthop. Trauma 13(2):73-77, 1999. 18. Benton-Weil, W., Weil, L. S., Jr. The Cobb procedure for stage II posterior tibial tendon dysfunction. Clin. Podiatr. Med. Surg. 16(3):471-477, 1999.
c.