BACKGROUND
Calcaneal osteotomies have been performed for more than a century in an attempt to give long-standing correction to hindfoot deformities. First described by Gleich in 1893, the calcaneal osteotomy was popularized by Dwyer in 1963 to correct a varus deformity of the hindfoot, often associated with post-Polio (1). In 1971, Koutsogiannis reported on a medializing calcaneal osteotomy to assist in the correction of the pediatric, flexible flatfoot (2). Evans, in 1975, first described an anterior calcaneal osteotomy to lengthen the "lateral column" with a bone graft, and thereby correcting forefoot abduction in the pediatric flatfoot deformity (3). Evans suggested that tension on the plantar ligaments and peroneus longus tendon creates a bowstringing effect that restores the medial arch by adducting and plantarflexing the midfoot around the talo-navicular joint (3,4). Long term results were promising but complications including persistent calcaneocuboid pain and incomplete correction were noted (5,6).
In 1996 Myerson popularized the Koutsogiannis procedure for adults with acquired flatfoot with a medial displacement osteotomy (MDO) and FDL transfer (7). In an attempt to gain more frontal plane correction through a calcaneal osteotomy, both Malerba and Pisani reported on a Z- calcaneal osteotomy for the correction of hindfoot varus and valgus (8). This was an incomplete osteotomy, hinged on the medial side of the calcaneus. Weil , Jr. et al modified this configuration to a "scarf" design (interlocking segments) and described a triplane Calcaneal Scarf Osteotomy (CSO) for correction of flexible flatfoot deformity secondary to posterior tibial tendon dysfunction (PTTD) (9). The CSO combines the principles of both the medial displacement osteotomy (MDO) and Evans calcaneal osteotomy (ECO) in one contiguous osteotomy, addressing most components of a flatfoot deformity associated with PTTD.
The purpose of this study was to provide long-term subjective and radiographic results of the CSO for the surgical correction of PTTD.
MATERIALS AND METHODS
A total of 20 patients were retrospectively reviewed from October 2002 to July 2006. Patients were selected from the senior authors' clinic. Inclusion criteria included a painful Stage 2-3 flatfoot deformity (Johnson and Strom) unresponsive to conservative treatment outlined by ACFAS Current Procedural Guidelines.
The CSO was performed ,as depicted in Fig. 1,by the previously published technique (9). Postoperatively patients were placed in a below-the-knee cast for 4 weeks. Patients were encourage to begin "touchdown" weightbearing with crutches after 3 weeks.
Pre- and postoperative foot radiographs were obtained in the weightbearing position at 1 month, 1year and 2 years. Radiographic parameters measured on the anteroposterior (AP) view included talo-calcaneal angle , percentage of talar head coverage and calcaneocubiod angle (CCA). On the lateral view the calcaneal inclination angle (CIA), talo-calcaneal angle (TCA) and talo-first metatarsal angle (Meary's ) were measured. Postoperative radiographic data at 1 month, 1 year and last visit were compared to pre-operative data. Subjective data was obtained using the midfoot and rearfoot American Orthopedic Foot and Ankle Scoring system (AOFAS) postoperatively.
Descriptive statistics, including mean and standard deviation were used to describe demographic, radiographic and follow-up data. Pre- and postoperative radiographic variables were compared. A paired Student's t-test was performed to compare normally distributed continuous variables. Statistical differences were considered to be significant when the p-value was < 0.05.
IMAGES AND TABLES
Figure 1. Extensile incision and exposure of the lateral calcaneal wall (A). Completion of CSO (B). Ten millimeters of medial translation (C). Calcaneal elongation (insertion of bone graft) and correction of transverse plane (D). Single, cannulated screw for fixation (E).
| Follow-up |
Calcaneal Inclination Angle |
Meary's Angle |
Talo-Calcaneal Angle (AP) |
Talo-Navicular Coverage (%) |
AOFAS Midfoot Score |
AOFAS Ankle Score |
P-value |
| Pre-operative |
10.9° ± 4.47 |
22.60° ± 5.01 |
36.5° ± 10.06 |
36.75° ± 12.80
|
59.1 ± 9.98 |
55.8 ± 4.78 |
|
| 1 month postoperative |
19.87° ± 3.81 |
6.34° ± 7.25 |
18.1° ± 6.00 |
94.50° ± 7.50
|
|
|
< 0.001 |
| 1 year postoperative |
19.20° ± 3.07 |
7.54° ± 7.94 |
18.9° ± 6.29 |
93.25° ± 8.16
|
|
|
< 0.001 |
| 3 years postoperative |
17.79° ± 3.18
|
8.15° ± 8.89
|
18.72° ± 6.17
|
88.25° ± 19.89
|
96.2 ± 3.89 |
97.80 ± 2.00 |
< 0.001 |
RESULTS
Follow -up was performed in 20 patients with an average follow-up of 36 months. The average age was 46.95 ± 15.46. There were 9 (45%) females and 11 (55%) males. The operative side included 9 (45%) right and 11 (55%) left feet. Adjunctive procedures in combination with the CSO included: 15 percutaneous gastrocnemius lengthenings(75%); 9 Cotton osteotomies (40%); 8 Cobb transfers (40%); 5 FDL transfers (25%); 5 Kidners (25%); 5 arthroereisis (25%); 3 (15%) spring ligament repairs; 1 navicular-cuneiform fusion (5%); 1 Lapidius fusion (5%). Table 1 contains radiographic results pre-operatively and postoperatively at 1 month, 1 year and 3 years.
Complications included 5 (25%) screw removals, 2 (10%) delayed unions, 1 (5%) lateral column pain and 1 (5%) resolved DVT.
Figure 2. Pediatric case with plantar screw and arthroereisis.
DISCUSSION AND CONCLUSIONS
The advantages of the CSO are:
- Ability to correct a tri-plane deformity through a single, contiguous osteotomy.
- Inherently stable osteotomy with interlocking joints that allows patients to initiate partial weight-bearing with crutches at 3 weeks post operatively.
- Minimal post-operative complaints of calcaneo-cuboid pain.
- Ability to use bone allografts or substitutes as bone void fillers and not rely on the graft to maintain structural alignment.
- Fixation using a single 6.5 screw without extra plating for the lateral column.
- Can be implemented in pediatric patients without disruption of the open growth plate using a percutaneous screw that does not traverse the open growth plate (fig. 2).
1. Gleich A. Beitrag zur operativen plattfussbehandlung. Arch Klinn Chir. 1893;46:358-362.
2. Koutsogiannis E. Treatment of mobile flat foot by displacement osteotomy of the calcaneus. J Bone Joint Surg 1971;53(B):96-100.
3. Evans D. Calcaneo-valgus deformity. J Bone Joint Surg 1975;57(B)270-278.
4. Sangeorzan BJ, Mosca V, Hansen ST. Effect of calcaneal lengthening on relationships among the hindfoot, midfoot, and forefoot. Foot Ankle. 1993;14:136-141.
5. Anderson RB, Davis WH. Calcaneocuboid distraction arthrodesis for the treatment of the adult acquired flatfoot. Foot Ankle Clin 1996; 1:279.
6. Weil, Jr LS, Benton-Weil W, et al. Outcomes for surgical correction for stages 2 and 3 tibialis posterior dysfunction. J Foot Ankle Surg 1998;37(6):467-471.
7. Myerson MS, Corrigan J. Treatment of posterior tibial tendon dysfunction with flexor digitorum longus tendon transfer and calcaneal osteotomy. Orthopedics 1996;19:383-388
8. Malerba F, Marchi F. Calcaneal Osteotomies. Foot Ankle Clin N Am 2005;10:523-40.
9. Weil, Jr. LS, Roukis TS. The Calcaneal Scarf Osteotomy: Operative Technique. J Foot Ankle Surg 2001;40(3):178-82.
10. Moseir-Laclair S, Pomeroy G, Manoli A: Intermediate follow-up on the double osteotomy and tendon transfer procedure for stage II posterior tibial tendon insufficiency. Foot Ankle Int 22: 283, 2001.
Weil Foot & Ankle Institute
(847) 390-7666
Email : info@weil4feet.com
Website : www.weil4feet.com
