Address for Correspondence
Chikahisa Higuchi, M.D., Ph.D.
Department of Orthopaedics,
Osaka University Graduate School of Medicine,
2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
Tel. +81-6-6879-3552
Fax. +81-6-6879-3559
E-mail : c-higuchi@umin.ac.jp
Abstract
Purpose
Achilles tenotomy is the final step for the correction of idiopathic clubfoot in the Ponseti technique. We ultrasonographically evaluated the continuity of Achilles tendon before and after tenotomy.
Methods
Between April 2006 and July 2008, 8 children (6 boys, 2 girls) with 10 club feet were enrolled in this study. All club feet had already been treated by serial casting and were at the point of requiring Achilles tenotomy. Tenotomy was performed percutaneously in accordance with the Ponseti method. Range of motion at the ankle was recorded before and after the operation under general anesthesia. Ultrasonographic evaluations were made before and immediately after tenotomy and at 3 weeks postoperatively.
Results
In this study of 10 tendons in 8 infants, mean elongated length of the tendon was 10.8 mm and continuity was confirmed by ultrasonographic evaluation 3 weeks after tenotomy. Mean range of ankle dorsiflexion after the procedure was 44.5° and a positive correlation with elongated length of the tendon was seen.
Conclusions
Ultrasonographic findings show a positive correlation between elongation of the tendon and improvement of ankle dorsiflexion. These findings suggest that ultrasonographic evaluation is useful for observing regeneration of the Achilles tendon in the Ponseti technique.
J.Orthopaedics 2011;8(2)e1
Key Words
ultrasonography; idiopathic clubfoot; Achilles tenotomy
Introduction
Congenital idiopathic clubfoot is a complex anomaly including forefoot adduction, hindfoot varus, and equinus deformities. The Ponseti method is widely used around the world for the treatment of clubfoot [1-5]. This maneuver consists of serial manipulations and casting for the deformities other than equines deformities. For talipes equinus, percutaneous Achilles tenotomy was recommended in the original method. Ponseti and others have reported clinical continuity of the divided tendon after tenotomy and good results for the correction of deformities [6-8]. Baker et al. showed continuity of the tendon 6 weeks after tenotomy using ultrasonography [9]. Maranho et al. reported healing process of the tendon after temotomy using ultrasonography [10].
We also perform the Ponseti technique for treatment of clubfoot and have achieved good results with this treatment. In the process of treatment, we use ultrasonographic evaluation to confirm complete tenotomy of the Achilles tendon and monitor the process of tendon healing.
The aim of this study was to ultrasonographically evaluate elongated length of the dissected tendon and the duration of healing.
Patients and Methods
Between April 2006 and July 2008, 8 children (6 boys, 2 girls) with 10 club feet were enrolled in this study. Two boys showed bilateral deformity. One boy displayed other anomaly of the upper limbs. All club feet had already been treated by serial casting and were at the point of requiring Achilles tenotomy. Tenotomy was performed percutaneously using a rounded blade 0.5 cm above the calcaneus, in accordance with the Ponseti method. Range of motion at the ankle was recorded before and after the operation under general anesthesia. Mean age at tenotomy was 76.4 days (range, 39-166 days).
Ultrasonographic evaluations were made before and immediately after tenotomy using a scanner with a 7.5-MHz probe (Toshiba, Japan). An ultrasound scan was taken over the posterior aspect of the lower leg, creating an image of the Achilles tendon, calcaneus, and posterior aspect of the tibia. Distance between the distal edge of the proximal tendon and the calcaneus (corrected distance) was recorded by postoperative scanning. Corrected distance was measured when the affected limb was in 90° of knee flexion and 0° of ankle dorsal flexion.
After complete tenotomy was verified by clinical and ultrasonographic findings, the affected limb was kept in a long leg cast with the knee in 90° of flexion and the ankle in 0° of dorsiflexion for 4 weeks. After cast removal, a foot-abduction brace was applied for as long as possible. Final ultrasonographic assessment was undertaken at 3 weeks after tenotomy to check on continuity of the tendon.
Results
Tenotomy was performed without injury of the neurovascular bundle or skin disturbance. Complete release of the tendon was clinically assessed by absence of the heel cord and appearance of the hollow above the calcaneus. Mean level of dorsiflexion was -25.5° (range, -45° to -5°) before and 22.0° (range, 10° to 35°) after tenotomy.
Achilles tendons in all feet were demonstrated by preoperative ultrasonography (Fig. 1). Ultrasonographic imaging demonstrated the Achilles tendon (Fig. 1, between arrows), calcaneus, and posterior aspect of the tibia. The image showed the insertion of the tendon into the calcaneus (Fig. 1, arrowheads).
Figure 1
Ultrasonographic image of posterior aspect of lower leg before Achilles tenotomy
Postoperative ultrasonographic imaging demonstrated a gap in the tendon suggesting discontinuity (Fig. 2). Complete tenotomy was ultrasonographically confirmed by this image. The corrected distance could be measured after detection of the proximal cut edge (Fig. 2, between arrowheads).
Figure 2
Ultrasonographic image of posterior aspect of lower leg after tenotomy
Regeneration of the Achilles tendon was confirmed by ultrasonographic findings 3 weeks postoperatively. Tendon continuity was demonstrated in all feet (Fig. 3, arrowhead).
Figure 3
Ultrasonographic image of Achilles tendon 3 weeks postoperatively
Mean corrected distance was 10.8 mm (range, 5.5-18.3 mm). Figure 4 shows a positive correlation between corrected distance and improved range of dorsiflexion (correlation coefficient, 0.747).
Figure 4
Correlation between elongation of Achilles tendon and improvement of dorsiflexion in ankle
Discussion
Percutaneous tenotomy of Achilles tendon is an important in for the treatment of clubfoot deformity using the Ponseti method. Lengthening of tendons is usually performed and complete tenotomy is not always applied for the correction of skeletal deformities. This situation makes lack of healing a concern for orthopedic surgeons. In addition, condition of the Achilles tendon after tenotomy is not well understood except from the perspective of clinical assessments. The present findings suggest that tenotomy of the Achilles tendon in the Ponseti method does not result in loss of tendon healing and that clinical assessment of improvement in ankle dorsiflexion correlates significantly with evidence from ultrasonographic imaging. Baker et al. reported the usefulness of ultrasonographic assessment after tenotomy. Their report demonstrated continuity and healing of the tendon on ultrasonography [9]. They suggested that the Achilles tendon can heal within 6 weeks. On the other hand, Maranho et al. showed healing process of the tendon using ultrasonography [10]. They suggested that the continuity of the tendon was confirmed at 3 weeks postoperatively and that the tendon healing was complete at 6 months postprocedure. We assessed the Achilles tendon before and after tenotomy according to their ultrasonographic method. Our results have also shown continuity of the tendon is reconstructed within 3 weeks after tenotomy. No treated tendons in this study ruptured after cast removal and no relapse of deformities was recognized. Four-week casting after tenotomy is thus sufficient for tendon healing.
We assessed the sectioned tendon using ultrasonography. Baker et al. demonstrated a gap in the Achilles tendon after tenotomy in their report. However, they did not assess the cut tendon and no reports have described assessment of the cut tendon in the Ponseti method. As expected, elongation of the Achilles tendon correlated positively with improved range of dorsiflexion (Fig. 4). Greater improvement of ankle dorsiflexion was thus associated with larger corrected distance. Maximum corrected distance was 18.3 mm and the defect in continuity was large. In that case, we were able to confirm healing of the Achilles tendon by ultrasonographic imaging with no rupture after healing. These results suggest that manipulation of dorsiflexion after tenotomy should be performed as much as possible without fear of non-healing or rupture of the tendon. In addition, we have since encountered a case (not included in this study) with no complications and no relapse after second tenotomy at 21 months old. Ultrasonography and magnetic resonance imaging in that case revealed complete healing of the tendon. The present results and our experience have shown evidence of Achilles tendon regeneration after tenotomy.
In summary, this study demonstrated ultrasonographic evidence of Achilles tendon healing after tenotomy. Ultrasonographic findings show a positive correlation between elongation of the tendon and improvement of ankle dorsiflexion. Ultrasonographic evaluation is a useful method for confirming clinical findings.
References
1. Ponseti IV. Treatment of congenital club foot. J Bone Joint Surg Am 1992; 74: 448-454.
2. Ponseti IV. Congenital Clubfoot: Fundamentals of Treatment. 1996; 1st ed.
Oxford: Oxford University Press: 140.
3. Dobbs MB, Gurnett CA. Update on clubfoot: etiology and treatment. Clin Orthop Relat Res 2009; 467: 1146-1153.
4. Siapkara A, Duncan R. Congenital talipes equinovarus: a review of current management. J Bone Joint Surg Br 2007; 89: 995-1000.
5. Herzenberg JE, Radler C, Bor N. Ponseti versus traditional methods of casting for idiopathic clubfoot. J Pediatr Orthop 2002; 22: 517-521.
6. Ponseti IV, Smoley EN. Congenital club foot: the results of treatment. J Bone Joint Surg Am 1963; 45: 261-344.
7. Laaveg SJ, Ponseti IV. Long-term results of treatment of congenital club foot. J Bone Joint Surg Am 1980; 62: 23-31.
8. Bor N, Coplan JA, Herzenberg JE. Ponseti treatment for idiopathic
clubfoot: minimum 5-year followup Clin Orthop Relat Res 2009; 467: 1263-1270.
9. Barker SL, Lavy CB. Correlation of clinical and ultrasonographic findings after Achilles tenotomy in idiopathic club foot. J Bone Joint Surg Br 2006; 88: 377-379.
10. Maranho DA, Nogueira-Barbosa MH, Simão MN, Volpon JB. Ultrasonographic evaluation of Achilles tendon repair after percutaneous sectioning for the correction of congenital clubfoot residual equinus.J Pediatr Orthop 2009; 29: 804-10. |
