A NEW WAY OF SURGICAL CORRECTION OF LITTLE TOES DEFORMATION Leonova S.N., Usoltsev I.V.
Irkutsk Scientific Center of Surgery and Traumatology, Irkutsk, Russia
Hallux valgus is one of the most frequent deformations of toes [1, 2]. Among little fingers, the second one is more susceptible to deformation, other toes – more seldom [3]. With combination of hallux valgus and varus hammer second toe (crossed toes), patients suffer from even higher pain than in isolated deformation of a toe. It is associated with intense cosmetic defect, which do not allow selecting common or special footwear, sharply limits movement and communication. Moreover, patients suffer from pain relating to deformation, metatarsalgia and formation of callus and wounds.
Currently, there are lots of techniques for surgical correction of hallux valgus, but little amount of techniques is used for treatment of deformations of little toes [4, 5, 6]. Despite of achieved success in treatment of deformation of toes 2-4, it is still impossible to prevent such postsurgical complications as recurrent deformations, recurrent metatarsalgia, transient metatarsalgia, stiffness and contracture of metatarsophalangeal articulation and others [7, 8, 9].
According to our opinion, insufficient efficiency of the known techniques for surgical correction of deformation of little toes is related to absence of a substantiated approach to treatment of this pathology.
Objective – to offer a new technique for surgical treatment of varus hammer little toes and to estimate its efficiency.
MATERIALS AND METHODS
The analysis included the results of treatment of 27 patients with hallux valgus in combination with non-rigid varus hammer deformation of the second toe in Irkutsk Scientific Center of Surgery and Traumatology (orthopedic unit) in 2016-2018.
The study did not include the following patients: with deformation of the toes 3-5, at the age before 20 and older than 65, with planovalgus deformity, with foot elasticity of degree 3, with systemic diseases of connective tissue, with systemic osteoporosis and history of surgery for such foot pathology.
All patients were women at the age 20-65, mean age of 48.2 ± 12.38. The period of the disease was 20.5 ± 12.14 years (2-40 years). Egyptian foot was in 77.8 %.
The study was conducted in compliance with Ethical Principles for Medical Research with Human Subjects 2000, and the Rules for Clinical Practice in the Russian Federation confirmed by the Order of Russian Health Ministry on 19 June 2003, No.266.
The X-ray study was conducted for all patients before and after surgery. It was conducted with Agfa DX-D 300 in three planes (dorsoplantar, lateral), in standing position during statistical load, with 1 meter of focus distance.
The surgical treatment included the correction of deformation of the toes 1 and 2. All patients received the correction of valgus declination of the first toe with use of the own technique [10]. Two surgical techniques were used for correction of varus hammer deformation of the second toe. Therefore, the patients were distributed into two groups.
The first group included 17 patients who received the treatment with a well known method by Weil [4]. A longitudinal skin incision is made immediately over the second instep bone. The articular capsule and collateral ligaments are dissected. Then the toe is moved in plantar direction for optimal visualization of the metatarsal head. The plantar fragment of the instep bone is displaced proximally for required shortening. The shortening depended on the length of the instep bone and a degree of subluxation. Osteotomy was fixed with one screw.
The second group included 10 patients who received our surgical technique for correction of the second toe deformation. The technique is described below.
X-ray examination of the patient’s foot is conducted before surgery. A frontal X-ray image (in natural size) is used for estimation of length of required shortening of the instep bone and for required lateral displacement of the distal fragment of the instep bone in relation to its proximal fragment. In the X-ray image in the region of deformation, a line of longitudinal axis (3) of the instep bone (1) is drawn; the perpendiculars (6, 7) are drawn to this line: the first – through the end proximal point (4) of epiphysis of the main phalanx (2), the second one – through the end distal point (5) of distal epiphysis of the instep bone. The distance between the first perpendicular and the second one (6, 7) in the line of longitudinal axis (3) of the instep bone is the length of required shortening (8) of the instep bone (Fig. 1).
Figure 1
The scheme of estimation of length of required shortening of the instep bone: 1 – instep bone; 2 – main phalanx; 3 – longitudinal axis of instep bone; 4 – end proximal point of epiphysis of main phalanx; 5 – end distal point of distal epiphysis of instep bone; 6 – perpendicular to longitudinal axis of instep bone through end distal point of distal epiphysis of instep bone; 7 – perpendicular to longitudinal axis of instep bone through end proximal end of epiphysis of main phalanx, 8 – length of required shortening of instep bone between perpendicular lines 6 and 7.
Then two lines are drawn in parallel to the longitudinal axis (3): the first line – through the point of middle of articular surface of the metatarsal head (10); the second one – through the point of middle of articular surface of the base of the main phalanx (9). The size of required lateral displacement of the distal fragment of the instep bone in relation to the proximal fragment of the instep bone is estimated according to length of the perpendicular (13), which is drawn from the point of middle of articular surface of the metatarsal head to the contralateral parallel line (Fig. 2).
Figure 2
The scheme of estimation of required lateral displacement of distal fragment of instep bone in relation to proximal fragment: 9 – center of articular surface of the base of main phalanx; 10 – center of articular surface of instep bone head; 11 – line through point 9 in parallel to line of longitudinal bone of instep bone; 12 – line through point 10 in parallel to line of longitudinal axis of instep bone; 13 – distance of required lateral displacement of distal fragment of instep bone in relation to proximal fragment.
After estimation of required parameters for correction of deformation of toes, the surgical treatment is carried out. In aseptic conditions and under spinal anesthesia in supine position, the tourniquet is applied onto the lower one-third of the hip, and the dorsal direct plane incision (3 cm) is made over the distal one-third of the second instep bone. The wound borders are separated, the neck (14) and the distal diaphysis of the instep bone are separated, and periosteum is displaced laterally. After that, with use of the oscillating saw, osteotomy (15) of the instep bone (1) is conducted in the distal part of diaphysis in the frontal plane with angle of 60-70 degrees to its longitudinal axis (3), leaving 10 mm (16) from the neck of the instep bone (14), from dorsal surface to plantar surface of the instep bone in distal direction (Fig. 3).
Figure 3
The scheme of estimation of osteotomy line of instep bone: 14 – instep bone neck; 15 – osteotomy line of instep bone under angle 60-70 degrees to its longitudinal axis; 16 – distance from instep bone neck to osteotomy line 15 of instep bone.
A rasparatory is used for separating the osteotomy fragments of the instep bone. The proximal fragment is drawn to the wound.
Two crossing lines are drawn in the distal part of the proximal fragment of the instep bone: the first line is drawn in parallel to the osteotomy plane (15), leaving the distance required for shortening (8) from the distal border of the proximal fragment. The second line (18) is drawn perpendicularly to the first one, beginning from the distal border of the proximal fragment, leaving the distance required for necessary lateral displacement from the lateral surface of the instep bone (13) (Fig. 4a).
Then a step-shaped ledge (19), which appears after marking between two lines (17, 18), is sawn from medial side of the distal part of the proximal fragment of the instep bone, resulting in a lateral ledge from the lateral side of the distal part of the proximal fragment of the instep bone (Fig. 4b).
The proximal lateral angle of the distal fragment of the instep bone is drawn behind the saw cut of the formed lateral ledge, and the compression is conducted along the axis of the instep bone up to full contact between its fragments (20) (Fig. 4c).
Figure 4
The scheme of formation of step-shaped jove on proximal fragment of instep bone, apposition and fixation of osteotomy fragments:
a) osteotomy plane and transecting lines in distal part of proximal fragment of instep bone: 17 – line in parallel to osteotomy plane (15) of instep bone; 18 – line perpendicular to line 17, beginning from distal end of proximal fragment of instep bone;
b) step-shaped jove of distal part of proximal and distal fragments of instep bone after compression (19);
c) final position of proximal and distal fragments of instep bone after compression (20);
d) osteosynthesis of matched fragments of instep bone and screw fixation (21).
The fragments of the instep bone are fixed with the cannulated screw (21) in oblique direction from the head to the wall of the instep bone diaphysis (Fig. 4d).
After surgery, all patients used the orthopedic shoes from the first day.
The results of surgical treatment were estimated in all patients after surgery and 6 months after it.
The statistical analysis of the results was conducted with Statistica 10.0. The groups were estimated for mean arithmetic (M) and standard deviation (± SD). Student’s test was used for comparative analysis of quantitative data. P value < 0.05 was considered as statistically significant.
RESULTS
For all 27 patients, the intervention for the first ray completely corrected the valgus declination of the first toe without loss of correction and recurrence of the disease.
Weil’s technique was used for correction of varus hammer deformation of the second toe in 17 patients in the first group. Weil’s osteotomy for the second toe was used in combination with lengthening the tendon of long extensor of the second toe that allowed extension of the second toe in all 17 patients, i.e. achieving some kind of correction of hammer-shaped deformation. However postsurgical clinical estimation identified a visually raised position of the main phalanx (dorsal declination) in 5 cases. X-ray images showed a dorsal subluxation in the metatarsophalangeal articulation in 10 patients. 12 patients (70.6 %) showed a medial declination (varus) of the second toe, with X-ray images showing a subluxation of the main phalanx in horizontal plane. Taping was used for correction of these defects of the second toe in the postsurgical period. Other 5 patients (29.4 %) visually showed a direct position of the second toe, i.e. achievement of correction of varus deformation, but X-ray image showed a medial subluxation of the main phalanx.
Six months after surgery, the clinical and radiological examination showed a medial subluxation in the metatarsophalangeal articulation in all 17 patients, varus declination of the second toe in 12 patients, dorsal subluxation in 10 patients, dorsal declination of a toe in 5 patients. Pain in the anterior part of the foot persisted in 14 patients, including 10 with rare moderate pain, 4 patients with daily intense pain in the second metatarsophalangeal articulation. 7 patients showed hyperkeratosis on the plantar surface in the plane of the head of the second instep bone. 5 cases showed transient metatarsalgia in the subhead space of the third instep bone. 11 patients complained on limited physical activity in different modes of load. 12 (70.6 %) of 17 patients were satisfied with result of the treatment.
10 patients (the group 2) were operated with the offered technique. No additional interventions were used for tendons in this group. Immediately after surgery, clinical and radiological estimation of the treatment results showed that all patients could extend and straighten the second toe, i.e. they achieved the correction of hammer and varus deformation of the second toe. Subluxation in the second metatarsophalangeal articulation was treated, congruity of articular surfaces of the metatarsal head and the base of the main phalanx was restored.
During 6 months of follow-up, 3 patients showed a rare, moderate pain syndrome in the second metatarsophalangeal articulation. Other patients did not suffer from pain. Hyperkeratosis was treated. The clinical and radiologic data did not show any subluxation in the metatarsophalangeal articulation, varus or dorsal declination of the second toe in all 10 patients. One case showed a transient metatarsalgia in subcapital space of the third instep bone. Two patients complained of limited physical activity during excessive load. All patients were satisfied with the results of surgical treatment, with high improvement in appearance of the foot, its functioning and possibility of wearing the common footwear.
In the patients of both groups, the postsurgical wounds healed without complications in all cases, with satisfactory union of bone tissue after osteotomy.
The comparative analysis of the surgical treatment results of varus hammer deformation of the second toe showed the advantages of this technique in two groups of the patients (the table).
Table
Comparative estimation of incidence of values of poor outcomes of surgical treatment in patients of both groups with varus hammer deformation of the second toe 6 months after surgery (n = 27)
|
Value |
Incidence |
|||
|
Group 1 (n = 17) |
Group 2 (n = 10) |
|||
|
Abs. n. |
% |
Abs. n. |
% |
|
|
Persistent pain |
14 |
82.5 |
3 |
30 |
|
Hyperkeratosis on plantar surface |
7 |
41.2 |
0 |
0 |
|
Limited physical activity |
11 |
64.7 |
2 |
20 |
|
Dorsal subluxation in 2nd metatarsophalangeal articulation |
10 |
58.8 |
0 |
0 |
|
Subluxation in metatarsophalangeal articulation in horizontal plane |
17 |
100 |
0 |
0 |
|
Dorsal declination of 2nd toe |
5 |
29.4 |
0 |
0 |
|
Varus declination of 2nd toe |
12 |
70.6 |
0 |
0 |
|
Transitional metatarsalgia |
5 |
29.4 |
1 |
10 |
|
Ì ± SD |
10 ± 4.56* |
|
0.5 ± 0.84 |
|
Note: * – reliable differences between groups according to Student’s test with p < 0.01.
A statistically significant 20-fold decrease in the incidence of the analyzed values and the minimal amount of their manifestations in the second group present the evidence of higher efficiency of the offered technique in comparison with the known technique.
So, the use of the well known treatment technique resulted in persistence of pain in the anterior foot in most patients, as well as varus declination of the second toe, subluxation in the metatarsophalangeal articulation, limited physical activity that supposed insufficient correction of hammer and, to higher degree, varus deformation of the second toe.
The use of the offered technique completely corrected hammer and varus deformation of the second toe, subluxation in the metatarsophalangeal articulation, hyperkeratosis on plantar surface; it restored physical activity in 80 % of the patients, corrected pain in 70 %, i.e. improved the treatment results. Despite of the advantages of the offered technique, we did not find any reliable differences in amount of the patients who were satisfied with the treatment outcome, but it could be related to the basic severity of deformation.
We present a clinical case of a patient who received the surgical treatment with the offered technique. The patient gave her informed consent for publication of the clinical case.
Clinical case
The patient D., female, age of 69, addressed to the clinic of Irkutsk Scientific Center of Surgery and Traumatology. She complained of evident deformation of the left toes 1 and 2, plantar callosity, sharp pain on plantar surface in the place of the head of the second instep bone, impossibility of selecting and wearing footwear, and absence of appropriate use of the left foot.
The patient was examined. X-ray examination was conducted (Fig. 5a, b, c).
Figure 5a
The patient D., female, age of 69. The photo of left foot before surgery: top view
Figure 5b
The patient D., female, age of 69. The photo of left foot before surgery: frontal view
Figure 5c
The patient D., female, age of 69. The photo of left foot before surgery: frontal view X-ray image.
The main diagnosis was: “Transverse longitudinal platypodia of degree 2-3 to the left. Valgus declination of the first left toe, varus hammer deformation of the second left toe. Metatarsalgia”.
The X-ray image was used for calculation of the size of required shortening and lateral displacement of the second instep bone – 4 and 3 mm correspondingly. Surgical treatment was initiated with correction of the first toe deformation. The second toe deformation was corrected with use of the offered technique (Fig. 6a, b, c).
Figure 6a
The patient D., female, age of 69. The photo of left foot after surgery: top view
Figure 6b
The patient D., female, age of 69. The photo of left foot after surgery: frontal view
Figure 6c
The patient D., female, age of 69. The photo of left foot after surgery: frontal view X-ray image.
After surgery, the patient could move while wearing the orthopedic shoe on her left foot during 4 weeks. She visited control examinations.
After 6 months, the control examination showed: absence of complaints; she was satisfied with treatment outcome; no metatarsalgia; complete correction of deformation of the toes 1 and 2 (Fig. 7a, b, c).
Figure 7a
The patient D., female, age of 69. The photo of left foot 6 months after surgery: top view
Figure 7b
The patient D., female, age of 69. The photo of left foot 6 months after surgery: frontal view
Figure 7c
The patient D., female, age of 69. The photo of left foot 6 months after surgery: frontal view X-ray image.
The use of the offered surgical technique allowed correction of valgus declination of the first toe and varus hammer deformation of the second toe of the left foot.
DISCUSSION
The results show the low efficiency of Weil’s technique for correction of varus hammer deformation of little toes. This technique includes realization of radical release of the metatarsophalangeal articulation with dissection of contralateral ligaments, resulting in its destabilizing. It promotes the condition with preservation of dorsal subluxation of the main phalanx; the toe tries to come to elevated position over the support or to come back to hammer shape. Moreover, realization of traumatic intraarticular intervention for the metatarsophalangeal articulation can cause contractures and/or stiffness of joints in 10-20 % of patients [8] and pain syndrome.
The classic technique by Weil includes the shortening of the instep bone with displacement of its head proximally for correction of hammer toe. Correction of varus deformation requires realization of lateral displacement of a fragment of the instep bone that is not provided in Weil’s technique. Therefore, the use of the technique does not correct varus toe and can be efficient only for hammer deformation.
The offered surgical technique used the new substantiated approaches, preliminary calculations and methods which had removed hammer and varus deformations.
Preliminary estimation of X-ray image of the foot using such parameters as length of required shortening and lateral displacement of the distal fragment of the instep bone in relation to its proximal fragment allows considering the individual features of deformation of toes in each patient, and, during surgery, to conduct precise lining in distal part of the proximal fragment of the instep bone, and, using these lines, to make saw cuts for correct removal of deformation of toes, recovery of anatomical condition of and static-dynamic function of the foot without recurrent events in the postsurgical period.
Osteotomy of the instep bone is conducted in the distal part of diaphysis at angle of 60-70 degrees to its horizontal axis, leaving 10 mm from the neck of the instep bone for the reason that osteotomy plane will pass only in the region of diaphysis, without injury to the head of the instep bone and subcapital space. As result, apposition of diaphysis of the proximal fragment and diaphysis of the distal fragment of the instep bone gives maximal preservation of regenerative potential of bone fragments and nutrition of the instep bone head. The square of contact between fragments of osteotomy at angle of 60-70 degrees is sufficient for stable fixation and successful union of the instep bone fragments.
Conduction of two crossing lines in the distal part of the proximal fragment of the instep bone before osteotomy allows precise estimation of distance required for shortening of the instep bone, for extending the flexed toe, and distance for medial displacement of the distal fragment of the instep bone for recovery of anatomical location of the articular surface of the instep bone head and articular surface of the base of the main phalanx, with achievement of congruity in the metatarsophalangeal articulation. Achievement of congruity in the metatarsophalangeal articulation and sparing intervention for the joint provide the restoration of movement in the joint, prevention of subsequent contractures and joint stiffness.
The square-shaped ledge allows easier and more precise intake of proximal lateral angle of the distal fragment of the instep bone for full contact between proximal and distal fragments of the instep bone, to intensify the rigidity of fixation of proximal and distal fragments of the instep bone, to properly stabilize the distal fragment in relation to the proximal one.
Displacement of the distal fragment of the instep bone in targeted direction discharges the subcapital space, gets the instep bone head out of load from body weight and eliminates pain in metatarsalgia.
The use of the offered technique promotes successful correction of both types of toe deformation: varus and hammer. Surgical treatment the offered technique corrects a cosmetic defect and pain, restores the normal function of the foot and provides a possibility for wearing common footwear.
CONCLUSION
The offered surgical technique for treatment of deformation of little toes provides more precise correction of varus hammer deformation by means of preliminary calculated required shortening and displacement of the instep bone with consideration of individual features of foot condition, recovery of congruity of articular surfaces of the metatarsophalangeal articulation, decreases the risk of postsurgical recurrent deformations of toes and metatarsalgia, i.e. it is clinically efficient.
Information on financing and conflict of interests
The study was conducted without sponsorship.
The authors declare the absence of any clear or potential conflicts of interests relating to publication of this article.