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The fifth metatarsal rotational osteotomy for the correction of tailor’s bunion deformity
The Foot 13 (2003) 190–195
The fifth metatarsal rotational osteotomy for the correction of tailor’s bunion deformity P. Bewick∗ , T.E. Kilmartin Department of Podiatric Surgery, Carlton Health Clinic, 61 Burton Road, Carlton, Nottingham NG4 3DQ, UK Received 1 November 2002; accepted 14 January 2003
Abstract Twenty patients with a mean age of 45 (range = 16–77) underwent tailor’s bunion correction using a rotational osteotomy of the fifth metatarsal. The fourth/fifth intermetatarsal angle was measured with weight bearing dorsiplantar radiographs pre-operatively and at an average of 27 months post-operatively. The American Orthopedic Foot and Ankle Society (AOFAS) clinical rating system was also applied pre-operatively and at an average of 27 months post-operatively. X-ray review revealed a mean pre-operative angle of 10.0◦ and mean post-operative angle of 6.3◦ (P = 0.0001), mean pre-operative AOFAS score = 50.2, mean post-operative score = 92.8 (P = 0.0001). No transfer metatarsalgia was noted at final review, and all osteotomies proceeded to union. All patients stated that they were satisfied with the outcome of surgery. © 2003 Elsevier Ltd. All rights reserved. Keywords: Rotational osteotomy; Intermetatarsal angle; Metatarso-phalangeal joint
1. Introduction
2. Surgical technique
Both distal and basal procedures for the correction of tailor’s bunion have been described in the literature. Osteotomies of the fifth metatarsal are not without their limitations and complications however. Distal transpositional osteotomies are more commonly reported, but offer limited transverse plane correction and reported complications include recurrence and transfer lesions. Delayed and non-union may be a concern with these procedures, and lengthy post-operative immobilization is often required. The fifth metatarsal rotational osteotomy as originally demonstrated by Sigvard T. Hansen and alluded to by Kilmartin [1], offers correction of the intermetatarsal angle which is not limited by metatarsal width. The oblique nature of the osteotomy offers a high surface area of bone to bone contact and stability, which combined with its location in the metaphysis should minimize the risk of non-union, and allow early mobilization.
The procedure is illustrated in principle in Fig. 1. Exposure of the dorsal and lateral aspects of the fifth metatarsal is achieved through a lateral incision extending from the base of the proximal phalanx to the mid-shaft of the metatarsal. The lateral eminence is removed with an oscillating saw and a smooth 0.045 K-wire is inserted into the lateral aspect of the metatarsal head at a point just proximal to the articular cartilage one-third of the distance from the dorsal cortex to act as a guide wire; sagittal plane correction is determined by the angle of insertion of the wire. An osteotomy guide is then applied to the guide wire and an oscillating saw is used to perform a longitudinal cut while leaving the dorsal and plantar cortices intact (Fig. 2). A 1.5 mm drill hole is then made through both cortices, countersunk, and a 2.0 mm cortical screw inserted to finger tightness (Fig. 3). The longitudinal cut is then extended through the dorsal cortex, and the osteotomy is completed through the plantar cortex with a transverse cut which is performed in a proximal lateral to distal medial direction. The 2.0 mm screw acts as a pivot to rotate the capital fragment of the fifth metatarsal back into the foot, thus, reducing
∗ Corresponding author. Tel.: +44-115-9617616; fax: +44-115-961-3268. E-mail address: [email protected] (P. Bewick).
0958-2592/$ – see front matter © 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0958-2592(03)00009-9
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
191
Fig. 1. The fifth metatarsal rotational osteotomy.
the intermetatarsal angle (Fig. 4). The screw is tightened once the desired correction is achieved, and excess bone created by the rotation is removed with an oscillating saw.
2.1. Post-operative regimen A bulky dressing and post-operative shoe were applied and patients ambulated with crutches for 2 weeks.
Fig. 2. A longitudinal cut is performed leaving the dorsal and plantar cortices intact.
192
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
Fig. 3. A 2.0 mm cortical screw is inserted to finger tightness to act as a pivot for rotation of the capital fragment.
The dressing was changed at one week and removed at 2 weeks post-operatively, at which point all patients were able to return to accommodative footwear (e.g. training shoes).
2.2. Patients and method Between 1996 and 1999, 22 rotational osteotomies were performed upon 20 patients for the correction of tailor’s
Fig. 4. Radiographic correction of the fourth/fifth intermetatarsal angle (before and after).
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
193
Table 1 Pre- and post-operative IM angles and AOFAS scores Patient
Age
Gender
L/R Foot
Pre-operative IM angle (◦ )
IM angle at 27 months (◦ )
Pre-operative AOFAS
AOFAS at 27 months
1 2 3
77 70 68
Male Female Female Male Male Male Male Female Female Female Female Female Male Female
54 62 54 44 38 49 40 47 63 60 53
90 100 100 100 95 90 83 73 90 100 100
15 16 17 18 19 20
46 16 16 34 47 23
Female Male Male Female Female Male
8 6 4 4 7.5 6 8 7 7 5 5.5 6.5 7 7 7 7 6 7 5 4 4.5 4
80 100 100
23 19 58 54 69 50 42 31 63 22 69
10 7 4 4 14 16 13 11 8 13 11 10 9 10 11 13.5 11 10 10 8 7 7.5
60 29 32
4 5 6 7 8 9 10 11 12 13 14
R R R L L L L L L L R L L L R L L R L R L R
39 62 47 60 57 62
100 88 92 100 90 85
bunion deformity. The procedures were performed by two different surgeons who were equally experienced in performing the procedure in three surgical centers. Surgeon ‘A’ performed the procedure upon patients 1–7 (see Table 1) and surgeon ‘B’ operated upon patients 8–20. There were 9 male and 11 female patients with a mean age of 45 (range 16–77). The pre-operative fourth/fifth intermetatarsal (IM) angle was measured by Bewick on dorsi-plantar weight bearing radiographs from the bisection of lines drawn within each metatarsal connecting the center of the articular surface of the metatarsal head with the center of the proximal articulation as originally described by Mitchell et al. [2], and recommended by Schneider et al. [3] for evaluation of the IM angle in hallux valgus (Fig. 5). The American Orthopedic Foot and Ankle Society (AOFAS) clinical rating system (Fig. 6), which is considered by the authors to be a comprehensive scoring system, was applied to each patient pre-operatively by surgeons ‘A’ and ‘B’. The fourth/fifth intermetatarsal angles were then measured, and the AOFAS system reassessed at an average of 27 months post-operatively. Patients were also asked to give their opinion as to whether they were satisfied, satisfied with reservations or dissatisfied with the results of their surgery at final review.
Fig. 5. Method for determining fourth/fifth intermetatarsal angle on dorsiplantar weight bearing X-ray.
3. Results Pre- and post-operative IM angles and AOFAS clinical rating scores were compared for each patients and are presented in Table 1.
Table 2 Statistical significance between pre- and post-operative IM angles, and AOFAS scores
Mean value Standard deviation Range Statistical significance (paired t-test)
Pre-operative IM angle
IM angle at 27 months
Pre-operative AOFAS
10◦
6.3◦
50.6 92.8 10.7 14.6 29–63 73–100 P = 0.0001 (highly statistically significant)
2.8 2.2 4–16 4–9 P = 0.0001 (highly statistically significant)
AOFAS at 27 months
194
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
Lesser Metatarso-phalangeal-Interphalangeal Scale (Total =100 points) Pain None
40
Mild, occasional
30
Moderate, daily
20
Severe, almost always present
10
Function
The distribution of this data appeared to be normal and a paired t-test was, therefore, applied which revealed that the difference between pre- and post-operative IM angles and AOFAS scores was highly statistically significant (Table 2). The mean IM angle was reduced by 3.7◦ , from 10.0◦ pre-operatively to 6.7◦ post-operatively, and the mean AOFAS score increased by 42.2 points, from 50.6 points pre-operatively to 92.8 points post-operatively. All patients stated that they were satisfied with the result of their surgery at final review.
Activity limitations No limitations
10
4. Complications
Limitation of recreational activities
7
Limited daily and recreational activities
4
Severe limitation of daily and recreational activities
0
Footwear requirements Fashionable conventional shoes, no insert required
10
Comfort footwear, shoe insert
5
Modified shoe
0
5. Discussion
MTP joint motion (Dorsiflexion plus plantarflexion) Normal or mild restriction (75 degrees or more)
10
Moderate restriction (30-74 degrees)
5
Severe restriction (Less than 10 degrees)
0
IP joint motion (Plantarflexion) No restriction
5
Severe restriction (Less than 10 degrees)
0
MTP-IP stability (All directions) Stable
5
Definitely unstable or able to dislocate
0
Callus No callus or asymptomatic callus
5
Symptomatic callus
0
Alignment Good, lesser toe well aligned Fair, some degree of lesser toe malalignment, no symptoms Poor, severe malalignment, symptoms
Seventy-five percent of patients were complication free while 25% reported the following: One patient developed retraction of the fifth toe with resultant irritation from footwear. One patient complained of stiffness of the fifth metatarso-phalangeal joint which appeared to be due to post-surgical gout. Three patients complained of mild occasional pain in the fifth metatarso-phalangeal joint at final review.
15 10 0
Fig. 6. The American Orthopedic Foot and Ankle Society Clinical Rating Scale used pre-operatively and at final follow-up.
As noted by Benson [4], there is a paucity of literature on the subject of tailor’s bunion in comparison to hallux valgus but this by no means detracts from the fact that tailor’s bunion can be very symptomatic, leading to metatarsophalangeal joint pain, footwear irritation, skin lesions and associated adducto-varus deformity of the fifth toe. A variety of distal procedures have been devised to correct tailor’s bunion, with varying degrees of success. Keating et al. [5] reported a 56% success rate with the reverse Wilson procedure, but 76% of patients developed transfer lesions when the procedure was unfixated. A distal chevron procedure was employed by Kitaoka et al. [6] in 13 patients with good results (one case of transfer metatarsalgia, one infection). Konradsen et al. [7] reported a 78% success rate with the Hohmann–Thomasen procedure performed in 54 feet (36 patients). Six percent of patients experienced recurrence of the deformity, 10% developed transfer lesions, 4% developed intractable plantar keratosis and 2% had ‘operative’ complications. A limitation of distal procedures is that the capital fragment can only be transposed by a maximum of 50% of the metatarsal width before inviting instability, fourth/fifth intermetatarsal angle correction is therefore limited by metatarsal width at the distal metaphysis. In the 22 metatarsals involved in this study, the mean width of the metatarsal at the distal metaphysis measured on X-ray was 10.65 mm (range = 9.2–12.4 mm) and the mean length from base to distal metaphysis was 57.5 mm (range = 55.2–61.5 mm). As the capital fragment can only be transposed by 50% of the metatarsal width i.e. 10.65/2 = 5.33 mm in the ‘average metatarsal’ in this study, simple
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
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(1) It is capable of correcting fourth/fifth intermetatarsal angles of up to 16◦ . (2) In our experience it is not associated with the complications of transfer metatarsalgia or non-union. (3) It is a stable osteotomy amenable to internal fixation, allowing early mobilization.
Fig. 7. Calculation of fourth/fifth intermetatarsal angle correction available using a distal osteotomy in the ‘Average’ fifth metatarsal.
trigonometry can be used to calculate that the maximum intermetatarsal angle correction available using a distal procedure, which in the average fifth metatarsal would be 5◦ (Fig. 7). Trepal [8], on review of the literature, found that tailor’s bunion tends to become symptomatic at a fourth/fifth intermetatarsal angle of approximately 9◦ . Based on Trepal’s findings, one of the aims of tailor’s bunion correction, therefore, should be to reduce the fourth/fifth intermetatarsal angle to below 9◦ . As distal procedures are only capable of reducing the fourth/fifth intermetatarsal angle by 5◦ . It follows, therefore, that distal procedures would be unsuitable for correcting intermetatarsal angles exceeding 13◦ in this cohort. Five patients in this study group presented with fourth/fifth intermetatarsal angles of 13◦ or greater. The intermetatarsal angle was reduced to below 9◦ in all of these patients at final review. The rotational osteotomy would therefore appear to exceed the capabilities of distal procedures in terms of IM angle reduction. Basal osteotomy may be used to correct large intermetatarsal angles. Diebold [9] reports good results using a basal chevron procedure, with the mean fourth/fifth intermetatarsal angle being reduced from 12.1 to 1.3◦ in 20 patients (22 feet). Patients were required to ambulate in a special post-operative shoe for 6 weeks to prevent weight bearing upon the forefoot. There were three cases of delayed union which resolved within 6 months. One possible criticism of this study is that X-rays were not obtained at 8 weeks post-operatively when the patients were discharged, to assess the possibility of delayed union. This study was retrospective, and it was not the policy of either of the two surgeons involved to obtain X-rays at patient discharge. Patients were advised however to contact should they have any concerns, and no patients in this study related a history consistent with symptomatic delayed union. The advantages of the rotational osteotomy appear to be three-fold:
All patients in this study were able to walk in normal footwear 2 weeks post-operatively. The reported complications of mild occasional pain in the fifth metatarso-phalangeal joint in three patients, and of retraction of the fifth toe in one patient may be due post-operative fibrosis of the joint. This may suggest that fifth metatarso-phalangeal joint range of motion exercises should be instigated post-operatively. 6. Conclusion The rotational osteotomy appears to be a successful procedure for the correction of tailor’s bunion deformity, and compares favourably with other procedures described in the literature. 75% of patients were complication free and 100% of patients stated that they were satisfied with the outcome of this procedure at an average of 27 months postoperatively.
Acknowledgements The authors would like to thank Mr. A. Wilkinson FpodA FCPodS for his help in this study.
References [1] Kilmartin TE. Distal lesser metatarsal osteotomies: a review of surgical techniques designed to avoid non-union and minimize transfer metatarsalgia. Foot 1998;8(4):186–92. [2] Mitchell CL, et al. Osteotomy-bunionectomy for hallux valgus. J Bone Joint Surg 1958;40A:41–60. [3] Schneider W, et al. Metatarsohalangeal and intermetatarsal angle: different values and interpretataion of postoperative results Dependent on the technique of measurement. Foot Ankle Intern 1998;19(8): 532–6. [4] Benson M. A review of tailor’s bunion with an emphasis on surgical options. Internet reference: http://www.curtin.edu.au/curtin/dept/ physio/podiatry/encyclopedia/benson/. [5] Keating S, et al. Oblique fifth metatarsal osteotomy: a follow up study. J Foot Surg 1982;21:104–7. [6] Kitaoka HB, et al. Distal chevron metatarsal osteotomy for bunionette. Foot Ankle 1991;12(2):80–5. [7] Konradsen L, et al. Distal metatarsal osteotomy for bunionette deformity. J Foot Surg 1988;27(6):493–6. [8] Trepal M. Surgery of the fifth ray. In: McGlamry ED et al, editors. Comprehensive textbook of foot surgery, chapter 13, 2nd ed. London: Williams and Wilkins; 1992. p. 382. [9] Diebold PF. Basal Osteotomy of the Fifth Metatarsal for the Bunionette. Foot and Ankle 1991;12(2):74–9.
The fifth metatarsal rotational osteotomy for the correction of tailor’s bunion deformity P. Bewick∗ , T.E. Kilmartin Department of Podiatric Surgery, Carlton Health Clinic, 61 Burton Road, Carlton, Nottingham NG4 3DQ, UK Received 1 November 2002; accepted 14 January 2003
Abstract Twenty patients with a mean age of 45 (range = 16–77) underwent tailor’s bunion correction using a rotational osteotomy of the fifth metatarsal. The fourth/fifth intermetatarsal angle was measured with weight bearing dorsiplantar radiographs pre-operatively and at an average of 27 months post-operatively. The American Orthopedic Foot and Ankle Society (AOFAS) clinical rating system was also applied pre-operatively and at an average of 27 months post-operatively. X-ray review revealed a mean pre-operative angle of 10.0◦ and mean post-operative angle of 6.3◦ (P = 0.0001), mean pre-operative AOFAS score = 50.2, mean post-operative score = 92.8 (P = 0.0001). No transfer metatarsalgia was noted at final review, and all osteotomies proceeded to union. All patients stated that they were satisfied with the outcome of surgery. © 2003 Elsevier Ltd. All rights reserved. Keywords: Rotational osteotomy; Intermetatarsal angle; Metatarso-phalangeal joint
1. Introduction
2. Surgical technique
Both distal and basal procedures for the correction of tailor’s bunion have been described in the literature. Osteotomies of the fifth metatarsal are not without their limitations and complications however. Distal transpositional osteotomies are more commonly reported, but offer limited transverse plane correction and reported complications include recurrence and transfer lesions. Delayed and non-union may be a concern with these procedures, and lengthy post-operative immobilization is often required. The fifth metatarsal rotational osteotomy as originally demonstrated by Sigvard T. Hansen and alluded to by Kilmartin [1], offers correction of the intermetatarsal angle which is not limited by metatarsal width. The oblique nature of the osteotomy offers a high surface area of bone to bone contact and stability, which combined with its location in the metaphysis should minimize the risk of non-union, and allow early mobilization.
The procedure is illustrated in principle in Fig. 1. Exposure of the dorsal and lateral aspects of the fifth metatarsal is achieved through a lateral incision extending from the base of the proximal phalanx to the mid-shaft of the metatarsal. The lateral eminence is removed with an oscillating saw and a smooth 0.045 K-wire is inserted into the lateral aspect of the metatarsal head at a point just proximal to the articular cartilage one-third of the distance from the dorsal cortex to act as a guide wire; sagittal plane correction is determined by the angle of insertion of the wire. An osteotomy guide is then applied to the guide wire and an oscillating saw is used to perform a longitudinal cut while leaving the dorsal and plantar cortices intact (Fig. 2). A 1.5 mm drill hole is then made through both cortices, countersunk, and a 2.0 mm cortical screw inserted to finger tightness (Fig. 3). The longitudinal cut is then extended through the dorsal cortex, and the osteotomy is completed through the plantar cortex with a transverse cut which is performed in a proximal lateral to distal medial direction. The 2.0 mm screw acts as a pivot to rotate the capital fragment of the fifth metatarsal back into the foot, thus, reducing
∗ Corresponding author. Tel.: +44-115-9617616; fax: +44-115-961-3268. E-mail address: [email protected] (P. Bewick).
0958-2592/$ – see front matter © 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0958-2592(03)00009-9
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
191
Fig. 1. The fifth metatarsal rotational osteotomy.
the intermetatarsal angle (Fig. 4). The screw is tightened once the desired correction is achieved, and excess bone created by the rotation is removed with an oscillating saw.
2.1. Post-operative regimen A bulky dressing and post-operative shoe were applied and patients ambulated with crutches for 2 weeks.
Fig. 2. A longitudinal cut is performed leaving the dorsal and plantar cortices intact.
192
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
Fig. 3. A 2.0 mm cortical screw is inserted to finger tightness to act as a pivot for rotation of the capital fragment.
The dressing was changed at one week and removed at 2 weeks post-operatively, at which point all patients were able to return to accommodative footwear (e.g. training shoes).
2.2. Patients and method Between 1996 and 1999, 22 rotational osteotomies were performed upon 20 patients for the correction of tailor’s
Fig. 4. Radiographic correction of the fourth/fifth intermetatarsal angle (before and after).
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
193
Table 1 Pre- and post-operative IM angles and AOFAS scores Patient
Age
Gender
L/R Foot
Pre-operative IM angle (◦ )
IM angle at 27 months (◦ )
Pre-operative AOFAS
AOFAS at 27 months
1 2 3
77 70 68
Male Female Female Male Male Male Male Female Female Female Female Female Male Female
54 62 54 44 38 49 40 47 63 60 53
90 100 100 100 95 90 83 73 90 100 100
15 16 17 18 19 20
46 16 16 34 47 23
Female Male Male Female Female Male
8 6 4 4 7.5 6 8 7 7 5 5.5 6.5 7 7 7 7 6 7 5 4 4.5 4
80 100 100
23 19 58 54 69 50 42 31 63 22 69
10 7 4 4 14 16 13 11 8 13 11 10 9 10 11 13.5 11 10 10 8 7 7.5
60 29 32
4 5 6 7 8 9 10 11 12 13 14
R R R L L L L L L L R L L L R L L R L R L R
39 62 47 60 57 62
100 88 92 100 90 85
bunion deformity. The procedures were performed by two different surgeons who were equally experienced in performing the procedure in three surgical centers. Surgeon ‘A’ performed the procedure upon patients 1–7 (see Table 1) and surgeon ‘B’ operated upon patients 8–20. There were 9 male and 11 female patients with a mean age of 45 (range 16–77). The pre-operative fourth/fifth intermetatarsal (IM) angle was measured by Bewick on dorsi-plantar weight bearing radiographs from the bisection of lines drawn within each metatarsal connecting the center of the articular surface of the metatarsal head with the center of the proximal articulation as originally described by Mitchell et al. [2], and recommended by Schneider et al. [3] for evaluation of the IM angle in hallux valgus (Fig. 5). The American Orthopedic Foot and Ankle Society (AOFAS) clinical rating system (Fig. 6), which is considered by the authors to be a comprehensive scoring system, was applied to each patient pre-operatively by surgeons ‘A’ and ‘B’. The fourth/fifth intermetatarsal angles were then measured, and the AOFAS system reassessed at an average of 27 months post-operatively. Patients were also asked to give their opinion as to whether they were satisfied, satisfied with reservations or dissatisfied with the results of their surgery at final review.
Fig. 5. Method for determining fourth/fifth intermetatarsal angle on dorsiplantar weight bearing X-ray.
3. Results Pre- and post-operative IM angles and AOFAS clinical rating scores were compared for each patients and are presented in Table 1.
Table 2 Statistical significance between pre- and post-operative IM angles, and AOFAS scores
Mean value Standard deviation Range Statistical significance (paired t-test)
Pre-operative IM angle
IM angle at 27 months
Pre-operative AOFAS
10◦
6.3◦
50.6 92.8 10.7 14.6 29–63 73–100 P = 0.0001 (highly statistically significant)
2.8 2.2 4–16 4–9 P = 0.0001 (highly statistically significant)
AOFAS at 27 months
194
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
Lesser Metatarso-phalangeal-Interphalangeal Scale (Total =100 points) Pain None
40
Mild, occasional
30
Moderate, daily
20
Severe, almost always present
10
Function
The distribution of this data appeared to be normal and a paired t-test was, therefore, applied which revealed that the difference between pre- and post-operative IM angles and AOFAS scores was highly statistically significant (Table 2). The mean IM angle was reduced by 3.7◦ , from 10.0◦ pre-operatively to 6.7◦ post-operatively, and the mean AOFAS score increased by 42.2 points, from 50.6 points pre-operatively to 92.8 points post-operatively. All patients stated that they were satisfied with the result of their surgery at final review.
Activity limitations No limitations
10
4. Complications
Limitation of recreational activities
7
Limited daily and recreational activities
4
Severe limitation of daily and recreational activities
0
Footwear requirements Fashionable conventional shoes, no insert required
10
Comfort footwear, shoe insert
5
Modified shoe
0
5. Discussion
MTP joint motion (Dorsiflexion plus plantarflexion) Normal or mild restriction (75 degrees or more)
10
Moderate restriction (30-74 degrees)
5
Severe restriction (Less than 10 degrees)
0
IP joint motion (Plantarflexion) No restriction
5
Severe restriction (Less than 10 degrees)
0
MTP-IP stability (All directions) Stable
5
Definitely unstable or able to dislocate
0
Callus No callus or asymptomatic callus
5
Symptomatic callus
0
Alignment Good, lesser toe well aligned Fair, some degree of lesser toe malalignment, no symptoms Poor, severe malalignment, symptoms
Seventy-five percent of patients were complication free while 25% reported the following: One patient developed retraction of the fifth toe with resultant irritation from footwear. One patient complained of stiffness of the fifth metatarso-phalangeal joint which appeared to be due to post-surgical gout. Three patients complained of mild occasional pain in the fifth metatarso-phalangeal joint at final review.
15 10 0
Fig. 6. The American Orthopedic Foot and Ankle Society Clinical Rating Scale used pre-operatively and at final follow-up.
As noted by Benson [4], there is a paucity of literature on the subject of tailor’s bunion in comparison to hallux valgus but this by no means detracts from the fact that tailor’s bunion can be very symptomatic, leading to metatarsophalangeal joint pain, footwear irritation, skin lesions and associated adducto-varus deformity of the fifth toe. A variety of distal procedures have been devised to correct tailor’s bunion, with varying degrees of success. Keating et al. [5] reported a 56% success rate with the reverse Wilson procedure, but 76% of patients developed transfer lesions when the procedure was unfixated. A distal chevron procedure was employed by Kitaoka et al. [6] in 13 patients with good results (one case of transfer metatarsalgia, one infection). Konradsen et al. [7] reported a 78% success rate with the Hohmann–Thomasen procedure performed in 54 feet (36 patients). Six percent of patients experienced recurrence of the deformity, 10% developed transfer lesions, 4% developed intractable plantar keratosis and 2% had ‘operative’ complications. A limitation of distal procedures is that the capital fragment can only be transposed by a maximum of 50% of the metatarsal width before inviting instability, fourth/fifth intermetatarsal angle correction is therefore limited by metatarsal width at the distal metaphysis. In the 22 metatarsals involved in this study, the mean width of the metatarsal at the distal metaphysis measured on X-ray was 10.65 mm (range = 9.2–12.4 mm) and the mean length from base to distal metaphysis was 57.5 mm (range = 55.2–61.5 mm). As the capital fragment can only be transposed by 50% of the metatarsal width i.e. 10.65/2 = 5.33 mm in the ‘average metatarsal’ in this study, simple
P. Bewick, T.E. Kilmartin / The Foot 13 (2003) 190–195
195
(1) It is capable of correcting fourth/fifth intermetatarsal angles of up to 16◦ . (2) In our experience it is not associated with the complications of transfer metatarsalgia or non-union. (3) It is a stable osteotomy amenable to internal fixation, allowing early mobilization.
Fig. 7. Calculation of fourth/fifth intermetatarsal angle correction available using a distal osteotomy in the ‘Average’ fifth metatarsal.
trigonometry can be used to calculate that the maximum intermetatarsal angle correction available using a distal procedure, which in the average fifth metatarsal would be 5◦ (Fig. 7). Trepal [8], on review of the literature, found that tailor’s bunion tends to become symptomatic at a fourth/fifth intermetatarsal angle of approximately 9◦ . Based on Trepal’s findings, one of the aims of tailor’s bunion correction, therefore, should be to reduce the fourth/fifth intermetatarsal angle to below 9◦ . As distal procedures are only capable of reducing the fourth/fifth intermetatarsal angle by 5◦ . It follows, therefore, that distal procedures would be unsuitable for correcting intermetatarsal angles exceeding 13◦ in this cohort. Five patients in this study group presented with fourth/fifth intermetatarsal angles of 13◦ or greater. The intermetatarsal angle was reduced to below 9◦ in all of these patients at final review. The rotational osteotomy would therefore appear to exceed the capabilities of distal procedures in terms of IM angle reduction. Basal osteotomy may be used to correct large intermetatarsal angles. Diebold [9] reports good results using a basal chevron procedure, with the mean fourth/fifth intermetatarsal angle being reduced from 12.1 to 1.3◦ in 20 patients (22 feet). Patients were required to ambulate in a special post-operative shoe for 6 weeks to prevent weight bearing upon the forefoot. There were three cases of delayed union which resolved within 6 months. One possible criticism of this study is that X-rays were not obtained at 8 weeks post-operatively when the patients were discharged, to assess the possibility of delayed union. This study was retrospective, and it was not the policy of either of the two surgeons involved to obtain X-rays at patient discharge. Patients were advised however to contact should they have any concerns, and no patients in this study related a history consistent with symptomatic delayed union. The advantages of the rotational osteotomy appear to be three-fold:
All patients in this study were able to walk in normal footwear 2 weeks post-operatively. The reported complications of mild occasional pain in the fifth metatarso-phalangeal joint in three patients, and of retraction of the fifth toe in one patient may be due post-operative fibrosis of the joint. This may suggest that fifth metatarso-phalangeal joint range of motion exercises should be instigated post-operatively. 6. Conclusion The rotational osteotomy appears to be a successful procedure for the correction of tailor’s bunion deformity, and compares favourably with other procedures described in the literature. 75% of patients were complication free and 100% of patients stated that they were satisfied with the outcome of this procedure at an average of 27 months postoperatively.
Acknowledgements The authors would like to thank Mr. A. Wilkinson FpodA FCPodS for his help in this study.
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