Long Oblique Distal Osteotomy of the Fifth Metatarsal for Correction of Tailor s Bunion: A Retrospective Review

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1 Long Oblique Distal Osteotomy of the Fifth Metatarsal for Correction of Tailor s Bunion: A Retrospective Review Barry P. London, DPM, 1 Stephen F. Stern, DPM, 2 Mark A. Quist, DPM, 3 Robert K. Lee, DPM, 3 and Edison K. Picklesimer, DPM 4 A long-term retrospective review of a long oblique distal osteotomy of the fifth metatarsal for correction of a tailor s bunion deformity is presented. The technique, results, and follow-up of this procedure are described. The long oblique distal osteotomy was performed on 25 feet on 16 patients. Follow-up ranged from 11 to 110 months with an average of 64.4 months. The average preoperative intermetatarsal 4-5 angle and lateral deviation angle improved from and 4.24, respectively, to 5.52 and 4.24 postoperatively, respectively. A modified scoring scale for lesser metatarsal procedures was used, showing an average postoperative score of 94 out of 100 possible points. Subjectively, 96% (24 of 25) of feet that underwent surgery were rated as excellent or good. Complications included one patient with paresthesias, one soft-tissue infection, and 2 patients had irritation from screws. The authors conclude that the long oblique distal osteotomy is a viable alternative in the correction of tailor s bunion deformity. (The Journal of Foot & Ankle Surgery 42(1):36 42, 2003) Key words: bunionette, fifth metatarsal, intermetatarsal 4-5 angle, lateral deviation angle, osteotomy tailor s bunion The exact cause of tailor s bunion deformity or bunionette is unknown. Various causes have been proposed, and have been subdivided into structural or mechanical origins. Davies was the first to address the etiology of tailor s bunion, and attributed it to incomplete development of the transverse metatarsal ligament, resulting in splaying of the fifth metatarsal (1). DuVries described 3 mechanisms, acting alone or in combination, that contribute to the formation of tailor s bunions: 1) hypertrophy of the soft tissue overlying the fifth metatarsophalangeal joint (MTPJ), 2) a congenitally wide or dumbbell-shaped fifth metatarsal head, and/or 3) lateral deviation of the fifth metatarsal head (2). Other investigators also have advocated these same causes (3 6). Root et al. (4) emphasized the significance of biomechanics in the development of the deformity. They suggested that abnormal pronation during gait results in hypermobility of the fifth ray and subsequent abduction, eversion, and dorsiflexion of the metatarsal leading to a dorsilateral bunion. From the From Northern Virginia Podiatric Residency Program/Inova Fairfax Hospital, Vienna, VA. Address correspondence to: Stephen F. Stern, DPM, Program Director, 301 Maple Ave West, Vienna, VA vpod@erols.com. 1 Attending Surgeon (retired). 2 Residency Director. 3 Former Chief Resident. 4 Current Chief Resident. Copyright 2003 by the American College of Foot and Ankle Surgeons /03/ $30.00/0 doi: /jfas Nestor et al. (7) showed that feet with symptomatic tailor bunions had significantly increased intermetatarsal 4-5 angles when compared with a control group. Numerous surgical procedures have been described for the tailor s bunion deformity that has been recalcitrant to conservative treatment. Lateral condylar resection may be indicated for the mild, symptomatic deformity but may have limited use with greater deformity and/or presence of intractable plantar keratoses (8). Metatarsal head resection and implant arthroplasty can result in joint instability, a floppy fifth toe, and/or transfer metatarsalgia (3, 9, 10). Metatarsal osteotomies allow for bony realignment and have been described at the proximal, diaphyseal, and metaphyseal levels. Free-floating osteotomies that seek their own level have been fraught with complication and have fallen into disfavor (11 14). Osteotomy and internal fixation can be difficult technically owing to the narrowness of the fifth metatarsal. We retrospectively review the long-term results of the long oblique distal osteotomy (LODO) of the fifth metatarsal in the correction of tailor s bunion deformity. To our knowledge, this osteotomy has not yet been described for the correction of tailor s bunion deformity. Materials and Methods All patients who had the index procedure were eligible for the study. They were all from the private practice of the senior 36 THE JOURNAL OF FOOT & ANKLE SURGERY

2 TABLE 1 Modified 100-point American Orthopedic Foot and Ankle Society Scale for lesser metatarsophalangeal procedures (12) Categories Survey of 16 Patients: LODO Procedure Performed on 25 Feet Points per Category No. Feet per Category Pain 40 points None Mild, occasional 30 3 Moderate, daily 20 1 Severe, almost always 0 0 Function 45 points Activity limitations No limitations No limitation of daily activities, limitation of recreational activities 7 2 Limited daily and recreational activities 4 0 Severe limitation of daily and recreational activities 0 0 Footwear requirements Fashionable, conventional shoes Comfort footwear 5 7 Modified shoes or brace 0 0 Fifth MTPJ range of motion v contralateral side Normal or mild restriction 5 23 Moderate restriction (stiffness) 3 2 Severe restriction 0 0 Fifth MTPJ Stability Stable, unable to sublux or dislocate 5 23 Unstable, able to sublux or dislocate 0 2 Presence of callus under fifth metatarsal head No callus or asymptomatic callus 5 22 Symptomatic callus 0 3 Presence of transfer lesion to fourth metatarsal head No callus or asymptomatic callus 5 25 Symptomatic callus 0 0 Alignment 15 points Good, fifth digit well aligned Fair, some degree of malalignment without symptoms 8 2 Poor, severe malalignment with symptoms 0 0 NOTE. Grading: excellent, points; good, points; satisfactory, points; poor, 70 points. Average score: (range, ). See Table 2 for individual patient scores. author (B.P.L.). Inclusion into the study was based on the following criteria: 1) failure to achieve relief of symptoms from conservative care that included orthotics, padding, and shoe gear modifications; 2) no other coexisting pathology at time of surgery; and 3) no history of prior surgical treatment to the affected area. In all cases, no other procedures were performed concomitantly with the LODO. Based on these criteria, an initial pool of 19 eligible cases was reviewed. Three patients were lost to follow-up, comprising a final study group of 16 patients (25 procedures). Medical charts and radiographs were reviewed for all patients. A modified version of the 100-point American Orthopedic Foot and Ankle Society Scale for Lesser Metatarsophalangeal Procedures (15) (Table 1) was used to assess subjective and functional outcomes of the procedure. This assessment included presence of pain, activity restrictions, footwear restrictions, joint range of motion and stability, and the presence of a callus under the fifth metatarsal head or a fourth metatarsal transfer lesion. This assessment, which was performed via telephone interview in all 16 patients by the same person (M.A.Q.), evaluated only the postoperative state. Follow-up ranged between 11 to 110 months (average, 64.4 mo). The scale was modified to exclude criteria from the original scale that did not apply to tailor s bunion pathology as well as to facilitate its use with a telephone interview. Assessment of interphalangeal joint range of motion, for example, was replaced with presence of transfer lesion to the fourth MTPJ. Point values were distributed for assessment of pain (40 points), function (45 points), and alignment (15 points). The results were graded as excellent ( points), good (80 89 points), satisfactory (70 79 points), and poor ( 70 points). Additionally, each patient was asked to subjectively rate their surgery as excellent, good, fair, or poor, and to assess whether or not they would have this surgery again. VOLUME 42, NUMBER 1, JANUARY/FEBRUARY

3 FIGURE 2 LODO fixated with two 2.0-mm cortical screws. FIGURE 1 Diagram depicting LODO of fifth metatarsal directed from dorsal-distal to plantar proximal after resection of the prominent lateral condyle. The capital fragment is translocated medially to correct for the increased 4-5 IMA. Preoperative anteroposterior and lateral radiographs of each foot were examined and compared with the radiographs taken 2 6 weeks postoperatively. The 4-5 intermetatarsal angles (4-5 IMA) and fifth metatarsal lateral deviation angles (LDA) were measured as described by Fallat and Bucholz (16). FIGURE 3 A Kirschner wire being used as an axis guide to direct osteotomy. Angulation of the axis guide determines the amount of dorsal or plantar displacement obtained with translocation of the capital fragment. Surgical Procedure A longitudinal incision is placed just lateral to the extensor tendon over the fifth ray. On deeper dissection, the periosteal and capsular tissues overlying the fifth MTPJ and distal aspect of the fifth metatarsal are incised and reflected. The dorsolateral or lateral prominence on the fifth metatarsal head is resected with a power saw with the cut flush with the metatarsal shaft. The osteotomy is made on the distal half of the fifth metatarsal from dorsal-distal just proximal to the articular cartilage. It courses plantar-proximal to a point one third to one half of the length of the metatarsal. Care is taken to preserve a plantar cortical hinge about which the capital fragment is rotated medially to the desired position (Fig. 1). Temporary fixation may be achieved with Kirschner wires or a bone clamp, followed by the implantation of two 2.0-mm cortical screws (Fig. 2). Any remaining overhanging edges or bony prominences are then rasped smooth, and the wound is then closed in typical fashion. Slight angulation of the osteotomy in the frontal plane offers the ability to gain multiplanar correction. Insertion of a Kirschner wire at the location of the plantar hinge to act as an axis guide may facilitate this angulation (Fig. 3). The presence of an intractable plantar keratosis with an associated plantar-flexed fifth metatarsal can be addressed by angulation of the osteotomy from plantar-lateral to dorsomedial. This will result in dorsiflexion of the capital fragment as it is rotated medially. Further dorsiflexory correction can be obtained by performing the osteotomy with 2 saw blades, which removes more bone and further elevates the capital fragment when the osteotomy is fixated. Postoperatively the patients were instructed to partial weight-bear on the heel in a surgical shoe with crutches for 4 weeks. Then patients were returned gradually into their regular shoe gear as tolerated. Results A total of 25 LODO procedures were performed on 16 patients: 14 on right foot, 11 on left foot, 9 cases were bilateral (Table 2). Follow-up for this study was performed by phone for all 16 patients at an average of 64.4 months postoperatively (range, mo). Based on the modified 100-point American Orthopedic Foot and Ankle Society Scale for Lesser Metatarsophalangeal Procedures (15), the mean total score of all patients was (range, ). According to this scale, 19 feet (76%) were rated as excellent, 5 feet (20%) as good, and 1 foot as poor. Subjectively, in 72% (18 feet) of the procedures, the patients rated the outcome of the surgery as excellent. Twenty-four percent (6 feet) were rated as good, and 4% (1 38 THE JOURNAL OF FOOT & ANKLE SURGERY

4 FIGURE 4 Preoperative anteroposterior radiograph depicting tailor s bunion deformity. foot) was rated as poor. In the case of the single poor result, the patient complained of burning pain postoperatively caused by nerve entrapment. All patients except the one with the poor result stated that they would undergo the procedure again. Twenty-one of the 25 feet (84%) were without pain postoperatively, whereas 3 (12%) had mild, occasional pain and 1 experienced moderate daily pain. Twentythree of 25 feet (92%) had no limitations of daily activity. Two feet were noted to have limited activity related to recreational activities. Seven feet (28%) still required comfortable shoes and could not tolerate fashionable conventional shoes. No patients required modified shoes or braces. Two feet (8%) showed some joint stiffness to the fifth MTPJ. All other feet had normal or mild restriction of motion. Two feet (8%) were noted to have unstable or dislocatable fifth MTPJs. Three feet (12%) continued to have a symptomatic callus underneath the fifth metatarsal head. In none of these cases was the callus more symptomatic than before surgery. Furthermore, no FIGURE 5 Postoperative anteroposterior radiograph showing correction obtained with LODO procedure. patients claimed to have a transfer callus under the fourth metatarsal head. Alignment assessment showed 2 feet (8%) to have fair or some degree of malalignment to the fifth toe. Both feet were not symptomatic. All other feet were in normal alignment (Table 1). Complications occurred in 4 feet (16%): superficial infection controlled with oral antibiotics (one foot), irritation from prominent screws (2 feet), and nerve entrapment (1 foot). The final functional score and outcome of these patients were 80 (good), 100 (excellent), 88 (good), and 57 (poor), respectively. No case of delayed or nonunion, avascular necrosis, degenerative arthritis, or transfer metatarsalgia was encountered. Radiographic analysis showed a mean preoperative 4-5 IMA of (range, 7 to 17 ) (Fig. 4), decreasing to a mean of 5.52 (range, 3 to 7 ) at latest postoperative radiograph (Figs. 5 and 6). Mean change in IMA was The LDA decreased from a mean value of 4.24 (range, 1 to 8 ) to a mean of 4.24 (range, 0 to 8 ) postoperatively. Mean change in LDA was 4.24 (Table 2). VOLUME 42, NUMBER 1, JANUARY/FEBRUARY

5 FIGURE 6 Postoperative lateral radiograph showing osteotomy and screw fixation. Discussion The LODO procedure was performed for the treatment of tailor s bunions that were recalcitrant to conservative forms of care. Approximately 96% of the feet (24 of 25) were rated as good or excellent. There was no incidence of transfer lesions to the fourth metatarsal. Although 3 feet showed symptomatic callus beneath the fifth metatarsal, in none of these cases was the procedure performed using the 2 saw-blade technique. This technique often is useful when additional dorsiflexion of the capital fragment is desired. This study has several weaknesses. Because of the retrospective nature, the lack of preoperative assessment makes it difficult to interpret the degree of subjective improvement from the preoperative state. Without the authors having had the opportunity to perform a preoperative subjective evaluation of these patients, there is a resultant total reliance on patients recollections regarding their initial deformities and associated symptoms. This could potentially lead to a bias, either positive or negative, from the patient s perspective as to the overall improvement and satisfaction of the procedure. Telephone interviews with the patients, in lieu of in-person interviews and hands-on clinical evaluations, could likewise have resulted in an overreliance on patients perceptions. In addition, radiographs were taken between 2 6 weeks postoperatively, rather than serially and at fixed standardized times during the postoperative period. The composite data obtained, therefore, represented radiographic analysis of patients at various stages of healing, weight bearing, and shoe wearing. These variables potentially could have resulted in skewed data. Additionally, the lack of long-term radiographic follow-up fails to confirm that the radiographic results noted in the immediate postoperative period were maintained over the long term. Regardless, from a subjective standpoint, 15 of the 16 patients indicated they were sufficiently satisfied with the result that they would undergo the procedure again. From an objective radiographic standpoint, increased 4-5 IMAs and LDAs have been correlated with the presence of tailor s bunion deformity (16). In our series, values were decreased postoperatively by 5.3 and 8.5, respectively (Table 2). Fallat and Bucholz found the average normal 4-5 IMA and LDA to be 6.5 and 2.6, respectively (16). Leach and Igou considered a tailor s bunion deformity with a 4-5 IMA greater than 9 to be appropriate for correction with an osteotomy rather than a condylectomy (3). In this study, the average preoperative 4-5 IMA and LDA values were and 4.24, respectively, and the average postoperative values were 5.52 and 4.24, respectively. Basal osteotomies may offer the greatest potential for angular correction, but also come with increased risk for cortical hinge fracture, metatarsal elevation or shortening, and decreased inherent stability owing to the lever arm mechanics. The increased possibility also exists for disrupting the nutrient artery, which can result in delayed union or nonunion (17). Distal osteotomies can be difficult technically owing to the narrowness of the fifth metatarsal neck. This also limits the amount of medial transposition of the capital fragment, and hence the overall correction. Additionally, once medial transposition of the capital fragment is performed, most 40 THE JOURNAL OF FOOT & ANKLE SURGERY

6 TABLE 2 Radiographic data and subjective ratings Pt # Age (y)/sex Foot No./ Affected Limb Follow-Up (mon) Preoperative 4 5 IMA Postoperative 4 5 IMA Change in 4 5 IMA Preoperative LDA Postoperative LDA Change in LDA Total Score a Subjective Rating F 1. R Good 2. L Excellent F 3. R Excellent F 4. L Good M 5. R Excellent F 6. R Excellent 7. L Excellent F 8. R Excellent 9. L Good F 10. L Excellent F 11. R Excellent 12. L Good F 13. R Excellent 14. L Excellent F 15. R Excellent 16. L Excellent F 17. R Good 18. L Excellent F 19. R Excellent F 20. R Poor F 21. R Excellent 22. L Excellent F 23. R Excellent 24. L Excellent F 25. R Good Average a Total Score based on modified 100-point American Orthopedic Foot and Ankle Society Scale for lesser metatarsophalangeal procedures (12). Postoperative radiographs were taken in the time interval of 2 6 weeks post-lodo procedure. F, female; R, right; L, left; M, male. distal osteotomies preserve very little bony apposition of the bone ends, often making adequate fixation difficult. The LODO is a relatively easy procedure to perform because it requires only a single plane osteotomy. Additionally, its design allows for multiplanar correction with alteration of the axis of the osteotomy. The increased length of the osteotomy affords greater bone-to-bone contact, as well as allowing for greater angular rotation. Additionally, it facilitates the use of 2 screw fixations for stability. A similar osteotomy (the oblique shaft osteotomy) was described by Coughlin, but in reverse fashion such that the single osteotomy was made from dorsal-proximal to plantar-distal (12). Although the length of the osteotomy also affords it improved bony apposition, increased angular correction, and ease of fixation, its design is inherently less stable from a dynamic standpoint in that weight-bearing forces act to distract the osteotomy, whereas with the LODO they help to compress the osteotomy. Summary The LODO of the fifth metatarsal is a technically noncomplex, yet reliable and versatile, procedure in the correction of tailor s bunion deformity, with or without associated plantar keratosis. The design of the osteotomy allows for excellent bony apposition, uncomplicated fixation, controlled medial realignment of the capital fragment, and multiplanar correction. Favorable outcomes have been shown in this series of patients. References 1. Davies, H. Metatarsus quintus valgus. Br. Med. J. 1: , DuVries, H. L. Surgery of the Foot, 3rd ed., p. 236, C.V. Mosby, St Louis, Leach, R. E., Igou, R. Metatarsal osteotomy for bunionette deformity. Clin. Orthop. 100: , Root, M. L., Orien, W. P., Weed, J. H. Normal and Abnormal Function of the Foot, 1st ed., pp , Clinical Biomechanics Corporation, Los Angeles, Sgarlato, T. E. Compendium of Podiatric Biomechanics, p. 381, California College of Podiatric Medicine, San Francisco, Yancey, H. A. Congenital lateral bowing of the fifth metatarsal. Clin. Orthop. 62: , Nestor, B. J., Kitaoka, H. B., Strup, D., et al. Radiologic anatomy of the painful bunionette. Foot Ankle 11:6 11, VOLUME 42, NUMBER 1, JANUARY/FEBRUARY

7 8. Kitaoka, H. B., Holiday, A. D. Lateral condylar resection for bunionette. Clin. Orthop. 278: , Dorris, M., Mandel. L. Fifth metatarsal head resection for correction of tailor s bunions and sub-fifth metatarsal head keratoma: a retrospective analysis. J. Foot Surg. 30: , Kitaoka, H. B., Holiday, A. D. Metatarsal head resection for bunionette: long-term follow-up. Foot Ankle 1: , Catanzariti, A. R., Friedman, C., Distazio, J. Oblique osteotomy of the fifth metatarsal: a five year review. J. Foot Surg. 27: , Coughlin, M. L. Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with soft tissue repair. Foot Ankle 11: , Sponsel, K. H. Bunionette correction by metatarsal osteotomy. Orthop. Clin. North Am. 7: , Wu, K. Surgery of the metatarsal region. Surgery of the Foot, pp , Lea and Febiger, Philadelphia, Fallat, L. M., Bucholz, J. L. An analysis of the tailor s bunion by radiographic and anatomic display. J. Am. Podiatr. Med. Assoc. 70: , Kitaoka, H. B., Alexander, I. J., Adelaar, R. S., Nunley, J. A., Myerson, M. S., Sanders, M. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int. 18: , Smith, J. W., Arnoczky, S. P., Hersh, A. The intraosseous blood supply of the fifth metatarsal: implications for proximal fracture healing. Foot Ankle 13: , THE JOURNAL OF FOOT & ANKLE SURGERY