Recurrence of Hallux Valgus Can Be Predicted from Immediate Postoperative Non-Weight- Bearing Radiographs

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1 1190 COPYRIGHT Ó 2017 BY THE OURNAL OF BONE AND OINT SURGERY, INCORPORATED A commentary by ákup Mijor, MD, is linke to the online version of this article at jbjs.org. Recurrence of Hallux Valgus Can Be Preicte from Immeiate Postoperative Non-Weight- Bearing Raiographs Chul Hyun Park, MD, PhD, an Woo-Chun Lee, MD, PhD Investigation performe at Inje University Seoul Paik Hospital, Seoul, Republic of Korea Backgroun: The aims of this stuy were to ientify risk factors for the recurrence of hallux valgus eformity an to clarify whether recurrence after surgery to treat hallux valgus can be preicte using raiographic parameters assesse on immeiate postoperative non-weight-bearing raiographs. Methos: A proximal chevron osteotomy combine with a istal soft-tissue proceure was performe by a single surgeon to treat moerate to severe hallux valgus eformity in 93 patients (117 feet). The feet were groupe accoring to nonrecurrence or recurrence. Changes in the hallux valgus angle, the intermetatarsal angle, an sesamoi position over time were analyze by comparing values measureuring each postoperative perio. The relative risks of recurrence as inicate by preoperative an postoperative raiographic parameters were etermine. Results: Twenty (17.1%) of the 117 feet showe hallux valgus recurrence at the time of the last follow-up. The hallux valgus angle an the intermetatarsal angle stabilize at 6 months after surgery in the nonrecurrence group. An immeiate postoperative hallux valgus angle of 8, an immeiate postoperative sesamoi position of grae 4 or greater, a preoperative metatarsus auctus angle of 23, an a preoperative hallux valgus angle of 40 were significantly associate with recurrence. Conclusions: Recurrence of hallux valgus after a proximal chevron osteotomy can be reliably preicte from immeiate postoperative non-weight-bearing raiographs. Level of Evience: Therapeutic Level III. See Instructions for Authors for a complete escription of levels of evience. Peer Review: This article was reviewe by the Eitor-in-Chief an one Deputy Eitor, an it unerwent bline review by two or more outsie experts. It was also reviewe by an expert in methoology an statistics. The Deputy Eitor reviewe each revision of the article, an it unerwent a final review by the Eitor-in-Chief prior to publication. Final corrections an clarifications occurreuring one or more exchanges between the author(s) an copyeitors. Recurrenceisacommoncomplicationaftersurgical correction of hallux valgus eformity, an reporte recurrence rates after treatment with proximal metatarsal osteotomy range from 4% to 25% 1-6. A large preoperative hallux valgus angle (HVA) 7 ;insufficient correction of the HVA 5, the intermetatarsal angle (IMA) 8,sesamoiposition 4, an the istal metatarsal articular angle (DMAA) 9 ;severe metatarsus auctus 10 ; an a roun-shape metatarsal hea 11 on postoperative raiographs have been ientifie as risk factors for the recurrence of hallux valgus eformity. However, only 1 or 2 factors were analyze in each of those stuies, an thus, a comprehensive analysis of risk factors is necessary to evaluate the relative importance of a specific riskfactor compare with another risk factor. Most stuies of the recurrence of hallux valgus have involve an analysis of raiographic parameters on weightbearing raiographs 4,5,8,9, with the exception of a stuy by Okua et al. 11, who investigate the relationship between the shape of the lateral ege of the first metatarsal hea an recurrence. If the recurrence of hallux valgus can be preicte using immeiate postoperative non-weight-bearing raiographs, evaluating intraoperative raiographs an performing aitional intraoperative proceures may be helpful to ecreasing the risk of recurrence. We believe that an immeiate postoperative Disclosure: No external funing was receive for this stuy. The Disclosure of Potential Conflicts of Interest forms are provie with the online version of the article ( Bone oint Surg Am. 2017;99:

2 1191 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG raiograph reflects the intraoperative correction at the en of skin closure because both immeiate postoperative an intraoperative raiographs are mae in a non-weight-bearing state. The aims of the current stuy were to ientify risk factors for recurrence an to clarify whether recurrence after surgery can be preicte using raiographic parameters assesse on immeiate postoperative non-weight-bearing raiographs. Materials an Methos Patient Selection The current stuy was approve by our institutional review boar. We retrospectively reviewe 105 consecutive patients (131 feet) with symptomatic, moerate to severe hallux valgus eformity (HVA of 20 or IMA of 12 ) in whom a proximal chevron osteotomy of the first metatarsal combine with a istal soft-tissue proceure was performe by a single surgeon between anuary 2008 an December The inclusion an exclusion criteria are liste in Table I. Ten patients (12 feet) were lost to follow-up, an 2 patients (2 feet) were exclue because of the absence of the meial sesamoi. A total of 93 patients (117 feet) were inclue (a follow-up rate of 89.3% of feet). All except 2 of the patients (2 feet) were female. The mean patient age was 51 years (range, 19 to 71 years), an the mean uration of follow-up was 27.5 months (range, 24 to 35 months). A closing-wege osteotomy of the proximal phalanx was performe in 70 patients (80 feet) in whom resiual hallux valgus eformity was apparent after the proximal chevron osteotomy of the first metatarsal. Hallux valgus recurrence was efine as an HVA of 20. Feetwere groupe accoring to nonrecurrence or recurrence. No ifferences in terms of age (p = 1.0), uration of follow-up (p = 0.284), an sex (p = 0.99) were observebetweenthesegroups.changesinthehva,ima,ansesamoi position over time were analyze by comparing values measure preoperatively, immeiately postoperatively, at 6 weeks an 3 an 6 months postoperatively, an at the time of the last follow-up in both groups. The preoperative an immeiate postoperative HVA, IMA, an sesamoi position; the preoperative metatarsus auctus angle; an the immeiate postoperative DMAA were compare between the 2 groups. We i not perform a comparison of the preoperative DMAA in the current stuy because the meial an lateral margins of the istal articular surface coul not be efine on many preoperative raiographs an the preoperative DMAA ha low intraobserver an interobserver reliabilities (Table II). The shape of the lateral ege of the first metatarsal hea was classifie accoring to whether the roun sign was positive an negative using the methoescribe by Okua et al. 11 an was compare between the groups. In aition, cutoff values for recurrence were etermine for each raiographic parameter, an the relative risks of recurrence as inicate by preoperative an postoperative raiographic parameters were etermine. We ranomly selecte the preoperative an postoperative orsoplantar raiographs of 51 patients on the basis of a calculation of sample size accoring to a Bonett approximation 12 to assess the intraobserver an interobserver reliabilities of raiographic measurements in this stuy. Two foot an ankle surgeons who were inepenent of the operative team an were bline to the outcome performe measurements of the raiographic parameters. Measurements were repeate 2 weeks later. The intraobserver an interobserver reliabilities of measurements of the HVA, IMA, DMAA, an metatarsus auctus angle were analyze using intraclass correlation coefficients. Kappa statistics were use for an analysis of the reliabilities of sesamoi position an the shape of the lateral ege of the first metatarsal hea. Because the postoperative HVA can be ecrease by a proximal phalangeal osteotomy, an aitional analysis was performe to etermine the effect of a proximal phalangeal osteotomy. Thus, the feet were groupe on the basis of whether or not a proximal phalangeal osteotomy was performe. Raiographic Evaluation All raiographs were mae at a single facility an accoring to the same raiographic protocol. Weight-bearing orsoplantar raiographs were mae preoperatively, at 3 an 6 months postoperatively, an at the time of the last follow-up. Non-weight-bearing orsoplantar raiographs were mae immeiately postoperatively an at 6 weeks after surgery. The raiographs were retrieve by a picture archiving an communication system (PACS) (IMPAX; Agfa HealthCare). Raiographic measurements were conucte using PACS software by 1 observer who was inepenent of the operative team an was bline to the outcome. The HVA was efine as the angle between the longituinal axis of the first metatarsal an that of the proximal phalanx. The IMA was efine as the angle between the longituinal axis of the first an that of the secon metatarsal. The longituinal axis of the first metatarsal was efine as the line connecting the center of the proximal articular surface of the first metatarsal to the center of the first metatarsal hea 13. The longituinal axis of the proximal phalanx an that of the secon metatarsal was efine as the line connecting the centers of the proximal anistal ens of the iaphysis 13. Sesamoi position was efine as the position of the meial sesamoi in relation to the longituinal axis of the first metatarsal an was grae from 1 to The DMAA was efine as the angle between a line perpenicular to the longituinal axis of the first metatarsal an a line elineating the orientation of the articular surface of the metatarsal hea 15.Themetatarsusauctus angle was measure as the position of the lesser metatarsus relative to the mifoot as escribe by Engel et al. 16. Surgical Technique A 7-cm meial incision was mae along the inferior margin of the first metatarsal. A meial capsule was vertically resecte just proximal to the base of the proximal phalanx, an excision of the meial eminence was performe at 2 mm meial to the sagittal sulcus of the metatarsal hea in a line parallel with the longituinal axis of the first metatarsal. A TABLE I Inclusion an Exclusion Criteria Inclusion Criteria* Symptomatic, moerate to severe hallux valgus (HVA of 20 or IMA of 12 ) Proximal chevron osteotomy of the 1st metatarsal by a single surgeon Primary hallux valgus surgery Age of 18 yr Min. follow-up of 24 mo Exclusion Criteria Faile previous hallux valgus surgery Absence of the meial sesamoi Inflammatory arthropathy aniabetes-relate Charcot arthropathy Hallux rigius Infection *HVA = hallux valgus angle, an IMA = intermetatarsal angle.

3 1192 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG TABLE II Intraobserver an Interobserver Reliabilities of Raiographic Measurements* Intraobserver Reliability (95% CI) Interobserver Reliability (95% CI) HVA Preop ( ) ( ) Postop ( ) ( ) IMA Preop ( ) ( ) Postop ( ) ( ) Sesamoi position Preop ( ) ( ) Postop ( ) ( ) Metatarsus auctus angle Preop ( ) ( ) DMAA Preop ( ) ( ) Postop ( ) ( ) Shape of lateral ege of 1st metatarsal hea Postop ( ) ( ) *CI = confience interval, HVA = hallux valgus angle, IMA = intermetatarsal angle, an DMAA = istal metatarsal articular angle. full-thickness orsal flap incluing skin an subcutaneous tissue was elevate to the first web space. Further issection progresse laterally, just superficial to the extensor hallucis longus tenon. The istal en of the auctor tenon aneep transverse metatarsal ligament were release. A capsular incision was then mae along the orsal margin of the lateral sesamoi. Fig. 1 Graph showing the sequential change in the hallux valgus angle over time in the nonrecurrence an recurrence groups (mean measurement an stanareviation at each time point shown; *p < 0.05 in the nonrecurrence group, an **p < 0.05 in the recurrence group).

4 1193 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG Fig. 2 Graph showing the sequential change in the intermetatarsal angle over time in the nonrecurrence an recurrence groups (mean measurement an stanareviation at each time point shown; *p < 0.05 in the nonrecurrence group, an **p < 0.05 in the recurrence group). A proximal chevron osteotomy was performe at an angle of 60. The chevron apex was place 7 mm istal to the first metatarsocuneiform joint. The correction was then accomplishe by translation an angulation at the osteotomy site. Three Kirschner wires, 1.6 mm in iameter, were then inserte proximally to istally into the metatarsal hea an burie uner the skin. Correction was checke using C-arm fluoroscopy. The meial protruing bone Fig. 3 Graph showing the sequential change in the meial sesamoi position over time in the nonrecurrence an recurrence groups (mean grae an stanar eviation at each time point shown; *p < 0.05 in the nonrecurrence group, an **p < 0.05 in the recurrence group).

5 1194 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG TABLE III Raiographic Results by Group* Group Nonrecurrence Recurrence P Value HVA ( ) Preop ± ± 9.5 <0.001 Immeiate postop. 4.9 ± ± 5.4 <0.001 IMA ( ) Preop ± ± Immeiate postop. 3.1 ± ± Sesamoi position (grae) Preop. 6.4 ± ± Immeiate postop. 2.6 ± ± Metatarsus auctus angle ( ) Preop ± ± 6.7 <0.001 DMAA ( ) Immeiate postop ± ± Roun sign (1) of 1st metatarsal hea (no. of feet [%]) Immeiate postop. 43/97 (44.3%) 8/20 (40%) *HVA = hallux valgus angle, IMA = intermetatarsal angle, an DMAA = istal metatarsal articular angle. The values are given as the mean an the stanareviation. of the proximal fragment was remove flush with the istal fragment, an this bone was place to fill the osteotomy gap. If require, a closing-wege osteotomy was performe at 5 mm istal to the proximal phalanx base. The meial capsule was repaire using absorbable sutures without tension. Postoperative Care A short leg splint was applie for 1 week postoperatively. Weight-bearing on the heel was allowe on the ay after surgery. Full weight-bearing on the first ray was not allowe until the seventh postoperative week, an Kirschner wires were removeuring the ninth postoperative week. Statistical Analysis All epenent variables were teste for normality of the ata istribution using a Kolmogorov-Smirnov test. A Mann-Whitney U test an chi-square test were use to assess the ifference in age, uration of follow-up, an sex. A Mann- Whitney U test was use for the comparison of preoperative an postoperative raiographic results between the nonrecurrence an recurrence groups. A Wilcoxon signe-rank test was use for the comparison of raiographic results at each postoperative perio. Cutoff values for raiographic parameters that allowe the preiction of hallux valgus recurrence were etermine by receiver operating characteristic (ROC) curve analysis. Cutoff values were selecte on the basis of the maximal sensitivity an specificity sum. Using etermine cutoff values, raiographic results were ichotomize. Binary logistic regression analysis was then use to etermine the risk factors for recurrence an performe using preoperative an postoperative variables separately. Os ratios (ORs) were calculate with 95% confience intervals (CIs). A chi-square test was use for an analysis of the association between the shape of the lateral ege of the first metatarsal hea an recurrence. For all tests, a p value of <0.05 was consiere significant. Power Analysis A sample-size calculation for the logistic regression was base on the guieline of Peuzzi et al. 17 :n= 10 k/p (where n is the minimum number of cases neee, k is the number of preictor variables, an p is the proportion of cases with recurrence). For our regression moel, there were 4 preictor variables an the recurrence rate was 0.171; therefore, a minimum sample size of 234 woul have been neee (see Discussion). Results The intraobserver an interobserver reliabilities of the raiographic measurements are shown in Table II. The preoperative DMAA ha the lowest reliabilities. Twenty (17.1%) of the 117 feet showe hallux valgus recurrence at the last follow-up: in 10 (50%) of the feet, the HVA was 20 to 25 ; in 4 (20%), it was 26 to 30 ; an in 6 (30%), it was 31. Changes in the HVA, the IMA, an sesamoi position in both groups are shown in Figures 1, 2, an 3. The mean preoperative HVA was significantly larger in the recurrence group (p < 0.001). The mean preoperative IMA an sesamoi position i not iffer between the nonrecurrence an recurrence groups. The mean immeiate postoperative HVA an grae of sesamoi position were significantly greater in the recurrence group (p < an p = 0.008, respectively). The mean immeiate postoperative IMA i not iffer between the 2 groups. The HVA an the IMA stabilize at 6 months after surgery in the nonrecurrence group. The mean preoperative metatarsus auctus angle an immeiate postoperative DMAA were significantly larger in the recurrence group (p < an p = 0.002, respectively). No significant ifference in the shape of the lateral ege of the first metatarsal hea was observe between the groups (Table III). Cutoff values for recurrence, which were calculate using ROC curve analysis, were 40 (area uner the curve, 0.801) for the preoperative HVA, 8 (0.795) for the immeiate

6 1195 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG TABLE IV Association Between Raiographic Parameters an Recurrence of Hallux Valgus* OR 95% CI P Value Immeiate postop. HVA of <0.001 Immeiate postop. sesamoi position of grae Preop. metatarsus auctus angle of Preop. HVA of Immeiate postop. DMAA of Immeiate postop. IMA of Immeiate postop. roun sign of 1st metatarsal hea *OR = os ratio, CI = confience interval, HVA = hallux valgus angle, DMAA = istal metatarsal articular angle, an IMA = intermetatarsal angle. Fig. 4 Graph showing the sequential change in the hallux valgus angle accoring to whether a proximal phalangeal osteotomy was performe (mean measurement an stanareviation at each time point shown; *p < 0.05 for the comparison between groups). postoperative HVA, 3 (0.507) for the immeiate postoperative IMA, grae 4 (0.682) for the immeiate postoperative sesamoi position, 17 (0.724) for the immeiate postoperative DMAA, an 23 (0.750) for the preoperative metatarsus auctus angle. The immeiate postoperative IMA, DMAA, an roun sign of the first metatarsal heai not show a significant association with hallux valgus recurrence. However, an immeiate postoperative HVA of 8, an immeiate postoperative sesamoi position of grae 4 or greater, a preoperative metatarsus auctus angle of 23, an a preoperative HVA of 40 showe a significant association with recurrence (p < to p = 0.007) (Table IV). No significant ifference with respect to the HVA at all time points after surgery was observe between the group that unerwent proximal phalangeal osteotomy an the group that i not (Fig. 4). However, the mean correction of HVA immeiately postoperatively was significantly larger in the group that unerwent proximal phalangeal osteotomy (p < 0.001). At the last follow-up, no significant ifference in the HVA was observe between the 2 groups (p = 0.918). Discussion The recurrence of hallux valgus has been variously efine 2,4,5,8,18.Verietal. 5 efine recurrence as an increase in the HVA of 10. Okuaetal. 4,8 an Coughlin an ones 2 efine recurrence as an HVA of >20. Thelowerlimitof moerate to severe hallux valgus is 20, anseveralarticles have efine recurrence after hallux valgus correction as an HVA of 20 2,4,8,11,19-21, an thus, recurrence in the current stuy was also efine as an HVA of 20.

7 1196 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG The recurrence of hallux valgus is one of the most important complications after surgery because it is closely relate to patient satisfaction 22. However, some previous stuies either i not mention the recurrence rate 23,24 or provie recurrence rates without a efinition of recurrence 3,6, Reporte recurrence rates after a proximal metatarsal osteotomy have range from 4% to 25% 1-6. In the current stuy, recurrence was foun in 20 (17.1%) of the 117 feet at the time of the last follow-up. Although a recurrence rate of 17.1%falls within the range previously reporte, it is higher than that reporte in several stuies 2,3,5,6. Patients in the current stuy ha a larger mean preoperative metatarsus auctus angle an postoperative DMAA than typically observe 7,28-30, which might explain the high rate of recurrence encountere. In aition, the mean postoperative HVA in this stuy was also comparable with that in previous reports, an 10 (50%) of all feet with recurrence ha an HVA of 20 to 25. The known risk factors for hallux valgus recurrence are a large preoperative HVA 7 ;insufficient correction of the HVA 5,the IMA 8, sesamoi position 4,antheDMAA 9 ; severe metatarsus auctus 10, an a roun-shape metatarsal hea 11. Our analysis showe that insufficient correction of the HVA an sesamoi position as assesse immeiately postoperatively, severe preoperative metatarsus auctus, an severe hallux valgus eformity as assesse by preoperative HVA are risk factors for recurrence. Hallux valgus with severe metatarsus auctus is ifficult to treat. Therefore, surgeons shoul explain the risk of recurrence when counseling patients with severe metatarsus auctus prior to surgery to correct hallux valgus eformity. Of the risk factors examine, an immeiate postoperative HVA of 8 ha the strongest association with recurrence (an OR of 28 times that of feet with an immeiate postoperative HVA of <8 ). The IMA was sufficiently correcte to an average of 3.1 immeiately postoperatively in both the nonrecurrence an recurrence groups. We think that this is the reason why insufficient correction of the IMA was not foun to be a risk factor for recurrence in this stuy. In aition, a roun-shape first metatarsal hea was also not foun to be a risk factor. In fact, 12 (18.2%) of the 66 feet with a negative roun sign on the immeiate postoperative raiograph showe recurrence at the last follow-up. Although the DMAA was also previously ientifie as a risk factor for recurrence 9, in the logistic regression analysis in the current stuy, the immeiate postoperative DMAA was not significantly associate with recurrence. However, this parameter was significantly larger in the recurrence group than in the nonrecurrence group. Therefore, we believe that in a future stuy with a larger number of cases, a large DMAA might be emonstrate to be a risk factor for recurrence. The metho of etermining the axis of the first metatarsal by bisecting the shaft of the metatarsal is wiely use to assess hallux valgus eformity 14,31. Some authors reporte that this metho showe high reliability of measurement 31. However, Schneier et al. 32 reporte that this metho showe high preoperative reliability but low postoperative reliability. Shima et al. 13 recommene the metho of etermining the axis of the first metatarsal by connecting the centers of the first metatarsal hea an the proximal articular surface because that ha the highest preoperative an postoperative reliabilities. Therefore, we use the latter metho in the present stuy. This stuy emonstrates that recurrence can be preicte from non-weight-bearing raiographs mae immeiately postoperatively. We believe that the results from the analysis of immeiate postoperative raiographs can be use to suggest intraoperative guielines for satisfactory correction of raiographic parameters because both intraoperative an immeiate postoperative raiographs are mae in a non-weight-bearing state. Therefore, we suggest that further correction shoul be performe if an HVA of 8 or sesamoi position of grae 4 or greater is observe on intraoperative raiographs. One limitation of this stuy was that a closing-wege osteotomy was performe at the base of the proximal phalanx in conjunction with a proximal chevron osteotomy in 80 of the 117 feet. Although a proximal phalangeal osteotomy alone is known to be ineffective in the prevention of hallux valgus recurrence 33-35, we know of no previous stuies of the effect when proximal phalangeal osteotomy is performe in conjunction with metatarsal osteotomy. In this stuy, the HVA showe a tenency to increase over time in patients who unerwent proximal phalangeal osteotomy, although the mean correction of HVA was significantly larger after surgery in patients who unerwent proximal phalangeal osteotomy (Fig. 4). Thus, we think that proximal phalangeal osteotomy might not have an effect on reucing the recurrence of hallux valgus. However, a prospective case-controlle trial may be neee to assess the effect of a proximal phalangeal osteotomy on the recurrence of hallux valgus. The retrospective nature of this stuy an the relatively small sample size were also limitations of this stuy. A power analysis of the logistic regression reveale that a minimum sample size of 234 woul have been require. Because this stuy i not have a large enough sample size, we performe logistic regression using preoperative an postoperative variables separately to enhance statistical power. Therefore, we think that a ranomize controlle trial with a large sample is neee. Another limitation was that immeiate postoperative raiographs were use instea of intraoperative raiographs to assess the state of intraoperative correction at the en of surgery. Although both immeiate postoperative raiographs an intraoperative raiographs are mae in a non-weight-bearing state, the surgeon can make raiographs intraoperatively that are similar to those of a weight-bearing state because patients are uner anesthesia. In aition, there is a possibility that a raiograph mae after ressing the woun an applying a splint may not be the same as the intraoperative raiograph. However, we i not attempt to sprea the big toe from the secon toe using thick ressing material. Therefore, we believe that the immeiate postoperative raiograph reflects the state of intraoperative correction. In summary, risk factors for hallux valgus recurrence were insufficient correction of the HVA an sesamoi position as assesse immeiately postoperatively, severe preoperative metatarsus auctus, an severe hallux valgus eformity as assesse by preoperative HVA. Using an immeiate postoperative HVA cutoff of 8, feet with an HVA of 8 ha an OR for recurrence of 28 times that of feet with an HVA of <8. Accoringly, we

8 1197 T HE OURNAL OF B ONE &OINT SURGERY BS. ORG conclue that recurrence after proximal chevron osteotomy for hallux valgus can be preicte from immeiate postoperative non-weight-bearing raiographs. n Chul Hyun Park, MD, PhD 1 Woo-Chun Lee, MD, PhD 2 1 Department of Orthopeic Surgery, Yeungnam University Meical Center, Daegu, Republic of Korea 2 Seoul Foot an Ankle Center, Inje University Seoul Paik Hospital, Seoul, Republic of Korea aress for C.H. Park: chpark77@naver.com aress for W.-C. Lee: leewoochun@gmail.com ORCID id for W.-C. Lee: References 1. Tanaka Y, Takakura Y, Kumai T, Sugimoto K, Taniguchi A, Hattori K. Proximal spherical metatarsal osteotomy for the foot with severe hallux valgus. Foot Ankle Int Oct;29(10): Epub 2008 Oct Coughlin M, ones CP. Hallux valgus an first ray mobility. A prospective stuy. Bone oint Surg Am Sep;89(9): Mann RA, Ruicel S, Graves SC. Repair of hallux valgus with a istal soft-tissue proceure an proximal metatarsal osteotomy. A long-term follow-up. 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