If you don't remember your password, you can reset it by entering your email address and clicking the Reset Password button. You will then receive an email that contains a secure link for resetting your password
If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password
Comparison of short-term outcomes after distal metatarsal telescoping osteotomy and scarf osteotomy for hallux valgus in patients with rheumatoid arthritis
Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, JapanDepartment of Rheumatology, Tokyo Metropolitan Bokutoh Hospital, 4-23-15 Koutoubashi, Sumida-ku, Tokyo, 130-8575, Japan
Corresponding author at: Takumi Matsumoto, MD, PhD, Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
Department of Rheumatology, Tokyo Metropolitan Bokutoh Hospital, 4-23-15 Koutoubashi, Sumida-ku, Tokyo, 130-8575, JapanUchida clinic, 3-6-1 Kinshi, Sumida-ku, Tokyo, 130-0013, Japan
Department of Rheumatology, Tokyo Metropolitan Bokutoh Hospital, 4-23-15 Koutoubashi, Sumida-ku, Tokyo, 130-8575, JapanDepartment of Rheumatic Surgery, Tokyo Metropolitan Tama Medical Center, 2-28-29 Musashidai, Fuchu-shi, Tokyo 183-8524, Japan
To compare the clinical and radiographic outcomes of distal metatarsal telescoping osteotomy (DMTO) and scarf osteotomy for hallux valgus (HV) in patients with rheumatoid arthritis (RA).
Methods
Overall, 21 feet in 19 patients treated with DMTO and 26 feet in 26 patients treated with scarf osteotomy were retrospectively compared with significantly longer follow-up periods in the former procedure (51.0 months vs. 28.0 months, P < 0.0001). Radiographic measurements of HV-related parameters and the clinical outcomes which were compared using the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal joint score (AOFAS score) were obtained preoperatively and at the latest follow-up. A postoperative comparison of the patient-reported outcome measures was performed using the Self-Administered Foot Evaluation Questionnaire (SAFE-Q).
Results
Both the DMTO and scarf procedures improved the AOFAS score and HV-related parameters. The improvement in the AOFAS score and corrective amount of radiographic parameters showed no significant differences between the two groups. The pain and pain-related subscales of the SAFE-Q were significantly better in the DMTO group (86.7 vs. 70.0, P = 0.0009). The operative time for all toes was significantly shorter in the DMTO group (176.0 min vs. 210.0 min, P = 0.0002). No significant differences were observed in the incidence of post-operative complications.
Conclusion
Both DMTO and scarf osteotomy demonstrated comparable outcomes for mild-to-severe HV deformities in patients with RA. The DMTO may be considered as an alternative surgical method for HV deformity in patients with RA with the advantages of being an easy technique and having a shorter operative time.
Rheumatoid arthritis (RA) is a chronic autoimmune disease affecting multiple joints. Recently, the management of RA has become refined owing to the development of powerful anti-rheumatic drugs and establishment of treatment strategies. While the number of surgeries for the large joints, especially the hip or knee, have decreased by the improved management of RA disease activity, demand for the surgery of the small joints in hand and foot have not decreased.
Trends in treatment, outcomes, and incidence of orthopedic surgery in patients with rheumatoid arthritis: an observational cohort study using the Japanese National Database of Rheumatic Diseases.
Rheumatic forefoot deformities, which are characterized by hallux valgus (HV), subluxation or dislocation at the metatarsophalangeal (MTP) joints, and hammer toe deformity of the lesser toes are directly related to the pain during walking and affect the activities of daily living and quality of life of the patients significantly; therefore, early and appropriate therapeutic interventions are necessary. Historically, the main surgical treatment for forefoot deformities in patients with RA was resection arthroplasty. However, in recent years, MTP joint-preserving procedures have become mainstream owing to the tight control of disease activity by successful medications.
Several types of osteotomies have been reported as surgical treatments for HV, and the surgical technique is generally selected according to the surgeon's preference and severity of HV deformity. The severity of HV deformity is generally classified into four stages according to the HV angle; < 20º, normal; 20-29º, mild; 30-39º, moderate; and ≧ 40º, severe.
Distal metatarsal osteotomy, such as Mitchell or Chevron osteotomy, is generally selected for deformities up to moderate HV. On the other hand, deformities from moderate to severe HV are usually treated by a mid-shaft osteotomy, such as scarf osteotomy or proximal metatarsal osteotomy, such as Mann osteotomy or Lapidus arthrodesis. Similarly, several kinds of joint-preserving procedures using osteotomy have been reported for HV deformities in patients with RA.
Prior to April 2015, we had been performing distal metatarsal telescoping osteotomy (DMTO) for mild-to-severe HV in patients with RA. After May 2015, we performed scarf osteotomy. In the present study, we hypothesized the superiority of scarf procedure to DMTO in correction of severe HV and compared the short-term postoperative results of DMTO and scarf osteotomy procedures in patients with RA.
Patients and methods
Study design
The present study enrolled patients with RA who underwent joint-preserving surgery on all five toes as the primary procedure for forefoot deformities between September 2013 and August 2018. We adopted the DMTO until April 2015 and the scarf since May 2015 for mild to severe HV and the Lapidus procedure for cases with HVA consistently exceeding 65°. Excluding the cases treated with the Lapidus procedure, 25 feet in 22 patients and 35 feet in 35 patients were operated on using the DMTO and scarf procedures, respectively. The postoperative clinical outcomes and radiographs of these subjects were surveyed when the patients visited our hospital regularly for RA between March 2018 and September 2018. Notably, four feet in three patients with DMTO and nine feet in nine patients with scarf were lost to follow-up. Finally, 21 feet of 19 patients with DMTO and 26 feet of 26 patients with scarves were enrolled. Preoperative patient information, including age, body mass index (BMI), medical history of diabetes mellitus and chronic kidney disease, current smoking habit, duration of RA disease, serum matrix metalloproteinase-3 (MMP-3) level, Disease Activity Score-28 for RA with CRP (DAS28-CRP), and medications for RA were obtained from the medical charts. Information regarding additional procedures for the hallux (Akin osteotomy, 1st IP joint arthrodesis) and operative time was obtained from the operative records. The postoperative complications were investigated using the medical records.
DMTO
A medial skin incision, 7 cm in length, was made along the bony axis over the first MTP joint. The capsule was incised longitudinally along the skin incision. A lateral capsular release at the MTP joint level was performed trans-articularily in all the cases. When the manual reduction of the hallux could not be into at least a 20° varus position, the suspensory ligament and adductor tendon were additionally released. The DMTO consists of double osteotomies at the first metatarsal shaft with a trapezoid bone piece resection between the double osteotomies (Fig. 1). The first osteotomy was set vertically to the axis of the metatarsal and 15 mm proximal to the metatarsal head. Subsequently, the second osteotomy was set proximal to the first osteotomy vertically or slightly in varus to the axis of the metatarsal to correct the articular surface of the first metatarsal head tilted valgus. The bone between the two osteotomies was resected, and the width of the resected bone was determined based on the shortening length required to match the position of the second metatarsal head. The distal bone fragment was translated proximally in order to close the gap and laterally to correct HV. The osteotomy site was fixed using a 1.5-mm Kirschner wire (K-wire) inserted from the toe tip. After the joint capsule was repaired, the plantarly displaced abductor hallucis tendon was pulled to the medial side of the first MTP joint and sutured to the capsular surface.
Fig. 1Representative anteroposterior foot radiographs of cases having the distal metatarsal telescoping osteotomy (DMTO). (A) Preoperative. Black arrows indicate the double osteotomy lines in the DMTO. (B) At postoperative one week. Each toe was temporarily fixed with a Kirschner wire. (C) Five years after surgery.
A medial skin and capsule incision was placed similar to the DMTO, except for the longer length proximally than the DMTO. After a Z-shaped osteotomy, the distal fragment was displaced laterally and fixed with two headless compression screws.
The first metatarsal was shortened before fixation by cutting both the proximal and distal apex when required to match the length of the lesser toes. Lateral release of the first MTP joint and relocation of the abductor hallucis tendon were performed in the same manner as the DMTO.
Surgical procedure for lesser toes and postoperative course
In all the cases, the distal metatarsal shortening oblique osteotomy of the lesser toes was performed according to the method described by Hanyu et al.
The patients were allowed to walk in heel gait immediately after surgery. Full weight bearing without toe push-off was allowed three weeks after surgery. Normal ambulation with the toe push-off phase was allowed three months after surgery.
Clinical and radiographic assessments
The clinical outcome was measured using American orthopaedic foot and ankle society Hallux MTP-IP score (AOFAS score) preoperatively and postoperatively, using a self-administered foot evaluation questionnaire (SAFE-Q) postoperatively only. SAFE-Q is a patient-reported outcome measure which was developed and validated by the Japanese Society for Surgery of the Foot.
As the radiographic outcomes, we evaluated the HV angle, intermetatarsal angle between the first and the second metatarsals (M1M2 angle), the differences of the length between the first and the second metatarsal (1-2 difference), and the positions of the medial sesamoid using Hardy grade, with a preoperative and postoperative anteroposterior view of weight-bearing radiographs. The 1-2 difference was measured using Hardy–Clapham's method and expressed as absolute values.
Delayed wound healing was defined as a case in which wound healing was not achieved after three weeks postoperatively. Surgical site infection was defined according to the CDC criteria.
Recurrence of HV and postoperative hallux varus were defined as an HV angle of 20° or more and less than 0° on postoperative radiographs, respectively. Avascular necrosis (AVN) of the metatarsal head of the hallux was defined as the finding of destruction of the head surface on postoperative radiographs, which differ from erosion or arthropathic changes. Nonunion was defined as no bony fusion at one year after surgery. The clinical and radiographic outcomes were compared between the DMTO and scarf groups. Furthermore, we focused on patients with preoperative severe HV with an HV angle of more than 40° and compared the outcomes similarly between the two groups.
Statistical analysis
Continuous variables were represented as medians and interquartile ranges. Categorical variables were expressed as numbers and percentages. Continuous variables between the DMTO and scarf groups were compared using the Mann–Whitney U test. Continuous variables were compared between the preoperative and postoperative conditions in each group using the Wilcoxon test. The chi-square test was used to compare the categorical variables. For each statistical analysis, a P-value less than 0.05 was considered as statistically significant. All statistical analyses were performed using PRISM version 9.3.1 (GraphPad Software, San Diego, California, USA).
This study was performed with the approval of the relevant ethics committee at Tokyo Metropolitan Bokutoh Hospital (approval No. 02-122).
Results
Preoperative characteristics of patients
Table 1 shows the patients’ preoperative characteristics. There were no significant differences between the DMTO and scarf groups in terms of age, BMI, medical history, current smoking habit, disease duration, MMP-3, DAS-CRP, and medications. The postoperative observation period was significantly longer in the DMTO group (51.0 [42.0–54.0] months) than in the scarf group (51.0 [42.0–54.0] months vs 28.0 [20.3–36.0] months, P < 0.0001). The comparison of preoperative radiographic parameters and AOFAS scores showed no significant differences between the two groups. As additional procedures for the hallux, Akin osteotomy was performed in two cases in the DMTO group and five cases in the scarf group, and the first interphalangeal joint arthrodesis was performed in no case in the DMTO group and one case in the scarf group, with no significant difference between the two groups (P = 0.3527 and 0.3636, respectively). The operative time was significantly shorter in the DMTO group than in the scarf group (176.0 [150.5–199.5] minutes vs. 210.0 [198.8–239.3] minutes, P = 0.0002).
Table 1Demographic data, preoperative radiographic measurements, and surgical information of patients
DMTO (n=21)
Scarf (n=26)
P-value
Age, years
67.0 (59.5–72.5)
71.0 (60.8–73.5)
0.5624
BMI, kg/m2
20.7 (18.1–23.9)
20.6 (18.9–23.1)
0.5071
Medical history
Diabetes mellitus
1 (5%)
2 (8%)
0.6828
Chronic kidney disease
0 (0%)
1 (4%)
0.3636
Current smoker
0 (0%)
3 (12%)
0.1077
Disease duration, years
26.0 (15.5–34.0)
18.0 (10.3–34.5)
0.3964
MMP-3, ng/mL
59.0 (40.4–108.1)
60.4 (32.4–149.9)
0.9865
DAS28-CRP
2.1 (1.9–2.8)
2.2 (1.8 - 2.8)
0.9820
Medications
Methotrexate
17 (81%)
19 (73%)
0.5261
Biological or targeted synthetic DMARDs
5 (24%)
7 (27%)
0.8088
Prednisolone or other glucocorticoids
9 (43%)
9 (35%)
0.5634
HV angle, degree
39.0 (28.0–49.5)
44.0 (40.3–52.8)
0.0781
M1M2 angle, degree
14.0 (9.5–17.0)
16.0 (13.0–19.0)
0.0789
1-2 difference, mm
2.4 (1.1–4.6)
3.2 (1.8–5.9)
0.2997
Hardy grade (I:II:III:IV:V:VI:VII)
0:0:0:4:6:4:7
0:0:0:0:6:10:10
0.0890
AOFAS score
42.0 (29.0–57.0)
40.5 (34.0–53.3)
0.9532
Additional procedures to hallux
Akin
2 (10%)
5 (19%)
0.3527
IPJ desis
0 (0%)
1 (4%)
0.3636
Operative time, min
176.0 (150.5–199.5)
210.0 (198.8–239.3)
0.0002
DMTO: distal metatarsal telescoping osteotomy; BMI: body mass index; MMP-3: matrix metalloproteinase-3; DAS: disease activity score; CRP: C-reactive protein; HV: hallux valgus; M1M2: intermetatarsal between first and second, 1-2 difference: the differences in the length between the first and the second metatarsal; AOFAS, American Orthopaedic Foot and Ankle Society; IPJ, interphalangeal joint.
P-values in bold type indicate statistically significant differences.
Postoperative results of the clinical and radiographic outcomes
The results of the comparisons of the postoperative clinical and radiographic outcomes are shown in Table 2. Both the DMTO and scarf groups showed significant improvement after the procedures in the HV angle, M1M2 angle, Hardy grade, and AOFAS scores. The postoperative HV angle was significantly lower in the DMTO group than in the scarf group (10.0 [5.0–17.5] degrees vs. 16.0 [13.3–23.3] degrees, P = 0.0156). Other postoperative radiographic parameters, including the M1M2 angle, 1-2 difference, Hardy grade, and postoperative AOFAS score showed no significant differences between the two groups. The postoperative SAFE-Q score showed no significant difference in any subscale except for the better outcome in the DMTO group compared to the scarf group in the pain- and pain-related subscales (86.7 [74.7–100.0] vs. 70.0 [63.4–81.9], P = 0.0009). The postoperative observation period was significantly longer in the DMTO group (51.0 [42.0–54.0] months) than in the scarf group (28.0 [20.3–36.0] months, P < 0.0001). The comparison of the corrective amount of radiographic parameters and AOFAS score between the two groups showed no significant differences.
Table 2Postoperative clinical and radiographic outcomes
DMTO (n=21)
Scarf (n=26)
P-value
Postoperative data
HV angle, degree
10.0 (5.0–17.5)
16.0 (13.3–23.3)
0.0156
M1M2 angle, degree
9.0 (6.0–12.5)
10.0 (7.0–15.0)
0.4215
1-2 difference, mm
2.8 (0.8–6.5)
3.2 (1.2–6.2)
0.6219
Hardy grade (I:II:III:IV:V:VI:VII)
0:2:11:5:2:1:0
0:2:12:6:4:2:0
0.4721
AOFAS score
77.0 (71.0–81.0)
75.0 (69.3–82.0)
SAFE-Q
Pain and pain-related
86.7 (74.7–100.0)
70.0 (63.4–81.9)
0.0009
Physical functioning and daily living
77.3 (58.0–93.3)
68.2 (44.9–86.4)
0.3916
Social functioning
79.2 (33.4–100.0)
85.5 (54.2–100.0)
0.7991
Shoe-related
58.4 (41.7–83.4)
50.0 (33.4–68.8)
0.1764
General health and well-being
85.0 (70.0–100.0)
70.0 (50.0–100.0)
0.0924
Postoperative followed-up period, months
51.0 (42.0–54.0)
28.0 (20.3–36.0)
< 0.0001
Corrective amount of radiographic measures and AOFAS score
HV angle, degree
24.0 (18.5–36.5)
27.5 (17.0–34.3)
0.9873
M1M2 angle, degree
5.0 (0.0–8.0)
6.0 (2.8–8.3)
0.3187
1-2 difference, mm
−0.2 (−3.7–2.6)
0.3 (−2.3–1.7)
0.8446
Hardy grade
No change
1 (5%)
2 (8%)
0.5468
1 grade down
1 (5%)
4 (15%)
2 grade down
6 (29%)
7 (27%)
3 grade down
10 (48%)
7 (27%)
4 grade down
3 (14%)
6 (23%)
> 5 grade down
0 (0%)
0 (0%)
AOFAS score
31.0 (24.0–48.0)
34.0 (22.8–41.5)
0.7949
DMTO: Distal metatarsal telescoping osteotomy, HV: hallux valgus, M1M2: intermetatarsal between first and second, 1-2 difference: differences in the length between the first and the second metatarsal; AOFAS, American Orthopaedic Foot and Ankle Society; SAFE-Q, self-administered foot evaluation questionnaire
P-values in bold type indicate statistically significant differences.
The postoperative complications are listed in Table 3. Delayed wound healing was more frequently observed in the scarf group (23%) than in the DMTO group (10%); however, the difference was not statistically significant (P = 0.2190). Surgical site infections occurred only in the scarf group (8%); however, no significant difference was detected in the DMTO group (P = 0.1940). Hallux valgus recurrence occurred more frequently in the scarf group than in the DMTO group; however, the difference was not significant (31% vs. 19%, P = 0.3595). Avascular necrosis of the metatarsal head of the hallux were not observed in either group. Nonunion at the osteotomy site of the hallux occurred in two cases in the DMTO group and in no cases in the scarf group. One of these two cases with nonunion had a systemic complication of type I diabetes mellitus receiving insulin injection for more than 12 years. Another patient had a complication of rheumatoid vasculitis accompanied by recurring multiple skin ulcers as a possible risk factor for nonunion. Additional surgeries for nonunion were not performed in these two cases because the pain was not too severe to interfere with daily life and the patients did not require surgery.
Comparison of preoperative and postoperative data in severe HV cases
Fig. 2 shows the results of the preoperative and postoperative outcomes in patients with severe preoperative HV. The HV angle, M1M2 angle, and AOFAS score improved significantly after both the DMTO and scarf procedures. The comparison of the postoperative HV angle, M1M2 angle, and AOFAS score between the two groups showed no significant differences (P = 0.8258, 0.8619, 0.3708, and 0.1550, respectively).
Fig. 2Comparisons of pre- and postoperative data in severe hallux valgus (HV) cases. HV angle (A), intermetatarsal angle between the first and second metatarsal (M1M2 angle) (B), first and second metatarsal length differences (1-2 differences) (C), and the American Orthopaedic Foot and Ankle Society (AOFAS) score (D). Pre: preoperative, Post: postoperative, DMTO: Distal metatarsal telescoping osteotomy.
In this research, the short-term outcomes after the joint-preserving arthroplasties for rheumatoid HV deformity were compared between DMTO and scarf osteotomy procedures. Contrary to our hypothesis, the clinical and radiographic outcomes were generally comparable between the two procedures except for a significantly longer operative time for the scarf procedure. The subgroup analysis limited to cases with preoperative severe HV deformity also demonstrated no significant differences in the clinical and radiological outcomes between the two procedures.
Scarf osteotomy is a well-established and commonly used surgical method for moderate and severe HV deformities in non-arthritic joints; however, there are a limited number of studies reporting its outcomes in patients with RA.
Outcomes of scarf and akin osteotomy with intra-articular stepwise lateral soft tissue release for correcting hallux valgus deformity in rheumatoid arthritis.
A horizontal osteotomy used in the scarf procedure is beneficial in terms of the allowance of significant translation of the fragment, mechanical stability, and versatility in both rotational and translational corrections. However, this procedure is technically demanding and requires extensive bone exposure. Some specific complications, including troughing or fracture of the metatarsal, are known in scarf osteotomy, especially with fragile bones, such as osteoporosis and rheumatoid arthritis.
On the other hand, the distal osteotomies represented by Mitchell's osteotomy and distal Chevron osteotomy are not as technically demanding as scarf osteotomy and are less invasive with limited bony exposure. Distal procedures are generally preferred for mild to moderate HV because of their limited corrective ability for severe HV.
In the present study, the DMTO had sufficient correction and improved the function similar to scarf osteotomy even in cases with preoperative severe HV deformity. We considered that the shortening of the first metatarsal in DMTO might contributed to the effectiveness of correction in severe deformities by relieving tension of the surrounding structures, especially the adductor.
The procedures involving the shortening of the first metatarsal, such as Mitchell's osteotomy are known to be likely to have transfer metatarsalgia as the common complication.
The previous study which measured the plantar pressure distribution after Mitchell's osteotomy and scarf osteotomy demonstrated the increased mean and peak pressure under the second and third metatarsal heads only in the former procedure.
Another study investigated the change in the plantar pressure distribution after the modified Mitchell's osteotomy for the hallux and shortening oblique osteotomy for the lateral four metatarsals. This study demonstrated a significant decrease in peak pressure at the second and third MTP joints compared to the preoperative condition, suggesting that the overload at the lateral metatarsal heads caused by the shortened hallux could be avoided by shortening the lateral metatarsals.
The combination of modified Mitchell's osteotomy and shortening oblique osteotomy for patients with rheumatoid arthritis: an analysis of changes in plantar pressure distribution.
The retrospective comparative study between the cases of modified Mitchell's osteotomy with and without lesser metatarsal osteotomy according to the Helal's method demonstrated that the combination use of oblique lesser metatarsal osteotomy reduced the postoperative occurrence of plantar callosity or metatarsalgia (14.7% vs. 53.1%, P < 0.0005).
In the cases with RA, the MTP joints of the lesser toes are often dislocated and require shortening of the metatarsals to reduce the dislocation. Therefore, the DMTO procedure, which is inevitably accompanied by shortening of the first metatarsal, is considered to be compatible with RA forefoot deformities.
Nonunion is a major complication after metatarsal osteotomy, and its rate is reportedly up to 5.0% among joint-preserving surgeries in patients with RA.
No significant difference was observed in the nonunion rate between the DMTO and scarf groups in the present study. However, a considerable number of subjects in the DMTO group (10%) had nonunion at the osteotomy site of the hallux in contrast to 0% in the scarf group. Because two cases with nonunion had some risk factors influencing bone union, the accumulated surgical cases will be required to conclude whether DMTO is accompanied by a higher risk of nonunion compared to the other procedures. We consider that some attention should be paid when DMTO is performed in cases with a high risk of nonunion, such as more rigid fixation than a K-wire, delay in timing of the K-wire removal, and more careful instructions for patients about postoperative ambulation.
Avascular necrosis (AVN) of the hallux metatarsal head is a known complication after distal osteotomy in HV surgery.
Metatarsal osteotomy interrupts the intraosseous blood supply to the metatarsal head, and the metatarsal head is mainly supplied by branches from the first dorsal metatarsal, first plantar metatarsal, and medial plantar arteries forming a plexus in the plantar lateral neck of the metatarsal. The plantar exit of the osteotomy located proximal to the capsular attachment is vital to protect the plantar blood supply and avoid AVN.
With this precaution, no patient in the present study developed AVN of the first metatarsal head.
Our study has some limitations. First, the sample size was small, which reduces the power of the study. Second, this was a retrospective study and the postoperative observation period was different between groups. To minimize the risk of selection bias, consecutive sampling for both the DMTO and scarf groups was performed and over 70% of patients were recruited during the targeted period. Third, the procedures were performed by several surgeons. However, the surgeons in the present study were all experienced with at least several years of experience as rheumatic surgeons and applied the same technique. Finally, the length of follow-up was relatively short. Considering the progressive nature of RA, a longer follow-up period is necessary to establish our findings.
Conclusion
In conclusion, this study demonstrated that DMTO provided good postoperative clinical and radiographic outcomes comparable to scarf osteotomy with less invasiveness for HV deformity in patients with RA. It has also been demonstrated that DMTO can be successfully performed for cases with HV angles greater than 40°. The DMTO may be considered as an alternative treatment method for HV deformity in patients with RA, especially in cases with lesser toe deformities that require shortening of the metatarsals.
Disclosure statements
Funding/Sponsorship: This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors.
Institutional Ethical Committee Approval: This study was performed with the approval of the relevant ethics committee at Tokyo Metropolitan Bokutoh Hospital (approval No. 02-122).
Author contribution:Study conception and design: Makabe, Nagase, Nishikawa, Uchida; Acquisition of data: Makabe; Analysis and interpretation of data: Makabe, Matsumoto, Tanaka; Drafting of manuscript: Makabe, Matsumoto, Nagase
Informed Patient Consent
Written informed consent was obtained from all participants.
Declaration of competing interests
None.
Acknowledgment
None.
References
Matsumoto T
Nishino J
Izawa N
Naito M
Hirose J
Tanaka S
et al.
Trends in treatment, outcomes, and incidence of orthopedic surgery in patients with rheumatoid arthritis: an observational cohort study using the Japanese National Database of Rheumatic Diseases.
Outcomes of scarf and akin osteotomy with intra-articular stepwise lateral soft tissue release for correcting hallux valgus deformity in rheumatoid arthritis.
The combination of modified Mitchell's osteotomy and shortening oblique osteotomy for patients with rheumatoid arthritis: an analysis of changes in plantar pressure distribution.
00111-2&id=gr1.jpg){kind=link}
00111-2&id=gr2.jpg){kind=link}