Nonunion after medial malleolar osteotomy in total ankle arthroplasties for severe varus deformity: a report of 3 cases.

Of the three ankles after total ankle arthroplasty (TAA) with medial malleolar osteotomy for severe varus deformity (talar varus tilt >10°), two failed in varus migration of the tibial component. In these two cases, tibial osteotomy was performed with varus alignment of 5°and 2°, and with medially shifted placement of tibial component, while one ankle showed no migratoin of prostheses after 5 years, even with nonunion. In this case, tibial osteotomy was performed with a valgus alignment of 4°. Internal fixation after medial malleolar osteotomy should be done for severe varus cases. Medially shifted placement of tibial component should be avoided. Fortunately, the failure did not occur in a case of valgus of the distal tibia. Valgus tibial osteotomy might help to reduce the collision of the talus against the medial malleolus.

Midterm Outcomes After Total Knee Arthroplasty With Lateral Approach for Valgus Knee Deformity in Patients With Rheumatoid Arthritis.

Background Valgus knee deformity is often seen in rheumatoid arthritis (RA) cases. Usually, the medial approach has been often utilized for total knee arthroplasty (TKA), even in valgus deformity cases; however, the medial approach is feared to induce further instability in the medial side because it could further break the soft tissue structure, including medial collateral ligament (MCL) and medial patellofemoral ligament (MPFL). Consequently, loosening of the implant, recurrence of valgus knee deformity, and pain due to instability might be induced in the early period after surgery. In this study, a lateral approach for TKA against valgus deformity in RA cases was utilized to avoid further damage on the medial side. Methods Eleven valgus knees in 10 patients with RA (mean age, 61.1 years; mean follow-up, 33.1 months) underwent primary TKA with the lateral approach. Iliotibial band (ITB) dissection and/or peroneal nerve release were performed if necessary. Radiological and clinical investigations were evaluated pre- and postoperatively. Results The average operating time was 106 minutes, which was no longer compared with the time after the medial approach described previously. The extension angle was significantly improved from -15.0 ± 10.2 to -5.5 ± 4.2 degrees (P = 0.03), while the flexion angle showed no significant change (from 111.8 ± 15.9 to 115.0 ± 13.2 degrees). The hip-knee-ankle angle (HKA) was also significantly corrected from -9 ± 4.9 to 0.4 ± 1.7 degrees (P < 0.001). The 2011 Knee Score System (KSS) scores were significantly improved from 6.9 ± 3.4 to 21.5 ± 2.9 (P < 0.001) in symptoms, from 15.6 ± 2.7 to 31.1 ± 4.1 (P < 0.001) in satisfaction, and from 31.5 to 59.5 (P < 0.01) in activity. Conclusion Midterm outcomes after lateral approach TKA were good, and knee alignment was significantly improved. The lateral approach TKA for valgus deformity in patients with RA was not complicated and difficult because it required no additional operating time compared with the medial approach. From the perspective of preventing further damage to the soft tissue structure on the medial side, the lateral approach was meaningful for valgus deformity in patients with RA.

Reverse V-shaped osteotomy for ankylosing rocker-bottom foot deformity in patients with rheumatoid arthritis. A report of 3 cases.

This study evaluated reverse V-shaped osteotomy for ankylosing rocker-bottom foot deformity in patients with rheumatoid arthritis. We experienced 3 feet: rheumatoid rocker-bottom deformities with painful and/or infectious bony prominence towards the bottom of the foot, treated with a reverse V-shaped osteotomy in the mid-hindfoot. In all three cases, significant correction was achieved with restoration of the medial longitudinal arch, and improvement in clinical scores was confirmed. Reverse V-shaped osteotomy has the potential to be a useful and definitive procedure for ankylosing rocker-bottom deformity in patients with rheumatoid arthritis.

Early full weight-bearing and gait exercise after cemented total ankle arthroplasty with modified antero-lateral approach.

BACKGROUND: According to the conventional postoperative procedure after total ankle arthroplasty (TAA) against end-stage osteoarthritis (OA) and rheumatoid arthritis (RA), mobilization and weight-bearing is currently started after completion of wound healing. Recently, early mobilization for dorsiflexion after TAA with modified antero-lateral approach was reported to be feasible and safe. To investigate the further possibility of expediting rehabilitation, this study evaluated the feasibility and safety of early full weight-bearing and gait exercise after cemented TAA utilizing a modified antero-lateral approach. MATERIALS AND METHODS: This retrospective, observational study investigated 23 consecutive ankles (OA: 14 ankles, RA: 9 ankles) that had received cemented TAA with a modified antero-lateral approach. These ankles were divided into three groups [1. conventional postoperative protocol: 8 ankles, 2. early dorsiflexion protocol: 7 ankles, 3. early dorsiflexion+full weight-bearing protocol: 8 ankles]. In group 3, after early dorsiflexion mobilization (day 3), full weight-bearing/gait exercise was started from 7 days after surgery (10 days after if malleolar osteotomy was added). Postoperative wound complications were observed and recorded. Number of days for hospitalization was also evaluated. Range of motion (ROM) of dorsiflexion/plantar flexion was measured. Patients also completed a self-administered foot evaluation questionnaire (SAFE-Q) and the scale of Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot score preoperatively and at final follow-up. RESULTS: No postoperative complications related to wound healing were observed even after early full weight-bearing and gait exercise. Days for hospitalization was significantly shortened in early full weight-bearing and gait exercise group (group 3) from 35-38 days to 24 days. ROM for both dorsiflexion and plantar flexion significantly increased in group 3, furthermore all indices of SAFE-Q score also showed stronger significant improvement in group 3. JSSF score improved significantly after TAA in all groups. CONCLUSION: Within this small number of cases, early full weight-bearing and gait exercise from 7 days after cemented TAA was feasible and safe with the modified antero-lateral approach. Combination of early dorsiflexion mobilization and weight-bearing/gait exercise contributed to shortening the hospitalization day, and improving ROM for both dorsiflexion and plantar flexion after surgery. Innovations in postoperative procedures for rehabilitation after TAA can be expected.

An investigation of the differential therapeutic effects of romosozumab on postmenopausal osteoporosis patients with or without rheumatoid arthritis complications: a case-control study.

The impact of ROMO on the width of anabolic windows and the increase in BMD was reduced in the RA group compared to the non-RA group, and this reduction was associated with correlations to RA-related factors. PURPOSE: To investigate the effects of romosozumab (ROMO) in postmenopausal osteoporosis, with and without comorbid rheumatoid arthritis (RA). METHODS: In this retrospective, case-controlled, multicenter study, 171 postmenopausal patients who did not receive oral glucocorticoid, comprising 59 in the RA group and 121 in the non-RA group, received uninterrupted ROMO treatment for 12 months. Propensity score matching was employed to ensure comparability in clinical backgrounds, resulting in 41 patients in each group. Baseline characteristics were as follows: overall (mean age, 76.3 years; T-score of lumbar spine (LS), - 3.0; 45.1% were treatment-naive for osteoporosis); RA group (anti-cyclic citrullinated peptide antibody (ACPA) positivity, 80.5%; titer, 206.2 U/ml; clinical disease activity index (CDAI), 13.6; health assessment questionnaire disability index (HAQ-DI), 0.9). Bone mineral density (BMD) and serum bone turnover markers were monitored over a 12-month period. RESULTS: The rate of increase in the bone formation marker, PINP, and the rates of decrease in the bone resorption marker, TRACP-5b, exhibited a trend toward smaller changes in the RA group compared to the non-RA group, implying a smaller anabolic window. After 12 months, the RA group displayed lower BMD increases in the LS (9.1% vs. 12.6%; P = 0.013) and total hip (2.4% vs. 4.8%; P = 0.025) compared to the non-RA group. Multiple regression analysis in the all RA group (n = 59) for the association between RA-specific factors and 12-month BMD changes revealed negative correlations between ACPA titer and LS BMD and between HAQ-DI and femoral neck BMD. CONCLUSIONS: The efficacy of ROMO may be attenuated by RA-related factors.

Anti-NF-κB peptide derived from nuclear acidic protein attenuates ovariectomy-induced osteoporosis in mice.

NF-κB is a transcription factor that is activated with aging. It plays a key role in the development of osteoporosis by promoting osteoclast differentiation and inhibiting osteoblast differentiation. In this study, we developed a small anti-NF-κB peptide called 6A-8R from a nuclear acidic protein (also known as macromolecular translocation inhibitor II, Zn2+-binding protein, or parathymosin) that inhibits transcriptional activity of NF-κB without altering its nuclear translocation and binding to DNA. Intraperitoneal injection of 6A-8R attenuated ovariectomy-induced osteoporosis in mice by inhibiting osteoclast differentiation, promoting osteoblast differentiation, and inhibiting sclerostin production by osteocytes in vivo with no apparent side effects. Conversely, in vitro, 6A-8R inhibited osteoclast differentiation by inhibiting NF-κB transcriptional activity, promoted osteoblast differentiation by promoting Smad1 phosphorylation, and inhibited sclerostin expression in osteocytes by inhibiting myocyte enhancer factors 2C and 2D. These findings suggest that 6A-8R has the potential to be an antiosteoporotic therapeutic agent with uncoupling properties.

Quick Transposition of ReBOSSIS-J® to the Host Bone Trabeculae Within One Month After Supplementing to the Harvest Site on the Calcaneus for Autologous Bone Grafting in a Rheumatoid Arthritis Case.

We present the case of a patient with rheumatoid arthritis who underwent talonavicular joint fusion using an autologous calcaneal bone graft. At the same time, the bony defect at the harvest site was supplemented with ReBOSSIS-J® [70% ß-TCP and 30% poly(L-lactide-co-glycolide)](ORTHOREBIRTH Co. Ltd., Kanagawa, Japan), a synthetic bioresorbable bone void filler for the repair of bony defects with handling characteristics similar to a cotton ball. Material resorption and new bone formation had already started one week postoperatively. Transposition to host bone trabeculae was almost completed by 26 days postoperatively. Very rapid reactive graft resorption, repair with new bone formation, and subsequently, most of the transformation to host bone trabeculae were confirmed. ReBOSSIS-J® appears feasible to contribute to early heel weight-bearing exercise after foot or ankle surgery. In addition, preventing the fracture at the harvesting site of the calcaneal bone graft can also be expected.

Angioleiomyoma mimicking a swollen bursa on first metatarsophalangeal joint accompanying with hallux valgus deformity.

We present a case of a patient who underwent a modified scarf osteotomy and tumour excision based on a preoperative diagnosis of hallux valgus deformity and accompanying bursitis. Subsequent histopathological examination revealed that the tumour was an angioleiomyoma. While tumours around the first metatarsophalangeal (MTP) joint are typically associated with gouty nodules, infections, or swollen bursa (bursitis) in patients with hallux valgus deformity, the occurrence of soft tissue tumours in this area is rare. Moreover, angioleiomyoma is an even rarer form of soft tissue tumour and is seldom suspected prior to resection. To our knowledge, there have been no reports of angioleiomyoma arising in the first MTP joint. However, it is important to consider the possibility of an atypical tumour in cases where soft tissue masses are present, even in patients with hallux valgus deformity, and to perform at least imaging tests such as ultrasound and magnetic resonance imaging before surgery. This prospect should always be kept in mind.

Basic fibroblast growth factor promotes meniscus regeneration through the cultivation of synovial mesenchymal stem cells via the CXCL6-CXCR2 pathway.

OBJECTIVE: To investigate the efficacy of basic fibroblast growth factor (bFGF) in promoting meniscus regeneration by cultivating synovial mesenchymal stem cells (SMSCs) and to validate the underlying mechanisms. METHODS: Human SMSCs were collected from patients with osteoarthritis. Eight-week-old nude rats underwent hemi-meniscectomy, and SMSCs in pellet form, either with or without bFGF (1.0 × 106 cells per pellet), were implanted at the site of meniscus defects. Rats were divided into the control (no transplantation), FGF (-) (pellet without bFGF), and FGF (+) (pellet with bFGF) groups. Different examinations, including assessment of the regenerated meniscus area, histological scoring of the regenerated meniscus and cartilage, meniscus indentation test, and immunohistochemistry analysis, were performed at 4 and 8 weeks after surgery. RESULTS: Transplanted SMSCs adhered to the regenerative meniscus. Compared with the control group, the FGF (+) group had larger regenerated meniscus areas, superior histological scores of the meniscus and cartilage, and better meniscus mechanical properties. RNA sequencing of SMSCs revealed that the gene expression of chemokines that bind to CXCR2 was upregulated by bFGF. Furthermore, conditioned medium derived from SMSCs cultivated with bFGF exhibited enhanced cell migration, proliferation, and chondrogenic differentiation, which were specifically inhibited by CXCR2 or CXCL6 inhibitors. CONCLUSION: SMSCs cultured with bFGF promoted the expression of CXCL6. This mechanism may enhance cell migration, proliferation, and chondrogenic differentiation, thereby resulting in superior meniscus regeneration and cartilage preservation.

Early Resection of the Tibialis Anterior Tendon for Tendon Exposure After Total Ankle Arthroplasty to Prevent Deep Infection: A Report of Three Cases in Patients With Rheumatoid Arthritis.

Exposure of the tibialis anterior (TA) tendon with wound dehiscence after total ankle arthroplasty (TAA) with the anterior approach is a problematic complication, especially in rheumatoid arthritis (RA) patients. Once the TA tendon is exposed, the duration of wound healing is prolonged, and it could be a risk factor for deep infection. Thus, early resection of the TA tendon was evaluated for tendon exposure with wound dehiscence after TAA in RA patients. In this case report, three rheumatoid ankles that showed wound dehiscence with exposure of the TA tendon after TAA with the anterior approach are presented. Early resection of the TA tendon and debridement under local anesthesia were performed within two days after wound dehiscence. In all cases, wound healing was completed within two weeks after the treatment. Drop foot was not seen in any patients, and there was no difference between the pre and postoperative (1 year after TAA) range of dorsiflexion. Muscle strength for ankle dorsiflexion was also maintained. In conclusion, early resection of the TA tendon appears to be a useful option for undesirable tendon exposure with wound dehiscence to prevent deep infection and prolonged wound healing after total ankle arthroplasty in RA patients.

Early mobilization of dorsiflexion from 3 days after cemented total ankle arthroplasty with modified antero-lateral approach.

BACKGROUND: According to the conventional postoperative procedure after total ankle arthroplasty (TAA), mobilization is currently started after completion of wound healing. To investigate the possibility of expediting rehabilitation, this study evaluated the feasibility and safety of early mobilization of dorsiflexion after cemented TAA utilizing a modified antero-lateral approach. MATERIALS AND METHODS: This retrospective, observational study investigated 14 consecutive ankles that had received cemented TAA. Mobilization of dorsiflexion was started from 3 days after surgery. Postoperative wound complications including blister formation, eschar formation, wound dehiscence, peri-incisional decreased sensation were observed and recorded. Range of motion (ROM) of dorsiflexion/plantar flexion was measured. Patients also completed a self-administered foot evaluation questionnaire (SAFE-Q) and the scale of Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot score preoperatively and at final follow-up. RESULTS: No postoperative complications related to wound healing were observed. ROM for dorsiflexion, SAFE-Q score, and JSSF score improved significantly after TAA. CONCLUSION: Within this small number of cases, early mobilization of dorsiflexion from 3 days after cemented TAA was feasible and safe with the modified antero-lateral approach. Innovations in postoperative procedures for rehabilitation after TAA can be expected.

Modified scarf osteotomy with capsular interposition as salvage for resection or silicone implant arthroplasty in patients with rheumatoid arthritis. A report of three cases.

This study investigated modified scarf osteotomy as a salvage procedure after resection arthroplasty or silicone implant arthroplasty to preserve mobility of the first metatarsophalangeal (MTP) joint after hallux valgus surgery in patients with rheumatoid arthritis (RA). We investigated three feet with rheumatoid forefoot deformities that showed recurrence of forefoot deformity or breakage of the implant after resection or silicone implant arthroplasty in the first MTP joint. All feet were treated using modified scarf osteotomy with capsular interposition. All cases achieved obvious correction after modified scarf osteotomy despite resection of the first MTP joint and consequently showed both radiographic and clinical improvements. Modified scarf osteotomy offers potential as a definitive salvage procedure after resection arthroplasty or silicone implant arthroplasty for forefoot deformity in patients with RA, because the procedure can realign the first MTP joint obviously with preservation of the range of motion. Concomitant medial capsular interposition into the newly formed first MTP joint is also recommended where possible, to protect the edges of the proximal basal phalanx and distal first metatarsal and also to smoothen the motion of newly formed first MTP joint.

Improvement of Knee Alignment and Function After Corrective Surgery for Hindfoot Deformity: A Report of 3 Cases.

CASE: Marked varus or valgus hindfoot deformities in 3 patients with ankle osteoarthritis or rheumatoid arthritis were treated by corrective surgery using total ankle arthroplasty or distal tibia oblique osteotomy. All cases achieved not only sufficient correction and satisfactory clinical/radiographic hindfoot improvement but also improvements in both knee alignment and function. CONCLUSION: Corrective surgery for hindfoot deformity can potentially change or improve ipsilateral knee alignment and function, representing an unexpected benefit of hindfoot realignment.

Characteristics of Intermetatarsal Angle Between the Second and Fifth Metatarsals (M2-M5A) in the Rheumatoid Foot.

BACKGROUND: Increasing of intermetatarsal angle between the first and second metatarsals (M1-M2A) has been reported as a risk factor for recurrence of hallux valgus (HV) deformity, on the other hand, increasing of intermetatarsal angle between the second and fifth metatarsals (M2-M5A) has been reported as a risk factor for resubluxation of the metatarsophalangeal (MTP) joint of the lesser toe after rheumatoid forefoot surgery. In this study, parameters related to increasing M2-M5A were investigated, as compared with M1-M2A and M1-M5A. METHODS: Radiographic parameters including M1-M2A, M1-M5A, and M2-M5A were retrospectively evaluated for 119 lower limbs from 68 patients with rheumatoid arthritis (RA). To clarify the clinical importance of these intermetatarsal angles, relationships with results from the timed up-and-go (TUG) test were also investigated. RESULTS: M1-M5A showed no correlation with mid-hind foot parameters, whereas M1-M2A and M2-M5A correlated with valgus/varus parameters. An increased M1-M2A was associated with lateral shift of the loading axis in the tibial plafond, whereas an increased M2-M5A was associated with medial shift, but M1-M5A showed no associations. M2-M5A/M1-M2A was significantly lower (1.7) in the normal TUG group than in the delayed TUG group (2.8) (p=0.045). CONCLUSIONS: Different patterns of spread are seen for the forefoot. One has a predominantly increased M1-M2A with lateral shift of the loading point in the tibial plafond, whereas the other has a predominantly increased M2-M5A with medial shift of the loading point in the tibial plafond. M2-M5A also should be calculated, and M2-M5A/M1-M2A might be meaningful in understanding physical mobility in RA patients.

Modified Scarf Osteotomy with Medial Capsular Interposition Combined with Metatarsal Shortening Offset Osteotomy: A Comparison of Patients with Noninflammatory Arthritis and Rheumatoid Arthritis of the Foot.

BACKGROUND: Patients who have noninflammatory arthritis of the feet may develop destructive changes on the first metatarsal head and painful dislocation of the metatarsophalangeal (MTP) joint of 1 or more lesser toes. This aim of this study was to compare feet with noninflammatory arthritis and those with rheumatoid arthritis (RA) with respect to the clinical and radiographic outcomes after treatment of these destructive deformities with a modified Scarf osteotomy with medial capsular interposition into the newly formed first MTP joint, combined with metatarsal shortening offset osteotomy. METHODS: A retrospective observational study of 93 feet (31 with noninflammatory arthritis and 62 with RA) was performed. Hallux and lesser-toe scores on the Japanese Society for Surgery of the Foot (JSSF) scoring system, a self-administered foot evaluation questionnaire (SAFE-Q), and preoperative and postoperative radiographic parameters were evaluated. RESULTS: There were significant improvements at the time of the final follow-up in the mean scores on the hallux and lesser-toe scales of the JSSF system and in the SAFE-Q score. The postoperative JSSF lesser-toes function score was better for the feet with noninflammatory arthritis feet than the feet with RA. There was no significant difference in the hallux valgus angle (HVA) between 1 month postoperatively and the final follow-up for both groups. Furthermore, the HVA showed a strong correlation between the 1-month and final follow-up values. CONCLUSIONS: The combination of the modified Scarf osteotomy with medial capsular interposition and shortening metatarsal offset osteotomy was useful and safe in feet with noninflammatory arthritis. The HVA at 1 month after surgery is useful to predict the HVA within 5 years after surgery. The postoperative clinical score for the lesser toes was better in the feet with noninflammatory arthritis. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Combination of Modified Scarf Osteotomy and Metatarsal Shortening Offset Osteotomy for Rheumatoid Forefoot Deformity.

With the progress of medical treatment for rheumatoid arthritis (RA), several joint-preserving forefoot surgical procedures have been established and performed. In this situation, we have been choosing the combined surgery: modified scarf osteotomy for the great toe and metatarsal shortening offset osteotomy for the lesser toes in RA cases. A retrospective observational study of 53 RA patients (mean follow-up period: 4.6 years) who underwent the surgery was completed. RA foot ankle scores were assessed, using the Japanese Society for Surgery of the Foot (JSSF) standard rating system, and a self-administered foot evaluation questionnaire (SAFE-Q) was also checked to evaluate clinical outcomes. For radiological evaluations, deformity parameters were measured using radiographs of the feet with weight-bearing. JSSF hallux and lesser toes scores and the SAFE-Q score showed significant improvement in all indices. HVA, M1-M2A, M1-M5A, M2-M5A, and sesamoid position were significantly improved after surgery. At the final follow-up, the hallux valgus deformity had recurred in 4 feet (7.5%), and hallux varus deformity had developed in 8 feet (15.1%). No case of recurrent hallux valgus deformity required revision surgery. Recurrence of dorsal dislocation/subluxation of the lesser toe MTP joint was seen in 6 feet (11.3%) after surgery. A combination of modified scarf osteotomy for the great toe and modified metatarsal shortening offset osteotomy for the lesser toes is one of the novel surgical procedures for rheumatoid forefoot deformity. Preoperative disease activity of RA negatively affected the clinical score of the hallux. The spread of M2-M5A was a risk factor for resubluxation of the lesser toe MTP joint.

Divergence in chondrogenic potential between in vitro and in vivo of adipose- and synovial-stem cells from mouse and human.

BACKGROUND: Somatic stem cell transplantation has been performed for cartilage injury, but the reparative mechanisms are still conflicting. The chondrogenic potential of stem cells are thought as promising features for cartilage therapy; however, the correlation between their potential for chondrogenesis in vitro and in vivo remains undefined. The purpose of this study was to investigate the intrinsic chondrogenic condition depends on cell types and explore an indicator to select useful stem cells for cartilage regeneration. METHODS: The chondrogenic potential of two different stem cell types derived from adipose tissue (ASCs) and synovium (SSCs) of mice and humans was assessed using bone morphogenic protein-2 (BMP2) and transforming growth factor-ß1 (TGFß1). Their in vivo chondrogenic potential was validated through transplantation into a mouse osteochondral defect model. RESULTS: All cell types showed apparent chondrogenesis under the combination of BMP2 and TGFß1 in vitro, as assessed by the formation of proteoglycan- and type 2 collagen (COL2)-rich tissues. However, our results vastly differed with those observed following single stimulation among species and cell types; apparent chondrogenesis of mouse SSCs was observed with supplementation of BMP2 or TGFß1, whereas chondrogenesis of mouse ASCs and human SSCs was observed with supplementation of BMP2 not TGFß1. Human ASCs showed no obvious chondrogenesis following single stimulation. Mouse SSCs showed the formation of hyaline-like cartilage which had less fibrous components (COL1/3) with supplementation of TGFß1. However, human cells developed COL1/3+ tissues with all treatments. Transcriptomic analysis for TGFß receptors and ligands of cells prior to chondrogenic induction did not indicate their distinct reactivity to the TGFß1 or BMP2. In the transplanted site in vivo, mouse SSCs formed hyaline-like cartilage (proteoglycan+/COL2+/COL1-/COL3-) but other cell types mainly formed COL1/3-positive fibrous tissues in line with in vitro reactivity to TGFß1. CONCLUSION: Optimal chondrogenic factors driving chondrogenesis from somatic stem cells are intrinsically distinct among cell types and species. Among them, the response to TGFß1 may possibly represent the fate of stem cells when locally transplanted into cartilage defects.

Effects of prior osteoporosis treatment on 12-month treatment response of romosozumab in patients with postmenopausal osteoporosis.

OBJECTIVES: To investigate the effects of prior treatment and determine the predictors of a 12-month treatment response of romosozumab (ROMO) in 148 patients with postmenopausal osteoporosis. METHODS: In this prospective, observational, and multicenter study, treatment naïve patients (Naïve; n=50) or patients previously treated with bisphosphonates (BP; n=37) or denosumab (DMAb; n=45) or teriparatide (TPTD; n=16) (mean age, 75.0 years; T-scores of the lumbar spine [LS] -3.2 and total hip [TH] -2.6) were switched to ROMO due to insufficient effects of prior treatment. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 12 months. RESULTS: At 12 months, changes in LS BMD were Naïve (18.2%), BP (10.2%), DMAb (6.4%), and TPTD (11.2%) (P<0.001 between groups) and changes in TH BMD were Naïve (5.6%), BP (3.3%), DMAb (0.6%), and TPTD (4.4%) (P<0.01 between groups), respectively. In all groups, the LS BMD significantly increased from baseline at 6 and 12 months, although only the DMAb group failed to obtain a significant increase in TH BMD during 12-month treatment. Mean values of N-terminal type I procollagen propeptide (PINP; µg/L) from baseline → 1 month → 12 months were Naïve (67.9 → 134.1 → 51.0), BP (32. 2 → 81.7 → 40.9), DMAb (30.4 → 56.2 → 75.3), and TPTD (97.4 → 105.1 → 37.1), and those of isoform 5b of tartrate-resistant acid phosphatase (TRACP-5b; mU/dL) were Naïve (500.4 → 283.8 → 267.1), BP (273.4 → 203.1 → 242.0), DMAb (220.3 → 246.1 → 304.8), and TPTD (446.6 → 305.1 → 235.7), respectively. Multiple regression analysis revealed that the significant predictors of BMD change at 12 months were difference of prior treatment (r=-2.8, P<0.001) and value of PINP at 1 month (r=0.04, P<0.01) for LS, and difference of prior treatment (r=-1.3, P<0.05) and percentage change of TRACP-5b at 1 month (r=-0.06, P<0.05) for TH. CONCLUSIONS: The early effects of ROMO on LS and TH BMD increase at 12 months were significantly affected by the difference of prior treatment and are predicted by the early change in bone turnover markers.