Automated diagnosis of flatfoot using cascaded convolutional neural network for angle measurements in weight-bearing lateral radiographs.

OBJECTIVES: Diagnosis of flatfoot using a radiograph is subject to intra- and inter-observer variabilities. Here, we developed a cascade convolutional neural network (CNN)-based deep learning model (DLM) for an automated angle measurement for flatfoot diagnosis using landmark detection. METHODS: We used 1200 weight-bearing lateral foot radiographs from young adult Korean males for the model development. An experienced orthopedic surgeon identified 22 radiographic landmarks and measured three angles for flatfoot diagnosis that served as the ground truth (GT). Another orthopedic surgeon (OS) and a general physician (GP) independently identified the landmarks of the test dataset and measured the angles using the same method. External validation was performed using 100 and 17 radiographs acquired from a tertiary referral center and a public database, respectively. RESULTS: The DLM showed smaller absolute average errors from the GT for the three angle measurements for flatfoot diagnosis compared with both human observers. Under the guidance of the DLM, the average errors of observers OS and GP decreased from 2.35° ± 3.01° to 1.55° ± 2.09° and from 1.99° ± 2.76° to 1.56° ± 2.19°, respectively (both p < 0.001). The total measurement time decreased from 195 to 135 min in observer OS and from 205 to 155 min in observer GP. The absolute average errors of the DLM in the external validation sets were similar or superior to those of human observers in the original test dataset. CONCLUSIONS: Our CNN model had significantly better accuracy and reliability than human observers in diagnosing flatfoot, and notably improved the accuracy and reliability of human observers. KEY POINTS: • Development of deep learning model (DLM) that allows automated angle measurements for landmark detection based on 1200 weight-bearing lateral radiographs for diagnosing flatfoot. • Our DLM showed smaller absolute average errors for flatfoot diagnosis compared with two human observers. • Under the guidance of the model, the average errors of two human observers decreased and total measurement time also decreased from 195 to 135 min and from 205 to 155 min.

Distal chevron metatarsal osteotomy is a viable treatment option for hallux valgus with metatarsus adductus-multicentre retrospective study.

PURPOSE: The purpose of this study was to evaluate the radiographic and clinical outcomes of patients with hallux valgus (HV) with concomitant metatarsus adductus (MA) treated with distal chevron metatarsal osteotomy (DCMO), without any procedure for the second or third metatarsal. METHODS: A multicentre retrospective study involving four hospitals was conducted. A total of 45 feet from 38 patients who had received DCMO for HV with MA with at least one year post-operative follow-up were analysed. HV angle (HVâ), inter-metatarsal angle (IMâ), MA angle (MAâ), and the lateral sesamoid grade were measured. Foot function index (FFI) and visual analogue scale (VAS) were recorded. Patients were divided into mild (18° ≤ MAâ < 20°) and moderate (20° ≤ MAâ) MA groups, and results were compared. RESULTS: The mean HVâ and IMâ improved significantly from 35.1° and 14.4° pre-operatively to 10.6° and 7.1° one year post-operatively (p < 0.001). There were no differences in pre-operative HVâ, IMâ, or the sesamoid grade, and also no difference in post-operative HVâ or the sesamoid grade between mild and moderate MA groups. Only the mean post-operative IMâ showed a difference between the two groups (8.3° vs. 6.3°; p = 0.019). All clauses of FFI and VAS improved significantly (p < 0.001). When the extent of improvement was compared between the two groups, there were no significant differences in any category (p > 0.05). The total rate of recurrence (HVâ ≥ 20°) was 11.1% (5/45), and although the moderate group (4/29, 13.8%) had a higher proportion than the mild group (1/16, 6.3%), this was not statistically significant (p = 0.641). CONCLUSION: DCMO for patients with HV with MA had satisfactory radiographic and clinical outcomes with minimal recurrence. Except in cases of severe combined deformity, we recommend performing DCMO alone without any additional procedure or manipulation of the other metatarsals as a viable treatment option.

Treatment of Recurrent Peroneal Tendon Dislocation by Peroneal Retinaculum Reattachment Without Fibular Groove Deepening.

There are numerous studies recommending fibular groove deepening in the surgical treatment of peroneal tendon dislocation; however, there are some disadvantages to fibular groove deepening procedures. In this study, we evaluated the results of anatomic reattachment of the peroneal retinaculum without fibular groove deepening as a treatment for traumatic peroneal tendon dislocation. Thirty-six patients with recurrent peroneal tendon dislocation, who underwent retinaculum repair without a fibular groove deepening procedure performed by 2 surgeons between March 2004 and March 2017, were enrolled in this study. Resubluxation of tendon, pain on inversion and eversion power of the ankle were monitored. The range of motion of inversion and eversion were measured and then compared to that of the contralateral side. American Orthopedic Foot and Ankle Society (AOFAS), visual analog scale (VAS), Foot Function Index (FFI) scores were obtained for all patients preoperatively and at the final follow-up. Postoperative complications such as infection, sural nerve injury, and recurrence were monitored. Thirty-four patients fully recovered without resubluxation of tendon. Two patients were injured again while playing soccer 6 months after the surgery and fast running 20 months after the surgery respectively. One patient had sural nerve injury. But the symptom was relieved at 6 months after the surgery. None of the patients had weakness of evertor. None of the patients had limited ankle motion. Mean AOFAS, VAS, FFI score improved significantly (p = .02, .01, .02). In conclusion, for the treatment of recurrent dislocation of the peroneal tendon reattachment of the superior retinaculum only without groove deepening followed by proper rehabilitation is sufficient.

Distal chevron osteotomy with lateral release for moderate to severe hallux valgus patients aged sixty years and over.

PURPOSE: To analyze the outcome of distal chevron metatarsal osteotomy (DCMO) with lateral release for moderate to severe hallux valgus patients aged 60 years or more. METHODS: Consecutive 77 DCMOs in 54 patients were evaluated. Average age at operation was 65.1 ± 4.3 (range 60~79) years; the mean follow-up period was 20.5 ± 14.2 (range 12~93) months. Hallux valgus angle (HVA), first to second inter-metatarsal angle (IMA), and lateral sesamoid grades were measured. Considering the weak bone quality of the patients, fixation failures such as pin migration, callus formation, delayed union, and first metatarsal bone shortening were reviewed. Osteoarthritis (OA) of the first metatarsophalangeal joint (MTPJ), limitation of 1st MTPJ motion (LOM), and transfer metatarsalgia were also reviewed. RESULTS: HVA, IMA, and sesamoid grades were improved at three months and final follow-up. The mean HVA was 36.9° ± 7.0° preoperatively and 6.8° ± 7.1° at final follow-up. The mean correction angle of HVA was 31.3° ± 8.5° at three months and 30.1° ± 8.9° at final follow-up. The mean IMA was 16.3° ± 3.0° pre-operatively and 7.7° ± 2.7° at final follow-up. Hallux varus deformity was observed in three feet. Instability of osteotomy site was observed in one foot. Mean metatarsal shortening length was 1.26 ± 2.1 mm at three month follow-up. There were no cases of transfer metatarsalgia after operation. OA was observed in four feet post-operatively. LOM was observed in ten feet (13.0%). There were no instances of re-fracture or avascular necrosis (AVN). CONCLUSION: Despite concerns about aggravation of OA and fixation failure, distal chevron osteotomy with lateral release was safe on patients aged 60 years and over.

Desmoplastic fibroblastoma mimicking tenosynovial giant cell tumor encasing a tendon of the foot.

Desmoplastic fibroblastoma is an uncommon, benign fibrous soft tissue tumor that usually occurs in the arms, shoulders, neck, hands, and feet in the fifth to seventh decades of life. In general, it is commonly located in the subcutaneous tissue and skeletal muscle. The authors report an unusual case of a desmoplastic fibroblastoma mimicking tenosynovial giant cell tumor encasing a tendon of the foot in a 72-year-old woman. Ultrasonography revealed an inhomogeneously hypoechoic lobulated soft tissue lesion completely wrapped around the extensor digitorum longus tendon. Color Doppler study revealed increased vascularity in the internal and peripheral portions of the lesion. Magnetic resonance imaging revealed a well-defined, lobulated soft tissue mass encasing the extensor digitorum longus tendon with predominantly isointense signal with some areas of hypointense signal on T1-weighted images, predominantly hyperintense signal with some areas of hypointense signal on T2-weighted images, and inhomogeneous enhancement on fat-suppressed contrast-enhanced T1-weighted images. Surgical excision was performed, and the mass was diagnosed on pathological examination as a desmoplastic fibroblastoma. There has been no previously published radiologic case of a desmoplastic fibroblastoma encasing a tendon of the foot in the literature.

Bone marrow aspirate concentrate and platelet-rich plasma enhanced bone healing in distraction osteogenesis of the tibia.

BACKGROUND: During lower limb lengthening, poor bone regeneration is a devastating complication. Several local or systemic applications have been used to promote osteogenesis, and biologic stimulations are gaining attention, but their utility has not been proven in this setting. QUESTIONS/PURPOSES: In patients undergoing bilateral tibial lengthening, we compared those receiving an osteotomy site injection of autologous bone marrow aspirate concentrate (BMAC) plus platelet-rich plasma (PRP) with those not receiving such an injection in terms of external fixator index (time in external fixation divided by amount of lengthening), full weightbearing index (time until a patient was permitted to do full weightbearing divided by amount of lengthening), four cortical healing indexes (time until each cortical union divided by amount of lengthening), and callus shape and type. METHODS: Twenty-two patients (44 tibias) undergoing bilateral tibial lengthening enrolled in this randomized trial. Two patients were excluded, one due to insufficient radiographic evaluation and one who was lost to followup, leaving 20 patients (40 segments) for inclusion. Ten patients (20 segments) received BMAC combined with PRP injection (treatment group) and 10 patients (20 segments) received no injection (control group). All patients underwent stature lengthening for familial short stature with the lengthening over nail technique. Autologous BMAC combined with PRP was injected at the tibial osteotomy site at the end of the index surgery. Mean distraction rates were similar between groups (0.75 mm/day in the treatment group versus 0.72 mm/day in the control group; p = 0.24). Full weightbearing was permitted when we observed radiographic evidence of healing at two cortices; this assessment was made by the surgeon who was blinded to the treatment each patient received. Minimum followup was 24 months (mean, 28 months; range, 24-34 months). RESULTS: There was no difference in mean external fixator index between groups. However, mean cortical healing indexes (anterior/posterior/medial/lateral) were 1.14/0.81/0.96/0.88 months/cm in the treatment group and 1.47/1.26/1.42/1.22 months/cm in the control group (all p < 0.001), showing faster healing in the treatment group at each cortex. Full weightbearing was permitted earlier in the treatment group than in the control group (index: 0.99 months/cm and 1.38 months/cm, respectively, p < 0.001). Callus shape and type were not different between groups. CONCLUSIONS: Autologous BMAC combined with PRP injection at the osteotomy site helped improve bone healing in distraction osteogenesis of the tibia, although the effect size was small. LEVEL OF EVIDENCE: Level I, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Subungual glomus cell proliferation in the toe: a case report.

Glomus tumors are rare benign neoplasms. They typically present with a triad of severe pain, point tenderness, and cold sensitivity. Most glomus tumors will form well-circumscribed nodules, and excisional biopsy of masses detected by ultrasonography or magnetic resonance imaging of the lesion can relieve the symptoms. We describe a 30-year-old female patient with nontumorous glomus cell proliferation with clinical symptoms similar to those of glomus tumors. The lesion was treated by exploration and excision, with a satisfactory clinical outcome.

The association between meniscal subluxation and cartilage degeneration.

PURPOSE: The menisci play a critical protective role for the knee joint through shock absorption and load distribution. We hypothesized that cartilage degeneration will be abruptly progressed if meniscal subluxation exceeds a critical point. METHODS: Of 56 cases that showed medial meniscal subluxation without cartilage degeneration of ipsilateral medial femoral condyle (MFC) on initial MRI, from January 2005 to June 2007, meniscal subluxation index (MSI), the ratio of meniscal overhang to meniscal width in mid-coronal image of initial MRI, was measured. After 2 years, 40 cases were evaluated for cartilage degeneration of ipsilateral MFC on follow-up MRI. The relationship between medial MSI on initial MRI and cartilage degeneration of MFC on follow-up MRI was analyzed. Logistic regression analysis was conducted to find a critical point of meniscal subluxation related to cartilage degeneration. RESULTS: Abrupt progression of cartilage degeneration was observed from which MSI was 0.38. Logistic regression showed that if MSI was at the critical point, which was 0.38 in our study, then the probability of cartilage degeneration to grade 3 or 4 after 2 years was 44 %. If MSI was 0.4, then the probability was 50 %. If MSI was 0.6, then the probability was 99 %. CONCLUSIONS: The results suggest the existence of critical point from which the protective function of the meniscus appears to be significantly altered, and the degree of cartilage degeneration of ipsilateral femoral condyle corresponding to the amount of medial meniscal subluxation may be predictable.

Perioperative Risk Factors for Early Major Amputation Following First-Time Diabetic Forefoot Amputation.

BACKGROUND: Despite a meticulous multidisciplinary team approach, limb salvage remains uncertain even after the initial forefoot amputation in patients with end-stage diabetes. Which of many factors strongly influence the early failure of the limb salvage strategy remains unknown. This study aimed to analyze perioperative independent risk factors for major amputation within 1 year following first-time diabetic forefoot amputation. METHODS: Perioperative variables of 808 diabetic forefoot amputations performed in a tertiary referral center specialized for organ transplantation and end-stage diabetes were analyzed. Major amputations were performed in 104 patients (12.9%) throughout follow-up, and 77 (74%) of 104 patients had their major amputation within 1 year. Cox proportional hazards were examined to assess the risk factors for major amputation performed within 1 year. RESULTS: In univariate analysis, 18 possible risk factors significantly differed between patients with and without early major amputation. In stepwise multivariable analysis, chronic renal failure (CRF), peritoneal dialysis, and bilateral initial amputation were strong risk factors for early major amputation, with hazard ratios of 2.973 (95% CI 1.805-4.896, P < .0001), 2.558 (95% CI 1.113-5.881, P = .027), and 2.515 (95% CI 1.318-4.798, P = .005), respectively. CONCLUSION: Regardless of kidney transplantation (KT) status, CRF strongly predicts >20% chance of major amputation within 1 year after the first diabetic forefoot amputation.

Joint-Preserving Surgery for Hallux Valgus Deformity in Rheumatoid Arthritis.

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disorder that frequently causes forefoot deformities. Arthrodesis of the first metatarsophalangeal joint is a common surgery for severe hallux valgus. However, joint-preserving surgery can maintain the mobility of the joint. This study aimed to investigate the clinical and radiographic outcomes of distal chevron metatarsal osteotomy (DCMO) for correcting hallux valgus deformity associated with RA. Methods: Between August 2000 and December 2018, 18 consecutive patients with rheumatoid forefoot deformities (24 feet) underwent DCMO for hallux valgus with/without lesser toe surgery. Radiological evaluations were conducted, assessing the hallux valgus angle, the intermetatarsal angle between the first and second metatarsals, and the Sharp/van der Heijde score for erosion and joint space narrowing. Clinical outcomes were quantified using a visual analog scale for pain and the American Orthopaedic Foot and Ankle Society forefoot scores to measure function and alignment. Results: The mean hallux valgus angle decreased from 38.0° (range, 25°-65°) preoperatively to 3.5° (range, 0°-17°) at the final follow-up (p < 0.05). The mean intermetatarsal angle decreased from 14.9° (range, 5°-22°) preoperatively to 4.3° (range, 2°-11°) at the final follow-up. (p < 0.05). Regarding the Sharp/van der Heijde score, the mean erosion score (0-10) showed no significant change, decreasing from 3.83 (range, 0-6) preoperatively to 3.54 (range, 0-4) at the final follow-up (p = 0.12). Recurrent hallux valgus was observed in 1 patient and postoperative hallux varus deformity was observed in 2 feet. Spontaneous fusion of the metatarsophalangeal joint developed in 1 case. Conclusions: DCMO resulted in satisfactory clinical and radiographic outcomes for correcting RA-associated hallux valgus deformity.

Treatment of intractable septic ankle arthritis with a continuous closed irrigation system.

OBJECTIVES: The study aimed to evaluate the efficacy of a continuous closed irrigation system (CCIS) after open debridement for patients with intractable septic ankle arthritis. PATIENTS AND METHODS: The retrospective study analyzed the intractable septic arthritis of 12 (6 males, 6 females; mean age: 64.1±14.7 years; range, 33 to 80 years) patients managed by CCIS between July 2015 and July 2020. All patients had previously undergone operations to treat septic ankle arthritis without resolution of the infection. After open debridement, the CCIS was usually equipped with two outflow tubes and one inflow tube. Saline inflow was about 1 L per day. RESULTS: The mean follow-up period was 30.8±14.9 (range, 15 to 70) months. The CCIS was maintained for a mean of 5.1±2.1 (range, 3 to 7) days. The mean number of operations the patients had previously undergone was 2.83±1.5 (range, 1 to 6). For 11 (91.6%) out of 12 patients, infection did not recur after one-time CCIS, and laboratory test results remained normal. Six patients had previously undergone total ankle replacement arthroplasty. These patients underwent antibiotics-mixed cement arthroplasty after CCIS. For five of six with infected total ankle replacement arthroplasty, infection did not recur after CCIS. However, one patient without the removal of both implants experienced recurrence at the same site after four postoperative months. In the reoperation, after the removal of both implants and the application of antibiotics-mixed cement arthroplasty, the infection was cleared. CONCLUSION: Use of CCIS after open debridement for intractable septic ankle arthritis is a good treatment option since it is relatively simple and safe, with good results.

Comparison of open lateral release and transarticular lateral release in distal chevron metatarsal osteotomy for hallux valgus correction.

PURPOSE: The aim of this study was to investigate the difference in clinical and radiographic outcomes between conventional open lateral soft tissue release (OLSTR) and transarticular lateral soft tissue release (TLSTR) in patients undergoing distal chevron metatarsal osteotomy (DCMO) for hallux valgus (HV) correction. METHODS: This study included weight-bearing anteroposterior radiographs of 138 patients (185 feet) with HV that underwent DCMO and Akin phalangeal osteotomy at a mean age of 51.7 years (21-74) with a mean 26 months of follow-up between June 2004 and June 2010. Patients were classified into two groups: OLSTR as group 1 (84 feet) and TLSTR as group 2 (101 feet). We evaluated clinical and radiographic outcomes between the two groups using the American Orthopaedic Foot and Ankle Society hallux score, visual analogue scale pain score, hallux valgus angle, intermetatarsal angle and complications, pre- and post-operatively. RESULTS: There were no significant differences between the two groups except for post-operative complications such as first metatarsophalangeal joint (MTPJ) stiffness (group 1) and post-operative hallux varus (group 2). CONCLUSIONS: Clinical and radiographic outcomes between OLSTR and TLSTR in HV correction using DCMO were not significantly different except for post-operative limitation of motion of the first MTPJ and hallux varus tendency. Different precautions should be taken into account when choosing the type of lateral soft tissue release due to possible complications associated with each technique.

Pyoderma gangrenosum mimicking a diabetic foot infection: a case report.

An adult with ulcerative colitis and diabetes presented with a painful, swollen, edematous left foot. Diagnostic images and laboratory tests were inconclusive. Antibiotics were started immediately but aggravated his symptoms, and the laboratory results worsened. His foot was debrided twice per protocol for treating diabetic foot ulcers or cellulitis. After debridement, his condition worsened rapidly. Pyoderma gangrenosum was correctly diagnosed on the basis of massive neutrophilic infiltration detected in the biopsy tissue and because the lesion was well-defined and colored deep red to violet, unlike the bullosis diabeticorum blisters observed in the diabetic foot. His foot improved with systemic corticosteroids and topical wound care, and a skin defect was treated with a skin graft. After 9 months, his foot was well healed. Pyoderma gangrenosum can be diagnosed by careful examination and must be distinguished from an ulcerated diabetic foot lesion.

Excision with Temporary Interphalangeal Joint Pin Fixation for Toe Ganglion Cysts.

Background: Toe ganglion cysts are often symptomatic and recurrent. Communicating lesions between ganglion cysts and the interphalangeal joint (IPJ) or tendon sheath make it difficult to prevent a recurrence. Temporary restriction of the joint and tendon motion can facilitate surgical site healing. This study analyzed the clinical results of temporary pin fixation of the IPJ after toe ganglion cyst excision. Methods: Sixteen patients with symptomatic toe ganglion cysts underwent surgical treatment. Excision alone was initially performed on 10 patients. Six patients underwent temporary pin fixation of the IPJ after ganglion cyst excision. Repeat excision with pin fixation was performed for recurrence in two patients after excision only. Clinical evaluations and postoperative complications were analyzed. Results: Fourteen of 16 toe ganglion cysts were located near the IPJ. Two cysts not adjacent to the joint completely healed after excision alone. Seven of 14 cysts near the joint recurred after initial excision alone and required repeated reoperation. Eight cysts did not recur after excision with pin fixation, including 2 that recurred after excision alone. Conclusions: Temporary IPJ pin fixation after excision for ganglion cysts can be effective for preventing the recurrence of ganglion cysts adjacent to toe IPJ.

Long Hallucal Tendon Force Vectors and First Metatarsophalangeal Deformity After Hallux Valgus Surgery.

BACKGROUND: Recurrence is one of the most common complications following hallux valgus surgery. Moreover, hallux varus occurs in cases of overcorrection. We aimed to quantitatively measure, using radiographic examination, the dynamics of the soft tissues that act on deformities (recurrence of valgus and occurrence of varus) after the surgery. METHODS: This retrospective single-institution study included 60 patients (98 feet) who underwent hallux valgus surgery between 2009 and 2018. According to radiographic findings of the foot under weightbearing conditions at postoperative month 1, we examined the tendons' pathway and calculated the forces on the first metatarsophalangeal joint, which we termed the deformity force angle (DFA). We compared whether there was a significant difference in DFAs between the groups in which deformities occurred and those in which deformities did not occur after correction. In addition, the DFA was compared to known radiographic measurements of hallux valgus recurrence (hallux valgus angle, distal metatarsal articular angle, intermetatarsal angle, and sesamoid position) to assess association with recurrence. RESULTS: We observed a significant difference in the DFA between patients with and without hallux valgus recurrence (P < .001) and between those with and without hallux varus (P < .001) based on standing radiographs taken at a minimum of 6 months postoperation. For predicting the deformities, the areas under the curve were 0.863 (hallux valgus recurrence) and 0.831 (hallux varus occurrence), respectively, which was greater than other factors evaluated. The DFA values greater than 9.5 degrees and less than 5.5 degrees were associated with the recurrence of valgus and occurrence of varus, respectively. CONCLUSION: In our study, DFA was associated with hallux valgus recurrence when it exceeded 9.5 degrees and hallux varus when it was less than 5.5 degrees. Moreover, in the hallux valgus surgery we performed, a DFA from 5.5 to 9.5 degrees appeared to be a "safe zone" for preventing early deformity after surgery. LEVEL OF EVIDENCE: Level III, prognostic.

Relationship Between Hallux Valgus Recurrence and Sesamoid Position on Anteroposterior Standing Radiographs After Distal Chevron Metatarsal Osteotomy.

BACKGROUND: Recurrence of the hallux valgus deformity has various causes, and the incomplete reduction of sesamoids may be one of the important issues. However, we have seen several patients with postoperative lateral sesamoid displacement on anteroposterior (AP) standing radiographs who did not experience hallux valgus recurrence. Therefore, we hypothesized that lateral displacement of the sesamoid on AP standing radiographs does not cause hallux valgus recurrence. METHODS: The study included 269 feet (185 patients) with hallux valgus treated with distal chevron metatarsal osteotomy. Mean patient age was 64.26 (range, 15-80) years. Patients were followed up for an average of 33.85 (range, 12-228) months between April 2002 and December 2019. The patients were divided into 4 groups, according to the presence or absence of hallux valgus recurrence and sesamoid reduction. RESULTS: During outpatient follow-up, we discovered 99 feet (42.1%) in which hallux valgus did not recur despite lateral sesamoid displacement (grade IV-VII) on AP standing radiographs. Hallux valgus angle (HVA, 2.7 to 7.9 degrees), intermetatarsal angle (IMA, 4.6 to 6.2 degrees), and sesamoid grades (2.1 to 3.5) all deteriorated over time after surgery, and each indicator was statistically significantly altered, and changes in the 3 indicators had a statistically significant positive correlation. Changes in HVA and IMA between feet with and without sesamoid reduction on AP standing radiographs increased over time, with the differences in HVA (2.9 degrees) and IMA (0.9 degrees) being significant at final follow-up (P < .05 for each). Regardless of whether sesamoid reduction was achieved on AP standing radiographs, the final analysis showed that HVA and IMA in both groups worsened over time. Further, there were no differences between the 2 groups in the patterns of change over time. CONCLUSION: In our cohort, postoperative sesamoid position on AP standing radiographs was not associated with hallux valgus recurrence based on radiographic criteria. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Factors influencing successful bone union of isolated subtalar arthrodesis for posttraumatic subtalar arthritis: a multicenter case series.

BACKGROUND: The purpose of this study was to find the factors influencing successful bone union for isolated subtalar arthrodesis in posttraumatic subtalar arthritis following calcaneal fracture. MATERIAL AND METHODS: We retrospectively analyzed the rate of successful bone union of 119 cases of isolated subtalar arthrodesis for posttraumatic subtalar arthritis performed at five university hospitals between January 2010 and December 2019. Multivariate logistic regression analysis was used to find the factors associated with successful bone union. Successful bone union was defined as resolution of hindfoot pain with the presence of osseous trabecular bridging involving more than 50% of the posterior facet within 6 months postoperatively. RESULTS: There were 77 (64.7%) cases of successful bone union, 11 (9.2%) cases of delayed union, 8 (6.7%) cases of questionable union, and 23 (19.3%) cases of nonunion. Use of fully threaded screws was 5.90 times [odds ratio (OR) = 5.90, 95% confidence interval (CI) = 1.42-24.49, p = 0.02] more likely to achieve successful bone union compared to the use of partially threaded screws. Use of two parallel screws or the two divergent screws were 3.71 times (OR = 3.71, 95% CI = 1.05-13.14, p = 0.04) and 4.65 times (OR = 4.65, 95% CI = 1.23-17.53, p = 0.02) more likely to achieve successful bone union compared to the use of a single screw. Use of cancellous autograft or structural autograft was 4.72 times (OR = 4.72, 95% CI = 1.17-19.06, p = 0.03) and 7.12 times (OR = 7.12, 95% CI = 1.46-34.68, p = 0.02) more likely to achieve successful bone union compared to no graft use. CONCLUSION: Use of fully threaded screws, autograft, and two screws compared to a single screw were the factors associated with successful bone union within six postoperative months after subtalar arthrodesis for the posttraumatic arthritis.

Surgical treatment of non-diabetic chronic osteomyelitis involving the foot and ankle.

BACKGROUND: We evaluated the clinical characteristics and treatment outcomes of patients with chronic osteomyelitis in the foot and ankle in patients without diabetes. METHODS: We reviewed 15 patients treated for chronic osteomyelitis involving the foot and ankle between September 2004 and March 2007. Patients with diabetes mellitus or who were immunocompromised were excluded. The cause of osteomyelitis, sites of occurrence, causative pathogens, and invasion of the adjacent joint(s) were reviewed, then the clinical characteristics were analyzed. Magnetic resonance imaging was performed to clarify the extent of infection and invasion of the adjacent joint. Surgical management included wide debridement, dead space control, and arthrodesis if there was invasion of the adjacent joint. The mean postoperative followup period was 3.3 years, during which recurrences and complications were evaluated. RESULTS: Extrinsic causes accounted for 86.7% of the chronic osteomyelitis involving the foot and ankle. The most common cause of osteomyelitis was trauma with ten cases due to complications following fractures or dislocation. Methicillin-resistant Staphylococcus aureus and Pseudomonas were the most common causative pathogens. In 46.7% of the patients, the adjacent joint was involved and an arthrodesis was performed. The mean length of the hospital stay was 39.1 days. The average of number of surgeries was two. Fourteen of 15 patients had no recurrence. CONCLUSION: For the successful treatment of chronic osteomyelitis involving the foot and ankle, an arthrodesis based on invasion of the adjacent joint as well as wide debridement and dead space control was successful in this series.

Hallux valgus correction using transarticular lateral release with distal chevron osteotomy.

BACKGROUND: Transarticular lateral release through a medial incision can avoid a dorsal incision. This study investigated outcomes following hallux valgus correction using transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision. METHODS: Between June 2004 and May 2009, a single surgeon performed a transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision for hallux valgus on a total of 103 feet of 68 patients. The average patient age at the time of surgery was 51 years, and the average followup was 27 months. RESULTS: The average preoperative and final followup results were: 1) hallux valgus angle improvement from 29 degrees to 5 degrees, 2) intermetatarsal angle from 13 degrees to 5 degrees and 3) medial sesamoid bone position from 3 to 1 (p < 0.05 for each variable). The average AOFAS scores were improved from 49 to 92, and the VAS pain scores were improved from 7 to 1 (p < 0.05 for both variables). No patient had a serious complication such as infection, avascular necrosis, nonunion, transfer-metatarsalgia, or first metatarsophalangeal joint arthritis. CONCLUSION: Hallux valgus correction using transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision was found to be effective and safe. The advantages include that the procedure is simple, early ambulation is possible, and there is no dorsal scarring.

Contribution Ratio of Metatarsal Osteotomy and First Tarsometatarsal Joint Reduction in Moderate to Severe Hallux Valgus Correction.

Hallux valgus is a common foot and ankle disease, for which numerous surgical procedures were introduced. So, understanding the mechanism of deformity reduction is important to select the proper method. Intermetatarsal angle (IMA) determines the severity of hallux valgus, which is influenced by the translated metatarsal head and the reduction of the first tarsometatarsal joint. We hypothesized that both of the mechanisms simultaneously contribute to the correction of IMA. Hallux valgus (70 feet) operated with a Scarf osteotomy with the Akin procedure were reviewed. Hallux valgus angle (HVA), IMA (mechanical and anatomical), hallux valgus interphalangeal angle (HVIP), distal metatarsal articular angle (DMAA), and sesamoid position were checked. The ratio of contributions to the IMA changes were calculated and compared. When the individual contributions by metatarsal head translation and first tarsometatarsal joint reduction were compared, metatarsal head translation contributed by 82%, whereas first tarsometatarsal joint reduction contributed by 18%. Both were responsible for mechanical IMA correction. However, IMA change by metatarsal head translation was a major correction mechanism compared to anatomical IMA change by first tarsometatarsal joint reduction.