Yeokgu Hwang

Short-term Clinical and Radiographic Results of the Salto Mobile Total Ankle Prosthesis:

Background: The mobile-bearing Salto total ankle prosthesis has been reported to have promising outcomes. However, clinical reports on this prosthesis are few, and most have been published by the inventors and disclosed consultants. Methods: We retrospectively reviewed 59 patients who received Salto prosthesis unilaterally. The average follow-up was 35.9 (range, 6-56) months. Clinical and radiologic results were evaluated. Clinical results were evaluated according to visual analog scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Ankle Osteoarthritis Scale (AOS) pain and disability score, and ankle range of motion (ROM) in dorsiflexion/plantarflexion. In the radiographic evaluation, we measured the tibial angle (TA), talar angle (TAL), tibial slope, and talocalcaneal angle (TCA) on weightbearing radiographs. Results: By the last follow-up, 7 of 59 patients (11.9%) had undergone reoperation, and 3 of 59 implants (5.1%) had been removed. The prosthesis survival was 94.9% (95% CI, 89.1%-100%). With any reoperation as the endpoint of follow-up, the clinical success rate was 88.1% (95% CI, 79.4%-96.9%). The mean postoperative visual analog scale score, AOFAS ankle-hindfoot score, and Ankle Osteoarthritis Scale pain and disability score improved significantly (P < .001). The ankle range of motion also improved from preoperative 33.4 ± 16.6 to 40.3 ± 15.5 postoperatively (P < .001); however, there was no statistically significant change in plantarflexion (P = .243). Radiolucent areas and osteolysis were found in 28 (47.5%) and 27 (45.8%) patients, respectively. Heterotopic ossification was observed in 13 patients (22.0%). Conclusions: In this series, early clinical and radiographic outcomes of this prosthesis were promising. We believe the early radiolucent lines were probably due to the gap at the implant and bone interface, and they disappeared at the time of osseous integration. However, longer follow-up is necessary to determine the long-term durability and survivorship of this implant, particularly given the high incidence of postoperative osteolysis. Level of Evidence: Level IV, case series.

Long-term evaluation of Primary Osteochondral Autograft Transfer System (OATS) for large cystic type osteochondral lesion of talus

Category: Ankle Introduction/Purpose: Osteochondral lesions of talus (OLTs) are often treated primarily by fragment excision, abrasion, drilling, or microfracture. However, OLT accompanying with large cyst has been challenged to yield good outcome nevertheless of many surgical options. Recent study showed significant high failure rate of arthroscopic marrow stimulation treatment larger than 150mm2. The current study is to investigate the outcome of the primary osteochondral autograft transfer system (OATS) for large cystic type OLT (>150mm2). Methods: This retrospective analysis included 19 talus (19 patients) with diagnosed large cystic type OLT (>150mm2) who received primary OATS between September 2009 and March 2013. Defect size area was measured on magnetic resonance imaging (MRI) by the ellipse formula from coronal and sagittal length. The patients completed the visual analog scale (VAS) and the American Orthopaedic Foot & Ankle Society (AOFAS) score preoperatively and at follow-up. Plain radiographs were used to show the improvement of radiolucency postoperatively. Results: The mean follow up period was 83.9 months (57 – 99) and the average defect size area was 169.4 mm2 (151.3 – 392.6). The Mean VAS score decreased from 6.95 preoperatively to 2.6 postoperatively. Average AOFAS score improved from 66.8 preoperatively to 88.7 postoperatively. Eighty percent of patients rated their result excellent or good. The radiolucent area of the cysts disappeared on the plain radiographs in all cases. Conclusion: Long-term clinical results of primary OATS in large cystic type OLT showed good outcomes and patients could significantly benefit from this surgery.

Primary Versus Secondary Osteochondral Autograft Transplantation for the Treatment of Large Osteochondral Lesions of the Talus

Background: Recent studies have reported promising clinical results after osteochondral autograft transplantation (OAT) for the treatment of large osteochondral lesions of the talus (OLT). However, no study has yet compared clinical outcomes between primary and secondary OAT for large OLT. Purpose: To compare clinical outcomes among patients with large OLT who receive primary OAT versus those who receive secondary OAT after failure of marrow stimulation and to identify factors associated with clinical failure. Study Design: Cohort study; Level of evidence, 3. Methods: From 2005 to 2014, 46 patients with large OLT (≥150 mm2) underwent OAT: 18 underwent OAT as initial surgical management (primary OAT group), and 28 patients underwent secondary OAT after failure of previous arthroscopic marrow stimulation (secondary OAT group). In both groups, OAT procedures included arthroscopic inspection and debridement of concomitant soft tissue injuries. Clinical outcomes were assessed using pain visual analog scale (VAS), the Roles and Maudsley score, Foot and Ankle Outcome Scores (FAOS), and revisional surgery rates. Factors associated with clinical failures were evaluated using bivariate and logistic regression analyses. Survival outcomes were compared using Kaplan-Meier analysis. Results: Mean follow-up time was 6 years (range, 2-10.8 years). Mean lesion size was 194.9 mm2 (range, 151.7-296.3 mm2). There were no significant differences between groups in patient demographics and preoperative findings. Postoperative pain VAS, Roles and Maudsley score, FAOS, and revisional surgery rates were not significantly different at last follow-up. Prior marrow stimulation was not significantly associated with clinical failure on bivariate analysis. Lesion size greater than 225 mm2 on preoperative magnetic resonance imaging was significantly associated with clinical failure. Survival probabilities from Kaplan-Meier plots were not significantly different between the primary and secondary OAT groups (P = .947). Conclusion: Clinical outcomes of patients with large OLT treated with secondary OAT after failed marrow stimulation were found to be comparable with those who were treated with primary OAT. These results may be helpful to orthopaedic surgeons deciding appropriate surgical options for patients with large OLT.

Clinical Efficacy of a Kaolin-impregnated Dressing for Hemostatic Control in Diabetic Foot Ulcer Patients Receiving Anticoagulant Therapy in an Outpatient Clinic: Prospective, Randomized, Clinical Trial

Category: Diabetes Introduction/Purpose: Orthopedic physicians encounter many diabetes patients who receive anticoagulant treatment because vascular diseases are the chief causes of death and disability in these patients. In these patients, if surgery or other procedures are required, it is still unclear whether anticoagulation therapy administration should continue. After discontinuation of anticoagulation therapy, the risk of cardiovascular complications is increased, although complications of bleeding after surgery are decreased; this is a dilemma in the treatment of diabetic foot ulcer. The purpose of this study was to examine the effectiveness, safety, and hemostatic effect of kaolin-impregnated gauze on diabetic foot ulcer patients who continue to receive anticoagulants after surgical debridement. Methods: Twenty patients receiving anticoagulant medication with diabetic foot ulcers requiring surgical debridement were enrolled. Diabetic foot ulcers were treated using surgical debridement and a basic dressing protocol, which involved direct application of the dressing material to the wound bed. For the study group, a kaolin-impregnated dressing was used, and dry gauze was applied to patients in the control group. Patients were randomly assigned to either group, and we compared hemostatic efficacy and adverse effects between the two groups. The presence or absence of hemostasis was assessed 5 and 10 minutes after dressing application. Treatment was considered successful if bleeding ceased adequately and no extra hemostatic measures were required within 10 minutes. Results: In the 20 patients undergoing surgical debridement, there was no evidence of bleeding within 10 minutes of dressing application. Eight of the 10 patients treated with a kaolin-impregnated dressing achieved complete hemostasis within 5 minutes. Five of the 10 patients in the control group failed to achieve hemostasis within 10 minutes. No adverse effects were noted. Conclusion: The use of a kaolin-impregnated dressing appears to be a safe, feasible, and beneficial option for the management of diabetic foot ulcer patients with a high risk of bleeding.

Can Generalized Ligamentous Laxity be an Obstacle to Perform Minimally Invasive Surgery for Moderate Hallux Valgus

Category: Bunion Introduction/Purpose: Minimally invasive surgical techniques have challenged objectives in hallux valgus surgery, attempting to obtain good clinical outcomes with the least damage to anatomic structures, low complication rates, short time of surgery, cosmetic advantages and an earlier recovery. However, because patients with generalized ligamentous laxity have a major risk for recurrence, arthrodesis of the first tarsometatarsal (TMT) joint is an established method for the surgical treatment of the patients with generalized ligamentous laxity. This study aims to investigate the clinical and radiographic outcomes of joint-preserving minimally invasive distal metatarsal osteotomy in moderate hallux valgus patients with generalized ligamentous laxity. Methods: Thirty-two feet from 29 patients were involved prospectively with mean follow-up of 16.8 (range, 10 – 26) months. Generalized ligamentous laxity was assessed in all patients and the patients were divided into two groups (16: 16) with the result. Clinical outcomes were assessed using visual analogue scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) score and Foot and Ankle Outcome Score (FAOS). Radiographic parameters were evaluated by preoperative and postoperative weight bearing radiographs. Results: Mean tourniquet time was 30.4 (range, 19 – 44) minute and additional procedures were required in 6 cases in each group. The mean VAS (p<0.001), AOFAS score (p<0.001) and three FAOS subscales (Pain, Symptoms and Quality-of-Life) (p=0.003, p=0.002 and p<0.001) improved significantly at the last follow-up. Significant corrections in the hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA) and sesamoid reduction were obtained at the last follow-up (p<0.001). Relative first metatarsal length was decreased 2.8% from preoperative length (p<0.001). No other radiographic outcomes showed significant difference between the 2 groups but the mean relative first metatarsal length was shorter in the group without generalized ligamentous laxity (p=0.014, respectively) at the last follow-up. Conclusion: Despite the patients without generalized ligamentous laxity tended to have shorter first metatarsal bone postoperatively, minimally invasive distal metatarsal osteotomy yielded substantial clinical and radiological results without any recurrence or fixation failure. This procedure can be a reasonable alternative to first TMT arthrodesis in patients with moderate hallux valgus even with generalized ligamentous laxity.

Detection of Tram Track Lesion in the Ankle Joint; A Comparative Study of Magnetic Resonance Imaging with Ankle Arthroscopy

Category: Ankle, Arthroscopy Introduction/Purpose: Tram track lesion in the ankle joint has been occasionally found during the ankle arthroscopy and there has been few studies relating the pathophysiology, diagnostic method and treatment of the lesion. This study aimed to show the effectiveness of magnetic resonance imaging (MRI) for detection of tram track lesion in the ankle joint comparing with ankle arthroscopy. Methods: We retrospectively assessed 175 ankles in 170 patients with anterior bony impingement syndrome in the ankle who underwent arthroscopic surgery between January 2013 and July 2015. Anterior ankle bony spurs were scored in preoperative weight-bearing radiographs using the impingement classification. MRIs were reviewed for the detection of tram track lesions according to our definition (focal high signal intensity along the talar dome cartilage surface on coronal view), which were then compared with arthroscopic findings. The grade of cartilage defect was stratified according to international cartilage repair society (ICRS) grading system by arthroscopic finding. Results: Fourteen (8.0%) ankles were identified with tram track lesion on MRI and 16 (9.1%) ankles were identified with tram track lesion at ankle arthroscopy. Overall sensitivity of MRI for detection of tram track lesion was 87.5% and specificity was 100%. On plane weight-bearing radiographs, 4 patients had grade 1, 2 patients had grade 2 and 10 patients had grade 3 impingement spurs. Under the ICRS grading system, 4 cases were grade 2, 4 cases were grade 3, and 8 cases were grade 4 at arthroscopy. Comparing with MRI, 2 cases of grade 2, 4 cases of grade 3 and 8 cases of grade 4 were detected (Table). Impingement spur grade showed no significant correlation with arthroscopic ICRS grade of tram track lesion (p = 0.609). Conclusion: Tram track lesions in the ankle joint can be confidently detected on MRI with high sensitivity and specificity. Early detection and following treatment of the lesion can maximize the clinical outcome that eliminates the possibility for further damage to the cartilage and consequent osteoarthritic change.

Effectiveness of hyaluronic acid injection after failed arthroscopic microfracture in osteochondral lesion of the talus

Category: Ankle, Arthroscopy Introduction/Purpose: Non-operative treatment options with symptomatic OLT after failed primary arthroscopic treatment may be treated by various methods such as analgesics, anti-inflammatory drug, steroid injection, Platelet rich plasma (PRP) injection and hyaluronic acid (HA) injection. HA injection could be treated OLT besides osteoarthritis on knee or ankle joint. Effect of HA is viscoelastic and lubricating properties primarily, and other biomechanical effect can be considered. Purpose of this study is to evaluate the clinical outcomes of intra-articular HA injection in the patients with recurrent pain after the arthroscopic microfracture for OLT Methods: This study included 20 patients who received three weekly injections of intra-articular HA after arthroscopic microfracture for OLT between June 2014 and August 2016. All patients had persistent pain for more than 3 months after the index surgery. The patients were followed for 16.7 months (range: 4.6-30.9). At each visit, the efficacy of HA injection in reducing pain was evaluated by a Visual Analog Scale (VAS). In addition, subjective satisfactions were assessed by the Alexander scale. Results: The mean period from the arthroscopic microfracture to the intra-articular HA injection was 26.5 months (range: 6.0- 87.0). Mean VAS scores decreased from 6.7 ± 1.1 at a pre-injection to 3.8 ± 2.3 at post-injection six months (p = 0.02). According to the Alexander scale, there were 65.0% (13/20) good, 25.0% (5/20) fair, and 10.0% (2/20) poor results at post-injection six months. There was no severe adverse effect. Conclusion: The HA injection may be a useful treatment option after failed arthroscopic microfracture in OLT. Further studies will be needed to evaluate long-term results.

The Fate of Bone Graft for Periprosthetic Osteolysis in Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: Periprosthetic osteolysis in total ankle arthroplasty (TAA) is a substantial problem. It may cause implant failure and has potential to affect long-term implant survival. To prevent major revisional arthroplasty, it is important to make an early diagnosis of osteolysis and decide an appropriate timing of surgical intervention such as bone graft. We report our experience of bone graft for osteolysis after TAA associated with clinical and radiologic outcome. Methods: Between May 2004 and Oct. 2013, 238 primary TAA were performed on 219 patients. We excluded 37 ankles with follow-up less than 24 months; thus, 201 ankles in 185 patients with mean follow-up of 61.9 (range, 24-130) months were included in the study. Nineteen patients were treated with a total of 21 bone graft procedures for periprosthetic osteolysis after TAA. Of these patients, 12 (57.1%) were males with mean follow-up length after bone graft 35.0 months. Location of osteolysis, bone grafting method and clinical outcome parameters using visual analog scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) score were recorded. Results: Radiographs revealed total of 62 osteolysis lesions in 19 patients; 35 (56.5%) distal tibial lesions, 23 (37.0%) talar lesions. Autogenous iliac bone graft was used in 18 procedures (85.7%). The mean scores (and standard deviation) improved for the VAS from 4.8 ± 1.23 points before bone graft to 3.0 ± 0.94 points at the last follow-up (p<0.05); and for the AOFAS score from 76.8 ± 5.9 before bone graft to 84.3 ± 4.5 at the last follow-up (p<0.05). After 21 bone graft procedures, 6 demonstrated detection of newly developed osteolysis. One patient needed a repeat bone graft procedure with cementation after the primary bone grafting due to large cyst on distal tibia. There was no implant failure or major revisions after the bone graft. Conclusion: Bone graft for periprosthetic osteolysis may improve patient’s clinical outcome and give support to the structures surrounding the implant. Bone grafting in optimal timing may also improve implant survivorship. However, further study is needed for the etiology of newly developed painless osteolysis even after the bone graft.

Collagen Dressing in the Treatment of Diabetic Foot Ulcer A Prospective, Randomized, Placebo- Controlled, Single-Center Study

Category: Diabetes Introduction/Purpose: Ulcer healing in the diabetic patients is challenging due to a prolonged inflammatory response, extracellular matrix degradation irregularities, and increased bacteria presence. Collagen components are fundamental to the process of wound healing and skin formation. Recently, collagen-containing wound dressings, which create a biological scaffold matrix, have been used in the treatment of diabetic foot ulcer (DFU). However, there is not enough evidence to support that 100% collagen dressing can replace the diabetic wound management. In this study, we examined the effectiveness and safety of a new collagen dressing material in the treatment of DFU. Methods: This study was a prospective, randomized, placebo-controlled, single-center study conducted between November 2011 and September 2014. The inclusion criteria were type 1 or 2 diabetes, a ulcer size ≥ 1.0 cm2 that did not exhibit signs of healing for 6 weeks, Wagner grade 1 or 2, and palpable pulses at the ankle. The assessments of DFU included size, microbial culture study, detailed description of DFU, and clinical photos. Patients in the study group were treated with a collagen dressing material (100% porcine type I collagen) and foam dressing, while patients in the control group were treated with only foam dressing. Dressing changes had been performed two or three times per week. Complete ulcer healing rate was evaluated as a primary endpoint and ulcer size were compared between the two groups as a secondary endpoint. Results: Thirty patients were included in the final analysis (study group: 17 patients, control group: 13 patients). There were no significant differences between two groups regarding demographic factors and baseline DFU characteristics. The study group presented a higher rate of complete healing as compared to that in the control group [82.4% (14/17), 38.5% (5/13), respectively, P = 0.022]. At the last follow-up, ulcer sizes of the study group were smaller than those of the control group (P = 0.048). The Kaplan-Meier analysis for the complete ulcer healing also showed a significantly higher rate of complete healing in the study group (Hazard ratio = 3.0, log-rank P = 0.025). There were no adverse events related to the dressing materials. Conclusion: This study supports that the wound dressing using 100% collagen materials may offer a safe and effective treatment for DFU.

Hyaluronic Acid Dressing in the Treatment of Diabetic Foot Ulcer A Prospective, Randomized, Placebo-Controlled, Single-Center Study

Category: Diabetes Introduction/Purpose: Fast and complete healing of a diabetic foot ulcer (DFU) is challenging due to the hostile wound healing environment of the diabetic patients. As a part of a multimodal treatment approach, advanced dressing material using hyaluronic acid (HA) has been found to be effective. However, previous studies have used HA with additional biologics, which interferes in determining the true clinical effect of HA in DFU. The purpose of this study is to examine the effectiveness and safety of a new HA dressing material in the treatment of DFU. Methods: This study was a prospective, randomized, placebo-controlled, single-center study conducted between September 2012 and January 2014. The inclusion criteria were type 1 or 2 diabetes, a ulcer size ≥ 1.0 cm2 that did not exhibit signs of healing for 6 weeks, Wagner grade 1 or 2, and palpable pulses at the ankle. The assessments of DFU included size, microbial culture study, detailed description of the DFU, and clinical photos. Patients in the study group were treated with an HA dressing material (hyaluronic acid 80 ± 5% and poloxamer 10 ± 5%), while patients in the control group were treated with a conventional moisture- retentive dressing (petrolatum gauze). Weekly follow-up was conducted with the dressing change up to maximum 12 weeks. Complete ulcer healing rate was evaluated as a primary endpoint. Additionally, healing velocity and the mean duration for achieving a 50% ulcer size reduction was compared between the two groups as a secondary endpoint. Results: Twenty-five patients were included in the final analysis (study group: 13, control group: 12). There were no significant differences between two groups regarding demographic factors and baseline DFU characteristics. The study group presented a significantly higher complete healing rate as compared to that in the control group [84.6% (11/13), 41.6% (5/12), respectively, P = 0.041]. Faster ulcer healing velocity and shorter mean duration for achieving a 50% ulcer size reduction were observed in the study group (P = 0.022, P = 0.004, respectively). The Kaplan-Meier analysis for the median time for 50% ulcer healing rate also showed a significantly shorter duration in the study group (21 days vs 39 days, P = 0.012). There were no adverse events related to the dressing materials. Conclusion: This study supports that a HA dressing without additional substances may offer a safe and effective treatment for DFU.