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.

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.

Effect of neck flexor muscle activation on impact velocity of the head during backward falls in young adults

Falls are a common cause of traumatic brain injuries (TBI) across the lifespan. A proposed but untested hypothesis is that neck muscle activation influences impact severity and risk for TBI during a fall. We conducted backward falling experiments to test whether activation of the neck flexor muscles facilitates the avoidance of head impact, and reduces impact velocity if the head contacts the ground. Young adults (n=8) fell from standing onto a 30cm thick gymnastics mat while wearing a helmet. Participants were instructed to fall backward and (a) prevent their head from impacting the mat ("no head impact" trials); (b) allow their head to impact the mat, but with minimal impact severity ("soft impact" trials); and (c) allow their head to impact the mat, while inhibiting efforts to reduce impact severity ("hard impact" trials). Trial type associated with peak magnitude of electromyographic activity of the sternocleidomastoid (SCM) muscles (p<0.017), and with the vertical and horizontal velocity of the head at impact (p<0.001). Peak SCM activations, expressed as percent maximal voluntary isometric contraction (%MVIC), averaged 75.3, 67.5, and 44.5%MVIC in "no head impact", "soft impact", and "hard impact" trials, respectively. When compared to "soft impact" trials, vertical impact velocities in "hard impact" trials averaged 87% greater (3.23 versus 1.73m/s) and horizontal velocities averaged 83% greater (2.74 versus 1.50m/s). For every 10% increase in SCM %MVIC, vertical impact velocity decreased 0.24m/s and horizontal velocity decreased 0.22m/s. We conclude that SCM activation contributes to the prevention and modulation of head impact severity during backward falls.

Lesion Size Is a Predictor of Clinical Outcomes After Bone Marrow Stimulation for Osteochondral Lesions of the Talus: A Systematic Review

BACKGROUND

The critical lesion size treated with bone marrow stimulation (BMS) for osteochondral lesions of the talus (OLTs) has been 150 mm² in area or 15 mm in diameter. However, recent investigations have failed to detect a significant correlation between the lesion size and clinical outcomes after BMS for OLTs.

PURPOSE

To systematically review clinical studies reporting both the lesion size and clinical outcomes after BMS for OLTs.

STUDY DESIGN

Systematic review.

METHODS

A systematic search of the MEDLINE and EMBASE databases was performed in March 2015 based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included studies were evaluated with regard to the level of evidence (LOE), quality of evidence (QOE), lesion size, and clinical outcomes.

RESULTS

Twenty-five studies with 1868 ankles were included; 88% were either LOE 3 or 4, and 96% did not have good QOE. The mean area was 103.8 ± 10.2 mm² in 20 studies, and the mean diameter was 10.0 ± 3.2 mm in 5 studies. The mean American Orthopaedic Foot and Ankle Society score improved from 62.4 ± 7.9 preoperatively to 83.9 ± 9.2 at a mean 54.1-month follow-up in 14 studies reporting both preoperative and postoperative scores with a mean follow-up of more than 2 years. A significant correlation was found in 3 studies, with a mean lesion area of 107.4 ± 10.4 mm², while none was reported in 8 studies, with a mean lesion area of 85.3 ± 9.2 mm². The lesion diameter significantly correlated with clinical outcomes in 2 studies (mean diameter, 10.2 ± 3.2 mm), whereas none was found in 2 studies (mean diameter, 8.8 ± 0.0 mm). However, the reported lesion size measurement method and evaluation method of clinical outcomes widely varied among the studies.

CONCLUSION

An assessment of the currently available data does suggest that BMS may best be reserved for OLT sizes less than 107.4 mm² in area and/or 10.2 mm in diameter. Future development in legitimate prognostic size guidelines based on high-quality evidence that correlate with outcomes will surely provide patients with the best potential for successful long-term outcomes.

Fluorocarbon Thin Films Fabricated using Carbon Nanotube/Polytetrafluoroethylene Composite Polymer Targets via Mid-Frequency Sputtering

Carbon nanotube/polytetrafluoroethylene composite polymer targets are proposed for use in the fabrication of fluorocarbon thin films using the mid-frequency sputtering process. Fluorocarbon thin films deposited using carbon nanotube/polytetrafluoroethylene composite targets exhibit an amorphous phase with a smooth surface and show a high water contact angle, optical transmittance, and surface hardness. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy studies reveal that as the carbon nanotube concentration increased in the composite target, a carbon cross-linked structure was formed, which enhanced the film hardness and the modulus of the fluorocarbon thin film. Large-area fluorocarbon thin films with a substrate width of 700 mm were successfully fabricated by a pilot-scale roll-to-roll sputtering system using a carbon nanotube/polytetrafluoroethylene composite target.

Inhibition of microRNA-449a prevents IL-1β-induced cartilage destruction via SIRT1

OBJECTIVE

SIRT1 has anti-inflammatory as well as protective effects in chondrocytes. The object of this study was to investigate whether microRNA-449a regulates expression of SIRT1, which inhibits expression of catabolic genes in IL-1β-induced cartilage destruction.

MATERIALS AND METHODS

MicroRNA-449a expression was determined in OA chondrocytes and IL-1β-induced chondrocytes by real-time PCR. MicroRNA-449a binding sites on the 3'-UTR of SIRT1 mRNA and binding site conservation were examined using microRNA target prediction tools. SIRT1-overexpressing or knockdown chondrocytes were transfected with microRNA-449a or anti-microRNA-449a mimic and stimulated by IL-1β. Expression of catabolic and anabolic genes was examined by real-time PCR and western blotting. Finally, positive effects of anti-microRNA-449a on expression of these genes were confirmed by western analysis of OA chondrocytes.

RESULTS

Expression of microRNA-449a was increased in OA chondrocytes and IL-1β-induced chondrocytes. MMP-13 expression was enhanced, whereas type II collagen and SIRT1 expression were decreased in IL-1β-induced chondrocytes. SIRT1 overexpression resulted in decreased expression of catabolic genes such as MMPs and ADAMTSs in response to IL-1β, but these effects were moderated by microRNA-449a. Suppression of microRNA-449a by anti-microRNA-449a inhibited expression of catabolic genes despite IL-1β stimulation, but these effects were abolished in SIRT1 knockdown chondrocytes. Furthermore, expression of catabolic genes was decreased and expression of type II collagen as well as SIRT1 was restored by anti-microRNA-449a in OA chondrocytes as well as in IL-1β-induced chondrocytes.

CONCLUSION

Silencing of microRNA-449a had a protective effect, inhibiting catabolic gene expression and restoring anabolic gene expression, by targeting SIRT1 in IL-1β-induced cartilage destruction.

Mucus-Penetrating Nanosuspensions for Enhanced Delivery of Poorly Soluble Drugs to Mucosal Surfaces

Mucus-penetrating nanosuspensions, consisting of pure hydrophobic therapeutics with dense muco-inert coatings that enable particles to effectively bypass the mucus barrier, demonstrate superior drug distribution and absorption at mucosal surfaces. With significantly increased drug load compared to polymeric systems and established clinical translation of nanosuspensions-based products, mucus-penetrating nanosuspensions are a promising vehicle for improving mucosal delivery of poorly soluble drugs.

Generalized Ligamentous Laxity Is an Independent Predictor of Poor Outcomes After the Modified Broström Procedure for Chronic Lateral Ankle Instability

BACKGROUND

The modified Broström procedure for chronic lateral ankle instability (CLAI) has presented outstanding clinical results. However, after the procedure, some patients with generalized ligamentous laxity have experienced a recurrence of ankle instability.

PURPOSE

To understand the effect of generalized ligamentous laxity on prognosis and risk of recurrence in a cohort of patients with CLAI after the modified Broström procedure.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 199 ankles from 188 patients underwent the modified Broström procedure for CLAI with a mean follow-up of 60.1 months (range, 48-108 months). Generalized ligamentous laxity was assessed in all patients. The Karlsson-Peterson ankle score (Karlsson score), talar tilt angle, and anterior displacement of the talus were used to evaluate clinical and radiological outcomes. Risk factors associated with clinical outcomes were evaluated using bivariate analysis and logistic regression analysis. Survival outcomes were compared using Kaplan-Meier analysis.

RESULTS

Generalized ligamentous laxity was evident in 42 cases (21.1%). The average Karlsson score improved from 54.6 ± 7.1 preoperatively to 87.9 ± 7.2 at last follow-up (P < .001). The presence of generalized ligamentous laxity was significantly associated with poor clinical and radiological outcomes. The rates of clinical failure were 10.8% and 45.2% in the nonlaxity group and the laxity group, respectively (P < .001). According to bivariate analysis, generalized ligamentous laxity, syndesmosis widening, osteochondral lesion of the talus, high preoperative talar tilt angle (>15°), and high preoperative anterior displacement of the talus (>10 mm) were significantly associated with clinical failure. Multivariate logistic regression analysis revealed that generalized ligamentous laxity was the most important independent predictor of clinical failure after the modified Broström procedure. The cumulative success rates for the nonlaxity group were significantly superior to those for the laxity group in Kaplan-Meier curves (P < .001).

CONCLUSION

Generalized ligamentous laxity is an independent predictor of poor outcomes and a risk factor of recurrent instability following the modified Broström procedure for CLAI.

Spinal Accessory Nerve: Ultrasound Findings and Correlations with Neck Lymph Node Levels

Purpose: To evaluate the ultrasound characteristics of the spinal accessory nerve (SAN) and correlate nerve location with neck lymph node level. Materials and Methods: 50 participants with 100 SANs were enrolled in this study. The SAN was traced from the trapezius muscle to the upper neck and was identified by a hypoechoic linear structure without color Doppler flow. The ultrasound characteristics of the SAN, such as visibility, diameter, relationship with adjacent structures, and its correlation with lymph node levels, were evaluated. Results: The SAN was identified in 96 %-100 % of segments. The mean diameter of the SAN was 0.54 ± 0.09 mm. The SANs was located between the trapezius and levator scapulae muscles and 90.8 % were traced into the trapezius muscle. In the upper neck, the SAN passed deep into the sternocleidomastoid (SCM) muscle in 38 % of cases and between the two heads of the SCM muscle in 62 % of cases. The SAN was found at neck lymph node levels II, III, IV, and V, but not I or VI. Conclusion: Continuous ultrasound monitoring of the SAN and its correlation with lymph node levels is possible in most patients. Our current findings may assist in the future prevention of SAN injury during ultrasound-guided procedures.

Preoperative repeat endoscopy for colorectal cancer: What is its role and when is it necessary?

SUMMARY

Many surgeons consider repeat endoscopy to be the standard of care for colorectal cancer; however, its utility in the preoperative setting is not well understood, especially given the lack of standardized guidelines on appropriate tumour localization and colonoscopic reporting. This often results in patients undergoing an unnecessary medical procedure during their preoperative evaluation. We discuss some of the issues surrounding the practice of preoperative repeat endoscopy as well as patient perspectives on the procedure. Our observations suggest that repeat endoscopy in the setting of colorectal cancer surgery may play a role in enabling transition of patient care between the initial endoscopist and the treating surgeon and in improving the patient experience. Patients with operable colorectal cancer appear to understand and support the current use of repeat endoscopy. However, improving preoperative care will require further research and ultimately the development of evidence-based clinical guidelines.

Hyaluronic Acid Dressing in the Treatment of Diabetic Foot Ulcer

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.

Treatment Outcomes of Chronic Lateral Ankle Instability Associated with Mild Cavovarus Deformity

Category:

Ankle

Introduction/Purpose:

Chronic lateral ankle instability (CLAI) has shown significant relationship with cavovarus deformity in prior studies. Isolated lateral ankle ligament reconstruction in patients who have CLAI with cavovarus deformity has been shown poor outcome if the deformity had not been corrected. Traditionally, cavovarus foot has been associated with neuromuscular conditions, however, nowadays it occurs in a less severe form even in the normal population. Mild cavovarus deformity is thought to be an anatomical risk factor for CLAI, but there are still debates on the correction of the mild deformity. The purpose of the current study was to evaluate clinical and radiographic outcomes of the modified Broström operation (MBO)s with additional procedures for the CLAI with mild cavovarus deformity.

Methods:

We reviewed total 12 patients who underwent MBOs with additional procedures for CLAI with mild cavovarus deformity between August 2009 and September 2013. Patients were evaluated by visual analogue scale (VAS) for pain, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the Karlsson-Peterson (KP) ankle score. The talar tilt angle and the anterior displacement of the talus on ankle stress radiographs and the first metatarsal- talus angle, the arch height between cuneiform and fifth metatarsal base and the calcaneal pitch angle on foot lateral standing radiographs were examined.

Results:

The mean follow-up period was 31.5 months. Calcaneal lateral closing wedge osteotomy was performed in 6 patients to correct fixed hindfoot varus, and first metatarsal dorsiflexion osteotomy in 9 patients to correct remnant plantarflexion of the first ray. Three of 12 patients underwent both calcaneal and first metatarsal osteotomies. The mean VAS score decreased from 5.5 to 1.7 at last follow-up (p=0.002). The mean AOFAS score and the mean KP ankle score were significantly improved (61.0 to 85.3 (p< 0.001), 56.8 to 83.1 (p < 0.001)) and there was no recurrence of instability. Radiographically, the mean talar tilt angle and the anterior displacement of the talus were decreased (p=0.001, p=0.007), and the first metatarsal- talus angle and the arch height were decreased at last follow-up (p=0.001, p=0.003).

Conclusion:

Concomitant correction of mild cavovarus deformity with MBO for CLAI improves clinical outcomes and prevents recurrent instability. A comprehensive evaluation and cautious approach for deformity should be followed when treating patients with chronic ankle instability.

Collagen Dressing in the Treatment of Diabetic Foot Ulcer

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.

Arthritis in the First Metatarsophalangeal Joint After Proximal Opening Wedge Osteotomy for Moderate to Severe Hallux Valgus Deformity

Category:

Bunion

Introduction/Purpose:

Over recent years, a proximal opening wedge osteotomy (POWO) using a novel low-profile plate have gained in popularity for the correction of moderate to severe hallux valgus. However, the proximal opening wedge osteotomy was known to increase the length of the first metatarsal, resulting in tightening of the soft tissues around the first metatarsophalangeal (MTP) joint and predisposing to jamming of the joint and subsequent arthritis. The purpose of this study was to evaluate the arthritic change of first MTP joint after POWO using a low-profile plate for correction of moderate to severe hallux valgus.

Methods:

We retrospectively reviewed 100 consecutive POWOs using a low-profile plate performed in 87 patients with moderate to severe hallux valgus deformity. After excluding 17 cases, 83 cases in 73 patients were included. For clinical assessment, VAS, the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score and Foot and Ankle Outcome Score (FAOS) were obtained. The hallux valgus angle (HVA), the intermetatarsal angle (IMA), the relative first metatarsal length which is the first metatarsal length divided by the second metatarsal length and the first MTP joint radiographic arthritic grade by Coughlin and Shurnas were assessed on standard weight bearing radiographs of the foot for radiographic evaluation.

Results:

Mean follow-up period was 16.1 (12-45) months. The mean VAS, AOFAS score and most of FAOS subscales improved significantly. Significant corrections in the HVA and IMA were obtained and the mean increase in the relative first metatarsal length was 3.8% at last follow-up (P < 0.001). There were 15 (18.1%, 15/83) cases of the first MTP joint arthritis at last follow-up (Radiographic grade I: 5, II: 8, III: 2). Of 62 cases using a large wedge plate (≥5.0 mm), 12 (19.4%, 12/62) cases showed poorer outcomes and a significant progression of the arthritic grade at last follow-up (Fisher's exact test, P=0.031) comparing to using a small wedge plate (< 5.0 mm) (Table 1).

Conclusion:

The POWO using a low-profile wedge plate is effective and reproducible technique for correction of moderate to severe hallux valgus deformity. However, the exacerbation of preexisting first MTP joint arthritis and the subsequent arthritis can occur after POWOs using a large wedge plate (≥5.0 mm) at short to mid-term follow-up. Therefore, POWOs with a low-profile wedge plate should be used judiciously for correction of moderate to severe hallux valgus.

Hyaluronic Acid Injection After Failed Arthroscopic Microfracture in Osteochondral Lesion of the Talus

Category:

Ankle

Introduction/Purpose:

The optimal treatment for symptomatic osteochondral lesion of the talus (OLT) after failed arthroscopic microfracture has been a controversial issue. The use of viscosupplementation for treatment of OLT has been gradually increasing. The hyaluronic acid (HA) injection is believed to play an important role in reducing pain and inflammation, and promoting tissue repair. The purpose of this study is to evaluate the clinical outcomes of intra-articular HA injection for the patients with failed arthroscopic microfracture in OLT.

Methods:

This study included 12 patients who received three weekly injections of intra-articular HA after arthroscopic microfracture for OLT between October 2014 and October 2015. Five men and seven women were included in this study. The average age at the time of injection was 41 years (range, 19-63 years). All patients had recurrent pain for at least 6 months after the index surgery. The patients were followed for 6.1 months (range: 5.0-7.0). At each visit, the efficacy of HA injection was evaluated by a Visual Analog Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score and Foot and Ankle Outcome Score (FAOS) pain subscale. 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 decreased from 6.7 ± 1.1 at pre-injection to 2.4 ± 1.6 at post-injection six weeks (p < 0.001), 3.1 ± 1.5 at three months (p = 0.002) and 3.8 ± 2.3 at six months (p = 0.02). Mean AOFAS score improved from 61.0 ± 9.1 at pre-injection to 85.3 ± 11.3 at post-injection six weeks (p < 0.001), 82.9 ± 10.4 at three months (p < 0.001) and 80.4 ± 13.8 at six months (p = 0.001). Mean FAOS pain subscale also improved from 53.2 ± 4.2 at pre-injection to 71.1 ± 9.4 at post-injection six weeks (p < 0.001), 66.7 ± 7.2 at three months (p = 0.001) and 64.4 ± 9.5 at six months (p = 0.036). According to the Alexander scale, there were 58.3% (7/12) good, 25.0% (3/12) fair, and 16.7% (2/12) poor results at post-injection six months. There was no adverse effect.

Conclusion:

In this study, we found that the main improvement in clinical outcomes occurred during the first six weeks and significantly maintained until at least three or six months. We believe that the HA injection could be a useful treatment option after failed arthroscopic microfracture in OLT.

Cell recruiting chemokine-loaded sprayable gelatin hydrogel dressings for diabetic wound healing

In this study, we developed horseradish peroxidase (HRP)-catalyzed sprayable gelatin hydrogels (GH) as a bioactive wound dressing that can deliver cell-attracting chemotactic cytokines to the injured tissues for diabetic wound healing. We hypothesized that topical administration of chemokines using GH hydrogels might improve wound healing by inducing recruitment of the endogenous cells. Two types of chemokines (interleukin-8; IL-8, macrophage inflammatory protein-3α; MIP-3α) were simply loaded into GH hydrogels during in situ cross-linking, and then their wound-healing effects were evaluated in streptozotocin-induced diabetic mice. The incorporation of chemokines did not affect hydrogels properties including swelling ratio and mechanical stiffness, and the bioactivities of IL-8 and MIP-3α released from hydrogel matrices were stably maintained. In vivo transplantation of chemokine-loaded GH hydrogels facilitated cell infiltration into the wound area, and promoted wound healing with enhanced re-epithelialization/neovascularization and increased collagen deposition, compared with no treatment or the GH hydrogel alone. Based on our results, we suggest that cell-recruiting chemokine-loaded GH hydrogel dressing can serve as a delivery platform of various therapeutic proteins for wound healing applications.

STATEMENT OF SIGNIFICANCE

Despite development of materials combined with therapeutic agents for diabetic wound treatment, impaired wound healing by insufficient chemotactic responses still remain as a significant problem. In this study, we have developed enzyme-catalyzed gelatin (GH) hydrogels as a sprayable dressing material that can deliver cell-attracting chemokines for diabetic wound healing. The chemotactic cytokines (IL-8 and MIP-3α) were simply loaded within hydrogel during in situ gelling, and wound healing efficacy of chemokine-loaded GH hydrogels was investigated in STZ-induced diabetic mouse model. These hydrogels significantly promoted wound-healing efficacy with faster wound closure, neovascularization, and thicker granulation. Therefore, we expect that HRP-catalyzed in situ forming GH hydrogels can serve as an injectable/sprayable carrier of various therapeutic agents for wound healing applications.

Hyaluronic acid dressing (Healoderm) in the treatment of diabetic foot ulcer: A prospective, randomized, placebo-controlled, single-center study

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. To examine the sole effectiveness of HA in DFU treatment, a prospective, randomized, placebo-controlled, single-center study was conducted using an HA dressing without additional substances. Thus, 34 patients who met the inclusion criteria were randomized into two groups (the study group: HA dressing material; the control group: conventional dressing material). During the 12-week study period, 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. At the end of the study, 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]. Additionally, faster ulcer healing velocity and shorter mean duration for achieving a 50% ulcer size reduction were observed in the study group (P = 0.022 and 0.004, respectively). The Kaplan-Meier survival 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 = 0.0127). Finally, there were no adverse events related to the dressing materials used in the study. As a major component of the extracellular matrix, this study supports the safety and efficacy of a pure HA dressing without additional substances in treating DFU.

Development of Stabilized Growth Factor-Loaded Hyaluronate- Collagen Dressing (HCD) matrix for impaired wound healing

BACKGROUND

Diabetes mellitus is a disease lack of insulin, which has severely delayed and impaired wound healing capacity. In the previous studies, various types of scaffolds and growth factors were used in impaired wound healing. However, there were several limitations to use them such as short half-life of growth factors in vivo and inadequate experimental conditions of wound-dressing material. Thus, our study aimed to determine the biocompatibility and stability of the matrix containing structurally stabilized epidermal growth factor (S-EGF) and basic fibroblast growth factor (S-bFGF).

RESULTS AND DISCUSSION

We stabilized EGF and bFGF that are structurally more stable than existing EGF and bFGF. We developed biocompatible matrix using S-EGF, S-bFGF, and hyaluronate- collagen dressing (HCD) matrix. The developed matrix, S-EGF and S-bFGF loaded on HCD matrix, had no cytotoxicity, in vitro. Also, these matrixes had longer releasing period that result in enhancement of half-life. Finally, when these matrixes were applied on the wound of diabetic mice, there were no inflammatory responses, in vivo. Thus, our results demonstrate that these matrixes are biologically safe and biocompatible as wound-dressing material.

CONCLUSIONS

Our stabilized EGF and bFGF was more stable than existing EGF and bFGF and the HCD matrix had the capacity to efficiently deliver growth factors. Thus, the S-EGF and S-bFGF loaded on HCD matrix had improved stability. Therefore, these matrixes may be suitable for impaired wound healing, resulting in application of clinical treatment.