Heterotopic ossification which may develop around the elbow in patients with burns may lead to severe functional impairment. We describe the outcome of early excision of such heterotopic ossification in 28 patients (35 elbows), undertaken as soon as the patient’s general and local condition allowed. The mean age at operation was 42 years. The mean area of burnt body surface was 49%. The mean pre-operative range of movement was 22° in flexion/extension and 94° in pronation/supination. The mean time between the burn and operation was 12 months with the median being 9.5. The mean follow-up period was for 21 months. At the last review, the mean range of movement was 123° in flexion/extension and 160° in pronation/supination. Clinical evidence of recurrence was seen in four patients, occurring within the first two months after operation. Nevertheless, three of these elbows gained 60° or more in flexion/extension and in pronation/supination. Based on this experience, we recommend early surgical treatment of heterotopic ossification of the elbow in patients with severe burns

Full-thickness burns around the knee can involve the extensor mechanism. The gastrocnemius flap is well described for soft tissue reconstruction around the knee. We describe a method where a Whichita Fusion Nail¯ knee arthrodesis, combined with a medial gastrocnemius muscle flap was used to salvage the knee and preserve the lower leg following a full-thickness contact burn. The gastrocnemius flap for wound coverage of an open knee joint was originally described in 1970 and remains the workhorse for soft tissue knee reconstruction. There are a number of local alternatives including the vastus lateralis, medialis and sartorius flap; and perforator flaps such as the medial sural artery perforator island flap and islanded posterior calf perforator flap, however many of these are unsuitable for larger defects. Full-thickness burns around the knee can put the extensor mechanism at risk and subsequent rupture is a possible consequence. The gastrocnemius flap has been used to cover a medial knee defect with exposed joint cavity following a burn and also been used in post burn contracture release around the knee. The primary indication for Wichita fusion nail is a failed total knee replacement. It allows intramedullary stabilization with compression at the arthrodesis site to stimulate bone union. With fusion rates reported up to 100% and low complication rates as compared to other methods of fusion, the technique has a useful role in limb salvage type procedures. While use of the gastrocnemius flap in knee burns has been described before we believe this is the first time that this combination of techniques, namely knee arthrodesis with soft tissue reconstruction using a gastrocnemius flap, has been reported. Combining these procedures with a multidisciplinary approach provides a useful alternative leading to limb salvage and avoiding the need for an above knee amputation when extensor reconstruction is not possible

Ten patients with 13 ankylosed elbows after burns are described. Six elbows, fixed in nearly full extension, had almost total functional disability; the other seven had varying amounts of deformity. In five of the 13 elbows there was a continuous bony mass with loss of the joint space; these were treated by a modified excision arthroplasty which restored good movement and useful function, though there was some lateral laxity. Six elbows had a posterior bony block; this was excised, which restored a useful arc of movement. The literature on bony ankylosis after burns is reviewed and the management of these cases in a developing country is described

Aims. Physician burnout and its consequences have been recognized as increasingly prevalent and important issues for both organizations and individuals involved in healthcare delivery. The purpose of this study was to describe and compare the patterns of self-reported wellness in orthopaedic surgeons and trainees from multiple nations with varying health systems. Methods. A cross-sectional survey of 774 orthopaedic surgeons and trainees in five countries (Australia, Canada, New Zealand, UK, and USA) was conducted in 2019. Respondents were asked to complete the Mayo Clinic Well-Being Index and the Stanford Professional Fulfillment Index in addition to 31 personal/demographic questions and 27 employment-related questions via an anonymous online survey. Results. A total of 684 participants from five countries (Australia (n = 74), Canada (n = 90), New Zealand (n = 69), UK (n = 105), and USA (n = 346)) completed both of the risk assessment questionnaires (Mayo and Stanford). Of these, 42.8% (n = 293) were trainees and 57.2% (n = 391) were attending surgeons. On the Mayo Clinic Well-Being Index, 58.6% of the overall sample reported feeling burned out (n = 401). Significant differences were found between nations with regards to the proportion categorized as being at risk for poor outcomes (27.5% for New Zealand (19/69) vs 54.4% for Canada (49/90) ; p = 0.001). On the Stanford Professional Fulfillment Index, 38.9% of the respondents were classified as being burned out (266/684). Prevalence of burnout ranged from 27% for Australia (20/74 up to 47.8% for Canadian respondents (43/90; p = 0.010). Younger age groups (20 to 29: RR 2.52 (95% confidence interval (CI) 1.39 to 4.58; p = 0.002); 30 to 39: RR 2.40 (95% CI 1.36 to 4.24; p = 0.003); 40 to 49: RR 2.30 (95% CI 1.35 to 3.9; p = 0.002)) and trainee status (RR 1.53 (95% CI 1.15 to 2.03 p = 0.004)) were independently associated with increased relative risk of having a ‘at-risk’ or ‘burnout’ score. Conclusions. The rate of self-reported burnout and risk for poor outcomes among orthopaedic surgeons and trainees varies between countries but remains unacceptably high throughout. Both individual and health system characteristics contribute to physician wellness and should be considered in the development of strategies to improve surgeon wellbeing. Level of Evidence: III. Cite this article: Bone Jt Open 2021;2(11):932–939

We present the case of a 63-year-old woman who sustained an acrylic cement burn of the sciatic nerve at hip replacement. She was treated by resection of the damaged segment and grafting. Electron microscopy showed that the nerve was nearly normal 1 cm from the cement margin indicating that this is a safe level for resection

We have carried out a prospective, randomised trial to measure the rise of temperature during reaming of the tibia before intramedullary nailing. We studied 34 patients with a mean age of 35.1 years (18 to 63) and mean injury severity score of 10 (9 to 13). The patients were randomised into two groups: group 1 included 18 patients whose procedure was undertaken without a tourniquet and group 2, 16 patients in whom a tourniquet was used. The temperature in the bone was measured directly by two thermocouples inserted into the cortical bone near the isthmus of the tibial diaphysis. Reaming was carried out to at least 1.5 mm above the required diameter of the nail. Blood loss was assessed by recording the preoperative and postoperative haemoglobin (Hb) level.

The minimum clinical follow-up was six months. In group 1 (no tourniquet), the mean Hb dropped 2.8 g/dl from 14.3 ± 1.02 g/dl to 11.5 ± 1.04 g/dl (p = 0.0001), whereas with the tourniquet, the mean decrease was 1.3 g/dl from 14 ± 1 g/dl to 12.7 ± 1.3 g/dl (p = 0.007). This difference was not statistically significant. The mean initial tibial temperature was 35.6°C (sd 0.6) and rose with reaming to levels between 36.3°C and 51.6°C. The highest temperatures were obtained with the largest reamers (11 and 12 mm, p = 0.0001) and the most rapid rise with the smallest diameters of medullary canal (8 or 9 mm). The rise of temperature was transient (20s).

We were unable to identify any effect of the use of a tourniquet on the temperature achieved. Reamed intramedullary tibial nailing induces a transient elevation of temperature which is directly related to the amount of reaming.

Tourniquet is a commonly used tool in orthopaedic practice. Incidence of complications is low but if any develops, it is devastating. Transient nerve damage, ischemia or skin burns are the possible tourniquet related complications. There is big variation in practice regarding the limb occlusion pressure. 51 procedures in 50 patients were reviewed retrospectively in our district general hospital. We looked at quality of documentation guided by the BOAST standard (The Safe Use of Intraoperative Tourniquets, published in October 2021). Limb occlusion pressure and ischemic time were analysed. Intra-operative and post-operative notes were reviewed to assess quality of documentation and post-operative complications. Although limb occlusion pressure was above the recommended range in more than 75% of cases, there were no significant complications observed. Two cases only developed transient neuropraxia in common peroneal nerve and median nerve following tibial plateau ORIF and trapeziectomy simultaneously. Tibial ORIF fixation case had prolonged ischemic time (more than 120 minutes) and the limb occlusion pressure for the hand case was above the recommended range. Both have recovered within few days with no long-term consequences. Minimum documentation threshold was not met with regarding tourniquet site condition, method of skin isolation and padding, and exsanguination method. This relatively new standard with no previous similar guidance needs time until it is followed by the health care professionals especially when there is no high incidence of complications related to the use of the tourniquet. However, it is crucial to increase the theatre staff awareness of such standards. This will prevent devastating complications specifically in vulnerable patients. Adjustments to theatre checklist have been suggested to improved documentation. Additionally, local teaching sessions will be delivered to theatre personnel aiming at improving our compliance to this standard

Major orthopaedic fractures are an independent risk factor for the development of venous thromboembolism (VTE), which are significant causes of preventable morbidity and mortality in trauma patients. Despite thromboprophylaxis, patients who sustain a pelvic or acetabular fracture (PA) continue to have high rates of VTE (12% incidence). Thrombelastography (TEG) is a whole-blood, point-of-care test which provides an overview of the clotting process. Maximal amplitude (MA), from TEG analysis, is the measure of clot strength and values ≥65mm have been used to quantify hypercoagulability and increased VTE risk. Therefore, the primary aim was to use serial TEG analysis to quantify the duration of hypercoagulability, following surgically treated PA fractures. This is a single centre, prospective cohort study of adult patients 18 years or older with surgically treated PA fractures. Consecutive patients were enrolled from a Level I trauma centre and blood draws were taken over a 3-month follow-up period for serial TEG analysis. Hypercoagulability was defined as MA ≥65mm. Exclusion criteria: bleeding disorders, active malignancy, current therapeutic anticoagulation, burns (>20% of body surface) and currently, or expecting to become pregnant within study timeframe. Serial TEG analysis was performed using a TEG6s hemostasis analyzer (Haemonetics Corp.) upon admission, pre-operatively, on post-operative day (POD) 1, 3, 5, 7 (or until discharged from hospital, whichever comes sooner), then in follow-up at 2-, 4-, 6-weeks and 3-months post-operatively. Patients received standardized thromboprophylaxis with low molecular weight heparin for 28 days post-operatively. VTE was defined as symptomatic DVT or PE, or asymptomatic proximal DVT, and all participants underwent a screening post-operative lower extremity Doppler ultrasound on POD3. Descriptive statistics were used to determine the association between VTE events and MA values. For the primary outcome measure, the difference between the MA threshold value (≥65mm) and serial MA measures, were compared using one-sided t-tests (α=0.05). Twenty-eight patients (eight females, 29%) with a mean age of 48±18 years were included. Acetabular fractures were sustained by 13 patients (46%), pelvic fractures by 14 patients (50%), and one patient sustained both. On POD1, seven patients (25%) were hypercoagulable, with 21 patients (78%) being hypercoagulable by POD3, and 17 patients (85%) by POD5. The highest average MA values (71.7±3.9mm) occurred on POD7, where eight patients (89%) were hypercoagulable. At 2-weeks post-operatively, 16 patients (94%) were hypercoagulable, and at four weeks, when thromboprophylaxis was discontinued, six patients (40%) remained hypercoagulable. Hypercoagulability persisted for five patients (25%) at 6-weeks and for two patients (10%) by three months. There were six objectively diagnosed VTE events (21.4%), five were symptomatic, with a mean MA value of 69.3mm±4.3mm at the time of diagnosis. Of the VTE events, four occurred in participants with acetabular fractures (three male, 75%) and two in those with pelvic fractures (both males). At 4-weeks post-operatively, when thromboprophylaxis is discontinued, 40% of patients remained hypercoagulable and likely at increased risk for VTE. At 3-months post-operatively, 10% of the cohort continued to be hypercoagulable. Serial TEG analysis warrants further study to help predict VTE risk and to inform clinical recommendations following PA fractures

Instances of skin burns whilst splitting orthopaedic casts using oscillating plaster saws have been reported. Previous work has found contact temperatures over 65°C to burn skin within a second. We compared saw blade temperatures generated whilst splitting casts using two blades, two cutting techniques, with and without a dust extraction vacuum. Gypsona (Smith & Nephew Healthcare), Scotchcast Poly, Scotchcast Softcast and Scotchcast Plus Fibreglass (3M Healthcare) casts were formed by applying casting material to PVC pipe over cast padding and stockingette. Casts were left for one week to dry and then split using an all-purpose cast saw blade and a mortuary saw blade (de Soutter) fitted to a CleanCast CC5 oscillating saw (de Soutter). This saw has an inbuilt vacuum dust extraction system; casts were split with this system turned on and off, using the standard ‘up-down’ technique and a dragging technique. Blade temperatures were recorded during splitting using a digital thermometer (DS18B20, Dallas Semiconductors) fixed to the blade. Average maximum blade temperatures from five cuts were calculated and statistical analysis conducted. Splitting synthetic casts with an ‘up-down’ technique generated higher temperatures than splitting gypsona (softcast +5.5°C p=0.06, fibreglass +9.0°C p=0.03, polyester +20.0°C p<0.001). Mortuary blades generated similar temperatures to cast saw blades except whilst splitting fibreglass (+5.6°C p=0.031). Compared to the ‘up-down’ technique, the ‘dragging’ technique generated higher blade temperatures irrespective of material (gypsona +10.7°C p=0.005, softcast +7.1°C p=0.001, fibreglass +16.6°C p=0.001, polyester +11.4°C p=0.001). The vacuum dust extraction system reduced temperature irrespective of material being split (gypsona -12.4°C p=0.002, softcast - 20.7°C p<0.001, fibreglass -19.2°C p=0.001, polyester -29.1 p<0.001). Blade temperatures whilst splitting synthetic casts were significantly higher than whilst splitting gypsona. The vacuum dust extraction system cooled blades to a temperature at which thermal skin burns cannot occur

The number of total knee arthroplasties continues to increase annually with over 90,000 total knee replacements performed in the United Kingdom in 2018. Multiple national bodies including the British Association for Surgery of the Knee (BASK) and the British Orthopaedic Association collaborated in July 2019 to produce best practice guidance for knee arthroplasty surgery. This study aims to review practice in a regional healthcare trust against these guidelines. Fifty total knee replacement operation notes were reviewed between January and February 2020 from 11 different consultant orthopaedic surgeons. Documents were assessed against 17 criteria recommended by the BASK guidance. Personnel names and grades were generally well documented. Tourniquet time and pressure were documented in over 98% of operation notes however, protection from spirit burns was not documented at all. Trialling and soft tissue balancing was well recorded in 100% and 96% of operation notes respectively. Areas lacking in documentation included methods utilised to optimise cementation technique and removal of cement debris. Protection of key knee structures was documented in only 56% of operation notes clearly. Prior to closure, final assessment of mechanism integrity, collateral ligament was not documented at all and final ROM after implantation of components was recorded 34% of the time. Subsequently authors have created a universal operation note template, uploaded onto the patient electronic notes, which prompts surgeons to complete documentation of the relevant criteria advocated by BASK. In conclusion, detailed and systematic documentation is vital to prevent adverse events and reduce the risk of litigation. By producing detailed operative templates this risk can be mitigated

Heterotopic ossification (HO) is the formation of bone at extra-skeletal sites. Genetic diseases, traumatic injuries, or severe burns can induce this pathological condition and can lead to severe immobility. While the mechanisms by which the bony lesions arise are not completely understood, intense inflammation associated with musculoskeletal injury and/or highly invasive orthopaedic surgery is thought to induce HO. The incidence of HO has been reported between 3% and 90% following total hip arthroplasty. While the vast majority of these cases are asymptomatic, some patients will present decreased range of motion and painful swelling around the affected joints leading to severe immobility. In severe cases, ectopic bone formation may be involved in implant failure, leading to costly and painful revision surgery. The effects of surgical-related intraoperative risk factors for the formation of HO can also play a role. Prophylactic radiation therapy, and anti-inflammatory and biphosphonates agents have shown some promise in preventing HO, but their effects are mild to moderate at best and can be complicated with adverse effects. Irradiation around surgery could decrease the incidence of HO. However, high costs and the risk of soft tissue sarcoma inhibit the use of irradiation. Increased trials have demonstrated that nonsteroidal anti-inflammatory drugs (NSAID) are effective for the prevention of HO. However, the risk of gastrointestinal side effects caused by NSAID has drawn the attention of surgeons. The effect of the selective COX-2 inhibitor, celecoxib, is associated with a significant reduction in the incidence of HO in patients undergoing THA. Bone morphogenetic proteins (BMP) such as BMP2 identified another novel druggable target, i.e., the remote application of apyrase (ATP hydrolyzing agent) in the burn site decreased HO formation and mitigated functional impairment later. The question is if apyrase can be safely administered through other, such as systematical, routes. While the systemic treatments have shown general efficacy and are used clinically, there may be great benefit obtained from more localised treatment or from more targeted inhibitors of osteogenesis or chondrogenesis. In the surgical setting, prophylaxis for HO is regularly indicated due to the considerable risk of functional impairment. Heterotopic ossification is a well-known complication of total hip arthroplasty, especially when the direct lateral approach is used. Possible intraoperative risks are the size of incision, approach, duration of surgery and gender that can be associated with higher rates of HO or increase of the severity of HO. Like inflammation and tissue damage/ischemia are likely to be the key in the formation of HO, kindness to the soft tissues, tissue preserving surgery, pulse lavage to remove bone inducing factors and avoiding damage to all tissues should be erased as a comorbidity. Incision length, tissue dissection and subsequent localised trauma and ischemia, blood loss, anesthetic type and length of surgery may all contribute to the local inflammatory response. Data suggest that the surgeon may control the extent and nature of HO formation by limiting the incision length and if possible the length of the operation. Currently resection of HO is generally suggested after complete maturation (between 14–18 months), since earlier intervention is thought to predispose to recurrence. Reliable indicators of maturation of HO are diminishing activity on serial bone scans and/or decreasing levels of alkaline phosphatase. Although usually asymptomatic, heterotopic bone formation can cause major disability consisting of pain and a decreased range of motion in up to 7% of patients undergoing THA. Patients benefit from early resection of the heterotopic ossification with a proper and reliable postoperative strategy to prevent recurrence of HO with clinical implications

Objectives. Injectable Bromelain Solution (IBS) is a modified investigational derivate of the medical grade bromelain-debriding pharmaceutical agent (NexoBrid) studied and approved for a rapid (four-hour single application), eschar-specific, deep burn debridement. We conducted an ex vivo study to determine the ability of IBS to dissolve-disrupt (enzymatic fasciotomy) Dupuytren’s cords. Materials and Methods. Specially prepared medical grade IBS was injected into fresh Dupuytren’s cords excised from patients undergoing surgical fasciectomy. These cords were tested by tension-loading them to failure with the Zwick 1445 (Zwick GmbH & Co. KG, Ulm, Germany) tension testing system. Results. We completed a pilot concept-validation study that proved the efficacy of IBS to induce enzymatic fasciotomy in ten cords compared with control in ten cords. We then completed a dosing study with an additional 71 cords injected with IBS in descending doses from 150 mg/cc to 0.8 mg/cc. The dosing study demonstrated that the minimal effective dose of 0.5 cc of 6.25 mg/cc to 5 mg/cc could achieve cord rupture in more than 80% of cases. Conclusions. These preliminary results indicate that IBS may be effective in enzymatic fasciotomy in Dupuytren’s contracture. Cite this article: Dr G. Rubin. A new bromelain-based enzyme for the release of Dupuytren’s contracture: Dupuytren’s enzymatic bromelain-based release. Bone Joint Res 2016;5:175–177. DOI: 10.1302/2046-3758.55.BJR-2016-0072

Radio Frequency Ablation (RFA) is a precise CT-guided technique to generate a small pre-defined field of dissecated tissue. Its’ present use in orthopaedic oncology is to treat osteoid osteoma. We have also treated other lesions with RFA and want to report our present indications and complications. From 2005 to 2008 we performed 30 procedures: 23 osteoid osteomas, five low-grade chondrosarcomas, one chondroblastoma and one thyroid metastasis. Localisations were femur in 14 cases, tibia in 10, calcaneus in two, fibula in two, sacrum in one and scapula in one. All patients were treated with CT- guided RFA (Boston Scientific). Follow-up for osteoid osteoma was done without additional imaging, all patients but one were pain free within 2 weeks; this one patient proved to have a chronic osteomyelitis although we thought we saw a nidus on CT. In one patient a burn wound complicated treatment because of unnoticed damage of the isolation layer of the probe. A free skin graft was necessary. We performed MRI controls and curettages for the chondrosarcomas in three patients, in one patient a fracture developed in the calcar femoris region after three months and a hip replacement was done. The patient with chondroblastoma is followed by MRI and there is no activity on contrast MRI two years after the procedure. In one lady a RFA was done for thyroid metastasis in the calcar femoris region. She fractured her collum femoris and got a hip replacement. In all tissue retrieved after RFA (curettage and hip replacement), there was complete necrosis of the tumour (chondrosarcoma grade one and thyroid metastasis). RFA is an effective procedure for osteoid osteoma. Fracture and skin burns can occur. It is promising in low-grade chondrosarcoma and chondroblastoma. A study has been initiated recently to evaluate effectiveness of RFA in low-grade chondrosarcoma < 4 cm

Introduction: Knee arthroscopy is one of the most commonly performed orthopaedic procedures. All orthopaedic surgeons have heard anecdotal stories of thermal injury and drape combustion, yet a literature search has failed to find any papers reviewing the nature of such risks. Materials and methods: A thermocouple attached to a laptop computer was used to record the temperature at the arthroscope tip, the light cable end and the light source generator. All potentially flammable materials commonly used during arthroscopic surgery (various disposable drapes, cotton drapes, gowns, paper towels and swabs), were placed at measured distances from a) the light cable end and b) the arthroscope tip. Results: The arthroscope tip reached a maximum temperature of 41.90° in 200 seconds. The light cable tip reached 80° at 100 seconds and a maximum temperature of 110°C in 342 seconds. The light source generator reached a temperature of 153°C. All materials tested (except cotton swabs) underwent signs of combustion. The disposable drapes burnt most rapidly. None of the materials considered had any evidence of thermal damage when placed at distances of 2.5 cm beyond the light cable and 0.5 cm beyond the arthroscope tip. Combustion was most rapid at a distance of 5mm from the instruments. Most surgeons consider the arthroscope tip or light cable end to be the site most likely to induce combustion. Fuel, heat and oxygen are required to produce combustion. Direct contact with the tip results in greater exposure to heat but lower oxygen availability. The fasted combustion occurred at 5mm due to higher oxygen availability despite a lower temperature. Conclusions and Recommendations:. Disposable drapes will burn with the light cable and the arthroscope tip. The arthroscope tip and light cable end should not be left to rest against the drapes because thermal burns can occur within seconds. A kidney dish should be used to contain the instruments when not in the surgeon’s hands. The light source should be switched on only when the light cable is connected to the arthroscope. A retractable shield of 2.5mm is fitted to the light cable end

Introduction. This study reviews the orthopaedic care of the thirteen patients who were admitted and treated at Royal Manchester Children's' Hospital following the Manchester Arena Bomb blast. Methods. We included all children admitted to Royal Manchester Children's Hospital injured following the bomb blast who either suffered upper limb, lower limb or pelvic fractures, or penetrating upper or lower limb wounds. The nature of each patient's bone and soft tissue injuries, initial and definitive management, and outcome were assessed and documented. Main outcome measures were time to fracture union, time to definitive soft tissue/skin healing, and functional outcome. Findings. Thirteen children were admitted with orthopaedic injuries; 12 were female and mean age was 12.69. All patients had penetrating deep wounds with at least one large nut foreign body in situ, two patients suffered significant burn injury, one patient required amputation of two digits, and two patients required local flap reconstruction. There were a total of 29 upper and lower limb fractures in nine of the patients, with the majority managed without internal or external fixation. In only half of the patients all fractures showed full radiological union at 6 months follow up. There was significant morbidity with several patients suffering long term physical and psychological disability and one patient still in hospital. Conclusion. We found that stable fractures in children secondary to blast injuries can often be appropriately managed without metalwork, and penetrating wounds can be managed without the need for skin graft/flap reconstruction. Our study documents the severe nature of the injuries suffered by paediatric survivors of the Manchester Arena bomb blast. It highlights the demands on a trauma unit following such an event

Aims

Paediatric fractures are highly prevalent and are most often treated with plaster. The application and removal of plaster is often an anxiety-inducing experience for children. Decreasing the anxiety level may improve the patients’ satisfaction and the quality of healthcare. Virtual reality (VR) has proven to effectively distract children and reduce their anxiety in other clinical settings, and it seems to have a similar effect during plaster treatment. This study aims to further investigate the effect of VR on the anxiety level of children with fractures who undergo plaster removal or replacement in the plaster room.

Scar tissue formation between nerve and surrounding muscle is one of the most undesired occurrence in nerve surgery In order to prevent scar tissue apposition after surgery, a lot of biocompatible products have been developed and tested first of all on animal models and then in surgical practice. we tested the efficacy of a CMC-PEO gel in reduction of perineural scar tissue formation in a mice model and in a small group of patients. We performed surgical procedures on 26 male mices The animals were randomized into three groups. In each group the muscular bed of sciatic nerve was burned with diathermocoagulator. In treated group we applied the tested gel in order to reduce the post surgical scar. After 3 weeks the strenght of the scar was studied using a specific tool. Also histologic analysis was performed. We also reported the results of CMC-PEO gel on 8 patients who underwent surgical decompression of peripheral nerves affected by recurrent compressive syndrome. The biomechanical analysis showed that gel application strongly reduces scar tissue. The difference between not treated and treated group was statistically significative. The histological analysis confirmed this data showing a cleavage plan between scar tissue and sciatic nerve. In patients we monitored VAS pre and post operative and we described reduction from 8 to 1 in 6 patients and from 6 to 1 in two patients. In conclusion, our study proves the efficacy in animal models of Dynavisc in scar tissue formation prevention and discloses the absolute security and biocompatibility of this products. Moreover also the small sample of patients showed the safety of this product on human, and proved its efficacy on recurrent nerve compression syndrome associated with neurolysis