An unusual injury pattern: arm wrestling injury, treatment modalities, clinical outcomes, and return to sport.

BACKGROUND: In the sport of arm wrestling, the great rotational force is applied to the upper extremity, which can result in muscle and tendon injuries in the shoulder, elbow, and wrist joints, and even bone fractures. The aim of this study was to present the treatment modalities, functional outcomes, and return to sport after arm wrestling injuries. METHODS: A retrospective evaluation was made of the trauma mechanisms, treatment modalities, clinical outcomes, and time of return to sports of patients admitted to our hospital with an arm wrestling injury between 2008 and 2020. At the final follow-up examination, the functional scores (DASH score and constant score) of the patients were evaluated. RESULTS: Evaluation was made of 22 patients comprising 18 (82%) males and 4 (18%) females with a mean age of 20±6.1 years (range, 12-33 years). Two (10%) patients were professional arm wrestlers. The DASH scores at the final follow-up (mean 4 years) examination were 0.57 (min: 0 and max: 1.7) for the patients with humerus shaft fracture. All the patients with isolated soft-tissue injuries returned to sports within 1 month. Patients with humeral shaft fractures returned to sports later and had a lower functional score (P<0.05). There was no disability in any patient during long-term follow-up. Patients with soft-tissue injuries continued arm wrestling more than patients with bone injuries (P<0.001). CONCLUSION: This study constitutes the largest patient series evaluating patients presenting at a health-care institution with any complaint after arm wrestling. Arm wrestling is not a sport that only results in bone pathologies. Therefore, providing the participants in this sport with information that they may be injured in arm wrestling but there will be a full recovery, may reassure and encourage them.

Electric Scooter-Related Upper Limb Fractures: Analysis of 458 Cases.

PURPOSE: To perform an analysis of electric scooter (e-scooter)-related upper limb fractures (ULFs), which have increased dramatically in parallel with the rapid rise in the use of e-scooters and shared e-scooter services in recent years. METHODS: We retrospectively reviewed the medical charts of e-scooter-related emergency department visits between January 2017 and January 2020 at a level I trauma center. All patients with ULFs were included in the study, and their data were analyzed for demographics, fracture diagnosis, associated injuries, and required surgical treatment. RESULTS: This study included 356 patients (50% men) with 458 ULFs, of which 23 (5%) were open fractures. The mean age of the cohort was 32.9 years (standard deviation, 10.1 years). The most common mechanism of injury was rider fall (92.1%). The nondominant hand was injured in 53.1% of cases, and 32.1% of all fractures were treated with surgery. A total of 120 (33.7%) patients sustained more than 1 ipsilateral ULF, and 27 (7.6%) patients had a concomitant contralateral ULF. Radial head fracture was the most common fracture type (n = 123, 26.8%), of which 16 (13%) were bilateral. The fifth ray was injured most frequently among the metacarpal and phalangeal fractures (n = 33, 47.1%). Most of the nonextremity-associated injuries were those of the head and maxillofacial bones. CONCLUSIONS: The most common ULF associated with e-scooters was the radial head fracture. Physicians should be alert to and seek associated fractures during initial assessments of e-scooter-related upper limb injuries. Further investigation may be warranted to evaluate the effectiveness of protective measures in reducing the number of injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Initial kinematic chain injuries increase hazard of subsequent arm injuries in professional baseball pitchers.

BACKGROUND: Currently, there are few studies that have evaluated the relationship between a lower extremity or trunk injury (kinematic chain) and subsequent arm injury. The purpose of this study was (1) to investigate the relationship between initial kinematic chain (lower extremity or trunk) injury and subsequent arm injury; and (2) to investigate the relationship between initial shoulder or elbow injury and subsequent arm injury. METHODS: A 7-year prospective injury risk study was conducted with Minor League Baseball pitchers. Pitches, pitching appearances, athlete exposures (AEs), and arm injuries (≥1-day time loss) were documented throughout the season. Cox survival analyses with 95% confidence intervals (95% CIs) were performed. Confounders controlled for included age, body mass index, arm dominance, pitching role, previous arm injury, number of pitching appearances, and seasonal pitch load. RESULTS: A total of 297 pitchers participated (total player days = 85,270). Arm injury incidence was 11.4 arm injuries/10,000 AEs, and kinematic chain incidence was 5.2 injuries/10,000 AEs. Pitchers who sustained a kinematic chain injury demonstrated a greater hazard (2.6 [95% CI: 1.2, 5.6], P = .019) of sustaining an arm injury. Pitchers who sustained an initial shoulder injury demonstrated a greater hazard (9.3 [95% CI: 1.1, 83], P = .047) of sustaining a subsequent shoulder or elbow injury compared with pitchers who sustained an initial elbow injury. CONCLUSIONS: Pitchers who sustained an initial lower extremity or trunk injury demonstrated an increased subsequent arm injury hazard compared with pitchers who did not. Pitchers who sustained an initial shoulder injury demonstrated a greater hazard of sustaining a subsequent arm injury compared with pitchers who sustained an initial elbow injury. However, this secondary analysis should be interpreted with caution. Clinicians should monitor risk with workload accumulation, which may be related to pitching compensatory strategies in a fatigued state. Pitchers who sustain a shoulder injury should be evaluated and perform both shoulder and elbow rehabilitation strategies before return to sport.

Frequency of Adverse Events in the Placebo Arms of COVID-19 Vaccine Trials: A Systematic Review and Meta-analysis.

Importance: Adverse events (AEs) after placebo treatment are common in randomized clinical drug trials. Systematic evidence regarding these nocebo responses in vaccine trials is important for COVID-19 vaccination worldwide especially because concern about AEs is reported to be a reason for vaccination hesitancy. Objective: To compare the frequencies of AEs reported in the placebo groups of COVID-19 vaccine trials with those reported in the vaccine groups. Data Sources: For this systematic review and meta-analysis, the Medline (PubMed) and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched systematically using medical subheading terms and free-text keywords for trials of COVID-19 vaccines published up to July 14, 2021. Study Selection: Randomized clinical trials of COVID-19 vaccines that investigated adults aged 16 years or older were selected if they assessed solicited AEs within 7 days of injection, included an inert placebo arm, and provided AE reports for both the vaccine and placebo groups separately. Full texts were reviewed for eligibility by 2 independent reviewers. Data Extraction and Synthesis: Data extraction and quality assessment were performed independently by 2 reviewers, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline and using the Cochrane risk-of-bias tool. Meta-analyses were based on random-effects models. Main Outcomes and Measures: The primary outcomes were the proportions of placebo recipients reporting overall, systemic, and local (injection-site) AEs as well as logarithmic odds ratios (ORs) to evaluate group differences. Outcomes were tested for significance using z tests with 95% CIs. Results: Twelve articles with AE reports for 45 380 participants (22 578 placebo recipients and 22 802 vaccine recipients) were analyzed. After the first dose, 35.2% (95% CI, 26.7%-43.7%) of placebo recipients experienced systemic AEs, with headache (19.3%; 95% CI, 13.6%-25.1%) and fatigue (16.7%; 95% CI, 9.8%-23.6%) being most common. After the second dose, 31.8% (95% CI, 28.7%-35.0%) of placebo recipients reported systemic AEs. The ratio between placebo and vaccine arms showed that nocebo responses accounted for 76.0% of systemic AEs after the first COVID-19 vaccine dose and for 51.8% after the second dose. Significantly more vaccine recipients reported AEs, but the group difference for systemic AEs was small after the first dose (OR, -0.47; 95% CI, -0.54 to -0.40; P < .001; standardized mean difference, -0.26; 95% CI, -0.30 to -0.22) and large after the second dose (OR, -1.36; 95% CI, -1.86 to -0.86; P < .001; standardized mean difference, -0.75; 95% CI, -1.03 to -0.47). Conclusions and Relevance: In this systematic review and meta-analysis, significantly more AEs were reported in vaccine groups compared with placebo groups, but the rates of reported AEs in the placebo arms were still substantial. Public vaccination programs should consider these high rates of AEs in placebo arms.

Acute distal biceps tendon rupture: retrospective analysis of two different approaches and fixation techniques.

PURPOSE: The aim of our study is to compare the modified double incision (DI) with bone tunnel reinsertion with the single-incision (SI) double tension slide technique in terms of clinical and functional outcomes and complication rates. METHODS: A retrospective comparative analysis was performed on 65 patients treated for total distal biceps tendon rupture. The surgical technique adopted for each patient was based on the preference of two experienced elbow surgeons. The DASH and MAYO questionnaires, functional outcome and ROM were recorded in all subjects. RESULTS: Of 65 patients, we collected data of a cohort of 54 distal biceps tendon ruptures that satisfied inclusion criteria. Twenty-five were treated by modified DI and 29 SI techniques. The recovery of the complete ROM in terms of flexion/extension and prono-supination occurred in the 79.6% of the patients, without statistical significant difference between the adopted technique. We reported a complication rate of 12% and 20.7% for DI and SI techniques, respectively, without statistical correlation (P = 0.84). The average DASH score was similar for DI and SI techniques without significant differences (P = 0,848). The Mayo score results were excellent in the majority of the patients. No significant difference in MAYO results was reported comparing the surgical techniques (P = 1). CONCLUSION: Both techniques provide a reliable and strong repair with an optimal recovery of ROM returning to preinjury activity with substantially overlapping timelines.

The effect of COVID-19 on a Major Trauma Network. An analysis of mechanism of injury pattern, referral load and operative case-mix.

PURPOSE: The aim of this study was to evaluate changes in both mechanism and diagnoses of injuries presenting to the orthopaedic department during this lockdown period, as well as to observe any changes in operative case-mix during this time. METHODS: A study period of twelve weeks following the introduction of the nationwide "lockdown period", March 23rd - June 14th, 2020 was identified and compared to the same time period in 2019 as a "baseline period". A retrospective analysis of all emergency orthopaedic referrals and surgical procedures performed during these time frames was undertaken. All data was collected and screened using the 'eTrauma' management platform (Open Medical, UK). The study included data from a five NHS Foundation Trusts within North West London. A total of 6695 referrals were included for analysis. RESULTS: The total number of referrals received during the lockdown period fell by 35.3% (n=2631) compared to the same period in 2019 (n=4064). Falls remained proportionally the most common mechanism of injury across all age groups in both time periods. The proportion sports related injuries compared to the overall number of injuries fell significantly during the lockdown period (p<0.001), however, the proportion of pushbike related accidents increased significantly (p<0.001). The total number of operations performed during the lockdown period fell by 38.8% (n=1046) during lockdown (n=1732). The proportion of patients undergoing operative intervention for Neck of Femur (NOF) and ankle fractures remained similar during both study periods. A more non-operative approach was seen in the management of wrist fractures, with 41.4% of injuries undergoing an operation during the lockdown period compared to 58.6% at baseline (p<0.001). CONCLUSION: In conclusion, the nationwide lockdown has led to a decrease in emergency orthopaedic referrals and procedure numbers. There has been a change in mechanism of injuries, with fewer sporting injuries, conversely, there has been an increase in the number of pushbike or scooter related injuries during the lockdown period. NOF fractures remained at similar levels to the previous year. There was a change in strategy for managing distal radius fractures with more fractures being treated non-operatively.

Surgical Treatment of Upper Extremity Gunshot Injures: An Updated Review.

INTRODUCTION: Firearm morbidity and mortality have been increasing in recent years, and with this, the demand for medical personnel firearm injury treatment knowledge. Extremities contribute to a majority of firearm injuries, with these injuries being particularly complex because of neurovascular proximity within a confined space. Knowledge of firearm mechanism of injury and treatment management options is important for any trauma hand surgeon. Many factors play vital roles in the treatment of complex upper extremity (UE) gunshot wounds (GSWs). The aim of our review and case illustrations is to provide hand surgeons with an up-to-date guide for initial emergent management, soft tissue, bony, and nerve repair and reconstruction. PATIENT AND METHODS: A literature review was conducted in the current management of UE GSW injuries, and 2 specific patient case examples were included. High-energy versus low-energy GSWs were documented and compared, as well as containment injures. Management including soft tissue, bony, and nerve injuries was explored along with patient outcome. Based on these findings, guidelines for GSW management were purposed. CONCLUSION: Gunshot wounds of the UE encompass a group of highly heterogeneous injuries. High-energy wounds are more extensive, and concomitant injuries to bone, vessel, nerve, muscle, and soft tissue are common. Early treatment with adequate debridement, skeletal fixation, and soft tissue coverage is indicated for complex injuries, and antibiotic treatment in the pre-, peri-, and postoperative period is indicated for operative injuries. Soft tissue coverage options include the entire reconstructive ladder, with pattern of injury and considerations of wound characteristics dictating reconstructive choice. There are arguments to using either external or internal bony fixation techniques for bone fracture management, with choice tailored to the patient. For management of nerve injuries, we advocate earlier nerve repair and a shorter duration of observation before secondary reconstruction in selective cases. If transected nerve endings cannot be brought together, nerve autografts of shorter length are recommended to bridge nerve ending gaps. A significant number of patients with GSW fail to make necessary follow-up appointments, which adds to challenges in treatment.

A small number of daily pitches induces shoulder and elbow injuries among high school baseball pitchers: a prospective study.

Baseball players frequently injure their shoulders and elbows. Preseason risk factors for such injuries have been relatively well studied, but in-season risk factors are less known, and the relationship between the number of pitches and the incidence of such injuries in baseball pitchers of any level is unclear. Identifying the risk factors related to the number of daily pitches is particularly important to prevent baseball-related arm injuries among young pitchers. Thus, we prospectively investigated the relationship between the number of daily full-power pitches in high school baseball pitchers and the incidence of shoulder and elbow injuries. We observed that a small number of daily full-power pitches, < 30 pitches per day, in high school baseball pitchers, significantly increased the risk of shoulder and elbow injuries: these players had a 2.3-times greater risk of injuries and a 45-day earlier occurrence of injuries than those pitching ≥ 30 pitches per day. Although unexpected, this was plausible as continuous daily pitching is required to maintain physical condition in growing and maturing high school pitchers. These findings may form the basis for establishing guidelines regarding the appropriate number of daily pitches required to prevent shoulder and elbow injuries in high school baseball pitchers.

The Weekend Warrior: Common Hand and Wrist Injuries in Athletes.

Weekend warriors are individuals who condense their weekly physical activity into extended intervals over one or two days.1 Excessive physical activity can result in a multitude of overuse and traumatic upper extremity injuries. The purpose of this review is to highlight the etiology and management of the more common hand and wrist injuries in athletes.

Does humeral torsion play a role in shoulder and elbow injury profiles of overhead athletes: a systematic review.

BACKGROUND: Humeral retrotorsion (HRT) is one bony adaptation that occurs in overhead athletes. This bony adaptation often leads to bilateral changes in range of motion at the glenohumeral joint. Because HRT can create different stress environments on the surrounding tissue, it may play a role in upper-limb injury and pain profiles. Therefore, the aim of this review was to examine whether HRT plays a role in shoulder and elbow injury profiles. METHODS: Two separate critical appraisal tools were administered: the Newcastle-Ottawa Scale (case control) and the Appraisal Tool for Cross-sectional Studies. The primary author extracted all data and obtained means and standard deviations for each outcome. Cohen d effect sizes (ESs) were calculated (ES [95% confidence interval]) for all HRT measurements including nondominant, dominant, and side-to-side differences. Finally, the Strength of Recommendation Taxonomy was used to evaluate the overall strength of the recommendation. RESULTS: Nine articles were included in this review. Large ESs were present in 2 studies on examination of symptomatic and asymptomatic dominant HRT and ranged between 0.83 (0.08-1.55) and -2.57 (-3.66 to 1.99). The majority of all ESs for all HRT measurements were moderate or low, rendering comparisons between asymptomatic and symptomatic cohorts that were not clinically meaningful. CONCLUSION: The Strength of Recommendation Taxonomy rating was C based on inconsistent findings. Differences in sports populations and definitions of injuries across studies may be one reason for the varying ESs. HRT does occur in the overhead population, but the degree to which this HRT starts to affect upper-limb injury is unknown and is more than likely player specific and multifactorial.

Sport Specialization and Increased Injury Frequency in Youth Baseball Players: A Prospective Study.

CONTEXT: Sport specialization is thought to be a primary contributor to the throwing-related injury risk in youth baseball players. OBJECTIVE: To (1) establish arm-injury incidence in a cohort of male youth (9-12 years old) baseball players and (2) examine sport specialization and the frequency of arm injuries in the same cohort. DESIGN: Cohort study. SETTING: Greenville, South Carolina, youth baseball programs and tournaments. PATIENTS OR OTHER PARTICIPANTS: A total of 159 asymptomatic youth baseball players (age = 11.1 ± 1.1 years) were physically assessed and then were prospectively followed for 6.7 ± 1.5 months. MAIN OUTCOME MEASURE(S): Athlete demographics and playing and injury histories were initially recorded. Athlete-exposures and presence of arm injury were prospectively tracked. All injuries were physically confirmed by a licensed physical therapist. RESULTS: Youth players demonstrated an arm-injury incidence rate of 2.22 per 1000 athlete-exposures. Parents and players underestimated sport-specialization status based on the standard research definition (self versus research based: 31% versus 83%, respectively; P = .001). The frequency of arm injuries was higher in specialized players (100%) than in nonspecialized players (80%, P = .03) but did not differ between pitchers and position players (13.2% each, P = 1.00). CONCLUSIONS: Sport specialization was associated with throwing-related arm injuries in a small cohort of youth baseball players. It is concerning that 57.9% of parents and specialized players were unaware of the athletes' status. Larger studies with longer follow-up periods are needed to further evaluate injury-risk profiles in physically developing youth populations.

Playground-related Extremity Fractures in an Asian Setting over the Last Decade - Are We Safe?

The cost of playground-related injuries remains significant. Measures adopted to prevent such fractures or reduce their severity would translate into appreciable financial savings. Our study looks at the changes in playground-related extremity fracture epidemiology over the past decade after the implementation of latest playground standards. This is a retrospective case series approved by the local ethics board comparing the results of two descriptive studies; one conducted prior to the implementation of the Singapore Productivity and Standards Board Singapore Standards SS 457: 2007 and the other thereafter. The demographics have remained the same. The proportion of public playground injuries has fallen significantly from 89.6% to 76.3% (p < 0.05), whereas school playground injuries have risen from 5.9% to 18.0% (p < 0.05). Fractures related to monkey bars and the flying fox have shown a significant improvement, decreasing to 38.1% from 47.6% (p < 0.05) and 1% from 6.9% (p < 0.05), respectively. There has been a decrease of 33% in playground-related injuries. The total financial cost of sustaining one playground-related extremity fracture has generally increased by 50%. However, considering the 37.4% drop in surgeries, the actual overall costs to the healthcare system have essentially fallen. Safety standards have had a positive effect on playground safety in Singapore. There are now fewer and less severe playground-related extremity fractures.

Upper extremity disability and quality of life after breast cancer treatment in the Greater Plains Collaborative clinical research network.

PURPOSE: Chronic upper extremity disability (UED) is common after breast cancer treatment but under-identified and under-treated. Although UED has been linked to quality of life (QoL), the role of UED as mediator between contemporary treatment practices and QoL has not been quantified. This investigation describes UED in a contemporary sample of breast cancer patients and examines its relationship with personal and treatment factors and QoL. METHODS: Eight hundred and thirty-three women diagnosed at eight medical institutions during 2013-2014 with microscopically confirmed ductal carcinoma in situ or invasive stage I-III breast cancer were surveyed an average of 22 months after diagnosis. UED was measured with a modified QuickDASH and QoL with the FACT-B. The questionnaire also collected treatments, sociodemographic information, comorbidity, body mass index, and a 3-item health literacy screener. RESULTS: Women who received post-mastectomy radiation and chemotherapy experienced significantly worse UED and QoL. Women who had lower income, lower health literacy and prior diabetes, arthritis or shoulder diagnoses had worse UED. Patients with worse UED reported significantly worse QoL. Income and health literacy were independently associated with QoL after adjustment for UED but treatment and prior conditions were not, indicating mediation by UED. UED mediated 52-79% of the effect of mastectomy-based treatments on QoL as compared with unilateral mastectomy without radiation. UED and QoL did not differ by type of axillary surgery or post-mastectomy reconstruction. CONCLUSIONS: A large portion of treatment effect on QoL is mediated by UED. Rehabilitation practices that prevent and alleviate UED are likely to improve QoL for breast cancer survivors.

Secretan's syndrome: case report.

Secretan's syndrome is a rare clinical condition with recurrent swelling of the forearm and dorsum of the hand, together with flexion contracture of the fingers and a thumb that is spared. The disease is associated with automutilation. We present a typical case of a 42-year old women with Secretan's syndrome.

Associations between upper extremity injury patterns in side impact motor vehicle collisions with occupant and crash characteristics.

INTRODUCTION: Side impact motor vehicle collisions (MVC) represent a significant burden of mortality and morbidity caused by automotive injury within the United States. The objective of this study was to evaluate the relationship between upper extremity (UE) injury patterns and contact sources in side impact MVC with occupant and crash variables. METHODS: Crash Injury Research and Engineering Network data obtained from 1998 to 2012 were used to evaluate UE injuries in side impact crashes. First row drivers and passengers that were at least 16 years old with complete crash information were included. Side impact crashes were defined to have an area of deformation to the side of the vehicle and a principal direction of force between 60° and 120° or 240° and 300°. Injuries were stratified by type, anatomic location, and Abbreviated Injury Scale (AIS) severity. Occupant variables included age, sex, height, weight, body mass index, and Injury Severity Score. Vehicle and crash variables included in the analysis were change in vehicle velocity at the time of impact, maximum door intrusion, maximum B-pillar intrusion, seat track position, belt use, vehicle type, impact type, and injury source. Statistical analysis of the UE injury data included descriptive statistics, linear regression analyses with occupant variables, and logistic regression analyses with vehicle and crash variables. RESULTS: There were 903 UE injuries among 408 case occupants. The most common injury type was soft tissue injury (72.5%). The majority of fractures were proximal to and including the humerus (70.3%) with the clavicle being the most common fracture location (N = 89). AIS 2+ UE injuries were associated with a significantly higher mean occupant Injury Severity Score than AIS 1 UE injuries (p = 0.01). Contact with the door was the leading cause of UE injury (34.2%). The odds (OR [95% confidence interval], p-value) of an AIS 2+ UE injury due to contact with the B-pillar (5.3 [3.1, 9.1], <0.0001), door (1.9 [1.3, 2.7], 0.0006), and steering wheel/assembly (2.7 [1.1, 6.3], 0.03) were significantly higher than all other injury sources combined. Scapula fractures were significantly associated with rearward seat track positions (1.46 [1.04, 2.05], 0.03). CONCLUSIONS: This study provides insight into UE injury patterns in side impact MVC. The clavicle was the most common UE fracture location. Contact with the door resulted in the highest number of UE injuries and the B-pillar resulted in the most severe injuries. Additionally, exposure to greater B-pillar intrusion was associated with increased odds of scapula and clavicle fractures in side impacts.

[Free flaps use in chronic wounds: Retrospective study about 91 cases]. / Utilisation des lambeaux libres dans la prise en charge des plaies chroniques.

INTRODUCTION: Chronic wounds represent a major health challenge with no current standardized surgical treatment. The use of free flaps is little discussed in the literature, with a supposed propensity to failure given unfavorable local conditions and land often debility. We present here the analysis of our monocentric experience of the use of free flaps in the curative treatment of chronic wounds. PATIENTS ET METHODS: We performed a retrospective monocentric study over 18 years of all free flaps used for the treatment of a chronic wound between January 2001 and September 2016. Several criteria were evaluated on patients, wounds, free flaps used and immediate to late outcomes. RESULTS: Ninety-one patients were included (sex ratio M/F: 3.55) with an average age of 41.6±16 years. Wounds were localized to the leg in 92.3% of cases and 58% of patients had initial osteomyelitis. The flaps used were predominantly muscle flaps (61.6%). The flaps survival rate was 92.3%. With a mean follow-up of 50 months, the reconstructive failure rate was 20.9%. The presence of a chronic osteomyelitis is the only statistically significant factor of reconstruction failure (P=0.0169) with a risk of failure multiplied by 5. CONCLUSION: Our study demonstrates that the reliability of free flaps in the treatment of chronic wounds is comparable, regardless of the time since the initial cutaneous lesion, to that existing in the treatment of acute wounds or in the reconstruction after oncological excision. The presence of a chronic osteomyelitis, however, represents a major risk of reconstruction failure by increasing 5 times the risk of failure. Recent changes in the integumentary reconstruction paradigm of the lower limb will undoubtedly allow in the next few years to establish more rationally the place of muscle free flaps in the therapeutic armamentarium of chronic wounds.