Do one-time intracompartmental pressure measurements have a high false-positive rate in diagnosing compartment syndrome?

Quantitative diagnosis of early acute compartment syndrome using two-dimensional shear wave elastography in a rabbit model

PURPOSE

This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS.

METHODS

An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury.

RESULTS

The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis.

CONCLUSION

In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Trimodal wireless intramuscular device detects muscle pressure, flow, and oxygenation changes in porcine model of lower extremity compartment syndrome

PURPOSE

Compartment syndrome remains difficult to diagnose early in its clinical course. Pressure transducer catheters have been used to directly measure intracompartmental pressure (ICP), but this method is unreliable, with a false positive rate of 35%. We have previously used intramuscular near infrared spectroscopy to detect changes in tissue oxygen saturation (StO2) in response to increasing ICP using a novel implantable probe. However, measuring StO2 may not be sufficient to identify CS in the clinical setting. The pathophysiology of CS consists of increased ICP, leading to decreased tissue perfusion, and resulting in reduced tissue oxygenation. More clinically useful information may come from the integration of multiple data streams to aid in the diagnosis of CS. In this study, we present a novel, intramuscular probe capable of simultaneous measurement of ICP, StO2, and microvascular blood flow in a porcine model of ACS.

METHODS

Proof of concept for this device is demonstrated in a porcine lower extremity balloon compression model of ACS. Pressure was maintained for 20 min (short-term) or 3 h (long-term) before the balloon volume was removed.

RESULTS

In both short- and long-term experiments, as ICP increased with increasing balloon volume, the novel multimodal sensor simultaneously and reliably detected pressure elevation and corresponding reversible reductions in microvascular flow rate and tissue oxygenation.

CONCLUSION

This novel trimodal device simultaneously measured the elevated ICP, decreased perfusion, and tissue ischemia of evolving ACS, substantiating our basic understanding of CS pathophysiology.

Comparison of single and double incision leg fasciotomy in disaster settings-Experience from 2023 Türkiye earthquakes

INTRODUCTION

Although there are studies comparing methods for leg fasciotomy in compartment syndrome after fractures, choice of single or double fasciotomies in disasters was not investigated. The aim of this study was to compare the efficacy of single and double incision leg fasciotomy in the setting of disaster.

METHODS

Patients that have undergone fasciotomy after 2023 Kahramanmaraş earthquakes were retrospectively analyzed. The cases were separated into two groups as single incision and double incision according to the method of the first fasciotomy. The number of debridements after each fasciotomy, muscle group excisions, completion time of treatment, presence of amputation, the method of closure (primary closure or graft/flap) and positive results of wound cultures were analyzed and compared between two groups.

RESULTS

62 legs of 52 patients (22 females, 30 males, age 36.9 ± 11.2 years) with compartment syndrome that have undergone fasciotomy after 2023 Kahramanmaraş earthquakes were included in the study. Single-incision group included 27 legs and double incision group included 35 legs. Amputation was needed in 15 patients (%24.2), six in single incision group and nine in double incision group. (p = 0.75). Compartment excision (eight patients in single incision, nine patients in double incision groups, p = 0.81), number of debridements (median 4 in both groups, p = 0.55), wound closure time (median 17 days in single incision, 22 days in double incision groups, p = 0.52), graft or flap requirement (11 patients in single incision, 16 patients in double incision groups, p = 0.53), positive culture results (15 patients in single incision, 16 patients in double incision groups, p = 0.44) were not different statistically between two groups.

CONCLUSION

Single and double incision fasciotomy methods are equally effective and safe in treatment of compartment syndrome of the leg in disaster situations. To our knowledge, this is the first study comparing outcomes of single and double incision fasciotomy in disaster settings.

Traumatic Rhabdomyolysis: Crush Syndrome, Compartment Syndrome, and the 'Found Down' Patient

Traumatic rhabdomyolysis is a systemic manifestation of muscle injury and can occur from various traumatic etiologies, including crush syndrome (CrshS) and compartment syndrome (CS). Although historically described in natural disaster survivors trapped under collapsed structures, the frequency of CrshS has increased in the setting of 'found down' patients from opioid overdoses. Signs and symptoms of the injured limb in CrshS may range from pressure-induced skin changes to neurologic deficits and paralysis. Although its pathophysiology differs from CS, severe injuries may lead to an associated CS. Identifying CS in a patient with CrshS can be difficult but is important to distinguish because it affects treatment. The degree of muscle damage, viability of the remaining muscular compartment, and presence of elevated compartment pressures dictate the need for surgical intervention in the form of fasciotomy. Surgical outcomes from CrshS and delayed CS result in similar high morbidity and surgical complications. This review defines and classifies the types of traumatic rhabdomyolysis and summarizes the outcomes to facilitate timely diagnosis and appropriate management for this population to reduce morbidity associated with these conditions.

A practical nomogram for predicting amputation rates in acute compartment syndrome patients based on clinical factors and biochemical blood markers

BACKGROUND

Amputation is a serious complication of acute compartment syndrome (ACS), and predicting the risk factors associated with amputation remains a challenge for surgeons. The aim of this study was to analyze the risk factors for amputation in patients with ACS and develop a nomogram to predict amputation risk more accurately.

METHODS

The study population consisted of 143 patients (32 in the amputation group and 111 in the limb preservation group) diagnosed with ACS. LASSO and multivariate logistic regression were used to screen predictors and create a nomogram. The model's accuracy was assessed by receiver operating characteristic (ROC) curves, C-index, calibration curves, and decision curve analysis (DCA).

RESULTS

The predictors included cause of injury, vascular damage, shock, and fibrinogen in the nomogram. The C-index of the model was 0.872 (95% confidence interval: 0.854-0.962), and the C-index calculated by internal validation was 0.838. The nomogram's area under the curve (AUC) was 0.849, and the calibration curve demonstrated a high degree of agreement between the nomogram's predictions and actual observations. Additionally, the DCA indicated good clinical utility for the nomogram.

CONCLUSION

The risk of amputation in ACS patients is associated with the cause of injury, vascular damage, shock, and fibrinogen. Our nomogram integrating clinical factors and biochemical blood markers enables doctors to more conveniently predict the risk of amputation in patients with ACS.

Percutaneously introduced wireless intramuscular near-infrared spectroscopy device detects muscle oxygenation changes in porcine model of lower extremity compartment syndrome

Serial examination and direct measurement of intracompartmental pressure (ICP) are suboptimal strategies for the detection of acute compartment syndrome (CS) because they are operator-dependent and yield information that only indirectly reflects intracompartmental muscle perfusion. As a result, instances of unnecessary fasciotomy and unrecognized CS are relatively common. Recently, near-infrared spectroscopy (NIRS)-based systems for compartment monitoring have generated interest as an adjunct tool. Under ideal conditions, NIRS directly measures the oxygenation of intracompartmental muscle (StO₂ ), thereby obviating the challenges of interpreting equivocal clinical examination or ICP data. Despite these potential advantages, existing NIRS sensors are plagued by technical difficulties that limit clinical utility. Most of these limitations relate to their transcutaneous design that makes them susceptible to both interference from intervening skin/subcutaneous tissue, underlying hematoma, and instability of the skin-sensor interface. Here, we present a flexible, wireless, Bluetooth-enabled, percutaneously introducible intramuscular NIRS device that directly and continuously measures the StO₂ of intracompartmental muscle. Proof of concept for this device is demonstrated in a swine lower extremity balloon compression model of acute CS, wherein we simultaneously track muscle oxygenation, ICP, and compartment perfusion pressure (PP). The observed StO₂ decreased with increasing ICP and decreasing PP and then recovered following pressure reduction. The mean change in StO₂ as the PP was decreased from baseline to 30 mmHg was -7.6%. The mean difference between baseline and nadir StO₂ was -17.4%. Cross-correlations (absolute value) describing the correspondence between StO₂ and ICP were >0.73. This novel intramuscular NIRS device identifies decreased muscle perfusion in the setting of evolving CS.

Well leg compartment syndrome due to the lithotomy position in orthopedic surgery: a report of two cases and a review of the literature

The well leg compartment syndrome (WLCS) is a complication that can occur because of the lithotomy surgical position. Although it is a very rare entity, it can lead to a permanent disability if not properly treated. Very few cases have been described in the literature as a result of orthopedic surgery. We present two cases of WLCS that developed because of the lithotomy position. The first case concerns a patient who sustained a left floating knee and developed a compartment syndrome of the right uninjured calf during surgery. A good outcome has been achieved after early fasciotomies. The second case is about a patient who developed a compartment syndrome of the right buttock after a left unicompartmental knee replacement. This patient was treated conservatively because of delayed diagnosis. A brief literature review regarding the WLCS in orthopedic surgery is also conducted.

Defining Incidence of Acute Compartment Syndrome in the Research Setting: A Proposed Method From the PACS Study

OBJECTIVE

To compare the retrospective decision of an expert panel who assessed likelihood of acute compartment syndrome (ACS) in a patient with a high-risk tibia fracture with decision to perform fasciotomy.

DESIGN

Prospective observational study.

SETTING

Seven Level 1 trauma centers.

PATIENTS/PARTICIPANTS

One hundred eighty-two adults with severe tibia fractures.

MAIN OUTCOME MEASUREMENTS

Diagnostic performance (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver-operator curve) of an expert panel's assessment of likelihood ACS compared with fasciotomy as the reference diagnostic standard.

SECONDARY OUTCOMES

The interrater reliability of the expert panel as measured by the Krippendorff alpha. Expert panel consensus was determined using the percent of panelists in the majority group of low (expert panel likelihood of ≤0.3), uncertain (0.3-0.7), or high (>0.7) likelihood of ACS.

RESULTS

Comparing fasciotomy (the diagnostic standard) and the expert panel's assessment as the diagnostic classification (test), the expert panel's determination of uncertain or high likelihood of ACS (threshold >0.3) had a sensitivity of 0.90 (0.70, 0.99), specificity of 0.95 (0.90, 0.98), PPV of 0.70 (0.50, 0.86), and NPV of 0.99 (0.95, 1.00). When a threshold of >0.7 was set as a positive diagnosis, the expert panel assessment had a sensitivity of 0.67 (0.43, 0.85), specificity of 0.98 (0.95, 1.00), PPV of 0.82 (0.57, 0.96), and NPV of 0.96 (0.91, 0.98).

CONCLUSION

In our study, the retrospective assessment of an expert panel of the likelihood of ACS has good specificity and excellent NPV for fasciotomy, but only low-to-moderate sensitivity and PPV. The discordance between the expert panel-assessed likelihood of ACS and the decision to perform fasciotomy suggests that concern regarding potential diagnostic bias in studies of ACS is warranted.

LEVEL OF EVIDENCE

Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

The Role of the Ilizarov Ring External Fixator in the Management of Tibial Fractures with Impending/Incomplete Compartment Syndrome

Objective  The management of tibia fractures complicated by compartment syndrome affects the treatment and functional outcome of patients due to the complications associated with fasciotomy. The purpose of the present study is to differentiate impending/incomplete compartment syndrome (ICS) from established acute compartment syndrome (ACS) in tibial fractures, and to assess the outcome of the fixation of the Ilizarov apparatus in patients with these fractures presenting with ICS, who were not submitted to fasciotomy.

Methods  After the establishment of the inclusion and exclusion criteria, 19 patients were included in the study from January 2007 to December 2017. All patients were male, with an average age of 42.3 ± 11.38 years. All of these patients were managed with Ilizarov ring fixation as per the medical and surgical protocol established in the present study.

Results  The average follow-up obtained for our 18 patients was of 47 ± 41.5 months, with one patient being lost to follow-up. The average time for ring application was of 3.7 ± 1.7 days. In total, 3 (16.7%) of these patients had nonunion. There were no soft-tissue or neurovascular complications in the immediate postoperative period. All of the patients eventually united and were independently mobile without any sequelae of compartment syndrome.

Conclusion  The Ilizarov ring external fixator can be used in the management of tibial fractures with ICS, avoiding fasciotomy with its various complications of infection and nonunion, resulting in fewer surgeries and faster rehabilitation. Surgeons should carefully differentiate ACS and ICS in these patients, as the clinical and functional results vary significantly. Unnecessary fasciotomies should be avoided.

A dual-sensor ultrasound based method for detecting elevated muscle compartment pressures: A prospective clinical pilot study

BACKGROUND

Acute compartment syndrome (ACS) is a limb-threatening condition associated with elevated muscle compartment pressures (MCPs). The only existing treatment of ACS is to reduce MCP by fasciotomy; however, a reliable clinical method for detecting elevated MCPs is lacking. A dual-sensor (ultrasound and pressure) technology to detect elevated MCPs was previously tested on cadavers. Our goal was to examine the use of this technology in the clinical setting.

METHODS

Patients with tibia fractures were prospectively enrolled. Observers used a dual-sensor probe to measure the amount of pressure required to flatten the anterior compartment fascia (CFFP). Direct-MCP measurements and 4-compartment fasciotomy were done for suspected ACS.

RESULTS

Fifty-two patients were enrolled into the study. Nine patients underwent fasciotomy for a clinical diagnosis of ACS. Both CFFP (p-value = 8.395e-08) and delta-CFFP (p-value = 4.114e-05) were significantly larger in the fasciotomy group compared to the non-fasciotomy group. CFFP measurements showed very strong correlations to the direct MCP measurements (p-value = 0.006746, rho = 0.9285714), and delta-CFFP showed strong correlation (p-value = 0.06627, rho = 0.75). CFFP measurements had good inter-observer variability, with an interclass correlation (ICC) of 0.814 (95%-Confidence Interval: 0.631-0.907) and excellent intra-observer variability with an ICC of 0.942 (95%-Confidence Interval: 0.921-0.958).

CONCLUSION

The results of this pilot study suggest that the proposed ultrasound-based method is useful in detecting elevated MCPs and may be helpful in the diagnosing ACS or ruling out the need for urgent fasciotomy. Large-scale clinical trials are needed to validate these claims.

'Well-leg' compartment syndrome associated with gynaecological surgery: a perioperative risk-reduction protocol and checklist

'Well-leg' compartment syndrome (WLCS) is an uncommon, but potentially devastating, complication associated with prolonged patient positioning for abdomino-pelvic surgery. Gynaecologists, anaesthetists and the wider theatre team share a responsibility to minimise the risk of this highly morbid, and even fatal, postoperative complication. This article provides an overview of WLCS related to gynaecological surgery - raising awareness amongst gynaecologists and highlighting the time-critical nature of diagnosis and management. Given the potential litiginous nature of this complication, we also present a perioperative checklist and risk-reduction protocol to suggest a standardised approach to prevention and relevant documentation. TWEETABLE ABSTRACT: Gynaecologists share a responsibility to minimise the risk of postoperative 'well-leg' compartment syndrome.

Acute compartment syndrome caused by hematoma after shoulder surgery: a case series

BACKGROUND

The development of acute compartment syndrome (ACS) of the upper extremity after an elective surgical shoulder procedure is rare but can have devastating results. We describe a series of patients who developed ACS of the upper extremity caused by hematoma formation and subsequent upper extremity swelling after undergoing elective surgical shoulder procedures.

METHODS

We retrospectively reviewed the database of our tertiary care institution between 2004 and 2019 to find patients who developed ACS after elective shoulder surgery. We found 4 such patients and reviewed their medical records and extracted data on their history, clinical examination, predisposing factors, treatment, and clinical and radiographic outcomes.

RESULTS

Of the 4 patients treated, 2 had undergone reverse total shoulder arthroplasty, 1 had undergone open biceps tenodesis, and 1 had undergone closed manipulation for adhesive capsulitis. Two patients developed symptoms of ACS within 24 hours of the index procedure. Both were treated with immediate decompression of the hematoma, and both experienced complete pain relief and full recovery of function at 1-year follow-up. Two patients were on anticoagulation therapy. Of these, 1 patient developed ACS symptoms 14 days after a revision reverse total shoulder arthroplasty and was treated successfully with compartment release. Despite treatment, the other patient developed extensive necrosis of muscles and nerves in the upper extremity and severe neurologic deficits in hand and forearm function.

CONCLUSION

ACS of the upper extremity caused by hematoma formation can lead to catastrophic outcomes if diagnosis and treatment are not immediate. Providers should be aware of ACS and the need for prompt diagnosis and treatment.

Acute compartment syndrome (ACS) - a case of delayed diagnosis

Acute Compartment Syndrome (ACS) is a potential limb and life-threatening complication following trauma. ACS is characterised by increased pressure within a defined fascial compartment which diminishes perfusion pressure, leading to local tissue ischaemia. Timely diagnosis of ACS is crucial to prevent serious complications or irreversible damage which may lead to amputation or death. Even though the most common aetiology for ACS is major trauma, routine examination for ACS is rarely ennforced in patients with minor trauma or soft-tissue injuries which puts patients at risk of a detrimental delay in treatment. Trauma nurses and other clinicians should therefore avoid relying solely on specific clinical presentations to detect or suspect the development of ACS. This paper will present a case of ACS with an unusual presentation, and critically evaluate the diagnostic challenges of ACS in atypical presentations.

Iatrogenic Compartment Syndrome After Delayed Primary Closure of the Tibial Fracture-Related Leg Fasciotomy Wound: A Case Report

CASE

Compartment syndrome can occur after tibial fracture and requires prompt diagnosis and immediate fasciotomy. Because of post-traumatic swelling, delayed primary wound closure can be difficult requiring significant tension on the skin. Closing the skin in this setting theoretically puts the patient at risk of elevated compartment pressures, although compartment syndrome has never been reported in these circumstances. We describe a case of compartment syndrome that developed after delayed primary skin closure of a single incision 4-compartment fasciotomy wound after tibial fracture.

CONCLUSION

This is the first published description of compartment syndrome after delayed primary closure of a leg fasciotomy wound.

Compartment Syndrome: Evaluation of Skeletal Muscle Ischemia and Physiologic Biomarkers in Controlled Conditions Within Ex Vivo Isolated Muscle Bundles

OBJECTIVES

To identify potential physiologic markers of muscle ischemia to serve as diagnostic indicators of compartment syndrome. We hypothesize that muscle bundles in hypoxic conditions will elicit decreases in potential hydrogen (pH) and increases in lactate and potassium that correlates with decreased muscle twitch forces.

METHODS

We performed an ex vivo evaluation of individual skeletal muscle bundles obtained from a swine's diaphragm that were exposed to hypoxic conditions and compared with control groups. Over a 4-hour period, we evaluated the following parameters for each muscle bundle: muscle twitch forces and levels of potassium, lactate, and pH. Comparisons between the hypoxic and control groups were calculated at each time point using the 2-tailed Wilcoxon rank sum test for nonparametric data. Longitudinal associations between biomarkers and muscle twitch forces were tested using repeated measures analyses.

RESULTS

The hypoxic group elicited more significant decreases in normalized muscle twitch forces than the control group at all time points (0.15 g vs. 0.55 g at 4 hours, P < 0.001). Repeated measures analyses of the hypoxic group demonstrated a statistically significant association between potassium, lactate, and normalized peak force over the course of time. Potassium demonstrated the strongest association with a 1 mmol/L unit increase in potassium associated with a 2.9 g decrease in normalized peak force (95% confidence interval -3.3 to -2.4, P < 0.001). The pH of all muscle baths increased over the course of time at similar rates between the study groups.

CONCLUSIONS

This study used an ex vivo ischemic skeletal muscle model as a representation for pathophysiologic pathways associated with compartment syndrome. In this experimental approach we were unable to evaluate the pH of the muscle bundles due to continuous applied gassing. Our findings support further evaluations of potassium and lactate levels as potential diagnostic markers.

Well Leg Compartment Syndrome after Contralateral Femoral Neck ORIF

The authors present a case of WLCS after femoral neck fracture fixation. While this is a rare complication, a high index of suspicion should exist. Surgeons should use well leg holders with caution and limit utilization time. Alternative methods of positioning to allow for fluoroscopic imaging exist. WLCS remains a clinical diagnosis; intracompartmental measurements can be used but should be cautiously interpreted. When the diagnosis of WLCS is made, emergent fasciotomies of the affected compartments should be performed. Surgeons should be aware of this complication when using a well leg holder and the potential catastrophic consequences if left ignored.

Perfusion Pressure Lacks Diagnostic Specificity for the Diagnosis of Acute Compartment Syndrome

OBJECTIVE

To evaluate the diagnostic performance of perfusion pressure (PP) thresholds for fasciotomy.

DESIGN

Prospective observational study.

SETTING

Seven Level-1 trauma centers.

PATIENTS/PARTICIPANTS

One hundred fifty adults with severe leg injuries and ≥2 hours of continuous PP data who had been enrolled in a multicenter observational trial designed to develop a clinical prediction rule for acute compartment syndrome (ACS).

MAIN OUTCOME MEASUREMENTS

For each patient, a given PP criterion was positive if it was below the specified threshold for at least 2 consecutive hours. The diagnostic performance of PP thresholds between 10 and 30 mm Hg was determined using 2 reference standards for comparison: (1) the likelihood of ACS as determined by an expert panel who reviewed each patient's data portfolio or (2) whether the patient underwent fasciotomy.

RESULTS

Using the likelihood of ACS as the diagnostic standard (ACS considered present if median likelihood ≥70%, absent if <30%), a PP threshold of 30 mm Hg had diagnostic sensitivity 0.83, specificity 0.53, positive predictive value 0.07, and negative predictive value 0.99. Results were insensitive to more strict likelihood categorizations and were similar for other PP thresholds between 10- and 25-mm Hg. Using fasciotomy as the reference standard, the same PP threshold had diagnostic sensitivity 0.50, specificity 0.50, positive predictive value 0.04, negative predictive value 0.96.

CONCLUSION

No value of PP from 10 to 30 mm Hg had acceptable diagnostic performance, regardless of which reference diagnostic standard was used. These data question current practice of diagnosing ACS based on PP and suggest the need for further research.

LEVEL OF EVIDENCE

Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Malpractice Litigation for Compartment Syndrome

BACKGROUND

The aim of this study was to analyze litigation involving compartment syndrome to identify the causes and outcomes of such malpractice suits. A better understanding of such litigation may provide insight into areas where clinicians may make improvements in the delivery of care.

METHODS

Jury verdict reviews from the Westlaw database from January 1, 2010 to January 1, 2018 were reviewed. The search term "compartment syndrome" was used to identify cases and extract data on the specialty of the physician defendant, the demographics of the plaintiff, the allegation, and the verdict.

RESULTS

A total of 124 individual cases involving the diagnosis of compartment syndrome were identified. Medical centers or the hospital was included as a defendant in 51.6% of cases. The most frequent physician defendants were orthopedic surgeons (45.96%) and emergency medicine physicians (20.16%), followed by cardiothoracic/vascular surgeons (16.93%). Failure to diagnose was the most frequently cited claim (71.8% of cases). Most plaintiffs were men, with a mean age of 36.7 years, suffering injuries for an average of 5 years before their verdict. Traumatic compartment syndrome of the lower extremity causing nerve damage was the most common complication attributed to failure to diagnose, leading to litigation. Forty cases (32.25%) were found for the plaintiff or settled, with an average award of $1,553,993.66.

CONCLUSIONS

Our study offers a brief overview of the most common defendants, plaintiffs, and injuries involved in legal disputes involving compartment syndrome. Orthopedic surgeons were most commonly named; however, vascular surgeons may also be involved in these cases because of the large number of cases with associated arterial involvement. A significant percentage of cases were plaintiff verdicts or settled cases. Failure to diagnosis or delay in treatment was the most common causes of malpractice litigation. Compartment syndrome is a clinical diagnosis and requires a high level of suspicion for a timely diagnosis. Lack of objective criteria for diagnosis increases the chances of medical errors and makes it an area vulnerable to litigation.

Diagnostic Modalities for Acute Compartment Syndrome of the Extremities: A Systematic Review

Importance

Acute compartment syndrome (ACS) can cause catastrophic tissue damage leading to permanent muscle and nerve loss. Acute compartment syndrome is a clinical diagnosis, with intracompartmental pressure (ICP) used in equivocal cases. There are no reliable diagnostic methods. The clinical evaluation is impossible to standardize, and the threshold for ICP has been known to be unreliable; thus, guidelines for diagnosis can result in overtreatment or delayed diagnosis.

Objective

To present and review the advantages and disadvantages of each diagnostic modality and identify gaps that need to be addressed in the future and to review the most used and appropriate animal and human ACS models.

Evidence Review

We included clinical studies and animal models investigating diagnostic modalities for ACS of the extremities. A MEDLINE and Web of Science search was performed. The protocol for the study was registered on PROSPERO (CRD42017079266). We assessed the quality of the clinical studies with Newcastle-Ottawa scale and reported level of evidence for each article.

Findings

Fifty-one articles were included in this study, reporting on 38 noninvasive and 35 invasive modalities. Near-infrared spectroscopy and direct ICP measurement using a Stryker device were the most common, respectively. Cadaveric studies used saline infusions to create an ACS model. Most studies with human participants included injured patients with acquired ACS or at risk of developing ACS. In healthy human participants, tourniquets formed the most commonly used ACS model. Application of tourniquets and infusion of saline or albumin were the most used ACS models among animal studies.

Conclusions and Relevance

This article reports on the most common as well as many new and modified diagnostic modalities, which can serve as inspiration for future investigations to develop more effective and efficient diagnostic techniques for ACS. Future studies on diagnostic modalities should include the development of tools for continuous assessment of ICP to better identify the earliest alterations suggestive of impending ACS. With the advent of such technologies, it may be possible to develop far less aggressive and more effective approaches for early detection of ACS.

Risk Management and Avoiding Legal Pitfalls in the Emergency Treatment of High-Risk Orthopedic Injuries

Many orthopedic injuries can have hidden risks that result in increased liability for the emergency medicine practitioner. It is imperative that emergency medicine practitioners consider the diagnoses of compartment syndrome, high-pressure injury, spinal epidural abscess, and tendon lacerations in the right patient. Consideration of the diagnosis and prompt referrals can help to minimize the complications these patients often develop.

Diagnosing acute compartment syndrome-where have we got to?

Purpose

Acute compartment syndrome is a condition whereby tissue ischaemia occurs due to increased pressure in a closed myofascial compartment. It is a surgical emergency, with rapid recognition and treatment—the keys to good outcomes.

Methods

The available literature on diagnostic aids was reviewed by one of the senior authors 15 years ago. Now, we have further reviewed the literature, to aim to ascertain what progress has been made.

Results

In this review, we present the evidence around a variety of available diagnostic options when investigating a potential case of acute compartment syndrome, including those looking at pressure changes, localised oxygenation, perfusion, metabolic changes and available blood serum biomarkers.

Conclusions

A significant amount of work has been put into developing modalities of diagnosis for acute compartment syndrome in the last 15 years. There is a lot of promising outcomes being reported; however, there is yet to be any conclusive evidence to suggest that they should be used over intracompartmental pressure measurement, which remains the gold standard. However, clinicians should be cognizant that compartment pressure monitoring lacks diagnostic specificity, and could lead to unnecessary fasciotomy when used as the sole criterion for diagnosis. Therefore, pressure monitoring is ideally used in situations where clinical suspicion is raised.

Use of standard musculoskeletal ultrasound to determine the need for fasciotomy in an elevated muscle compartment pressure cadaver leg model

INTRODUCTION

Acute compartment syndrome (ACS) is a limb-threatening condition often associated with leg injury. The only treatment of ACS is fasciotomy with the purpose of reducing muscle compartment pressures (MCP). Patient discomfort and low reliability of invasive MCP measurements, has led to the search for alternative methods. Our goal was to test the feasibility of using ultrasound to diagnose elevated MCP.

METHODS

A cadaver model of elevated MCPs was used in 6 cadaver legs. An ultrasound transducer was combined with a pressure sensing transducer to obtain a B-mode image of the anterior compartment, while controlling the amount of pressure applied to the skin. MCP was increased from 0 to 75 mmHg. The width of the anterior compartment (CW) and the pressure needed to flatten the bulging superficial compartment fascia (CFFP) were measured.

RESULTS

Both the CW and CFFP showed high correlations to MCP in the individual cadavers. Average CW and CFFP significantly increased between baseline and the first elevated MCP states. Both Inter-observer and intra-observer agreements for the ultrasound measurements were good to excellent.

DISCUSSION

Ultrasound indexes showed excellent correlations in compartment pressures, suggesting that there is a potential for the clinical use of this modality in the future.

Bilateral Well Leg Compartment Syndrome Localized in the Anterior and Lateral Compartments following Urologic Surgery in Lithotomy Position

Well leg compartment syndrome (WLCS) is a rare but severe complication after the surgery in lithotomy position. We present a case of bilateral WLCS that occurred after the prolonged urologic surgery in lithotomy position. A 50-year-old man complained of severe bilateral lower leg pain and swelling sixteen hours after the surgery. Physical examination, elevated serum creatine kinase value, contrasting computed tomography, and elevated compartment pressure strongly suggested the development of bilateral WLCS localized in the anterior and lateral compartments. Emergent single-incision fasciotomy was performed four hours after diagnosis. The patient was treated successfully without any neuromuscular dysfunction. An early and accurate diagnosis is important to avoid the delay of treatment and development of neuromuscular dysfunction.

Continuous Near-Infrared Spectroscopy Demonstrates Limitations in Monitoring the Development of Acute Compartment Syndrome in Patients with Leg Injuries

BACKGROUND

We recorded measurements of muscle perfusion using near-infrared spectroscopy (NIRS) and intramuscular pressure (IMP) in a study designed to develop a decision rule for predicting acute compartment syndrome (ACS). The purpose of this study was to report our experience measuring NIRS data in the context of this broader investigation and to explore factors related to variations in data capture.

METHODS

One hundred and eighty-five patients with lower-leg injuries had data consisting of continuous NIRS measurement of the O2 saturation in the anterior compartment of the injured limb and the contralateral (control) limb, and continuous IMP recording in the anterior and deep posterior compartments of the injured leg as part of their participation in an institutional review board-approved multicenter trial. All monitoring was done for a prescribed period of time. For both types of data, the percentage of valid data capture was defined as the ratio of the minutes of observed data points within a physiological range to the total minutes of expected data points. Clinically useful NIRS data required simultaneous data from the injured and control limbs to calculate the ratio. Statistical tests were used to compare the 2 methods as well as factors associated with the percent of valid NIRS data capture.

RESULTS

For the original cohort, clinically useful NIRS data were available a median of 9.1% of the expected time, while IMP data were captured a median of 87.6% of the expected time (p < 0.001). Excluding 46 patients who had erroneous NIRS data recorded, the median percentage was 31.6% for NIRS compared with 87.4% for IMP data (p < 0.00001). Fractures with an associated hematoma were less likely to have valid data points (odds ratio [OR], 0.53; p = 0.04). Gustilo types-I and II open fractures were more likely than Tscherne grades C0 and C1 closed fractures to have valid data points (OR, 1.97; p = 0.03).

CONCLUSIONS

In this study, NIRS data were not collected reliably. In contrast, IMP measurements were collected during >85% of the expected monitoring period. These data raise questions about the utility of current NIRS data capture technology for monitoring oxygenation in patients at risk of ACS.

Care of Traumatic Conditions in an Observation Unit

Patients presenting to the emergency department with certain traumatic conditions can be managed in observation units. The evidence base supporting the use of observation units to manage injured patients is smaller than the evidence base supporting the management of medical conditions in observation units. The conditions that are eligible for management in an observation unit are not limited to those described in this article, and investigators should continue to identify types of conditions that may benefit from this type of health care delivery.

Predicting Acute Compartment Syndrome (PACS): The Role of Continuous Monitoring

The diagnosis of acute compartment syndrome (ACS) is a common clinical challenge among patients who sustain high-energy orthopaedic trauma, largely because no validated criteria exist to reliably define the presence of the condition. In the absence of validated diagnostic standards, concern for the potential clinical and medicolegal impact of a missed compartment syndrome may result in the potential overuse of fasciotomy in "at-risk" patients. The goal of the Predicting Acute Compartment Syndrome Study was to develop a decision rule for predicting the likelihood of ACS that would reduce unnecessary fasciotomies while guarding against potentially missed ACS. Of particular interest was the utility of early and continuous monitoring of intramuscular pressure and muscle oxygenation using near-infrared spectroscopy in the timely diagnosis of ACS. In this observational study, 191 participants aged 18-60 with high-energy tibia fractures were prospectively enrolled and monitored for up to 72 hours after admission, then followed for 6 months. Treating physicians were blinded to continuous pressure and oxygenation data. An expert panel of 9 orthopaedic surgeons retrospectively assessed the likelihood that each patient developed ACS based on data collected on initial presentation, clinical course, and known functional outcome at 6 months. This retrospectively assigned likelihood is modeled as a function of clinical data typically available within 72 hours of admission together with continuous pressure and oxygenation data. This study will improve our understanding of the natural history of compartment syndrome and examine the utility of early and continuous monitoring of the physiologic status of the injured extremity in the timely diagnosis of ACS.

Delayed Presentation of Acute Gluteal Compartment Syndrome

Patient: Male, 23

Final Diagnosis: Acute gluteal compartment syndrome

Symptoms: —

Medication: —

Clinical Procedure: Gluteal fasciotomy

Specialty: Critical Care Medicine

An early surgical training module for compartment pressure measurement

BACKGROUND

We test a novel simulated teaching module's ability to educate junior residents in the assessment of compartment syndrome (CS) and compartment pressure measurement (CPM).

METHODS

Twenty-two postgraduate year 1 and postgraduate year 2 surgical residents received a 2-hour didactic and practical teaching module on CS assessment and CPM using a simulated model. A structured teaching session by a postgraduate year 5 surgical resident was assessed by carefully constructed pretest, post-test, and delayed retention tests and a practical testing session by 2 board-certified general surgeons.

RESULTS

Analysis of variance demonstrated significant difference between pretest (6.1/10), post-test (7.9/10), and retention test (8.2/10) scores [F (2,49) = 9.24, P < .01], with no difference in post-test to retention test comparison (P = .90). Mean CPM scores were 8.5/10 for preparation, 9.0/10 for performance, and 8.5/10 for management components, which did not differ [F (2,57) = .46, P = .63].

CONCLUSIONS

We demonstrate an efficient simulated CS and CPM teaching module for the education of junior surgical residents using a synthetic model.

Evaluation of a fiber-optic technique for recording intramuscular pressure in the human leg

To evaluate a forward-sensing fiber-optic pressure technique for recording of intramuscular pressure (IMP) in the human leg and investigate factors that may influence IMP measurements used in diagnosing compartment syndromes. IMP in the tibialis anterior muscle was recorded simultaneously by a fiber-optic technique and needle-injection technique in 12 legs of 7 healthy subjects. Both measurement catheters were placed in parallel with the muscle fibers to the same depth, as verified by sonography. IMP recordings were performed at rest before, during and after applying a model of abnormally elevated IMP (simulated compartment syndrome). IMP was elevated by venous obstruction induced by a thigh tourniquet of a casted leg. IMP was also measured during injections of 0.1 ml of saline into the muscle through the catheters. IMP at baseline was 5.1 (SD = 2.6) mmHg measured with the fiber-optic technique and 7.1 (SD = 2.5) mmHg with the needle-injection technique (p < 0.001). It increased to 48.5 (SD = 6.9) mmHg and 47.6 (SD = 6.6) mmHg respectively, during simulated compartment syndrome. IMP increased significantly following injection of 0.1 ml of saline, measured by both techniques. It remained increased 1 min after injection. The fiber-optic technique was able to record pulse-synchronous IMP oscillations. The fiber-optic technique may be used for IMP measurements in a muscle with both normal and abnormally elevated IMP. It has good dynamic properties allowing for measurement of IMP oscillations. Saline injection used with needle-injection systems to ensure catheter patency compromises IMP readings at least one minute after injection.

Acute compartment syndrome in orthopedics: causes, diagnosis, and management

Almost all orthopaedic surgeons come across acute compartment syndrome (ACS) in their clinical practice. Diagnosis of ACS mostly relies on clinical findings. If the diagnosis is missed and left untreated, it can lead to serious consequences which can endanger limb and life of the patient and also risk the clinician to face lawsuits. This review article highlights the characteristic features of ACS which will help an orthopaedic surgeon to understand the pathophysiology, natural history, high risk patients, diagnosis, and surgical management of the condition.