Lower Leg Lateral Chronic Exertional Compartment Syndrome: Prospective Surgical Treatment Outcomes for Isolated or Combined Lateral Fasciotomy.

BACKGROUND: Chronic exertional compartment syndrome involving the lower leg lateral compartment (lat-CECS) seldom occurs isolated but is usually combined with CECS of the anterior (ant-CECS) or deep posterior compartment (dp-CECS). Patient characteristics in lat-CECS and outcome after surgery are largely unknown. The aim of this prospective case series was to describe patient characteristics and symptoms and to report on outcome following a fasciotomy. METHODS: All patients diagnosed with lat-CECS based on exertional lateral lower leg symptoms and elevated intracompartmental pressure (ICP) measurements according to the Pedowitz criteria (ICP ≥ 15 mm Hg at rest, and/or ≥30 mm Hg after 1 minute, and/or ≥20 mm Hg 5 minutes after exercise) were eligible for this study. A standard intake questionnaire scoring symptom patterns was completed by all patients. Patients who were operated for lat-CECS were asked to complete a 3-month and 12-month postoperative questionnaire scoring symptoms and surgical outcome. Patients with a history of CECS surgery, recent lower leg trauma, or peripheral neurovascular disease were excluded. RESULTS: A total of 881 patients with possible lower leg CECS completed an intake questionnaire and 88 (10%) were diagnosed with lat-CECS according to the Pedowitz criteria (isolated lat-CECS n = 10; lat/ant CECS n = 54, lat/ant/dp CECS n = 19, lat/dp CECS n = 5). Severe pain during exercise and moderate tightness during rest were frequently reported. A group of 28 patients (49 legs; isolated lat-CECS n = 2; lat/ant CECS n = 22, lat/ant/dp CECS n = 3, lat/dp CECS n = 1) was analyzed after fasciotomy. Complications were minor (wound infection requiring antibiotics, n = 3; temporary complex regional pain syndrome with spontaneous recovery, n = 1). Superficial peroneal nerve damage was not observed. One year after surgery, 64% rated outcome as excellent or good, whereas 71% had resumed sports activities. CONCLUSION: One in 10 patients with anterolateral exertional lower leg pain evaluated in a tertiary referral center met diagnostic criteria for lat-CECS. Pain and tightness were present during exertion and were often reported occurring during rest and at night. In this series, we found fasciotomy-either an isolated (lateral) or a multiple (combined with anterior and/or deep posterior) compartment fasciotomy-is safe and beneficial in most patients. LEVEL OF EVIDENCE: Level IV, case series.

Comparison of 2 Fasciotomes for Treatment of Patients With Chronic Exertional Compartment Syndrome of the Anterior Leg.

BACKGROUND: Chronic exertional compartment syndrome (CECS) of the anterior leg compartment (ant-CECS) is frequently treated with a minimally invasive fasciotomy. Several operative techniques and operative devices exist, but none have been compared in a systematic and randomized manner. PURPOSE: To compare efficacy, safety, and postoperative pain of a novel operative device (FascioMax fasciotome) with a widely accepted device created by Due and Nordstrand (Due fasciotome) during a minimally invasive fasciotomy for ant-CECS. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: Patients with bilateral isolated ant-CECS between October 2013 and April 2018 underwent a minimally invasive fasciotomy using the FascioMax fasciotome in 1 leg and the Due fasciotome in the contralateral leg in a single operative session. Symptom reduction at 3 to 6 months and >1 year, postoperative pain within the first 2 weeks, peri- and postoperative complications, and ability to regain sports were assessed using diaries, physical examination, and timed questionnaires. RESULTS: Included in the study were 50 patients (66% female; median age, 22 years [range, 18-65 years]). No differences between the devices were found in terms of perioperative complications (both had none), minor postoperative complications including hematoma and superficial wound infection (overall complication rate: FascioMax, 8% vs Due, 6%), or reduction of CECS-associated symptoms at rest and during exercise. At long-term follow-up (>1 year), 82% of the patients were able to regain their desired type of sport, and 67% (33/49) were able to exercise at a level that was comparable with or higher than before their CECS-associated symptoms started. CONCLUSION: Both the FascioMax and the Due performed similarly in terms of efficacy, safety, and levels of pain within the first 2 weeks postoperatively. REGISTRATION: NL4274; Netherlands Trial Register.

Chronic exertional compartment syndrome in the differential diagnosis of peripheral artery disease in older patients with exercise-induced lower limb pain.

OBJECTIVE: Peripheral artery disease (PAD) and chronic exertional compartment syndrome (CECS) both cause exercise-induced lower limb pain. CECS is mostly described in young individuals and may therefore not be considered in older patients with intermittent claudication. The aim of our study was to identify differences in characteristics and symptomatology between patients with CECS and PAD that may help in recognizing CECS in patients ≥50 years with exercise-induced lower limb pain. METHODS: In this case-control study, patients with CECS ≥50 years were selected from a prospectively followed cohort and compared with a sample of newly diagnosed patients with PAD ≥50 years. A questionnaire assessed frequency and severity of lower limb pain, tightness, cramps, muscle weakness, and altered skin sensation at rest and during exercise. RESULTS: At rest, patients with CECS (n = 43, 42% female, 57 years; range, 50-76 years) reported significantly more pain, tightness, muscle weakness and altered skin sensation (all P < .01) than patients with PAD (n = 41, 39% female, 72 years; range, 51-93 years). Having CECS was associated with a significantly higher combined symptom score at rest (P = .02). During exercise, patients with CECS experienced more tightness, muscle weakness and altered sensation (P < .01), but not pain and cramps (P = .36; P = .70). Exercise-induced complaints occurred much later in patients with CECS than in patients with PAD (15 minutes vs 4 minutes; P < .01). Persistence of pain over 4.5 minutes proved most discriminative for the presence of CECS (sensitivity, 95%; specificity, 54%; positive predictive value, 65%). Exercise cessation completely alleviated complaints in all patients with PAD (n = 41) but not in 73% (n = 29) of the patients with CECS. Ongoing discomfort strongly predicted the presence of CECS (sensitivity, 73%; specificity, 100%; positive predictive value, 100%). CONCLUSIONS: Patients with CECS ≥50 years report a symptom pattern that is different from patients with PAD. These differences may aid vascular surgeons in identifying older patients with CECS.

Superficial Peroneal Nerve Injury Risk During a Semiblind Fasciotomy for Anterior Chronic Exertional Compartment Syndrome of the Leg: An Anatomical and Clinical Study.

BACKGROUND:: Up to 8% of patients who underwent a fasciotomy for leg anterior chronic exertional compartment syndrome (ant-CECS) report sensory deficits suggestive of iatrogenic superficial peroneal nerve (SPN) injury. In the current study we aimed to thoroughly assess the risk of SPN injury during a semiblind fasciotomy of the anterior compartment using 2 separate approaches. METHODS:: A modified semiblind fasciotomy of the anterior compartment was performed via a longitudinal 2-cm skin incision 2 cm lateral of the anterior tibial crest halfway along the line fibular head-lateral malleolus both in cadaver legs and in patients with ant-CECS. In the cadaver legs, the skin was removed after the procedure and possible SPN injuries and spatial relationships between the SPN and the opened fascia were studied. Between January 2013 and December 2016, 64 ant-CECS patients who underwent a fasciotomy of the anterior compartment were prospectively followed. Iatrogenic SPN injuries were assessed using questionnaires and physical examinations. RESULTS:: Macroscopic SPN nerve injury was not observed in any of the 9 cadaver legs. In 8 specimens, the SPN was located at least 5 mm posterolateral to the opened fascia. In 1 specimen, an undamaged SPN branch crossed the operative field in a ventral plane. De novo sensory deficits suggestive for iatrogenic SPN injury were not observed in any of the 64 patients (120 legs; 36 females; median age, 22 years) who underwent a fasciotomy of the anterior compartment. CONCLUSION:: The proposed semiblind fasciotomy for treatment of ant-CECS was not associated with SPN injury in either the cadaveric study or our clinical series. LEVEL OF EVIDENCE:: Level IV, case series.

Isolated Lateral Chronic Exertional Compartment Syndrome of the Leg: A New Entity?

BACKGROUND: Chronic exertional compartment syndrome (CECS) mostly occurs in the anterior or deep posterior compartments (ant-CECS and dp-CECS, respectively) of the leg. It is generally accepted that CECS of the third or lateral compartment (lat-CECS) always occurs together with ant-CECS. However, whether exertional leg pain (ELP) can be caused by an isolated form of lat-CECS is unknown. PURPOSE: To determine the existence of isolated lat-CECS and study whether history taking and a physical examination aid in discriminating between different subtypes of CECS. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients were eligible for this single-center study, conducted between January 2013 and February 2018, if they reported anterolateral ELP and completed a questionnaire scoring the frequency and intensity of pain, tightness, cramps, muscle weakness, and paresthesia during rest and exercise. They were asked to mark areas of altered foot skin sensation, if present, on a drawing. All patients underwent a dynamic intracompartmental pressure (ICP) measurement of the anterior and lateral compartments simultaneously. The diagnosis of CECS was confirmed by elevated ICP (Pedowitz criteria). There were 3 patient groups: (1) isolated ant-CECS with elevated ICP in the anterior compartment and normal ICP in the lateral compartment, (2) isolated lat-CECS with elevated ICP in the lateral compartment but normal ICP in the anterior compartment, and (3) ant-/lat-CECS with elevated ICP in both the anterior and lateral compartments. RESULTS: A total of 73 patients with anterolateral ELP fulfilled study criteria (isolated ant-CECS: n = 26; isolated lat-CECS: n = 5; ant-/lat-CECS: n = 42). Group differences were not observed regarding age (isolated ant-CECS: median, 26 years [range, 13-68 years]; isolated lat-CECS: median, 20 years [range, 17-63 years]; ant-/lat-CECS: median, 28 years [range, 17-57 years]; χ2 (2) = 0.466; P = .79), sex (isolated ant-CECS: 50% male; isolated lat-CECS: 40% male; ant-/lat-CECS: 62% male; P = .49), or bilateral symptoms (isolated ant-CECS: 54%; isolated lat-CECS: 80%; ant-/lat-CECS: 69%; P = .40). However, cramps at rest were present in a portion of the patients with isolated ant-CECS (38%) and ant-/lat-CECS (57%) but not in those with isolated lat-CECS (P = .032). Patient drawings of altered foot skin sensation did not contribute to the diagnosis (P = .92). ICP values after provocation were all lower in patients with isolated ant-CECS and isolated lat-CECS compared with those with ant-/lat-CECS (P < .05). CONCLUSION: Seven percent of patients with CECS and anterolateral ELP who had symptoms due to isolated lat-CECS in the presence of normal muscle pressure in the anterior compartment.

Lower Leg Chronic Exertional Compartment Syndrome in Patients 50 Years of Age and Older.

BACKGROUND: Lower leg chronic exertional compartment syndrome (CECS) is usually diagnosed in young and athletic individuals. The presence of CECS in older patients has received little attention in the literature, and patient characteristics are unknown. PURPOSE: To determine the prevalence of CECS in older patients (≥50 years) and to assess whether older patients with CECS differ clinically from younger patients with CECS. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: All individuals with exercise-induced lower leg pain who visited a referral center for CECS between January 2001 and December 2013 were eligible for analysis. Patients were included if history, physical examination, and dynamic intracompartmental pressure measurement indicated CECS. Characteristics of patients 50 years of age or older were compared with characteristics of patients younger than 50. RESULTS: A total of 698 patients with CECS were included: 98 patients were aged 50 years or older and 600 patients were younger than 50 years. Older individuals more often reported a history of lower leg events or comorbidities (≥50 years, 45% vs <50 years, 25%; P < .01) and unilateral symptoms (≥50 years, 45% vs <50 years, 22%; P < .01). Most older patients (62%) did not participate in sport or only walked or hiked, whereas the same was true of only 7% of the younger population. Pain (≥50 years, 94%; <50 years, 96%) and tightness (≥50 years, 57%; <50 years, 62%) were the predominant symptoms of CECS in both groups. Type of CECS differed significantly (P < .01); the anterior muscle compartment was involved more frequently in older patients (≥50 years, 82% vs <50 years, 59%) and deep flexor muscle CECS was more often diagnosed in younger patients (≥50 years, 26% vs <50 years, 53%). CONCLUSION: In the present population, 1 in 7 patients diagnosed with lower leg CECS was 50 years of age or older. These individuals were less active and had more comorbidities than patients younger than 50 years. Older individuals predominantly have anterior CECS. Clinicians should consider CECS in older individuals with exercise-induced lower leg pain, particularly if it is unilateral.

Factors Predicting Lower Leg Chronic Exertional Compartment Syndrome in a Large Population.

Knowledge about lower leg chronic exertional compartment syndrome (CECS) is largely obtained from highly selected populations. Patient characteristics may therefore not be appropriate for the general population. Our purpose was to describe a heterogeneous population of individuals suspected of lower leg CECS and to identify predictors of CECS. Charts of individuals who were analyzed for exercise-induced lower leg pain in a referral center between 2001 and 2013 were retrospectively studied. Patients were included if history and physical examination were suggestive of CECS and if they had undergone a dynamic intracompartmental pressure measurement. Six hundred ninety-eight of 1411 individuals were diagnosed with CECS in one or more of three lower leg muscle compartments (anterior tibial, deep flexor, lateral). Prevalence of CECS peaked around the age of 20-25 years and decreased thereafter, although a plateau around 50 years was found. Age, gender, bilateral symptoms, previous lower leg pathology, sports (running and skating) and tender muscle compartments were identified as independent predictors of lower leg CECS. The proposed predictive model has moderate discriminative ability (AUC 0.66) and good calibration over the complete range of predicted probabilities. The predictive model, displayed as a nomogram, may aid in selecting individuals requiring an invasive dynamic intracompartmental muscle pressure measurement.

Role of Repeat Muscle Compartment Pressure Measurements in Chronic Exertional Compartment Syndrome of the Lower Leg.

BACKGROUND: The diagnostic gold standard for diagnosing chronic exertional compartment syndrome (CECS) is a dynamic intracompartmental pressure (ICP) measurement of the muscle. The potential role of a repeat ICP (re-ICP) measurement in patients with persistent lower leg symptoms after surgical decompression or with ongoing symptoms after an earlier normal ICP is unknown. PURPOSE: To study whether re-ICP measurements in patients with persistent CECS-like symptoms of the lower leg may contribute to the diagnosis of CECS after both surgical decompression and a previously normal ICP measurement. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Charts of patients who underwent re-ICP measurement of lower leg compartments (anterior [ant], deep posterior [dp], and/or lateral [lat] compartments) between 2001 and 2013 were retrospectively studied. CECS was diagnosed on the basis of generally accepted cutoff pressures for newly onset CECS (Pedowitz criteria: ICP at rest ≥15 mmHg, ≥30 mmHg after 1 minute, or ≥20 mmHg 5 minutes after a provocative test). Factors predicting recurrent CECS after surgery or after a previously normal ICP measurement were analyzed. RESULTS: A total of 1714 ICP measurements were taken in 1513 patients with suspected CECS over a 13-year observation period. In all, 201 (12%) tests were re-ICP measurements for persistent lower leg symptoms. Based on the proposed ICP cutoff values, CECS recurrence was diagnosed in 16 of 62 previously operated compartments (recurrence rate, 26%; 53 patients [64% female]; median age, 24 years; age range, 15-78 years). Recurrence rates were not different among the 3 lower leg CECS compartments (ant-CECS, 17%; dp-CECS, 33%; lat-CECS, 30%; χ2 = 1.928, P = .381). Sex (χ2 = 0.058, P = .810), age (U = 378, z = 1.840, P = .066), bilaterality (χ2 = 0.019, P = .889), and prefasciotomy ICP did not predict recurrence. Re-ICP measurements evaluating 20 compartments with previously normal ICP measurements (15 patients [53% female]; mean age, 31 ± 10 years) detected CECS in 3 compartments (15%, all ant-CECS). CONCLUSION: Previous fasciotomy for lower leg CECS or previously normal muscle pressure (ICP) do not rule out CECS as a cause of persisting lower leg symptoms. Repeat ICP measurement may have a potential role in the evaluation of patients with persistent lower leg complaints. However, other reasons for lower leg exertional pain must always be considered prior to secondary surgery.

Fasciotomy for Deep Posterior Compartment Syndrome in the Lower Leg: A Prospective Study.

BACKGROUND: Patients with exercise-induced lower leg pain may suffer from deep posterior chronic exertional compartment syndrome (dp-CECS). Current evidence for the efficacy of surgery is based on retrospective studies. Effects of fasciotomy on symptoms associated with dp-CECS have not been systematically studied, and reasons for unsuccessful surgery are unknown. PURPOSE: To report the short- and long-term effects of fasciotomy on pain, tightness, and cramps in a prospective cohort of patients with isolated dp-CECS. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between September 2011 and January 2015, pain, tightness, cramps, muscle weakness, and diminished sensation were scored (5-item verbal rating scale ranging from very severe [5 points] to absent [1 point]) in patients with dp-CECS before and after fasciotomy. Outcomes were graded as excellent, good, moderate, fair, or poor. Fair and poor cases were again analyzed during a follow-up visit in the outpatient department. RESULTS: Forty-four patients underwent surgery for isolated dp-CECS. Short-term follow-up (median, 4 months; range, 3-7 months) was complete in 42 of the 44 patients (95%; median patient age, 23 years; 23 male; 64 operated legs). Long-term follow-up (median, 27 months; range, 12-42 months) was complete in 34 of 37 eligible patients (92%). Before surgery, exertional pain was very severe (27%) or severe (61%). Fasciotomy improved all symptoms, both in the short term (preoperative vs postoperative pain, 4.1 ± 0.6 vs 2.3 ± 1.1; P < .001) and the long term (pain, 4.2 ± 0.6 vs 2.7 ± 1.3; P < .001). Levels of tightness, cramps, muscle weakness, and diminished sensation demonstrated similar significant improvements. Short- and long-term symptom scores did not differ. The short-term outcome was excellent in 29%, good in 29%, moderate in 21%, fair in 12%, and poor in 10% of patients. In the long term, outcomes were similar (excellent, 12%; good, 35%; moderate, 24%; fair, 18%; and poor, 12%). An unsatisfactory outcome (fair or poor) was often caused by alternative types of CECS (eg, anterior or lateral CECS) or to medial tibial stress syndrome. Based on their outcome, 76% of patients would opt for surgery again. CONCLUSION: Fasciotomy was beneficial in 71% of patients with dp-CECS in the lower leg; 47% of study patients experienced a good to excellent outcome. Outcomes were stable in the long term. Persistent complaints were often caused by other untreated conditions.

Feasibility and Safety of an Operative Tool for Anterior Chronic Exertional Compartment Syndrome Treatment.

BACKGROUND: Operative management of chronic exertional compartment syndrome of the tibialis anterior muscle compartment (ant-CECS) usually involves the use of a fasciotome. Collateral tissue damage such as hematoma and nerve damage may occur during the procedure. The current report assessed the feasibility and safety of an alternative tool for the operative management of ant-CECS. METHODS: The system had a speculum-like hollow tube that was inserted via a 2-cm skin incision and allowed for the protected advancement of a fasciotome. The device was tested in patients with bilateral ant-CECS. Symptoms were prospectively scored before and after surgery using a 5-category verbal rating scale (VRS). Fourteen patients (age 26 ± 10 years) were analyzed. Complications and operative efficacy were determined using physical examination and questionnaires after 21 (range = 16-25) months. RESULTS: Technical operative success rate was 100% (28/28 legs). Operation time was 10 ± 2 minutes per leg (range = 6-14). Perioperative complications were not observed. One superficial wound infection was treated nonoperatively. Significant reductions in pain (-2.2 ± 1.1 on 5-point VRS, P < .001), tightness (-1.9 ± 1.6, P = .01), cramps (-1.4 ± 1.6, P = .009), muscle weakness (-1.6 ± 1.2, P < .001), and altered sensibility (-1.3 ± 1.4, P = .005) were registered 21 months postoperatively. CONCLUSION: This fasciotome was simple to use and allowed for a safe fasciotomy in patients with leg ant-CECS. A randomized controlled trial comparing the present device with a widely used fasciotome was under way at the time of writing of this study.

Isolated Chronic Exertional Compartment Syndrome of the Lateral Lower Leg: A Case Series.

BACKGROUND: Exercise-induced lower leg pain may be caused by chronic exertional compartment syndrome (CECS). The anterior (ant-CECS) or deep posterior compartment (dp-CECS) is usually affected. Knowledge regarding CECS of the lateral compartment (lat-CECS) is limited. PURPOSE: To describe demographic characteristics and symptoms in a consecutive series of patients with isolated CECS of the lateral compartment of the leg. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Since 2001, patients undergoing dynamic intracompartmental pressure (ICP) measurements for suspected CECS in a single institution were prospectively monitored. Individuals with a history possibly associated with lat-CECS and elevated ICP measurements (Pedowitz criteria) were identified. Exclusion criteria were concomitant ipsilateral ant-CECS/dp-CECS, acute compartment syndrome, recent significant trauma, peroneal nerve entrapment, or vascular claudication. RESULTS: During an 11-year time period, a total of 26 patients with isolated lat-CECS fulfilled study criteria (15 females; median age, 21 years; range, 14-48 years). Frequently identified provocative sports were running (n = 4), walking (n = 4), field hockey (n = 3), soccer (n = 3), and volleyball (n = 2). Exercise-induced lateral lower leg pain (92%) and tightness (42%) were often reported. The syndrome was bilateral in almost two-thirds (62%, n = 16). Delay in diagnosis averaged 24 months (range, 2 months to 10 years). CONCLUSION: Young patients with exercise-induced pain in the lateral portions of the lower leg may suffer from isolated CECS of the lateral compartment. ICP measurements in the lateral compartment in these patients are recommended.

Evolutionary pathways of transmitted drug-resistant HIV-1.

Several large studies in Europe and the USA revealed that approximately 10% of all newly diagnosed patients harbour HIV-1 variants with at least one major resistance-associated mutation. In this review we discuss the underlying mechanisms that drive the evolution of drug-resistant viruses after transmission to the new host. In a comprehensive literature search 12 papers describing the evolution of 58 cases of transmitted resistant HIV-1 variants were found. Based on observations in the literature we propose three pathways describing the evolution of resistant HIV-1 after transmission to a new host. Firstly, reversion of the resistance mutation towards wild-type may rapidly occur when drug resistance mutations severely impact replicative capacity. Alternatively, a second pathway involves replacement of transmitted drug resistance mutations by atypical amino acids that also improve viral replication capacity. In the third evolutionary pathway the resistance mutations persist either because they do not significantly affect viral replication capacity or evolution is constrained by fixation through compensatory mutations. In the near future ultra-sensitive resistance tests may provide more insight into the presence of archived and minority variants and their clinical relevance. Meanwhile, clinical guidelines advise population sequence analysis of the baseline plasma sample to identify transmission of resistance. Given the limited sensitivity of this technique for minority populations and the delay between the moment of infection and time of analysis, knowledge of the described evolutionary mechanisms of transmitted drug resistance patterns is essential for clinical management and public health strategies.