The effect of gender on intramuscular pressure in patients with chronic exertional compartment syndrome of the lower leg.

This study aimed to compare intramuscular pressure (IMP) in all four compartments of the lower leg between men and women in patients with suspected chronic exertional compartment syndrome (CECS), and to assess possible effects of gender in relation to covariation factors. A consecutive series of patients with exertional leg pain (n = 962, median age 27 years, 56.2% women) underwent IMP measurements between 2009 and 2019. The CECS diagnosis was confirmed (n = 491, 48% women) or ruled out (n = 471, 65% women) based on the patient's history, clinical examination, and IMP measurements. IMP values of the compartments were compared between genders. A multiple linear regression analysis was performed for IMP in the anterior and lateral compartments, where the number of patients was large enough to investigate the possible impact of other factors such as height, age, and duration of pain. Among those with a confirmed CECS diagnosis, one-minute post-exercise IMP was significantly lower in women than in men for all four muscle compartments: anterior (median [range] mmHg 44 [24-120] vs. 50 [24-130]), lateral (35 [20-89] vs. 40 [26-106]), deep posterior (31 [25-36] vs. 34 [24-53]), and superficial posterior (32 [27-39] vs. 37 [22-54]). In the multiple regression analysis, gender differences remained significant in the anterior compartment but not the lateral compartment, where only height remained a significant predictor of IMP. Gender should be considered when using cut-off values for IMP in diagnosing CECS, especially for the anterior compartment.

Cervical spine and muscle adaptation after spaceflight and relationship to herniation risk: protocol from 'Cervical in Space' trial.

BACKGROUND: Astronauts have a higher risk of cervical intervertebral disc herniation. Several mechanisms have been attributed as causative factors for this increased risk. However, most of the previous studies have examined potential causal factors for lumbar intervertebral disc herniation only. Hence, we aim to conduct a study to identify the various changes in the cervical spine that lead to an increased risk of cervical disc herniation after spaceflight. METHODS: A cohort study with astronauts will be conducted. The data collection will involve four main components: a) Magnetic resonance imaging (MRI); b) cervical 3D kinematics; c) an Integrated Protocol consisting of maximal and submaximal voluntary contractions of the neck muscles, endurance testing of the neck muscles, neck muscle fatigue testing and questionnaires; and d) dual energy X-ray absorptiometry (DXA) examination. Measurements will be conducted at several time points before and after astronauts visit the International Space Station. The main outcomes of interest are adaptations in the cervical discs, muscles and bones. DISCUSSION: Astronauts are at higher risk of cervical disc herniation, but contributing factors remain unclear. The results of this study will inform future preventive measures for astronauts and will also contribute to the understanding of intervertebral disc herniation risk in the cervical spine for people on Earth. In addition, we anticipate deeper insight into the aetiology of neck pain with this research project. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00026777. Registered on 08 October 2021.

Significantly lower intramuscular pressure in the posterior and lateral compartments compared with the anterior compartment suggests alterations of the diagnostic criteria for chronic exertional compartment syndrome in the lower leg.

PURPOSE: To investigate distributions and identify possible differences in intramuscular pressure (IMP) values at 1 min post-exercise between the four muscle compartments of the lower leg, in patients with exertional leg pain with or without chronic exertional compartment syndrome (CECS). METHODS: A consecutive series of patients seeking orthopaedic consultation for exertional leg pain underwent IMP measurements between 2009 and 2018. The diagnosis of CECS was confirmed (n = 442) or ruled out (n = 422), based on the patient's history, clinical examination, and IMP measurements. RESULTS: The median (range) 1 min post-exercise IMP values in affected compartments in the patients diagnosed with CECS were 33 (25-53) mmHg (deep posterior), 35 (27-54) mmHg (superficial posterior), 40 (26-106) mmHg (lateral), and 47 (24-120) mmHg (anterior). In patients with no CECS, the median (range) 1 min post-exercise IMP values in the compartments were 12 (2-28) mmHg (deep posterior), 12 (2-27) mmHg (superficial posterior), 14 (2-26) mmHg (lateral), and 18 (4-34) mmHg (anterior). The IMP was significantly lower in the lateral and both posterior compartments than in the anterior compartment in both patients diagnosed with CECS and patients without CECS. CONCLUSION: The study demonstrates significantly lower IMP values in the posterior and lateral compartments compared to the anterior compartments. These findings suggest a lowering of the IMP 1 min post-exercise cut-off value for diagnosing CECS in the lateral and both posterior compartments, which may lead to improved treatment of patients with suspected CECS in the lower leg. LEVEL OF EVIDENCE: Level II.

Detection of changes in muscle oxygen saturation in the human leg: a comparison of two near-infrared spectroscopy devices.

The purpose of this study was first to evaluate the near infrared spectroscopy (NIRS) device, INVOS 4100 as a method of measuring exercise and arterial occlusion induced muscle ischemia in human leg, by comparison with InSpectra tissue spectrometer Model 325, and secondly to determine the influence of skin and subcutaneous thickness on the NIRS measurements. Twenty healthy subjects (43 ± 8 years) volunteered for the study. Tissue oxygen saturation (StO2) in the anterior tibial muscle was measured simultaneously with InSpectra Model 325 in one leg and INVOS 4100 in the contralateral leg during an exercise test until muscle exhaustion and arterial occlusion with and without exercise. The skin and subcutaneous thickness was identified by ultrasound imaging. Baseline StO2 was 87 ± 8 % detected by InSpectra and 76 ± 6 % by INVOS. Both devices detected an immediate decrease of StO2 (p < 0.001) during exercise, arterial occlusion with and without exercise, and a significant post ischemic hyperaemia (p < 0.001) during recovery. There was a significant inverse correlation between skin and subcutaneous thickness and baseline StO2 (r = -0.78, p < 0.01) as well as change in StO2 during exercise (r = -0.65, p = 0.002) for InSpectra, which was not apparent for INVOS. The results demonstrate that the cerebral/somatic oxygenation monitor (INVOS) is able to detect experimentally induced skeletal muscle ischemia in the human leg as well as the peripheral tissue spectrometer (InSpectra). Muscle oxygen saturation measurement by INVOS is less affected by skin and subcutaneous thickness than measured by InSpectra.

Chronic exertional compartment syndrome of the forearm diagnosed in a wider spectrum of patients and not seldom with a history of the same diagnosis in the lower legs.

Purpose: To identify patient characteristics associated with forearm chronic exertional compartment syndrome (CECS) and to demonstrate the distribution of intramuscular pressure (IMP) values at 1 min postexercise in a cohort of patients with exercise-induced forearm pain. Methods: A consecutive series of 99 patients seeking orthopaedic consultation for chronic exertional forearm pain underwent IMP measurements between 2010 and 2023. The diagnosis of CECS was confirmed (n = 34) or ruled out (n = 65) based on the patient's history, clinical examination and IMP measurements. Results: There were significantly more male patients in the CECS group than in the group of patients where the diagnosis was ruled out. Furthermore, a significantly higher proportion of the CECS patients had been previously treated for CECS of the lower legs. The most common occupation was office worker (21%), followed by craftsperson (18%). The most common main physical activities were strength training (21%) and cycling (15%). The median (range) 1-min postexercise IMP values for patients with CECS were 34 (23-68) mmHg for the flexor compartment and 32 (25-67) mmHg for the extensor compartment. Conclusion: This study demonstrates a more general population of CECS patients compared to previous studies. Notably, more than a fifth of the CECS patients had previously been treated for CECS in the lower legs. Importantly, considering the 95% confidence interval for IMP values in patients without CECS, the most used IMP cutoff value for diagnosing CECS appears to be too high for the forearm compartments. Level of Evidence: Level II.

Intramuscular Pressure and Patient-Reported Outcomes in Patients Surgically Treated for Anterior Chronic Exertional Compartment Syndrome.

Background: Chronic exertional compartment syndrome (CECS) causes exercise-induced leg pain. The diagnosis is confirmed by intramuscular pressure (IMP) measurements. Fasciotomy has been demonstrated to be a successful treatment for CECS; however, few studies have examined postoperative IMP and long-term outcomes. Purpose: To evaluate long-term outcomes and postoperative IMP in patients surgically treated for anterior CECS, and to identify possible preoperative or postoperative factors associated with overall satisfaction with treatment at follow-up. Study Design: Case-control study; Level of evidence, 3. Methods: A consecutive series of 209 patients who underwent fasciotomy of the anterior compartment for CECS between 2009 and 2019 and had at least 1 year of follow-up were approached for inclusion. A total of 144 patients (69%), with a follow-up time of 1 to 11.5 years, were ultimately included. All patients underwent preoperative and postoperative 1-minute postexercise IMP measurements of the anterior compartment and completed a questionnaire covering pain and activity parameters at both time points. The follow-up questionnaire included an additional question on overall satisfaction with treatment, and surgical details were collected from the patient's medical records. Results: The median IMP was significantly lower at follow-up than at baseline (17 mm Hg [range, 5-91 mm Hg] vs 49 mm Hg [range, 25-130 mm Hg]; P < .001). The overall satisfaction rate was 77%, and 83% reported a decreased pain level. The group of patients who were satisfied with the treatment included more men and had a higher ΔIMP and a lower revision rate (P < .05). Among the 16 patients (11%) who had undergone revision fasciotomies before follow-up, the satisfaction rate was 56%, and 64% reported a decrease in pain level. Conclusion: Fasciotomy significantly reduced 1-minute postexercise IMP in patients with CECS and resulted in satisfaction and decreased pain in more than three-quarters of the patients at long-term follow-up. The male sex and a significant decrease in IMP were both positively associated with treatment satisfaction. Patients who underwent revision surgery before the follow-up had lower satisfaction rates and less pain reduction than the overall group.

Effects of Exercise Compression Stockings on Anterior Muscle Compartment Pressure and Oxygenation During Running: A Randomized Crossover Trial Conducted in Healthy Recreational Runners.

BACKGROUND: Exercise compression garments have increased in popularity among athletes at all levels during the last 10 years. However, the scientific grounds for this are unclear. The purpose of the present study was to examine the effect of wearing exercise compression stockings (CS) on the anterior compartment pressure, oxygenation of the tibialis anterior muscle, and early blood biomarkers change for muscle damage during a 10-km treadmill run in healthy subjects. METHODS: Twenty healthy subjects completed two identical treadmill runs, with or without CS. The subjects were randomized regarding the order in which the sessions were performed. Intramuscular pressure (IMP) and muscle oxygenation in the one leg were continuously measured before, during, and after running sessions. Blood samples were collected just before and directly after these sessions and analyzed for myoglobin and creatine kinase concentrations. RESULTS: The use of CS during running resulted in significantly higher IMP (by 22 ± 3.1 mmHg on average) and lower tissue oxygenation index (by 11 ± 1.8%) compared to running without CS (p < 0.001). In addition, the Δ change in median serum myoglobin concentration measured before and after running was significantly higher when CS were used: 58 (9‒210) µg/L as compared to 38 (0‒196) µg/L with no CS (p = 0.04). No difference in post-running early serum creatine kinase concentration was observed between using CS and not using CS. CONCLUSION: Wearing exercise CS during and following a 10-km treadmill run elevated IMP and reduced muscle tissue oxygenation in the anterior compartment of healthy runners. Furthermore, the use of exercise CS did not prevent early exercise-induced muscle damage, as measured by serum biomarkers.

Patient pain drawing is a valuable instrument in assessing the causes of exercise-induced leg pain.

AIM: We validated patientpain drawing (PPD) in establishing the diagnosis of chronic anterior compartment syndrome (CACS) in patients with exercise-induced leg pain. METHODS: The study comprised 477 consecutive patients, all suspected of having CACS. The diagnosis was based on the patient's history, a thorough clinical examination and measurements of intramuscular pressure (IMP) following an exercise test. Patients completed a PPD before their hospital visit. Two independent orthopaedic surgeons diagnosed the causes of leg pain based only on the PPD at least 1 year after admission. Based on the results of diagnostic tests, the patients were divided into three groups: CACS (n=79), CACS with comorbidity (n=89) and non-CACS (n=306). RESULTS: The sensitivity of the PPD to identify CACS correctly was 67% (observer 1) and 75% (observer 2). The specificity was 65% and 54%, respectively. The interobserver agreement (n=477) was 80%, and the kappa value was 0.55. The interobserver agreement was 77%, and the kappa value was 0.48 among 168 CACS patients with or without comorbidity. The interobserver agreement was 85%, and the kappa value was 0.56 in 79 CACS, and CACS was correctly diagnosed in 79% (observer 1) and 82% (observer 2). The test-retest showed the same results for the two observers, with an intraobserver agreement of 84%, while the test-retest reliability coefficient was 0.7. Comorbidity was found in 53% of CACS patients. CONCLUSION: PPD might be a valuable instrument in diagnosing the causes of exercise-induced leg pain. It is useful in identifying CACS with and without comorbidity.

Changes in Muscle Oxygen Saturation Have Low Sensitivity in Diagnosing Chronic Anterior Compartment Syndrome of the Leg.

BACKGROUND: Near-infrared spectroscopy measures muscle oxygen saturation (StO2) in the skeletal muscle and has been proposed as a noninvasive tool for diagnosing chronic anterior compartment syndrome (CACS). The purpose of this study was to investigate the diagnostic value of changes in StO2 during and after exercise in patients with CACS. METHODS: The study comprised 159 consecutive patients with exercise-induced leg pain. Near-infrared spectroscopy was used to measure StO2 continuously before, during, and after an exercise test. One minute post-exercise, intramuscular pressure was recorded in the same muscle. The cohort was divided into patients with CACS (n = 87) and patients without CACS (n = 72) according to the CACS diagnostic criteria. Reoxygenation at rest after exercise was calculated as the time period required for the level of muscular StO2 to reach 50% (T50), 90% (T90), and 100% (T100) of the baseline value. RESULTS: The lowest level of StO2 during exercise was 1% (range, 1% to 36%) in the patients with CACS and 3% (range, 1% to 54%) in the patients without CACS. The sensitivity was 34% and the specificity was 43% when an StO2 level of ≤8% at peak exercise was used to indicate CACS. The sensitivity and the specificity were only 1% when an StO2 level of ≤50% at peak exercise was used to indicate CACS. The time period for reoxygenation was seven seconds (range, one to forty-three seconds) at T50, twenty-eight seconds (range, seven to seventy-seven seconds) at T90, and forty-two seconds (range, seven to 200 seconds) at T100 in the patients with CACS and ten seconds (range, one to forty-nine seconds) at T50, thirty-two seconds (range, four to 138 seconds) at T90, and forty-eight seconds (range, four to 180 seconds) at T100 in the patients without CACS. When thirty seconds or more at T90 was set as the cutoff value for a prolonged time for reoxygenation, indicating a diagnosis of CACS, the sensitivity was 38% and the specificity was 50%. CONCLUSIONS: Changes in muscle oxygen saturation during and after an exercise test that elicits leg pain cannot be used to distinguish between patients with CACS and patients with other causes of exercise-induced leg pain.