SPORT MEDICINE JOURNAL CLUB Journal Club Editor: Lawrence Hart, MBBCh, MSc, FRCPC Editorial Associate: Ann Lotter, BA Journal Club highlights recent studies in sport medicine that meet criteria for methodological rigor and clinical relevance. Selected articles are formatted as structured abstracts and published with accompanying expert commentaries.
Is Intramuscular Pressure a Valid Diagnostic Criterion for Chronic Exertional Compartment Syndrome? This CJSM Journal Club contribution provides a commentary on the following article: Roberts A, Franklyn-Miller A. The validity of the diagnostic criteria used in chronic exertional compartment syndrome: a systematic review. Scand J Med Sci Sports. 2012;24:87– 595.
Overview of Original Article Objective: To compare the intramuscular pressure (IMP) of the tibialis anterior in healthy persons under several exercise conditions with the IMP diagnostic criteria in use for diagnosing chronic exertional compartment syndrome (CECS). Data Sources: A search of MEDLINE for the period 1966 to March 2010 used the words “intramuscular,” “intracompartment,” “anterior compartment,” and “anterior tibial compartment” linked with “pressure.” Reference lists of relevant studies were searched for further articles. Study Selection: Articles published in English that tested IMP in the tibialis anterior in asymptomatic humans were included if they used no interventions before or during IMP testing. Studies were excluded if data were given as a percentage of IMP or if the data could not be extracted for the tibialis anterior compartment alone. From 515 articles identified, 38 studies met selection criteria Data Extraction: Details of the studies included IMP measurement technique, Source of funding for the original study: Not stated. Correspondence about the original article: Andrew Roberts, MSc, Centre for Human Performance, Rehabilitation and Sports Medicine, Defence Medical Rehabilitation Centre, Headley Court, Epsom, Surrey KT18 6JW, United Kingdom ([email protected]).
timing of measurement (before, during, and/or after exercise), type and duration of exercise, the number of compartments measured, and participants’ ages. Mean or median pressure was recorded in mm Hg. Diagnostic Standard: Criteria for the upper limit of normal pressure under different conditions were the Pedowitz criterion for preexercise IMP (15 mm Hg), the Puranen criterion for IMP during exercise (50 mm Hg), the Styf criterion for relaxation pressure (30-55 mm Hg), and the Pedowitz criteria for mean 1-minute postexercise and 5-minutes postexercise pressures (30 mm Hg and 50 mm Hg, respectively). Main Results: Exercise was mostly treadmill walking/running (duration, 1.5120 min) or ankle dorsiflexion (duration, 10 sec-20 min). Methods of measuring IMP varied from study to study. The lowest mean IMP was identified preexercise at rest (range, 0-20 mm Hg). Five of the 34 studies found a higher mean resting pressure than the criterion (15 mm Hg). Mean pressure during exercise (10 studies, 9 of running, with durations of 5-20 min) varied between 23 mm Hg and 66 mm Hg. Two of these studies found a higher mean peak pressure during exercise than the criterion (50 mm Hg). Mean relaxation IMP, measured in 9 studies, was approximately 25 mm Hg in the 1 treadmill study in which it was measured, whereas studies of dorsiflexion found a range of approximately 5 to 15 mm Hg. All the studies found lower mean relaxation IMP than the criterion (35-50 mm Hg). One of 11 studies and 1 of 10 studies found the mean postexercise IMP after 1 minute and 5 minutes to be above the criteria of 30 mm Hg and 20 mm Hg, respectively. Conclusions: The limits of anterior tibialis IMP before, during, and after exercise that are used as diagnostic criteria for CECS would include many asymptomatic persons. Intramuscular pressure values were not valid criteria for the presence of the syndrome.
Clin J Sport Med Volume 24, Number 1, January 2014
Commentary The review by Roberts and Franklyn-Miller is important because it makes clear the limitations and potential pitfalls of current diagnostic criteria for exertional compartment syndrome (CECS) and it makes useful recommendations in this regard. The emphasis of the review is on the large number of potentially confounding issues that can greatly increase the variability of intramuscular pressure (IMP) measurements and thus significantly affect the degree of certainty with which CECS can be diagnosed by this method. Specifically, the review noted that the depth and angle of catheter implantation in muscle needs to be standardized in clinical settings. The authors suggested that deeper portions of the muscle may provide information that is more reliable. They also noted that the only reliable data currently available are for the anterior part of the lower leg (tibialis anterior) and that the diagnostic criteria cannot be reliably applied to any other muscle group. In addition, runningshoe type and running technique used by the participants could have confounding effects on IMP measurements. The type and sensitivity of the catheter used in making the measurements also produced variable IMP results. The reviewed studies suggest that it is likely that a substantial and possibly natural overlap in IMP may occur during exercise between the range for the normal asymptomatic population and the range for patients who are suspected of having CECS because of their exercise-induced lower limb pain. Thus, in addition to the inherent dangers of variability in the measurement of IMP, there may also be an unacceptably large number of false positive diagnoses because of this overlap. Roberts and Franklyn-Miller suggest that current diagnostic criteria for CECS should not be used to make a definitive diagnosis, but that patients with chronic exerciseinduced lower leg pain should only be www.cjsportmed.com |
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diagnosed with CECS when comparisons are made using a standard protocol and data from asymptomatic subjects and, preferably, using data on asymptomatic subjects gathered within the treating clinic. In the context of possible misdiagnosis of CECS, an initial treatment should encourage subjects to alter running patterns to a forefoot-strike movement, although this intervention may be difficult for clinicians to implement successfully. Conservative treatment would, however, avoid the possibility of failed fasciectomy. It may be that the reported frequent failure rate of fasciectomy as a treatment for CECS1 may be due, in part, to ignoring more conservative treatments and to misdiagnosis of the syndrome, possibly because the diagnostic criteria discussed in this review were used. Peter M. Tiidus, PhD Health Sciences Program and Department of Kinesiology Wilfrid Laurier University Waterloo, Ontario, Canada
REFERENCE 1. Slimmon D, Bennell K, Brukner P, et al. Longterm outcome of fasciotomy with partial fasciectomy for chronic exertional compartment syndrome of the lower leg. Am J Sports Med. 2002;30:581–588.
Comparing PRP Injections With ESWT for Athletes With Chronic Patellar Tendinopathy This CJSM Journal Club contribution provides a commentary on the following article: Vetrano M, Castorina A, Vulpiani MC, et al. Platelet-rich plasma versus focused shock waves in the treatment of jumper’s knee in athletes. Am J Sports Med. 2013;24:89–803.
Overview of Original Article Objective: To compare the effectiveness of injections of platelet-rich plasma Source of funding for the original study: No external funding. Correspondence about the original article: Mario Vetrano, MD, Physical Medicine and Rehabilitation Unit, Sant’Andrea Hospital, Via di Grottarossa 1035-1039, Rome 00189, Italy ([email protected]).
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Clin J Sport Med Volume 24, Number 1, January 2014
(PRP) compared with focused extracorporeal shock-wave therapy (ESWT) among athletes with chronic patellar tendinopathy (jumper’s knee). Design: Randomized controlled singlecenter trial, with 12 months of follow-up. Setting: Tertiary-level care in Rome, Italy. Patients were recruited from January 2009 to May 2011. Participants: Patients who received a diagnosis of jumper’s knee from a participating physician were recruited into the study (n = 46). Inclusion criteria were chronic ($6 months), unilateral, proximal patellar tendinopathy in a recreational or elite athlete confirmed by ultrasound (US); prior failed nonoperative management that concluded $12 weeks prior to study entry; and ages 18 to 50 years. Exclusion criteria were coexisting knee lesions, systemic disorders, knee surgery or corticosteroid injection in the previous 3 months, and contraindications to PRP treatment. Intervention: Patients in the PRP group (n = 23) received 2 US-guided injections separated by 1 week and directed at the affected tendon portion. Each injection consisted of 2 mL of nonactivated, autologous PRP extracted from a single centrifugation of 10-mL blood and administered by a trained physician via a 22-guage needle. Patients in the focused ESWT group (n = 23) received 3 treatments (2400 impulses at 0.17-0.25 mJ/mm2 per session) separated by 48 to 72 hours. Treatments were guided by inline US and administered by 1 experienced operator. No local anesthesia was used in either group. One week later, both groups began a conventional stretching and strengthening program for 2 weeks. At 4 weeks, patients gradually resumed normal activities and sports, as tolerated. Main Outcome Measures: At 2, 6, and 12 months after treatment, patients were assessed by a single investigator, blinded to group assignment. The main measure was the Italian version of the Victorian Institute of Sports Assessment-Patella (VISA-P) questionnaire, which evaluates severity of symptoms, function, and ability to participate in sport. A 10-cm visual analog scale (VAS) was used to assess pain while doing 5 single-leg squats. Patients also assessed their response to treatment on
the Blazina scale (excellent to poor). No patients were lost to follow-up Main Results: During the 12-month follow-up period, VISA-P scores for both groups improved significantly from baseline (55.3 for PRP, 56.1 for ESWT), although the PRP group had greater improvement at 6 months (86.7 vs 73.7; P = 0.014) and 12 months (91.3 vs 77.6; P = 0.026). Pain scores during 5 singleleg squats demonstrated similar findings. At 12 months a greater proportion of patients in the PRP group rated their response to treatment as good or excellent (PRP, 91.3% vs ESWT, 60.8%; P = 0.035), although at earlier follow-ups the groups did not differ. Both the injections and ESWT caused transient discomfort. No patient had surgery during follow-up. Conclusions: Athletes with chronic patellar tendinopathy responded positively to both PRP injection and ESWT. However, the PRP-treated patients demonstrated significantly greater improvements in VISA-P and pain scores by 6 months and significantly better functional outcomes and satisfaction based on a modified Blazina scale, at 12 months.
Commentary Proximal patellar tendinopathy can be a challenging condition to treat, as evidenced by the plethora of currently available interventions, including activity modification, bracing, therapeutic exercise, neovessel ablation, tendon scraping, percutaneous tenotomy, ESWT, and emerging biologic therapies such as injections of PRP, tenocytes, and various stem cell vehicles.1 Unfortunately, there is a paucity of well-designed clinical trials guiding best practices in treating this condition.1 Vetrano et al report on a well-designed, prospective, randomized study comparing ESWT and PRP in an active population. Patient selection, treatments, and follow-up were standardized, and the clinician who evaluated outcomes was blinded to treatment group. Although both groups improved during the 12month follow-up, the PRP group improvement was significantly greater, at 6 and 12 months, in VISA-P and pain during single-leg squats and, at 12 months, in patient self-reported outcome based on the modified Blazina scale. There were no complications, and the 100% follow-up in both groups is commendable. The authors concluded that Ó 2014 Lippincott Williams & Wilkins
Is Intramuscular Pressure a Valid Diagnostic Criterion for Chronic Exertional Compartment Syndrome? This CJSM Journal Club contribution provides a commentary on the following article: Roberts A, Franklyn-Miller A. The validity of the diagnostic criteria used in chronic exertional compartment syndrome: a systematic review. Scand J Med Sci Sports. 2012;24:87– 595.
Overview of Original Article Objective: To compare the intramuscular pressure (IMP) of the tibialis anterior in healthy persons under several exercise conditions with the IMP diagnostic criteria in use for diagnosing chronic exertional compartment syndrome (CECS). Data Sources: A search of MEDLINE for the period 1966 to March 2010 used the words “intramuscular,” “intracompartment,” “anterior compartment,” and “anterior tibial compartment” linked with “pressure.” Reference lists of relevant studies were searched for further articles. Study Selection: Articles published in English that tested IMP in the tibialis anterior in asymptomatic humans were included if they used no interventions before or during IMP testing. Studies were excluded if data were given as a percentage of IMP or if the data could not be extracted for the tibialis anterior compartment alone. From 515 articles identified, 38 studies met selection criteria Data Extraction: Details of the studies included IMP measurement technique, Source of funding for the original study: Not stated. Correspondence about the original article: Andrew Roberts, MSc, Centre for Human Performance, Rehabilitation and Sports Medicine, Defence Medical Rehabilitation Centre, Headley Court, Epsom, Surrey KT18 6JW, United Kingdom ([email protected]).
timing of measurement (before, during, and/or after exercise), type and duration of exercise, the number of compartments measured, and participants’ ages. Mean or median pressure was recorded in mm Hg. Diagnostic Standard: Criteria for the upper limit of normal pressure under different conditions were the Pedowitz criterion for preexercise IMP (15 mm Hg), the Puranen criterion for IMP during exercise (50 mm Hg), the Styf criterion for relaxation pressure (30-55 mm Hg), and the Pedowitz criteria for mean 1-minute postexercise and 5-minutes postexercise pressures (30 mm Hg and 50 mm Hg, respectively). Main Results: Exercise was mostly treadmill walking/running (duration, 1.5120 min) or ankle dorsiflexion (duration, 10 sec-20 min). Methods of measuring IMP varied from study to study. The lowest mean IMP was identified preexercise at rest (range, 0-20 mm Hg). Five of the 34 studies found a higher mean resting pressure than the criterion (15 mm Hg). Mean pressure during exercise (10 studies, 9 of running, with durations of 5-20 min) varied between 23 mm Hg and 66 mm Hg. Two of these studies found a higher mean peak pressure during exercise than the criterion (50 mm Hg). Mean relaxation IMP, measured in 9 studies, was approximately 25 mm Hg in the 1 treadmill study in which it was measured, whereas studies of dorsiflexion found a range of approximately 5 to 15 mm Hg. All the studies found lower mean relaxation IMP than the criterion (35-50 mm Hg). One of 11 studies and 1 of 10 studies found the mean postexercise IMP after 1 minute and 5 minutes to be above the criteria of 30 mm Hg and 20 mm Hg, respectively. Conclusions: The limits of anterior tibialis IMP before, during, and after exercise that are used as diagnostic criteria for CECS would include many asymptomatic persons. Intramuscular pressure values were not valid criteria for the presence of the syndrome.
Clin J Sport Med Volume 24, Number 1, January 2014
Commentary The review by Roberts and Franklyn-Miller is important because it makes clear the limitations and potential pitfalls of current diagnostic criteria for exertional compartment syndrome (CECS) and it makes useful recommendations in this regard. The emphasis of the review is on the large number of potentially confounding issues that can greatly increase the variability of intramuscular pressure (IMP) measurements and thus significantly affect the degree of certainty with which CECS can be diagnosed by this method. Specifically, the review noted that the depth and angle of catheter implantation in muscle needs to be standardized in clinical settings. The authors suggested that deeper portions of the muscle may provide information that is more reliable. They also noted that the only reliable data currently available are for the anterior part of the lower leg (tibialis anterior) and that the diagnostic criteria cannot be reliably applied to any other muscle group. In addition, runningshoe type and running technique used by the participants could have confounding effects on IMP measurements. The type and sensitivity of the catheter used in making the measurements also produced variable IMP results. The reviewed studies suggest that it is likely that a substantial and possibly natural overlap in IMP may occur during exercise between the range for the normal asymptomatic population and the range for patients who are suspected of having CECS because of their exercise-induced lower limb pain. Thus, in addition to the inherent dangers of variability in the measurement of IMP, there may also be an unacceptably large number of false positive diagnoses because of this overlap. Roberts and Franklyn-Miller suggest that current diagnostic criteria for CECS should not be used to make a definitive diagnosis, but that patients with chronic exerciseinduced lower leg pain should only be www.cjsportmed.com |
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diagnosed with CECS when comparisons are made using a standard protocol and data from asymptomatic subjects and, preferably, using data on asymptomatic subjects gathered within the treating clinic. In the context of possible misdiagnosis of CECS, an initial treatment should encourage subjects to alter running patterns to a forefoot-strike movement, although this intervention may be difficult for clinicians to implement successfully. Conservative treatment would, however, avoid the possibility of failed fasciectomy. It may be that the reported frequent failure rate of fasciectomy as a treatment for CECS1 may be due, in part, to ignoring more conservative treatments and to misdiagnosis of the syndrome, possibly because the diagnostic criteria discussed in this review were used. Peter M. Tiidus, PhD Health Sciences Program and Department of Kinesiology Wilfrid Laurier University Waterloo, Ontario, Canada
REFERENCE 1. Slimmon D, Bennell K, Brukner P, et al. Longterm outcome of fasciotomy with partial fasciectomy for chronic exertional compartment syndrome of the lower leg. Am J Sports Med. 2002;30:581–588.
Comparing PRP Injections With ESWT for Athletes With Chronic Patellar Tendinopathy This CJSM Journal Club contribution provides a commentary on the following article: Vetrano M, Castorina A, Vulpiani MC, et al. Platelet-rich plasma versus focused shock waves in the treatment of jumper’s knee in athletes. Am J Sports Med. 2013;24:89–803.
Overview of Original Article Objective: To compare the effectiveness of injections of platelet-rich plasma Source of funding for the original study: No external funding. Correspondence about the original article: Mario Vetrano, MD, Physical Medicine and Rehabilitation Unit, Sant’Andrea Hospital, Via di Grottarossa 1035-1039, Rome 00189, Italy ([email protected]).
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| www.cjsportmed.com
Clin J Sport Med Volume 24, Number 1, January 2014
(PRP) compared with focused extracorporeal shock-wave therapy (ESWT) among athletes with chronic patellar tendinopathy (jumper’s knee). Design: Randomized controlled singlecenter trial, with 12 months of follow-up. Setting: Tertiary-level care in Rome, Italy. Patients were recruited from January 2009 to May 2011. Participants: Patients who received a diagnosis of jumper’s knee from a participating physician were recruited into the study (n = 46). Inclusion criteria were chronic ($6 months), unilateral, proximal patellar tendinopathy in a recreational or elite athlete confirmed by ultrasound (US); prior failed nonoperative management that concluded $12 weeks prior to study entry; and ages 18 to 50 years. Exclusion criteria were coexisting knee lesions, systemic disorders, knee surgery or corticosteroid injection in the previous 3 months, and contraindications to PRP treatment. Intervention: Patients in the PRP group (n = 23) received 2 US-guided injections separated by 1 week and directed at the affected tendon portion. Each injection consisted of 2 mL of nonactivated, autologous PRP extracted from a single centrifugation of 10-mL blood and administered by a trained physician via a 22-guage needle. Patients in the focused ESWT group (n = 23) received 3 treatments (2400 impulses at 0.17-0.25 mJ/mm2 per session) separated by 48 to 72 hours. Treatments were guided by inline US and administered by 1 experienced operator. No local anesthesia was used in either group. One week later, both groups began a conventional stretching and strengthening program for 2 weeks. At 4 weeks, patients gradually resumed normal activities and sports, as tolerated. Main Outcome Measures: At 2, 6, and 12 months after treatment, patients were assessed by a single investigator, blinded to group assignment. The main measure was the Italian version of the Victorian Institute of Sports Assessment-Patella (VISA-P) questionnaire, which evaluates severity of symptoms, function, and ability to participate in sport. A 10-cm visual analog scale (VAS) was used to assess pain while doing 5 single-leg squats. Patients also assessed their response to treatment on
the Blazina scale (excellent to poor). No patients were lost to follow-up Main Results: During the 12-month follow-up period, VISA-P scores for both groups improved significantly from baseline (55.3 for PRP, 56.1 for ESWT), although the PRP group had greater improvement at 6 months (86.7 vs 73.7; P = 0.014) and 12 months (91.3 vs 77.6; P = 0.026). Pain scores during 5 singleleg squats demonstrated similar findings. At 12 months a greater proportion of patients in the PRP group rated their response to treatment as good or excellent (PRP, 91.3% vs ESWT, 60.8%; P = 0.035), although at earlier follow-ups the groups did not differ. Both the injections and ESWT caused transient discomfort. No patient had surgery during follow-up. Conclusions: Athletes with chronic patellar tendinopathy responded positively to both PRP injection and ESWT. However, the PRP-treated patients demonstrated significantly greater improvements in VISA-P and pain scores by 6 months and significantly better functional outcomes and satisfaction based on a modified Blazina scale, at 12 months.
Commentary Proximal patellar tendinopathy can be a challenging condition to treat, as evidenced by the plethora of currently available interventions, including activity modification, bracing, therapeutic exercise, neovessel ablation, tendon scraping, percutaneous tenotomy, ESWT, and emerging biologic therapies such as injections of PRP, tenocytes, and various stem cell vehicles.1 Unfortunately, there is a paucity of well-designed clinical trials guiding best practices in treating this condition.1 Vetrano et al report on a well-designed, prospective, randomized study comparing ESWT and PRP in an active population. Patient selection, treatments, and follow-up were standardized, and the clinician who evaluated outcomes was blinded to treatment group. Although both groups improved during the 12month follow-up, the PRP group improvement was significantly greater, at 6 and 12 months, in VISA-P and pain during single-leg squats and, at 12 months, in patient self-reported outcome based on the modified Blazina scale. There were no complications, and the 100% follow-up in both groups is commendable. The authors concluded that Ó 2014 Lippincott Williams & Wilkins
