High-Resolution CT Grading of Tibial Stress Reactions in Distance Runners

Diagnostic Accuracy of Dual-Energy CT for Bone Stress Injury of the Lower Limb

Background Because of its ability to help assess the presence of subtle morphologic changes in bone and bone marrow edema, dual-energy CT (DECT) could be an alternative to MRI in the diagnosis of bone stress injury that includes a stress fracture (SF) and stress reaction (SR). Purpose To determine the diagnostic accuracy of DECT in identifying bone stress injury of the lower limb using MRI as the reference standard. Materials and Methods This prospective study, conducted between June 2021 and January 2024, included consecutive patients clinically suspected of having stress injury (SF or SR) of the lower limb (leg, ankle, or foot). Imaging diagnosis was based on the absence or presence of cortical or periosteal changes, bone marrow edema, or a fracture line. The diagnostic performance of four blinded independent readers was determined for the entire cohort and for the subset of participants without fracture lines. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated. Interobserver agreement was evaluated with Kendall coefficient of concordance (W). Results A total of 184 patients (mean age, 58 years ± 17 [SD]; 97 male) were enrolled. At MRI, 107 of 184 participants (58%) had positive diagnoses, including 70 with SF and 37 with SR. The mean overall sensitivity and specificity were 91% (390 of 428; 95% CI: 0.85, 0.95) and 93% (287 of 308; 95% CI: 0.87, 0.97), respectively, with an AUC of 0.94 (95% CI: 0.91, 0.97). Among patients without fracture lines (n = 114), the mean overall sensitivity and specificity of DECT were 79% (117 of 148; 95% CI: 0.65, 0.88) and 93% (287 of 308; 95% CI: 0.87, 0.97), respectively, with an AUC of 0.87 (95% CI: 0.81, 0.94). The interobserver agreement was very good for diagnosis of SF and SR combined (Kendall W = 0.90) and SR alone (Kendall W = 0.84). Conclusion DECT helped to accurately diagnose bone stress injury of the lower limb by identifying fracture lines and osseous stress reactions. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Breighner in this issue.

The Effect of Inflammation on Bone

Bone remodeling is the continual process to renew the adult skeleton through the sequential action of osteoblasts and osteoclasts. Nuclear factor RANK, an osteoclast receptor, and its ligand RANKL, expressed on the surface of osteoblasts, result in coordinated control of bone remodeling. Inflammation, a feature of illness and injury, plays a distinct role in skewing this process toward resorption. It does so via the interaction of inflammatory mediators and their related peptides with osteoblasts and osteoclasts, as well as other immune cells, to alter the expression of RANK and RANKL. Such chemical mediators include TNFα, glucocorticoids, histamine, bradykinin, PGE2, systemic RANKL from immune cells, and interleukins 1 and 6. Conditions, such as periodontal disease and alveolar bone erosion, aseptic prosthetic loosening, rheumatoid arthritis, and some sports related injuries are characterized by the result of this process. A thorough understanding of bone response to injury and disease, and ability to detect such biomarkers, as well as imaging to identify early structural and mechanical property changes in bone architecture, is important in improving management and outcomes of bone related pathology. While gut health and vitamin and mineral availability appear vitally important, nutraceuticals also have an impact on bone health. To date most pharmaceutical intervention targets inflammatory cytokines, although strategies to favorably alter inflammation induced bone pathology are currently limited. Further research is required in this field to advance early detection and treatments.

Bilateral Looser zones or pseudofractures in the anteromedial tibia as a component of medial tibial stress syndrome in athletes

PURPOSE

Medial tibial stress syndrome (MTSS) represents a common diagnosis in individuals exposed to repetitive high-stress loads affecting the lower limb, e.g., high-performance athletes. However, the diagnostic approach and therapeutic regimens are not well established.

METHODS

Nine patients, diagnosed as MTSS, were analyzed by a comprehensive skeletal analysis including laboratory bone turnover parameters, dual-energy X-Ray absorptiometry (DXA), and high-resolution peripheral quantitative computed tomography (HR-pQCT).

RESULTS

In 4/9 patients, bilateral pseudofractures were detected in the mid-shaft tibia. These patients had significantly lower levels of 25-hydroxycholecalciferol compared to patients with MTSS but similar levels of bone turnover parameters. Interestingly, the skeletal assessment revealed significantly higher bone mineral density (BMD) Z-scores at the hip (1.3 ± 0.6 vs. - 0.7 ± 0.5, p = 0.013) in patients with pseudofractures and a trend towards higher bone microarchitecture parameters measured by HR-pQCT at the distal tibia. Vitamin D supplementation restored the calcium-homeostasis in all patients. Combined with weight-bearing as tolerated, pseudofractures healed in all patients and return to competition was achieved.

CONCLUSION

In conclusion, deficient vitamin D levels may lead to pseudofractures due to localized deterioration of mineralization, representing a pivotal component of MTSS in athletes with increased repetitive mechanical loading of the lower limbs. Moreover, the manifestation of pseudofractures is not a consequence of an altered BMD nor microarchitecture but appears in patients with exercise-induced BMD increase in combination with reduced 25-OH-D levels. The screening of MTSS patients for pseudofractures is crucial for the initiation of an appropriate treatment such as vitamin D supplementation to prevent a prolonged course of healing or recurrence.

LEVEL OF EVIDENCE

III.

Medial Tibial Stress Syndrome in Novice and Recreational Runners: A Systematic Review

This systematic review evaluates the existing literature about medial tibial stress syndrome (MTSS) in novice and recreational runners. PubMed/MEDLINE, EMBASE, Web of Science, Scopus, SPORTDiscus and CINAHL databases were searched until July 2020. Studies covering risk factors, diagnostic procedures, treatment methods and time to recovery of MTSS in novice and recreational runners were selected. Eleven studies met the inclusion criteria and were included. The risk factors of MTSS are mainly intrinsic and include higher pelvic tilt in the frontal plane, peak internal rotation of the hip, navicular drop and foot pronation, among others. Computed tomography (CT) and pressure algometry may be valid instruments to corroborate the presence of this injury and confirm the diagnosis. Regarding treatment procedures, arch-support foot orthoses are able to increase contact time, normalize foot pressure distribution and similarly to shockwave therapy, reduce pain. However, it is important to take into account the biases and poor methodological quality of the included studies, more research is needed to confirm these results.

A Clinically Driven Task-Based Comparison of Photon Counting and Conventional Energy Integrating CT for Soft Tissue, Vascular, and High-Resolution Tasks

Photon-counting CT detectors are the next step in advancing CT system development and will replace the current energy integrating detectors (EID) in CT systems in the near future. In this context, the performance of PCCT was compared to EID CT for three clinically relevant tasks: abdominal soft tissue imaging, where differentiating low contrast features is important; vascular imaging, where iodine detectability is critical; and, high-resolution skeletal and lung imaging. A multi-tiered phantom was imaged on an investigational clinical PCCT system (Siemens Healthineers) across different doses using three imaging modes: macro and ultra-high resolution (UHR) PCCT modes and EID CT. Images were reconstructed using filtered backprojection and soft tissue (B30f), vascular (B46f), or high-resolution (B70f; U70f for UHR) kernels. Noise power spectra, task transfer functions, and detectability index were evaluated. For a soft tissue task, PCCT modes showed comparable noise and resolution with improved contrast-to-noise ratio. For a vascular task, PCCT modes showed lower noise and improved iodine detectability. For a high resolution task, macro mode showed lower noise and comparable resolution while UHR mode showed higher noise but improved spatial resolution for both air and bone. PCCT offers competitive advantages to EID CT for clinical tasks.

VIBE MRI: an alternative to CT in the imaging of sports-related osseous pathology?

MRI is an excellent diagnostic tool in the imaging of sports-related musculoskeletal pathology; however, standard slice thickness acquisitions can lack the spatial resolution to accurately define and characterise osseous abnormalities. Standard MRI sequences may be supplemented with CT to reduce diagnostic uncertainty. We provide a clinical perspective, in the form of pictorial review, on the potential applications of 3D MRI sequences, specifically using volumetric interpolated breath-hold examination in the characterisation of various musculoskeletal osseous pathologies. The potential to negate the requirement for CT in a young radiation sensitive cohort is a clinically significant concept and suggests the requirement for further studies comparing the performance of volumetric MRI to CT.

Expected Time to Return to Athletic Participation After Stress Fracture in Division I Collegiate Athletes

BACKGROUND

Few studies have documented expected time to return to athletic participation after stress fractures in elite athletes.

HYPOTHESIS

Time to return to athletic participation after stress fractures would vary by site and severity of stress fracture.

STUDY DESIGN

Retrospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

All stress fractures diagnosed in a single Division I collegiate men's and women's track and field/cross-country team were recorded over a 3-year period. Site and severity of injury were graded based on Kaeding-Miller classification system for stress fractures. Time to return to full unrestricted athletic participation was recorded for each athlete and correlated with patient sex and site and severity grade of injury.

RESULTS

Fifty-seven stress fractures were diagnosed in 38 athletes (mean age, 20.48 years; range, 18-23 years). Ten athletes sustained recurrent or multiple stress fractures. Thirty-seven injuries occurred in women and 20 in men. Thirty-three stress fractures occurred in the tibia, 10 occurred in the second through fourth metatarsals, 3 occurred in the fifth metatarsal, 6 in the tarsal bones (2 navicular), 2 in the femur, and 5 in the pelvis. There were 31 grade II stress fractures, 11 grade III stress fractures, and 2 grade V stress fractures (in the same patient). Mean time to return to unrestricted sport participation was 12.9 ± 5.2 weeks (range, 6-27 weeks). No significant differences in time to return were noted based on injury location or whether stress fracture was grade II or III.

CONCLUSION

The expected time to return to full unrestricted athletic participation after diagnosis of a stress fracture is 12 to 13 weeks for all injury sites.

CLINICAL RELEVANCE

Athletes with grade V (nonunion) stress fractures may require more time to return to sport.

Shockwave treatment for medial tibial stress syndrome in military cadets: A single-blind randomized controlled trial

Medial tibial stress syndrome (MTSS) is a common injury in athletes and soldiers. Several studies have demonstrated the effectiveness of extracorporeal shockwave treatment (ESWT) in athletes with MTSS.

OBJECTIVE

To assess whether one session of focused ESWT is effective in the treatment of military cadets with MTSS.

DESIGN

A randomized, prospective, controlled, single-blind, parallel-group clinical study.

LEVEL OF EVIDENCE

Ib.

SETTING

Military School of Cadets of the Colombian Army.

METHODS

Forty-two military cadets with unilateral chronic MTSS were randomly assigned to either one session of focused electromagnetic ESWT (1500 pulses at 0.20 mJ/mm²) plus a specific exercise programme (muscle stretching and strengthening exercises) or the exercise programme alone. The primary endpoint was change in asymptomatic running test (RT) duration at four weeks from baseline. Secondary endpoints were changes in the visual analogue scale (VAS) after running and modified Roles and Maudsley (RM) score also at four weeks from baseline.

RESULTS

ESWT patients were able to run longer. Mean RT after four weeks was 17 min 33 s (SE: 2.36) compared to 4 min 48 s (SE: 1.03) in the exercise-only group (p = 0.000). Mean VAS after running was 2.17 (SE: 0.44) in the ESWT group versus 4.26 (SE: 0.36) in the exercise-only group (p = 0.001). The ESWT group had a significantly higher RM score, with excellent or good results for 82.6% of patients vs. 36.8% in the exercise-only group (p = 0.002). No significant adverse effects of ESWT were observed.

CONCLUSION

A single application of focused shockwave treatment in combination with a specific exercise programme accelerates clinical and functional recovery in military cadets with MTSS.

Medial Tibial Stress Syndrome in Active Individuals: A Systematic Review and Meta-analysis of Risk Factors

CONTEXT

Medial tibial stress syndrome (MTSS) is a common condition in active individuals and presents as diffuse pain along the posteromedial border of the tibia.

OBJECTIVE

To use cross-sectional, case-control, and cohort studies to identify significant MTSS risk factors.

DATA SOURCES

Bibliographic databases (PubMed, Scopus, CINAHL, SPORTDiscus, EMBASE, EBM Reviews, PEDRo), grey literature, electronic search of full text of journals, manual review of reference lists, and automatically executed PubMed MTSS searches were utilized. All searches were conducted between 2011 and 2015.

STUDY SELECTION

Inclusion criteria were determined a priori and included original research with participants' pain diffuse, located in the posterior medial tibial region, and activity related.

STUDY DESIGN

Systematic review with meta-analysis.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Titles and abstracts were reviewed to eliminate citations that did not meet the criteria for inclusion. Study characteristics identified a priori were extracted for data analysis. Statistical heterogeneity was examined using the I2 index and Cochran Q test, and a random-effects model was used to calculate the meta-analysis when 2 or more studies examined a risk factor. Two authors independently assessed study quality.

RESULTS

Eighty-three articles met the inclusion criteria, and 22 articles included risk factor data. Of the 27 risk factors that were in 2 or more studies, 5 risk factors showed a significant pooled effect and low statistical heterogeneity, including female sex (odds ratio [OR], 2.35; CI, 1.58-3.50), increased weight (standardized mean difference [SMD], 0.24; CI, 0.03-0.45), higher navicular drop (SMD, 0.44; CI, 0.21-0.67), previous running injury (OR, 2.18; CI, 1.00-4.72), and greater hip external rotation with the hip in flexion (SMD, 0.44; CI, 0.23-0.65). The remaining risk factors had a nonsignificant pooled effect or significant pooled effect with high statistical heterogeneity.

CONCLUSION

Female sex, increased weight, higher navicular drop, previous running injury, and greater hip external rotation with the hip in flexion are risk factors for the development of MTSS.

Taking a holistic approach to managing difficult stress fractures

Stress fractures and other bony stress injuries occur along a spectrum of severity which can impact treatment and prognosis. When treating these injuries, it should be borne in mind that no two stress fractures behave exactly alike. Given that they are not a consistent injury, standardized treatment protocols can be challenging to develop. Treatment should be individualized to the patient or athlete, the causative activity, the anatomical site, and the severity of the injury. A holistic approach to the treatment of the most difficult stress fractures should be taken by orthopedists and sports medicine specialists. This approach is necessary to obtain optimal outcomes, minimize loss of fitness and time away from sports participation, and decrease the risk of recurrence.

Chronic leg pain in athletes

Chronic leg pain is commonly treated by orthopaedic surgeons who take care of athletes. The sources are varied and include the more commonly encountered medial tibial stress syndrome, chronic exertional compartment syndrome, stress fracture, popliteal artery entrapment syndrome, nerve entrapment, Achilles tightness, deep vein thrombosis, and complex regional pain syndrome. Owing to overlapping physical examination findings, an assortment of imaging and other diagnostic modalities are employed to distinguish among the diagnoses to guide the appropriate management. Although most of these chronic problems are treated nonsurgically, some patients require operative intervention. For each condition listed above, the pathophysiology, diagnosis, management option, and outcomes are discussed in turn.

Tibial cortical lesions: a multimodality pictorial review

Shin pain is a common complaint, particularly in young and active patients, with a wide range of potential diagnoses and resulting implications. We review the natural history and multimodality imaging findings of the more common causes of cortically-based tibial lesions, as well as the rarer pathologies less frequently encountered in a general radiology department.

Management and prevention of bone stress injuries in long-distance runners

SYNOPSIS

Bone stress injury (BSI) represents the inability of bone to withstand repetitive loading, which results in structural fatigue and localized bone pain and tenderness. A BSI occurs along a pathology continuum that begins with a stress reaction, which can progress to a stress fracture and, ultimately, a complete bone fracture. Bone stress injuries are a source of concern in long-distance runners, not only because of their frequency and the morbidity they cause but also because of their tendency to recur. While most BSIs readily heal following a period of modified loading and a progressive return to running activities, the high recurrence rate of BSIs signals a need to address their underlying causative factors. A BSI results from disruption of the homeostasis between microdamage formation and its removal. Microdamage accumulation and subsequent risk for development of a BSI are related both to the load applied to a bone and to the ability of the bone to resist load. The former is more amenable to intervention and may be modified by interventions aimed at training-program design, reducing impact-related forces (eg, instructing an athlete to run "softer" or with a higher stride rate), and increasing the strength and/or endurance of local musculature (eg, strengthening the calf for tibial BSIs and the foot intrinsics for BSIs of the metatarsals). Similarly, malalignments and abnormal movement patterns should be explored and addressed. The current commentary discusses management and prevention of BSIs in runners. In doing so, information is provided on the pathophysiology, epidemiology, risk factors, clinical diagnosis, and classification of BSIs.

LEVEL OF EVIDENCE

Therapy, level 5.

Treatment of medial tibial stress syndrome: a systematic review

BACKGROUND

Medial tibial stress syndrome (MTSS) is a common exercise-induced leg injury among athletes and military personnel. Several treatment options have been described in the literature, but it remains unclear which treatment is most effective.

OBJECTIVE

The objective of this systematic review was to assess the effectiveness of any intervention in the treatment of MTSS.

STUDY SELECTION

Published or non-published studies, reporting randomized or non-randomized controlled trials of any treatment in subjects with MTSS were eligible for inclusion. Treatments were assessed for effects on pain, time to recovery or global perceived effect.

DATA SOURCES

Computerized bibliographic databases (MEDLINE, CENTRAL, EMBASE, CINAHL, PEDro and SPORTDiscus) and trial registries were searched for relevant reports, from their inception to 1 June 2012. Grey literature was searched for additional relevant reports.

STUDY APPRAISAL

The Cochrane Risk of Bias Tool was used to appraise study quality of randomized clinical trials (RCTs) whereas the Newcastle Ottawa Scale was used to appraise non-randomized trials. The 'levels of evidence', according to the Oxford Centre for Evidence-Based Medicine, addressed the impact of the assessed trials. Two reviewers independently performed the search for articles, study selection, data extraction and appraised methodological quality.

RESULTS

Eleven trials were included in this systematic review. All RCTs revealed a high risk of bias (Level 3 of evidence). Both non-randomized clinical trials were found to be of poor quality (Level 4 of evidence). RCTs, studying the effect of a lower leg brace versus no lower leg brace, and iontophoresis versus phonophoresis, were pooled using a fixed-effects model. No significant differences were found for lower leg braces (standardized mean difference [SMD] -0.06; 95 % CI -0.44 to 0.32, p = 0.76), or iontophoresis (SMD 0.09; 95 % CI -0.50 to 0.68, p = 0.76). Iontophoresis, phonophoresis, ice massage, ultrasound therapy, periosteal pecking and extracorporeal shockwave therapy (ESWT) could be effective in treating MTSS when compared with control (Level 3 to 4 of evidence). Low-energy laser treatment, stretching and strengthening exercises, sports compression stockings, lower leg braces and pulsed electromagnetic fields have not been proven to be effective in treating MTSS (level 3 of evidence).

CONCLUSION

None of the studies are sufficiently free from methodological bias to recommend any of the treatments investigated. Of those examined, ESWT appears to have the most promise.

The comprehensive description of stress fractures: a new classification system

BACKGROUND

Stress fractures represent a fatigue failure of bone, occurring with a spectrum of severity of structural injury, and healing potential varies by location. There is no comprehensive classification system for stress fractures incorporating both clinical and radiographic characteristics of the injury that is applicable to all bones. We introduce a system that is reproducible, generalizable, easy to use, and clinically relevant, with three descriptors: fracture grade, fracture location, and imaging modality.

METHODS

After a review of current classification systems, a five-tier system was proposed to determine fracture grade: Grade I indicated asymptomatic stress reaction on imaging, Grade II indicated pain with no fracture line, Grade III indicated non-displaced fracture, Grade IV indicated displaced fracture, and Grade V indicated nonunion. Example cases of each grade with clinical vignettes and images were prepared to test the interobserver and intraobserver reliability of the system by the test and retest evaluation among fifteen clinicians. A questionnaire and recall test assessed the ease of use, clinical applicability, and recall accuracy.

RESULTS

Test and retest analysis showed that the system had almost perfect agreement in intraobserver reliability with a kappa value of 0.81. The overall intraobserver reliability showed almost perfect agreement with a kappa value of 0.81. Almost perfect agreement with a kappa value of 0.83 was also produced when these responses were compared with our assessment. The overall interobserver reliability had substantial agreement with a kappa value of 0.78. The reliability of the group compared with that of the answer key was almost perfect with a kappa value of 0.83. The recall test showed an overall accuracy of 97.3%. Of the fifteen evaluators who completed questionnaires, fourteen (93.3%) said that the system would be easily remembered, would facilitate communication among colleagues, and would be useful in clinical practice.

CONCLUSIONS

The proposed stress fracture classification system is clinically relevant, easily applied, and generalizable, and has excellent interobserver and intraobserver reliability.

Bone stress injuries of the leg in athletes

Bone stress injuries, whose incidence is increasing among competitive and recreational athletes, represent a pathophysiological continuum along which a bone responds to a changing mechanical environment. Frank stress fracture is the endpoint of this process, resulting from the accumulation of microinjuries due to repeated abnormal stresses. The legs are largely the most frequently affected bone district. The aim of this paper is to review the imaging findings of the whole spectrum of stress-induced bone lesions of the leg in athletes. We emphasise the role of computed tomography and magnetic resonance imaging, which allow recognition of early alterations.

Validation of MRI classification system for tibial stress injuries

OBJECTIVE

The purpose of our study was to compare an MRI classification system for tibial stress injuries with semiquantitative MR features of injury severity and clinical outcome.

MATERIALS AND METHODS

Two musculoskeletal radiologists retrospectively reviewed in consensus the MR findings of 142 tibial stress injuries to quantify the degree of periosteal and bone marrow edema and grade the injuries using the Fredericson classification system (grade 1 = periosteal edema only, grade 2 = bone marrow edema visible on T2-weighted images, grade 3 = bone marrow edema visible on T1-weighted and T2-weighted images, grade 4a = multiple focal areas of intracortical signal abnormality, and grade 4b = linear areas of intracortical signal abnormality). Kruskal-Wallis tests were used to determine the relationship between the grade of stress injury and the degree of periosteal and bone marrow edema and the time to return to sports activity.

RESULTS

Grade 4b injuries had significantly (p < 0.002) more severe and grade 1 injuries less severe periosteal and bone marrow edema than grades 2, 3, and 4a injuries. Grade 4b injuries had significantly (p < 0.002) longer time and grade 1 injuries shorter time to return to sports activity than grades 2, 3, and 4a injuries. There was no significant difference (p = 0.06-0.79) among grades 2, 3, and 4a injuries in the degree of periosteal and bone marrow edema and the time to return to sports activity.

CONCLUSION

Grades 2, 3, and 4a stress injuries had similar degrees of periosteal and bone marrow edema and similar time to return to sports activity, which suggests that these three grades can be combined into a single category in an abbreviated Fredericson classification system.

Bisphosphonate-related femoral periosteal stress reactions: scoring system based on radiographic and MRI findings

OBJECTIVE

The purpose of this study was to review the radiographic and MRI findings of bisphosphonate-related femoral periosteal stress reactions to propose a scoring system for predicting symptoms and fracture risk.

MATERIALS AND METHODS

A retrospective study included patients undergoing long-term bisphosphonate therapy who had radiographic evidence of focal femoral periosteal thickening on radiographs and MR images. There were 43 femoral periosteal stress reactions in 33 patients; eight patients underwent MRI. Radiographs and MR images were evaluated for focal cortical thickening (periosteal and endosteal), bone edema, focal cortical abnormalities (radiolucency, striations, cavities), and dreaded black line. The radiographic score (derived with statistical methods) and simple scores (simple radiographic, MRI, and combined scores) were compared with symptoms and fracture outcome.

RESULTS

Logistic regression analysis showed an association between radiographic dreaded black line and symptoms (odds ratio, 68.0). Kaplan-Meier and Cox regression analyses showed radiographic dreaded black line (p < 0.0005; hazard ratio, 27.3) and focal cortical radiolucency (p = 0.011; hazard ratio, 6.8) were independent predictors of fracture. The survival score derived from Cox regression coefficients showed good separation of high- and low-risk groups. Mann-Whitney tests showed an association between MRI and combined scores and symptoms (p = 0.036, p = 0.036). The area under the receiver operating characteristic curve suggested better association with symptoms for MRI and combined scores than for simple radiographic scores (1.00, 1.00, 0.93).

CONCLUSION

In bisphosphonate-related femoral periosteal stress reactions, radiographic dreaded black line and MRI and combined scores were associated with symptoms, and radiographic survival score was predictive of fracture risk. The relation between MRI and combined scores and fracture was not statistically significant.

The additional value of a pneumatic leg brace in the treatment of recruits with medial tibial stress syndrome; a randomized study

OBJECTIVE

To study the additional effect of a pneumatic leg brace with standard rehabilitation for the treatment of medial tibial stress syndrome (MTSS) in recruits.

METHODS

In a single blinded randomized study, 15 recruits (age 17-22) followed a rehabilitation programme consisting of leg exercises and a graded running programme. Recruits performed daily exercises and ran three times a week. The running programme consisted of 6 consecutive phases. One group was, after randomization, additionally provided with a pneumatic leg brace. Follow-up was provided every other week. Days to completing the running programme was the primary outcome measure, the Sports Activity Rating Scale (SARS) score and satisfaction with the treatment were secondary outcome measures.

RESULTS

In total 14 recruits completed the rehabilitation programme. No differences were found in the number of days until phase six of the running schedule was finished between the brace and the control group (Brace 58.8 +/- 27.7 (mean +/- SD) vs Non-Brace 57.9 +/- 26.2 (mean +/- SD, p = 0.57). Also no differences were found in the SARS scores between the groups. Overall satisfaction with the treatment was 6.4 +/- 1.1 (mean +/- SD) on a 1-10 scale for the brace group and 7.1 +/- 0.7 (mean +/- SD) for the control group (p = 0.06). Comfort of the brace was assessed as 4.8 +/- 1.3 (mean +/- SD) on a 1-10 scale.

CONCLUSIONS

No additional large effect of the pneumatic leg brace could be found in recruits and wearing of the brace was not feasible, since the wearing comfort was low.

[Stress fractures]

In 1892, J. Wolff, an orthopedic surgeon, stated that the internal architecture and shape of a bone were related to the direction of stresses placed upon it. Conventional radiographs and MRI can demonstrate the adaptability of bones to stresses. Imaging also demonstrates that this adaptability has limitations, and that excessive stress may lead to fracture.

The classification systems of stress fractures: a systematic review

BACKGROUND

Stress fractures of the upper and lower extremity are troublesome overuse injuries in athletes and nonathletes alike. These injuries have a broad spectrum of severity and prognosis. We performed a systematic search of the literature, which revealed multiple classification systems; however, we did not uncover a general system that offered both validated radiographic and clinical parameters.

METHODS

A literature search was conducted using Ovid/Medline, Embase, and the Cochrane Library, with publication dates ranging from 1960 to December 2009. Inclusion criteria included all studies and review articles regarding stress or fatigue fractures and their classification.

RESULTS

Forty-three studies and/or articles were identified for this review. Of these articles, 27 classification systems were referenced. Sixteen of the systems were applicable to any injury location, and 1 applied to specific bones (femoral neck, tibia, tarsal navicular, pars interarticularis, and fifth metatarsal). Four classification systems were referenced more often than others. Of the classification systems, 11 were based on radiographs alone, while the other 16 used a variety of radiographic modalities, including radiographs, bone scans, computed tomography, ultrasound, and magnetic resonance imaging.

CONCLUSION

There are many different stress fracture classification systems in the literature. These systems employ various imaging modalities, but few include clinical parameters. Many are site specific. Of those that are widely applicable, no general classification system has been shown to be reproducible, easily accessible, safe, inexpensive, and clinically relevant. A gold standard classification system for describing stress fractures has yet to be determined.

Imaging of triathlon injuries

Injuries in triathletes are common and are mostly overuse injuries. Rotator cuff tendinitis is the most common complaint from swimming, but the incidence of tendinopathy and rotator cuff tears on magnetic resonance imaging is comparable in triathletes without and with shoulder pain. Cycling injuries are mainly to the knee, including patellar tendinosis, iliotibial band syndrome, and patellofemoral stress syndrome, and to the Achilles tendon and the cervical and lumbar spine. Running is associated with most injuries in triathletes, during both training and racing, causing the athlete to discontinue the triathlon. In addition to knee injuries from running, triathletes may also develop foot and ankle, lower leg, and hip injuries similar to single-sport distance runners. Some injuries in triathletes may be mainly symptomatic during one of the three sports but are exacerbated by one or both of the other disciplines.

Risk factors and prognostic indicators for medial tibial stress syndrome

The objective of the study was to examine the risk factors and prognostic indicators for medial tibial stress syndrome (MTSS). In total, 35 subjects were included in the study. For the risk factor analysis, the following parameters were investigated: hip internal and external ranges of motion, knee flexion and extension, dorsal and plantar ankle flexion, hallux flexion and extension, subtalar eversion and inversion, maximal calf girth, lean calf girth, standing foot angle and navicular drop test. After multivariate regression decreased hip internal range of motion, increased ankle plantar flexion and positive navicular drop were associated with MTSS. A higher body mass index was associated with a longer duration to full recovery. For other prognostic indicators, no relationship was found.

Low-energy extracorporeal shock wave therapy as a treatment for medial tibial stress syndrome

BACKGROUND

Medial tibial stress syndrome (MTSS) is a pain syndrome along the tibial origin of the tibialis posterior or soleus muscle. Extracorporeal shock wave therapy (SWT) is effective in numerous types of insertional pain syndromes.

HYPOTHESIS

Shock wave therapy is an effective treatment for chronic MTSS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Forty-seven consecutive subjects with chronic recalcitrant MTSS underwent a standardized home training program, and received repetitive low-energy radial SWT (2000 shocks; 2.5 bars of pressure, which is equal to 0.1 mJ/mm(2); total energy flux density, 200 mJ/mm(2); no local anesthesia) (treatment group). Forty-seven subjects with chronic recalcitrant MTSS were not treated with SWT, but underwent a standardized home training program only (control group). Evaluation was by change in numeric rating scale. Degree of recovery was measured on a 6-point Likert scale (subjects with a rating of completely recovered or much improved were rated as treatment success).

RESULTS

One month, 4 months, and 15 months from baseline, success rates for the control and treatment groups according to the Likert scale were 13% and 30% (P < .001), 30% and 64% (P < .001), and 37% and 76% (P < .001), respectively. One month, 4 months, and 15 months from baseline, the mean numeric rating scale for the control and treatment groups were 7.3 and 5.8 (P < .001), 6.9 and 3.8 (P < .001), and 5.3 and 2.7 (P < .001), respectively. At 15 months from baseline, 40 of the 47 subjects in the treatment group had been able to return to their preferred sport at their preinjury level, as had 22 of the 47 control subjects.

CONCLUSION

Radial SWT as applied was an effective treatment for MTSS.

Current developments concerning medial tibial stress syndrome

Medial tibial stress syndrome (MTSS) is one of the most common lower leg injuries in athletes who run. Studies have reported MTSS to occur in 4% to 20% of this population. It can be defined as an overuse injury that creates pain over an area covering the distal to middle third of the posteriomedial tibial border, which occurs during exercise and creates cyclic loading. Differential diagnosis includes ischemic disorders and stress fractures. Although the pathology of this injury is understood, the etiology is less agreed upon. This makes it difficult for clinicians to diagnose and treat this common injury. The purpose of this article is to present health care practitioners with the most current information regarding MTSS so they can better diagnose and treat this common injury. To this end, a literature review was conducted, with the most current results presented. The areas of etiological theories, imaging techniques, and treatment options for MTSS were searched. Five of the most prevalent etiological theories are presented with supporting evidence. Of the imaging tools available to the clinician, magnetic resonance imaging (MRI) and bone scintigraphy have comparable specificity and sensitivity. Clinicians should first make the clinical diagnosis of MTSS, however, because of high percentages of positive MRI scans in asymptomatic patients. There have been few randomized controlled trials investigating treatment options for athletes with MTSS. Those that have been performed rendered no significant findings, leading researchers to conclude that rest is equal to or better than other treatment options. Given the evidence, treatment suggestions for practitioners caring for athletes with MTSS are provided.

Medial tibial stress syndrome: a critical review

Medial tibial stress syndrome (MTSS) is one of the most common leg injuries in athletes and soldiers. The incidence of MTSS is reported as being between 4% and 35% in military personnel and athletes. The name given to this condition refers to pain on the posteromedial tibial border during exercise, with pain on palpation of the tibia over a length of at least 5 cm. Histological studies fail to provide evidence that MTSS is caused by periostitis as a result of traction. It is caused by bony resorption that outpaces bone formation of the tibial cortex. Evidence for this overloaded adaptation of the cortex is found in several studies describing MTSS findings on bone scan, magnetic resonance imaging (MRI), high-resolution computed tomography (CT) scan and dual energy x-ray absorptiometry. The diagnosis is made based on physical examination, although only one study has been conducted on this subject. Additional imaging such as bone, CT and MRI scans has been well studied but is of limited value. The prevalence of abnormal findings in asymptomatic subjects means that results should be interpreted with caution. Excessive pronation of the foot while standing and female sex were found to be intrinsic risk factors in multiple prospective studies. Other intrinsic risk factors found in single prospective studies are higher body mass index, greater internal and external ranges of hip motion, and calf girth. Previous history of MTSS was shown to be an extrinsic risk factor. The treatment of MTSS has been examined in three randomized controlled studies. In these studies rest is equal to any intervention. The use of neoprene or semi-rigid orthotics may help prevent MTSS, as evidenced by two large prospective studies.

Foot and ankle imaging in the athlete

Foot and ankle injuries are among the most common of all sports-related injuries. Many injuries are simplistic from a diagnostic standpoint, whereas others require a high level of suspicion and the use of appropriate diagnostic imaging modalities. Whether a professional athlete or a weekend warrior, all athletes want minimal disruption to their sporting activity and a quick return to competition. An accurate diagnosis aids in the development of an appropriate rehabilitation program and in return to activity. This article reviews the more common foot and ankle injuries seen in the podiatrist's office and the preferred imaging modalities used to evaluate them.