Clinical Practice Patterns of Isthmic Spondylolysis in Young Athletes: A Survey of Pediatric Research in Sports Medicine Members : Current Sports Medicine Reports

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Clinical Practice Patterns of Isthmic Spondylolysis in Young Athletes: A Survey of Pediatric Research in Sports Medicine Members

Hollabaugh, William L. MD1; Foley Davelaar, Cassidy M. MD2; McHorse, Kevin J. PT3; Achar, Suraj A. MD4; MacDonald, James P. MD, MPH5; Riederer, Mark F. MD6

Author Information
Current Sports Medicine Reports: November 2022 - Volume 21 - Issue 11 - p 405-412
doi: 10.1249/JSR.0000000000001008
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Abstract

Introduction

Low back pain (LBP) is common in pediatric and adolescent patients and has been reported in up to 50% of athletes (1,2). Unlike adults where back pain is typically due to a nonspecific etiology, the growing spine of the adolescent introduces unique variables in the assessment and management of lumbar injuries. There are several unique causes of pediatric and adolescent LBP that should be considered and identified when present, so treatment can be tailored appropriately (3). This is especially true for athletes. Isthmic spondylolysis is one such etiology that merits attention, as the identification and treatment of this etiology is nuanced. Moreover, it is a relatively common etiology of LBP, with a prevalence of 4.4% to 6.0% in all pediatric and adolescent patients (4,5).

The Wiltse Classification categorizes spondylolysis into five subtypes: isthmic, dysplastic, degenerative, traumatic, and pathologic (6). Isthmic spondylolysis is defined as a unilateral or bilateral bone stress injury secondary to repetitive, mechanical spinal loading during activity of the lumbar vertebra neural arch, classically the pars interarticularis (6,7). Isthmic spondylolysis is the most common subtype of spondylolysis in athletes accounting for up to 47% of presentations (2,7–12). Although found more frequently in certain “high risk” sports (e.g., gymnastics, football, baseball), isthmic spondylolysis has been described in participants of most sports and the diagnosis should be entertained when treating any adolescent athlete with lower back pain (13–18). Because lumbar hyperextension and axial rotation increase force transmitted through the posterior elements of the vertebrae, it is thought that athletes who perform these motions repeatedly have an increased risk of developing isthmic spondylolysis (19–22).

Presentation

Isthmic spondylolysis characteristically presents in adolescent athletes with insidious and gradual onset of LBP that may radiate to the buttocks and/or upper thighs (5,14). The LBP classically increases with activity and is relieved by rest (4). Isthmic spondylolysis is uncommonly associated with abnormal neurologic findings or neurologic symptoms, and when present, additional diagnoses should be contemplated (14,23). Similarly, constitutional symptoms, such as night sweats, fevers, and/or chills are not associated with isthmic spondylolysis and should lead to investigation for infectious, rheumatologic, and/or oncologic etiologies (24). The L5 pars interarticularis accounts for 85% to 95% of cases, followed by L4, which accounts for 5% to 15% of cases (9,10,13,14,25).

Physical Examination

Physical examination of a patient with isthmic spondylolysis typically displays reproducible LBP with lumbar extension, rotation, and side bending (22,26,27). Lumbar range of motion may be decreased. Tenderness to palpation is often present over the spinous process of the affected vertebra in addition to the surrounding paraspinous musculature (14). Characteristic examination findings include tight hamstrings and thoracolumbar musculature; a weak core, and gluteal musculature; increased or decreased lumbar lordosis; and an anteriorly rotated pelvis (4,22,23,28). The single leg extension test, or stork test, is commonly used in the diagnosis of isthmic spondylolysis (23,27). Although the single-leg extension test may reproduce ipsilateral or bilateral LBP in patients with isthmic spondylolysis, recent studies have reported limited diagnostic benefit (29). Particularly, a recent study suggested the sensitivity and specificity of the single leg extension test in the diagnosis of isthmic spondylolysis to be as low as 40% to 50% (29). In addition, no association between a positive or negative single leg extension test and the presence or absence of isthmic spondylolysis was found (29).

Imaging

Imaging recommendations for the diagnosis of spondylolysis have changed over the years as technology has advanced. Plain radiographs remain the first line of imaging. The most valuable radiograph projections include the coned lateral view of the lumbosacral junction, which is most likely to detect an abnormality if present, and the anteroposterior (AP) view with 30 degrees of cranial angulation (30). A lateral oblique projection also may be obtained. The benefit of obtaining a lateral oblique projection has been found to be quite low, displaying no difference in sensitivity between two projections (AP, lateral) versus four projections (AP, lateral, right oblique, left oblique) while also exposing the patient to nearly twice the radiation dose (31,32). For example, a pediatric technique (70 to 75 kVp) oblique radiograph image exposes the gonads of a 10-year-old girl to 270 mrad compared with 52 mrad for a lateral projection and 214 mrad for an AP projection (33). Yet, radiographs are limited in their detection of isthmic spondylolysis and have a false-negative rate of up to 52% when compared with magnetic resonance imaging (MRI) (34). Furthermore, the sensitivity of AP and lateral projections alone is 75% when compared with nuclear medicine bone scintigraphy (bone scans) and computed tomography (CT), 84% and 90%, respectively (31). While bone scans were historically often obtained, they expose the patient to seven to nine times the effective dose of two-view plain radiographs and identify less cases of isthmic spondylolysis when compared with CT and MRI (31,32). In the case of young athletes, bone scans and lateral oblique projections have limited value, especially when radiation exposure is considered (4,31,32,35).

MRI has benefits that radiographs cannot offer and may be the preferred advanced imaging modality of choice in isthmic spondylolysis not identified on radiographs. Advantages of MRI include its favorable side effect profile, its ability to identify early bone stress injury, its high positive predictive value, and its lack of radiation exposure (5,35,36). MRI also can detect abnormalities at additional levels of the lumbar spine that may not be identified on CT (32). However, the clinician must be aware of limitations of MRI in the diagnosis of isthmic spondylolysis. A high-quality MRI may be difficult to obtain in the young athlete population due to the potential for motion artifact. In addition, multiple studies have reported varying sensitivity and specificity of MRI in diagnosis isthmic spondylolysis (35–37). Recently, the sensitivity of MRI in diagnosing isthmic spondylolysis in a young population (mean age, 14.7 ± 1.5 years) was 59.1% compared with 77.3% for CT with a false-negative rate of 40.9% for MRI compared with 22.7% for CT (35). However, the development of innovative software tools when using MRI, such as ultrashort time to echo (UTE), has increased the sensitivity of detecting isthmic spondylolysis such that there may be diagnostic equivalency with CT while sparing the patient exposure to radiation (38).

While MRI has been reported to be less accurate compared with CT in diagnosing isthmic spondylolysis in young athletes, MRI can identify bony edematous changes that may be suggestive of an early isthmic spondylolysis (35,36). Specifically, hypointense signal on MRI in the pars interarticularis region may represent development of isthmic spondylolysis before the changes are visible on radiographs or CT (36). Moreover, MRI has a high positive predictive value (97%) for isthmic spondylolysis when bony edema is noted across the pars interarticularis (36). Determining the temporal nature of the defect (i.e., acute vs chronic) provides clinicians with a more accurate prediction of healing potential and a directed treatment plan. Therefore, MRI also may identify isthmic spondylolysis earlier than radiographs or CT (36). Lastly, MRI also has the added advantage that it better visualizes soft tissue structures than radiographs or CT and can detect potential concurrent pathology including degenerative disc disease, foraminal stenosis, disc herniation, and/or nerve root compression (36).

CT may offer advantages over radiographs and MRI. CT scans are quicker to perform than MRI, which decreases both the risk of anxiety associated with the imaging process and the potential for motion artifact. Although CT implicates radiation exposure, there are radiologic techniques (i.e., z-axis coverage protocol) that minimize radiation exposure to an amount similar to radiographs (39). Thus, CT with low-radiation protocols may even be considered as the initial imaging modality (39). However, CT is usually not used as the initial diagnostic test since it also tends to be substantially more expensive than radiographs. Although MRI better demonstrates soft tissue structures, CT displays more precise cortical bone images allowing for improved evaluation of incomplete versus complete fractures and bony healing (40). Specifically, if a pars defect on CT is wide with sclerotic margins, the lesion is more likely to be chronic and less likely to heal with conservative treatment. If a lesion is narrow with noncorticated margins, the lesion is more likely to be acute and more likely to heal with immobilization (40). Therefore, although MRI may benefit the clinician by initially establishing pathology and the acuity of the injury, studies suggest CT as the best imaging modality to assess the healing process and for longitudinal follow-up (32). In cases of acute onset of back pain in an athlete who performs repetitive back extension (e.g., gymnasts, dancers, figure skaters, or divers) a protocolized CT may be the ideal advanced imaging modality choice. In a less obvious scenario, MRI may be preferred due to its ability to detect early bony edematous changes, associated pathology, and offer less radiation exposure. Overall, a thorough understanding of the risks and benefits of radiographs, CT, and MRI will help both the clinician and the patient in the diagnosis and treatment of isthmic spondylolysis.

Treatments

Conservative treatment of isthmic spondylolysis is nonoperative and includes rest from pain provoking activities, activity restriction, PT, vitamin D supplementation, transcutaneous bone stimulator, low-intensity pulsed ultrasound, and antilordotic rigid or nonrigid bracing (4,19,22,25,41–45). The lack of consensus treatment guidelines and large-scale controlled clinical trials evaluating treatment options for isthmic spondylolysis produces difficulty in defining an optimal treatment algorithm (46). The goals of conservative treatment options are to promote healing, diminish pain, and prevent progression of the severity of the condition. Initial activity restriction, or temporary cessation of provoking activities, has historically been part of the conservative treatment for isthmic spondylolysis after diagnosis (5,27). Previously, activity restriction has been prescribed for a wide range of 2 to 6 months prior to beginning the return to sport process (14,47).

Physical Therapy

PT is well-described as a treatment for isthmic spondylolysis (43). Isthmic spondylolysis may result in lumbar instability leading to excess truncal translational and rotational instability (48). Typical PT regimens target muscle imbalances of the transversus abdominus and multifidus to promote improved segmental lumbar flexibility and stability (8,13,14,48–50). The course of PT normally lasts 2 to 4 months (14). Some experts recommend delaying the introduction of PT until after resolution of back pain or after three months of rest to permit healing of the bone stress injury and prevent progression of the severity of condition (47,51). This strategy of delayed introduction of PT has been reported to delay return to sport up to 7 months and also may increase the risks associated with prolonged rest, particularly weight gain, generalized muscle atrophy and anxiety associated with return to sport (8,52).

Although the aim of recommending initial rest is to achieve bony healing, studies have displayed that bony healing is not associated with improved clinical outcomes including the ability to return to sport and quality of life (5,51,53). More recently, both immediate and early introduction of PT has allowed patients to return to sport up to 2 months faster without increased risk of adverse events (8,50). Although early introduction of PT may decrease time to return to sport without increased risk of adverse events, higher level studies are needed to better clarify this recommendation.

Bracing

Antilordotic orthotic treatment with a rigid or nonrigid brace is a controversial topic but is often utilized in combination with conservative treatments. Duration of brace use is variable and has been recommended for 1 to 16 months (19,22,41,54). In a landmark study, use of a rigid thoracic lumbar sacral orthosis, known as the Boston Overlap Brace (BOB), in addition to PT resulted in successful return to sport in 80% of adolescents with isthmic spondylolysis (41). It was later reported that through a combination of the BOB and PT, 80% of patients were able to return to sport starting at 4 to 6 wk after initial diagnosis, if they continued to wear their brace and remained pain-free (22). Moreover, improved fracture union rates up to 94% for early bony defects at as early as 3.2 months after diagnosis have been reported while using the BOB (19). Although likely similar in result to nonbracing management of progressive bony defects, achievement of bony healing for progressive lesions with use of a BOB was less successful and time to return to sport was longer (19). Union rates and return to sport for progressive defects with high signal intensity and progressive defects with low signal intensity were 64% and 27%, and 5.4 and 5.7 months, respectively (19). It also has been proposed to use bracing until LBP resolves, ranging from 1 to 16 months (47). Results from the study revealed that 87% of the patients were able to fully return to sports (47).

Instead, a recent meta-analysis revealed that 84% of athletes with isthmic spondylolysis who were treated nonoperatively without nonrigid or rigid bracing returned to sports at 1 year with occasional or no pain with vigorous activities (5). The pooled and weighted rate of successful return at 1 year was 86% of the patients treated without a brace and 89% of patients treated with a brace (P = 0.75) (5). Therefore, the authors concluded that bracing does not affect clinical outcome. It also has been suggested that the benefit from bracing is instead due to activity restriction and not from the brace itself (54). Additional studies revealed that a combination of restriction of sport, activity modification, and physical therapy may lead to similar outcomes as brace wear (54). However, in the cases of elite athletes, noncompliance with activity restrictions, early defects, bilateral defects or athletes who need to return in a timely manner, bracing may be preferred and may allow a quicker return to sport (54).

Return to Sport

Young athletes with isthmic spondylolysis return to sport at their prior level of activity in 67% to 96% of cases with conservative management (5,8,13,47,51,55). A recent meta-analysis of 430 patients with isthmic spondylolysis determined that mean return to sport was 4.3 months (range: 2.0 to 5.2 months) (13). Although there is no consensus for RTP criteria for young athletes with isthmic spondylolysis, existing return to sport criteria are image-based, time-based, or symptom-based (13).

Because demonstration of bony healing of this condition is not associated with successful return to sport, it is not routinely advocated to use solely image-based criteria when deciding an athlete’s return to sport timeline (5,51,53). Time-based return to sport criteria varies widely, with recommendations for rest ranging from 2 to 6 months (14,47). Strict time-based return to sport criteria is rarely used in isolation in the treatment of isthmic spondylolysis. Symptom-based return to sport criteria necessitates that the athlete be pain free on physical examination and with all activity prior to return to sport (13,47). A combination of both time-based and symptom-based return to sport criteria are often used: after a defined period of rest and realization of pain free at rest and with activity, return to sport progression begins albeit with immediate cessation of offending activities if pain returns (14,49,56).

Return to sport may be decided on an individual basis, considering the patient and the type and level or sport (14). It is believed that some providers recommend a stepwise progression for return to sport and/or impose activity restrictions with return to sport, although the duration and nature of activity progression and features of activity restrictions with return to sport are not well-defined in the literature. Furthermore, reported outcome measures for treatment of isthmic spondylolysis include successful return to sport, visual analog pain scores, a Scoliosis Research Society questionnaire, and the Micheli Functional Scale (49,57,58).

Study Aim

The Pediatric Research in Sports Medicine (PRiSM) society is a multidisciplinary group of health care providers who provide clinical care to young athletes with a variety of conditions, including isthmic spondylolysis. PRiSM membership is divided into multidisciplinary research interest groups (RIG) who meet quarterly with the aim of advancing high-quality pediatric sports medicine research in certain areas of knowledge. Specifically, the Spine and Spondylolysis RIG aims to advance high-quality research on the epidemiology, diagnosis, imaging, and management of pediatric isthmic spondylolysis, and were the creators of this survey and publication. Although isthmic spondylolysis is a common diagnosis in adolescent athletes with considerable peer-reviewed, evidence-based research, there are significant clinical practice pattern differences between providers when they assess and manage LBP in adolescent athletes. The purpose of this study is twofold: to review the literature of diagnosis and management of the young athlete with isthmic spondylolysis and to survey Pediatric Research in Sports Medicine members during the 2021 annual meeting on practice patterns of diagnosis and management of the young athlete with isthmic spondylolysis.

Methods

An electronic, 29-question REDCap survey was created by members of the PRiSM Spine and Spondylolysis RIG and distributed electronically to the PRISM membership via email during the 2021 virtual annual meeting. Prior to distribution, the survey was approved by the PRiSM Research Committee. One reminder was sent after the meeting. Responses were collected over a 6-week period. The survey gathered information including demographics, diagnosis, imaging, and management of adolescents with isthmic spondylolysis.

Results

Demographics

Ninety-eight responses (27.0% survey response rate) were collected out of 366 total PRiSM members (Table 1). Using membership data, around 32.0% of PRiSM members who received this survey do not provide care for adolescents with lumbar spine disease. When accounting for survey recipients who do not provide care for adolescents with lumbar spine disease, the adjusted survey response rate was approximately 40.0%. Most respondents were orthopedic surgeons (37.5%) or nonsurgical sports medicine physicians (34.4%), and approximately half were sports medicine fellowship trained. Physical therapists made up the third most common group (22.9%). Other respondents included nonsurgical sports medicine mid-level providers, certified athletic trainers (ATC), and researchers. Nearly all respondents were pediatric-trained or pediatric-focused in their area of training. Most respondents trained in the Northeast (39.6%), with an even distribution of providers trained in the Southeast (20.8%), Midwest (18.8%), and West (18.8%). The mean number of hours providers see patients in clinic is 37.5 hours/week with most seeing between 0 and 10 young athletes with isthmic spondylolysis in clinic per year. Providers in the survey primarily practice in the Northeast (28.4%), West (24.2%), and Midwest (23.2%).

Table 1 - Characteristics of the study population.
Total Population No. Respondents Percent
Respondents 98 27.0
Specialty 96
 Orthopedic surgeons 36 37.5
 Nonsurgical sports medicine  physicians 33 34.4
 Physical therapists 22 22.9
 Nonsurgical sports medicine  mid-level providers 3 3.1
 Certified athletic trainers 1 1.0
 Researchers 1 1.0
Sports medicine fellowship-trained 96
 Yes 49 51.0
Pediatric-focused medical practice 38
 Yes 33 86.8
Geographic area of medical training 48
 Northeast 19 39.6
 Southeast 10 20.8
 Midwest 9 18.8
 West 9 18.8
Geographic location of clinical practice 95
 Northeast 27 28.4
 West 23 24.2
 Midwest 22 23.2
 Southwest 12 12.6
 Southeast 11 11.6
Median number of hours of direct  patient care (median hours/week) 96 37.5
No. patients with isthmic spondylolysis seen/year 97
 0 to 10 49 50.5
 10 to 30 34 35.1
 >30 7 7.2
 0 7 7.2

Diagnosis

All respondents use history and examination as the primary method of making the diagnosis of isthmic spondylolysis, with the majority (84.6%) utilizing plain radiographs at the initial visit (Table 2). Approximately 42% of respondents use MRI as an imaging aid in making the initial diagnosis. Pain with extension and pain with single leg hyperextension testing are the primary physical examination tests used by providers that are suggestive for the diagnosis of isthmic spondylolysis (94.5% and 75.8%, respectively). Midline lumbar spinous process tenderness and pain with single leg hop testing were considered less reliable in making the diagnosis by physical examination (48.4% and 27.5%, respectively).

Table 2 - Characteristics of survey respondents regarding diagnosis of isthmic spondylolysis.
Diagnosis of Isthmic Spondylolysis No. Respondents Percent
Modalities used at initial patient presentation 91
 History 91 100.0
 Physical Examination 91 100.0
 Plain radiographs 77 84.6
 MRI 38 41.8
 CT 12 13.2
 SPECT/CT 6 6.6
 Bone scan 2 2.2
Physical examination maneuvers suggestive of isthmic spondylolysis 91
 Pain with lumbar extension 86 94.5
 Single leg hyperextension test 69 75.8
 Midline lumbar spinous process  tenderness 44 48.4
 Pain with single leg hop test 25 27.5
Use of oblique projection with radiographs 68
 Yes 16 23.5
Use of standing radiographs 68
 Yes 48 70.6
Use of L5/S1 “spot view” with radiographs 68
 Yes 23 33.8
Initial advanced imaging modality 67
 MRI 60 89.6
 SPECT/CT 4 6.0
 CT 3 4.5
 Bone scan 0 0.0
Use of repeat imaging to verify healing 67
 Yes 3 4.5

Imaging

Plain radiographs are regularly (84.6%) used as the first line imaging modality in the diagnosis of isthmic spondylolysis. While only 23.5% of providers use oblique images, the majority (76.5%) use only anteroposterior and lateral plain radiographs images (Table 2). Additionally, most providers do not insist on plain radiographs being standing (70.6%) or using an L5/S1 spot view (66.2%). MRI has become the most popular advanced imaging diagnostic study, with almost 90% of those surveyed utilizing this compared to CT, single photon emission computed tomography/computed tomography (SPECT/CT), or bone scan. Essentially all respondents do not routinely order imaging to verify healing (95.5%).

Management

The use of rigid bracing varies widely amongst respondents. Approximately half (44.1%) of respondents do not use rigid TLSO bracing. The remaining respondents use rigid TLSO bracing in some capacity, with 35.3% using it sometimes and 20.6% using it consistently (Table 3). Of those who use rigid TLSO bracing, the mean duration of use is approximately 8 wk (range, 2–13 wk). Nonrigid bracing is used slightly more frequently, with 17.6% of respondents using it consistently, 44.1% using it sometimes, and 38.2% not using it at all. When nonrigid bracing is prescribed, the mean duration of use is approximately 6 weeks (range, 4 to 10 wk). Electromagnetic bone stimulation is not commonly prescribed by respondents, with only 9.0% sometimes using it. Similarly, ultrasound bone stimulation is not commonly used by respondents, with only 10.0% sometimes using this.

Table 3 - Characteristics of survey respondents regarding management of isthmic spondylolysis.
Management of Isthmic Spondylolysis No. Respondents Percent
Use of rigid bracing 68
 No 30 44.1
 Sometimes 24 35.3
 Always 14 20.6
Duration of rigid bracing, mean (range) 12
 8 wk +/− 2 to 13 wk
Use of nonrigid bracing 68
 Sometimes 30 44.1
 No 26 38.2
 Always 12 17.6
Duration of rigid bracing, mean (range) 10
 6 wk +/− 4 to 10 wk
Use of electromagnetic bone stimulation (ex. Exogen) 67
 No 61 91
 Sometimes 6 9.0
Use of ultrasound bone stimulation 68
 No 61 89.7
 Sometimes 7 10.3
 Yes 23 33.8
Use of physical therapy 68
 Yes 68 100.0
Recommendation of rest prior to beginning physical therapy 68
 Yes 39 57.4
Prescription of activity restrictions with return to sport 68
 Yes 36 52.9
Return to sport criteria 68
 Able to perform sport-specific  activities without pain 64 94.1
 No pain with lumbar extension 59 86.6
 Has completed physical therapy 45 66.2
 Rates feeling >90% back to baseline 41 60.3
 Has a minimum amount of time  off from sport 21 30.9
 Other 6 8.8
 Has radiographic healing on  radiographs or CT 4 5.9

PT was used by all respondents (100.0%) for isthmic spondylolysis. However, there is variance with regards to timing of initiation of PT by providers, with 42.6% prescribing it immediately after diagnosis versus 57.4% prescribing a period of rest prior to beginning PT (Table 3). Also, providers are split on recommending activity restrictions when athletes return to sport, with 52.9% indicating that they recommend some type of restriction versus 47.1% not recommending any restrictions. Providers who answered the PRiSM survey seemed to have similar return to sport criteria: 94.1% of providers required no pain with their sport before return to sport competitively and 86.6% required no pain with lumbar extension. Most providers required that the athlete to be back to baseline (60.3%) or have completed PT (66.2%).

Discussion

Isthmic spondylolysis is a common problem in the young athlete, and sports medicine physicians, physical therapists, radiologists, and others should be thoroughly familiar with the nuances of diagnosis and management if they care for athletes in this age group. Our study is both a review of the current literature on the diagnosis and management of this condition and a report on the results of a survey taken by the primary group (PRiSM members) of clinicians who diagnose and manage this condition regularly. The results of the PRiSM survey demonstrate a lack of consensus, most notably in management, which currently exists amongst providers with considerable experience caring for this population of patients.

Survey respondents generally agreed that pain with lumbar extension (94.5%) and the single leg extension test (75.8%) were helpful physical examination maneuvers contributing to the diagnosis of isthmic spondylolysis. Less providers required midline lumbar spinous process tenderness (48.4%) or pain with single leg hop testing (27.5%) to suggest the diagnosis. As our survey suggests, four view radiographs that include oblique views (23.5%) have fallen out of favor likely due to a combination of poor sensitivity and increased radiation exposure. Although CT and SPECT/CT are excellent modalities to diagnose isthmic spondylolysis, our survey results indicate that MRI has become the most popular advanced imaging modality (89.6%) to confirm isthmic spondylolysis. Driving this transition to the use of MRI are likely its improvements in sensitivity, its ability to identify early bone stress injury, its favorable side effect profile including lack of radiation exposure and its ability to detect concurrent pathology.

Management of isthmic spondylolysis remains an area of scientific evolution and limited practice-based research. It also is the area where there is the greatest variability demonstrated among clinicians, both in our review of the literature and in our survey. A recent meta-analysis of imaging modalities used in diagnosing isthmic spondylolysis demonstrated that while only a small percent of bilateral injuries heal (18%), a larger fraction of unilateral injuries (71%) eventually heal (5). Since fracture healing is not universal, treatment is generally focused on both pain relief and return to sport rather than radiographic healing. Most of our survey respondents (95%) concur with lack of need for repeat imaging in adolescent athletes who are doing well, avoiding potentially unnecessary radiation exposure.

Recommendations for activity modification are based on low level evidence and providers from PRiSM are rather evenly divided on restriction from sport. Research on bracing is similarly limited to retrospective studies that do not demonstrate improvement in clinical outcomes including return to sport or symptom recurrence (5,55). PRiSM survey results reflected the respondents’ mixed view of the limited evidence regarding bracing, as only a minority of the respondents consistently use rigid (20.6%) or nonrigid (17.6%) bracing.

Physical therapy is a cornerstone of management of many pediatric sports medicine conditions. Isthmic spondylolysis is no exception, and all PRISM respondents refer patients with isthmic spondylolysis to PT (100%). The demonstrated variance in survey responses regarding the use of PT relates to the timing of the referral, with a slight majority (57.4%) recommending a period of rest prior to starting PT. Although evidenced-based research on the timing of PT in adolescents with isthmic spondylolysis is limited, early PT may improve education, reduce anxiety, and both reduce fear of activity and fear of re-injury (3,8,43,47,50–52,55). Principally, physical therapists focus on promoting segmental lumbar stability, flexibility, and abdominal and spine strength rather than just general exercise (8,13,14,48–50,57). Additionally, physical therapists typically spend more time with athletes than clinicians and can discuss feelings of loss and frustration while they are starting to access and treat athletes. Finally, working with the physical therapist can give the athlete an empowering feeling of agency while they are initially out of their sport.

Although our PRiSM study is limited by the total number of respondents, we had a heterogenous group of pediatric orthopedic surgeons, primary care pediatric sports medicine specialists, PTs, and ATCs complete the survey, resulting in a unique clinical practice survey incorporating multiple providers and treatment specialists of isthmic spondylolysis. Respondents’ most cited reason for not completing the survey was their lack of participation in caring for adolescents with lumbar spine disease. In some academic medical centers, only a limited portion of surgeons and primary care providers care for most adolescents with back pain. Furthermore, at many academic medical centers, clinicians with a specialty in sports medicine, foot and ankle injuries, hand injuries, and developmental conditions do not allow for routine scheduling of adolescents with back pain.

The lack of consensus on the tools for diagnosis and management of isthmic spondylolysis suggests the need for large prospective randomized controlled clinical trials to investigate best practices for addressing this common condition. We think this is especially critical in the area of management, given the greater variability in this area that we demonstrated in our literature review and practice survey. There is a critical need to go beyond expert opinion and rely on evidence-based medical principles when recommending types and timing of physical therapy, the use (or not) of bracing, and the timing on return to sport.

Conclusion

Although there are similarities in how the diagnosis of isthmic spondylolysis in young athletes is made by PRISM members, there is variability in management, especially the use of bracing, the timing of physical therapy, and return to sport restrictions. MRI is the most common advanced imaging modality being used to help with the diagnosis.

Author Disclosure: This special communication does not contain a discussion of an unapproved or investigative use of a commercial product/device. The authors declare no conflict of interest and do not have any financial disclosures or financial funding relevant to this manuscript.

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