Avulsion fractures of the anterior inferior iliac spine: the case for surgical intervention

Apophyseal ilium avulsion fractures in young athletes: a systematic review and return to sport analysis

The purpose of the current investigation was to synthesize the epidemiology, cause, management, and return to sport (RTS) outcomes of ilium avulsion fractures sustained during sporting activities in young athletes. Studies reporting on athletes <18 years old sustaining an avulsion fracture along the ilium [injury to the anterior superior or inferior iliac spine (ASIS or AIIS), or the iliac crest (IC)], and the athlete's RTS status were included. RTS was analyzed by injury acuity, location, mechanism of injury, and management, whereas complications were recorded. Seventy studies comprising 286 avulsions (169 ASIS, 87 AIIS, and 30 IC) were included. The mean age of athletes was 14.5 + 1.3 years (range, 8-18 years). Sprinting (n = 103/286; 36.0%) and soccer (n = 97/286; 33.9%) were the most common sports during which injuries occurred. A total of 96.5% (n = 276/286) of athletes reported successful RTS at an average of 16.2 + 19.3 weeks. The RTS rate for patients sustaining ASIS, AIIS, and IC avulsions was 95.3, 97.7, and 100%, respectively. Acute trauma was responsible for 89.8% (n = 158/176) of injuries, which demonstrated a significantly faster (13.3 + 9.3 weeks) and higher RTS rate (99.4%) compared with those with chronic avulsions (74.4 + 40.9 weeks and 83.3%, respectively). Those with complications (18.2%) had a significantly lower RTS rate (90.4%) and longer recovery (23.7 weeks) compared with athletes without complications (97.9% and 14.5 weeks, respectively). Outcomes were not significantly different based on sex or management. However, chronic avulsions and postoperative complications sustained worse RTS results. An accurate and timely diagnosis is crucial when presented with these rare injuries to avoid increasing the chronicity of injury.

Reevaluation of the surgical indications for anterior inferior iliac spine avulsion fractures in an acute setting - A narrative review of the current literature

Purpose

The anterior inferior iliac spine (AIIS) is a frequent site of avulsion fracture in the pelvis, and these lesions could be observed mainly in teenage athletes. The present study aimed to re-evaluate the appropriate acute surgical treatment of AIIS avulsion fractures considering the three-dimensional anatomy of the supracetabular region.

Methods

This study evaluated current evidence of AIIS avulsion fracture treatments and outcomes. A literature search was done in the following databases: PubMed, SCOPUS, Embase, and Cochrane Library. All relevant information was used in this review.

Results

Several studies have shown how conservative treatment of these injuries lead to excellent outcomes, even when there is radiological evidence of displacement. However, only some surgeons describe clinical and radiological follow-up beyond six months. On the other side, recent studies have demonstrated the efficacy of arthroscopic or open procedures to solve a frequent cause of extra-articular femur-acetabular impingement (FAI) syndrome associated with previous AIIS avulsion fractures, the so-called sub-spine impingement. The acute surgical indication in AIIS avulsion fractures should be considered according to the three-dimensional anatomy of the supracetabular region, especially in young patients with high functional demands.

Conclusions

Three-dimensional assessment allows accurate evaluation of the position and dislocation of the fragment, predicting the risk of complications related to conservative treatment and guiding toward surgical indication only when appropriate.

Should proximal ruptures of the anterior rectus femoris muscle be treated surgically?

PURPOSE

No therapeutic consensus has been established about proximal ruptures of the rectus femoris muscle. The objective of this literature review is to determine a therapeutic course of action.

METHODS

We conducted a literature review on the PubMed database using the following keywords (in French and English, respectively): "quadriceps/quadriceps", "droit antérieur/rectus femoris", "proximal/proximal", "chirurgie/surgical", "avulsion/avulsion". We collected 266 articles, 36 of them were selected, which were related to our topic: proximal rupture of the anterior rectus femoris. Patients with a proximal rupture of the rectus femoris, minor or major patient of traumatic origin were included in this study. Patients injured at another lesion level, or non-traumatic lesions of the proximal rectus femoris (tendinitis without ruptures, tumor or others) were excluded. For each patient, the indications, the type of treatment and the functional result were analyzed, with the time to recovery and the level of recovery from sports and professional activities (same sport/profession or not, same level or not) as the main criterion of judgment. Fisher exact test was used for statistical comparison.

RESULTS

The aims of conservative treatment are to be pain free for the patient, to fight hematoma and to rehabilitate the injury as quickly as possible. The surgical techniques are varied, with most consisting of either a reinsertion of the musculo-tendon stump or a resection of the scar tissue with myo-tendino-aponeurotic suture in place. The functional results are good for the majority of the treatments proposed, but the conservative treatment has a shorter recovery time (3 months vs. 4 months for the best surgical results). Highly displaced bone avulsion is the only indication for first-line surgical treatment.

CONSLUSION

The main disadvantage of conservative treatment is the risk of residual pain beyond 3 months (10%), justifying an MRI to guide secondary surgical treatment. We propose a treatment plan for proximal rupture of the proximal rectus femoris rupture.

Avulsion injuries: an update on radiologic findings

Avulsion injuries result from the application of a tensile force to a musculoskeletal unit or ligament. Although injuries tend to occur more commonly in skeletally immature populations due to the weakness of their apophysis, adults may also be subject to avulsion fractures, particularly those with osteoporotic bones. The most common sites of avulsion injuries in adolescents and children are apophyses of the pelvis and knee. In adults, avulsion injuries commonly occur within the tendon due to underlying degeneration or tendinosis. However, any location can be involved in avulsion injuries. Radiography is the first imaging modality to diagnose avulsion injury, although advanced imaging modalities are occasionally required to identify subtle lesions or to fully delineate the extent of the injury. Ultrasonography has a high spatial resolution with a dynamic assessment potential and allows the comparison of a bone avulsion with the opposite side. Computed tomography is more sensitive for depicting a tiny osseous fragment located adjacent to the expected attachment site of a ligament, tendon, or capsule. Moreover, magnetic resonance imaging is the best imaging modality for the evaluation of soft tissue abnormalities, especially the affected muscles, tendons, and ligaments. Acute avulsion injuries usually manifest as avulsed bone fragments. In contrast, chronic injuries can easily mimic other disease processes, such as infections or neoplasms. Therefore, recognizing the vulnerable sites and characteristic imaging features of avulsion fractures would be helpful in ensuring accurate diagnosis and appropriate patient management. To this end, familiarity with musculoskeletal anatomy and mechanism of injury is necessary.

Avulsion Injuries and Ruptures of the Proximal Rectus Femoris in Skeletally Mature, High-Level Athletes: A Critical Analysis Review

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Injuries to the proximal rectus femoris remain rare, occurring primarily in soccer and American football athletes during kicking and sprinting because of its unique biarthrodial nature.

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The appropriate diagnosis is dependent on careful physical examination and imaging interpretation.

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While no universal treatment algorithm has been adopted for high-level athletes, recent investigations support operative repair using suture anchors to restore strength and function in order to allow an effective return to competition while minimizing the risk of injury recurrence.

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Complications following surgical management include injury to the lateral femoral cutaneous nerve and hematoma formation, and there are reports of residual pain and weakness with chronic injuries that fail the initial nonoperative treatment.

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Current investigations examining outcomes following treatment remain limited, warranting additional studies that examine patient-reported results, return-to-play rates, and the role of orthobiologics and accelerated rehabilitation protocols following injury to further improve athlete health and safety.

[Proximal avulsion of the rectus femoris muscle]

BACKGROUND

Injuries of the thigh muscles are among the most frequent sports injuries. For example, in soccer they represent nearly 30% of all injuries. The rectus femoris muscle is particularly exposed to injury due to its anatomical features. While distal ruptures involve the quadriceps tendon and are among the more frequent injuries not only in sports, proximal ruptures represent a rarity. Because of the mostly indifferent clinical signs, the diagnosis is often delayed. In the literature various versions of classifications on the grading of muscle injuries have been described.

OBJECTIVE

With respect to the rectus femoris muscle, there is no classification system from which a treatment decision or an algorithm can be derived. The problem is not only the unclear classification of the injury but also the variability of treatment options resulting from this.

MATERIAL AND METHODS

A selective search of the literature was carried out to construct a review article.

RESULTS

No standardized follow-up treatment after surgical interventions or an established procedure for conservative treatment is currently available.

CONCLUSION

The comparison of the individual studies is made difficult due to the low case numbers and nonuniform classification systems. A valid treatment algorithm can only be derived with difficulty based on the currently available data.

Conservative Treatment of Avulsion Injuries of the Lesser Trochanter in Adolescent Athletes

BACKGROUND

 Avulsion injuries of the lesser trochanter apophysis are relatively uncommon injuries and there have been no peer-reviewed case series dedicated to the evaluation and treatment of this injury. The purpose of this study is to characterize avulsion injuries of the lesser trochanter apophysis, review treatment protocols, and time to return to sport.  Methods: We reviewed 30 confirmed avulsion fractures of the lesser trochanter. Clinical data were reviewed to evaluate treatment protocols, duration, and time to return to sport. Radiographs were reviewed to confirm lesser trochanter avulsion and fracture displacement.

RESULTS

There were 26 males and 4 females, with the average age at the time of injury being 14.2 years. Treatment modalities consisted of protective weight-bearing, discontinuation of the patient's sport in all cases, and formal physical therapy in 18 cases. The average treatment duration was 30.7 days. The mean follow-up time was 102 days. The radiographic assessment demonstrated an average fracture displacement of 5.1 mm. The average return to sport was 11 weeks.

CONCLUSION

This is the first large case series studying avulsion injuries of the lesser trochanter. We have shown that these athletes can be managed non-surgically and can successfully return back to sport within three months.

Prevalence of Anterior Inferior Iliac Spine Dysmorphism and Development of a Novel Classification System: An Anatomic Study of 1,797 Cadaveric Specimens

Purpose: Subspine impingement occurs due to a morphologically abnormal anterior inferior iliac spine (AIIS), capable of causing impingement against the distal femoral neck. The purpose of this investigation was to determine the prevalence of AIIS dysmorphism based on specimen sex, race, and age, while introducing a novel anatomic-based classification system.

Methods: A total of 1,797 adult cadaveric specimens (n = 3,594 hemipelvises) were analyzed. AIIS with the potential for subspine impingement (SSI) was recorded in each specimen by two independent authors. Specimens with AIIS dysmorphism were then reexamined to determine SSI subtype using a novel descriptive anatomic classification system.

Results: AIIS dysmorphism was present in 6.4% (n = 115 of 1,797 specimens) of specimens and 5.2% (n = 186 of 3,594) of hemipelvises. Dysmorphism was significantly more common in male specimens (p = 0.04) and African–American specimens (p = 0.04). No significant overall difference in prevalence was appreciated based on specimen age (p = 0.89). Subtype classification found that 67% of hemipelvises possessed a columnar type AIIS, 30% were bulbous and 3% hook type. Males possessed a significantly higher prevalence of columnar type AIIS dysmorphism (p < 0.001). No significant overall differences in anatomic classification were appreciated based on race (p = 0.12) or when analyzed based on age (p = 0.34).

Conclusion: AIIS dysmorphism was present in 6.4% of the 1,797 cadaveric specimens evaluated. African-American and male specimens possessed significantly higher prevalence of AIIS dysmorphism, with no significant difference based on specimen age. Columnar type AIIS dysmorphism was most common. Anatomic classification was not significantly different based on specimen race or age.

Level of Evidence: Case Series, Level IV.

Lack of Abdominal Stability and Control as a Possible Contributor to Rectus Femoris Avulsion Fracture in the Adolescent Soccer Player: A Case Report

PURPOSE

To describe evaluation and physical therapy treatment for an athlete who is male and 13 years old with healing bilateral rectus femoris avulsion fractures.

SUMMARY OF KEY POINTS

Fractures of the anterior inferior iliac spine may be linked to poor abdominal stability in soccer athletes who are male and an adolescent. The development and use of an abdominal stability screening tool could be an efficient and effective way to determine fracture risk and guide prevention programs.

CONCLUSIONS AND RECOMMENDATIONS FOR CLINICAL PRACTICE

Following 8 weeks of conservative physical therapy treatment, the athlete met all goals and returned to pain-free soccer activities without residual impairments. Four months following discharge, he reported full participation in soccer competition without complications. This case illustrates that abdominal weakness is a potential risk factor for anterior inferior iliac spine avulsion fracture. Screening for abdominal weakness and incorporating preventative programs into training regimens is recommended to prevent anterior inferior iliac spine injuries in this population.

Hip Impingement after Anterior Inferior Iliac Spine Avulsion Fractures: A Case Report with Review of the Literature

Avulsion fractures of the anterior inferior iliac spine (AIIS) are rare injuries in adolescent athletes. We present a case of a 15-year-old male who sustained an avulsion injury to his right AIIS when kicking a soccer ball. The patient had chronic pain and extra-articular subspinal impingement leading to decreased hip flexion and rotation. The injury occurred 1.5 years prior to symptom onset, and we were the first health care providers to manage the injury. We attempted six months of nonoperative management including activity modifications and nonsteroidal anti-inflammatory (NSAID) therapy without improvement. Although this injury can often be managed nonoperatively, his symptoms required excision of the AIIS and associated heterotopic ossification. He had an excellent outcome with return to soccer and no pain at his final follow-up visit two years after surgery. Due to the limited literature guiding the surgeon's management of AIIS avulsion injuries with associated heterotopic ossification, we provide a review of the literature detailing pre- and postoperative ranges of motion, surgical approach, fixation or excision of the avulsion fragment, and return to sport in this patient population.

Subspinal impingement: clinical outcomes of arthroscopic decompression with one year minimum follow up

PURPOSE

This study was designed to (1) evaluate the clinical outcomes after arthroscopic subspinal decompression in patients with hip impingement symptoms and low AIIS, and to (2) assess the presence of low anterior inferior iliac spine on the pre-operative radiographs of patients with established subspinal impingement diagnosed intra-operatively.

METHODS

Retrospective analysis of patients who underwent arthroscopic subspinal decompression has been performed. The indications for surgery were femoroacetabular impingement (FAI), or subspinal impingement. Pre-operative radiographs were assessed for anterior inferior iliac spine type. Intra-operative diagnosis of low anterior inferior iliac spine was based on the level of anterior inferior iliac spine extension relative to the acetabulum and the presence of reciprocal labral and chondral lesions. In patients where low anterior inferior iliac spine was not diagnosed on pre-operative radiographs, the pre-operative radiographs were re-read retrospectively to assess missed signs of low anterior inferior iliac spine.

RESULTS

Thirty-four patients underwent arthroscopic subspinal decompression between 2012 and 2015. The patients were followed for a median of 25 months (13-37 months). Intra-operatively, grade 2 anterior inferior iliac spine was found in 27 patients and grade 3 anterior inferior iliac spine was found in 7 patients. MHHS, HOS, and HOSS scores increased from median (range) pre-operative scores of 55 (11-90), 48 (20-91) and 20 (0-80) to 95 (27-100), 94 (30-100) and 91 (5-100), respectively (p < 0.0001, p = 0.001, p < 0.0001, respectively). Pre-operative diagnosis of low AIIS was made in 6/34 patients via AP radiographs. On retrospective analysis of pre-operative radiographs, signs of low AIIS were still not observed in 21/34 (61.8%) patients.

CONCLUSIONS

Arthroscopic subspinal decompression of low AIIS yielded significantly improved outcome measures and high patient satisfaction at a minimum of 13 months follow-up. Low AIIS is often under-diagnosed on AP pelvis and lateral frog radiographs and if left untreated, may result in unresolved symptoms and failed procedure.

LEVEL OF EVIDENCE

IV.

Biomechanical Comparison of Anterograde and Retrograde Lesser Trochanter Avulsion Repair

Background:

Lesser trochanter avulsions are rare injuries in adolescents. Severe cases with relevant fragment displacement can be treated surgically. However, no standard approach is available in the literature. Operative techniques are presently limited to anterograde fixations. A new retrograde approach to reduce operative difficulty and postoperative morbidity has been proposed. So far, no biomechanical comparison of these techniques is available.

Hypothesis:

Retrograde repair of the lesser trochanter with a titanium cortical button will produce superior stability under load to failure and similar displacement under cyclic loading compared with anterograde fixation with titanium suture anchors.

Study Design:

Controlled laboratory study.

Methods:

Sixteen paired hemipelvic cadaveric specimens (mean age, 62.5 ± 10.7 years) were dissected to isolate the lesser trochanter and iliopsoas muscle. After repair of a simulated lesser trochanter avulsion, specimens were tested under cyclic loading between 10 and 125 N at 1 Hz for 1500 cycles before finally being loaded to failure at a rate of 120 mm/min in a material testing machine. Motion tracking was used to assess displacement at the superior and inferior aspects of the iliopsoas tendon under cyclic loading.

Results:

Load to failure was significantly greater for the retrograde repair compared with the anterograde repair (1075.24 ± 179.39 vs 321.85 ± 62.45 N; P = .012). Mean displacement at the superior repair aspect (retrograde vs anterograde: 3.29 ± 1.84 vs 4.39 ± 4.50 mm; P = .779) and mean displacement at the inferior aspect (3.54 ± 2.13 vs 4.22 ± 4.48 mm; P = .779) of the iliopsoas tendon did not significantly differ by the type of repair. Mode of failure was tendon tearing by the sutures for each retrograde repair and anchor pullout for each anterograde repair.

Conclusion:

Surgical repair of lesser trochanter avulsion fractures with retrograde fixation using a titanium cortical button demonstrated superior load to failure and similar displacement under cyclic loading compared with anterograde fixation using suture anchors.

Clinical Relevance:

The retrograde approach provides a biomechanically validated alternative to other surgical techniques for this injury.

Arthroscopic Reduction and Fixation of a Lesser Trochanter Avulsion Nonunion

Identifying and treating avulsion fractures of the pelvis and proximal femur in adolescent athletes has become increasingly more important as the rate of competitive sports participation has grown. The majority of these fractures can be treated conservatively, with most returning to full activity. Surgical treatment of these injuries has been traditionally indicated for >2 cm displacement, painful nonunion, symptomatic exostosis formation, or persistent pain and symptoms. Lesser trochanter avulsion injuries are extremely rare and literature outlining their surgical treatment lacking. We present our method of arthroscopic reduction and fixation of lesser trochanter avulsion nonunions.

The prevalence of a prominent anterior inferior iliac spine

INTRODUCTION

Impingement of the prominent anterior inferior iliac spine (AIIS) against the femoral neck has recently been described as another type of impingement. The purpose of this study is to provide a distribution of AIIS types using the classification proposed by Hetsroni and thus report on the prevalence of prominent types.

MATERIALS AND METHODS

A total of 400 patients were included in the study with an average age 27.3 ± 6.9 years (range 18-40). All patients received a whole-body polytrauma computer tomography (CT) scan in the emergency room (ER) upon arrival. The classification of AIIS proposed by Hetsroni et al., which describes three morphological types, was used. Type II and III were grouped as prominent types. The measurements were performed in all three planes by two examiners.

RESULTS

Male to female ratio was 71:29. Type I was observed in 367 (91.7%) patients. Type II was observed in 31 (7.8%) patients and type III was observed in 2 (0.5%) patients, unilaterally. Prominent types were much more prevalent in men (10.5%) than in women (2.6%). The CT assessment demonstrated excellent intra- and interreliability (overall: 0.926, I/II: 0.906, III: 1.000).

CONCLUSION

A young population demonstrates a prevalence of a prominent AIIS of 11.5%. Prominent AIIS is more common in men than in women.

Operative Treatment of Proximal Rectus Femoris Injuries in Professional Soccer Players: A Series of 19 Cases

Background:

Proximal rectus femoris (PRF) tears are relatively rare injuries among top-level athletes. PRF injuries can be avulsions of both tendon heads (direct and reflected heads) or of a single head, and some have a tendency to progress to recurrent injuries.

Purpose:

To describe a series of operatively treated PRF ruptures in professional soccer players.

Study Design:

Case series; Level of evidence, 4.

Methods:

Nineteen cases of PRF injuries (18 patients, 1 bilateral) in professional soccer players who were treated surgically were retrospectively reviewed. Perioperative findings with return-to-play data were recorded.

Results:

Of the PRF injuries, 10 total avulsions (both heads) and 9 single-head tears were seen on magnetic resonance imaging and were later confirmed during surgery. All 18 patients returned to their preinjury level of play (mean follow-up, 2.8 years [range, 1-11 years]).

Conclusion:

The repair of PRF tears in professional soccer players yielded good results and allowed all patients to return to their preinjury level of play.

Revisiting the Anteroinferior Iliac Spine: Is the Subspine Pathologic? A Clinical and Radiographic Evaluation

BACKGROUND

Subspine impingement is a recognized source of extraarticular hip impingement. Although CT-based classification systems have been described, to our knowledge, no study has evaluated the morphology of the anteroinferior iliac spine (AIIS) with plain radiographs nor to our knowledge has any study compared its appearance between plain radiographs and CT scan and correlated AIIS morphology with physical findings. Previous work has suggested a correlation of AIIS morphology and hip ROM but this has not been clinically validated. Furthermore, if plain radiographs can be found to adequately screen for AIIS morphology, CT could be selectively used, limiting radiation exposure.

QUESTIONS/PURPOSES

The purposes of this study were (1) to determine the prevalence of AIIS subtypes in a cohort of patients with symptomatic femoroacetabular impingement; (2) to compare AP pelvis and false profile radiographs with three-dimensional (3-D) CT classification; and (3) to correlate the preoperative hip physical examination with AIIS subtypes.

METHODS

A retrospective study of patients undergoing primary hip arthroscopy for femoroacetabular impingement syndrome was performed. Between February 2013 and November 2016, 601 patients underwent hip arthroscopy. To be included here, each patient had to have undergone a primary hip arthroscopy for the diagnosis of femoroacetabular impingement syndrome. Each patient needed to have an interpretable set of plain radiographs consisting of weightbearing AP pelvis and false profile radiographs as well as full documentation of physical findings in the medical record. Patients who additionally had a CT scan with 3-D reconstructions were included as well. During the period in question, it was the preference of the treating surgeon whether a preoperative CT scan was obtained. A total of 145 of 601 (24%) patients were included in the analysis; of this cohort, 54% (78 of 145) had a CT scan and 63% (92 of 145) were women with a mean age of 31 ± 10 years. The AIIS was classified first on patients in whom the 3-D CT scan was available based on a previously published 3-D CT classification. The AIIS was then classified by two orthopaedic surgeons (TGM, MRK) on AP and false profile radiographs based on the position of its inferior margin to a line at the lateral aspect of the acetabular sourcil normal to vertical. Type I was above, Type II at the level, and Type III below this line. There was fair interrater agreement for AP pelvis (κ = 0.382; 95% confidence interval [CI], 0.239-0.525), false profile (κ = 0.372; 95% CI, 0.229-0.515), and 3-D CT (κ = 0.325; 95% CI, 0.156-0.494). There was moderate to almost perfect intraobserver repeatability for AP pelvis (κ = 0.516; 95% CI, 0.284-0.748), false profile (κ = 0.915; 95% CI, 0.766-1.000), and 3-D CT (κ = 0.915; 95% CI, 0.766-1.000). The plane radiographs were then compared with the 3-D CT scan classification and accuracy, defined as the proportion of correct classification out of total classifications. Preoperative hip flexion, internal rotation, external rotation, flexion adduction, internal rotation, subspine, and Stinchfield physical examination tests were compared with classification of the AIIS on 3-D CT. Finally, preoperative hip flexion, internal rotation, and external rotation were compared with preoperative lateral center-edge angle and alpha angle.

RESULTS

The prevalence of AIIS was 56% (44 of 78) Type I, 39% (30 of 78) Type II, and 5% (four of 78) Type III determined from the 3-D CT classification. For the plain radiographic classification, the distribution of AIIS morphology was 64% (93 of 145) Type I, 32% (46 of 145) Type II, and 4% (six of 145) Type III on AP pelvis and 49% (71 of 145) Type I, 48% (70 of 145) Type II, and 3% (four of 145) Type III on false profile radiographs. False profile radiographs were more accurate than AP pelvis radiographs for classification when compared against the gold standard of 3-D CT at 98% (95% CI, 96-100) versus 80% (95% CI, 75-85). The false profile radiograph had better sensitivity for Type II (97% versus 47%, p < 0.001) and specificity for Types I and II AIIS (97% versus 53%, p < 0.001; 98% versus 90%, p = 0.046) morphology compared with AP pelvis radiographs. There was no correlation between AIIS type as determined by 3-D CT scan and hip flexion (rs = -0.115, p = 0.377), internal rotation (rs = 0.070, p = 0.548), flexion adduction internal rotation (U = 72.00, p = 0.270), Stinchfield (U = 290.50, p = 0.755), or subspine tests (U = 319.00, p = 0.519). External rotation was weakly correlated (rs = 0.253, p = 0.028) with AIIS subtype. Alpha angle was negatively correlated with hip flexion (r = -0.387, p = 0.002) and external rotation (r = -0.238, p = 0.043) and not correlated with internal rotation (r = -0.068, p = 0.568).

CONCLUSIONS

The findings in this study suggest the false profile radiograph is superior to an AP radiograph of the pelvis in evaluating AIIS morphology. Neither preoperative hip internal rotation nor impingement tests correlate with AIIS type as previously suggested questioning the utility of the AIIS classification system in identifying pathologic AIIS anatomy.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Impingement around the hip: beyond cam and pincer

In this review, we bring to the attention of the reader three relatively unknown types of hip impingement. We explain the concept of low anterior inferior iliac spine (AIIS) impingement, also known as sub-spine impingement, ischio-femoral impingement (IFI) and pelvi-trochanteric impingement. For each type of impingement, we performed a search of relevant literature.We searched the PubMed, Medline (Ovid) and Embase databases from 1960 to March 2016. For each different type of impingement, a different search strategy was conducted.In total, 19 studies were included and described. No data analysis was performed since there was not much comparable data between studies.An overview of symptoms, clinical tests and possible surgical treatment options for the three different types of extra-articular impingement is provided.Several disorders around the hip can cause similar complaints. Therefore, we plead for a standardized classification. In young and athletic patients, in particular, there is much to gain if hip impingement is diagnosed early. Cite this article: EFORT Open Rev 2018;3:30-38. DOI: 10.1302/2058-5241.3.160068.

Pediatric avulsion fractures of pelvis: current concepts

PURPOSE OF REVIEW

Provide the reader with an evidence-based update on the importance of accurate diagnosis of commonly missed avulsion fractures of pelvis apophyses, the necessary imaging studies, the feared complications and the recent treatment recommendations.

RECENT FINDINGS

Accurate diagnosis of avulsion fractures of pelvis apophyses is high yield as misdiagnosis leads to improper treatment. They should be differentiated from muscle strain and apophysitis. These fractures are usually associated with good outcomes; however, missed diagnosis can lead to further displacement, nonunion, functional limitation, femoroacetabular impingement and infection. A/P and frog lateral pelvis radiograph show the fracture and its displacement in the majority of cases. Conservative treatment, consisting of a short period of rest and immobilization followed by passive stretching then progressive resisted activity before return to sports, is recommended in minimally displaced avulsions. Surgical treatment is favored in displaced fractures (>15 mm), as it is associated with quicker return to sports.

SUMMARY

Treating physicians should keep a high index of suspicion in pediatric and adolescent patients presenting with typical clinical exam findings. Pelvic Anteroposterior and frog leg radiographs are often diagnostic. Missed diagnosis can aggravate the prognosis of a usually benign condition. Adequate medical or surgical treatment should then be administered.

Operative Fixation of an Anterior Inferior Iliac Spine Apophyseal Avulsion Fracture Nonunion in an Adolescent Soccer Player: A Case Report

CASE

A 14-year-old male competitive soccer player presented with a history of recurrent right hip pain for 18 months. He was diagnosed with an anterior inferior iliac spine (AIIS) apophyseal avulsion fracture nonunion with subspinal impingement, which was confirmed by radiographs, computed tomography, and magnetic resonance imaging. The patient underwent surgical fixation and subspinal decompression. He returned to competitive soccer 5 months postoperatively.

CONCLUSION

AIIS apophyseal avulsion fractures occur in adolescent athletes and generally respond to nonoperative treatment. When such management is unsuccessful, surgical fixation can lead to resolution of pain with return of full function.

Anterior Inferior Iliac Spine Deformity as a Cause for Extra-articular Hip Impingement in Young Athletes After an Avulsion Fracture: A Case Report

Extra-articular hip impingement from prior traumatic injury to the anterior inferior iliac spine (AIIS) is an uncommon cause of groin pain in young athletes. Currently, the most common treatment for this injury is arthroscopic decompression. However, hip arthroscopy is not universally available and requires advanced skills. We report 2 cases of the development of extra-articular hip impingement from unusual bony exostoses off the AIIS after traumatic injury in 2 young athletes who underwent open surgical resection. The multidisciplinary sports medicine team should be aware of the development of extra-articular impingement from traumatic injury to the AIIS and that open surgical resection is a viable alternative to arthroscopic decompression.

Avulsion of the Anterior Inferior Iliac Spine Rehabilitation in a Rural Private Practice

An unusual case is presented of an 11-year-old girl presenting for treatment to a semirural private physical therapy practice, not specializing in pediatric care, following an avulsion fracture of the anterior inferior iliac spine. The patient presented initially non-weight-bearing, with little hip movement due to pain. Following treatment, the patient returned to preinjury status including return to full participation in netball. A review of the literature regarding healing and rehabilitation is described. Concepts of neuromuscular retraining were integrated in the rehabilitation program. Recent evidence demonstrates deficiencies in hip and knee control for girls between 11 and 15 years of age. Evidence suggests that these deficiencies may be a precursor to injury and poor outcomes in lower extremity injuries in this patient group.

Arthroscopic Treatment of a Displaced Nonunion of the Anterior Inferior Iliac Spine Causing Extra-articular Impingement

This report describes a case of nonunion of an anterior inferior iliac spine (AIIS) apophyseal avulsion fracture with resultant subspine impingement combined with symptomatic femoroacetabular impingement (FAI). A 16-year-old male soccer player presented with a 6-month history of right groin pain exacerbated by kicking and running. The patient was diagnosed with a displaced nonunion of the AIIS apophysis avulsion fracture causing secondary extra-articular impingement beyond cam-type FAI by physical examination and radiological findings. The authors performed arthroscopic AIIS decompression, with concurrent FAI correction and labral repair and capsular closure. At 4 months after surgery, a radiograph and a computed tomography scan showed complete bony union of the AIIS apophyseal nonunion. Modified Harris Hip Sore and Nonarthritic Hip Score improved from 74.8 and 61, respectively, to 100 for both at final follow-up. The effectiveness of arthroscopic decompression of the AIIS as part of a comprehensive minimally invasive surgery including FAI correction and labral repair resulted in complete union of the AIIS and pain-free return to sport and bony union. [Orthopedics. 2017; 40(4):e725-e728.].

Operative versus conservative treatment of apophyseal avulsion fractures of the pelvis in the adolescents: a systematical review with meta-analysis of clinical outcome and return to sports

BACKGROUND

Avulsion fractures of the pelvic apophyses typically occur in adolescent athletes due to a sudden strong muscle contraction while growth plates are still open. The main goals of this systematic review with meta-analysis were to summarize the evidence on clinical outcome and determine the rate of return to sports after conservative versus operative treatment of avulsion fractures of the pelvis.

METHODS

A systematic search of the Ovid database was performed in December 2016 to identify all published articles reporting outcome and return to preinjury sport-level after conservative or operative treatment of avulsion fractures of the pelvis in adolescent patients. Included studies were abstracted regarding study characteristics, patient demographics and outcome measures. The methodological quality of the studies was assessed with the Coleman Methodology Score (CMS).

RESULTS

Fourteen studies with a total of 596 patients met the inclusion criteria. The mean patient age was 14.3 ± 0.6 years and 75.5% of patients were male. Affected were the anterior inferior iliac spine (33.2%), ischial tuberosity (29.7%), anterior superior iliac spine (27.9%), iliac crest (6.7%) lesser trochanter (1.8%) and superior corner of the pubic symphysis (1.2%). Mean follow-up was 12.4 ± 11.7 months and most of the patients underwent a conservative treatment (89.6%). The overall success rate was higher in the patients receiving surgery (88%) compared to the patients receiving conservative treatment (79%) (p = 0,09). The rate of return to sports was 80% in conservative and 92% in operative treated patients (p = 0,03). Overall, the methodological quality of the included studies was low, with a mean CMS of 41.2.

CONCLUSION

On the basis of the present meta-analysis, the overall success and return to sports rate was higher in the patients receiving surgery. Especially in patients with fragment displacement greater 15 mm and high functional demands, surgical treatment should be considered.

Subspine Hip Impingement: An Unusual Cause of Hip Pain in an Elite Weightlifter

Anterior hip pain can be difficult to diagnose due to the many pathologies and overlapping pain patterns that exist in the hip region. Clinical findings of pain at the anterior inferior iliac spine with passive hip flexion, proximal quadriceps pain and weakness, and painful impingement tests of the hip may be indicative of subspine hip impingement. This report describes the diagnosis and treatment of anterior hip pain, including subspine impingement and femoroacetabular impingement in an elite weightlifter. This case also describes how with the correct diagnosis and treatment, the athlete returned to play to her previous level of sport 11 months after a complex hip injury.

Anterior Inferior Iliac Spine (AIIS) and Subspine Hip Impingement

BACKGROUND

Abnormal morphology of the anterior inferior iliac spine (AIIS) and the subspine region of the acetabular rim are increasingly being recognised as a source of symptomatic extra-articular hip impingement. This review article aims to highlight important differences in the pathogenesis, clinical presentation and management of extra-articular hip impingement from both the AIIS and subspine bony regions, and the outcome following surgical intervention.

METHODS

A literature review was undertaken to examine the supporting evidence for AIIS and subspine hip impingement. A narrative account of the Author's professional experience in this area, including operative technique for arthroscopic correction, is also presented.

RESULTS

Abnormal morphology of the AIIS and subspine region has been classified using cadaveric, radiological and arthroscopic means; the clinical presentation and operative treatment has been documented in several case series studies. Dual pathology is often present - recognition and treatment of both intra- and extra-articular components are necessary for good postoperative outcome.

CONCLUSIONS

AIIS and sub-spine hip impingement should be considered as distinct pathological entities, which may also co-exist. Symptom relief can be expected following arthroscopic deformity correction with the treatment of concomitant intra-articular pathology. Failure to recognise and treat the extra-articular component may affect postoperative outcome.

LEVEL OF EVIDENCE

V.

Apophyseal injuries in children's and youth sports

INTRODUCTION

The authors reviewed the current English literature regarding apophyseal injuries affecting young athletes, to highlight the frequency and characteristics of these injuries, to clarify risk factors and specific prevention measures, and to identify future research objectives.

SOURCES OF DATA

The authors performed a comprehensive search of the medical literature, using the Medline database, including all English articles. Various combinations of the Keywords 'injury', 'sports', 'athletic injuries', 'avulsion fractures', 'physeal', 'physis', 'apophysis', 'apophysitis', 'growth plate' were used.

AREAS OF AGREEMENT

Growth benefits from a moderate physical activity.

AREAS OF CONTROVERSY

Growth deficit may occur in young athletes involved in intensive practice of sport following apophysitis.

GROWING POINTS

Apophyseal injuries occurring during sport are less common than overall rate of injuries affecting the adolescent population. Growth disturbance occurs only rarely after an apophyseal injury.

AREAS TIMELY FOR DEVELOPING RESEARCH

Further studies should consider analytical as well as descriptive components of apophyseal injuries, to allow the identification of new possible risk factors and preventive measures and to help early detection and proper treatment as well.

Extra-articular hip impingement due to heterotopic ossification formation at the anterior inferior iliac spine following previous pelvic external fixation

Femoroacetabular impingements (FAIs), specifically cam type and pincer type, continue to be accepted as causes of intra-articular hip pathology and sources of hip pain. Reports of other causes of hip impingement including extra-articular causes have surfaced recently. One structure of importance is the anterior inferior iliac spine (AIIS) due to its inconsistent bony morphology and the pull of the rectus femoris muscle putting it at risk for an avulsion fracture. Under certain circumstances, open surgical excision of exostosis formation after an avulsion fracture of the AIIS has been used. The case below represents a clinical scenario in which a medically unstable and multiply injured trauma patient had an external pelvic fixator placed as part of the treatment plan for an unstable pelvic injury. Following this pelvic external fixation treatment, the patient went on to develop clinically significant heterotopic bone formation at the AIIS pin site with extra-articular hip impingement syndrome.

Proximal Rectus Femoris Avulsion Repair

Proximal rectus femoris tendon avulsions are rare and occur mostly in male athletes. Currently, the standard of care for complete tendinous avulsions of the direct arm of the rectus femoris is nonoperative treatment. However, surgical repair may be considered in high-level athletes who have a high demand for repetitive hip flexion performed in an explosive manner or in patients in whom nonoperative treatment has failed. The purpose of this technical note is to describe the method for surgical repair of the proximal direct arm of the rectus femoris to its origin at the anterior inferior iliac spine using suture anchors.

Arthroscopic Resection of a Large Bony Exostosis Arising from the Anterior Inferior Iliac Spine Causing Extra-articular Hip Impingement: A Case Series

INTRODUCTION

Abnormal morphology of the anterior inferior iliac spine (AIIS) is a rarely recognized but important source of extra-articular hip impingement. Chronic progressive symptoms of stiffness and limitation of hip motion with persistent groin pain may place significant restriction on activity. Concomitant femoroacetabular impingement is often present but recognition and effective treatment of the uncommon extra-articular component is important for successful outcome.

CASE REPORT

Three cases of symptomatic extra-articular hip impingement secondary to AIIS deformity and in conjunction with mild underlying femoroacetabular impingement (FAI) are presented. They include two athletic Caucasian males aged 27 and 35-years old with a history of prior rectus tendon injury and secondary bony exostosis formation and a 53-year-old Caucasian male with a nontraumatic, developmental AIIS deformity. In all cases, an excellent clinical outcome with a full return to pain free activity was achieved postoperation. Their clinical presentation, diagnosis and post-operative outcome at 1.5-2 years (mean 1.7 years) following arthroscopic AIIS resection are discussed.

CONCLUSION

Arthroscopic management of AIIS extra-articular hip impingement has been rarely reported and the longer-term outcome is unknown. We report the successful clinical outcome in a case series of three patients up to 2 years following arthroscopic AIIS resection. This case series demonstrates the sustainable benefits of arthroscopic correction of AIIS bony exostosis as a cause of extra-articular FAI.

Hip impingement: beyond femoroacetabular

In the last 20 years, femoroacetabular impingement has been at the forefront of clinical practice as a cause of hip pain in young adults. As arthroscopic techniques for the hip continue to evolve, the possible presence of a new group of conditions creating mechanical conflict in and around the hip joint (ischiofemoral, subspine and iliopsoas impingement) has recently been elucidated whilst interest in already known 'impingement' syndromes (pelvic-trochanteric and pectineofoveal impingement) is now revived. This article attempts to increase awareness of these relatively uncommon clinical entities by describing their pathomorphology, contact mechanics, treatment and published results available to present. It is hoped that such knowledge will diversify therapeutic options for the clinician, thereby improving outcomes in a small but not negligible portion of patients with previously unexplained persistent symptoms.

Large ossification mass causing groin pain and limited hip function

Acute avulsion fractures to the anterior inferior iliac spine are unusual, yet well documented injuries, especially in the adolescent skeleton. To our knowledge, chronic avulsion fracture to the anterior inferior iliac spine has not been reported. This report presents a case of chronic avulsion fracture to the anterior inferior iliac spine leading to a large ossification mass resulting in a late presentation of hip with limited function. Surgical excision followed by physiotherapy led to satisfactory resolution of pain and significantly improved the range of flexion.

Anterior inferior iliac spine avulsion fracture: a series of 5 cases

Avulsion fractures of the pelvic apophyses rarely occur in adolescent athletes in the course of sudden strong contraction of muscle attached to growth cartilage. This injury may usually be misdiagnosed for tendon or muscle strain. Patient's history, physical examination, and radiologic studies are important for diagnosis. The literature includes only a few case reports but no case series as yet. The aim of this study was to present the results of 5 cases of anterior inferior iliac spine (AIIS) avulsion fractures treated conservatively. The study included 5 patients (4 male, 1 female, mean age 13.6 years) who underwent conservative treatment for AIIS avulsion fractures and had an adequate follow-up. All patients were admitted to the emergency department and misdiagnosed as muscle strain. Three of them were football player, 1 skier, and 1 fighter. Each patient was treated with immobilization and nonsteroidal anti-inflammatory drugs. At follow-up, all patients showed relief from their pain and mechanical symptoms and regained full range of motion and returned to their previous levels of activity. Diagnosis requires careful attention to the physical examination and imaging. In this series, all pelvic avulsion fractures (100%) were managed successfully with a conservative approach. Good results and return to previous levels of activity can be achieved with conservative treatment.

A Unique Rectus Femoris Injury in an Adolescent Professional Soccer Player: A Case Report

CASE

A sixteen-year-old professional soccer player presented with persistent pain in the right thigh of two years' duration and the inability to return to play. Evaluation revealed a chronic rupture of the rectus femoris muscle. Because physiotherapy and rehabilitation failed to help, a surgical repair was performed. He returned to his previous activity level within nine months after surgery.

CONCLUSION

Rupture of the proximal part of the rectus femoris should be acknowledged in the differential diagnosis, especially when presenting with persistent pain in the anterior aspect of the thigh lasting more than one year. Delayed repair might be recognized as a reasonable option for chronic rupture of the proximal part of the rectus femoris.

An anatomical study of the acetabulum with clinical applications to hip arthroscopy

BACKGROUND

The clock face has been employed to define the position of labral pathology in relation to identifiable arthroscopically relevant acetabular landmarks. The purpose of this study was to qualitatively and quantitatively describe arthroscopically relevant anatomy of the acetabulum. We aimed to present a surgical landmark that is located in close proximity to the usual location of labral pathology as an alternative to the midpoint of the transverse acetabular ligament as a reference point.

METHODS

Fourteen fresh-frozen cadaveric hemipelves were dissected to evaluate osseous landmarks and relevant surrounding soft-tissue structures of the acetabulum. With use of a coordinate-measuring device, we determined the location, orientation, and relationship of key arthroscopic landmarks and the footprint areas formed by the insertions of the rectus femoris, capsule, and labrum.

RESULTS

An analysis of variability of reference points around the acetabulum in relation to the anterior inferior iliac spine (AIIS) revealed that the superior margin of the anterior labral sulcus (psoas-u) was the most consistent anatomic landmark. The AIIS comprised superior and inferior facets, demarcated by the origins of the direct head of the rectus femoris and the iliocapsularis. The inferolateral corner of the footprint of the direct head of the rectus femoris was located 19.2 mm (95% confidence interval [CI], 18.0 to 20.4 mm) from the acetabular rim and the inferolateral aspect of the iliocapsularis footprint, 12.5 mm (95% CI, 10.1 to 15.0 mm) from the rim.

CONCLUSIONS

The superior margin of the anterior labral sulcus (psoas-u) was a reliable landmark for reference of the clock face on the acetabulum. We propose that this point, denoting 3:00, be adopted as the new standard clock-face reference for intra-articular hip structures because of its universal presence and reliable arthroscopic visualization. This marker is also beneficial because of its proximity to the typical location of labral pathology. The data presented provide a comprehensive analysis of pertinent arthroscopically relevant acetabular anatomy.

CLINICAL RELEVANCE

The establishment of a new standard reference point within the acetabulum will enhance the consistency of interpretation of the location of labral pathology and improve arthroscopic orientation and navigation.

Arthroscopically assisted fixation of the lesser trochanter fracture: a case series

Avulsion fractures of the lesser trochanter in adolescents are uncommon. This injury is a result of a sudden forceful contraction of the iliopsoas tendon. It usually occurs during vigorous sport activity. Historically, these injuries were treated non-operatively, with guarded results, including weak hip flexor strength and non-union, hindering return to competitive sport. We report a series of three arthroscopically assisted fracture fixations performed by the senior author, using cannulated screw fixation in two cases and an anchor in one case. Mobilization was commenced immediately following surgery, allowing weight bearing as tolerated using crutches for 4 weeks, thereafter unaided walking was allowed. Patients were assessed at 2 weeks, 6 weeks, 3 months and 1-year post-operatively. Radiographs were utilized to confirm full union. All three patients were able to mobilize unaided by 4 weeks post-operatively and two of the three patients returned to competitive sport at 3 months. Near—anatomical union was achieved in all cases. No complications were noted during surgery and the peri-operative period in our series. The utilization of arthroscopic reduction and fixation of avulsion of the lesser trochanter results in good fixation and allows a faster recovery with a return to sports activity, and therefore, we suggest it as a viable treatment option for such injuries.

Extra-articular hip impingement: a systematic review examining operative treatment of psoas, subspine, ischiofemoral, and greater trochanteric/pelvic impingement

PURPOSE

Extra-articular hip impingement can be the result of psoas impingement (PI), subspine impingement (SSI), ischiofemoral impingement (IFI), and greater trochanteric/pelvic impingement (GTPI). Symptoms may be due to bony abutment or soft-tissue irritation, and often, it is a challenge to differentiate among symptoms preoperatively. Currently, the clinical picture and diagnostic criteria are still being refined for these conditions. This systematic review was conducted to examine each condition and elucidate the indications for, treatment options for, and clinical outcomes of surgical management.

METHODS

We searched online databases (Medline, Embase, and PubMed) for English-language clinical studies published from database inception through December 31, 2013, addressing the surgical treatment of PI, SSI, IFI, and GTPI. For each condition, 2 independent assessors reviewed eligible studies. Descriptive statistics are presented.

RESULTS

Overall, 9,521 studies were initially retrieved; ultimately, 14 studies were included examining 333 hips. For PI, arthroscopic surgery resulted in 88% of patients achieving good to excellent results, as well as significant improvements in the Harris Hip Score (P = .008), Hip Outcome Score-Activities of Daily Living (P = .02), and Hip Outcome Score-Sport (P = .04). For SSI, arthroscopic decompression, with no major complications, resulted in a mean 18.5° improvement in flexion range of motion, as well as improvements in pain (mean visual analog scale score of 5.9 points preoperatively and 1.2 points postoperatively) and the modified Harris Hip Score (mean of 64.97 points preoperatively and 91.3 points postoperatively). For both IFI and GTPI, open procedures anecdotally improved patient symptoms, with no formal objective outcomes data reported.

CONCLUSIONS

This review suggests that there is some evidence to support that surgical treatment, by arthroscopy for PI and SSI and by open surgery for IFI and GTPI, results in improved patient outcomes.

LEVEL OF EVIDENCE

Systematic review of Level IV and V (case report) studies.

Avulsion fracture of the anterior inferior iliac spine mimicking a bone tumor: a case report

This is a case of a 17-year-old boy who was admitted to the clinic suffering from right hip-inguinal region pain which began after a soccer match. He had an avulsion fracture in the anterior inferior iliac spine and CT/MR images showed similarities to a bone tumor. These fractures are especially seen in the apophyses which are within the ossification process. The radiological appearance of these fractures during the healing period may be involved with bone tumors. In the control MRI of the patient after one year, the fracture was almost healed completely. Treatment is generally conservative. Good results have been reported with rest, analgesic and anti-inflammatory drugs. Familiarity with radiological findings of these avulsion fractures in this region not only protects the patient from invasive procedures but also avoids the involvement of the practitioner in legal consequences resulting from a misdiagnosis of sarcoma.

The recognition and evaluation of patterns of compensatory injury in patients with mechanical hip pain

Context:

In active individuals with femoroacetabular impingement (FAI), the resultant reduction in functional range of motion leads to high impaction loads at terminal ranges. These increased forces result in compensatory effects on bony and soft tissue structures within the hip joint and hemipelvis. An algorithm is useful in evaluating athletes with pre-arthritic, mechanical hip pain and associated compensatory disorders.

Evidence Acquisition:

A literature search was performed by a review of PubMed articles published from 1976 to 2013.

Level of Evidence:

Level 4.

Results:

Increased stresses across the bony hemipelvis result when athletes with FAI attempt to achieve supraphysiologic, terminal ranges of motion (ROM) through the hip joint required for athletic competition. This can manifest as pain within the pubic joint (osteitis pubis), sacroiliac joint, and lumbosacral spine. Subclinical posterior hip instability may result when attempts to increase hip flexion and internal rotation are not compensated for by increased motion through the hemipelvis. Prominence of the anterior inferior iliac spine (AIIS) at the level of the acetabular rim can result in impingement of the anterior hip joint capsule or iliocapsularis muscle origin against the femoral head-neck junction, resulting in a distinct form of mechanical hip impingement (AIIS subspine impingement). Iliopsoas impingement (IPI) has also been described as an etiology for anterior hip pain. IPI results in a typical 3-o’clock labral tear as well as an inflamed capsule in close proximity to the overlying iliopsoas tendon. Injury in athletic pubalgia occurs during high-energy twisting activities in which abnormal hip ROM and resultant pelvic motion lead to shearing across the pubic symphysis.

Conclusion:

Failure to recognize and address concomitant compensatory injury patterns associated with intra-articular hip pathology can result in significant disability and persistent symptoms in athletes with pre-arthritic, mechanical hip pain.

Strength-of-Recommendation Taxonomy (SORT):

B

The association between avulsions of the reflected head of the rectus femoris and labral tears: a retrospective study

BACKGROUND

The aim of this study was to investigate if an association existed between the reflected head of rectus femoris avulsion injuries and labral tears in pediatric patients referred for magnetic resonance arthrography (MRA) or magnetic resonance imaging (MRI) evaluation.

METHODS

Electronic medical records of the patients between the ages of 12 and 18 who were treated at the hospitals affiliated by McMaster University between June 2000 and November 2010 with a diagnosis of rectus femoris avulsion injuries were retrospectively identified and analyzed. Patients were included if they had magnetic resonance imaging or MRA images of their hip.

RESULTS

Nine patients with avulsion injuries of the rectus femoris muscle were identified. The patient population consisted of 4 females and 5 males (range, 8 to 17 y, mean age 14 y). All injuries occurred during sports activity, which included running and kicking during soccer, skating in hockey, and a squatting exercise. MRA examination of 7 of these patients demonstrated associated labral tears. All patients were initially treated conservatively. Five patients continued to sustain from residual pain in the 9 months after the initial injury. Two of these patients with significant refractory pain were subsequently treated with hip arthroscopy. Intraoperatively, 1 small labral tear and 1 labral avulsion were identified and treated.

CONCLUSIONS

This study suggests that there may be an association between avulsion of the reflected head of rectus femoris and labral injuries and that there may be an underlying spectrum of traction injuries. Patients with rectus femoris avulsion injuries with persistent symptoms may be at risk for concurrent traumatic labral tears.

LEVEL OF EVIDENCE

Level 4, retrospective case series.

Hip arthroscopy for extra-articular hip disease

The increasing popularity and success of hip arthroscopy has led to the development of related techniques for treating hip pathologies external to the joint proper. These minimally invasive endoscopic procedures serve in a diagnostic role to complement clinical evaluations and offer a therapeutic alternative to traditional open techniques. The indications for extra-articular hip endoscopy continue to expand. Recent literature describes applications for treating greater trochanteric pain syndrome, internal snapping hip, deep gluteal syndrome, and subspine impingement and for diagnosing and treating extra-articular sources of hip pain in patients who have undergone hip arthroplasty.

Peri-articular diseases of the hip: emerging frontiers in arthroscopic and endoscopic treatments

The precise diagnosis of both intra and extra-capsular disease of the hip is now possible because of commonly available advanced diagnostic imaging techniques. An increasing number of reports in the orthopedic literature describe new endoscopic and arthroscopic techniques to address peri-articular pathology of the hip. The purpose of this paper is to review current techniques in the management of extra-articular hip conditions.

Peripheral compartment as the initial access for hip arthroscopy in complex cases: technical note

When performing arthroscopic procedures, the hip joint is divided into central and peripheral compartments. Currently, both compartments are evaluated in most of the procedures, but the procedures are usually started by accessing the central compartment. When a direct approach to the central compartment is significantly impeded, it is necessary to perform the initial arthroscopic approach to the hip from the peripheral compartment using either an intracapsular technique or an extracapsular technique. The technical pearls that might be required in these patients are discussed, and typical clinical cases are presented.

The anterior inferior iliac spine: size, position, and location. An anthropometric and sex survey

PURPOSE

The purpose of this study was to investigate and describe the size, location, and position of the anterior inferior iliac spine (AIIS) in normal individuals.

METHODS

We reviewed 50 computed tomography (CT) scans of 50 patients without hip pain or pathologic features. Mean patient height was 169.8 cm (women, 163 cm; men, 176.8 cm) and mean weight was 69.6 kg (women, 63.8 kg; men, 75.4 kg). We used all scans to measure both the left and right AIIS for the anatomic description of 100 AIISs. We measured AIIS dimensions, specifically length, width, and height. We also measured vertical, horizontal, and straight distances between the most anteroinferior prominence of the AIIS and the acetabular rim. We normalized AIIS size and distances from the acetabular rim according to the patient's height and body mass index (BMI). We also assessed the version of the AIIS using 2 angles. The first angle was the angle between the AIIS midaxis line and a plumb line, and the second angle was calculated as the angle subtended by the AIIS midaxis line and the ilium midaxis line.

RESULTS

There were no significant differences between the AIIS in men and women in all measurements (except the width of the AIIS) when normalized to the patient's height and BMI. There were no significant differences in AIIS dimensions when comparing side-to-side differences in the entire study population.

CONCLUSIONS

In quantifying AIIS dimensional size, distance from the anterior acetabular rim, and version, this study found no significant difference in all measurements normalized to patient size (height and BMI) between the left and right sides, and no significant sex difference was found in AIIS measurements, except the width of the AIIS.

CLINICAL RELEVANCE

Morphologic variations that deviate from these normal values may help the clinician identify cases of subspinal impingement.

Anterior inferior iliac spine deformity as an extra-articular source for hip impingement: a series of 10 patients treated with arthroscopic decompression

PURPOSE

To describe an arthroscopic technique for decompression of a prominent anterior inferior iliac spine (AIIS) leading to extra-articular hip impingement and to provide short-term outcome after this procedure.

METHODS

We retrospectively reviewed office charts, imaging studies, operative reports, arthroscopic images, preoperative and postoperative hip flexion range of motion, and preoperative and postoperative modified Harris Hip Scores in a consecutive series of 10 male patients who had arthroscopic decompression of symptomatic AIIS deformities leading to extra-articular hip impingement. The procedure was performed through standard anterolateral and mid-anterior hip arthroscopy portals that were also used to explore the joint and address concomitant intra-articular pathologies.

RESULTS

The mean age was 24.9 years, with 8 of 10 patients aged younger than 30 years. In 9 patients, an anterior cam lesion was identified and decompressed before the AIIS decompression. The mean follow-up time was 14.7 months (range, 6 to 26 months). Hip flexion range of motion improved from 99° ± 7° before surgery to 117° ± 8° after surgery (P < .001). The modified Harris Hip Score improved from 64 ± 18 before surgery to 98 ± 2 at latest follow-up after surgery (P < .001).

CONCLUSIONS

Arthroscopic decompression of a symptomatic AIIS deformity is a reproducible procedure that can provide excellent outcomes at short-term follow-up. As opposed to using an open approach for decompressing a prominent AIIS, an arthroscopic approach may be of particular value in patients with mixed intra- and extra-articular sources of hip dysfunction, because it enables the surgeon to address all pathologies with a single arthroscopic procedure.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Hip avulsion fractures

An avulsion fracture is a separation of a small fragment of a bone cortex at the site of a ligament or tendon attachment. It is commonly seen in adolescent athletes. The mechanism of injury is either a sudden violent muscular contraction or an excessive amount of muscle stretch across an open epiphysis. This may also occur where the bone has been weakened by osteoporosis or local lesion. The common sites of avulsion injuries are the tibial tubercle and the medial epicondyle. However, hip avulsion fractures are not uncommon. They may occur in adolescents, young adults and in elderly people. There are various protocols for management depending on the patient’s age, mechanism of injury and the underlying pathology.

Adolescent femoroacetabular impingement from malunion of the anteroinferior iliac spine apophysis treated with arthroscopic spinoplasty

This article describes a case of an acute anterior inferior iliac spine apophyseal avulsion fracture in an adolescent athlete progressing to secondary symptomatic femoroacetabular impingement from an inferiorly displaced malunion and its arthroscopic management. A 13-year-old boy with an acute minimally displaced avulsion fracture of the anterior inferior iliac spine apophysis had initial symptomatic improvement with conservative treatment and a 3-month symptom-free period but then developed flexion-induced deep anterior groin pain and mechanical symptoms. Radiographs confirmed an inferiorly displaced malunion of the ipsilateral anterior inferior iliac spine apophysis in addition to acetabular retroversion and cam deformity. Surgical treatment, including arthroscopic spinoplasty, was performed. Despite some nonrestrictive heterotopic ossification, the patient had a successful clinical outcome at 18 months, with return to football, and a nonarthritic hip score of 98. Although anterior inferior iliac spine avulsion fractures have historically been considered relatively self-limiting injuries, their malunion may be a previously missed cause of unrelenting or bimodal pain from secondary femoroacetabular impingement with possible degenerative consequences in young athletic patients. Anterior inferior iliac spine avulsion fractures may merit a lower degree of tolerance for displacement in the acute setting and a higher degree of clinical and radiographic scrutiny with surgical intervention, possibly in the form of arthroscopic spinoplasty in the more chronic one.

Surgical treatment of proximal ruptures of the rectus femoris in professional soccer players

INTRODUCTION

Muscle injuries are very common in athletes. Depending on the type of sport, muscle injuries represent approximately 9-54% of total injuries. The rectus femoris muscle is very important in specific sports, such as soccer and American football, because it is the muscle involved in movements, such as sprinting and kicking the ball. Therefore, we believe that these disabling injuries need special and prompt treatment to enable athletes to return to their sporting activities.

AIM

The aim of our study is to assess the results of surgical treatment of ruptures of the rectus femoris in professional soccer players by reattachment of the tendon. We identified ten proximal rectus femoris ruptures in professional soccer players belonging to the Spanish Football League.

RESULTS

Mean follow-up was 34.8 months (SD + 28.72). The mean age of the players was 27.4 years (SD + 4.14). In six cases (60%), the tendon was repaired by direct suture with non-absorbable sutures. In four cases, where there had been complete avulsion, bone anchoring sutures were used. There is no consensus regarding the optimal treatment for ruptures of the rectus femoris muscle. There are a few reports in the literature based on isolated experiences of different surgeons.

CONCLUSION

Surgical treatment has a lower recurrence rate in our hands; we believe that surgical treatment is indicated in these cases, for a complete functional recovery for professional soccer players.