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

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.

Apophyseal Avulsion of the Rectus Femoris Tendon Origin in Adolescent Soccer Players

Apophyseal avulsions of the rectus femorus tendon (RFT) at the anterior inferior iliac spine (AIIS) can occur in adolescents, often while performing soccer. Patient-reported outcomes (PROMs) and time to return to sport of these patients are relatively unknown. Therefore, the aim of this study was to assess the PROMs and return to sports of patients with AIIS avulsions and compare the results with those reported in the literature. This is a case series of seven consecutive patients presenting at our hospital between 2018 and 2020 with an apophyseal avulsion of the RFT from the AIIS. The patients were assessed with use of the WOMAC and Tegner scores and return to sports was evaluated. All patients were male soccer players (median age 13 years; range, 12–17). They were all initially treated non-operatively. One of the patients subsequently needed excision surgery of a heterotopic ossification because of non-transient hip impingement. All other patients recovered after a period of relative rest. Median time to return to sports was 2.5 months (range, 2–3). At a median follow-up of 33 months (range, 18–45), the WOMAC (median, 100; range, 91–100) and Tegner scores (median, 9; range, 5–9) were high. In accordance with the existing literature, most patients with apophyseal avulsions of the AIIS recover well with non-operative treatment. However, the avulsion can lead to hip impingement due to heterotopic ossifications possibly needing surgical excision. Sport resumption is achievable after 2–3 months, and patient-reported outcomes are highly satisfactory in the long term.

[Apophyseal avulsion in the pelvic region in childhood and adolescence]

BACKGROUND

The importance of the apophyseal plates during growth is often underestimated. They act as a muscular insertion and influence the joint mechanics by the load-dependent change in shape.

PATHOMECHANISMS

An anatomically functional adaptation occurs as protection from overloading. In special kinds of sports with highly dynamic movements, sudden changes of direction and eccentric/concentric muscle activities the resulting stress may exceed the strength of the apophyseal plate. In adolescence this results in a total or partial tearing of the apophysis in the sense of an avulsion injury. In the pelvic region the ischial tuberosity, the anterior superior and inferior iliac spine are mainly affected.

DIAGNOSTICS

The medical history and clinical diagnostics are supplemented by conventional radiographic imaging. Sectional imaging diagnostics are usually unnecessary.

TREATMENT

Conservative management by reduced (partial) weight bearing and physiotherapy represents the gold standard in treatment. In cases with a fragment displacement >1.5-2.0 cm and in competitive athletes an open reduction should be considered.

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.

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.