A 14 year old boy suffered from severe pain in the left hip region after school sports. The definite diagnosis was made by MRI and a conservative therapy was initiated.
A 14 year old boy developed severe pain above the left hip during school sports when playing soccer. Physical examination revealed a localised pain in the left inguinal area with a painfull tenderness. Flexion of the hip was painfully reduced. Radiography of the pelvis revealed a prominent anterior inferior iliac spine. A MRI of the hip on a 1.0T Siemens Harmony scanner was performed and an avulsion fracture of the apophysis of the anterior inferior iliac spine was diagnosed. Therapy strategy remained conservative with bed rest and analgesia and stepwise mobilization.
Pelvic apophyseal fractures typically affect adolescents after a sudden contraction of a muscle to the immature musculo-skeleton junction [1]. Avulsion fractures of the pelvis were found in approximately 16% of pelvic injuries that required a pelvic x-ray [2]. Among these lesions those of the anterior inferior iliac spine have been described as second frequently avulsion fractures (21,5%). The injury mechanism is a combination of a sudden hip hyperextension and knee flexion leading to maximum stress on the physis at the attachment of the rectus femoris muscle. This is the weakest part of this osseotendinous junction in young adults. These movements are observed by kicking a ball (soccer), jumping over hurdles and gymnastics [1, 2].
Diagnosis of theses lesions is made by ultrasound, CT or MRI while X-ray is usually without pathological findings [3]. X-ray in our case did not reveal any osseous lesion except from a slight prominence of the left anterior inferior iliac spine (Fig. 1, 2) while T2 weighted and T1 weigted fat saturated MRI sequences revealed fluid surrounding and osseous oedema within this structure (Fig. 3, 4) as well as the distracted osseous fragment (Fig. 5).
Sonographically widening of the physis or slight displacement of the apophysis in comparison to the contralateral side with oedema or hemorrhage indicate an avulsion fracture [4]. CT usually proves the alvusion fragment while hematoma and oedema are striking on MRI images [3, 4].
Treatment is generally conservative. Sufficient analgesia and bed rest are administered in the acute stage followed by stepwise mobilization afterwards for 3 weeks to 4 months until full function and painlessness is reached [1, 3, 5]. If a severe distraction of the fracture is diagnosed or conservative management fails surgical reattachment of the dislocated fragment is the method of choice [5].
Left sided pelvic apophyseal fracture.
Based on the provided imaging data of the Anterior Inferior Iliac Spine (AIIS) region, the following main features can be observed:
Considering the patient's age, type of physical activity (e.g., playing soccer or hurdling), clinical presentation (acute hip pain), and MRI findings (bony avulsion fragment and surrounding edema), the most likely diagnosis is:
Left Anterior Inferior Iliac Spine Avulsion Fracture
Once an avulsion fracture is confirmed, the treatment approach depends on the degree of fragment displacement and symptom severity:
After initial treatment, an individualized rehabilitation plan should be developed, aiming to facilitate fracture healing, restore hip and lower limb strength, and prevent re-injury.
Rehabilitation/Exercise Prescription Recommendations:
Throughout the rehabilitation process, refer to the FITT-VP principle (Frequency, Intensity, Time, Type, Volume, Progression, and Individualization). Adjust the plan based on the patient's reported pain, functional progress, and follow-up imaging findings.
This report is based on the provided clinical history and imaging data and is intended to offer reference information for diagnosis and treatment. It does not replace a formal in-person consultation or the final medical opinion of a qualified physician.
Left sided pelvic apophyseal fracture.
