Introduction
Ischial tuberosity apophyseal avulsion fractures (ITAFs) are rare injuries that occur primarily in adolescent athletes.1 ITAFs usually occur during jumping and sprinting, as a forceful eccentric hamstring contraction avulses the ischial apophysis before it is fully fused, which occurs around age 21 in males.2,3 The majority of ITAFs occur in boys (76-82%) at an average age of 14.4 Although ITAFs only comprise 19% of pelvic apophyseal injuries, they are a well-recognized entity in adolescent athletes and should be included in the differential diagnosis of acute posterior thigh or buttock pain for this group.5,6 Prompt recognition is critical, as delayed or insufficient treatment can lead to nerve entrapment, chronic pain, and functional deficits.7
ITAFs typically present with an acute onset of pain localized to the proximal posterior thigh. Patients often report feeling a “pop” upon injury, with ensuing difficulties ambulating and pain exacerbated by hip flexion.8 Hallmark exam findings of ITAFs include edema, ecchymosis and tenderness over the ischial tuberosity, discomfort with sitting, and pain with hip or knee movement.
The sciatic nerve lies approximately 1.2 cm laterally from the ischial tuberosity and, therefore, is susceptible to irritation by scar tissue or the displaced fragment.9 Accompanying nerve injury classically presents as radicular symptoms and discomfort during hip extension, adduction, and external rotation.7
Treatment of ITAFs and proximal hamstring ruptures depends on injury severity, displacement of the fracture and/or proximal hamstring, and presence of neurological injury. Treatment of partial hamstring tears and minimally displaced ITAFs is often non-surgical, including an early rest phase followed by physical therapy three weeks post-injury.10 Surgical intervention is recommended in cases of fracture displacement greater than 2 cm, in the presence of neurological symptoms, or for nonunion after failed conservative treatment.11,12
Current literature does not support a definitive superior technique for surgical fixation. Options include screw fixation, suture anchors, and cortical suspensory buttons.13 This case report presents a novel hybrid fixation technique for a proximally and anteriorly displaced ITAF with neurologic symptoms in an adolescent athlete.
Case Presentation
Ethical Considerations
The patient and his legal guardian were informed that data concerning the case would be submitted for publication, and his legal guardian agreed. A copy of the signed consent form has been uploaded as a supplementary file. As the case report is devoid of patient identifiable information, it is exempt from IRB review requirements, in agreement with the policies of the University of Virginia Institutional Review Board for Health Sciences Research.
Presentation
A 13-year-old male with no pertinent past medical history presented with left posterior thigh pain after he felt “a pop” during a twisting movement while playing lacrosse. The pain was localized to his proximal posterior thigh and worsened with sitting. He initially presented to an outside hospital, where a pelvic radiograph, computed tomography (CT) scan, and magnetic resonance imaging (MRI) demonstrated a left ITAF, displaced 3 cm anteriorly, proximally, and laterally (Figure 1). Non-surgical management was recommended by the outside provider.
The patient presented to our clinic 16 days after his injury for a second opinion with posterior thigh ecchymoses, pain about the ischial tuberosity, limited hip flexion secondary to pain, and paresthesias of the lower extremity. Given the avulsed fragment’s displacement and presence of neurologic symptoms, surgical intervention was recommended to minimize the risk of symptomatic nonunion, sciatic nerve irritation, and hip impingement.
Management
Nineteen days after the injury (three days after presentation to our clinic), the patient underwent an ischial tuberosity open reduction and internal fixation, proximal hamstring repair, and sciatic nerve neurolysis. The patient was placed under general anesthesia, in the prone position on a regular operating room bed. A 5.5 cm transverse skin incision was made within the gluteal crease. The gluteus maximus was carefully retracted, and the avulsed bony fragment of the ischial tuberosity was identified by palpation. The fragment was scarred into place and immobile upon identification. The posterior femoral cutaneous and sciatic nerves were identified and neurolysed to ensure there was no adherence to the ischial tuberosity fragment. The fragment was then mobilized using blunt dissection to restore native anatomic positioning. The bare ischial tuberosity donor site was prepared with a curette and rongeur to promote a healing bed for reattachment of the avulsion fragment and hamstring.
For hybrid fixation, two 4.75 mm anchors (corkscrew; Arthrex, Inc., Naples, FL, USA) were placed into the ischial tuberosity donor site, one proximal and one distal. One suture limb from each anchor was passed in Krakow fashion through the proximal hamstring attached to the avulsed ischial tuberosity fragment (Figure 2). The additional suture limbs were then passed in simple fashion through the proximal hamstring, allowing the proximal hamstring and avulsed ischial tuberosity fracture to be reduced to the tuberosity donor site. Fluoroscopy was used to confirm the appropriate reduction of the avulsion fracture before tying the sutures from the anchors. After sufficient reduction, a K-wire was placed in the central aspect of the fracture fragment. The K-wire was then over drilled, the depth was measured, and a 4.5-cannulated screw was placed for definitive fixation. At the conclusion of the case, the sciatic nerve was visualized and found to be free from the repair with no apparent damage or tension. Fracture alignment was confirmed radiographically.
Outcome
The patient tolerated the procedure well, without complications. For the first two weeks after surgery, he was toe-touch weight bearing in a hinged knee brace with a 30-degree extension block with the use of crutches. He was instructed to avoid active knee flexion or hip extension movements. Radiographs at the two-week follow-up visit revealed maintained fracture alignment without evidence of hardware complications. He reported completely resolved lower extremity paresthesias and progressed to 50% weight bearing in addition to progressing his knee extension while in the prone position.
Seven weeks postoperatively, he had progressed to ambulating without an assistive device and was no longer wearing his knee brace. He had fluid movement of the left hip with no pain. Plain radiographs from this appointment demonstrated continued healing of the left ITAF in anatomic alignment without evidence of hardware complication.
From seven weeks postoperatively until three months, he worked on muscle-strengthening exercises. Four months postoperatively, he began jogging with a progression to running. At five months postoperatively, he was cleared for a full return to sport. At one-year follow-up, he noted no complaints and said he fully participated in the lacrosse season with no lower extremity symptoms limiting his performance. Imaging at this appointment revealed a fully healed ITAF (Figure 3).
Conclusion
This case contributes to the limited body of literature on adolescent ITAFs requiring surgical fixation. While most injuries can typically be managed conservatively, surgery is indicated in cases with greater than 2 cm of fracture displacement, in the presence of neurological symptoms, or with nonunion after conservative treatment.10,11 This patient demonstrated a markedly displaced fracture fragment with associated sciatic nerve paresthesias, necessitating surgical intervention.
Nonoperative management of ITAFs may increase the risk of nonunion with subsequent ischiofemoral impingement, hamstring dysfunction, and sciatic nerve irritation.7,12 Additionally, the ischial apophysis, like other growth plates, is often rapidly replaced by fibrous tissue following an injury, resulting in the formation of a “bony bar” or bone bridge.13 Therefore, surgical intervention should occur soon after injury to avoid scarring as seen in this case.14 Surgical intervention is not without risk, however, including general surgical complications, sciatic nerve injury, wound complications, and hardware-related issues.11
Several fixation techniques have been described for the surgical treatment of ITAFs, including screws, suture anchors, and cortical suspensory buttons, among others. However, there is no established gold standard of treatment. To our knowledge, only one prior published case commented on the use of a hybrid fixation construct, combining a screw and suture anchors, to treat an ITAF. That report lacked operative detail and was part of a larger series.15 In that study, no statistically significant difference in postoperative complications was found between fixation types.
Various surgical approaches have been described for the treatment of ITAFs, including longitudinal, subgluteal, and transverse gluteal incisions. A longitudinal or vertical incision may allow for improved visualization, particularly for distally displaced avulsion fractures or retracted hamstring injuries.3,16,17 However, this approach may cause greater visible scarring and soft tissue disruption. A Kocher-Langenbeck approach to the acetabulum has also been utilized to treat ITAFs, although this technique is quite extensile, necessitates splitting or detachment of the gluteus maximus muscle, and may not provide ideal access to the ischial tuberosity, which is at the distal portion of the exposure.18,19
In this case, a limited transverse gluteal incision was selected for several reasons. First, the fragment in our patient was displaced proximally. Therefore, more distal exposure would not provide additional benefit but could have led to complications, including delayed wound healing and heterotopic ossification.17 Secondly, a limited transverse gluteal incision provides for improved cosmesis, although care should be taken with neurolysis and fracture mobilization through a narrower working window.16
The favorable outcome in this case suggests that timely hybrid fixation with nerve decompression can provide a stable repair and symptom resolution, thereby supporting a safe and efficient return to sport in skeletally immature athletes with significantly displaced ITAF and neurologic involvement. Further studies are needed to determine whether this approach significantly improves outcomes over alternative fixation techniques for this patient population. Specifically, long-term outcomes data may clarify whether hybrid fixation offers advantages in healing rates, risk of neurovascular injury, or re-injury risk compared to traditional fixation constructs.
Acknowledgments
None
Authors’ Contributions
Ben M. Setaro drafted and edited the manuscript. Dominic M. Farronato assisted with writing and editing. Richard F. Nauert and Bryce N. Clinger contributed to data collection. Charles A. Su conceived the study, collected data, supervised the project, and provided revisions to the manuscript. All authors read and approved the final version of the manuscript.
Disclosures
The authors have no conflicts of interest to disclose.
Funding/Presentation
This work was supported by the University of Virginia Department of Orthopaedic Surgery and has not been presented previously.