Complications of Hip Endoscopy in the Treatment of Subgluteal Space Pathologies

MR Neurography of the Lumbosacral Plexus: Technique and Disease Patterns

The lumbosacral plexus (LSP) comprises a complex network of nerves supplying the pelvis and lower extremities and may be affected by a wide range of diseases. Lumbosacral plexopathy can be challenging to diagnose due to overlapping clinical presentations and difficulty performing electrodiagnostic testing of the deep pelvic structures. MRI-more specifically, MR neurography (MRN)-can readily depict most LSP segments. MRN techniques, preferably performed at 3.0 T, continue to evolve, with most protocols including two-dimensional and optionally three-dimensional, heavily T2-weighted fat-suppressed sequences. This article provides technical tips for optimizing LSP MRN, as well as an overview of various LSP-related pathologic conditions, with accompanying illustrative examples. ©RSNA, 2025 Supplemental material is available for this article. See the invited commentary by Chhabra in this issue.

Endoscopic Lesser Trochanter Excision for Ischiofemoral Impingement

Background

Ischiofemoral impingement (IFI) is a rare yet underrecognized cause of posterior hip, low back/sacroiliac region, and deep gluteal pain. Patient anatomy, including femoral anteversion, coxa valga, posterior pelvic tilt, and lumbar stiffness, contributes to symptomatic IFI.

Indications

Indications for surgical intervention include exclusion of alternative causes of posterior gluteal pain, failed nonoperative intervention including physical therapy and injection targeting the ischiofemoral space, and narrow ischiofemoral distance with quadratus femoris edema with or without sciatic nerve entrapment and protection of hamstring repair.

Technique Description

Our preferred technique includes endoscopic lesser trochanter (LT) excision through a posterior approach in the prone position. The patient is positioned with the hips in slight flexion and the knees at 60° of flexion to take tension off the sciatic nerve. Fluoroscopy is used to localize the LT for 4 planned portal sites, creating a diamond around the LT: 2 for sciatic nerve retraction, 1 for endoscopic visualization, and 1 for working. The sciatic nerve is identified, bluntly mobilized, and protected. Radiofrequency ablation is used to dissect through the quadratus femoris from the posterior-central LT and expose the posterior LT. A 5.5-mm diamond-tip bur is then used to fully excise the LT flush with the femoral cortex. The patient is kept touch-down weightbearing for 6 weeks to reduce the risk of proximal femur stress fracture.

Results

Endoscopic LT excision has been widely reported as a reliable method to increase ischiofemoral distance and relieve mechanical bone impingement and sciatic nerve entrapment. In our experience, the posterior approach in the prone position allows for maximum visualization to identify and protect the neurovascular structures, completely excise the LT, and treat concomitant pathology.

Conclusions

Our preferred technique for surgical treatment of IFI with posterior endoscopic LT excision in the prone position is safe based on sciatic nerve visualization and effective with complete LT excision.

Patient Consent Disclosure Statement

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Stress Fracture after Arthroscopic Lesser Trochanter Resection: Diagnosis and Therapy

We report on the case of a 52-year-old female who presented with a stress fracture after undergoing an endoscopic resection of the lesser trochanter in ischiofemoral impingement, which was resistant to maximal conservative treatment. To the best of our knowledge, this complication has not been previously described. Non-weight-bearing and intravenous alendronic acid were prescribed for management. No additional surgery was required. The patient was pain free with the ability to perform sports on the same level as before and had no complaints.

Systematic Review of Complications Associated With Proximal Hamstring Tendon Repair

Background

Although several complications of proximal hamstring tendon ruptures have been reported in the literature, few studies have comprehensively analyzed the complication profile of proximal hamstring tendon repair.

Purpose

To identify the overall rate of complications following proximal hamstring tendon repair and to differentiate these complications into categories.

Study Design

Systematic review; Level of evidence, 4.

Methods

Included in this review were studies that examined surgical repair of proximal hamstring tendon ruptures; all studies were in English and had an evidence level of 4 or higher. No restrictions were made regarding publication date or methodological quality. Data regarding complications were extracted to calculate the overall complication rate as well as the rate of major and minor complications. A quantitative data synthesis was conducted using the chi-square test to compare the proportion of patients who experienced complications with the endoscopic versus open approach.

Results

A total of 43 articles including 2833 proximal hamstring tendon repairs were identified. The overall postoperative complication rate was 15.3% (n = 433). The rate of major complications was 4.6%, including a 1.7% rate of sciatic nerve injury, 0.8% rate of venous thromboembolism, 0.8% reoperation rate, 0.8% rerupture rate, and 0.4% rate of deep infection. Minor complications included a 2.4% rate of posterior femoral cutaneous nerve injury, 2.3% rate of persistent hamstring myopathy, 2.2% rate of persistent sitting pain, 1.8% rate of peri-incisional numbness, 1.1% rate of superficial infection, and 0.8% rate of hematoma/seroma.

Conclusion

Proximal hamstring tendon repair is associated with an overall complication rate of 15.3%, including a 4.6% rate of major complications.

Open Ischiofemoral Impingement Decompression

Ischiofemoral impingement is a relatively rare cause of posterior hip pain associated with narrowing of the space between the lateral aspect of the ischium and the lesser trochanter. Symptoms typically consist of lower buttock, groin, and/or medial thigh pain, which is commonly exacerbated by adduction, extension, and external rotation of the hip. This condition can be treated nonoperatively in many circumstances; however, recalcitrant cases may require surgical intervention. Whereas described operative treatment options for this pathology range from endoscopic to open procedures, this Technical Note describes a safe and reliable technique for open ischiofemoral decompression with sciatic nerve neurolysis through a posterior approach for treatment of ischiofemoral impingement refractory to conservative treatment.

Endoscopic Sciatic Neurolysis for Deep Gluteal Space Syndrome

Background

Deep gluteal syndrome (DGS) encompasses a spectrum of pathologies causing symptomatic sciatic nerve compression deep to the gluteus maximus muscle. Endoscopic sciatic neurolysis is an option for management of DGS when conservative treatment fails.

Indications

Endoscopic sciatic neurolysis is indicated for retro-trochanteric pain, sciatica-like burning in the posterior thigh, and sitting discomfort that is reproducible on physical examination after failing conservative management.

Technical Description

The technique presented here introduces a standard endoscopic sciatic neurolysis technique with an accessory posterolateral portal placed distally and in line with the sciatic nerve. Use of a switching stick through an accessory distal posterolateral portal can allow for in-line protection and retraction of the sciatic nerve while it is carefully released from compressive fibrous bands using an arthroscopic shaver. It is important that the accessory portal be placed under direct visualization with caution not to injure the sciatic nerve. An arthroscopic radiofrequency device can be used for hemostasis and further release of fibrous bands. At the end of the procedure, the sciatic nerve should be visualized fully released and freely mobile from the piriformis muscle to the level of the lesser trochanter.

Results

In properly selected patients, the procedure is very successful. In a series of 35 cases, the procedure reduced sitting pain (present in 97% of patients preoperative, 17% of patients postoperative), reduced narcotic use, improved visual analog scale (VAS) pain scores, and improved modified Harris hip scores without major complications.

Discussion

Although rare following hip arthroscopy, postoperative scarring and fibrous bands are a common cause of DGS which can be effectively treated by endoscopic sciatic nerve decompression. Results of endoscopic sciatic neurolysis have thus far been encouraging with improvements in patient reported outcome scores and high rates of satisfaction. However, complications do occur and can result in neurologic deficits. Nevertheless, with careful patient selection and meticulous sciatic nerve dissection, endoscopic sciatic neurolysis for DGS is a safe and effective technique for decompression of fibrous bands and adhesions that can lead to sciatic neuralgia.

Editorial Commentary: Subgluteal Hip Arthroscopy for Sciatic Nerve Entrapment, Ischiofemoral Impingement, or Proximal Hamstring Tears: Beyond the Comfort Zone

Advancements in hip arthroscopy are astounding. Circumferential labral reconstruction, labral augmentation, and capsular reconstruction are valuable tools. Beyond the "comfort zone" of the hip intra-articular realm, new frontiers include the peritrochanteric space, and a similarity to the subacromial space of the shoulder makes the transition attainable. In contrast, the subgluteal space is seen as outside the box. Sciatic nerve entrapment (SNE), ischiofemoral impingement (IFI), and tears of the proximal origin of the hamstring are among the subgluteal space pathologies. Clinical assessment of deep gluteal syndrome, defined as nondiscogenic sciatic nerve entrapment, can be particularly difficult but is critical and one of the skills that we as hip sports surgeons need to master. The respective treatments for SNE, IFI, and hamstring tears are nerve decompression, lesser trochanteric resection, and hamstring repair. Complications can occur, most commonly temporary injury of the sciatic nerve and permanent injury of the posterior femoral cutaneous nerve. While all located in the deep gluteal space, SNE, IFI, and proximal hamstring tears are unique entities. When thinking outside the box, it's important to consider the complicated contents of Pandora's box.