Ischiofemoral impingement and hamstring dysfunction as a potential pain generator after ischial tuberosity apophyseal fracture non-union/malunion

Sagittal Pelvic Tilt Directly Influences the Ischiofemoral Space: A Cadaveric Study

BACKGROUND

Ischiofemoral impingement (IFI) is understood to be a pain generator in the deep gluteal space. Femoral position is known to influence the ischiofemoral space (IFS), but there has been no study examining the effect of sagittal pelvic tilt on the IFS. The purpose of this study was to determine whether changes in pelvic tilt in the sagittal plane lead to changes in the dimensions of the IFS.

MATERIALS AND METHODS

Five fresh frozen cadavers (10 hips) were used for this anatomic study. The specimens were skeletonized and placed in the prone position with the pelvis fixed to a custom-built hinged table. A digital inclinometer was used to tilt the pelvis -10°, 0°, and 10° simulating posterior, neutral, and anterior pelvic tilt, respectively. Digital calipers were used to measure the dimensions of the IFS in all three positions of sagittal pelvic tilt.

RESULTS

Changes in pelvic tilt resulted in significant changes in the dimensions of the IFS. Mean IFS dimensions measured 29.3±9.7 mm, 37.2±9.0 mm, and 24.3±9.2 mm in the neutral, anterior, and posterior pelvic tilt positions, respectively (P<.0001).

CONCLUSION

Changes in sagittal pelvic tilt influence the dimensions of the IFS, with posterior pelvic tilt noted to significantly decrease the IFS when compared with neutral and anterior pelvic tilt. These findings suggest that further evaluation of sagittal spinopelvic balance in the etiology of symptomatic IFI may be warranted. [Orthopedics. 2024;47(3):167-171.].

Outcomes following adolescent athlete proximal hamstring apophyseal avulsion bone fragment excision and direct tendon-ischial tuberosity reattachment

Apophyseal proximal hamstring bone avulsion is uncommon, occurring in adolescents following sudden forceful contraction of the musculotendinous unit. It can be severely disabling, preventing return to sport. This study assessed outcome following avulsed bone excision and direct hamstring tendon-ischial tuberosity reattachment using bone anchors. Validated hamstring-specific Sydney hamstring orthopaedic research evaluation PROMs were prospectively collected from consecutively treated athletes (7 elite and 11 recreational) by a single surgeon over 13 years. Outcomes at 1-year and final follow-up for primary acute surgery at less than 3 months after injury (group 1), primary chronic surgery at more than 3 months after established nonunion (group 2) and revision following failed screw fixation (group 3) were analyzed with sport participation and level at 1 year. Sixteen primary and two revision procedures were analyzed. Mean injury age was 14.6 years (SD, 1.8). Combined primary mean injury scores improved from 11.89 (SD, 7.32) to 33.31 (SD, 2.30) and showed mean 1 year and final follow-up scores within 0.3-6.1% of preinjury values. Pronounced improvement occurred from injured scores for groups 1 versus 2, respectively at 1 year by 247.7% versus 59.0% and at final follow-up by 251.0% versus 64.1%, for groups 1 versus 2, respectively. Final outcome scores of group 3 were high. All cases returned to preinjury sport level by 1 year and indicated satisfaction to repeat treatment. No significant complications occurred. As the largest series to assess outcomes following this surgical technique, success is highlighted by high score improvements close to preinjury values and return to preinjury sport level.

What Factors Are Associated With Postoperative Ischiofemoral Impingement After Bernese Periacetabular Osteotomy in Developmental Dysplasia of the Hip?

BACKGROUND

Any abnormal structures that contribute to the narrowing of the ischiofemoral space could induce ischiofemoral impingement. Bernese periacetabular osteotomy (PAO) medializes the hip center and, therefore, decreases contact stress on the cartilage in developmental dysplasia of the hip (DDH). However, medialization of the hip center might also narrow the ischiofemoral space, which may increase the risk of postoperative ischiofemoral impingement in patients with acetabular dysplasia who are undergoing PAO. Furthermore, the dysplastic hip has less ischiofemoral space and less space for the quadratus femoris. A few studies have focused on the amount of medialization of the hip center, but the proportion of postoperative ischiofemoral impingement after PAO has not been investigated.

QUESTIONS/PURPOSES

(1) What proportion of patients develop ischiofemoral impingement after undergoing unilateral PAO for DDH? (2) What radiographic factors are associated with postoperative ischiofemoral impingement in patients who underwent PAO for DDH? (3) How much hip center medialization is safe so as to avoid postoperative ischiofemoral impingement during PAO?

METHODS

Between 2014 and 2016, we treated 265 adult patients who had symptomatic residual acetabular dysplasia (lateral center-edge angle less than 20°) using PAO. During that time, we generally offered PAO to patients with acetabular dysplasia when the patients had no advanced osteoarthritis (Tönnis grade < 2). Of those, we considered only patients who underwent primary PAO without femoral osteotomy as potentially eligible. Based on that, 65% (173 of 265) were eligible; a further 9% (24 of 265) were excluded due to leg length discrepancy, spine disorders, or joint replacement in the contralateral side, and another 6% (17 of 265) of patients were lost before the minimum study follow-up of 2 years or had incomplete datasets, leaving 50% (132 of 265) for analysis in this retrospective study at a mean of 2.70 ± 0.71 years. The diagnosis of ischiofemoral impingement was defined by symptoms, MRI, and diagnostic ischiofemoral injection. We ascertained the percentage of patients with this diagnosis to answer the first research question. To answer the second question, we divided the patients into two groups: PAO patients with ischiofemoral impingement and PAO patients without ischiofemoral impingement. The demographic data and preoperative imaging parameters of patients in both groups were compared. There were statistical differences in acetabular version, ischial angle, neck-shaft angle, the presence of positive coxa profunda sign, McKibbin index, ischiofemoral space, quadratus femoris space, anterior acetabular section angle, and the net amount of hip center medialization. To investigate potential factors associated with postoperative ischiofemoral impingement in patients who underwent PAO, these factors underwent binary logistic regression analysis. To answer the third question, the cutoff value of the net amount of hip center medialization was evaluated using receiver operator characteristic curve and the Youden index method.

RESULTS

We found that 26% (35 of 132) of PAO dysplastic hips had postoperative ischiofemoral impingement. After controlling for confounding variables such as acetabular version, ischial angle, femoral neck version, McKibbin index, and ischiofemoral space, we found that an increasing neck-shaft angle (odds ratio 1.14 [95% confidence interval 1.01 to 1.29]; p = 0.03), a positive coxa profunda sign (OR 0.13 [95% CI 0.03 to 0.58]; p < 0.01), and an increasing net amount of hip center medialization (OR 2.76 [95% CI 1.70 to 4.47]; p < 0.01) were associated with postoperative ischiofemoral impingement in patients with DDH who underwent PAO (R 2 = 0.73). The cutoff values of neck-shaft angle was 138.4°. The cutoff values of the net amount of hip center medialization was 1.9 mm.

CONCLUSIONS

Postoperative ischiofemoral impingement could occur in patients with acetabular dysplasia who have undergone PAO after hip center medialization. An increasing neck-shaft angle, a positive coxa profunda sign on preoperative imaging, and excessive medialization of the hip center are factors associated with ischiofemoral impingement development in these patients. Therefore, we suggest that physicians measure the ischiofemoral space on a preoperative CT when patients with DDH have an increasing neck-shaft angle (> 138.4°) or a positive coxa profunda sign on radiological imaging. During PAO, the amount of hip center medialization should be carefully controlled to keep these patients from developing postoperative ischiofemoral impingement.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Delayed proximal hamstring tendon repair after ischial tuberosity apophyseal fracture in a professional volleyball athlete: a case report

Background

Ischial tuberosity apophyseal fractures are avulsion fractures of the anatomic footprint of the proximal hamstring tendons. Generally, these injuries are rare and frequently occur in skeletally immature, active patients due to incomplete ossification. Depending on the fragment displacement, non-operative or operative treatment approaches are used.

Case presentation

We report a case of a 29-year-old professional volleyball athlete who has suffered from a nonunion avulsion fracture for 14 years. Isolated suture anchor fixation was performed after open excision of a large bony fragment followed by excellent clinical and functional outcome at 1 year postoperatively.

Conclusion

In conclusion, avulsion fractures of the ischial tuberosity with large fragments and restrictions to activities of daily living due to pain can, in individualized cases, be treated with an open excision of the fragment followed by repair of the proximal hamstring tendons using suture anchors.

Classifying Ischial Tuberosity Avulsion Fractures by Ossification Stage and Tendon Attachment

BACKGROUND

We propose a new classification system for ischial tuberosity fractures in adolescents that is based on the ossification pattern of the apophysis.

METHODS

We performed a retrospective review of patients who were diagnosed with ischial tuberosity avulsion fractures at a single institution from 2008 to 2018. Skeletal maturity and fracture location, size, and displacement were recorded based on initial injury radiographs. The fractures were classified by location as being lateral (type 1) or complete (type 2). Pelvic computed tomography (CT) review demonstrated 5 stages of ossification. We then reviewed pelvic CT and magnetic resonance imaging scans to assess the tendinous insertions at the ischial tuberosity apophysis. Reliability analysis was performed.

RESULTS

We identified 45 ischial tuberosity fractures. The mean patient age was 14.4 years (range, 10.3 to 18.0 years). Boys accounted for 82% of the cohort. Forty-seven percent of the fractures were classified as type 1, and 53% were classified as type 2. Type-1 fractures were associated with younger age (p = 0.001), lower Risser score (p = 0.002), lower modified Oxford score (p = 0.002), less displacement (p = 0.001), and smaller size (p < 0.001) when compared with type-2 fractures. Of the 45 patients, 18 had follow-up of >6 months, with 56% going on to nonunion. Nonunion was associated with greater displacement (p = 0.016) and size (p = 0.027). When comparing union rates by fracture type, 33% of type-1 fractures progressed to nonunion, while 78% percent of type-2 fractures progressed to nonunion; however, this difference was not significant (p = 0.153). A review of the advanced imaging indicated that type-1 fractures involved the semimembranosus and conjoined tendons, whereas type-2 fractures also involved the adductor magnus tendon.

CONCLUSIONS

We propose a new classification system based on the ossification pattern of the ischial tuberosity apophysis that reflects the skeletal maturity of the patient, the size and location of the fracture, and the amount of displacement, and likely predicts the probability of subsequent nonunion. The ischial tuberosity ossifies in a pattern similar to the iliac crest as described by Risser, and this pattern of ossification dictates the size of the ischial tuberosity avulsion fracture fragments and the involved tendons.

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.

Deep gluteal syndrome as a cause of posterior hip pain and sciatica-like pain

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis. After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy. Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve. Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment. Cite this article: Bone Joint J 2020;102-B(5):556-567.

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.

Surgical treatment for acute ischial tuberosity avulsion fracture: A case report

RATIONALE

Ischial tuberosity avulsion fracture (ITAF) is a very rare sports injury, and there is currently no consensus on its diagnosis and treatment. Although conservative treatment is adequate for most patients, those with large displacement of the fracture need surgical management.

PATIENT CONCERNS

A 13-year-old male athlete experienced tearing pain in the right hip during a sprint. Radiographic examination showed an avulsion fracture of the right ischial tuberosity.

DIAGNOSIS

Right ITAF.

INTERVENTIONS

On the 3rd day of injury, the patient was treated with open reduction and internal fixation of ITAF under general anesthesia.

OUTCOMES

The patient received a systematic postoperative exercise in 2 weeks, and the fracture healed 4 weeks later. After 8 months, the patient returned to the field to participate in the competition.

LESSONS

Early surgical treatment can bring about good results in the treatment of ITAF with large displacement. The longitudinal incision and subgluteal approach is an ideal choice for the operative procedure.

Proximal Hamstring Injuries: Management of Tendinopathy and Avulsion Injuries

PURPOSE OF REVIEW

To outline the typical presentation, physical examination, diagnostic imaging, and therapeutic treatment options for proximal hamstring injuries to improve awareness, expedient diagnosis, and definitive management.

RECENT FINDINGS

Proximal hamstring tendinopathy and partial-thickness tears can often successfully be managed with a combination of non-operative modalities, including physiotherapy focused on eccentric strengthening, extracorporeal shock wave therapy, or peri-tendinous injections. Surgery is reserved for refractory cases, but can yield good outcomes. Contrastingly, non-operative treatment often leads to unsatisfactory outcomes in complete ruptures, with residual weakness and reduced function with poor return-to-sport rates. Instead, surgical repair can provide satisfactory outcomes, with good-to-excellent functional outcomes and strength, with acute treatment preferred over delayed, chronic repair. Hamstring tendinopathy and partial-thickness tears can be successfully treated non-operatively with good functional outcomes, with surgical repair reserved for refractory cases. Complete tears are best managed with surgical repair, allowing improved strength and functional outcomes.

Avulsion Fractures of the Ischial Tuberosity: Progress of Injury, Mechanism, Clinical Manifestations, Imaging Examination, Diagnosis and Differential Diagnosis and Treatment

Avulsion fracture of the ischial tuberosity (AFIT) is a rare adolescent sports injury. At present, there is no consensus on its therapeutic paradigm, but conservative treatment appears to be the predominate choice. Furthermore, the degree of fracture displacement (DFD) remains as an important factor in determining whether AFIT needs internal fixation. The aim of the present study was to review and update the injury mechanism, clinical manifestations, imaging examination, diagnosis and differential diagnosis, and treatment of AFIT.

A literature search was performed on a variety of databases using text words, and the results were limited to the English language.

This review provides an important reference for the diagnosis and treatment of AFIT.

AFIT can be easily misdiagnosed. Therefore, a detailed medical history and imaging examination are crucial for a correct diagnosis and differential diagnosis. For the choice of treatment of AFIT, it is necessary to consider not only the size of the fracture and DFD, but also the long-term functional needs of the patient.

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.

Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

OBJECTIVE

The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions.

DESIGN

The study employed a prospective design.

SETTING

Sports medicine center within a tertiary care institution.

PARTICIPANTS

Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study.

METHODS

An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image.

MAIN OUTCOME MEASUREMENTS

The main outcome measurements were the IFS dimensions acquired with MRI.

RESULTS

The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t₁₉ = 3.911, p = .001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t₁₉ = 12.716, p < .001).

CONCLUSIONS

Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and supine versus prone positions. This finding has implications when evaluating for ischiofemoral impingement, an entity resulting in hip and/or buttock pain secondary to impingement of the quadratus femoris muscle within a pathologically narrowed IFS. One will need to account for patient hip flexion and supine versus prone positioning when evaluating individuals with suspected ischiofemoral impingement.