Complications of hip preserving surgery

Terminologia Anatomica 2nd edition: perspectives from anatomy educators in the United Kingdom

English anatomical terminology has evolved over the long history of anatomical practice, with major influences from ancient Greek, classical Latin, Arabic, and post-classical Latin. Beginning in the nineteenth century, there have been various attempts to standardise and rationalise anatomical language, beginning in 1887, and culminating in the publication in 2019 of the second edition of the Terminologia Anatomica. This paper presents a brief historical overview of the development of anatomical terminology and usage in English, followed by a summary of the results of an anonymised survey of current practices that was sent out by email to anatomy educators at 45 medical schools in the United Kingdom. This is followed by personal reflections by six senior academics and/or clinicians, reviewing their extensive experience of teaching, researching, and communicating the language of anatomy within United Kingdom medical and clinical institutions.

Femoro-Epiphyseal Acetabular Roof Index Values on Anteroposterior Pelvic Radiographs Significantly Increase With Hip Adduction and Decrease With Abduction

PURPOSE

To investigate the impact of hip adduction and abduction on the femoro-epiphyseal acetabular roof (FEAR) index using conventional anteroposterior pelvic radiographs of patients with borderline hip dysplasia (BHD).

METHODS

Patients with BHD (lateral center edge angle [LCEA] with values of 18° ≤ LCEA <25°) and who were subject to periacetabular osteotoym were selected from a consecutive retrospective cohort from January 2009 to January 2016. The hip ad-/abduction (adduction handled as negative values) and the FEAR index (lateral opening angles handled as positive values) were measured in the initially standardized acquired pelvic radiographs. Thereafter, using surgical planning software, different degrees of hip adduction and abduction were simulated from 20° of adduction to 30° of abduction, and the FEAR index was measured at each position. Pearson correlation was used to identify a potential correlation between the hip ad-/abduction and the FEAR index.

RESULTS

Eighty-nine hips were included. Initial radiographs showed unintentional mean ad-/abduction of -5.3° ± 3.1° (range, -14° to 2°). The mean FEAR index at the initial ad-/abduction angle was -3.6° ± 7.2° (range, -18.0° to 16.0°) and was significantly different from neutral position (0° of ad-/abduction) -9.2° ± 7.0° (range, -27.0° to 10.0°) (P < .001). The FEAR index was negatively correlated to the hip ad-/abduction angle (r = 1, P < .001), with lower values for the FEAR index with the hip in abduction.

CONCLUSIONS

Significant differences in FEAR index measurements were observed depending on hip ad-/abduction on pelvic radiographs. A linear change of the FEAR index of 5° per 5° of hip adduction or abduction could be demonstrated, with adduction resulting in increasing and abduction in decreasing values for the FEAR index.

LEVEL OF EVIDENCE

Level III, diagnostic study.

A comprehensive review of hip arthroscopy techniques and outcomes

Transforming the orthopedic landscape, hip arthroscopy pioneers a minimally invasive surgical approach for diagnosing and addressing hip pathologies. With its origins dating back to Burman's 1931 cadaveric study, this groundbreaking technique gained clinical relevance in 1939 through Takagi's report. However, the 1980s marked the actual emergence of hip arthroscopy for treating a wide range of hip disorders. Now, a staple in modern orthopedics, hip arthroscopy empowers patients with previously undiagnosed and untreated hip conditions, enabling them to obtain relief and reclaim their lives. By employing a compact camera and specialized tools, surgeons expertly navigate the hip joint, performing procedures from excising loose bodies and mending labral tears to addressing femoroacetabular impingement and tackling other intricate issues. This innovative approach has dramatically elevated patients' quality of life, allowing them to embrace targeted treatments and resume daily activities without resorting to lifestyle alterations.

Incidence of Venous Thromboembolism After Hip Arthroscopy Is Low With or Without Prophylaxis but Risk Factors Include Oral Contraceptive Use, Obesity, and Malignancy

PURPOSE

To determine the incidence of and risk factors for symptomatic venous thromboembolism (VTE) after hip arthroscopy (HA) and thromboprophylaxis prescription utilization for this procedure.

METHODS

The PearlDiver Mariner database was queried using Current Procedural Terminology codes to identify adult patients (aged ≥ 18 years) who underwent HA between 2010 and 2020. Patient demographic information, including age, oral contraceptive use, and medical comorbidities, as well as perioperative thromboprophylaxis utilization, was recorded using International Classification of Diseases codes and National Drug Codes. The incidence of postoperative VTE within 90 days was determined. Multivariate logistic regression was used to identify predictors of perioperative thromboprophylaxis utilization and risk factors for VTE.

RESULTS

The queried records identified 60,181 patients who met the inclusion criteria. Of these patients, 367 (0.6%) experienced VTE, including deep venous thrombosis (0.5%) and/or pulmonary embolism (0.2%). Approximately 2.1% of patients used thromboprophylaxis, including aspirin (1.1%), low-molecular-weight heparin (0.9%), and oral factor Xa inhibitors (0.1%). Oral contraceptive pill use (adjusted odds ratio [aOR], 2.16; 95% confidence interval [CI], 1.34-3.46), obesity (aOR, 1.37; 95% CI, 1.05-1.79), and a history of malignancy (aOR, 1.69; 95% CI, 1.12-2.54) were associated with increased odds of experiencing VTE. Perioperative thromboprophylaxis (aOR, 0.52; 95% CI, 0.19-1.39) was not significantly associated with decreased odds of experiencing VTE. However, obesity (aOR, 1.17; 95% CI, 1.00-1.38) and hypertension (aOR, 1.17; 95% CI, 1.02-1.36) were associated with increased odds of thromboprophylaxis prescription utilization.

CONCLUSIONS

Although the overall risk of symptomatic VTE after HA remains low, oral contraceptive use, obesity, and a history of malignancy are associated with increased odds of thromboembolic events within 90 days. Routine thromboprophylaxis after HA may not be indicated in all patients but can be considered based on patient-specific risk factors.

LEVEL OF EVIDENCE

Level III, retrospective prognostic comparative trial.

Sonography-Based Determination of Hip Joint Anterior Alpha-Angle: A Reliable and Reproducible Method

PURPOSE

Femoroacetabular impingement (FAI) is a known risk factor for hip osteoarthritis. The gold standard for diagnostics is X-ray and MRI. The accuracy of hip joint alpha angle measurements obtained using sonography is equal to measurements in MRI for patients with cam impingement of the hip joint.

MATERIALS AND METHODS

Patients with hip pain and MRI and sonography were evaluated between January 2015 and December 2019 in a single center. Musculoskeletal sonography was performed according to the DEGUM guidelines by ultrasound-certified specialists. Measurements were repeated three times by two independent investigators.

RESULTS

285 patients were screened, and 110 patients (49 females, 61 males) met the inclusion criteria. The mean age at time of investigation of 54 left and 56 right hip joints was 54.2 years. 1320 measurements were performed. The mean alpha angle was 50.7° in MRI and 50.4° in sonography with a mean difference of 0.28° (p>0.05).

CONCLUSION

Determining hip alpha angle using sonography is a safe and reproducible method. No statistically significant differences between results in MRI and sonography could be seen. Although this is a retrospective, single-center study including only Caucasian mid-Europeans and with the known limitations of ultrasound imaging, it nevertheless shows that sonography can be used as a simple, cheap, and fast technique to assess the hip alpha angle without losing diagnostic quality.

What is the agreement between intraoperative fluoroscopy and postoperative radiographs in Bernese periacetabular osteotomy?

BACKGROUND

It is important to reorient the acetabular fragment into an optimal position and version to ensure a good long-term outcome after Bernese periacetabular osteotomy (PAO). Unfortunately, the intraoperative balance between overcorrection and undercorrection remains challenging for the surgeon. The purpose of this study was to answer two questions: (1) Does the femoral head coverage measured on intraoperative fluoroscopy agree with that measured on postoperative radiography? (2) What is the reliability of intraoperative fluoroscopy in identifying hip center correction in PAO?

METHODS

A total of 173 patients (173 hips) who underwent PAO for developmental dysplasia of the hip (DDH) at our center from July 01, 2020, to December 31, 2020, were retrospectively reviewed. Imaging data from 111 patients (female/male, 98/13; right/left, 72/39; mean age, 28.93 years) were included in this study. The analysis included measurement of the lateral center-edge angle (LCEA), acetabular index (AI), anterior wall index (AWI), posterior wall index (PWI), extrusion index (EI), and medial offset distance (MO). These measurements were acquired from intraoperative fluoroscopic images and postoperative radiographs and compared by paired t test using SPSS (version 24.0). Significance was determined at a p value of < 0.05. Bland-Altman analysis, conducted using GraphPad Software (version 9), was used to quantify the agreement between intraoperative fluoroscopic images and postoperative radiographs.

RESULTS

The means (standard deviations, SDs) of the LCEA, AI, AWI, PWI, EI, and MO obtained on intraoperative fluoroscopy were 32.86° (5.73°), 0.66° (5.55), 0.29 (0.10), 0.75 (0.17), 11.15% (6.50%), and 8.49 mm (3.68 mm), respectively. On postoperative radiography, the corresponding values were 32.91° (6.31°), 1.63° (5.22°), 0.29 (0.15), 0.85 (0.14), 11.27% (7.36%), and 9.60 mm (3.79 mm). The differences in the LCEA, AWI, and EI acquired from intraoperative fluoroscopic images and postoperative radiographs were not significant (p = 0.90, 0.95, and 0.83, respectively), but those in the AI, PWI, and MO were significant (p < 0.05). The mean biases (95% limits of agreement) of the LCEA, AI, AWI, PWI, EI, and MO were - 0.04 (- 6.85), - 0.97 (- 7.78), 0 (- 0.30), - 0.11 (- 0.36), - 0.12 (- 11.92), and - 1.11 (- 5.51), respectively.

CONCLUSION

The LCEA, EI, and AWI can be used to reliably predict postoperative femoral head coverage at the level of 2D graphics. Acetabular inclination can be cautiously assessed using AI on intraoperative fluoroscopy. In the absence of intraoperative 3D image evaluation, the AWI and PWI demonstrate acceptable agreement between fluoroscopy and radiography in assessing the acetabular version. Although the MO shows slight bias, it can be helpful in properly positioning the acetabulum during PAO.

The traction force of the pulled limb in hip arthroscopic surgery is determined by stiffness coefficient which is significantly related to muscle volume

PURPOSE

To verify the relationship between muscle volume, lateral centre-edge angle (LCEA), alpha angle (AA), body mass index (BMI) and Beighton score with stiffness coefficient (SC). To analyse the difference of traction force at different physical states of hip joint capsule.

METHODS

Thirty-six patients who underwent hip arthroscopy operation were included. The volumes of some related muscles were measured in MRI images by 3D Slicer. We recorded and tested differences in traction force of five joint capsule physical states, including before (State 1) and after joint capsule puncture (State 2), after the establishment of anterolateral and mid-anterior approaches (State 3) and after incision of the joint capsule through these two approaches (States 4, 5). The correlation between muscle volume, BMI, LCEA, AA and SC was verified by Spearman test. Poisson regression was used to explain confounding variables.

RESULTS

The average force at State 1 was 531.8 N. There were significant differences in traction force between these five states (p < 0.001). There was a significant positive correlation between muscle volumes and SC (p < 0.001). BMI had no correlation with SC (n.s.). The preoperative LCEA of the affected side was correlated with SC (p = 0.043). AA and SC were not correlated (n.s.).

CONCLUSION

The physical states of the hip joint capsule affected traction force. Muscle volume rather than BMI is an ideal index to estimate preoperative traction force. LCEA affected traction force, whilst AA and Beighton score did not. Measuring the muscle volume can help estimate the most suitable traction force for the patient.

LEVELS OF EVIDENCE

IV.

[Persistent or recurrent symptoms after surgery for femoroacetabular impingement syndrome (FAIS) : Pathology, diagnostics and therapy]

BACKGROUND

Femoroacetabular impingement syndrome (FAIS) has gained vast importance in the last two decades. Multiple studies have shown that if untreated, early osteoarthritis of the hip joint may result. Hip arthroscopy is one of the fastest growing procedures in the orthopedic cosmos, having already replaced the majority of (mini) open techniques in FAIS surgery. However, with the recent remarkable increase in the volume of hip arthroscopies performed worldwide, the number of patients with persistent or recurrent symptoms after FAIS surgery is also growing.

PATHOLOGY

Potential underlying pathologies are misresection of the bony deformity, insufficiency fracture of the femoral head neck junction or the femoral subchondral head itself (SIFFH), adhesions, failed chondrolabral or capsular treatment, septic arthritis, heterotopic ossification or a wrong indication in the case of osteoarthritis that is already too advanced. Most of these occur more often during the extensive learning curve for hip arthroscopy.

DIAGNOSTICS

High-quality imaging plays a key role in determining the need for revision surgery vs. further conservative treatment. Therapeutical avenues are shown with the common goal of proper detection and correction of the underlying pathology to address unsatisfactory FAIS treatment outcomes and ensure long-term survival of the native hip joint.

Editorial Commentary: The Measurement of the Alpha Angle in Femoroacetabular Impingement Syndrome With a 45° Dunn-View Radiograph Predicts the Cartilage Damage on the Acetabular Side of the Hip Joint-Is It as Simple as That?

In recent years, femoroacetabular impingement syndrome (FAIS) has developed itself into a well-known pathology throughout the orthopaedic community worldwide. The more we learned, the more sophisticated it became: In the beginning, we measured the femoral head-neck offset; then, the alpha angle was found to be a useful measurement in detecting FAIS. We learned to perform these measurements with, for example, the 45° Dunn view. The alpha angle, but not the femoral head-neck offset, measured as described, predicts not only the acetabular cartilage damage resulting from FAIS but also the correlation between the degree of the alpha angle and the severity of the cartilage damage within the acetabular labrum articular disruption and Outerbridge classifications. The femoral head-neck offset cannot provide us with this information, but it is the first sign we all look at before taking any measurements on radiographs or magnetic resonance imaging scans if a cam morphology could be present. It is paramount to understand the underlying problems of the individual hip and distinguish instability (dysplasia) from FAIS and also to evaluate femoral torsional abnormalities to perform the appropriate treatment using magnetic resonance imaging and computed tomography scans if necessary. The alpha angle quantifies the severity of the pathology and predicts the possible cartilage damage in FAIS patients, but in our opinion, we cannot neglect the femoral head-neck offset, because it is often the first radiologic sign of FAIS that most of us realize on a radiograph. Therefore, both signs have their place in detecting and treating FAIS.

[Recent research progress of hip-preserving treatment for adolescents and adults with developmental dysplasia of the hip]

Objective

To review the imaging evaluation, treatment progress, and controversy related to developmental dysplasia of the hip (DDH) in adolescents and adults.

Methods

The domestic and abroad hot issues related to adolescents and adults with DDH in recent years, including new imaging techniques for assessing cartilage, controversies over the diagnosis and treatment of borderline DDH (BDDH), and the improvement and prospect of peracetabular osteotomy (PAO) were summarized and analyzed.

Results

DDH is one of the main factors leading to hip osteoarthritis. As the understanding of the pathological changes of DDH continues to deepen, the use of delayed gadolinium-enhanced MRI of cartilage can further evaluate the progress of osteoarthritis and predict the prognosis after hip preservation. There are still controversies about the diagnosis and treatment of BDDH. At the same time, PAO technology and concepts are still being improved.

Conclusion

Cartilage injury and bony structure determine the choice of surgical methods and postoperative prognosis of hip preservation surgery. The hip preservation of adolescent and adult DDH patients will move towards the goal of individualization and accuracy.

High prevalence of hip lesions secondary to arthroscopic over- or undercorrection of femoroacetabular impingement in patients with postoperative pain

Objectives

To compare the prevalence of pre- and postoperative osseous deformities and intra-articular lesions in patients with persistent pain following arthroscopic femoroacetabular impingement (FAI) correction and to identify imaging findings associated with progressive cartilage damage.

Methods

Retrospective study evaluating patients with hip pain following arthroscopic FAI correction between 2010 and 2018. Pre- and postoperative imaging studies were analyzed independently by two blinded readers for osseous deformities (cam-deformity, hip dysplasia, acetabular overcoverage, femoral torsion) and intra-articular lesions (chondro-labral damage, capsular lesions). Prevalence of osseous deformities and intra-articular lesions was compared with paired t-tests/McNemar tests for continuous/dichotomous data. Association between imaging findings and progressive cartilage damage was assessed with logistic regression.

Results

Forty-six patients (mean age 29 ± 10 years; 30 female) were included. Postoperatively, 74% (34/46) of patients had any osseous deformity including 48% (22/46) acetabular and femoral deformities. Ninety-six percent (44/46) had an intra-articular lesion ranging from 20% (9/46) for femoral to 65% (30/46) for acetabular cartilage lesions. Prevalence of hip dysplasia increased (2 to 20%, p = 0.01) from pre- to postoperatively while prevalence of cam-deformity decreased (83 to 28%, p < 0.001).

Progressive cartilage damage was detected in 37% (17/46) of patients and was associated with extensive preoperative cartilage damage > 2 h, i.e., > 60° (OR 7.72; p = 0.02) and an incremental increase in postoperative alpha angles (OR 1.18; p = 0.04).

Conclusion

Prevalence of osseous deformities secondary to over- or undercorrrection was high. Extensive preoperative cartilage damage and higher postoperative alpha angles increase the risk for progressive degeneration.

Key Points

• The majority of patients presented with osseous deformities of the acetabulum or femur (74%) and with intra-articular lesions (96%) on postoperative imaging.

• Prevalence of hip dysplasia increased (2 to 20%, p = 0.01) from pre- to postoperatively while prevalence of a cam deformity decreased (83 to 28%, p < 0.001).

• Progressive cartilage damage was present in 37% of patients and was associated with extensive preoperative cartilage damage > 2 h (OR 7.72; p = 0.02) and with an incremental increase in postoperative alpha angles (OR 1.18; p = 0.04).

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08398-4.