Surgical Technique: Reverse Periacetabular Osteotomy

Albers, Christoph E.; Steppacher, Simon D.; Tannast, Moritz; Siebenrock, Klaus A.

doi:10.1007/978-1-4614-6965-0_116

Cited by 4 publications

(5 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although none of the subjects in our study had Legg–Calvé–Perthes disease, each presented with loss of femoral head sphericity and head‐neck offset. Also, three of the five subjects received a secondary radiographic diagnosis of cam‐type FAI, which is not uncommon in hips with acetabular retroversion . Rotation of an aspherical femoral head made the hip less congruent, which in‐turn induced areas of focal loading as evidenced by qualitative inspection of the contact stress plots as well as statistically significant changes in contact stress and contact area.…”

Section: Discussionmentioning

confidence: 99%

Changes in chondrolabral mechanics, coverage, and congruency following peri‐acetabular osteotomy for treatment of acetabular retroversion: A patient‐specific finite element study

Knight

Abraham

Peters

et al. 2017

Journal Orthopaedic Research

View full text Add to dashboard Cite

Using a validated finite element (FE) protocol, we quantified cartilage and labrum mechanics, congruency, and femoral coverage in five male patients before and after they were treated for acetabular retroversion with peri-acetabular osteotomy (PAO). Three-dimensional models of bone, cartilage, and labrum were generated from computed tomography (CT) arthrography images, acquired before and after PAO. Walking, stair-ascent, stair-descent, and rising from a chair were simulated. Cartilage and labrum contact stress, contact area, and femoral coverage were calculated overall and regionally. Mean congruency (average of local congruency values for FE nodes in contact) and peak congruency (most incongruent node in contact) were calculated overall and regionally. Load supported by the labrum was represented as a raw change in the ratio of the applied force transferred through the labrum and percent change following surgery (calculated overall only). Considering all activities, following PAO, mean acetabular cartilage contact stress increased medially, superiorly and posteriorly; peak stress increased medially and posteriorly. Peak labrum stresses decreased overall and superiorly. Acetabular contact area decreased overall and laterally, and increased medially. Labral contact area decreased overall, but not regionally. Load to the labrum decreased. Femoral head coverage increased overall, anterolaterally, and posterolaterally, but decreased anteromedially. Mean congruency indicated the hip became less congruent overall, anteriorly, and posteriorly; peak congruency indicated a less congruent joint posteriorly. Clinical Relevance Medialization of contact and reductions in labral loading following PAO may prevent osteoarthritis, but this procedure increases cartilage stresses, decreases contact area, and makes the hip less congruent, which may overload cartilage.

show abstract

Section: Discussionmentioning

confidence: 99%

Changes in chondrolabral mechanics, coverage, and congruency following peri‐acetabular osteotomy for treatment of acetabular retroversion: A patient‐specific finite element study

Knight

Abraham

Peters

et al. 2017

Journal Orthopaedic Research

View full text Add to dashboard Cite

show abstract

“…In reverse PAO, the rotation axis depends on the underlying condition. In cases of acetabular retroversion, the correction mainly consists of internal rotation (transverse plane) and extension (sagittal plane) of the fragment 17 .…”

Section: Resultsmentioning

confidence: 99%

“…To reduce the necessary translation and consequently minimize the change in the center of rotation, cutting of the fragment has been proposed. Albers et al mentioned the need to cut off a supra-acetabular wedge, but that might not be enough in reverse PAO with high degrees of fragment rotation 17 . A general analysis of all pelvic bones has not been conducted to date.…”

Section: Discussionmentioning

confidence: 99%

“…Nevertheless, little if any attention has been given to this factor in the literature thus far. Albers et al reported that, during reverse PAO, a small supra-acetabular wedge resection is required to allow sufficient manipulation of the fragment 17 . However, we are not aware of any studies that have analyzed (1) whether the resection of a supra-acetabular wedge is sufficient to achieve the desired correction and (2) how classic or reverse PAO influences the center of rotation and leg length.…”

mentioning

confidence: 99%

See 1 more Smart Citation

A Statistical Shape Model-Based Analysis of Periacetabular Osteotomies

Kriechling

Leoty

Fürnstahl

et al. 2022

Journal of Bone and Joint Surgery

View full text Add to dashboard Cite

Background:Classic and reverse Bernese periacetabular osteotomy (PAO) have been shown to be effective for the treatment of developmental dysplasia of the hip (by classic PAO), severe acetabular retroversion (by reverse PAO), and some protrusio acetabuli (by reverse PAO). Especially in severe cases with higher degrees of correction, a relevant overlap between the osteotomized fragment and the pelvis might occur, leading to necessary fragment translation. The aim of the present study was to analyze the necessary translation as a function of the degree of correction using a statistical mean model of the pelvis according to the technique (classic PAO or reverse PAO).Methods:A mean statistical shape model of the pelvis and 2 extreme models were used to simulate rotation of the osteotomized fragment during a classic or reverse PAO and to calculate rotations from −20° to 20° in the frontal, sagittal, and transverse planes and a combination thereof. The depth and volume of the intersection between the mobilized fragment and the pelvis were calculated, and the minimum translation of the fragment necessary to avoid segment overlap was determined.Results:The maximum intersection distances between the pelvis and the 20° rotated fragment were 6.7 and 15.3 mm for adduction and abduction (frontal plane), 6.4 and 4.5 mm for internal and external rotation (transverse plane), and 27.8 and 9.2 mm for extension and flexion (sagittal plane). The necessary translations for 20° of fragment rotation were 7.0 and 12.8 mm for adduction and abduction (frontal plane), 4.8 and 5.0 mm for internal and external rotation (transverse plane), and 18.5 mm and 8.8 mm for extension and flexion (sagittal plane).Conclusions:Acetabular reorientation with the classic or reverse PAO results in translation of the fragment and in a consequent change in the rotational center. This finding is more pronounced with higher degrees of fragment reorientation in abduction and extension; it becomes especially pronounced in reverse PAO for acetabular retroversion or protrusio acetabuli, and might limit the ability to achieve the intended improvement in overall hip biomechanics.

show abstract

“…The reverse PAO we describe here includes our technique modifications and differs from the previously described anteverting PAO to treat acetabular retroversion [14,15]. Although PAO to correct acetabular retroversion was originally described as an "anteverting PAO," it has also been described as a "reverse PAO," creating some confusion [1,3,11,16]. The anteverting PAO, as originally described, purely anteverts the retroverted acetabulum, without effort to change the lateral or anterior femoral head coverage [10].…”

Section: Introductionmentioning

confidence: 99%

What Are the Early Outcomes of True Reverse Periacetabular Osteotomy for Symptomatic Hip Overcoverage?

Pun

Hosseinzadeh

Dastjerdi

et al. 2020

Clin Orthop Relat Res

View full text Add to dashboard Cite

Background Acetabular overcoverage is associated with pincer-type femoroacetabular impingement (FAI). A subtype of acetabular overcoverage is caused by a deep acetabulum with a negatively tilted acetabular roof, in which acetabular reorientation may be a preferable alternative to rim trimming to uncover the femoral head. We introduced the true reverse periacetabular osteotomy (PAO) in 2003, which in contrast to an anteverting PAO, also flexes and abducts the acetabulum relative to the intact ilium to decrease anterior and lateral femoral head coverage and correct negative tilt of the acetabular roof. To our knowledge, the clinical results of the true reverse PAO have not been evaluated. Questions/purposes For a group of patients who underwent reverse PAO, (1) Do patients undergoing reverse PAO demonstrate short-term improvement in pain, function, and hip ROM, and decreased acetabular coverage, as defined by lateral and anterior center-edge angle and Tönnis angle? (2) Are there identifiable factors associated with success or adverse outcomes of reverse PAO as defined by reoperation, conversion to THA, or poor patient-reported outcome scores? (3) Are there identifiable factors associated with early complications? Methods Between 2003 and 2017, two surgeons carried out 49 reverse PAOs in 37 patients. Twenty-five patients had unilateral reverse PAO and 12 patients had staged, bilateral reverse PAOs. To ensure that each hip was an independent data point for statistical analysis, we chose to include in our series only the first hip in the patients who had bilateral reverse PAOs. During the study period, our general indications for this operation were symptomatic lateral and anterior acetabular overcoverage causing FAI that had failed to respond to previous conservative or surgical treatment. Thirty-seven hips in 37 patients with a median (range) age of 18 years (12 to 41; interquartile range 16 to 21) were included in this retrospective study at a minimum follow-up of 2 years (median 6 years; range 2 to 17). Thirty-four patients completed questionnaires, 24 patients had radiographic evaluation, and 23 patients received hip ROM clinical examination. However, seven patients had not been seen in more than 5 years. The clinical and radiographic parameters of all 37 hips that underwent reverse PAO in 37 patients from a longitudinally maintained institutional database were retrospectively studied preoperatively and postoperatively. Adverse outcomes were considered conversion to THA or a WOMAC pain score greater than 10 at least 2 years postoperatively. Patient-reported outcomes, radiographic measurements, and hip ROM were evaluated preoperatively and at most recent follow-up using a paired t-test or McNemar test, as appropriate. Linear regression analysis was used to assess for identifiable factors associated with clinical outcomes. Logistic regression analysis was used to assess for identifiable factors associated with adverse outcomes and surgical complications. All tests were two-sided, and p values less than 0.05 were considered significant. Results At a minimum of 2 years after reverse PAO, patients experienced improvement in WOMAC pain (-7 [95% CI -9 to -5]; p < 0.001), stiffness (-2 [95% CI -3 to -1]; p < 0.001), and function scores (-18 [95% CI -24 to -12]; p < 0.001) and modified Harris Hip Score (mHHS) (20 [95% CI 13 to 27]; p < 0.001). The mean postoperative hip ROM improved in internal rotation (8° [95% CI 2° to 14°]; p = 0.007). Acetabular coverage, as defined by lateral center-edge angle (LCEA), anterior center-edge angle (ACEA), and Tönnis angle, improved by -8° (95% CI -12° to -5°; p < 0.001) for LCEA, -12° (95% CI -15° to -9°; p < 0.001) for ACEA, and 9° (95% CI 6° to 13°; p < 0.001) for Tönnis angle. The postoperative severity of radiographic arthritis was associated with worse WOMAC function scores such that for each postoperative Tönnis grade, WOMAC function score increased by 12 points (95% CI 2 to 22; p = 0.03). A greater postoperative Tönnis grade was also correlated with worse mHHS, with an average decrease of 12 points (95% CI -20 to -4; p = 0.008) in mHHS for each additional Tönnis grade. Presence of a positive postoperative anterior impingement test was associated with a decrease in mHHS score at follow-up, with an average 23-point decrease in mHHS (95% CI -34 to -12; p = 0.001). Nineteen percent (7 of 37) of hips had surgery-related complications. Four hips experienced adverse outcomes at final follow-up, with two patients undergoing subsequent THA and two with a WOMAC pain score greater than 10. We found no factors associated with complications or adverse outcomes. Conclusion The early clinical and radiographic results of true reverse PAO compare favorably to other surgical treatments for pincer FAI, suggesting that reverse PAO is a promising treatment for cases of pincer FAI caused by global acetabular overcoverage. However, it is a technically complex procedure that requires substantial training and preparation by a surgeon who is already familiar with standard PAO, and it must be carefully presented to patients with discussion of the potential risks and benefits. Future studies are needed to further refine the indications and to determine the long-term outcomes of reverse PAO. Level of Evidence Level IV, therapeutic study.

show abstract

Surgical Technique: Reverse Periacetabular Osteotomy

Cited by 4 publications

References 29 publications

Changes in chondrolabral mechanics, coverage, and congruency following peri‐acetabular osteotomy for treatment of acetabular retroversion: A patient‐specific finite element study

Changes in chondrolabral mechanics, coverage, and congruency following peri‐acetabular osteotomy for treatment of acetabular retroversion: A patient‐specific finite element study

A Statistical Shape Model-Based Analysis of Periacetabular Osteotomies

What Are the Early Outcomes of True Reverse Periacetabular Osteotomy for Symptomatic Hip Overcoverage?

Contact Info

Product

Resources

About