Iranian Journal of Orthopedic Surgery

Abstract Background: Severe acetabular bone loss following total hip arthroplasty (THA) presents a complex reconstructive challenge. Traditional classification systems, such as Paprosky, may not fully capture the morphology of defects in the most extreme cases. Additionally, previous revision plans could not safely manage such cases.
Case Presentation: A 71-year-old man presented with pain and instability four years after a primary THA. Imaging revealed a massive acetabular defect with extensive osteolysis and metallosis, including complete loss of the posterior column, medial wall, posterior wall, inferior rim, and ischium, and only the anterior wall and column remained intact. The acetabular cup had also protruded into the pelvic cavity, approaching the bladder, and had migrated centrally. While the defect resembled a Paprosky type IIC pattern, it was markedly more severe and did not fit existing classifications. A complex two-stage reconstructive surgery was performed, involving elevation of the hip center by 2.5 to 3 cm and compensation for limb shortening through femoral stem lengthening using a long-stem prosthesis. After 2-step revision surgery, the patient experienced prosthetic dislocation, necessitating a third surgery. During this procedure, a bipolar cup was manually drilled to allow bone cement to pass through the holes for improved fixation. Additionally, bone cement was applied over the screw heads (positioned superior to the cup) to construct a scaffold that enhanced implant stability and reduced the risk of dislocation.
Discussion: This case may represent a novel subtype of acetabular bone defect not encompassed by current classification systems. Furthermore, the innovative approach of penetrating a bipolar cup and using cement augmentation over a screw framework presents a potential new strategy for achieving stable fixation in cases of severe bone loss.
Conclusion: This case underscores the need for updated classification systems to account for atypical acetabular defect patterns and demonstrates a novel fixation technique that may improve outcomes in revision THA involving extensive bone loss.
 

Abstract Introduction: Hip dysplasia can be associated with early degenerative changes. Different values have been reported for incidence of hip dysplasia in different countries. In the current study, we are reporting on the incidence of hip dysplasia in a group of normal Iranians evaluated by measuring the morphologic parameters of acetabulum on radiographs. Materials and Method: 586 hips (293 person) were enrolled in this study. On anteroposterior hip radiographs, the following 5 parameters were measured: Central edge angle (CEA), acetabular angle (AA), acetabular depth (AD), acetabular roof obliquity (ARO) and roof angle (RA). The normal and abnormal values were obtained in different sexes and compared with the known normal values in orthopaedic literature. Furthermore, the correlation between the above measurements was investigated. Results: Based on CEA, 15 (2.6%) of hips were dysplastic:-0.7% definite and 1.9% mild. 19 hips (3.2%) were dysplastic when using AA values. AD and RA were significantly higher in males. Except for lack of correlation between AA and AD, the other parameters -in particular, CEA and AA- were closely correlated. CEA, AA, ARO and RA were significantly different between dysplastic and non-dysplastic hips. Conclusion: Definite or mild dysplasia was recognized in 0.7% and 1.9% of the “normal” population that was studied. Since CEA was the same between males and females and was correlated with all other morphologic parameters, it seems that CEA is a useful measurement to evaluate presence of hip dysplasia.

Abstract Background: The knowledge about acetabular version and angle changes in different conditions is important. The normal acetabular version may be different in various populations. We would like to report measurement of this value in a small sample of Iranains with non-orthopaedic conditions. Methods: One coronal pelvic CT film of 81 patients (54 male, 27 female) who had undergone CT scanning for non-orthopaedic reasons was examined in a retrospective cross-sectional study. The acetabular versions were measured and compared for different genders and different age decades. The patients were aged 41.5±14.1 years. Results: The acetabular version was 17.7±3.4 degrees (range: 8 to 32 degrees). There was no significant relationship between acetabular version and age or gender in this sample. Conclusions: The acetabular version in this Iranian group ranged from 17.4 to 19.4 degrees with 95% confidential intervals.

Abstract Background: The posterior of acetabular cup in total hip replacement can be affected by the central osteophytes in the acetabular fovea. We are proposing a classification of such osteophytes based on direct observation and CT scan of osteoarthritis hips.Methods: This study was composed of two sections: first, 276 cases with all clinical and radiographic evidence of osteoarthritis of hip–with no history of fracture or pelvic bony surgery – were studied by radiographs and CT Scans. The changes in the acetabular osteophytes were evaluated and categorized. Secondly, 57 cases of hip osteoarthirites who were undergoing hip arthroplasty received direct observation of the acetabular osteophytes and categorization of the acetabular fovea in accordance with the above classification system. The relation of primary etiology of hip osteoarthritis with the osteophyte classification was also studied.Results: According to radiographs, CT Scans and direct visualization, four types of acetabular osteophytes were identified. Type I: Normal acetabular with 5mm distance from rim to the floor type IIa: Evidence of sclerosis around fovea type IIb: Sclerosis forming a ceiling, like an umbrella over the fovea type IIc: The foveal osteophytes are almost touching in the center type III: Osteophytes have fully covered the fovea, making the acetubular look very shallow.Conclusion: Study and categorization of acetabular osteophytes with radiographs and CT scan would be a helpful pre-operative tool for more accurate reaming of the acetabular cavity and cup positioning in hip osteoarthrties.

Abstract Background: Unstable pelvic fractures are major orthopaedic injuries with high rates of morbidity and mortality. Open surgical stabilization is the standard treatment for a great number of them. Percutaneous surgical fixation has become an accepted treatment method in last several years. We would like to report our experience with this relatively, newer technique in a small mixed group of unstable pelvic ring fractures.Methods: This is a report of 16 cases (13 males, 3 females) with mean age of 31±8 years of pelvic and acetabular fractures who received percutaneous iliosacral or iliopubic screw fixation, under C-arm imaging control, and had a 6 months period of clinical and radiographic follow-up.Results: All 16 cases had healed their fractures at follow-up and had full weight-bearing status. 12 cases returned to their pre-fracture activities. One screw break and one wound infection were the complications list. There was no neurological deficit, and average blood loss was 10 milliliters.Conclusion: Percutaneous iliosacral or iliopubic screw fixation for, respectively, posterior pelvic ring or anterior column acetabular injuries are useful surgical treatment options with low complication rates.

Abstract Background: Acetabular fracture is usually due to severe trauma and it is often accompanied with other comorbidities.  Most often the treatment of choice is open reduction and internal fixation. There are early and late complications of surgical treatment. In this study we tried to investigate early complications including nerve injury, infection, heterotopic ossification and thromboembolism among our patients.Methods: In this prospective descriptive epidemiologic study, 46 patients (39 men, 7 women) with the mean age of 34.3 years old (range of 17–71 years) who had undergone open reduction and internal fixation of acetabular fracture in a 3 year period in two teaching hospitals in Ahwaz were studied for their early complications. The follow ups had a range of 3 to 35 months (mean: 11 months).Results: From 46 patients, 34 had type A and 12 type B acetabular fractures (based on AO classification).  There were 5 cases (10.9%) of iatrogenic peroneal nerve injury, 6 (13%) infection, and 12 (26.1%) heterotopic ossification. There was no case of thromboembolism.Conclusion: Acetabular fracture fixation is generally associated with high complication rate. Our cases had unexpectedly, more complications in comparsion to similar reports.

Abstract Background: Dislocation of total hip arthroplasty may happen for different reasons. Abnormal acetabular orientation is a common reason for such occurance. We would like to report the effect of acetabular inclination on incidence of dislocation.Methods: In a cross-sectional study all cases of total hip arthroplasty performed in a 2-yaer interval in one educational hospital in Tehran, were followed and assessed for possible dislocation in a 18.1 months (3-25 months) of follow-up. The inclination angles of acetabular components were measured, and the relationship of dislocation with gender, age and this angle was evaluated.Results: 132 cases entered the study. 4 patients (3%) encountered dislocation and all 4 had inclination angles of over 50 degrees. Gerder did not seem to play an important role. Older age, however, was probably contributing to risk of dislocation.Conclusion: Inclination angle of over 50 degree in acetabular component position is one of the factors making it more likely for the hip arthroplasty to dislocate.

Abstract Background: Acetabular fracture is a common injury, with unclear treatment outcome. We are reporting the results of treatment of unstable acetabular fractures, comparing operative with non-operative treatment in a small group of patients.Methods: In a retrospective study, in a teaching hospital, 20 cases of unstable acetabular fracture treated with open reduction and internal fixation were compared with 20 cases who had been treated non-surgically. The mean age was 34.5 years old (20-50 yrs old). The early clinical resuts, including complications, and also treatment costs were compared in those two groups.Results: There was no significant difference in the level of function between the two groups.There was a higher rate of heterotopic ossification and nerve injury in the operated cases, but not statistically significant. The time to fracture :::union::: was less in the non-operated cases. The hospital cost was significantly higher in the non-operative group (p < /em>

Abstract Background: Fracture dislocation of the hip is a result of high energy trauma and can lead to hip dysfunction and patient disability. Stable and perfect reduction of the femoral head and acetabular wall are the two most important prognostic factors. The aim of this study was to compare the results of surgical treatment with nonsurgical treatment in this injury.Methods: In a period of 2 years, the cases of posterior hip dislocation with acetabular rim fracture were studied. Two groups were recognized after closed reduction of dislocation. First group (18 patients) received open reduction and plating of acetabular fracture followed by 3-5 weeks of skeletal traction. The second group (14 patients) was treated by skeletal traction of 5-6 weeks. The patients were evaluated for hip motion, stability, complications or nerve injury and early osteoarthritis, and acetabular fracture index in average one year follow-up. The results were compared in the two groups.Results: Restriction of hip motion was more common in nonsurgical patients. Sciatic nerve injury was noted in 3 patients of surgical group with recovery in 2 of them. Perfect reduction was seen in 17 (94.4%) of surgical and 9 (64.3%) of nonsurgical patients. Primary osteoarthritis was seen in 7 patients (38.9%) of surgical and 8 patients (57%) of nonsurgical group. AFI in surgical and nonsurgical groups were 55.2% and 32.5% respectively. Surgical patients had better functional results.Conclusion: Articular damage by initial trauma, perfect reduction of the hip and stable anatomic fixation of the acetabular wall are the important prognostic factors. The patients with surgical treatment obtain better functional outcome.