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Year : 2022  |  Volume : 1  |  Issue : 1  |  Page : 37-42

Sequential bilateral total hip arthroplasty for osseous ankylosed hips with severe flexion deformity in a teenage girl – A case report and review of literature

Department of Orthopaedics, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India

Date of Submission21-Dec-2022
Date of Acceptance01-Jan-2023
Date of Web Publication23-Jan-2023

Correspondence Address:
Roop Bhushan Kalia
Department of Orthopaedics, All India Institute of Medical Sciences, Rishikesh, Uttarakhand
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/juoa.juoa_12_22

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Total hip arthroplasty (THA) in an ankylosed hip is a challenging procedure, especially in the presence of severe flexion deformity. The outcome of surgery largely depends on the surgical technique apart from the degree of the change that occurs in the muscles and soft tissues at the hip from long immobilization, and considerable postoperative rehabilitation is necessary. The complications in these cases are also higher than primary THA for nonankylosed hips. We report a case of a young teenage girl with both hips fused in severe flexion deformity. Surgical technique is described in detail, and pertinent literature is reviewed.

Keywords: Ankylosed hip, severe flexion deformity, surgical technique in the ankylosed hip, total hip arthroplasty, young patient

How to cite this article:
Ansari S, Raja BS, Paul S, Kalia RB. Sequential bilateral total hip arthroplasty for osseous ankylosed hips with severe flexion deformity in a teenage girl – A case report and review of literature. J Uttaranchal Orthop Assoc 2022;1:37-42

How to cite this URL:
Ansari S, Raja BS, Paul S, Kalia RB. Sequential bilateral total hip arthroplasty for osseous ankylosed hips with severe flexion deformity in a teenage girl – A case report and review of literature. J Uttaranchal Orthop Assoc [serial online] 2022 [cited 2023 Jun 3];1:37-42. Available from: http://www.juoa.org/text.asp?2022/1/1/37/368386

  Background Top

Ankylosis of the hip is the total loss of movement at the hip joint. Although there is a painless and stable joint, it can be quite disabling in the long term, especially when it occurs in a poor functional position. The reported prevalence of hip disease in ankylosing spondylitis (AS) varies from 19% to 36%, with 47%–90% of patients displaying bilateral hip involvement, and the hip involvement increases the burden of AS and negatively impacts its prognosis.[1] Patients with juvenile-onset AS (age at disease onset <16 years) are at the highest risk of developing severe hip disease and subsequently needing a hip replacement.[2] Factor associated with end-stage hip disease includes early age at onset, disease duration, enthesopathy, arthritis, and severity of axial disease.[3]

Although fusion of the hip joint leads to a stable and painless hip, the loss of hip function and premature degeneration of neighboring joints negatively impair the quality of life over a long period.[4] The majority of these patients are very young and seek treatment for problems related to function, posture, and locomotion rather than pain.[5] Total hip arthroplasty (THA) can relieve pain and recover the range of motion (ROM) of the hip to improve joint function and self-care ability.[6] Although previous studies have reported good clinical and radiological outcomes of THA for these patients, there is no consensus on synchronous or sequential THA for these bilateral osseous ankylosed hip patients.[7],[8] Most of these patients are satisfied by THA due to mobility of the hip joint, posture correction, limb length discrepancy correction, and relieving the overstress in the neighboring joints.

Many difficulties are anticipated in planning and execution of THA in bony ankylosed hip patients, including positioning of the patient for surgery, exposure of surgical area, the ambiguous identification of original joint plane, disuse osteoporosis, weakness of abductor's muscle, pelvic obliquity, and choice of implants.[8],[9],[10]

Various degrees of deformity of the hips have been documented in the literature; nevertheless, few described severe flexion deformity cases.[11] In this study, we report the midterm outcome of a case of an 18-year-old girl with bilateral ankylosed hip and severe flexion deformity of around 90° managed with staged bilateral THA. Bilateral severe flexion deformity of 90° is a relatively uncommon presentation, especially at an age of 18 years. We want to highlight our operative planning and surgical technique to minimize postoperative complications and improve the outcome.

  Case Report Top

A girl in late adolescence presented with a stooped posture due to restricted motion at bilateral hips. Her complaints were back pain, inability to extend her hip, and inability to walk without support and she could not stand erect [Figure 1]. This caused serious limitation of activities of daily living as she was dependent on her family members for daily needs. More than the pain it was the deformity that was a physical as well as a mental barrier for her survival leading to a depressed and meaningless life in her opinion as a young girl, she was hesitant to go out in society and to her school due to her deformed and bent posture. She was a known case of AS and was not taking any medications. She was an in-home ambulator with support.
Figure 1: Clinical photograph of the patient in standing position from the front (a) and side (b) showing the inability of the patient to stand erect without support. Note the gross stooped posture due to flexion deformity at the hip

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Physical examination revealed a severe flexion deformity of bilateral hips (right hip –90° and left hip –85°) causing a stooped posture. The bilateral knee had a normal range of movement. Neurovascular examination of the lower extremity was within normal limits. Her Harris Hip Score (HHS) was 43 at the initial presentation. Initial radiographs revealed bony ankylosis of the bilateral hips [Figure 2]a and [Figure 2]b. Radiographs of the spine showed fairly normal anatomy [Figure 2]c. THA of bilateral hips staged over 3 weeks was recommended.
Figure 2: Radiograph of the pelvis with bilateral hip in AP view showing the ankylosed bilateral hips with a gross flexion deformity suggested by the inlet appearing view of the AP projection (a) and (b) showing the relation of the ankylosed hips and complete femoral anatomy. The spine anatomy was fairly normal as noted in the AP and lateral radiographs (c). AP: Anterior-posterior

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Treatment and surgical technique

A thorough preoperative workup was undertaken including full-length hip radiographs, radiographs of the lumbosacral spine with hips to assess spinopelvic motion, whole-spine radiographs, gait analysis, and all necessary investigations needed as a part of the preanesthetic check-up. A staged approach was opted considering the complexity, surgical time, and blood loss intraoperatively. The preoperative templating radiographs were not possible to obtain due to the extent of the deformity. However, preoperative computed tomography was obtained to determine the femoral canal diameter, acetabular version, acetabular inclination, femoral version, and offsets. The femoral canal was templated to be 8 mm on both sides. The femoral neck was found to be in 15° and 9° of retroversion in the right and left sides, respectively, as referenced from the posterior femoral condyles. The native acetabular anteversion was 8° on the right side and 2° on the left. Therefore, the implant of choice for the femoral side was S-ROM (DePuy Synthes, USA).

A second-generation cephalosporin was administered 30 min before operation. Under general anesthesia with fascia iliaca block, the patient was positioned in a lateral position with the help of side supports in a radiolucent table. The hips were approached by a modified Hardinge approach under all aseptic precautions. The abductor muscles were found to be healthy with a horizontal direction of muscle fibers. After detaching the anterior one-third of gluteus medius and gluteus minimus, the anterior capsule was resected. One of the most challenging parts of the procedure was neck osteotomy of the hip fused in retroversion. The aim was to detect the site of fusion between the femoral head and the acetabulum. An ossified mass of bone was identified near the superolateral acetabulum with no distinction between the femoral head and the acetabulum. An in situ femoral osteotomy was performed at the femoral head-and-neck junction to dislocate the femur along with the intact neck. A neck resection was performed with the help of the guide of S-ROM. Then, the acetabulum was reamed over the remnant of the fused femoral head up to the floor of the acetabulum. After sequential reaming an appropriate size (Size 50), a porous-coated acetabular component (Pinnacle, DePuy Synthes, USA) was implanted. A highly cross-linked polyethylene liner of size 32 mm was press-fitted into the cup. A similar size of acetabular cups and liners were used for both hips and fixed with 2 screws. The femoral preparation was performed after flexion and external rotation of the limb to deliver the proximal femur for easy access. The canal was completely occluded and flexible reamers of femoral interlocking were used and the 8-mm canal opening was achieved after great difficulty.

The canal was reamed up to 9 mm on both sides to find an appropriate canal fit. The proximal reaming was performed up to 14 mm as per the distal diameter in both hips. The calcar reaming was performed till size small in the right hip and till size large in the left hip as per the best fit obtained intraoperatively. However, a linear undisplaced fracture line was noted extending 3 mm beyond the femoral neck while calcar reaming in the right hip. A prophylactic cerclage wire was placed before reaming to the final size to prevent further propagation of the fracture [Figure 3]a. The S-ROM sleeve was impacted in the best possible bone in retroversion to account for the preoperative anatomy. A femoral stem trial was implanted in 30° of anteversion in relation to the sleeve. While performing trial reduction, stability was found satisfactory in the left hip with standard neck length and on the right side with a +3-mm neck length. The combined anteversion was found to be 40° after trialing. Biolox delta ceramic heads of 32-mm size were used in both hips. The hip was closed in layers. A total of 20° of flexion deformity was left after the procedure which was estimated to be corrected automatically with soft tissue compliance.
Figure 3: Intraoperative picture (a) showing modular femoral stem insertion using S-ROM prosthesis (DePuy Synthes, USA) and the anterior femoral cortex crack (black arrow) and wiring to prevent crack progression (red arrow). Correction of flexion deformity on the right hip after first-stage surgery with proximal tibial pin insertion for postoperative traction application (b)

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Postoperatively, the limb was kept on distal femoral heavy traction (12 kg) for 2 weeks [Figure 3]b.

Outcome and follow-up

After the 1st stage of the right hip THA patient, an upper tibial pin was applied for heavy skeletal traction to correct the residual flexion deformity of 8° and simultaneously the patient's general condition was built up for the left THA. After the left THA, the patient was again put on upper tibial skeletal traction for a week and was then mobilized full weight-bearing with a walker. Static quadriceps, pelvic lifting, and ankle pumping exercises were started from day 1 of surgery. Postoperative radiographs showed a good component placement [Figure 4].
Figure 4: Radiograph of the pelvis with both hip in AP view (a) and in the lateral projection (b), showing right THA with a good acetabular inclination and femoral component placement and cerclage wiring. AP: Anterior-posterior, THA: Total hip arthroplasty

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The patient was discharged on postoperative day 4 after the left THA following an uneventful surgical recovery. She was followed up twice weekly for 2 months and then at 6 months and 2 years after surgery. The radiographs at 2 years showed a good component position with no hardware complications [Figure 5]. At this point, the patient was ambulatory without support with an erect posture and no pain [Figure 6]. She resumed her college education and had no restriction of activities at the 2-year follow-up.
Figure 5: Postoperative radiograph AP view in the immediate postoperative period after both THA (a) and at 2-year follow-up period (b) showing good positioning of the acetabular and femoral components. THA: Total hip arthroplasty

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Figure 6: Clinical photograph at 2-year follow-up from front (a) and side (b) showing good posture and function. The patient walked pain-free without any difficulty at this point

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  Discussion Top

When AS leads to bilateral osseous ankylosed hips, considerable time has elapsed since the onset of the disease. Current literature reports satisfactory long-term survivorship for THA to 89.4% at 15 years, 70.2% at 20 years, and 57.9% at 25 years, hence it becomes the treatment of choice for these patients.[12] When this presents in adolescents or very young adults, the surgical challenge becomes even more pronounced than in our case. It is technically more difficult to perform THA in the osseous ankylosed hip than in nonankylosed hip because of the loss of surgical landmarks and the difficulty in restoring the joint mechanics.[11] The surgeon has to address certain parameters such as (1) identify and preserve the hip abductor muscles, (2) accurately identify the hip rotation center, (3) perform concentric reaming of the acetabular bone bed to achieve medialization and sizing of the component, (4) avoid placement of the acetabular cup in an excessively cephalic position, (5) restore ideal femoral offset to avoid impingement and instability, and (6) correction of leg length discrepancy.[13] Good surgical techniques lead to better clinical outcomes in most of these cases.

In our patient, bilateral THA was the best option in order to correct the severe flexion deformity. When the hip is ankylosed in a poor position, the anatomical relationships are distorted even more, as was the case in our patient. As regards synchronous or sequential THA procedure, there are pros and cons described in the literature for each.[6],[7],[14] Since the literature shows no difference in patient satisfaction or long-term clinical outcomes between simultaneous versus staged THA, it is best to base our decision on a case-to-case basis.[4] Our patient was nutritionally poor and hence it was decided to undertake both THA at an interval of 3 weeks after build-up for the second surgery. The average HHS improved from 43 points before surgery to 96 points at a follow-up of 24 months. Considering the severe flexion deformity, full correction of deformity by achieving complete extension of the hip intra operatively might have damaged blood vessels and nerves, hence we accepted <10° residual flexion deformity in our patient which did not compromise with her functional outcome.

Several surgical approaches have been described for THA in the ankylosed hip. Regardless of which surgical approach is used, the surgeon must ensure appropriate exposure and reduce tension on the soft tissues and neurovascular structures intraoperatively because, during THA, the femoral head cannot be dislocated through conventional operation, which may influence the operative field and operative procedure. Direct lateral approach was used in our case based on surgeon choice and familiarity. A trochanteric osteotomy was reported to improve visibility, although an associated increase in postoperative heterotopic ossification (HO) and overall operative complications (i.e., nonunion) has led to a recent move away from this technique.[9],[15] No trochanteric osteotomy was performed in our study. The advantages of performing the procedure without trochanteric osteotomy are ease of rehabilitation and avoidance of trochanteric osteotomy complications.

As regards the implant selection, the key is to anticipate the difficulties which would be encountered intraoperatively and keep the armamentarium of implants ready. In the situation such as these, the S-ROM implant is of great help in getting the implant position right in a distorted native anatomy. The notable advantages of using an S-ROM are the availability of small femoral diameter stem and ability to dial in the required anteversion/antetorsion even after reaming the femoral canal by virtue of the proximal sleeve. Choice of bearing remains a pivotal decision in these challenging cases where the patients are mostly of a very young age group. The stable ingrowth postoperatively in most research recommends cementless implants in AS patients.[5],[16] Traditionally, metal-backed bearings are the most commonly used material and there are very few studies on the ceramic-based prosthesis used for ankylosed/fused hips.[17] Given that the use of ceramic bearings is considered an effective way to prolong the life of the artificial prosthesis in THA for other indications such as osteoarthritis and osteonecrosis of the femoral head, these should be considered for ankylosed hips as well, especially in very young patients.[18],[19] There was no ceramic-related complication in our patient at 2-year follow-up.

Yang et al. found that AS patients have severe osteoporosis with associated bone loss in the cortical bone of the proximal femur, resulting in notable morphological changes in the proximal femur.[20] Therefore, the choice of implant is particularly important for long-term fixation and hip function in these patients. It is critical that such severe deformity be tackled with an implant which has modularity to tackle intraoperative problems such as proximal femoral deformity. Kang et al. showed in their study that the use of a proximal modular femoral stem (S-ROM) yielded a good outcome for complex primary hip arthroplasty.[21] In our study, preoperative analysis of narrow proximal femoral canal and severe flexion deformity warranted us to choose S-ROM proximal modular femoral stem (DePuy Johnson and Johnson Co., Warsaw, IN, USA) which allowed us to tackle the narrow femoral canal and dial in the desired amount of anteversion on table. This precise control of modularity and version enabled us to achieve a good component placement and, in turn, a good functional outcome in the postoperative follow-up period of 2 years. The S-ROM modular stem generates maximal contact between the stem and the endosteum in the metaphysis and the diaphysis. In the proximal part, we could maximize canal filling with the use of a sleeve, and in the distal part, the flute-like shape tolerates torsional forces better.

Mou et al. reported that AS increased perioperative and postoperative complications after THA.[7] Blizzard et al. showed a high incidence of complications including wound complication, polyethylene wear, revision, and dislocation.[22] Component malposition, abnormal spinopelvic mechanics, younger and more active than average patients, and higher functional demand all contribute to the increased complication rates. Tang and Chiu believed that the pelvic malrotation in the sagittal plane often seen in patients with AS can cause errors in cup positioning in AS patients.[23] In order to ensure proper component placement, we used intraoperative radiography and reduced the anteversion angle of the acetabular cup and increased the anteversion angle of the femoral prosthesis. Again, the use of modular femoral components aided greatly in achieving the target. In our case, there was no component malalignment and loosening at the last follow-up.

HO after THA is a major challenge, especially in AS patients. High rates of HO were reported in previous research, which ranged from 11.6% to 73.7% (mean: 35.2%), with a mean of 7.0% clinically important HO (Brooker Classes III and IV).[24] HO may present clinically with pain, impingement, decreased ROM, re-ankylosis, nerve irritation, and trochanteric bursitis. Kilgus et al. advocated that patients with complete hip ankylosis preoperatively may be at increased risk of formation of large amounts of heterotopic bone.[25] Considering the high risk of HO in our patient, we started her on 2 weeks of indomethacin prophylaxis, which has no adverse effects. At 2-year follow-up, our patient did have Grade 2 HO, but she was asymptomatic.

Learning points

  • Staged bilateral THA surgery in previously fused hips is a technically demanding procedure with well-known reported complications. This case demonstrates that using a lateral hip approach without trochanteric osteotomy can provide adequate exposure and enable the surgeon to perform the required surgical techniques in the presence of a good implant inventory
  • Performing the THA in previously fused hips in young patients can provide an excellent outcome and function, considering the amount of mental and social well being that is achieved due to the correction of severely deformed postures. It can be a life-changing experience for many patients like ours. Still, long-term follow-up is suggested for better assessment and accurate prognosis
  • Staging with a 4–6-week interval between the two procedures facilitates better rehabilitation in bilateral THA. The surgeon should not underestimate the complications, and the patient needs to be cautioned about the complications.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Vander Cruyssen B, Muñoz-Gomariz E, Font P, Mulero J, de Vlam K, Boonen A, et al. Hip involvement in ankylosing spondylitis: Epidemiology and risk factors associated with hip replacement surgery. Rheumatology (Oxford) 2010;49:73-81.  Back to cited text no. 1
Gensler LS, Ward MM, Reveille JD, Learch TJ, Weisman MH, Davis JC Jr. Clinical, radiographic and functional differences between juvenile-onset and adult-onset ankylosing spondylitis: Results from the PSOAS cohort. Ann Rheum Dis 2008;67:233-7.  Back to cited text no. 2
Chen HA, Chen CH, Liao HT, Lin YJ, Chen PC, Chen WS, et al. Factors associated with radiographic spinal involvement and hip involvement in ankylosing spondylitis. Semin Arthritis Rheum 2011;40:552-8.  Back to cited text no. 3
Ding L, Gao YH, Li YR, Liu JG, Li SQ, Qi X. Determinants of satisfaction following total hip arthroplasty in patients with ankylosing spondylitis. Int Orthop 2018;42:507-11.  Back to cited text no. 4
Bhan S, Eachempati KK, Malhotra R. Primary cementless total hip arthroplasty for bony ankylosis in patients with ankylosing spondylitis. J Arthroplasty 2008;23:859-66.  Back to cited text no. 5
Feng DX, Zhang K, Zhang YM, Nian YW, Zhang J, Kang XM, et al. Bilaterally primary cementless total hip arthroplasty for severe hip ankylosis with ankylosing spondylitis. Orthop Surg 2016;8:352-9.  Back to cited text no. 6
Mou P, Zeng WN, Chen Y, Zhou Z. Synchronous or sequential cementless bilateral total hip arthroplasty for osseous ankylosed hips with ankylosing spondylitis. BMC Musculoskelet Disord 2021;22:302.  Back to cited text no. 7
Kim YL, Shin SI, Nam KW, Yoo JJ, Kim YM, Kim HJ. Total hip arthroplasty for bilaterally ankylosed hips. J Arthroplasty 2007;22:1037-41.  Back to cited text no. 8
Bangjian H, Peijian T, Ju L. Bilateral synchronous total hip arthroplasty for ankylosed hips. Int Orthop 2012;36:697-701.  Back to cited text no. 9
Vosse D, de Vlam K. Osteoporosis in rheumatoid arthritis and ankylosing spondylitis. Clin Exp Rheumatol 2009;27:S62-7.  Back to cited text no. 10
Idulhaq M, Park KS, Diwanji SR, Yoon TR, Wie JS. Total hip arthroplasty for treatment of fused hip with 90 degrees flexion deformity. J Arthroplasty 2010;25:9.e5-9.  Back to cited text no. 11
Sodhi N, Mont MA. Survival of total hip replacements. Lancet 2019;393:613.  Back to cited text no. 12
Swanson MA, Huo MH. Total hip arthroplasty in the ankylosed hip. J Am Acad Orthop Surg 2011;19:737-45.  Back to cited text no. 13
Morcos MW, Hart A, Antoniou J, Huk OL, Zukor DJ, Bergeron SG. No difference in major complication and readmission rates following simultaneous bilateral versus unilateral total hip arthroplasty. J Arthroplasty 2018;33:2541-5.  Back to cited text no. 14
Wang W, Huang G, Huang T, Wu R. Bilaterally primary cementless total hip arthroplasty in patients with ankylosing spondylitis. BMC Musculoskelet Disord 2014;15:344.  Back to cited text no. 15
Xu J, Zeng M, Xie J, Wen T, Hu Y. Cementless total hip arthroplasty in patients with ankylosing spondylitis: A retrospective observational study. Medicine (Baltimore) 2017;96:e5813.  Back to cited text no. 16
Park KS, Yoon TR, Lee TM, Ahn YS. Ceramic on ceramic hip arthroplasty in fused hips. Indian J Orthop 2015;49:336-41.  Back to cited text no. 17
[PUBMED]  [Full text]  
Lee YK, Ha YC, Yoo JJ, Koo KH, Yoon KS, Kim HJ. Alumina-on-alumina total hip arthroplasty: A concise follow-up, at a minimum of ten years, of a previous report. J Bone Joint Surg Am 2010;92:1715-9.  Back to cited text no. 18
Higuchi Y, Seki T, Takegami Y, Komatsu D, Morita D, Ishiguro N. Same survival but higher rate of osteolysis for metal-on-metal ultamet versus ceramic-on-ceramic in patients undergoing primary total hip arthroplasty after 8 years of follow-up. Orthop Traumatol Surg Res 2018;104:1155-61.  Back to cited text no. 19
Yang P, Wang CS, Wang KZ, Shi ZB, Gong FL. Selection of femoral prosthesis in total hip replacement for ankylosing spondylitis. Di Yi Jun Yi Da Xue Xue Bao 2005;25:1468-73.  Back to cited text no. 20
Kang JS, Moon KH, Kim RS, Park SR, Lee JS, Shin SH. Total hip arthroplasty using S-ROM prosthesis for dysplastic hip. Yonsei Med J 2011;52:655-60.  Back to cited text no. 21
Blizzard DJ, Penrose CT, Sheets CZ, Seyler TM, Bolognesi MP, Brown CR. Ankylosing spondylitis increases perioperative and postoperative complications after total hip arthroplasty. J Arthroplasty 2017;32:2474-9.  Back to cited text no. 22
Tang WM, Chiu KY. Primary total hip arthroplasty in patients with ankylosing spondylitis. J Arthroplasty 2000;15:52-8.  Back to cited text no. 23
Ye C, Liu R, Sun C, Lin J, Li H, Re H, et al. Cementless bilateral synchronous total hip arthroplasty in ankylosing spondylitis with hip ankylosis. Int Orthop 2014;38:2473-6.  Back to cited text no. 24
Kilgus DJ, Namba RS, Gorek JE, Cracchiolo A 3rd, Amstutz HC. Total hip replacement for patients who have ankylosing spondylitis. The importance of the formation of heterotopic bone and of the durability of fixation of cemented components. J Bone Joint Surg Am 1990;72:834-9.  Back to cited text no. 25


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