Reconstruction of Acetabular and Femoral Bone Defects With Impaction Bone Grafting in Revision Hip Arthroplasty: A Case Report

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Abstract

Background. For many years, the main reasons for revision surgeries after hip arthroplasty remain aseptic loosening and osteolysis, which lead to formation of bone defects of various size and localization. Given the relatively young age of patients undergoing revision, the methods of biological restoration of the bone tissue, such as impaction bone grafting (IBG), are of particular interest.

Aim of the report — to demonstrate the delayed outcome of impaction bone grafting using compacted morselized bone allograft.

Case presentation. Complicated clinical case of a 62-year-old patient with Paprosky type IIA bone deficiency in the acetabulum and Paprosky type II bone deficiency in the proximal femur with aseptic loosening of the acetabular and femoral components of the hip prosthesis is presented. During revision arthroplasty with cemented components, IBG of the acetabulum and femur was performed with a reconstructive mesh augmentation of the acetabulum using Stryker X-Change technology. Bone allograft prepared with the use of heat disinfection method served as an osteoplastic material. Follow-up period was 4 years. Control X-rays demonstrate restoration of the center of rotation of the hip, presence of bone masses in the areas of pelvic and femoral bone defects, absence of osteoplastic material resorption and migration of implants during the follow-up period. Clinical assessment shows an improvement of the Harris Hip Score from 34 to 85 points.

Conclusion. Obtained results showed the efficacy of impaction bone grafting with the bone allograft prepared with the use of heat disinfection method in the mid-term period.

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BACKGROUND

The number of revision hip arthroplasties is increasing annually. This type of intervention is characterized by a higher cost compared to primary hip replacement as it requires a large stock of various implants, an appropriate instrumental support, the use of additive technologies, bone grafting, and the need for specialists experienced in revision arthroplasty, which ultimately affects expenses [1, 2]. This trend is typical both for countries with intensive development of primary arthroplasty and those without significant growth. In the former case, despite the low growth rate of revision arthroplasties, the total number of these surgeries is increasing annually [3]. In the latter case, the increase of number of revision interventions is significantly higher than that of primary surgeries [1]. Long-term results of revision surgeries are characterized by a higher complication rate than primary surgeries. Five-year survival rates after various revision surgeries range from 67.0 to 84.8% [4]. Aseptic loosening and osteolysis have been the main causes of revision interventions after hip arthroplasty for many years, leading to bone defect formation of various size and localization [1, 3, 5, 6, 7, 8]. Given the relatively young age of patients undergoing revision, the methods of biological restoration of the bone tissue, such as impaction bone grafting (IBG), are of particular interest [9].

The aim of the report is to demonstrate the delayed outcome of impaction bone grafting using compacted morselized bone allograft.

CASE PRESENTATION

A 62-year-old patient was admitted with complaints of pain in the left hip, significant restriction of movements, shortening of the left leg and lameness.

Status localis. The patient walks on his own using crutches. The distance he is able to walk does not exceed 300 m. Examination revealed a relative shortening of the left lower limb by 2 cm. The Harris hip score is 34 points.

Anamnesis. Left hip replacement with W. Link cemented prosthesis was performed 13 years ago. In the postoperative period there were dislocations of the femoral component, for which a revision surgery with replacement of the pelvic component was performed. Pain in the left hip joint has been disturbing the patient periodically for 11 years and has been gradually progressing. Restriction of movement and shortening developed. Two years ago, due to severe pain syndrome and prevalent dysfunction, the right hip replacement with SL-Plus/R3 (Smith&Nephew) prosthesis was performed for aseptic necrosis of the femoral head.

Secondary diagnosis. Stage 3 essential hypertension, drug-controlled 1st grade arterial hypertension, cardiovascular risk 4, functional class 2 of the stage 1 CHF. CHD: artificial pacemaker (2017). Transitory atrioventricular block g rade 1. Lower extremity varicose vein disease, CVD grade 1, postthrombophlebitic syndrome of the left iliofemoral segment, the right popliteotibial segment, complicated by PATE. Condition after implantation of permanent inferior vena cava filter (2011).

 

Fig. 1. Plain pelvis X-ray before revision of the left hip (explanation in the text)

 

Preoperative X-rays dated 30/07/2018 showed (Fig. 1):

˗ pelvic prosthetic component loosening, Paprosky type IIA defect [10];
˗ femoral component loosening and subsidence, Paprosky type II defect of the femur [11];
˗ varus remodeling of the left femoral intramedullary canal;
˗ Brooker stage 3 heterotopic ossification of the left hip joint;
˗ right hip arthroplasty.

In the preoperative period, the left hip arthrocentesis was performed, followed by cytologic and microbiologic studies of synovial fluid aspirate. No data indicating the presence of infectious process in the joint were obtained.

On 02.08.2018, the left hip revision arthroplasty using Stryker Exeter prosthesis and IBG of the acetabulum and proximal femur with bone allograft and augmentation of the supraaceta-bular bone mass with reconstructive mesh were performed.

The approach was performed along the old postoperative scar on the anteroexternal surface of the thigh. The anterior portion of the gluteus medius muscle was isolated, cut off and retracted using instruments. The bone bed and the components of the prosthesis were separated from the scar tissues and bony overgrowths. On revision of the components, the stem and the acetabular component of the prosthesis were completely unstable. The femoral component was exteriorized and removed. The acetabular component was removed without technical difficulties. Tissue examination did not reveal any significant inflammatory changes. The acetabulum and the femoral intramedullary canal were cleared of scar tissue, granulations, and fibrous membrane. On examination, a segmental defect of the posterior edge of the acetabulum was detected, but in general, the limitation was preserved. The defect was classified as type III according to the AAOS classification [13]. It was repaired using a reconstructive mesh fixed with two screws.

In order to replace the bone defect, bone grafting material from the hospital bone bank was prepared in the form of allogeneic bone chips of 8-10 mm in diameter for the acetabular plasty and 5-6 mm for the femoral IBG (Fig. 2). The size and the quality of bone chips are important for the early mechanical stability of the impacted bone allograft. The particles should be of the largest size that can be impacted between the acetabular bone walls and the impactor.

 

Fig. 2. Production of bone chips: a — for acetabular IBG; b — for femoral IBG prepared with a bone mill

 

IBG of the acetabulum was performed using Stryker X-Change* revision instruments. After cement-based volume restoration, a 58 mm Stryker Contemporary acetabular component was implanted. Using Stryker X-Change revision instruments, impaction grafting of the femur was performed with impactor No. 4 with offset 44. Reduction test with head -4 (32 mm) was performed. Joint stability test showed no dislocation. Stryker Exeter stem was implanted into the prepared cement-based bed. The head -4 (32 mm) was permanently fixed to the neck of the femoral component after cement hardening. Prosthesis was assembled in the wound. Surgical wound was sutured layer by layer, aseptic dressing was applied.

 

Fig. 3. Plain pelvis X-rays after the left hip revision: a — control X-ray immediately after the surgery (02/08/2018): even distribution of osteoplastic material, restoration of the center of rotation of the joint; b — 4 months after the surgery (24/12/2018): position of components remains unchanged, no migration of the acetabular and femoral components is observed, the state of osteoplastic material is satisfactory with no signs of resorption; radiolucent lines at the osteoplastic material-cement interface are absent; c — 4 years after the surgery (24/10/2022): X-ray signs of restructuring of osteoplastic material in the pelvic and femoral bones, radiolucent lines at the osteoplastic material-cement interface are absent, position of components remains unchanged with no signs of migration or subsidence

 

In the control X-ray dated 03.08.2018 after revision arthroplasty, acetabular reconstruction with mesh and IBG and proximal femoral reconstruction with IBG using Stryker Exeter cement stem, the bone grafting material filled the acetabulum evenly (Fig. 3 a). The posterior edge of the acetabulum is augmented with a reconstructive mesh, the femoral component is positioned correctly, parallel to the femoral axis, the osteoplastic material fills the femoral intramedullary canal evenly, with the same intensity in all zones. Radiolucent lines at the osteoplastic material-cement interface are not observed.

In the postoperative period, the patient was ambulated; the 1st stage of rehabilitation was performed. No complications were observed. The patient was discharged on the 14th day after the surgery with the recommendation of limited weight bearing on the operated limb for 12 weeks.

The results of revision surgery after 4 months and 4 years are shown in Figures 3 b and 3 c, respectively.

On physical examination, the patient has no complaints of pain. There is a slight lameness. The patient moves on his own without any means of support, uses a cane occasionally during long walks, does not experience serious social and everyday restrictions. The HHS is 85 points.

DISCUSSION

Various methods are currently available to restore the bone deficit, ranging from filling bone defects with bone cement and application of various modular systems with metal augments to the use of patient-specific 3D constructs [14, 15]. It is very important to minimize bone deficiency, especially in young patients, and to try to restore the bone mass. In fact, only one out of many techniques can partially solve this problem, which is IBG using allogeneic bone [16].

The aim of IBG is to achieve stable fixation of the implant using compaction of the morselized allogeneic bone graft and subsequently to provide conditions for reparative regeneration by gradual replacement of allogeneic bone with the patient's own bone. This is a rather attractive technique that allows one to anticipate bone regeneration both structurally and functionally. On the other hand, it is difficult to balance between achieving primary stable fixation of the implant and a long biological process of allogeneic bone remodeling [17, 18, 19, 20].

The outcome of revision arthroplasty was always worse than that after primary arthroplasty. The smooth endosteal surface remaining after removal of the primary implant does not allow to achieve reliable fixation of the bone cement on the surface, which leads to early loosening of the cemented prosthesis. IBG solves this problem, which is confirmed by long-term results [21, 22, 23, 24].

The use of IBG is possible under certain conditions in a bone wound. First, bone allograft must be retained inside the bone defect; second, it must be structural and able to withstand mechanical load; third, it must create conditions for reliable fixation of the cemented pelvic component of the prosthesis. Creation of such conditions is possible in case of a specific form of the acetabular bone defect — the most important criterion is its limitation. In primary pathology, an example of such defects is the acetabular roof protrusion in cases of systemic connective tissue diseases or posttraumatic defects [22, 25, 26].

A prerequisite for IBG is the integrity of the pelvic support structures: anterior and posterior columns (Paprosky types IIA, IIIB defects). At the same time, cavitary bone defects with minor segmental deficit (AAOS type III) can be transformed into completely limited ones with the help of reconstructive meshes. In this case, the use of IBG is also possible [21, 22].

One of the key points of successful bone defect grafting is the high-quality preparation of osteoplastic material [27, 28, 29]. Studies have shown that bone fragments of 8-10 mm in diameter provide the best initial stability [21, 30]. Another advantage of large particles is that they form a more porous and more permeable compacted bone layer. This is important since reduced porosity can impede the neoosteogenesis in compacted bone masses. In addition, comparison of bone ingrowth in compacted material with non-ideal particle size distribution (non-ideal distribution ensures at each level that voids between larger particles are open and not filled by smaller particles) with ideal particle distribution showed increased bone tissue formation [31, 32].

CONCLUSION

The clinical example of impaction bone graf-ting using osteoplastic material from the allogeneic femoral head prepared by heat disinfection method shows the possibility of bone restoration in case of defects. Bone grafting efficiency has been shown in the mid-term in a rather uncommon case where it was performed both in the ace-tabular area and in the proximal femur. Further studies are required to confirm the efficacy of impaction bone grafting in revision hip arthroplasty in case of bone deficiency.

DISCLAIMERS

Author contribution

Golnik V.N. — treatment of patient, study concept and design, data collection and processing, the analysis of data, the drafting of the article.

Peleganchuk V.A. — data analysis and interpretation, drafting the article.

Batrak Yu.M. — data collection and processing, literature search and analysis, writing the article.

Pavlov V.V. — data analysis and interpretation, drafting the article.

Kirilova I.A. — the literature search and analysis, the analysis and interpretation of data, the drafting of the article.

All authors have read and approved the final version of the manuscript of the article. All authors agree to bear responsibility for all aspects of the study to ensure proper consideration and resolution of all possible issues related to the correctness and reliability of any part of the work.

Funding source. This study was not supported by any external sources of funding.

Disclosure competing interests. The authors declare that they have no competing interests.

Ethics approval. Not applicable.

 

* https://www.bizwan.com/_mydoc/stryker/Hip/049%20X-change%20Revision%20Instruments%20Surgical%20Technique%20-%20Femur%20and%20Acetabulum.pdf

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About the authors

Vadim N. Golnik

Federal Center for Traumatology, Orthopedics and Endoprosthetics

Email: vgolnik@mail.ru
ORCID iD: 0000-0002-5047-2060

зав. отделением травматологии и ортопедии №2

Russian Federation, Barnaul

Vladimir A. Peleganchuk

Federal Center for Traumatology, Orthopedics and Endoprosthetics

Email: 297501@mail.ru
ORCID iD: 0000-0002-2386-4421

Dr. Sci. (Med.)

Russian Federation, Barnaul

Yuriy M. Batrak

Federal Center for Traumatology, Orthopedics and Endoprosthetics

Email: 297501@mail.ru
ORCID iD: 0000-0003-0489-1480

Cand. Sci. (Med.)

Russian Federation, Barnaul

Vitaliy V. Pavlov

Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan

Email: pavlovdoc@mail.ru
ORCID iD: 0000-0002-8997-7330

Dr. Sci. (Med.)

Russian Federation, 17, Frunze st., Novosibirsk, 630091

Irina A. Kirilova

Novosibirsk Research Institute of Traumatology and Orthopedics n.a. Ya.L. Tsivyan

Author for correspondence.
Email: irinakirilova71@mail.ru
ORCID iD: 0000-0003-1911-9741

Dr. Sci. (Med.), Deputy Director for Research

Russian Federation, 17, Frunze st., Novosibirsk, 630091

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2. Fig. 1. Plain pelvis X-ray before revision of the left hip (explanation in the text)

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3. Fig. 2. Production of bone chips: a — for acetabular IBG; b — for femoral IBG prepared with a bone mill

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4. Fig. 3. Plain pelvis X-rays after the left hip revision: a — control X-ray immediately after the surgery (02/08/2018): even distribution of osteoplastic material, restoration of the center of rotation of the joint; b — 4 months after the surgery (24/12/2018): position of components remains unchanged, no migration of the acetabular and femoral components is observed, the state of osteoplastic material is satisfactory with no signs of resorption; radiolucent lines at the osteoplastic material-cement interface are absent; c — 4 years after the surgery (24/10/2022): X-ray signs of restructuring of osteoplastic material in the pelvic and femoral bones, radiolucent lines at the osteoplastic material-cement interface are absent, position of components remains unchanged with no signs of migration or subsidence

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