|
 
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| ORIGINAL ARTICLES |
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| Year : 2023 | Volume
: 38
| Issue : 1 | Page : 54-70 |
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A functional and radiological outcome of uncemented total hip arthroplasty in young adults
Johney Juneja1, Dharmendra Jatav1, Mahendra Prakash Jain1, Naresh Saini1, Anurag Talesra1, Anamendra Sharma1, Ramesh Sen2
1 Department of Orthopaedic of Rabindranath Tagore Medical College Hospital Udaipur, Udaipur, Rajasthan, India
2 Orthopaedic Department, Max Superspeciality Hospital Mohali, Mohali, Punjab, India
| Date of Submission | 27-Jan-2023 |
| Date of Acceptance | 17-Feb-2023 |
| Date of Web Publication | 20-Apr-2023 |
Correspondence Address:
Johney Juneja
Department of Orthopaedic of Rabindranath Tagore Medical College Hospital Udaipur, Udaipur 313001, Rajasthan
India
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/jbjd.jbjd_7_23
Background: End-stage arthritis in young patients requires surgical intervention. Total hip arthroplasty (THA) remains the treatment of choice for restoring function and activity in end-stage hip arthritis. The medium-term outcome of uncemented THA in the Indian population is less studied. Hence, this study was taken up with aim to study clinical and radiological outcomes of uncemented THA in patients with age less than 40 years. Materials and Methods: This study was a prospective study done on 50 patients admitted to RNT Medical College and M.B. Hospital Udaipur during December 2021 to September 2022 chosen based on the inclusion and exclusion criteria. Patients were informed about the study in all respects, and written informed consents were obtained. The follow-up period was at 12th day, 1 month, 3 months, 6 months, and 9 months for functional outcome assessment and radiological evaluation. Patients were evaluated preoperatively and postoperatively. Inclusion criteria: (1) adult age group 20–50 years; (2) patients with secondary arthritis of hip (posttraumatic, avascular necrosis of femoral head, or ankylosing spondylitis). Exclusion criteria: (1) active infection of the hip joint or any other active infection in body; (2) patient with uncontrolled diabetes mellitus, unstable cardiac disease, and with other grave medical concerns or severe comorbidity; (3) neuropathic joint; (4) not willing to participate; (5) with vascular insufficiency. Results: Bony ingrowth with no evidence of loosening was seen consistently both on femoral and acetabular side in all patients on X-ray. No statistically significant association was found between initial alignment of the femoral component and clinical outcome. Conclusions: Uncemented THA can be used in young patients with excellent to good functional and radiological outcome at mid-term follow-up, high satisfaction rate, and lower rate of complications. Keywords: Functional outcome, Harris Hip Score, uncemented total hip arthroplasty, young adults
How to cite this article:
Juneja J, Jatav D, Jain MP, Saini N, Talesra A, Sharma A, Sen R. A functional and radiological outcome of uncemented total hip arthroplasty in young adults. J Bone Joint Dis 2023;38:54-70 |
How to cite this URL:
Juneja J, Jatav D, Jain MP, Saini N, Talesra A, Sharma A, Sen R. A functional and radiological outcome of uncemented total hip arthroplasty in young adults. J Bone Joint Dis [serial online] 2023 [cited 2023 Jun 7];38:54-70. Available from: http://www.jbjd.in/text.asp?2023/38/1/54/374437 |
| Introduction | |  |
Young adults may suffer from hip arthritis due to various etiological disorders such as ankylosing spondylitis, posttraumatic arthritis, or avascular necrosis (AVN) of femoral head. It leads to disability severely compromising activities of daily living in these young patients. End-stage arthritis in such patients requires surgical intervention. In earlier days, hip arthrodesis or resection arthroplasty was the preferred options, but since the last couple of decades, total hip arthroplasty has emerged as a successful option with good functional results.[1] With the advances in design and materials used for implants, the success rate has increased in even high-demand patients. Thus, total hip arthroplasty remains the treatment of choice for restoring function and activity in end-stage hip arthritis.[1]
Although total hip arthroplasty was earlier considered only for elderly patients, good functional results have been reported by multiple studies in younger patients.[2],[3]
Patients were evaluated preoperatively and postoperatively. After discharge patients were followed up at 3 months, 6 months, and yearly thereafter. For functional evaluation, multiple factors were taken into consideration. Activity level used in study is defined by Johnston et al.[68] as follows: heavy manual labor defined as lifting 23–45 kg or engaged in vigorous sports, moderate manual labor defined as lifting 23 kg or less and involved in moderate sports, light labor included heavy lifting, house cleaning, and walking <5 km. Semisedentary indicated white collar job or light housekeeping. Sedentary activity indicated minimal capacity for walking, and bedridden was defined as being confined to a wheelchair or bed. Harris Hip Score was used to evaluate the functional outcome at regular follow-up.[5]
Radiological evaluation was done with anteroposterior and lateral X-rays. The immediate postoperative X-rays were compared with the follow-up X-rays. On X-rays, Gruen zones were identified and radiolucencies were searched.[6] Radiolucencies with a scalloped or cystic appearance or >2 mm in width were recorded as osteolysis.
Subsidence was evaluated by measuring the distance the stem has settled. If the stem settled >4 mm, it was considered as subsidence.[7] Femoral component alignment was evaluated. It was considered neutral if the line passing through center of implant and the femur were within 3°. A difference of >3° indicated a varus or valgus orientation.[8]
| Aim and Objectives | | |
The aim of the study:
- To study the functional and clinical outcomes of uncemented total hip arthoplasty using the modified Harris Hip Score.
- Radiological assessment for outcome evaluation.
- To study advantage and disadvantage of uncemented total hip arthroplasty in young adults.
| Materials and Methods | | |
This study was a prospective study done on 50 patients admitted to RNT Medical College and MB Hospital Udaipur during December 2021–September 2022 chosen based on the inclusion and exclusion criteria.
Patients were informed about the study in all respects, and written informed consents were obtained.
The follow-up period was at 12th day, 1 month, 3 months, 6 months, and 9 months for functional outcome assessment and radiological evaluation.
Inclusion criteria
- - Adult age group 20–50 years.
- - Patients with secondary arthritis of hip (posttraumatic, AVN of femoral head, or ankylosing spondylitis).
Exclusion criteria
- - Active infection of the hip joint or any other active infection in body.
- Patient with uncontrolled diabetes mellitus, unstable cardiac disease and with other grave medical concerns or severe comorbidity.[9]
- - Neuropathic joint.
- - Not willing to participate.
- - With vascular insufficiency.
Statistical analysis
ALL COLLECTED DATA WERE ENTERED USING MICROSOFT MS EXCEL and analyzed by EPI Info Software for qualitative data. Quantitative data represented as mean ± SD, diagrammatical presentation, and in percentage.
Methods
Follow-up period protocol
A standard protocol was used in the postoperative period. Follow-up visits are made at 1 month, 3 months, 6 months, and 9 months and periodically thereafter. Routine plain radiographs are taken and assessed for loosening, migration, and osteolysis during follow-up visits.
Postoperative radiological assessment
Femoral component
- By using Moss Template Center of Rotation of hip compared to normal side.
- Fixation of femoral component was assessed by presence of optimal contact of stem with both lateral and medial endosteal cortical surfaces for about 5 cm.
- Tip of the stem positioned in neutral without any varus–valgus angulation.
- Level of the Greater Trochanter tip which corresponds to the center of femoral head.
- Level of both sides lesser trochanter for any limb length discrepancies.
- Seating of collar of the stem correctly over the calcar femorale.
- Restoration of both vertical and medial offset compared to normal side.
- Orientation of neck to the vertical offset. In valgus hip, the medial offset was smaller than the vertical offset, so the center of head lies superior to the level of trochanter tip. In varus hip, medial offset larger than vertical offset, so the center of head lies inferior to level of trochanter tip.
- Gruen et al. zonal analysis for loosening
The femoral stem was separated into seven zones. Each zone was analyzed for radiolucency and radiopaque lines and for bony apposition.
- 10. Bending of stem was assessed by angle made between a line drawn along the lateral surface of distal stem and another line drawn through the center of neck and head.
- 11. femoral component analysis using Einzel-Bild-Röntgen-Analyse method for measuring the migration of stem.
Einzel–Bild–Roentgen–Analyze method was used to assess the femoral component migration. Compared with Roentgen stereophotogrammetric analysis, this method has the specificity of 100%. This is an accurate method to assess stability within particular period. Migration of prosthetic implants early is predicted to later failure. This method gives information regarding about subsidence and the lateral and medial distance between prosthetic margin and bone margin.
There are four different reference lines to describe the migration.
- a Tip of greater trochanter to stem shoulder.
- b Tip of greater trochanter to center of head.
- c Tip of lesser trochanter to shoulder head.
- d Tip of lesser trochanter to center of head.
Acetabular component
Assessed by the following parameters:
- Optimal size and correct seating of cup without polar gap.
- Correct inclination of the cup to the tear drop level.
Excessive inclination > 45° results in dislocation of prosthesis on adducting the limb. Degree of ante-version—normal ante-version of acetabulum was about 15°–20°. The version was determined by position of the anterior and posterior half of circumferential wires in the cup.
- 3. Polyethylene wear was measured by the distance of migration of femoral head into polyethylene. It was assessed by superolateral penetration of femoral head of >2.5 mm.
- 4. Posterosuperior quadrant is the safest zone for using transacetabular screws.
- 5. The acetabular component loosening was described by DeLee and Charnley.
Loosening is measured in three zones of acetabulum.
- 6. Reinforcement of acetabulum with rings, cages, and impaction grafting are noted.
- 7. Protrusion of cup: The radiographic hallmark of protrusion of hip is the migration of the cup medially beyond the ilio-ischial line (Kholer’s line).
Radiologically patients were classified into:
- Group I—No evidence of loosening (migration, osteolysis).
- Group II—Evidence of loosening present on radiographs but the patient is asymptomatic.
- Group III—Evidence of loosening in a symptomatic patient.
Functional outcome assessment
Assessment was done by using the modified Harris Hip Score. Harris Hip Score has the following components:
- Pain—(44 points maximum).
- Gait (walking maximum distance) (33 points maximum).
- Functional activity (14 points maximum).
- Absence of deformity (4 points maximum).
- Range of motion (5 points maximum).
- Total—100 points.
The Harris Hip Score was graded as follows:
| Observations | | |
Age distribution in our study
In the present study on evaluation of the age distribution, we found that of the 23 cases in the study, most patients belonged to the category 30–39-year age group [Table 1]. The mean age was 36.1 years.
Sex distribution in our study
Our study included 38 males (76%) and 12 females (24%) [Table 2].
Side distribution
Various indications
| Analysis and Results | | |
In our study, majority of patients (48%) had AVN of femoral head and 32% of patients had chronic arthritis of hip.
Ten percent of patients were treated with cancellous screws fixation for fracture neck of femur; subsequently patient developed AVN of femoral head which were treated [Table 3] by uncemented total hip arthroplasty, 6% of patients had fracture nonunion neck of femur and 4% of cases had developmental dysplasia of hip with secondary arthritis.
All patients had severe pain with limitation of daily activities of living. Preoperative assessment with Harris Hip Score is done in all cases.[10]
The surgical approach used depends on the preference of the operating surgeon. Hardinge’s direct lateral approach was used in 72% of cases and Moore’s posterior approach used in 28% of cases.[11]
“Ring Loc” standard cup with highly cross-linked polyethylene liner was used in all cases. “Taper Loc” porous-coated femoral stem was used in all cases. Follow-up period ranged from 1 to 2 years.[12]
All patients were radiologically assessed for the following parameters.
Femoral component
Prosthesis level above the lesser trochanter averages about 1.5 cm.
Optimal position of the prosthesis.
Canal fill of the stem in anteroposterior diameter averages about 80%.
Intraoperative femoral fracture was seen in one case which was treated by cerclage and femoral locking plate.
Aseptic loosening of femoral stem in Gruen zones 3, 4, 5 is seen in one case.[13]
There was no evidence of calcar resorption indicating no subsidence in any of the case.
There was no evidence of osteolysis around femoral stem as indicated by radiopaque line formation in any of the case.
Majority of the stem had shown good osteointegeration.
Acetabular component
Correct positioning with 45° inclination and 15° ante-version was seen in 86% of cases.[14]
Acetabular component with overhanging margins beyond the superolateral rim was seen in one case.[15]
Correct seating without any polar gaps and intimate contact with subchondral bone is seen in 90% of cases.[16]
Transacetabular screws to secure the cup firmly to the acetabulum used in all cases.
Acetabular loosening in Charnley and DeLee zone 2 was seen in one case.
Pelvic osteolysis not seen in any case.
No protrusion of the cup into the acetabulum is encountered in our study.
In a case of dysplastic hip, acetabular reconstruction was done using autologous iliac crest bone graft. In the subsequent follow-up period, the graft was found to be incorporated completely.[17]
Postoperative sciatic nerve palsy was seen in zero cases.
Deep vein thrombosis was seen in zero cases.
Preoperative hip score in our study was as follows:
Postoperative Harris Hip Score as follows:
The poor results were seen in two cases [Table 4]. In one case, poor result was due to postoperative dislocation and shortening. This patient had suffered from severe arthritis of hip. In another case, poor result was due to noncompliance to follow-up postoperative instructions and mobilization [Table 5].
The fair to poor results were due to:
- - Severe arthritis with restriction of daily activities of living.
- - Intraoperative femoral fracture in two cases [Table 6].
- - Deep vein thrombosis in four cases.
- - Postoperative sciatic nerve palsy in two cases [Table 7].
- - Persistent anterior thigh pain in three cases.
- - Limb length discrepancy with a shortening of 1 cm in two cases and lengthening of 2 cm in three cases was seen.
| Results | | |
- - In our study, most of the patients belong to the age group of 30–40 years (46%).
- - Males (76%) predominate in our study.
- - Avascular necrosis of femoral head is the most common indication in our study.
- - Uncemented total hip arthroplast was done in all cases. In bilateral affected cases, severely operated limb was operated first.
- - Ring loc acetabular cup and Taper loc porous-coated femoral stem was used in all cases.[18]
- - Eighty percent of cases had femoral stem in neutral position with osteo-integration.
- - Optimal cup size with 45° inclination at the tear drop level was seen in 86% of cases.
- - Seventy-four percent of cases had good functional outcome with Harris Hip Score of 80–89%.[19]
Bony ingrowth was seen consistently both on femoral and acetabular side in all patients on X-ray. No femoral or acetabular component loosening was seen on X-rays. Three patients had shown subsidence of 2 mm during 3-month follow-up, but they remained stable at 5-year follow-up.
No statistically significant association was found between initial alignment of the femoral component and clinical outcome.
Incidence of various complications
- - Postoperative dislocation in one case (2%) [Table 8]
- - Intraoperative femoral fracture in one case (2%)
- - Postoperative sciatic nerve palsy in zero cases (0%)
- - Postoperative deep vein thrombosis in zero cases (0%) [Table 9]
- - Femoral stem aseptic loosening in one case (2%)
- - Acetabular cup loosening in one case (2%)
- - Limb length discrepancy in three cases (6%)
- - Anterior thigh pain in one case (2%)
- - Heterotopic ossification in zero cases (0%) [Table 10]
- Case I: Excellent functional outcome diagnosis- chronic arthritis of bilateral hip.
- Case II: Left hip grade 3 protrusion (divergent type) with osteoarthritis.
Thirty-year-old female with 18-year-old past history of septic arthritis with healed sinuses over saccral region, her C-reactive protein (CRP), hip aspirate, and intraop tissue culture was normal impaction bone grafting and sizing/mouth opening of acetabulum[34]
- Case III—Secondary osteoarthritis of left hip postimplant failure.
- Case IV—Chronic arthritis left hip.
- Case V: Right osteoarthritic hip with mushrooming of femoral head and superolateral bone loss of acetabulum (Paprosky type 2b).
- Case VI: Left hip osteoarthritis due to 25-year-old malunited acetabula fracture with posterior wall ballooning
- Case VII: Eight-month-old right posterior column fracture treated with multihole cup and impaction grafting. Intraop we found in posterior column was stable; so we used multihole cup with screw in superior–inferior quardant so that cup acts as internal fixator/cage. We achieved primary stability.[35]
Complications
Postoperative dislocation prereduction X-ray
Post reduction X-ray
Complications
- 1. Intra-OP femoral fracture treated
- 2. Heterotopic ossification
| Discussion | | |
This prospective study is conducted to analyze the radiological, clinical, and functional outcome of uncemented total hip arthroplasty for various indications.[36]
The results of the study are compared with the known similar studies reported in literature.
In Alexander et al.’s[82] study also, the most common indication is chronic arthritis (89%).
No case of dysplastic hip was reported in this study.
Femoral stem alignment in comparison with other studies.
In Bourne et al.’s[60] study, the alignment is
Functional outcome in comparison with other studies shown in [Table 5].
The follow-up outcomes in other studies are Schramm et al.[23]
Reasons for the failure of uncemented total hip arthroplasty as described by other studies:
Aldinger et al.[24]—high rate of cup loosening
Siebold et al.[26] and Aldinger et al.[28]
- - Polyethylene wear with subsequent osteolysis.
- - High rate of femoral stem loosening.
The incidence of various complications as compared to other studies are shown in [Table 11].
Acetabular loosening
Loosening: Radiographs are taken with proper positioning and rotation is needed to diagnose loosening.
Cement-less femoral stem fixation is classified by Engh et al.
- Stable bone ingrowth
- Fibrous ingrowth
- Unstable implant
Subsidence or migration of implant may occur during early postoperative period to attain stable position. In spite of early subsidence, stable bone in-growth can occur, but late subsidence lead [Figure 1] to unstable implant. Small amount of migration cannot be identified with routine radiographs. Roentgen stereophotogrammetric analysis is used as a newer technique [Table 11]. Progressive bead shedding visible on serial radiographs is found to be significant. It indicates micromotion at bone-stem interface.
Acetabular cement-less components
Acetabular cup loosening is rare after uncemented total hip arthroplasty.[37] Loosening of acetabular cup fixation is described by Engh et al.
- stable fixation
- progressive into unstable
- definite unstable
Progressing radiolucent lesions indicate unstable implant.
Diagnosis of loosening can be made by serial monitoring of radiographs.[38] Radiolucent area can occur due to infection also. But aseptic loosening can occur before patients present with symptoms [Figure 2].
In this situation, progressive monitoring of radiographs is essential. Patients present with complaints of “start-up” pain that decreased after walking for some distance and also give history of limb moving outward and limb becoming shorter.[39] Symptoms with progressive radiological findings confirm the diagnosis [Figure 3] . Asymptomatic patients with progressive radiologic findings also need revision surgery as early as possible. Subsidence can occur due to loosening of implants. RSA method is highly sensitive to find a small change in position.[40] | Figure 3: (a) Preop bilateral O hip. (b) Postop. (c) Case 1—clinical picture
Click here to view |
Periprosthetic femoral stem fracture
Femur fracture can occur during surgical procedure. Due to weak bone in conditions like osteoporosis and patients with rheumatoid arthritis, femur can get fractured while dislocating the hip joint.[41] If dislocation of head is difficult, check for osteophytes and soft tissue contracture. These problems have to be corrected before dislocating femoral head. Protrusion [Figure 4] of femoral head and revision procedure are risk factors.
Fracture may occur during broaching or femoral stem implantation.[42] Broach is used for removal of cancellous bone [Figure 5]. To remove endosteal cortical bone, specific reamers are used. Berry et al.[76] found intraoperative femoral fractures commonly occur in uncemented total hip arthroplasty [Table 12].
Intraoperative—it is classified as
- Type A—proximal metaphyseal region
- A1—perforation—treated by morselized bone graft
- A2—undisplaced crack-cerclage with or without bone graft
- A3—unstable fracture-diaphyseal fitting stem and cerclage
- Type B—diaphyseal region
- B1—proximal to stem tip?—If stable bone graft, if not check for stem if stem not stable go with long stem or strut graft.
- B2—undisplaced crack—stem stable?—If yes cerclage, if no bone stock go with longer stem and cerclage.
- B3—displaced fracture—if stem stable go with allograft cerclage, if stem not stable use longer stem and graft and cerclage.
- Type C—distal diaphyseal/metaphyseal.
- C1—perforation—bone graft.
- C2—undisplaced crack—cerclage/strut.
- C3—displaced distal fracture—ORIF.
Postoperative
The Vancouver classification is
- Type A involves the trochanteric region—Greater trochanter or lesser trochanter.
- Type B is the most common type. Fracture occurs at prosthesis tip or just distal to it.
- B1—stem fixed well
- B2—stem loose
- B3—stem loose and proximal femur-deficient type C well below the tip of femoral prosthesis
During uncemented total hip arthroplasty, if femoral fracture is encountered, exposure should be done till the end of fracture is [Figure 6] seen. Then, the implant removed.[48] Cerclage wires have to be applied around the fracture site. Wires should be placed distal to the fracture so that further extension can be prevented. Then, trial broaching has to be done.[49] Implant reinserted and tension increases in the wires which prevent further displacement of stem. | Figure 6: (a) Postop X-ray left hip. (b) Patient had history of fall on the 10th day and developed Vancouver B3 type periprosthetic fracture. (c) Revised femoral stem with uncemented distal fitting long stem with cable support
Click here to view |
Fractures can occur after few months or years. Mcelfresh and Coventry described a classification for these fractures.
- Stress fractures due to overusage.
- Fractures due to stress risers include other implants.
- Fractures due to violent trauma.
The risk factors are heterotopic ossification and osteolysis and stem loosening. Duncan and Masri[77] described classification covers location and fixation of stem and the availability of bone stock.
Acetabular fracture
Though it is rare, posterior wall fracture is the common site, most commonly occurs in uncemented total hip arthroplasty. Davidson et al.[78] described the classification for acetabular fracture.
- Type I—undisplaced and stable cup.
- Type II—undisplaced and unstable due to specific fracture pattern.
- Type III—displaced and requires fixation.
After fixation of acetabular fracture, stability should be checked.[50] If cup is found stable, cement-less cup with augmentation screws is inserted. If cup is found unstable augmentation with antiprotrusio cage should be done. Acetabular fracture occurring after 6 weeks should be treated with fixation and antiprotrusio cage. In some cases, revision total hip arthroplasty is required.
Sciatic, obturator, femoral, peroneal nerves are injured during traction, extremity positioning, and pressure from retractors or by direct trauma. The risk factors are dysplastic [Figure 7] hip, revision surgery, arthritis, female sex, uncemented fixation, and limb lengthening. Risk of sciatic nerve injury is more in revision procedures because the nerve can be caught in scar tissue. Insertion of transacetabular screw in the danger zone may damage the nerves. Injury to sciatic nerve can be by prevented a careful dissection in dysplastic hip and revision surgeries. | Figure 7: Posterosuperior defect was constructed with graft from femoral head was provision fixed with k wires and reamed to give shape of augment
Click here to view |
Edwards et al.[1],[2] found in his study that limb lengthening of 1.9 to 3.7 is associated with peroneal nerve palsy. Sciatic nerve palsy occurs when lengthening of about 4–5 cm. Nercessian et al. found that in his study, laceration is only cause rather than lengthening. Eggli et al. in his study found no correlation found between limb lengthening and sciatic nerve palsy. Several studies described postoperative sciatic nerve palsy can be recovered by reducing the lengthening achieved.
Once sciatic nerve palsy developed, physiotherapy and foot drop stop splints are given.[44] Late exploration after 6 weeks is indicated for some cases. CT to be taken to know the position of screws and cement mass compresses the sciatic nerve. Complete recovery is not common and some residual deficit is expected.
Femoral nerve injury can occur but not common and can be injured in lateral approach where nerve compressed by retractors used for during anterior capsule reflection and compression by protruding cement. Obturator nerve and superior gluteal nerve are other nerves in danger.[45]
It is the commonest cause of death during in first 3-month postoperative period. Prevention can be done with mechanical and chemical methods. Early ambulation and pneumatic pump devices are advised as mechanical methods for the prevention of DVT. Pharmacological methods include use of warfarin, low molecular wt heparin (LMWH), fondaparinaux, aspirin, enoxaparin. Enoxaparin is commonly used.[46] Monitoring of international normalised ratio levels, platelets count, activated partial thromboplastin clotting time are needed in these situations.[48] Epidural hematoma can occur when enoxaparin is used with other toxic anesthetic drugs. ACCP has given guidelines[1] for thromboembolism prophylaxis and suggested LMWH, fondaparinaux, and vitamin K antagonist; one of them can be used as anticoagulant in special situations. When risk of bleeding is present, mechanical methods used first are followed by the use of chemical methods.[49]
ACCP suggested LMWH or warfarin along with mechanical compression devices postoperatively for 10–14 days. Aspirin continued for 4 weeks thereafter. For high-risk patients, LMWH or warfarin are given for 4–6 weeks postoperatively.
Subluxation or dislocation is due to the presence of the following risk factors:
- a) Revision surgery
- b) Faulty position and version of the components
- c) Femur impingement on pelvis or presence of residual osteophytes
- d) Weak abductor muscle
- e) Inadequate tension of soft tissue around hip
- f) Nonunion or avulsion of greater trochanter
- g) Posterior surgical approach
- h) Strenuous physical activity in the immediate postoperative period
Alberton et al.[1] found that the chance of getting postoperative dislocation is more after excessive soft tissue resection and using a small diameter femoral head and absence of muscle strength. Berry et al. found that surgical approach used influences the outcome of surgery.[50] They reported postoperative dislocation commonly occurs with posterior approach because of difficulty in position of the acetabular cup in the correct version.[51] While going through the posterior approach, methods of preventing postoperative dislocation should be carried out [Figure 8]. These are repair of short external rotators and posterior capsule. Posterior approach can be avoided in surgery for patients with muscular weakness and flexion contractures. | Figure 8: Intraop clinical picture showing femur head used augment to create concentric cup by decreasing defect then cup was lateralized and center of rotation was brought near to normal by impaction bone grafting
Click here to view |
Acetabular cup should be correctly positioned in correct ante-version and inclination to prevent postoperative dislocation.[61]
Orientation of patient pelvis to sagittal and coronal plane is assessed correctly by placing the patient in true lateral position.[62] In obese female patients, there is a tendency to place the cup in horizontal plane. In thin male patients, there is a tendency to place the cup in more vertical position. To prevent placing the acetabular cup in malposition, the following methods are used. These are fixing the patient stable in true lateral position, optimal exposure to see the bony landmarks, and using anterior–superior iliac spine for guide the position of pelvis.
Lewinnek et al.[79] described an array of the angle of inclination and ante-version in which dislocation chances are less. These include 40° ± 10° for angle of inclination and 15° ± 10° for ante-version. If the cup placed in more vertical, superior dislocation may occur during adduction. If the cup is placed in more horizontal, posterior dislocation may occur on flexion.[63] In retroverted cup, posterior dislocation occurs on adduction. In excessive anteverted cup, the femoral head dislocates anteriorly.
Impingement due to protruding bone cement, protruding implant due to incorrect version, remaining osteophytes, and malunion of greater trochanter can cause dislocation.[64] These prominences around implant act as fulcrum by which the implant gets dislocated. Consideration of femoral head size is important in preventing the hip dislocation. Compared to smaller head and head with skirted component, larger diameter head and nonskirted component is more stable. “Jumping distance” is more for larger diameter head, so impingement[65] range of motion is more for larger diameter head.
Postoperative instructions such as avoidance of extremes of position, positions prone for dislocation, are given to the patient and all attending personnel. Precautions measure can vary according to surgical approach used and other factors.[66] Noncompliance to precautions measure is ©the commonest cause of dislocation in the early postoperative period. Late postoperative dislocation is due to impingent which needs surgical revision.
Dislocation is suspected if patients give symptoms of abnormally rotated limb and pain and limb length discrepancy.[67] Immediate radiographs have to be taken. Once dislocation is confirmed, gentle traction along with slight abduction and specific maneuver have to be done. If patients present after 3 h, general anesthesia may need. The use of image intensifier is valuable in reducing dislocation. During reduction, the polyethylene component may be separated from its original position so incongruous alignment between head and acetabular cup seen in radiographs. In these situations, open reduction is needed.[68] If reduction is satisfied, immobilization for a period of about 6 weeks to 12 weeks with abduction splint is essential. Investigation has to be done to diagnose the above-mentioned causes. Surgical treatment like removal of remaining osteophytes, using elevated acetabular rim, exchanging the appropriate femoral head component is needed in some cases. If abductor muscle paralysis is the cause for dislocation, total hip arthroplasty is exchanged with bipolar hemi-arthroplasty.[69] In some cases, constrained acetabular socket is used as a last option. As a last option, total hip arthroplasty should be avoided in noncompliant patients.[70]
Kasetti et al.[47] conducted an exclusive study that is heterotropic ossification following total hip arthroplasty. In his study, none of the patients had any recognized risk factors for heterotopic ossification, and none of the patients had any pharmacological or radiotherapeutic prophylaxis against heterotopic ossification. He also noted a negative correlation[52] between the prevalence of heterotopic ossification and postoperative Harris Hip Score [Figure 9]. The incidence and severity of heterotopic ossification in anterolateral approach is found to be higher than the posterior approach. | Figure 9: Above intraop photos show flattening of femoral head; we used femoral head as graft
Click here to view |
It occurs from a mild form in the region of abductors to bony ankylosis. The increased risk is seen in patients with ankylosing spondylitis, Paget’s diseases, and other immune disorders.[71]
Anterior and anterolateral approach is related to heterotopic ossification.[72] Cement-less fixation is also related to heterotopic ossification formation. These lesions are visible on X-ray after 3–4 weeks of surgery.
Brooker et al.[80] classify extent of lesion:
- Grade I—presence of islands of bone.
- Grade II—presence of bone spikes in proximal femur and 1 cm of space between opposing bone surfaces.
- Grade III—bone spikes with less than 1 cm space between opposing bone surfaces.
- Grade IV—ankylosis
Patients present with symptoms of pain and restriction of motion.
[Table 13] Limb lengthening is common and is due to using long neck prosthesis or due to inadequate resection of neck or failure to restore the vertical offset. Lengthening >1 cm gives discomfort to the patient. Lengthening of >2.5 cm is associated with sciatic nerve palsy and limping.[1] Contracture release and bony correction is needed in some cases. Correct preoperative planning is essential.[73]
Several clinical intraoperative methods have been described. Shuck test is performed by giving traction when limb in extension.[74] Usually, release of about 2–4 mm occurs. It is subject to vary in some situations. Both femoral offset and vertical offset should be taken into consideration. In some cases, soft tissue tension may be restored with the help of overlengthening of limb only. So preoperative planning should be done for obtaining the soft tissue tension without overlengthening.[75]
The reliable method is the combined use of preoperative planning and intraoperative measurement.[1] Intraoperative methods include measuring the distance between pin placed in the infracotyloid area and tip of the greater trochanter. In bilateral hip disease, limb length is assessed in a stable hip. The use of same implants on both sides and same amount of resection is essential. Shortening produces instability that prone for dislocation. Limb length discrepancy of about 1 cm can be tolerated well.
Unacceptable discrepancy has to be investigated and correction treatment is needed. Acetabular cup-placed inferior to the tear drop and abnormal version has to be corrected in some cases.
It is a disabling complication and removal of implant is needed in deep-seated infection. [Table 14] The risk of infection is more in patients with diabetes mellitus, rheumatoid arthritis, and other immunodeficiency conditions. Patients with revision procedure, prolonged surgery time, hematoma formed also one of the risk factor.
Mechanism of bacterial infection:
- 1) Directroute
- 2) Indirect route from local wound
- 3) Hematogenous spread from distant site
- 4) Reactivation of dormant infection
Safe surgical techniques include use of double gloves, special gowns, limiting traffic[54] in the operative room, laminar flow systems, gentle handling of tissues.
Tsukayama classified periprosthetic infection into[1],[2]
- Early postoperative: occur within 1st month
- Late chronic infection: occur after one month
- Acute hematogenous infection: occur after 1 month from a distant source of infection
- Positive intraoperative culture diagnosis of infection
Patients give history of continuing pain, fever, wound discharge, swelling in spite of medical treatment. On examination, there will be pain with movements, sinuses, and erythema. Radiographs show features suggestive of loosening [Table 15]. Progressive loosening and periosteal reaction on radiographs, pseudobursae in arthrography of hip suggest infection. Blood investigation reveals elevated erthrocyte sedimentation rate (ESR), CRP. ESR >30 mm/h and CRP >10 mg/dl are indicative of infection. It takes a year for ESR and 3 weeks for CRP to return back to normal level. Aspiration can be done under anesthesia with fluoroscopy guidance to identify the organism.[55] Eighteen-ga needle is inserted at a mark just lateral to femoral vessels or the needle can be inserted laterally just above the greater trochanter tip. Aspirate is sent for cell count and culture sensitivity. The diagnosis of infection is made with elevated ESR, CRP levels along with aspirate WBC count 3800 cells/ml.
Reconstruction after infection
Before considering arthroplasty after infection following factors have to be taken into account.[56] These are functional status of the patient, eradication of infection, and adequate debridement. The next step in planning is when to do the reimplantation. Some suggest revision can be done at time of debridement, while others suggest that it can be done as second-stage procedure. Jackson et al.[81] reported 84% success rate for a single-stage procedure. Here implants are used with appropriate sensitive antibiotic mixed with cement is used. Success is influenced by patient general condition, sensitivity of organism to antibiotics in cement.
The advantages of two-stage procedures are follows:
- 1) Complete debridement is safeguarded.
- 2) Eradication of microorganism with antibiotics is attempted.
- 3) Source of infection can be identified and cleared.
- 4) Sufficient time to diagnose source of infection.
The disadvantages are:
- 1) Long period of hospital stay and disability
- 2) Economic problems
- 3) Delay in rehabilitation
In two stages, reimplantation antibiotics are given for 8–10 weeks after initial debridement. Revision arthroplasty is performed after 12 weeks if ESR, CRP is not elevated and aspiration of hip not showing any organism. Difficulties are encountered due to adhesion and scar tissue and osteoporosis. Trochanter nonunion, sciatic nerve palsy, limb length discrepancy, postoperative dislocations are expected complications.[58] Here acetabulum will be shallow and posterior wall is thinned so it is difficult to identify. The chance of getting ascetabulum fracture is more. Femoral canal preparation will be difficult because of osteoporosis. Fractures are expected and prophylactic cerclage wiring has to be done. If eradication of sepsis is doubted frozen section of biopsy material has to be done. If infection is present, revision arthroplasty is postponed for another 6 weeks. Recurrence of infection after revision surgery results in poor outcome. Though resection arthroplasty is used for eradication of infection, it is associated with poor functional outcome.[59]
It is commonly seen in cemented total arthroplasty and is called cement disease. It is a host reaction to particles produced. The mechanism of osteolysis:
- Particles production
- Migration particles into periprosthetic region
- Cellular reaction
The functional outcome is assessed in our study by using the modified Harris Hip Score. Harris Hip Score is a preoperative and postoperative scoring system designed to assess patient improvement, both objectively and subjectively.
In most of the Western studies like Schramm et al., Aldinger et al., Siebold et al., Harris Hip Score is used to assess the functional outcome.
Knahr et al.[38] considered Harris Hip Score as the best mean of objective evaluation of result of total hip arthroplasty.
- - Uncemented total hip arthroplasty to our patients in this study has given encouraging results.
- - The short-term results of this study show that the noncompliance of the patients during follow-up is a significant deciding factor in the functional outcome.
- - Our study also shows that the lowest preoperative Harris Hip Score generally results in poor functional outcome.
Ethical approval
This article does not contain any studies with human participants or animals performed by any of the authors.
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
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15], [Figure 16], [Figure 17], [Figure 18], [Figure 19], [Figure 20], [Figure 21]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12], [Table 13], [Table 14], [Table 15], [Table 16], [Table 17], [Table 18], [Table 19], [Table 20], [Table 21], [Table 22], [Table 23], [Table 24], [Table 25], [Table 26], [Table 27], [Table 28], [Table 29]
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