Introduction

Femoral neck fractures are common in the geriatric population and are associated with high morbidity and mortality. The worldwide incidence of hip fractures is expected to approach 6.26 million by 2050 (Kannus et al., 1996).

The optimal treatment for femorl neck fracture is a matter of debate for many years (Su, Aharonoff, Hiebert, Zuckerman, & Koval, 2003). In the past it was assumed that internal fixation was gold standard treatment for femoral neck fracture arguing that retaining the femoral head always gives the good results than the prosthetic replacement (Tidermark, Ponzer, Svensson, Söderqvist, & Törnkvist, 2003).

Treatment options for femoral neck fracture include closed reduction and internal fixation, hemi-arthroplasty include unipolar or bipolar arthroplasty and total hip arhroplasty (Mouzopoulos et al., 2008).Treatment by closed reduction and internal fixation is influenced by many factors like age of patient, displacement of fracture, quality of bone, delay in treatment, quality of fracture reduction, type of fixation devices and final position of the fracture. This method of treatment however gives high rate of non-union and avascular necrosis so that patients are ultimately landed into the revision sugery (Tidermark et al., 2003).

The majority of patients treated with hemi-arthroplasty developed the degeneration of acetabular cartilage by erosion of the prosthesis which may sooner require the revision surgery. The incidence is even higher in young patients and overall revision rate is 7 to 12% within a few years (Hedbeck et al., 2011).

Studies showed that the functional outcome and pain scoring improved in cases of femoral neck fracture treated by total hip arthroplasty than any other methods (Kyle, 2010).

Materials and Methods

This study was performed on 18 patients presented with history of fracture neck femur who were admitted to orthopedic department, Zagazig university hospital in the period between January 2019 to December 2019. All cases in this prospective study were treated by THA.

Prior to commencing the study, ethical clearance was taken from the Zagazig University hospitals and informed consent was obtained from all patients and their guardians before participation in the study.

Inclusion criteria

• Management of fractures neck femur in older active patients is controversial as THR is more predictable pain relief and better functional outcome than hemiarthroplasty.

• Both genders will be included.

• Fracture neck femur accompanied by other hip diseases as systemic lupus erythematosus, rheumatoid diseases and ankylosing spondylitis due to hip osteoarthritis.

• Old fracture neck femur after failed other fixation as cannulated screws, DHS and intra medullary nails that are used for fixation neck femur fracture associated with mid shaft femur fracture as femoral gamma nail and femoral recon nail.

• Neglected neck femur fracture.

• Patients 18 years old or more.

Exclusion criteria

• Patients with any active focus infection.

• Patients less than 18 years old.

• Multiple trauma patients with other surgical injuries.

• Medically unfit patients or those with extremely bad general condition who can't undergo anesthesia and surgery in general.

• Severe soft tissue problems at area of surgical approach as burn, necrosis and acute infection.

• Patients refused to participate.

This thesis performed upon 18 hips in 18 cases with fracture neck femur. The study was performed on the left side of 10 cases and right side of 8 cases.

Preoperative and operative steps

History

Sheet was taken for every case including: Name, age, sex, address, complaint, side, onset, progression of

Clinical Examination

General examination was done to exclude other metabolic, conge-nital or developmental causes.

Back examination

To exclude back as a source of pain or as associated back disorder.

Local examination including

site of hip pain, range of movement, leg-length discrepancy using blocks and rotational deformity.

• Back examination: to exclude back as a source of pain or as associated back disorder.

• Local examination including

site of hip pain, range of movement, leg-length discrepancy using blocks and rotational deformity.

Full laboratory pre-operative evaluation including

• Complete blood count.

• PT, PTT, INR.

• Random blood sugar.

• Liver and kidney function tests.

• Complete urine analysis.

• E.S.R, C.R.P

• Hepatic viruses HCV and HBV.

• HIV virus.

• Blood type.

Preoperative planning

Preoperative planning by plastic overlay templates supplied by the prosthesis manufacturer can shorten the operative time by eliminating repetition of steps. The wide array of implant sizes and femoral neck lengths allows precise fitting to the patient.

Surgical technique

Anesthesia

Spinal or epidural anesthesia was given.

Surgical position

Positioning the patient in a dead lateral position by using side supports of operating table with support in between legs (Figure 1).

Step (1)-Surgical approach

Hardinge direct lateral approach in lateral position was used. A muscle-splitting incision through the gluteus medius and minimus allows anterior dislocation of the hip and provides excellent acetabular exposure. Residual abductor weakness and limp after this approach was avoided by identifying gluteus medius muscle which is divided at its lower third and stay sutures for gluteus medius and minimus during approach for hip arthroplasty which is later approximated at the end of surgery.

The capsule is incised transversely and the femoral head is visualized. The head is dislocated helped by the assistant by flexion, adduction and external hip rotation and an oscillating saw is used to transect the femoral head. At first, preservative cut as possible later on, cut could be revised by calcar reamer. The head is then removed with a corkscrew. After removal of the head, a complete capsulotomy is performed, and visualization of the acetabulum is maximized by placing Homan retractors anteromedially and posterolaterally

STEP (2)-Preparation of the acetabulum

Excision of the labrum and if necessary, remove extensive osteophytes to visualize the entire acetabular rim. Landmarks of the acetabulum, such as the true floor and the transverse acetabular ligament are necessary for optimal placement of the cup.

Successive size reamers (reaming in 1mm increments) are used to ream to the ideal acetabular size without excessive thinning of the walls.

Reaming start close to the transverse acetabular ligament 45 degree from horizontal plane and 10-15 degree anteversion. The assessment of the reamed cavity should always be made with the trials. There must be a firm fit when fully seated in the acetabulum. It is important to inspect the anterior wall and remove any extended anterior wall beyond the rim of the acetabular component to avoid impingement. Acetabular trial handle is used to hold the selected sizing trial and positioned carefully and impacted into the acetabulum and checked to be stable press-fit.

We use the alignment rod with the pelvis oriented in the true lateral position, should be horizontal and in line with the trunk. Remove the trial and insert the definitive cup which should be stable then test for stability and range of motion after femoral preparation. Cup impaction with several firm hammer blows until fully seated when change in impact tone is heard. We try to gently rock the pelvis with the cup introducer to check for cup press-fit. Also cup can be fixed with screws which should be directed towards the posterosuperior or posteroinferior quadrants which are the safe zones of the acetabulum.

Now, we check for any prominent osteophytes which may cause impingement later on. Also, we can take fluoroscopic image to check for cup orientation (Figure 2).

STEP (3)-Preparation of the femur

Preparing the femur for the femoral stem by gradual ascending reaming. Do not implant the final stem but leave the trial stem/rasp in its final position for the trial reduction and cup alignment procedures. Inserting the femoral stem trial neck with the stem trial/rasp in its final position in the prepared femur, attach the desired trial neck. The appropriate trial head matching the cup bore size inserted fully in the trial neck length collar. Trial reduction followed by assessment range of motion, stability, impingement and leg length. Change the neck trial model if required to achieve correct soft tissue tension and repeat the procedure. Now, we can take fluoroscopic image to check for cup and stem position. Remove all trial components and implant the definitive stem implant. Then trial again with appropriate neck and head trial model. The definitive head is placed over the neck sleeve and press down firmly until resistance is felt. It is essential that the head is not tilted or placed at an angle on the sleeve to ensure proper seating.

Flush the entire joint with saline, cleaning and inspecting the articulating surfaces. Reduce the hip, taking great care to avoid either scraping the head along the cup rim, or allowing impact between the articular components. Finally, re-assess range of motion, stability and leg length (Figure 3).

This Table 1 shows that, the 55.6 % of studied group complained from left side lesion and 44.4 % complained from right side lesion. Also, table shows that 66.7 % of studied group had history of previous fixation. Previous operative fixation for fracture N F were 50 % Cannulated screw, 25 % DHS and 25% IMN. Regarding cause of lesion most frequent were failure of other fixation for N F fracture (66.7%) then acute fracture N F associated with OA (22.2%) and neglected N F fracture (11.1%).

This Table 2 shows that (66.6%) of studied group had Secondary osteoarthritis hip followed by (11.1%) had unilateral avascular necrosis of femur head then (16.6%) had X-ray manifestation of Ankloysing spondylitis and lastly (5.5) % of studied group had Systemic lupus with destructive erosion of hip.

Post operative X-ray finding of studied group

Position

Acetabulum

According to angle of inclination, 12 cases 66.6% were registered 45 degree, 4 cases 22.22% were registered 50 degree and 2 cases 11.1% were registered 40 degree.

Femur

16 case 88.88% were registered central stem position, one case 6.25% was registered varus stem position and one case 6.25% was registered valgus stem position.

DeLee and Charnley zones of the hip are distinct zones used in assessment of aseptic loosening in THR and there is no translucent line is registered in our study.

This Table 3 shows that all studied group had pain which is trigger for seeking medical advice and (77.8%) had limited mobility, then (16.7 %) had limping and the same percent enabled to weight bear. Lastly (11.1 %) of the participants studied sample had tenderness.

This Table 4 shows that 11.1% had post- operative superficial infection and the same percent had post-operative hip dislocation. Lastly 5.6% of the studied group had early deep infection and the same percent of the studied group had DVT.

This Table 7 shows that pre-operative mean± SD Harris score for studied group was 31.6±15.8 with range (13-71). While post- operative Harris score for studied group was increase to 89.5±5.2 with range (82-97). Difference statistically significant p<0.05.

This Table 8 shows that pre-operative Harris grade for studied group was 94.4 % poor and 5.6 % of them had fair Harris grade. While post operative Harris grade for studied group was 44.4 % good and 55.6% of them had excellent Harris grade. Difference statistically significant p<0.05.

Discussion

Hip fracture is an established public health concern globally owing to longer life expectancy, improvements in medical technology and increased vehicular traffic accident-associated with bone fractures (Gao, Liu, Xing, & Gong, 2012).

On reviewing underline causes of NF fracture, researcher found that 66.7 % of studied patients had previous fixation for NF femur. Previous methods of fixation were 50 % Cannulated screws, 25 % DHS and 25% IMN. Dissimilarity with Norwegian Arthroplasty Registry was reviewed by (Gjertsen et al., 2007) defined that 96% of the patients in whom THA was performed after failed internal fixation.

In present study underlying cause of NF fracture of studied group was 4/ 18 (22.2%) due to acute NF fracture associated with OA. Difference with (Dung, Trung, Quang, Hoang, & Van, 2017) who defined that THA was operated to 86.7% of patients due to osteoporosis situation. One of etiology of THA in present study was neglected N F fracture represented among (11.1%) of patients.

According to Post - operative complications of THA, our current study defined that 11.1% of follow up patients had post- operative superficial infection and 5.6% of the studied group had early deep infection as same as (Rogmark & Leonardsson, 2016) who declared the most common complications after fracture THA was infection.

Our current study showing that 8.3% of patients who done THA after previous failed internal fixation was suffered from post- operative superficial infection. Also, our current study showing that patients of neglected NF fracture had no infection. Similar to (Mahmoud, Pearse, Smith, & Hing, 2016) who declared that there are significantly more risk of complications in patients with salvage THA following failed internal fixation compared to primary total hip replacement for NF fracture. While, (Sassoon, D’apuzzo, Sems, Cass, & Mabry, 2013) who analyzed hospital complication rates found that infection occurred in 1.7% of NF fracture patients.

Our current study showing that 11.1% of whole patients who done THA suffered from post-operative hip dislocation. Disagreement with meta-analysis reported dislocation rate was 6.9% following THA for NF fracture (Bhandari et al., 2003; Sassoon et al., 2013) who analyzed hospital complication rates found that acute dislocation occurred in 0.14% of NF fracture patients. Disagreement with (Ismail, Khaled, El-Nahal, & El-Geady, 2017) determined postoperative dislocation was 2.5% among elderly patients with NF fracture managed by THA at 2-year follow-up.

Heterogeneity of dislocation rate explained through various factors influence that increasing the risk of dislocation after THA including factors such as age, sex, diagnosis, dementia, neuromuscular and cognitive disorders or surgical risk factors such as surgical approach, component positioning, soft tissue tension and head size (Khatod, Barber, Paxton, Namba, & Fithian, 2006).

Patients with NF fracture undergoing THA have a higher rate of dislocation that is possibly due to relative laxity of the hip capsule, violation of the hip capsule during the acute injury and poor compliance for medical advices of elderly patients population (Hongisto et al., 1998).

Our current study showing that 22.22% from whole group had complication after THA who suffered from failed internal fixation of NF fracture compared to11.11% from whole group who had complication after THA who suffered from acutely NF fracture. While (Stafford, Charman, Borroff, Newell, & Tucker, 2012) declared that THA for treatment of acute NF fracture gives comparable results with other indications for THA.

(Mckinley & Robinson, 2002) compared patients treated for failed internal fixation of NF fracture with an age and sex-matched group who had undergone THA acutely for NF fracture. They found significantly more early complications, a higher revision rate at 5 to 10 years and inferior functional outcomes in those treated for failed internal fixation when compared with those treated acutely.

Our study defined the incidence of DVT was 5.6% among whole patients managed via THA who had failed NF fracture fixation. Agreement with a prospective study was conducted by (Jain, 2004) in India on 60 NF fracture hip in 45 patients who underwent THA without any known risk factors for thromboembolic disease. DVT was studied by serial color Doppler ultrasonography. DVT was found in 3.3% of patients who had undergone THA. Dissimilar to (Fujita et al., 2000) who detected DVT in 22.6% of 164 patients undergoing THA.

Regarding improvement quality of life, the present study clarified that NF fracture patients managed by the pre-operative mean HHS for studied group was 31.68 with range 13-71. Raising up post- operative to be 89.5 with range 82-97 with the difference statistically significant. Consistence with (Rudelli, Viriato, Meireles, & Frederico, 2012) who reported excellent functional outcomes and up to 90% of patients returning to their pre-injury activity levels following THA. One the same line a large cohort study found patients had NF femur treated with THA had a lower level of pain and a higher level of satisfaction (Leonardsson et al., 2013).

In present study, pre-operative HHS grade for studied group was 94.4 % poor and 5.6 % of them had fair Harris grade. While post -operative HHS grade for studied group was 44.4 % good and 55.6% of them had excellent HHS grade with Difference statistically significant. Similar study was done on outcome of THA for NF femur found that HHS excellent 40%, good, 45% and fair 15% size (Khatod et al., 2006).

Consistence with (Tuteja, Mansukhani, & Mukhi, 2014) defined that; HHS at the end of 6 months was excellent for 19%, good for 66.7% and fair for 14.3%. More over patients managed by THA 75% able to do daily activity. Concerning pain level; 76.2% of patients had no pain, 19% of them suffered from slight pain and 4.8% reported mild pain at end of 6 months follow up. Agreement with (Katchy, Katchy, Ekwedigwe, & Ezeobi, 2018) who determined pre-operative HHS was 44.65 ± 5.91 while after one year post- operative improvement of HHS to be 88.52± 5.56.

Consistence with (Mingli et al., 2017) who defined the mean HHS of the patients were 47 and 85 before and after THA, respectively. The rate of excellent and good results is 82.7%. The difference between pre and post-operation HHS was statistically significant.

(Ismail et al., 2017) evaluated hip function by HHS. Scoring of the 40 patients was done at 6weeks, 3months, 6 months and every 6 months thereafter. At 6weeks, the mean HHS was 84 and Harris grade is good, at 6months, the mean HHS was 90.5 and at end of follow up period, HHS was 94.

In present study found mean HHS was 35 pre –operative in patients with failed internal fixation of NF fracture and Post-operative THA mean HHS was 88.9. Compared to pre-operative in patients who had acutely NF fracture, HHS was 19.5 and raised up Post-operatively to be HHS 91. Consistence to study (Mckinley et al., 2002) who declared that patients with failed internal fixation of NF fracture and patients who had acutely NF fracture with an age and sex-matched group undergone THA. They found significantly more early complications and inferior functional outcomes in those treated for failed internal fixation NF fractures.

One the same line, study found mean HHS post THA for Failed Internal Fixation of NF fracture was 81.8 at 2-years follow-up period (Archibeck, Carothers, Tripuraneni, & White, 2013).

(Dung et al., 2017) declared Cementless THA with minimally invasive surgery for NF fracture have 93.3% good and excellent results.

From above finding, it is evidence that THA is globally improve the total quality of life.

In pain studying following THA, our present study estimated Harris pain score was preoperatively 8.3± 9.2(0-30) improved post- operatively to be 37.9± 6.6 (30-44) similar to (Park, Oh, & Yoon, 2013) who estimated Harris pain score post-operative to be 40.65± 3.6.

In limping studying following THA, our present study estimated Harris limping score was preoperatively 4.8± 1.9(2-8) improved post- operatively to be 10± 1.5 (8-11) similar to (Pongcharoen & Chaichubut, 2019) who estimated Harris limping score after one year THA via direct lateral approach to be 10.66 ± 1.27 (5-11).

In range of motion studying following THA, our present study estimated Harris range of motion score was preoperatively 2.7± 1.6 (1-5) improved post- operatively to be 4.6± 0.5 (4-5). Agreement with (Park et al., 2013) who estimated Harris of motion score post-operatively to be 4.50± 0.73.

In deformity studying following THA, our present study estimated Harris deformity score preoperatively was 2.2±2(0-4) improved post- operatively to be 4± 0 (4-4) comparable to (Park et al., 2013) who estimated Harris deformity score post-operatively was 3.75± 1.9.

In walking studying following THA, our present study estimated Harris walking score preoperatively was 4.8±2.2 (2-11) improved post- operatively to be 10.2±1.4 (8-11). The same finding (Ismail et al., 2017) evaluated hip function by HHS. Scoring of the 40 patients was done at 6 weeks, 3months, 6months and every 6months thereafter. Showing improvement in limping and distance walked being unlimited.

Conclusions

NF fractures are common in the geriatric population and are associated with high morbidity and mortality. THR is one of the most successful orthopaedic surgical procedures and has regained popularity during the last few decades with minimal pain.

In all cases, NF fracture recent with OA hip, old neglected and old failed NF fracture fixation and all cases managed by THR (Zimmar Co.). We assessed the clinical signs and symptoms using Harris hip score, and radiological evaluations in pre and post-operatively.