Antero-lateral minimal invasive (ALMI) approach for total hip arthroplasty technique and early results

Is the Anterolateral or Posterolateral Approach More Effective for Early Postoperative Recovery after Minimally Invasive Total Hip Arthroplasty?

Currently, various minimally invasive surgical techniques are applied for total hip arthroplasty (THA). There are few studies comparing the early postoperative clinical outcomes of minimally invasive THA between anterolateral and posterolateral approaches. In this retrospective study, 62 patients underwent minimally invasive THA via either the anterolateral approach with an intermuscular exposure using the modified Watson-Jones approach (MIS-AL, 34 hips) or mini-incision THA with a posterolateral approach (MIS-PL, 28 hips). We analyzed intraoperative data, postoperative hematological data, postoperative radiographic findings, and the postoperative recovery of muscle strength. The mean surgical time was significantly longer in the MIS-PL than in the MIS-AL group. The mean postoperative serum C-reactive protein level was significantly higher in the MIS-PL group than in the MIS-AL group only on postoperative day 3. There were no significant between-group differences in the postoperative recovery rate of muscle strength during hip abduction. The recovery rate of muscle strength during hip extension was better in the MIS-AL group than in the MIS-PL group only on postoperative day 3. In conclusion, we found no obvious advantage in early postoperative recovery between the MIS-AL and MIS-PL approaches. Therefore, the benefit of rapid postoperative recovery was comparable between the MIS-AL and MIS-PL approaches.

Minimally invasive anterolateral approach versus lateral transmuscular approach for total hip arthroplasty: A systematic review and meta-analysis

BACKGROUND

Total hip arthroplasty (THA) using a minimally invasive (MI) approach is a commonly performed procedure, and several approaches are now being used clinically. The MI anterolateral (MIAL) approach is one of the MI approaches used in clinical practice. Whether the MIAL approach is superior to non-MI approaches remains controversial. To resolve this controversy, we performed a systematic review and a meta-analysis of results of THA procedures that used the MIAL approach. We assessed whether the MIAL approach was superior to the lateral transmuscular (LT) approach in terms of operative time, operative blood loss, radiological parameters, and clinical outcomes.

METHODS

We performed a methodical search for all literature published on PubMed, Web of Science, and the Cochrane Library, and pooled data using the RevMan software. A p value < 0.05 was considered statistically significant. We calculated the mean differences (MD) for continuous data with 95% confidence intervals (CI) for each outcome.

RESULTS

This meta-analysis included 6 studies. Pooled results indicated no statistically significant differences between the groups in terms of operative time (MD = 5.13, 95% CI -2.49 to 12.75, p = 0.19), cup abduction angle (MD = 1.64, 95% CI -1.32 to 4.60, p = 0.28), and cup anteversion angle (MD = 0.75, 95% CI -1.09 to 2.59, p = 0.43). Operative blood loss was significantly greater in those who underwent THA via the MIAL approach than those who underwent THA via the LT approach (MD = 68.01, 95% CI 14.69 to 121.33, p = 0.01). The postoperative Harris hip score (HHS) assessed at the time of final follow-up was significantly higher in those who underwent THA via the MIAL approach than those who underwent THA via the LT approach (MD = 1.41, 95% CI 0.50 to 2.33, p = 0.002).

CONCLUSION

We conclude that the MIAL approach is superior to the LT approach in terms of clinical outcomes.

LEVEL OF EVIDENCE

Level Ⅱ.

"Anterolateral" approach to the hip: a systematic review of the correct definition of terms

PURPOSE

The Watson-Jones interval plane between tensor fascia lata (TFL) and the gluteus medius (GM) has come back into fashion in the past few years - Röttinger described the anterolateral minimal invasive approach (ALMI) for use in total hip replacement, in which the standard Watson-Jones interval was used, but with a completely intermuscular plane. However, the term anterolateral is often still utilised to describe intramuscular approaches in which the GM was violated, thus creating a potential misunderstanding in the literature. Accordingly, we have designed a study to answer the following questions: (1) are there articles in the recent literature that use the term "anterolateral" to describe different approaches; (2) which would be the correct description of the anterolateral approach?

METHODS

We did a systematic review of the literature based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, to look for peer reviewed papers of any evidence level focusing on the definition of anterolateral approach; MEDLINE and EMBASE were searched.

RESULTS

73 manuscripts met the criteria of the systematic search. 53 papers (72.6%) reported the term anterolateral approach to describe a complete intermuscular approach between the interval between GM and TFL. Nonetheless, in the remaining 20 papers (27.4%) the term anterolateral was used to describe intramuscular approaches in which the gluteus medius was violated.

CONCLUSION

In about 1 out of 4 papers in the recent literature, the term anterolateral was utilised to describe approaches that are completely different both in terms of anatomy and function.

A comparison of leg length discrepancy between direct anterior and anterolateral approaches in total hip arthroplasty

Background

Leg length discrepancy (LLD) after total hip arthroplasty (THA) is a known source of complications and a leading cause of litigation (J Bone Joint Surg Br 87:155–157, 2005). There are limited studies investigating surgical approach combined with the use of fluoroscopy intraoperatively and their potential effects on LLD after THA. The purpose of this study was to compare the direct anterior (DA) approach utilizing a fluoroscopic overlay technique and anterolateral (AL) approach and their potential effect on LLD.

Methods

We retrospectively reviewed 121 patients who had undergone primary THA from September 1, 2016 to November 1, 2018 by either DA or AL approach by two separate surgeons. Leg length discrepancies were measured on pre-operative post-anesthesia care unit (PACU) and on post-operative low anterior/posterior (AP) pelvis plain radiographs by two investigators blinded to each other’s measurements. To confirm inter-observer and intra-observer reliability between LLD measurements amongst investigators, a Pearson correlation test was performed. The primary outcome measurement was leg length discrepancy (LLD).

Results

We observed LLD > 1.0 cm and LLD > 1.5 cm in the DA and AL groups. The DA approach group showed a mean LLD of 4.5 mm against 7.76 mm in the AL group (p < 0.00001). There was a significantly higher rate of LLD in the AL group as compared to the DA group (LLD> 1 cm (28% vs. 8%, p = 0.0037) and LLD > 1.5 cm (7% vs. 0%, p = 0.0096). The LLD measurements showed strong correlation in terms of inter-observer (r = 0.95) and intra-observer reliability (r = 0.99) between the two investigators (p < 0.001).

Conclusion

In our patient cohort, the DA approach with fluoroscopic overlay technique had less LLD in comparison with the AL approach, suggesting that intraoperative fluoroscopic use does have an impact on LLD.

Long-term results of an anatomically implanted hip arthroplasty with a short stem prosthesis (MiniHipTM)

AIM

To evaluate the clinical and radiological outcome nine and ten years after short-stemmed, bone preserving and anatomical hip arthroplasty with the MiniHip^TM system.

METHODS

In a prospective study, 186 patients underwent hip arthroplasty with a partial neck preserving short stem (MiniHip^TM, Corin). Elderly patients were not excluded from this study, thus the mean age at the time of surgery was 59.3 years (range 32 to 82 years). Surgery and the follow-up assessments were performed at two Centers. Up until now, the mean follow-up was 112.5 ± 8.2 mo. The Oxford Hip Score (OHS) and the Hip Dysfunction Osteoarthritis and Outcome Score (HOOS) was assessed pre- and each year after surgery. The clinical follow-up was accompanied by standardized a.p. and axial radiological examinations. Periprosthetic lucencies, hypertrophies within the Gruen zones one to fourteen were assessed. A subsidence of the stem was investigated according to Morray and heterotopic ossifications were assessed according to Brooker.

RESULTS

The OHS and HOOS improved from 18 ± 3.3 to 46 ± 2.0 and from 30 ± 8.3 to 95 ± 4.6 points, P < 0.001 respectively. There were no differences regarding age, etiology, friction pairings, etc., (P > 0.05). Two stems were revised due to a symptomatic subsidence four and twelve months postoperatively. Thus, the survivorship for aseptic loosening at nine to ten years was 98.66%. Including one stem revision due to a symptomatic exostosis, bursitis and thigh pain as well as one revision because of a septic stem loosening, the overall survival for the stem with revision for any reason was 97.32%. Besides one asymptomatic patient, radiological signs of a proximal stress-shielding, such as bone resorptions within the proximal Gruen zones, were not noticed. Findings suggesting a distal loading, e.g., bony hypertrophies or bone appositions of more than 2 mm, were also not detected.

CONCLUSION

Regarding these first long-term results on the MiniHip^TM, the implant performed exceedingly well with a high rate of survivorship for aseptic loosening. Our radiological results within the Gruen zones support the design rationale of the Minihip to provide a reliable metaphyseal anchoring with the expected proximal, more physiological load transfer. This might minimize or exclude a stress shielding which might be associated with thigh pain, proximal bone loss and an increased risk of aseptic loosening. The MiniHip^TM is a reliable partial-neck retaining prosthesis with good a clinical long-term outcome in younger as well as elderly patients.

Acetabular cup orientation and postoperative leg length discrepancy in patients undergoing elective total hip arthroplasty via a direct anterior and anterolateral approaches

Background

Total hip arthroplasty (THA) is considered a successful surgical procedure. It can be performed by several surgical approaches. Although the posterior and anterolateral approaches are the most common, there has been increased interest in the direct anterior approach. The goal of the present study is to compare postoperative leg length discrepancy and acetabular cup orientation among patients who underwent total hip arthroplasty through a direct anterior (DAA) and anterolateral (ALA) approaches.

Methods

The study included 172 patients undergoing an elective THA by a single surgeon at our institution within the study period. Ninety-eight arthroplasties were performed through the ALA and 74 arthroplasties through the DAA. Preoperative planning was performed for all patients. Assessment of the two groups included the following postoperative parameters: abduction angle, cup anteversion angle and leg length discrepancy (LLD). Additional analysis was done to evaluate component positioning by comparing deviation from the Lewinnek zone of safety in both approaches.

Results

For the DAA the absolute LLD was 11 mm, ranging from -6 mm to 5 mm. For the ALA, the absolute LLD was 36 mm, ranging from -22 mm to 14 mm. None of the DAA patients had an absolute LLD greater than 6 mm. Comparatively, 7.4% of the ALA group exceeded 6 mm of LLD in addition to 2.1% with LLD greater than 10 mm. 15% of the ALA group resided out of the Lewinnek abduction zone compared to 3% of the DAA group (P = 0.016). 17% of the ALA group were out of the Lewinnek anteversion zone as opposed to 8% of the DAA group (P = 0.094).

Conclusion

Our study demonstrates good component positioning outcomes and LLD values in patients following THA through the DAA compared to the ALA.

Influence of Surgical Approach on Pelvic Lift in Hip Arthroplasty During Cup Insertion

The position of the acetabular cup is a major factor in the long-term outcome of total hip arthroplasty (THA). Malpositioning of the acetabular cup frequently has been reported with the use of a minimally invasive implantation technique. It remains unclear whether the limited visibility or the increased retractor traction and thus tilting of the pelvis during cup implantation is the cause. This study investigated the influence of iatrogenically related pelvic lift using an anterolateral minimally invasive THA technique. In a group of 30 consecutive patients who underwent THA via a minimally invasive anterolateral approach, iatrogenic lifting of the pelvis was measured with a smartphone using a 3-axis accelerometer and compared with patients in a historical age- and sex-matched control group who underwent THA using a transgluteal approach. Postoperatively, the inclination and anteversion of the cup was determined on pelvic radiographs. In the anterolateral group, the pelvis was lifted by a maximum of 6.3° and by an average of 3.9° when the acetabular cup was impacted; no difference was noted compared with the transgluteal group. In contrast, the cups in the anterolateral group showed significantly increased inclination and reduced anteversion. In both techniques, the iatrogenic tilting of the pelvis at the time of cup implantation occurred to a comparable extent. Therefore, the significant differences in postoperative radiographs cannot be attributed to increased retractor traction on exposure of the acetabulum, which means that the limited visibility must be responsible. [Orthopedics. 2017; 40(4):e589-e593.].

Periprosthetic bone density changes after MiniHipTM cementless femoral short stem: one-year results of dual-energy X-ray absorptiometry study

Introduction: The purpose of the current study was to investigate the reaction of the femur to the implantation of the MiniHip^TM in terms of: (1) bone density change during one year; (2) correlations between stem length, CCD (caput-collum-diaphyseal), femoral offset, T-value, and bone density; (3) other co-variables that influence the change of bone density.

Patients and methods: MiniHip^TM implant was performed for 62 patients. The age range of the patients who underwent treatment was 25–78 years. Periprothestic bone density was determined within two weeks postoperatively, after three, six, and twelve months utilizing the DEXA scan.

Results: The highest change was observed in the first three months post-implantation, while significant decrease in density was recorded at proximal Gruen zones 1, 2, and 7, and at distal Gruen zone 4. The decrease in density reached a plateau between the third and sixth months after operation. Afterwards, bone density recovered up to the 12th postoperative month. The correlation analysis showed significant difference between Gruen zone 1 and stem size and CCD. The same significant trend was not reached for Gruen zone 7. Femoral offset showed no correlation. Covariance analysis was unable to establish connection of the results with diagnosis, pairings, or gender.

Discussion: MiniHip^TM densitometric results are promising and comparable to good results of the other representatives of the femoral neck partially-sustaining short stem prostheses with a lower proximal bone density reduction. Periprosthetic bone resorption is a multifactorial process where stem size, CCD angle, and patient-specific variables such as T-value have an impact on the periprosthetic bone remodeling. In particular, this applies to Gruen zone 1.

Modified anterolateral approach in minimally invasive total hip arthroplasty

PURPOSE OF THE STUDY

Minimally invasive procedures for total hip arthroplasty (THA) provide less surgery related trauma, and perhaps a fast recovery and satisfaction. Using modified instruments, we reported clinical follow-up data for a modified anterolateral approach.

BASIC PROCEDURES

Using specialised retractors to expose the acetabulum and femur, this single-incision technique preserved more gluteus medius tendon and provided access for soft tissue repair. The demographic data for 1003 patients undergoing THA with this technique are presented, including operative variables, complications, Harris Hip Score for clinical evaluation and cup inclination angle for radiographic evaluation. Average follow-up was 59 months (range 24-121).

MAIN FINDINGS

In 1077 primary THAs performed in 1003 patients, the median wound length was 6 cm (range 4.8-9.2), median operation time was 68 minutes (range 45-112). The mean perioperative blood loss was 422 mls (range 56-990). The median cup inclination angle was 44 degrees (range 33-54), median acetabular version angle was 17° (range 12-24) median length of hospitalisation was 4 days (range 3-8). A total of 22 (2.0%) complications were noted including 5 cases of stem subsidence, 4 cup loosening, 5 greater trochanter fractures, 4 infections, 2 intraoperative proximal femur fractures and 2 iliopsoas impingement. In total, 13 (1.2%) received additional surgery. No neurovascular injury or dislocation was noted. For the clinical results, Harris Hip Score improved from 53 (range 33-67) preoperatively to 94 postoperatively (range 87-100).

PRINCIPAL CONCLUSIONS

Minimally invasive surgery via this modified anterolateral approach is a safe and reliable method.

Anterior and Anterolateral Approaches for THA Are Associated With Lower Dislocation Risk Without Higher Revision Risk

BACKGROUND

Lack of consensus continues regarding the benefit of anteriorly based surgical approaches for primary total hip arthroplasty (THA). The purpose of this study was to evaluate the risk of aseptic revision, septic revision, and dislocations for various approaches used in primary THAs from a community-based healthcare organization.

QUESTIONS/PURPOSES

(1) What is the incidence of aseptic revision, septic revision, and dislocation for primary THA in a large community-based healthcare organization? (2) Does the risk of aseptic revision, septic revision, and dislocation vary by THA surgical approach?

METHODS

The Kaiser Permanente Total Joint Replacement Registry was used to identify primary THAs performed between April 1, 2001 and December 31, 2011. Endpoints were septic revisions, aseptic revisions, and dislocations. The exposure of interest was surgical approach (posterior, anterolateral, direct lateral, direct anterior). Patient, implant, surgeon, and hospital factors were evaluated as possible confounders. Survival analysis was performed with marginal multivariate Cox models. Hazard ratios (HRs) and 95% confidence intervals (CIs) are reported. A total of 42,438 primary THAs were available for analysis of revision outcomes and 22,237 for dislocation. Median followup was 3 years (interquartile range, 1-5 years). The registry's voluntary participation is 95%. The most commonly used approach was posterior (75%, N = 31,747) followed by anterolateral (10%, N = 4226), direct anterior (4%, N = 1851), and direct lateral (2%, N = 667).

RESULTS

During the study period 785 hips (2%) were revised for aseptic reasons, 213 (0.5%) for septic reasons, and 276 (1%) experienced a dislocation. The revision rate per 100 years of observation was 0.54 for aseptic revisions, 0.15 for septic revisions, and 0.58 for dislocations. There were no differences in adjusted risk of revision (either septic or aseptic) across the different THA approaches. However, the anterolateral approach (adjusted HR, 0.29; 95% CI, 0.13-0.63, p = 0.002) and direct anterior approach (adjusted HR, 0.44; 95% CI, 0.22-0.87, p = 0.017) had a lower risk of dislocation relative to the posterior approach. There were no differences in any of the outcomes when comparing the direct anterior approach with the anterolateral approach.

CONCLUSIONS

Anterior and anterolateral surgical approaches had the advantage of a lower risk of dislocation without increasing the risk of early revision.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Modified direct anterior approach in minimally invasive hip hemiarthroplasty in a geriatric population: a feasibility study and description of the technique

INTRODUCTION

The direct anterior approach (DAA) is generally accepted method for minimal invasive arthroplasty of the hip. As good results for total hip arthroplasty are already published, there is a lack of evidence for the implantation of bipolar hip hemiarthroplasty (BHH) in elderly patients with osteoporosis after femoral neck fracture.

MATERIALS AND METHODS

For hip arthroplasty using a direct anterior approach (DAA) in elderly patients with femoral neck fractures, a number of modifications of the original technique are being described. The modified DAA considers in particular the co-morbidity and the bone quality of the geriatric patient population. A consecutive series of 16 hemiarthroplasties using this technique is presented. In all 16 cases, the BHH was implanted in modified DAA technique. Mobility measured by 4-item Barthel Index, pain via visual analogue scale (VAS), duration of surgery, external length of incision and blood loss were evaluated.

RESULTS

There was no major operative complication during the procedures. The pain level decreased from 7 (preoperatively) to 0 at postoperative day 40. The Barthel Index increased from 5 at first postoperative day to 40 at day 40. Early postoperative mobilisation is efficiently accelerated. Mean operating time was 71 min; the medium skin incision length was 8 cm. The mean haemoglobin level decreased from 118 g/dl preoperatively to 101 g/dl at first postoperative day.

CONCLUSION

The described modifications of the DAA help to implant a BHH gently in elderly patients with increasing risk of complications like iatrogenic fractures, wound or prosthesis infections and haematoma. This will hopefully lead to a faster rehabilitation and lower mortality rate for patients with femoral neck fractures in the future.

The mini postero-postero-lateral mini incision in total hip arthroplasty

PURPOSE

Mini invasive incisions in THA and femoral hip prostheses tend to minimise healing and recovery time. We have used a very posterior approach with technical modifications and precise skin landmarks to decrease surgical complexity, and we describe this experience here.

METHODS

From 2010 to 2012, 140 patients aged 79 years (range 53-93 years) were operated upon by the same surgeon in a continuous series using the same minimally invasive skin incision and six different types of implants. The incision was very posterior in the hip allowing direct visualisation of the acetabulum in the hip flexion position and visualisation of the femoral shaft extremity in a leg flexion position.

RESULTS

The mean operating time was 100 minutes (range 75-110 min). Estimated blood loss was 385 cc (20-585 cc). Twenty-six patients had blood transfusion. The mean hospital stay was 6.8 days (5-20 days) including the time waiting for a rehabilitation centre. No operative complications related to the technique were recorded. On the postoperative radiograph, the femoral stem was aligned with the femoral axis within 3° in all patients. The mean acetabular angle to the ground plane was 40° (35-48°). No patient had a leg length discrepancy of more than four millimetres. The mean skin incision length was seven centimetres (six to eight centimetres). All patients were seen at the clinic after six weeks and the data were unchanged at this time point.

CONCLUSION

The method and skin landmarks we describe appear to be a safe way to perform minimally invasive total hip replacement.

Little clinical advantage of modified Watson-Jones approach over modified mini-incision direct lateral approach in primary total hip arthroplasty

This study compared the clinical outcomes of total hip arthroplasty using a minimally invasive anterolateral approach with a muscle-sparing technique (modified Watson-Jones approach) and the modified mini-incision direct lateral approach. We randomly assigned 102 patients to the muscle-sparing group (n = 52) or the mini-incision direct lateral group (n = 50). Muscle strength recovery of hip abduction at 6 weeks after surgery was better, and creatine kinase level at 1 day after surgery was lower in the muscle-sparing group than in the mini-incision direct lateral group (P < .01). However, there was no difference in the Harris hip score, pain visual analog scale, the Western Ontario and McMaster Universities Osteoarthritis Index, and Medical Outcomes Study Short Form 36 score between the 2 groups throughout the 1-year study period.

Differences in muscle trauma quantifiable in the laboratory between the minimally invasive anterolateral and transgluteal approach

INTRODUCTION

In Europe the minimized transgluteal (TG) and anterolateral (AL) approaches are increasingly preferred in hip arthroplasty (THA).

METHOD

The present investigation determined which of these approaches causes the least muscle trauma. Forty patients who received a THA were enrolled in this prospective randomized study. Muscle trauma was quantified by perioperatively measuring the serum concentration of skeletal troponin I (sTnI). The Harris hip score (HHS) was determined before and 12 months after surgery.

RESULTS

It increased significantly in all patients without being different between the groups (AL, 48.2→83.6; TG, 50.8→85.9). Patients in the TG group had a higher sTnI than those in the AL group 24 h postoperatively (21.6 vs. 10.9 nmol/ml, p = 0.022). The AL approach results in a reduced muscle traumatization compared with the TG approach, without this being revealed by the HHS.

Minimally invasive versus conventional exposure for total hip arthroplasty: a systematic review and meta-analysis of clinical and radiological outcomes

Over the past decade, minimally invasive surgery has gained popularity as a means of optimising early postoperative rehabilitation and increasing patient satisfaction and cosmesis following total hip arthroplasty (THA). However, this surgical exposure has also been associated with increased risk of iatrogenic nerve injury and implant mal-positioning due to limited visibility compared to conventionally larger surgical incisions. The purpose of this meta-analysis was to compare the outcomes of these two surgical exposures. A systematic review of the published and unpublished literature was conducted to include all randomised and non-randomised controlled trials comparing the clinical and radiological outcomes of minimally invasive and conventional THA procedures. In total, 28 studies met the eligibility criteria and included 2,849 hips, i.e. 1,428 minimally invasive compared to 1,421 conventional THAs. The meta-analysis of the current evidence base showed that minimally invasive THA is associated with a significantly increased risk of transient lateral femoral cutaneous nerve palsy (p = 0.006) with no significantly better outcome.

[Konzept Perioperative management for endoprosthetic hip joint replacement. The functional interdisciplinary therapy (FIT) concept]

During the last decade there have been significant changes in the perioperative management of total hip replacement patients. This process begins in the preoperative phase. Many patients are much better informed and standardized preoperative patient programs improve patient outcome and optimize the clinical pathways. The techniques in perioperative pain management have also significantly improved. The surgeon should not only rely on the anesthesiologist but should also use the options available during surgery. Postoperative weight bearing is handled in a much more progressive way than previously. In a standard primary hip replacement pain-adapted full weight bearing is possible if there are no patient-specific problems. There has also been a shift in the postoperative capability of performing athletic or recreational activities. In general patients can perform those activities that were performed before the surgery, which also includes, for example downhill skiing.

The anterolateral minimally invasive approach for total hip arthroplasty: technique, pitfalls, and way out

Different approaches for the hip have been developed for minimally invasive surgery in total hip arthroplasty. The goal of minimally invasive surgery is to reduce invasiveness to skin, muscles, and bone and improve recovery time after total hip arthroplasty. This article describes the technique of a minimally invasive approach to the hip from the anterolateral direction step by step and includes preoperative settings and pitfalls.

Anterolateral mini-invasive versus posterior mini-invasive approach for primary total hip replacement. Comparison of exposure and implant positioning

INTRODUCTION

We conducted a prospective study to compare the exposure and implant positioning in primary total hip replacement through the anterolateral minimally invasive (ALMI) approach versus the posterior minimally invasive (PMI) approach.

MATERIALS AND METHODS

We applied these techniques to 2 consecutive groups (33 and 43 patients, respectively) comparable preoperatively. All the patients received the same cementless stem and acetabular component.

RESULTS

There were neither significant difference in femoral or acetabular component positioning nor in limb-length discrepancy. Acetabular exposure was easy through the ALMI approach. Femoral exposure was more difficult as fractures of the trochanter and femoral perforation in our study show.

CONCLUSION

For us, exposure and implant positioning through the ALMI approach and the PMI approach are comparable and reliable. However, we recommend caution during the initial learning curve in osteoporotic patients due to the higher rate of peroperative complications for the ALMI approach.

THA performed using conventional and navigated tissue-preserving techniques

Less invasive methods of performing total hip arthroplasty have been considered controversial after increased complication rates and component malpositioning were reported. A new method of performing total hip arthroplasty through an incision in the superior capsule, posterior to the abductors and anterior to the posterior capsule, was developed with the aim of producing a technique that maintained the joint stability of the transgluteal exposure and the rapid abductor recovery of the posterior exposure. We assessed the recovery and complications of this technique performed with surgical navigation. The study group was compared with similar subjects who had conventional total hip arthroplasty, without surgical navigation, using the transgluteal exposure. There were 185 consecutive total hip arthroplasties in the study group and 189 nonconsecutive historical total hip arthroplasties in the control group. The two groups were controlled for complexity and had no differences in body mass index, gender, diagnosis, operative side, bilateral operations, and previous surgeries. Patients were evaluated for clinical recovery and perioperative complications at 9 and 24 weeks. The study group recovered faster at both followup examinations. The study group had fewer perioperative and postoperative complications compared with the control group. Accuracy of component positioning was not compromised compared to the control group. Less invasive surgery with the philosophy of maximally preserving the abductors, posterior capsule, and short rotators may result in a safer operation with faster recovery than traditional techniques.

Prospective and comparative study of the anterolateral mini-invasive approach versus minimally invasive posterior approach for primary total hip replacement. Early results

The interest in minimally invasive approaches for total hip replacement (THR) has not waned in any way. We carried out a prospective and comparative study in order to analyse the interest of the anterolateral minimal invasive (ALMI) approach in comparison with a minimally invasive posterior (MIP) approach. A group of 35 primary THRs with a large head using the ALMI approach was compared with a group of 43 THR performed through a MIP approach. The groups were not significantly different with respect to age, sex, bony mass index, ASA score, Charnley class, diagnoses and preoperative Womac index and PMA score. The preoperative Harris Hip Score was significantly lower in the ALMI group. The duration of surgical procedure was longer and the calculated blood loss more substantial in the ALMI group. The perioperative complications were significantly more frequent in this group, with four greater trochanter fractures, three false routes, one calcar fracture, and two metal back bascules versus one femoral fracture in MIP group. Other postoperative data (implant positioning, morphine consumption, length of hospital stay, type of discharge) are comparable, such as the early functional results. No other complication has been noted during the first 6 months. The ALMI approach uses the intermuscular interval between the tensor fascia lata and the gluteus medius. It leaves intact the abductor muscles, the posterior capsule and the short external rotators. The early clinical results are excellent, despite the initial complications related to the initial learning curve for this approach and the use of a large head. The stability and the absence of muscular damage should permit acceleration of the postoperative rehabilitation in parallel with less perioperative complications after the initial learning curve.