Blood Loss in the Minimally Invasive Posterior Approach to Total Hip Arthroplasty: A Comparative Study

AIMS: Our primary aimwas to evaluate whether there is really less bleeding in patients for whom the minimally invasive posterior approach is used in comparison with the direct lateral approachfor primary total hip arthroplasty. Our secondary aim was to evaluate the clinical functional results after six months as well as the postoperative radiographic result. METHODS: In a comparative non-random prospective study, 76 adult patients underwent elective total hip arthroplasty using one of two approaches. The minimally invasive posterior approach (34 cases; mini-incision group) was compared with the standard direct lateral approach (42 cases; control group). RESULTS: Lower total estimated bleeding (means of 1083.5 ml versus 1682.3 ml; p < 0.001) and lower intraoperative bleeding (means of 745.6 ml versus 1282.8 ml; p < 0.001) were found in the mini-incision group. There was, however, no difference in the volume of blood drained after the operation (means of 340 ml and 399 ml; p = 0.77). There was also a difference between the two groups regarding the need for allogenic transfusion (8.8% in the mini-incision group versus 28.6%, p = 0.02). We observed a better clinical result in the mini-incision group (p = 0.002) despite the lack of difference between the two groups in relation to the radiographic result. DISCUSSION: Our results draw attention to the possibility that other authors may have underestimated blood losses when using minimally invasive approaches. CONCLUSION: The minimally invasive approach gave rise to a positive final impression with regard to lower blood loss

RESTORATION OF THE ROTATION CENTER IN MINIMALLY-INVASIVE TOTAL HIP REPLACEMENT

Objective: Our aim was to evaluate the challenges in obtaining a successful restoration of the rotation center as well as a good positioning of the acetabular component when using the minimally-invasive posterior approach for uncemented total hip replacement. Methods: In a comparative non-random prospective study, 64 adult patients underwent elective total hip arthroplasty using the minimally-invasive posterior approach performed by one single surgeon, All patients included in this study had a superior and lateral migration of the rotation center of the hip in comparison to the normal contralateral hip. Patients were excluded from the study if they presented the following: diagnosis of femoral neck fracture, displasic hip types 2, 3 and 4 (Crowe`s classification), osteoarthritis of the contralateral hip. Of the 64 patients in the study, 39 had a radiographic pre-op acetabular size planning equal or less than 50 mm and 25 patients had a radiographic pre-op acetabular size planning equal or more than 52 mm. We considered a good result the following goals: acetabular bend between 35 and 50 degrees, acetabular size according to the pre-op estimative with full contact in the three zones of DeLee-Charnley, a lower medial and vertical positioning of the rotation center in comparison with the pre-op values and a final limb discrepancy lower than 10 mm. Results: A better restoration of the rotation center, as well as, excellent acetabular positioning was found in patients with smaller acetabular size (equal or less than 50), p=0, 04. We must draw attention to two risks when using the minimally-invasive posterior approach: a vertical acetabular position and a lateral position of the acetabular component increasing the risk of a poor contact in the zone 1 due to an insufficient reaming of the medial acetabular host bone. Conclusion: We propose standard surgical approaches in patients with larger anatomical measurements (acetabular planning size more than 50)

Use of closed suction drainage after primary total hip arthroplasty: a prospective randomized controlled trial

ABSTRACT Objective: This study aimed to investigate drain use in a controlled population of patients with hip osteoarthritis undergoing primary total hip arthroplasty. Methods: This prospective controlled trial evaluated 93 patients randomized into two groups: a group that received drains and a group that did not. The patients who were randomized to the drain group used a 3.2 mm drain placed under the fascia that was kept in place for 24 h. Postoperative evaluations were performed after 24 h and then three, six, and 12 weeks after total hip arthroplasty. The primary outcome was perioperative blood loss in both groups 24 h after total hip arthroplasty. The other parameters that were evaluated included mid-thigh circumference, the rate of blood transfusion, hematocrit, inflammatory serum levels, and the Harris Hip Score. Results: The clinical and laboratory data revealed no differences between the study groups with respect to blood loss and need for blood transfusion, duration of hospital stay, reoperation rate, complications, inflammatory serum markers, and the Harris Hip Score. Patients without closed suction drainage reported higher pain levels after 24 h (VAS score 1 vs. 2, p < 0.01). Conclusion: Similar clinical and laboratory outcomes were found in both cohorts

Are femoroacetabular impingement tomographic angles associated with the histological assessment of labral tears? A cadaveric study

<div><p>Purpose</p><p>This study sought to investigate the association between tomographic femoroacetabular impingement (FAI) angles and histologically evaluated labral tears. The authors hypothesized that cadavers presenting with cam and pincer morphologies would present a higher prevalence of acetabular labral tears.</p><p>Methods</p><p>Twenty fresh cadavers were submitted to computed tomography. Standard FAI angles were measured, including the alpha angle, femoral version, acetabular version, Tonnis angle and center-edge angle. A cam lesion was defined as an alpha angle greater than 50^o. A pincer lesion was defined as a center-edge angle greater than 40^o, a Tonnis angle less than 0^o or acetabular version less than 0^o. After dissection, three fragments of each acetabulum, corresponding to the antero-superior, superior and postero-superior acetabular rim, were obtained. These fragments were submitted to routine histological preparation. Each slide was evaluated for possible labral tears. Tears were classified according to their Seldes type.</p><p>Results</p><p>The mean age of the cadavers was 50.2 years (SD: 7.4; 13 males). Sixteen (80%) of the cadavers had a cam lesion, and eight cadavers (40%) had a pincer lesion. Histologically, 16 (80%) of the cadavers had a labral tear in at least one region. According to the Seldes classification, 60.7% and 28.6% of these labral tears were type 1 and type 2, respectively. A mixed type of labral tear (10.7%), which represented a new form of Seldes tear, was described. Cadavers with a labral tear had significantly higher alpha angles than other cadavers (53.29^o <i>vs</i> 49.33^o, <i>p</i> = 0.01). Pincer lesions were not associated with labral tears. We found no association between pincer or cam lesions and Seldes classification.</p><p>Conclusion</p><p>Cadavers presenting with higher alpha angles had a higher incidence of labral tears. No association was found between FAI and Seldes classification.</p><p>Clinical relevance</p><p>This study demonstrated a high prevalence of FAI abnormalities associated with histological alterations in a cadaveric sample. Joint damage may be present in the early stages of FAI.</p></div

Illustration of the modified Seldes classification.

<p>Illustration of the modified Seldes classification.</p

Example of a superior fragment.

<p>Black triangle: acetabular labrum; empty triangle: capsule; black star: acetabular cartilage; white star: acetabular bone; black arrow: intact chondrolabral junction.</p

Tomographic angles.

<p>Tomographic angles.</p

Histological slides.

<p>(a) Normal acetabular labrum (Masson’s trichrome stained). (b) Example of a type 1 labral tear associated with cartilage detachment from the acetabular bone (Masson’s trichrome stained). (c) Example of a type 1 labral tear associated with acetabular bone cyst formation (hematoxylin and eosin stained). (d) Example of a type 2 labral tear (hematoxylin and eosin stained). (e) Example of a type 3 labral tear (hematoxylin and eosin stained). Black triangle: acetabular labrum; empty triangle: capsule; black star: acetabular cartilage; white star: acetabular bone; black arrow: chondrolabral junction; striped arrow: acetabular bone cyst; empty arrows: cleavage planes in the labral substance.</p

Macroscopic view of a labral tear associated with full-thickness cartilage loss.

<p>Black triangle: acetabular labrum; empty triangle: capsule; black star: acetabular cartilage; white star: cartilage damage with bone exposure; black arrow: labral tear; white triangle: pulvinar.</p

Demographics.

<p>Demographics.</p