Native hip geometry restoration in total hip arthroplasty: a retrospective analysis of eight different short stems.

PURPOSE: To compare different types of short stems (SS) in terms of native hip geometry reproducibility, analyzing centrum-collum-diaphyseal angle (CCD) and femoral offset (FO). These parameters allow the SS to be adapted to patient's anatomy in order to ensure better functional outcomes in total hip arthroplasty (THA). METHODS: A total of 387 cases of SS met the inclusion criteria. CCD and FO were measured using MediCAD® software Version 6 in preoperative (preop-) and postoperative (postop-) X-rays at 6-12 months after surgery. Considering preop-CCD, the sample was divided into three groups: ≤ 124.9° (A); 125°-129.9° (B); and ≥ 130°(C). Preop- and postop-CCD and FO and the respective average difference (Δ) were examined considering the SS individually and within groups, to verify reproducibility of these parameters. RESULTS: The SS considered were eight: Fitmore Zimmer, Pulchra Adler, TRIS Adler, Trifit Corin, Trilock Depuy, Actis Depuy, Profemur Microport, and SMF Smith&Nephew. Groups A, B, and C consisted, respectively, of 113, 124, and 150 cases. Considering all cases, there was a statistically significant (p < 0.05) increase in CCD and FO with surgery. Overall, Trifit and Trilock stems were the best in reproducing preop-CCD, Trifit itself followed by Pulchra and Profemur for preop-FO. In groups A and C, the reproduction of preop-CCD was better than preop-FO, in contrast in group B. With regard to preop-CCD reproduction, in group A Trifit and Pulchra, in group B Fitmore and Trifit, and in group C Fitmore and Pulchra were the best. Fitmore in group A, SMF in group B, Pulchra and Trilock in group C were the worst in reproducing preop-FO. CONCLUSION: Each hip anatomy is unique, and reproduction of preop-CCD and preop-FO can be achieved with different SS characteristics. Accurate knowledge of the stems and performing correct preop- planning are crucial to allow the best restoration of the patient's native hip geometry in THA.

Treatment of Scaphoid Non-Unions with Custom-Made 3D-Printed Titanium Partial and Total Scaphoid Prostheses and Scaphoid Interosseous Ligament Reconstruction.

PURPOSE: Treatment of scaphoid fracture sequelae is still an unsolved problem in hand surgery. Custom-made 3D-printed titanium partial and total scaphoid prosthesis and scaphoid interosseous ligament reconstruction (SLIL) are performed in cases of non-union and isolated aseptic necrosis of the proximal scaphoid pole and when it is impossible to save the scaphoid bone, respectively. This study aims to evaluate the clinical, functional and radiographic results after these two prosthesis implantations. METHODS: Between January 2019 and July 2020, nine partial and ten total scaphoid prostheses were implanted using custom-made 3D-printed titanium implants. Evaluation criteria included carpal height ratio (CHR), radioscaphoid angle, wrist extension and flexion, radial deviation and ulnar deviation of the wrist, grip strength and pinch strength, Visual Analogue Scale (VAS), the Disabilities of Arm, Shoulder, and Hand (DASH) score, and the Patient-Rated Wrist Evaluation (PRWE). RESULTS: Clinical, functional, and radiographic improvements were found in all outcomes analyzed for both patient groups. The VAS pain scale obtained the most remarkable improvement at the one-year follow-up. The results of the DASH scores and the PRWE were good, with a great rate of patient satisfaction at the end of the follow-up. SLIL reconstruction also provided excellent stability and prevented a mid-carpal bone collapse in the short- and medium-term follow-up. CONCLUSIONS: A custom-made 3D-printed titanium partial or total scaphoid prosthesis is a viable solution for patients with scaphoid non-union and necrosis or complete scaphoid destruction in whom previous conservative or surgical treatment has failed.

Plain films are not accurate in planning internal fixation in vancouver type B1 periprosthetic femoral fractures and in distinguishing between subtypes B1 And B2.

BACKGROUND: While few studies analysed the diagnostic validity of preoperative radiographs in distinguishing between Vancouver type B1 and B2 periprosthetic femoral fractures (PFFs), no investigation has been conducted to assess the degree of diagnostic validity of preoperative radiographs in identifying the fracture course and planning the most appropriate treatment. We analysed the diagnostic validity of radiographs in detecting the fracture course and stem stability in Vancouver type B PFFs. METHODS: Vancouver type B PFFs with different fracture courses were randomly performed in 36 dried cadaveric femurs in which a femoral broach had previously been implanted. Radiographic images, taken in the coronal and sagittal views, were analysed by 5 orthopaedic surgeons and 2 radiologists who were asked to reproduce the fracture course and to evaluate stem stability. A scoring system was used to determine the injured femoral cortex correctly identified by the examiners. RESULTS: The identification of the fracture course was scored as poor in 52.4% and 56.%, fair in 23% and 23.4% and good in 24.6% and 19.8%, The identification of the fracture course in the coronal and axial vies radiographs was scored in coronal and axial view radiographs respectively. There was no significant difference in the average score obtained by senior and young examiners. In the coronal plane, the fracture course was poorly identified by all examiners in 11 (30.5%) femurs and by 5 or more examiners in 17 (47%). The fracture course was correctly identified by 5 or more examiners in 8 femurs (22%). A vertical fracture involving an emidiaphysis was found in 8 of the 11 femurs in which the PFF was poorly diagnosed by all examiners. Stem instability was correctly diagnosed in 45% of cases. CONCLUSIONS: In type B PFFs preoperative radiographs show a reduced diagnostic validity in identifying the fracture course and, hence, in planning a correct treatment. Potentially unstable vertical fractures involving an emidiaphysis are likely to be poorly diagnosed since most of the fracture course is hidden by the femoral stem. In cementless stems the diagnostic validity of radiographs in diagnosing between Vancouver type B1 and B2 seems to be lower than that reported for cemented stems.

Revisiting the tibial crest as reference for the mechanical alignment of the tibial component in total knee arthroplasty: a cadaveric study on Caucasian tibiae.

PURPOSE: The accuracy of the tibial crest (TC) in guiding the mechanical alignment of the tibial component in total knee arthroplasty (TKA) has been investigated in a few studies on Asian patients. No study analyzed the anatomical variants of the TC. We analyzed the morphological types of the TC in cadaveric tibiae of Caucasian subjects and assessed whether the TC may be considered an accurate guide for the mechanical alignment of the tibial component in TKA. METHODS: The TC and mechanical axis (MA) were identified in 86 dried cadaveric tibiae by placing metal landmarks along the TC course and a guidewire overlapping the MA. Coronal view radiographs were taken in different positions of tibial axial rotation, and the relationships between the TC and MA were analyzed. RESULTS: The TC showed three different patterns, comprising a curved, mixed and straight course in 47 (54.6%), 21 (24.4%) and 18 (20.9%) tibiae, respectively. When a curved course was found, the TC intersected the MA at proximal and distal points located, on average 22.4% and 63.3% along the tibial length, respectively. When a straight course was found, the mean angle between the TC and MA was 2.9°. In 35% of the cases, the two axes differed by more than 3°. CONCLUSION: The TC of Caucasian subjects exhibits a marked variability in its course and relationship with the MA. Unlike the TC in Asian subjects, the TC of Caucasians cannot be considered an accurate anatomical reference to guide the coronal alignment of the tibial component in TKA.

Is postoperative hyponatremia a real threat for total hip and knee arthroplasty surgery?

Postoperative hyponatremia (POH) is thought to be a fearsome complication of orthopedic surgery. Primary aim of this cohort study was to evaluate the incidence of POH and its clinical relevance in elective surgery, outlining differences between total knee arthroplasty (TKA) and total hip arthroplasty, looking for the presence of any risk factor commonly related to POH.Four hundred two patients that underwent total hip arthroplasty and total knee arthroplasty performed between 2016 and 2017 were retrospectively examined. Serum electrolytes, hemoglobin, hematocrit, glucose, and creatinine were evaluated preoperatively and at day 0-I-II from surgery. Age, sex, body mass index, comorbidities, drugs, surgery data, transfusions, postoperative symptoms, and length of stay (LOS) were determined. All surgeries were performed by the same equipe. Patients had the same perioperative management, excluded those that took thiazides, already at risk of POH.Patients were divided in 2 groups: group A, patients with normal postoperative natremia (294 patients) and group B, patients who developed POH (108, 26.9%); 66.7% of these developed POH within 24 hours postoperatively. In group B mean postoperative natremia was 133.38 (127.78-134.85) mmol/L. Two patients (1.8%) developed moderate hyponatremia, no severe hyponatremia was documented. Type of surgery, operation time, LOS, and presence of postoperative symptoms did not show statistically significant differences within groups. At multivariate logistic analysis chronic use of thiazides was the only variable associated to a decreased risk of developing POH (OR = 0.39; P = .03). Hemoglobin postoperative values (OR = 1.22; P = .03), the need of postoperative transfusion (OR = 2.50; P = .02) and diabetes (OR = 2.70; P = .01) were associated to an increased risk of POH.Although 26.9% of our patients exhibited POH, the onset of this disorder had no implication on postoperative symptoms and on LOS. Diabetes and transfusion are factors most often associated to POH.

Exploring the difficulties to improve minimally invasive application with long PHILOS plate in multifocal metadiaphyseal fractures of the proximal humerus: analysis of intraoperative procedure and clinical outcomes.

The MIPO (Minimally Invasive Plate Osteosynthesis) technique for treating metadiaphyseal fractures of the proximal humerus has gained great attention during the past years. The purpose of this retrospective study was to underline all the important difficulties when the MIPO technique is applied, to propose practical solutions and to evaluate the overall clinical outcome of our patients treated with this technique. A total of 14 patients had been operated in two different surgical units, at San Carlo Borromeo Hospital (Milan, Italy - 11 patients) and in Policlinico Umberto I Hospital (Rome, Italy - 3 patients), between June 2013 and November 2016. The humeral fractures were divided according to the Maresca et al. classification system. A lateral deltoid-split or an anterolateral deltopectoral approach was performed in the proximal humerus. In distal approach, an anterior or a lateral window was performed for plate fixation. After a follow-up of 17,4 (range 3-31) months all patients showed fracture healing and there were no non-unions or infected cases. MIPO of the humerus is a tissue sparing technique and in expert hands can improve healing rates and can also reduce complications like nerve damages and infections. In conclusion, we would like to highlight the importance of the MIPO technique as a possible alternative option to the traditional ORIF technique.