Arthroplasty Today最新文献

Background: The study focused on kinematically aligned total knee arthroplasty (KA TKA). It identified which coronal plane alignment of the knee (CPAK) types are associated with a higher proportion of medial deviation of the 6° prosthetic trochlear groove (PTG) relative to the quadriceps' line of pull and whether medial deviation adversely affected the Forgotten Joint Score (FJS). The research calculated the minimum PTG angle required to prevent medial deviation by at least 2° in all patients.

Methods: The study analyzed 296 KA TKAs with a postoperative long-leg scanogram and a 2-year FJS score. Radiographic measurements were used to determine the CPAK type and to identify the deviation of the 6° PTG relative to the quadriceps' line of pull as medial (-) or lateral (+).

Results: Fifty-one percent of KA TKAs had a medial deviation of the PTG, and the proportion was higher in CPAK I, II, III, and VI than in IV and V types (P < .05). The median FJS of CPAK III was significantly lower than I and IV (P < .0262) and comparable to II, V, and VI (P > .085). The minimum PTG angle required to prevent medial deviation by at least 2° in all patients is 17°.

Conclusions: A medial deviation of the 6° PTG occurred in more than half of the KA TKAs and was observed in 4 of 6 CPAK types. Because medial deviation was associated with a lower FJS, it is suggested that the femoral component should have a minimum PTG of 17° to prevent medial deviation by at least 2° in all patients.

Level of evidence: IV.

This report describes a medial calcar episiotomy with partial anterior transfemoral osteotomy of the proximal femur to aid in removal of a femoral component in setting of revision total hip arthroplasty through a direct anterior approach. Revision total hip arthroplasty is challenging, labor-intensive, and carries high complication rates. Previously described techniques such as extended trochanteric osteotomies can be utilized to facilitate removal of fixed femoral stems. The technique herein described was performed in an effort to avoid the morbidity of additional dissection and risk of nonunion associated with complete osteotomy of the trochanteric region. We present a novel technique to aid in the removal of a fixed femoral stem in the setting of revision total hip arthroplasty through an anterior approach. This technique has not previously been described specifically in the literature and was performed safely and effectively for this patient. A complication-free outcome with osteotomy union was achieved on a final follow-up of 13 months.

Iliopsoas tendonitis following total hip arthroplasty (THA) can be challenging to diagnose due to the many causes of postoperative groin pain. This case involves a 66-year-old female with right-sided hip and groin pain and a palpable mass, 3 years post-THA. Initial recovery was unremarkable until the sudden onset of symptoms after exercise. The patient presented with a palpable mass on the groin area and pain and underwent several consults with general surgery and orthopaedics. A series of unremarkable radiogram, biopsies, and negative infectious workup prompted revision surgery, which included acetabular component revision and iliopsoas tenotomy. The patient experienced significant pain relief and improved mobility postrevision. This case highlights a complication of THA and the complexity of diagnosing and treating iliopsoas tendonitis post-THA.

Lower limb amputation has been well characterized in the literature to cause resultant osteoarthritis in the hip of the contralateral limb. This further amplifies the already significant physical disability and morbidity that come with lower limb amputation. The use of total hip arthroplasty (THA) in patients with lower limb amputations is rare, with available literature subsequently also limited. In this case report, we describe a 52-year-old female with a right proximal femur (subtrochanteric) amputation who underwent left THA due to osteoarthritis. To our knowledge, this is the first published report describing THA, via direct anterior approach, in a patient with contralateral proximal femur (subtrochanteric) amputation. We discuss the complex surgical considerations for this patient population, selection of approach, prosthesis, and postoperative outcomes.

Adverse local tissue reaction (ALTR) and osteolysis formation are more frequently described complications after total hip arthroplasty (THA) with metal-on-metal bearings. In this report, we present a unique case of ALTR and osteolysis formation with ceramic-on-ceramic bearing THA, which has been less commonly described in the existing literature. This rare case occurred in a 54-year-old patient who had a primary THA done 17 years prior to representing to our institution. As part of the workup for our patient to find out the underlying cause of his complications, we have carried out extensive investigations that have not been previously reported. We conclude that ceramic bearings in THA may not be entirely inert and may cause complications such as osteolysis and ALTR.

Background: Aseptic loosening is the most common aseptic failure modality following total knee arthroplasty. Recent literature suggests that the implant-cement interface is the "weak-link" in fixation and lipid contamination may drive this debonding pattern. Therefore, the purpose of this study was to determine if the "double-butter" technique would significantly decrease lipid contamination of the tibial tray.

Methods: Transparent acrylic models of 7 different tibial baseplates were created to allow for direct visualization of fluid contamination of the implant-cement interface during experimental cementation. Three cementation techniques were then employed in triplicate for each implant: coating only the tibia ("single butter") and coating of the tibia and baseplate (with and without keel included; "double-butter"). A dye was added centrally to simulate lipid contamination. After each trial, the degree of implant-cement contamination was calculated. Standard statistical analyses were conducted.

Results: With the double-butter technique, there was a significant reduction in contamination for all studied implant designs (range: 0%-7%; P < .05) and contamination was eliminated when the entire implant was coated prior to implantation. The single-butter technique resulted in contamination of 16%-43% of the tibial undersurface. There were significant differences in percent contamination between component designs (P < .05).

Conclusions: Cementation technique and implant design each influenced baseplate lipid contamination. While significant differences were noted between keel geometries, we found that the double-butter technique effectively eliminated baseplate contamination, even in the most susceptible designs in this study. We therefore advocate for the incorporation of the double-butter technique to limit lipid contamination and potentially reduce aseptic tibial loosening.

Background: Unrestricted kinematic alignment (uKA) in total knee arthroplasty (TKA) has the theoretical advantage of reproducing patients' constitutional alignment and restoring the pre-arthritic joint line position and obliquity. However, modifications of the original uKA technique have been proposed due to the potential risk of mechanical failure and instability. Given the significant variability in soft tissue behavior within the same bony morphology group, uKA pure knee resurfacing could be occasionally detrimental. This study aimed to kinematically compare the outcomes of uKA TKA with those of a robotic-assisted KA TKA technique based on specific soft-tissue boundaries.

Methods: In this retrospective gait analysis study, 24 TKA patients and 12 healthy controls were recruited. Inclusion criteria were a 9-month minimum follow-up from successfully, primary medial-pivot or medially-congruent TKA performed for isolated degenerative joint disease. Preoperatively, patients were randomly assigned to two surgical groups: A) uKA (#12) and B) robot-assisted (#12), KA (hybrid-kinematic) with boundaries (±3° from hip-knee-ankle neutral axis) and a slight intercompartmental gap asymmetry (max 2 mm lateral-opening). The gait analysis was performed using instrumented treadmills equipped with 3D cameras.

Results: Sagittal knee kinematic data: during the early-stance phase of gait, the uKA group showed a less consistent weight-acceptance phase and a less efficient transition between the first knee-flexion peak and mid-stance-extension plateau with respect to the hybrid-kinematic alignment group. Spatiotemporal and overall gait quality data: no significant differences were found between the two TKA groups regarding walking speed (P = .51) and step length (P = .8534). Control group patients walked more efficiently compared to TKA groups, showing inferior trunk flexion and inferior variation in step length (P < .0001).

Conclusions: This study showed that restoring the pre-arthritic joint line, as advocated by surgeons following the uKA philosophy, does not guarantee a closer-to-normal knee kinematics.