Radiological Changes in Adjacent and Index Levels after Cervical Disc Arthroplasty

PurposeThe purpose of this retrospective study was to evaluate radiological and clinical outcomes in patients undergoing cervical disc arthroplasty (CDA) for cervical degenerative disc disease. The results may assist in surgical decision-making and enable more effective and safer implementation of cervical arthroplasty.Materials and MethodsA total of 125 patients who were treated with CDA between 2006 and 2019 were assessed. Radiological measurements and clinical outcomes included the visual analogue scale (VAS), the Neck Disability Index (NDI), and the Japanese Orthopaedic Association (JOA) myelopathy score assessment preoperatively and at ≥2 years of follow-up.ResultsThe mean follow-up period was 38 months (range, 25–114 months). Radiographic data demonstrated mobility at both the index and adjacent levels, with no signs of hypermobility at an adjacent level. There was a non-significant loss of cervical global motion and range of motion (ROM) of the functional spinal unit at the operated level, as well as the upper and lower adjacent disc levels, compared to preoperative status. The cervical global and segmental angle significantly increased. Postoperative neck VAS, NDI, and JOA scores showed meaningful improvements after one- and two-level CDA. We experienced a 29.60% incidence of heterotrophic ossification and a 3.20% reoperation rate due to cervical instability, implant subsidence, or osteolysis.ConclusionCDA is an effective surgical technique for optimizing clinical outcomes and radiological results. In particular, the preservation of cervical ROM with an artificial prosthesis at adjacent and index levels and improvement in cervical global alignment could reduce revision rates due to adjacent segment degeneration.     

Artificial disc and vertebra system: a novel motion preservation device for cervical spinal disease after vertebral corpectomy

OBJECTIVE:To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group.METHODS:Biomechanical tests were conducted on 18 human cadaveric cervical specimens. The range of motion and the stability index range of motion were measured to study the function and stability of the artificial disc and vertebra system of the intact group compared with the fusion group.RESULTS:In all cases, the artificial disc and vertebra system maintained intervertebral motion and reestablished vertebral height at the operative level. After its implantation, there was no significant difference in the range of motion (ROM) of C3–7 in all directions in the non-fusion group compared with the intact group (p>0.05), but significant differences were detected in flexion, extension and axial rotation compared with the fusion group (p<0.05). The ROM of adjacent segments (C₃₋₄, C₆₋₇) of the non-fusion group decreased significantly in some directions compared with the fusion group (p<0.05). Significant differences in the C_4-6 ROM in some directions were detected between the non-fusion group and the intact group. In the fusion group, the C₄₋₆ ROM in all directions decreased significantly compared with the intact and non-fusion groups (p<0.01). The stability index ROM (SI-ROM) of some directions was negative in the non-fusion group, and a significant difference in SI-ROM was only found in the C₄₋₆ segment of the non-fusion group compared with the fusion group.CONCLUSION:An artificial disc and vertebra system could restore vertebral height and preserve the dynamic function of the surgical area and could theoretically reduce the risk of adjacent segment degeneration compared with the anterior fusion procedure. However, our results should be considered with caution because of the low power of the study. The use of a larger sample should be considered in future studies.     

The value of postoperative prosthesis alignment and patellar height measurements on standard X-rays after Total Knee Arthroplasty: Does it relate to knee function after 5 years?

Background

The purpose of this retrospective cohort study was to investigate the influence of parameters of malalignment on knee function 5?years post TKA and, additionally, to explore alterations in patellar height after TKA.

Usefulness of gait parameters obtained from inertial sensors attached to the lower trunk and foot for assessment of gait performance in the early postoperative period after total knee arthroplasty

BackgroundThis study was performed to (i) compare gait parameters obtained from inertial sensors attached to the lower trunk and foot between patients in the early postoperative period after total knee arthroplasty (TKA) and healthy age- and sex-matched controls and (ii) elucidate the association between the gait parameters and patient-reported outcome measures (PROMs).MethodThe gait performance of 19 patients who had undergone TKA was assessed using inertial sensors and PROMs obtained from the Knee Injury and Osteoarthritis Outcome Score (KOOS) 1 week before hospital discharge. The patients walked along a 15-m walkway and we calculated the following gait parameters: walking speed, coefficient of variation (CV) of stride time, unbiased autocorrelation coefficient (AC), harmonic ratio (HR), and symmetry index (SI). The same gait parameter data from 19 age- and sex-matched healthy adults (controls) were obtained from our past study.ResultsThe TKA group demonstrated slower walking speed, larger CV of stride time, lower HR in all three directions, lower AC in the vertical direction, and higher SI in the vertical direction than the healthy control group (all p < 0.05). Correlation analysis revealed that the SI in the anteroposterior direction was significantly correlated with the KOOS symptoms subscore and ADL subscore (p < 0.05).ConclusionsPatients in the early postoperative period after TKA exhibited worse gait performance as assessed by inertial sensors compared with healthy controls. Gait symmetry was correlated with PROMs. These results indicate the usefulness of assessing gait parameters after TKA.     

Comparison of the clinical and patient-reported outcomes between medial stabilized and posterior stabilized total knee arthroplasty: A systematic review and meta-analysis

BackgroundTotal knee arthroplasty (TKA) is effective in relieving pain and improving function in patients with end-stage knee osteoarthritis. Both medial stabilized total knee arthroplasty (MS-TKA) and posterior stabilized total knee arthroplasty (PS-TKA) can achieve satisfactory clinical results, but comparisons between MS-TKA and PS-TKA have yielded contradictory conclusions. This systematic review and meta-analysis were performed to investigate the differences in clinical and patient-reported outcomes (PROMs) between MS-TKA and PS-TKA.MethodsIn December 2020, systematic searches of the following databases were undertaken: Pubmed, Embase, Cochrane Library, Clinical Trials.gov. Studies with PROMs comparing MS-TKA to PS-TKA were included. Meta-analysis was conducted for range of motion (ROM), Knee Society Score (KSS), Knee Society Functional Score (KFS), Forgotten Joint Score (FJS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Oxford Knee Score (OKS).ResultsThere were 17 studies included in this review, 13 studies used for quantitative analysis, and 4 studies used for qualitative synthesis. Meta-analysis concluded that the WOMAC mean difference (MD) for MS-TKA was 1.55 higher than for PS-TKA (MD = −1.55; 95 %CI = −2.45 to −0.64, P = 0.0008); however, this difference was less than the minimum clinically important difference (MCID) value of 15. Assessment using the OKS determined that the MD for PS-TKA was 0.58 higher than for MS-TKA (MD = 0.58; 95 %CI = 0.25 to 0.91, P = 0.0006); again, this MD was less than the MCID value of 5. There were no significant differences between MS-TKA and PS-TKA when assessed by ROM (P = 0.23), KSS (P = 0.13), KFS (P = 0.61), or FJS (P = 0.22).ConclusionDerived from numerous sources, utilizing a multitude of validated functional and patient-reported outcome assessment tools, there was no clinically evident advantage of MS-TKA compared to PS-TKA.RegistrationThe registration number on PROSPERO is CRD42021228555.