Migration characteristics and early clinical results of the NANOS® short-stem hip arthroplasty

Purpose: The aim of the study was to systematically evaluate clinical outcomes of tapered fluted stems, either monoblock or modular, in revision total hip arthroplasty. Methods: PubMed, EMBASE and Web of Science and Cochrane databases were systematically searched by 2 researchers. Clinical studies reporting primarily on survival and re-revision rates, and secondarily on subsidence, dislocation, intraoperative fractures, periprosthetic fractures and infection were included. 2 investigators assessed the quality of the studies. Results: 46 studies were included in this review, reporting on 4601 stem revisions. The pooled re-revision rate was 5.1% and long-term survival ranged from 75% to 98.5%. No differences were observed between monoblock and modular stems regarding re-revision rate, dislocation rate, periprosthetic fracture rate or infection rates. Monoblock stems exhibited more subsidence and modular stems displayed more intraoperative fractures. Conclusions: Satisfactory results can be obtained with the use of tapered fluted end-bearing stems. Monoblock stems offer the same clinical results as modular stems.

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Abductor Muscle Force after Straight-Stem Compared to Short-Stem Total Hip Arthroplasty through a Modified Direct Lateral Approach: Functional Assessment of 70 Consecutive Patients of a Randomized Controlled Clinical Trial

Journal of Clinical Medicine ◽

10.3390/jcm10061235 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1235

Author(s):

Michael Fuchs ◽

Marie-Anne Hein ◽

Martin Faschingbauer ◽

Mirco Sgroi ◽

Ralf Bieger ◽

...

Keyword(s):

Clinical Trial ◽

Muscle Strength ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Lateral Approach ◽

Short Stem ◽

Abductor Muscle ◽

Total Hip ◽

Straight Stem ◽

Direct Lateral Approach

Because of preservation of proximal femoral bone stock and minimized soft tissue trauma, short-stem implants are becoming increasingly important in total hip arthroplasty (THA). The postulated advantage regarding the functional outcome has not been verified. We hypothesized an increased abductor muscle strength by the use of a short-stem design. Seventy consecutive patients of a randomized clinical trial were included. Of these, 67 patients met the inclusion criteria after 12 months. Thirty-five patients received a standard straight stem and 32 patients a short-stem femoral component. All surgeries were performed by a modified direct lateral approach. Isometric muscle strength of the hip abductors was evaluated preoperatively 3 and 12 months after surgery. Harris hip score (HHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were evaluated. After three months, there were no differences between the two groups; the abductor force was comparable to the preoperative initial values. After 12 months, a significant increase in muscle strength for the short stem patient group compared to preoperative baseline values was measured (straight-stem THA, 0.09 Nm/kg ± 0.4, p = 0.32; short-stem THA, 0.2 Nm/kg ± 0.3, p = 0.004). Comparison of the 12-month postoperative total HHS and WOMAC revealed no significant differences between both groups. A significant increase in hip abductor muscle strength 12 months after short-stem THA compared to conventional-stem THA was observed.

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Short-stem total hip arthroplasty is not associated with an earlier return to work compared to a straight-stem design

Scientific Reports ◽

10.1038/s41598-021-82805-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Georg Hauer ◽

Maria Smolle ◽

Sabrina Zaussinger ◽

Joerg Friesenbichler ◽

Andreas Leithner ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Sick Leave ◽

Return To Work ◽

Hip Arthroplasty ◽

Short Stem ◽

Multivariate Linear Regression Analysis ◽

Stem Design ◽

Total Hip ◽

Straight Stem ◽

Significant Difference

AbstractReturn to work (RTW) has been specifically identified as a high priority in patients undergoing total hip arthroplasty (THA). This investigation sought to assess the effect of the stem design on patients’ RTW. Secondly, the study aimed to identify risk factors that lead to a delayed RTW. Questionnaires inquiring about RTW, employment history, educational level, type of work, physical demands and joint awareness were administered by post. Further data were collected from patients’ hospital records. 176 patients who underwent THA using a short-stem and 97 patients using a straight-stem design were compared. The median return to work time was 10 weeks [IQR 7–14 weeks], with no significant difference between the two groups (short stems vs. straight stems; 10 [IQR 7–14] vs. 11 [7.5–13.5] weeks; p = 0.693). In the multivariate linear regression analysis, self-employment vs. employee (p = 0.001), dimension of preoperative workload (p = 0.001), preoperative sick leave (p < 0.001), and hospital length of stay (LOS) (p < 0.001) independently affected the period until work was resumed. The Forgotten-Joint-Score-12 showed no significant difference between the two groups. The data show that the majority of THA patients can expect to resume work and stem design has no impact on RTW. Employees with preoperative sick leave, prolonged hospital LOS and low workload are at higher risk for a delayed RTW.

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The impact of reducing the femoral stem length in total hip arthroplasty during gait

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-021-03852-w ◽

2021 ◽

Author(s):

Anatole Vilhelm Wiik ◽

Adeel Aqil ◽

Bilal Al-Obaidi ◽

Mads Brevadt ◽

Justin Peter Cobb

Keyword(s):

Total Hip Arthroplasty ◽

Gait Analysis ◽

Hip Arthroplasty ◽

Femoral Stem ◽

Short Stem ◽

Stem Length ◽

Practical Consideration ◽

Total Hip ◽

Long Stem ◽

The Impact

Abstract Aim The length of the femoral stem in total hip arthroplasty (THA) is a practical consideration to prevent gait impairment. The aim of this study was to determine if reducing the femoral stem length in THA would lead to impaired gait biomechanics. Methods Patients uniformly with the same brand implant of differing lengths (100 mm vs 140–166 mm) were taken retrospectively from a prospective trial introducing a new short stem. Twelve patients without any other disorder to alter gait besides contralateral differing length stem THA were tested at differing gradients and speed on a validated instrumented treadmill measuring ground reaction forces. An anthropometrically similar group of healthy controls were analysed to compare. Results With the same posterior surgical approach, the offset and length of both hips were reconstructed within 5 mm of each other with an identical mean head size of 36 mm. The short stem was the last procedure for all the hips with gait analysis occurring at a mean of 31 and 79 months postoperatively for the short and long stem THA, respectively. Gait analysis between limbs of both stem lengths demonstrated no statistical difference during any walking condition. In the 90 gait assessments with three loading variables, the short stem was the favoured side 51% of the time compared 49% for the long stem. Conclusion By testing a range of practical walking activities, no lower limb loading differences can be observed by reducing the femoral stem length. A shorter stem demonstrates equivalence in preference during gait when compared to a reputable conventional stem in total hip arthroplasty.

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