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Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 13 - 13
1 Dec 2022
Reeves J Spangenberg G Elwell J Stewart B Vanasse T Roche C Faber KJ Langohr GD
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Shoulder arthroplasty humeral stem design has evolved to accommodate patient anatomy characteristics. As a result, stems are available in numerous shapes, coatings, lengths, sizes, and vary by fixation method. This abundance of stem options creates a surgical paradox of choice. Metrics describing stem stability, including a stem's resistance to subsidence and micromotion, are important factors that should influence stem selection, but have yet to be assessed in response to the diametral (i.e., thickness) sizing of short stem humeral implants. Eight paired cadaveric humeri (age = 75±15 years) were reconstructed with surgeon selected ‘standard’ sized short-stemmed humeral implants, as well as 2mm ‘oversized’ implants. Stem sizing conditions were randomized to left and right humeral pairs. Following implantation, an anteroposterior radiograph was taken of each stem and the metaphyseal and diaphyseal fill ratios were quantified. Each humerus was then potted in polymethyl methacrylate bone cement and subjected to 2000 cycles of 90º forward flexion loading. At regular intervals during loading, stem subsidence and micromotion were assessed using a validated system of two optical markers attached to the stem and humeral pot (accuracy of <15µm). The metaphyseal fill ratio did not differ significantly between the oversized and standard stems (0.50±0.06 vs 0.50±0.10; P = 0.997, Power = 0.05); however, the diaphyseal fill ratio did (0.52±0.06 vs 0.45±0.07; P < 0.001, Power = 1.0). Neither fill ratio correlated significantly with stem subsidence or micromotion. Stem subsidence and micromotion were found to plateau following 400 cycles of loading. Oversizing stem thickness prevented implant head-back contact in all but one specimen with the least dense metaphyseal bone, while standard sizing only yielded incomplete head-back contact in the two subjects with the densest bone. Oversized stems subsided significantly less than their standard counterparts (standard: 1.4±0.6mm, oversized: 0.5±0.5mm; P = 0.018, Power = 0.748;), and resulted in slightly more micromotion (standard: 169±59µm, oversized: 187±52µm, P = 0.506, Power = 0.094,). Short stem diametral sizing (i.e., thickness) has an impact on stem subsidence and micromotion following humeral arthroplasty. In both cases, the resulting three-dimensional stem micromotion exceeded, the 150µm limit suggested for bone ingrowth, although that limit was derived from a uniaxial assessment. Though not statistically significant, the increased stem micromotion associated with stem oversizing may in-part be attributed to over-compacting the cancellous bed during broaching, which creates a denser, potentially smoother, interface, though this influence requires further assessment. The findings of the present investigation highlight the importance of proper short stem diametral sizing, as even a relatively small, 2mm, increase can negatively impact the subsidence and micromotion of the stem-bone construct. Future work should focus on developing tools and methods to support surgeons in what is currently a subjective process of stem selection


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_22 | Pages 11 - 11
1 Dec 2016
Gustke K
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Use of a short femoral stem for total hip replacement is not a new idea. Morrey first reported on the results of the Mayo Conservative Stem (Zimmer) in 1989. A short femoral stem can also be soft tissue conserving by allowing for a curved insertion track avoiding the abductor attachments. These concepts have made use of a short femoral stem attractive for use in less invasive total hip surgical approaches. The goal of a short femoral stem is to be bone conserving and provide preferential stress transfer to the proximal femur. This may make the short stem desirable for most total hips regardless of surgical approach. The proximal femur has considerable variability in shape, canal size, and offset. This makes a single geometry short stem potentially unstable in some anatomic variants without having a longer stem to resist varus bending moments or obtain diaphyseal stability. The Fitmore Stem (Zimmer) has addressed these anatomic variants by having three different shaped stems with different offsets. The presenter has implanted over 1,000 short stems, using them for both standard and less invasive surgical approaches. There is a learning curve when using these short stems. Initially some stems were undersized and inserted in some varus. Thirty-four percent of the first 100 short stems inserted had measurable subsidence. However, all stabilised with no further subsidence. Rarely, subsidence now occurs with attention to preoperative planning for size and improved surgical technique. The surgical technique for insertion of this short stem is different from a conventional length total hip stem. The canal is broached along a curved track with a posterior and lateral moment applied to the broach. Use of the largest size broach that doesn't sink with moderate impaction forces is necessary to maximally contact the medial and lateral proximal cortices to lessen stem subsidence. Four of over 1,000 stems have been revised for postoperative peri-prosthetic fracture after falls. Two stems were revised for late infection but were not clinically loose. No stems have been revised for aseptic loosening


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_17 | Pages 76 - 76
1 Nov 2016
Gustke K
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Use of a short femoral stem for total hip replacement is not a new idea. Morrey first reported on the results of the Mayo Conservative Stem (Zimmer) in 1989. A short femoral stem can also be soft tissue conserving by allowing for a curved insertion track avoiding the abductor attachments. These concepts have made use of a short femoral stem attractive for use in less invasive total hip surgical approaches. The goal of a short femoral stem is to be bone conserving and provide preferential stress transfer to the proximal femur. This may make the short stem desirable for most total hips regardless of surgical approach. The proximal femur has considerable variability in shape, canal size, and offset. This makes a single geometry short stem potentially unstable in some anatomic variants without having a longer stem to resist varus bending moments or obtain diaphyseal stability. The Fitmore Stem (Zimmer) has addressed these anatomic variants by having three different shaped stems with different offsets. The presenter has implanted over 1,000 short stems, using them for both standard and less invasive surgical approaches, and in all bone types. There is a learning curve when using these short stems. Initially some stems were undersized and inserted in some varus. Thirty-four percent of the first 100 short stems inserted had measurable subsidence. However, all stabilised with no further subsidence. Rarely, subsidence now occurs with attention to pre-operative planning for size and improved surgical technique. The surgical technique for insertion of this short stem is different from a conventional length total hip stem. The canal is broached along a curved track with a posterior and lateral moment applied to the broach. Use of the largest size broach that doesn't sink with moderate impaction forces is necessary to maximally contact the medial and lateral proximal cortices to lessen stem subsidence. Four of over 1,000 stems have been revised for post-operative peri-prosthetic fracture after falls. Two stems were revised for late infection but were not clinically loose. No stems have been revised for aseptic loosening


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 83 - 83
1 May 2016
Trieb K Stadler N
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A large number of short stem prosthesis for hip arthroplasty has been introduced in the last years. The main aim of this device is to preserve the proximal bone stock in order to facilitate revisions in the future. Furthermore there is an increase in young and active patients in total hip arthroplasty that's why it's important to consider minimally invasive, muscle-considering procedures. Short stems allow to make minimal invasive approaches easier and improve the biomechanical reconstruction. However, there is a large increase of publication about short stems there is still little data about survival and revision rates. We report about the outcome of 81 patients, who have recieved NANOS short stem prosthesis between October 2012 and April 2014. The average age of the patient was 61,6. The oldest patient was 78 years old and our youngest patient was 41 years old. The main diagnoses were osteoarthritis in 67 patients, dysplastic osteoarthritis in 8 patients and avascular necrosis of the femoral head in 6 patients. We have included 37 female patients and 44 male patients. 3 patients had the surgery on both sides. The average operating time was 75,2 min ± 20,1 min and the average grading of patients for surgical procedures of the American Society of Anesthesiologists was 1,8±0,7. The patients were hospitalized 9,6 days ± 2,9 days. The average BMI was 28,2±5,2. Along with demographic data and co-morbidities, the Harris Hip Score was recorded pre-operatively and at follow-up. The Harris Hip Score increased from 36,6 ± 14,5 pre-operatively to 94,5 ± 8,8 at the final follow-up. None of the 81 stems were revised this corresponds to a to a survival rate of 100%. Two of the patients suffered from a hip dislocation which was treated in both cases conservative. In further consequence unfortunately one of those patients thrombosed and suffered from a pulmonary embolism. The x-rays haven't shown any radiolucent lines in any patients. All in all our patients reported about an high post-operative satisfaction. The clinical and radiographic results encouraged us to continue to use short stems with metaphyseal anchorage. However, there must be more long-term results to confirm our excellent mid term results


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_22 | Pages 12 - 12
1 May 2013
Stulberg S
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As an increasing number of young, active large patients become candidates for total hip replacements, there is an increasingly urgent need to identify arthroplasties that will be durable, highly functional and amenable to possible future successful revision. In an era when cemented femoral stems were the primary implant option, the concept of a surface replacement was attractive and, perhaps, appropriate. However, cementless femoral stems of many designs now provide dependable long term fixation and excellent, near normal function. However, a number of issues related to cementless stem fixation could be further improved: . –. Optimisation of load transfer to proximal femur to minimize fracture risk and maximize bone preservation. –. Elimination of proximal-distal mismatch concerns, including bowed femurs. –. Facilitation of femoral stem insertion, especially with MIS THA exposures. –. Facilitation of revision with implants capable of providing durable fixation for active patients. The potential benefits of short stem femoral THA implants include: . –. Ease of insertion. –. Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing). –. Facilitation of MIS surgical approaches, especially anterior exposures. –. Optimisation of proximal femoral load transfer with consequent maximisation of proximal bone preservation. However, a number of potential drawbacks may be associated with the use of cementless short stems: . –. Initial and durable fixation may be highly sensitive to implant design and surface treatment. –. The implants may not be suitable for patients with osteopenia. Consistent, reliable identification of patients appropriate for these implants may be difficult. –. There may be a significant learning curve associated with the use of short stem implants. At this time, it is important to realize that not all short stem implants are equal. In view of the reliability of a large number of uncemented femoral stems of conventional length, surgeons should base their use of specific short stems upon clinical evidence of their safety and durability


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 117 - 117
1 Jan 2016
Warita T Kitagawa T Kobayashi H Sato T Takagishi K
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Objective. Recently, the short stem, taken on preservation of the femoral bone, is available on total hip arthroplasty and on femoral head prosthetic replacement. The handling of the short stem is easier than that of standard stem on implantation of femur. However, it would be difficult to make the direction of stem axis straight in femoral marrow cavity. Actually we experienced that the lateral cortical bone of the proximal femur was ground unevenly on rasping for implantation of the short stem. The aim of this study was to identify the efficacy of dulled rasp on implanting the short stem. Subjects and Methods. We examined 42 hips of 39 patients who underwent the primary total hip arthroplasties with short stems in our institution from August 2011 to April 2014. Primary diseases were 28 osteoarthritides, 6 idiopathic osteonecrosises of the femoral heads and 5 others. We categorized N group as using standard rasp with sharpened blades and M group as using modified rasp with dulled blades named ‘Mild Rasp’, and analyzed with the statistical methods. Results. The numbers of N group was 27 hips, consisting of 15 males and 12 females, with a mean age of 60.0 years and a mean body mass index (BMI) of 25.2. The mean time of operation was 149.9 minutes, and the mean amount of bleeding during surgery was 761.0 ml. The median of stem size was 13 (range, 5–17) and the mean declination angle from the femoral axis was 2.9. The numbers of M group was 15 hips, consisting of 4 males and 11 females, with a mean age of 63.1 years and a mean BMI of 27.3. The mean time of operation was 187.1 minutes, and the mean amount of bleeding during surgery was 875.7 ml. The median of stem size was 11 (range, 6–14) and the mean declination angle from the femoral axis was 1.3. The time of operation of the M group was significant longer than that of N group (p = 0.016). The declination angle from the femoral axis of the M group was significant smaller than that of N group (p = 0.005). The other parameters were not significant difference between M group and N group. Discussion. When the short stems were implanted, it was reported to tend to be valgus position in femoral marrow cavity. We considered that it would be easy to grind the cortical bone of the proximal cavity by the rasp with sharpened blades. Therefor we used the rasp with dulled blades, the efficacy was indicated. Conclusions. ‘Mild Rasp’ would be useful for positioning more straight against the femoral axis on total hip arthroplasty


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_10 | Pages 11 - 11
1 Jun 2018
Lombardi A
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The use of short femoral components in primary total hip arthroplasty (THA) represents an attractive option. Advocates tout bone preservation and ease of use in less invasive surgical approaches. In 2006 we adopted the concept and have had experience with over 5,700 short, tapered, titanium, porous plasma-sprayed stems in patients undergoing primary THA. The plasma-sprayed portion of this stem is similar to the longer, standard length TaperLoc stem, with shortening resulting from a 3 cm reduction in length of the distal portion of the implant. However, the proximal aspect maintains the same flat, tapered wedge proximal geometry as the standard stem. During insertion in some femurs it was noted that distal canal fill occurred preferentially to proximal canal fill. This required distal broaching in order to accommodate a larger stem. In an effort to avoid this clinical situation and to improve the gradual off-loading that is the goal of a tapered geometry, the design was modified in 2011 to reduce the profile of the component. Other modifications include a lower caput-collum-diaphyseal (CCD) angle to enhance horizontal offset restoration without increasing leg length, width sizing from 5–18 mm in 1 mm increments, and polished neck flats to increase range of motion. Undoubtedly, porous plasma sprayed tapered titanium stems are successful in primary THA. Short stems can better accommodate proximal-distal femoral mismatch, particularly in hips with a large metaphysis and a narrow diaphysis, hips with an excessively bowed femur, and hips with severe deformity such as that encountered with developmental dysplasia and post-traumatic arthritis. Short stems violate less femoral bone stock, allowing for more favorable conditions should revision surgery become necessary. The concept of a short stem is appealing to patients, who perceive it as less invasive. In addition, short stems facilitate shorter incision surgery and operative approaches such as the muscle-sparing anterior supine intermuscular. Increased canal fill has been associated with distal cortical hypertrophy. Reducing the distal portion of the stem has reduced the incidence of distal canal fill, and allows for placement of a slightly larger implant


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 23 - 23
1 Feb 2017
Iguchi H Mitsui H Kobayashi M Nagaya Y Goto H Nozaki M Murakami S Shibata Y Fukui T Okumura T Otsuka T
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Introduction. Since 1989 we have been using custom lateral-flare stems. Using this stem, its lateral flare can produce high proximal fit and less fit in distal part. Applying this automatic designing software to the average femoral geometries, we can make off the shelf high proximal fit stem (Revelation ®). Putting the off the shelf stem, the original center of the femoral heads were well reproduced. But in DDH cases, severe deformities around hip sometimes make complicated difficulty for better functional reconstruction. They are high hip center such as Crowe II-IV, shortening of the femoral neck, high anteversion etc. DDH cases are well known to have higher anteversion than non DDH cases. There would be no definite explanations for it. The high anteversion would not always be harmful for the preoperative patients. But in some cases, osteophytes are observed at posterior side of the femoral head which make another sphere with different centre. We can guess that the patient's biomechanics had not been matched with the original anteversion. Then posterior osteophytes can correct inappropriate anteversion (self-reduction.) (Fig.1) In those patients, reduction of the anteversion by putting stems twisted into the canal or using modular stems are sometimes done by the surgeons' decision. Younger DDH cases can also be treated with THA, because of the complicated deformities or biomechanical disorders. Short stems are expected to reduce operative invasion and stress shielding then can reserve bone quality and quantity. From these point of view to improve the understanding of the characteristics of the DDH anteversion, and design a DDH oriented short stem could be one of good solution for those cases. Method. For the better understanding of the high anteversion 57 femora (mean anteversion: 34.4 deg.) were analyzed slice by slice. The direction of femoral head centre, lesser trochanter (LTR), linea aspera (aspera) just below LTR, aspera in the middle of the femur and aspera between the last 2 sections. All of the directions were assessed from PC line. To clarify the meaning of the head osteophytes, 35 operated cases were analyzed the extent of the head osteophytes. According to the results, a DDH oriented short stem was designed. Results. Even with the different anteversion, femoral head centres and LTRs were located within limited angle (51.4 +/−7.9 deg.) But aspera just below the LTR had no relation to the LTR direction, but always kept within limited angle (102.0 +/− 4.5) to the PC line. This means that DDH cases have proximal femurs of normal shape. But they are only twisted around the level just below the LTR. From this result, stems for DDH cases can have the same shape with normal stem inside the canal. The posterior osteophytes had reduced 4.6+/− 3.0 degree in average independently to the extent of anteversion. There was no tendency that higher anteversion cases have higher self-reduction angle. the stems were give the same shape inside the canal with stems for non DDH cases but its femoral head center was located with 5 degrees less anteversion


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 35 - 35
1 May 2016
McTighe T Brazil D Keggi J Keppler L McPherson E
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Over the past 10 years, the orthopedic community has witnessed an increased interest in more conservative surgical techniques for hip arthroplasty. During this time, second-generation hip resurfacing and minimally invasive surgery enjoyed extensive marketing attention. After a decade of this renewed interest, both of these methods have met with serious concerns. As hip resurfacing numbers decline, both patients and surgeons are looking for other potentially successful conservative treatments to THA. This search has focused surgeon interest toward short-stem designs. Today, a variety of short-stem implants are available with very little clarification of design rationale, fixation features, surgical technique, and clinical outcomes. Virtually every major implant company now offers a “short stem,” and now there are a plethora of different designs. It is important to note, however, that not all short stems achieve initial fixation at the same bone interface region. Furthermore, surgical techniques vary greatly, and postoperative radiographic interpretation of short-stem position and fixation need to be carefully scrutinized. The purpose of this paper is to review past, present, and potential future developments of short femoral stems and to present a classification system that can offer guidance when reporting on the many different stem variations. Short Curved neck-sparing stem (JISRF classification 2a). Recently, new designs are following Pipino's Biodynamic stem style of saving the femoral neck. These designs feature a short curved stem that finds its stabilization contact region in the femoral neck and saves considerable bone in the medial calcar region. In addition, the curvature of the stem prevents violation of the lateral trochanteric region. The shorter stem also reduces blood loss by not reaming the femoral canal distally. These style stems generally have a variable stem length between 90 and 135 mm. This might not appear much shorter than conventional cementless stems (110 to 150 mm). However, the shorter curved neck sparing stems penetrate on average 1 to 2 cm less distally in the femoral canal. Short stems have a definite role in modern THA, as greater emphasis is being placed on soft tissue and bone sparing techniques and as refinements continue in the understanding of proximal femoral fixation. Metaphyseal short stems have significantly less surface contact area compared with conventional length stems and as a result, they might have less torsional and axial resistance. Neck-retaining short stems provide additional axial and torsional stability and reduced stress at the implant– bone interface and may be a consideration in the more active patient profile. Bone quality and the patient's physical activity should be considered prior to the selection of short-stem devices. Many short-stem designs have considerably different style features that may alter bone remodeling. Knowing the design and the required technique is vital to fit the device properly to the patient. The variations of short stems available call for caution in their overall use until there is better understanding of how dependent these stems are on individual stem features, bone quality, and surgical techniques. Overall, the authors are cautiously optimistic and continue advocating their selective use


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 58 - 58
1 May 2016
Suksathien Y Suksathien R
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Background. The short stem prosthesis showed good results in patients with primary osteoarthritis. However, there were a few studies about the short stem THA in patients with osteonecrosis of the femoral head (ONFH). Objective. To evaluate the clinical and radiographic results of the short stem THA in patients with ONFH. The authors hypothesized that the short stem THA would be a promising procedure for patients with ONFH. Material and Method. The authors reviewed 120 osteonecrotic hips in 93 patients who underwent THA with Metha® short stem from November 2010 to February 2013. The appearance of bone trabeculae development and radiolucent line was reviewed using Gruen's classification. The Harris hip score (HHS) was recorded at 6, 12, 24 and 36 months postoperative for evaluating the clinical results. Results. The mean age of patients was 44.4 years (18–68) with the mean BMI of 22.7 (15.1–32.5, SD 3.5). The average follow-up period was 29.2 months (20–47). The mean HHS was significantly improved from 43.9 (22.7–74, SD 7.7) preoperatively to 97.7 (85.9–100, SD 2.7) at 6 months postoperatively (p<0.01). The radiographic change around the stems showed bone trabeculae development at zone 1 (77 cases)(64.2%), 2 (27 cases)(22.5%), 3 (106 cases)(88.3%), 6 (120 cases)(100%) and 7 (115 cases)(95.8%). There was 1 case (0.8%) of 5 mm subsidence and the radiolucent line was observed in zone 1. There were 6 cases (5%) of intraoperative femoral fractures and were treated with cerclage wires, no further subsidence was observed. There was 1 case (0.8%) of distal stem perforation which had stable bone ingrowth. No revision was required. Conclusion. The clinical and radiographic results of the short stem THA in patients with ONFH are generally satisfactory. Its design enables preservation of the bone stock and the bone trabeculae appear to confirm the assumption of proximal force transmission. The authors believe that the short stem THA is a promising procedure for patients with ONFH


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 147 - 147
1 Feb 2020
Yang D Huang Y Zhou Y Zhang J Shao H Tang H
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Aims. The incidence of thigh pain with the short stem varies widely across different studies. We aimed to evaluate the incidence and characteristics of post-operative thigh pain after using a particular bladed short stem and its potential risk factors. Patients and Methods. We respectively reviewed 199 consecutive patients who underwent unilateral total hip replacement using the Tri-lock stem from 2013–2016, of which 168 patients were successfully followed up with minimum two year clinical follow-up. All information about thigh pain and pre- and postoperative HHS score were gathered and all preoperative and immediate postoperative radiographs were available for review. Any complications were recorded. Results. Of the 168 patients, 34 (20.2%) patients reported thigh pain at a mean 3.1 years after surgery. Of these, 2 (5.9%) reported severe pain (NRS 5 or more). The pain was persistent (from surgery to final follow-up) in 13 patients (38.2%) and subsided within 2 years in 10 cases (29.4%). The most common site of pain was the lateral thigh (70.6%). The HHS improved from a mean 54.2 points preoperatively to 79.8 postoperatively. In 123 cases with radiographs at more than 2 years follow-up, all femoral stems were well-fixed and no revision surgery was needed at the latest. BMI and CFI were found to be independent risk factors for thigh pain after using this particular stem component. Conclusions. The incidence of thigh pain in Chinese THA patients with a bladed short stem component design is as high as 20%. Among them, nearly 40% will have some disruption in sleep or daily life. More than one-third of the cases of thigh pain were persistent. A larger BMI and patients with a funnel-type morphology of the femoral canal are independent risk factors for thigh pain in the setting of this particular stem component


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 227 - 227
1 Mar 2013
Kirwan D
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An increasing use of short stem femoral components (SSA), in favour of conventional or “shaft” stems in THA has been reported. SSA components have been reported as bone conserving. Shaft stems are a proven and accepted form of treatment. FEA studies predict more physiological loading of bone with SSA. Cadaver femur studies demonstrate adequate stability for bone ingrowth, more physiological loading of the femur and reduced stress shielding with SSA. Clinical studies report improved outcomes with SSA compared to shaft stems (reduced bone loss, reduced pain, reduced intra-operative complication rate, improved early rehabilitation times and reduced overall cost). A mechanical analysis, to examine the reported improved outcomes with short stems and a rationale for the use of short stems rather than shaft stems is considered


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_7 | Pages 24 - 24
1 Apr 2017
Dorr L
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Short stems are an option for primary THR, but these are the technical challenges. Stem anteversion is increased with short stems usually above 20 degrees so cup anteversion must be adjusted lower. Offset is better if increased up to 5 mm more because more bony neck is retained and with increased stem anteversion the greater trochanter is more posterior, and both of these increase the risk of bony impingement. Short stems are best in A bone, okay in B bone, not recommended yet in C bone. With standard stems performing so well use caution for conversion to short stems


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 96 - 96
1 May 2016
Oh K Ko Y
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Purpose. The positon of short stem is affected by the native anatomy of femoral neck and also by fixation mechanism dependent on design. As a consequence, it has been speculated that restoration of hip geometry might be limited in total hip arthroplasty (THA) using short stem. Therefore, the present study assessed the predictability of restoration of hip geometry using two different CCD-angled short stem engaging the lateral cortex. Materials and Methods. The 60 patients included 15 females and 45 males. The average age was 48.0 years with average BMI 24.2. Biomechanical parameters of hip geometry were analysed on postoperative calibrated radiographs in 30 consecutive primary unilateral THAs using short stem (Metha®, B. Braun Aesculap, Tuttlingen, Germany) with 120° CCD angle (group I) and 30 match controlled cases with 135° CCD angle (group II) and compared to those of the contralateral hip without deformity. The matching process was done before collecting the radiographic measurements by two blinded observer and was for sex, age ± 5 years, and BMI ± 7 units in that order. Results. Head length was short in 40%, 67%, medium in 37%, 23% and large in 23%, 10% of the patients in each group respectively with no significant difference in between group (p=0.11). The discrepancies of horizontal hip center of rotation (△HHCR) and the vertical hip center of rotation (△VHCR) compared to the contralateral side was similar in both groups (p=0.95, p= 0.11, respectively), which enabled to make a direct comparison of the femoral reconstruction. Compared to the contralateral side, discrepancies of limb length (△LLD) showed a borderline significant difference between two groups (avr.+0.7mm, +2.5mm respectively, p=0.04) with higher values for group of 135° CCD angle (more than 5mm of LLD in 27%). However, in group of 120° CCD angle, the discrepancies of horizontal femoral offset (△HFO) and abductor lever arm (△AbLA) (avr. +5.9 mm, +4.9mm respectively) revealed significantly increased compared with balanced value of group 135° CCD angle (+0.9mm, p <0.0001, +1.3mm, p=0.02, respectively) and about half of patients in group of 120° CCD angle revealed outside the 5mm difference target in either horizontal femoral offset (53% of patient) and abductor lever arm (50% of patient). Conclusion. With decreasing CCD-angle of short stem, restoration of limb length appears more predictable but, horizontal femoral offset and abductor lever arm increased with outside of a beneficial range. This tendency should be taken into consideration when choice the design of this kind of neck-preserving short stem as well as exact implantation technique


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 260 - 260
1 Mar 2013
McTighe T Stulberg SD Keppler L Keggi J Kennon R Aram T McPherson E
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Introduction. The use of short stems has been growing in THA for the past five years. As a result, a large number of short stem designs are available in the market place. However, fixation points differ for many of the designs resulting in different radiographic modeling creating confusion when trying to collate to clinical findings. We have created a classification system in an attempted to provide clarity in analyzing radiographic and clinical findings. Method. Femoral implants described as “short stems” were evaluated. The range of lengths for stem type and the method of achieving initial implant stability was determined. The optimal radiographic position of each of these implants and type of bone remodeling associated with this placement was evaluated. Stems were defined as “short” if the tip reached or was proximal to the metaphyseal-diaphyseal junction. This location on the proximal femur was defined as the place at which the medial-lateral metaphyseal flare became parallel. Stems were then classified as: 1.) Metaphyseal Stabilized; 2.) Neck Stabilized; 3.) Head Stabilized. An analysis of radiographic with a minimum of one year follow up were reviewed and posted as to the classification system. Results. The range of stem lengths for stem type and the method of achieving initial implant stability was determined. A classification of short-stemmed components has been defined, making it possible to evaluate and differentiate both radiographic and clinical findings. Not all so-called short stems exhibit the same radiographic and clinical findings. It also became apparent that the different stabilization points require specific surgical techniques to ensure reproducible good results. Findings for neck stabilized present with different findings as compared to metaphyseal stabilized and head stabilized. We are optimistic that this classification system will help to compare short-stemmed implants and how they performed to the more traditional convention cementless stems


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_1 | Pages 11 - 11
1 Feb 2015
Lombardi A
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As an increasing number of young, active, large patients are becoming candidates for total hip replacements, there is an increasingly urgent need to identify arthroplasties that will be durable, highly functional and amenable to possible future successful revision. In an era when cemented femoral stems were the primary implant option, the concept of a surface replacement was attractive and, perhaps, appropriate. However, cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sex and level of activity. However, a number of issues related to cementless stem fixation could be further improved: Optimization of load transfer to proximal femur to minimise fracture risk and maximise bone preservation; Elimination of proximal-distal mismatch concerns, including bowed femurs; Facilitation of femoral stem insertion, especially with MIS THA exposures; Facilitation of revision with implants capable of providing durable fixation for active patients. The potential benefits of short stem femoral THA implants include: Ease of insertion; Reproducibility of insertion; Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing); Facilitation of MIS surgical approaches, especially anterior exposures; Optimization of proximal femoral load transfer with consequent maximization of proximal bone preservation. The purpose of this presentation is to describe the design rationale and characteristics of short (<115mm) uncemented primary THA femoral stem, to evaluate the clinical and radiographic results of short stems and to discuss the possible drawbacks specific to the use of short stems


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_12 | Pages 74 - 74
1 Jul 2014
Stulberg S
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As an increasing number of young, active, large patients are becoming candidates for total hip replacements, there is an increasingly urgent need to identify arthroplasties that will be durable, highly functional and amenable to possible future successful revision. In an era when cemented femoral stems were the primary implant option, the concept of a surface replacement was attractive and, perhaps, appropriate. However, cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sex and level of activity. However, a number of issues related to cementless stem fixation could be further improved: Optimisation of load transfer to proximal femur to minimise fracture risk and maximise bone preservation; Elimination of proximal-distal mismatch concerns, including bowed femurs; Facilitation of femoral stem insertion, especially with MIS THA exposures; Facilitation of revision with implants capable of providing durable fixation for active patients. The potential benefits of short stem femoral THA implants include: Ease of insertion; Reproducibility of insertion; Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing); Facilitation of MIS surgical approaches, especially anterior exposures; Optimisation of proximal femoral load transfer with consequent maximisation of proximal bone preservation. The purpose of this presentation is to describe the design rationale and characteristics of short (< 115mm) uncemented primary THA femoral stem, to evaluate the clinical and radiographic results of short stems and to discuss the possible drawbacks specific to the use of short stems


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_7 | Pages 23 - 23
1 Apr 2017
Stulberg S
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Cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sexes and level of activity. However, a number of issues related to cementless stem fixation could be further improved: Optimization of load transfer to proximal femur to minimise fracture risk and maximise bone preservation; Elimination of proximal-distal mismatch concerns, including bowed femurs; Facilitation of femoral stem insertion, especially for Anterior and MIS exposures; Facilitation of revision with implants capable of providing durable fixation for active patients. The potential benefits of short stem femoral THA implants include: Ease of insertion; Reproducibility of insertion; Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing); Facilitation of MIS surgical approaches, especially anterior exposures; Optimization of proximal femoral load transfer with consequent maximization of proximal bone preservation. The purpose of this presentation is to describe the design rationale and characteristics of short (< 120 mm) uncemented primary THA femoral stems and to evaluate the clinical and radiographic results of short stems. Outcome results extending beyond 10 years support the proposition that short stems of appropriate design provide dependable long-term fixation and equivalent clinical results to those currently achievable with cementless stems of conventional length in patients of all ages, sexes and level of activity


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 125 - 125
1 Jan 2016
Pourmoghaddam A Kreuzer S Freedhand A
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Introduction. The concept of neck preserving stems, known as short femoral stems or metaphyseal stems has been utilized to improve the outcomes of standard cementless stems. The preservation of the proximal femoral bone stock results in decreasing the potential stress shielding and thigh pain. Additionally, these stems may be used in less invasive procedures and provide the option for easier revision procedures if implant failure occurs. In this study we aim to demonstrate the clinical outcome of direct anterior approach of total hip arthroplasty (THA) with short stem prosthesis. Methods. In this study, 390 total cases of THA in 345 patients who underwent an anterior approach of THA by using a new type of short-stem prosthesis (Minihip, Corin) between 2009 and 2013 were reviewed. There were 282 male and 62 female patients and Table 1 summarizes the demographics. In 48 cases avascular necrosis (AVN) was the diagnosis and 339 cases were reported to be due to osteoarthritis. Twenty eight patients were assessed to have American Society of Anesthesiologist (ASA) physical functional score of class I, 258 patients had class II, 103 had class III, and 1 had class IV. Table 2 shows the Charnley classification of the patients. In the current study we evaluated the outcomes of the surgery by utilizing Hip Disability and Osteoarthritis Outcome Score (HOOS) subscales (Pain, Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport) and hip related Quality of life (QOL)). Results. All HOOS subscores were significantly increased from preoperative assessments (F (5,97) = 1679, p < 0.001). The outcome are summarized in Table 4 and Figure 1. No failure of the implant has yet been reported however in 9 cases (2%) calcar fracture occurred during the surgery that were successfully treated with cerclage wires. While no implant loosening was observed, there were four cases (1%) with asymptomatic subsidence (≥ 2mm). Conclusion and Discussion. This study continues to support the excellent clinical outcomes of this short-stem prosthesis when is used for primary total hip arthroplasty. Based on the current findings, we expect that this short stem implant is an excellent choice particularly for younger individuals


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 95 - 95
1 May 2016
Cucciniello C
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The charateristic of Brexis short stem are:. -Minimal bone loss. -Physiologic load transmission. -Solid anchorage. -Biocompatibility and osteointegration. -Polished brilliant in use