The utility of digital templating in Total Hip Arthroplasty with Crowe type II and III dysplastic hips

Purpose Osteochondrodysplasias are characterised by aberrant cartilage and bone development; consequently, patients may be subject to premature hip degeneration. In this population hip arthroplasty outcomes are variable. This series reviews the use of custom femoral implants in total hip replacements for patients with severe skeletal dysplasia. Methods We reviewed 14 hips in nine patients with genetic dwarfism. Computed tomography (CT) scans of the pelvis and femurs were used to create custom titanium stems. Postoperative radiographs were reviewed for migration, osteolysis, fracture and restoration of leg length. Pre-and postoperative Harris hip scores (HHS) were compared, with a mean follow-up of 36.3 months. Mean age was 36.5 years (range 15-50 years) and mean height was 48 inches (range 42-55 inches). Three joints were classified as Crowe type I, two type II, three type III and six type IV. Results Three hips (21%) required revision: two for stem migration and one for acetabular osteolysis. Eleven hips (79%) were stable with signs of osseointegration. No fractures, nerve damage or dislocations occurred. Two stems required cement fixation, and no liners were constrained. Significant osteolysis was seen on three radiographs. All patients walked independently, and mean HHS improved from 45 (24-58) to 71 (47-89). All leg length discrepancies were restored to within 3 mm of equal. Conclusions This study reports good midterm outcomes in a variety of skeletal dysplasias, thus confirming the efficacy of custom femoral implants in the management of this patient group.

Section: Custom Designmentioning

confidence: 99%

Custom total hip arthroplasty in skeletal dysplasia

Osagie

Figgie

Bostrom

2011

“…Precise planning can minimize complications such as femoral shaft fractures, and anatomical variations leading to intra-operative problems can be identified prior to surgery and an optimal or even individualized implant can be selected [6]. Restoration of hip biomechanics can also be simulated and planned digitally.…”

Section: Introductionmentioning

confidence: 99%

Digital templating in total knee and hip replacement: an analysis of planning accuracy

Kniesel

Konstantinidis

Hirschmüller

et al. 2013

Purpose The aim of this study was to determine how well preoperative size selection for total knee and hip arthroplasties based on the digital imaging with and without additional referencing correlated with the size actually implanted. Methods Size selection planning of total knee arthroplasty by digital templating was documented in 46 cases with reference ball (group A) and in 48 cases without ball (group B). In addition, prospective analysis of pre-operative planning was conducted for 52 acetabular components with reference ball (group C) and 69 without ball (group D) as well as stem planning in 38 cases with ball (group E) and 54 cases without ball (group F). The data were analysed and compared with the size of the final component selected during surgery. Results The correlation between planned and implanted size for total knee arthroplasty in group A resulted in femoral anteroposterior (AP) r =0.8622 and lateral r =0.8333 and in group B AP r =0.4552 and lateral r =0.6950. Tibial in group A was AP r =0.9030 and lateral r =0.9074 and in group B AP r = 0.7000 and lateral r =0.6376. For the acetabular components, the results in group C were r =0.5998 and group D r =0.6923. For stems, group E was r =0.5306 and group F r =0.5786. No correlation between BMI and the difference between planned and implanted size was found in any of the groups. Conclusion In the case of total hip arthroplasty there was a relatively low correlation between planned and implanted sizes with or without reference ball. For total knee arthroplasties the already high precision of size planning was further improved by the additional referencing with a reference ball.

“…It also helps to identify the optimal sizes of the components and thereby avoid limb discrepancies, insufficient offset reconstructions, femoral fractures and implant failures due to a lack of stability [2][3][4][5][6]. Templating on radiographs has shown to be a reliable and accurate way to determine the size of the components prior total hip arthroplasty (THA) [5,[7][8][9][10][11][12]. For short-stem total hip arthroplasty (SHA), which was introduced several years ago [13] and recently is increasingly used, only little is known about the accuracy of pre-operative templating [10].…”

Section: Introductionmentioning

confidence: 99%

The accuracy of digital templating: a comparison of short-stem total hip arthroplasty and conventional total hip arthroplasty

Schmidutz

Steinbrück

Wanke-Jellinek

et al. 2012

Purpose Selection of the correct femoral stem size is crucial in total hip arthroplasty for an uncomplicated implantation and good initial stability. Pre-operative templating has been shown to be a valuable tool in predicting the correct implant size. For short-stem total hip arthroplasty (SHA), which recently is increasingly used, it is unknown if templating can be performed as reliable as conventional total hip arthroplasty (THA). Methods A total of 100 hip arthroplasties, 50 with SHA and 50 with THA, were templated by four orthopaedic surgeons each. The surgeons had different levels of professional experience and performed a digital template of the acetabular and femoral component on the pre-operative radiographs. The results were compared with the truly inserted implant size. Results For the femoral stems the average percentage of agreement (±1 size) was 89.0 % in SHA and 88.5 % in THA. There was no significant difference among surgeons in the accuracy of templating the correct stem size and no significant difference between templating SHA and THA. For the acetabular component the average percentage of agreement (±1 size) was 75.8 %. However, the more experienced surgeons showed a significant higher accuracy for templating the correct cup size than the less experienced surgeons. Conclusion Digital templating of SHA can predict the stem sizes as accurately as conventional THA. Therefore digital templating is also recommendable for SHA, as it helps to predict the implant size prior to surgery and thereby might help to avoid complications.