The present study was primarily financially supported by the foundation Vrienden Diergeneeskunde Universiteit Utrecht; MT has received long-term funding from the Dutch Arthritis Society (LLP22); FV and JM are funded by Eurostars Project E115515 - 3DHIP. IK is a holder of a scholarship from the Faculty of Veterinary Medicine, Kasetsart University, Thailand.

Extracapsular 3D-Printed Implant for Restoring Hip Stability in Canines

<ol>
	<li>King, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Etiopathogenesis+of+canine+hip+dysplasia,+prevalence,+and+genetics.">Etiopathogenesis of canine hip dysplasia, prevalence, and genetics.</a> Vet Clin North Am Small Anim Pract. 47 (4), 753-767 (2017).</li><li>Akis, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+association+of+genetic+polymorphisms+of+bone+formation+genes+with+canine+hip+dysplasia.">The association of genetic polymorphisms of bone formation genes with canine hip dysplasia.</a> Iran J Vet Res. 21 (1), 40-45 (2020).</li><li>Loder, R. T., Todhunter, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+demographics+of+canine+hip+dysplasia+in+the+United+States+and+Canada.">The demographics of canine hip dysplasia in the United States and Canada.</a> J Vet Med. 2017, 1-15 (2017).</li><li>Schachner, E. R., Lopez, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosis,+prevention,+and+management+of+canine+hip+dysplasia:+a+review.">Diagnosis, prevention, and management of canine hip dysplasia: a review.</a> Vet Med (Auck)l. 6, 181-192 (2015).</li><li>Vezzoni, A., Boiocchi, S., Vezzoni, L., Vanelli, A. B., Bronzo, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Double+pelvic+osteotomy+for+the+treatment+of+hip+dysplasia+in+young+dogs).">Double pelvic osteotomy for the treatment of hip dysplasia in young dogs).</a> Vet Comp Orthop Traumatol. 23 (6), 444-452 (2010).</li><li>Tavola, F., Drudi, D., Vezzoni, L., Vezzoni, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Postoperative+complications+of+double+pelvic+osteotomy+using+specific+plates+in+305+dogs.">Postoperative complications of double pelvic osteotomy using specific plates in 305 dogs.</a> Vet Comp Orthop Traumatol. 35 (1), 47-56 (2022).</li><li>Koch, D. A., Hazewinkel, H. A. W., Nap, R. C., Meij, B. P., Wolvekamp, W. T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radiographic+evaluation+and+comparison+of+plate+fixation+after+triple+pelvic+osteotomy+in+32+dogs+with+hip+dysplasia.">Radiographic evaluation and comparison of plate fixation after triple pelvic osteotomy in 32 dogs with hip dysplasia.</a> Vet Comp Orthop Traumatol. 06 (01), 09-15 (1993).</li><li>Rose, S. A., Bruecker, K. A., Petersen, S. W., Uddin, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+locking+plate+and+screws+for+triple+pelvic+osteotomy.">Use of locking plate and screws for triple pelvic osteotomy.</a> Vet Surg. 41 (1), 114-120 (2012).</li><li>Remedios, A. M., Fries, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Implant+complications+in+20+triple+pelvic+osteotomies.">Implant complications in 20 triple pelvic osteotomies.</a> Vet Comp Orthop Traumatol. 06 (04), 202-207 (1993).</li><li>Moses, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alternative+surgical+methods+for+treating+juvenile+canine+hip+dysplasia.">Alternative surgical methods for treating juvenile canine hip dysplasia.</a> Aust Vet J. 78 (12), 822-824 (2000).</li><li>Harper, T. A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Femoral+head+and+neck+excision.">Femoral head and neck excision.</a> Vet Clin North Am Small Anim Pract. 47 (4), 885-897 (2017).</li><li>Forster, K. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complications+and+owner+assessment+of+canine+total+hip+replacement:+a+multicenter+internet+based+survey.">Complications and owner assessment of canine total hip replacement: a multicenter internet based survey.</a> Vet Surg. 41 (5), 545-550 (2012).</li><li>Volstad, N. J., Schaefer, S. L., Snyder, L. A., Meinen, J. B., Sample, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metallosis+with+pseudotumour+formation:+Long-term+complication+following+cementless+total+hip+replacement+in+a+dog.">Metallosis with pseudotumour formation: Long-term complication following cementless total hip replacement in a dog.</a> Vet Comp Orthop Traumatol. 29 (4), 283-289 (2016).</li><li>Nesser, V. E., Kowaleski, M. P., Boudrieau, R. 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C. H., Sakkers, R. J. B., Meij, B. P., Evers, L. A. M., Weinans, H. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Method of manufacturing an implant. EP3463198B1. , (2021).</li><li>Brainard, B. M., Hofmeister, E. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anesthesia+principles+and+monitoring.">Anesthesia principles and monitoring.</a> Small Animal Surgery. , (2012).</li><li>Martinez-Taboada, F., Redondo, J. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+hanging-drop+technique+and+running-drip+method+for+identifying+the+epidural+space+in+dogs.">Comparison of the hanging-drop technique and running-drip method for identifying the epidural space in dogs.</a> Vet Anaesth Analg. 44 (2), 329-336 (2017).</li><li>Johnson, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Approach+to+the+craniodorsal+aspect+of+the+hip+joint+through+a+craniolateral+incision+in+the+dog.">Approach to the craniodorsal aspect of the hip joint through a craniolateral incision in the dog.</a> Piermattei's Atlas of Surgical Approaches to the Bones and Joints of the dog and cat. , (2014).</li><li>Whitelock, R. G., Dyce, J., Houlton, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repair+of+femoral+trochanteric+osteotomy+in+the+dog.">Repair of femoral trochanteric osteotomy in the dog.</a> J Small Anim Pract. 38 (5), 195-199 (1997).</li><li>Silveira, C. J., Saunders, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Greater+trochanter+osteotomy+as+a+component+of+cementless+total+hip+replacement:+Five+cases+in+four+dogs.">Greater trochanter osteotomy as a component of cementless total hip replacement: Five cases in four dogs.</a> Vet Surg. 51 (2), 303-310 (2022).</li><li>Archibeck, M. J., Rosenberg, A. G., Berger, R. A., Silverton, C. 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The authors have no conflicts of interest to declare. BM is one of the five inventors of the method of manufacturing an implant to extend the dorsal acetabular rim (2021) of which the patent (EP3463198B1) has been licensed to Rita Leibinger.

Acetabular rim extension using the 3DHIP implant provides advantages over conventional surgical therapies for canine hip dysplasia and has shown promising results to increase coverage of the dysplastic hip joint and reverse hip laxity in short-term follow-up17,18. This publication aimed to showcase the surgical technique with tips and tricks as a surgical manual for implantation of the 3DHIP implant in dogs affected by hip dysplasia.
Selection of candidates for the 3DHIP implant placement-young dogs between 6 and 24 months of age with clinical hip dysplasia marked by hip laxity (FCI grade B-D) with a positive Ortolani subluxation test are adequate candidates. The triradiate acetabular growth plate has to be closed and preferably, no osteoarthritis is present on CT imaging although minor osteophytes up to 2 mm are accepted. Dogs with luxoid hips with near-complete luxation of the femoral head are not accepted for 3DHIP implant placement because of the rapid progression of osteoarthritis, the inability of the femoral head to move into the acetabulum, and expected early conversion to total hip replacement.
There are some critical steps within the surgical technique.
Implant design
Given the individualized design of the 3DHIP implants, a preoperative assessment of the dysplastic hip joint using a CT scan is absolutely mandatory. In addition to the determination of the correct implant size and position of the ventral ilial flange, particularly the amount of acetabular rim extension needed to provide sufficient coverage of the femoral head can be determined.
Surgical approach
A critical step during surgery is sufficient exposure of the dorsal acetabular rim and ventral border of the caudal iliac body for implant placement. The surgical approach to the iliac body and craniodorsal aspects of the hip joint in 3DHIP implantation differs from conventional approaches22. In the presented technique, a trochanteric osteotomy was omitted and a deep gluteal tenotomy was performed while the superficial and middle gluteal muscles were preserved. Hereby, the risk of complications associated with trochanteric osteotomies23,24,25 such as delayed or non-union were avoided and the recovery process was expedited. Additionally, this modified craniodorsal approach can be employed across a variety of ages, breeds, and sizes of dogs without any necessary modifications. Notably, no complications were reported in association with the presented surgical approach.
Correct implant placement
Even though the custom-made 3D-printed hip implant is designed to perfectly fit the unique acetabular anatomy of each dog, imperfect implant placement with 4-5 mm craniocaudal deviation to planning target position was still observed in the first cohort of dogs possibly related to the learning curve with the technique18. The ventral ilial flange of the bone attachment part of the 3DHIP implant allows for more accurate positioning, especially in the dorsoventral direction. However, due to the extracapsular location of the implant, it is still difficult to achieve perfect implant positioning; the inner edge of the acetabulum is obscured by the synovial membrane. Further, osteophyte formation during the lead time of implant production may influence proper implant positioning. To ensure accurate implant positioning according to the preoperative plan, verification using intraoperative fluoroscopy is currently required. It is also expected that with increased experience, the precision of implant positioning will further decrease to below 1-2 mm accurate placement. In the future, guided surgery using 3D-printed surgical drill guides may obviate the need for fluoroscopy.
This technique also has some limitations. Previous short-term results suggest a broad bandwidth of different hip anatomies that can be treated using 3DHIP implants. While the long-term study findings are not yet available, it is advised to consider 3DHIP implantation for dogs that do not exhibit signs of osteoarthritis (OA) or have only a mild degree of OA in their hip joints. The 3DHIP implant placement aims to effectively slow down the progression of hip joint deterioration. Dogs with luxoid hips and moderate to severe hip degeneration as determined in the pre-operative evaluation should be excluded.
Compared to 3DHIP implantation, conventional surgeries to treat canine hip dysplasia such as DPO/TPO present more challenges, especially in a single-stage bilateral procedure and/or in giant dogs due to their invasive nature involving two or three pelvic osteotomies5,6,7,26. Therefore, dogs with bilateral HD can benefit from an acetabular rim extension using a 3DHIP implant; it provides an effective and low invasive single-stage bilateral procedure. In addition, the 3DHIP implantation helps to save valuable time and can prevent the further development of OA that might occur in double-stage bilateral procedures.
To conclude, utilization of the presented 3DHIP implant to extend the dorsal acetabular rim exhibits significant promise as an alternative surgical treatment for hip dysplasia in canines. Especially, the option to offer an effective and low invasive single-stage bilateral procedure for dogs with bilateral hip dysplasia and laxity is an enormous advantage to current alternative treatments. Further monitoring of this new technique in mid- and long-term follow-up is mandatory.

Hip dysplasia (HD) in dogs manifests due to a bad fit between the hip socket (acetabulum) and the femoral head resulting in subluxation of the hip joint. It affects mainly young medium- to large-breed dogs, resulting in joint cartilage deterioration, and ultimately, severe osteoarthritis (OA) leading to chronic pain and low quality of life1,2. The overall prevalence of hip dysplasia in dogs is 15.56%, which varies widely based on breed and classification systems3,4.
Apart from lifestyle changes, hip dysplastic dog patients are treated with antiinflammatory and analgesic drugs to control pain and maintain mobility4. In case of hip laxity in young adult dogs, the only surgical resort is double (DPO) or triple pelvic osteotomy (TPO), a procedure involving two or three full cuts of the pelvic bones to expand the coverage of the femoral head. However, complications after osteotomies are common and the progression of OA is still observed5,6,7,8,9. Once severe OA and chronic pain have developed, only high-impact complex surgery like total hip replacement (THR) or salvage femoral head and neck ostectomy (FHO) remain10. However, FHO presents less favorable outcomes in large breed dogs and necessitates prolonged physical therapy for the restoration of limb function11. Furthermore, THR is technically challenging and inherently associated with severe complications12,13,14. Therefore, effective hip dysplasia therapy necessitating only low-impact surgery and with a lower complication risk is required before this end stage is achieved.
The 3-dimensional (3D)-printed personalized hip implant (3DHIP) is a first-of-a-kind treatment for canine hip dysplasia developed with the intention to offer a minimal traumatic dog-specific implant that restores hip joint stability. The technique involves a titanium implant to treat mainly young adult (6 months to 2 years old) dog patients with a dysfunctional hip joint showing hip laxity grade B (borderline) to D (moderate) according to the F&#233;d&#233;ration Cynologique Internationale (FCI)15. After computed tomography (CT) imaging of the dysplastic joint, an implant is designed following the specific anatomy of the hip joint in a personalized manner to extend the dorsal acetabular rim, thereby preventing hip joint subluxation and restoring hip joint stability.
A previous canine cadaver study revealed that the implant enhanced femoral head coverage and demonstrated failure under an impact force of 1,330 &#177; 320 Newtons16. Subsequently, a pilot study with experimental dogs demonstrated enhanced femoral head coverage, reduced hip laxity, and increased weight bearing by force plate analysis. Furthermore, examination of the intervened hips at 6 months post-implantation revealed normal volume and a smooth surface of both the femoral head and acetabulum cartilage, accompanied by joint capsule hypertrophy based on gross and histological assessments17. Upon confirmation of the efficacy and safety of the implant and treatment concept, a clinical investigation was carried out on client-owned dogs suffering from hip dysplasia. The short-term study revealed that the benefits of the 3D-printed acetabular rim extension implant are a personalized, good fit of the implant to the acetabulum restoring hip joint stability, decreased pain-related activities, and a low-impact surgical procedure18. Application of the implant requires access to the ventrocaudal aspect of the iliac body and the craniodorsal aspect of the hip joint. In this paper, we describe our surgical planning and surgical procedure with a modified craniodorsal approach to the hip joint as a manual for implantation of the 3DHIP in dogs affected by hip dysplasia.

<table><tbody><tr><td>&lt;strong&gt;The laborotory for implant design&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>3D Lab</td><td>University Medical Center Utrecht 3D, Utrecht, Netherlands&amp;nbsp;</td><td></td><td>The laboratory responsible for designing the 3DHIP implant. [https://www.umcutrecht.nl/nl/3d-lab/]</td></tr><tr><td>&lt;strong&gt;Software&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>3-Matic software version 17</td><td>Materialise, Leuven, Belgium</td><td></td><td>CT DICOM data processing</td></tr><tr><td>Materialise Mimics software version 25.1</td><td>Materialise, Leuven, Belgium</td><td></td><td>Software to design the 3DHIP implant on the 3D model of the pelvis</td></tr><tr><td>&lt;strong&gt;Implant manufacturer&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Amnovis</td><td>Amnovis, Aarschot, Belgium</td><td></td><td>Printing and postprocessing of the 3DHIP implant. [https://www.amnovis.com/]</td></tr><tr><td>&lt;strong&gt;Instrument and machine&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>2.4 LeiLOX locking screw titanium</td><td>Rita Leibinger, BW, Germany</td><td>242-224</td><td>Titanium self tapping locking screw 2.4 mm.</td></tr><tr><td>2.7 LeiLOX locking screw titanium</td><td>Rita Leibinger, BW, Germany</td><td>242-227</td><td>Titanium self tapping locking screw 2.7 mm.</td></tr><tr><td>3.5 LeiLOX locking screw titanium</td><td>Rita Leibinger, BW, Germany</td><td>242-235</td><td>Titanium self tapping locking screw 3.5 mm.</td></tr><tr><td>BLUE SEAL 100 x 360 mm</td><td>Interster, Wormerveer, Netherlands</td><td>3FKFB210819</td><td>The transparent sterilization laminate size 100 x 360 mm</td></tr><tr><td>ETHILON 3-0 with FS-1 needle</td><td>Johnson &amp;amp; Johnson Medical GmbH, Norderstedt, Germany</td><td>669H</td><td>Polyamide 6 3-0 (non-absorbable suture material) with 24 mm 3/8c reverse cutting needle using for skin closure</td></tr><tr><td>Fluoroscopy model NZS 229</td><td>Philips, Eindhoven, Netherlands</td><td></td><td>Fluoroscopy</td></tr><tr><td>Foley Catheter 10 fr x 90 cm (36&quot;) with 3 cc Balloon</td><td>MILA international inc., Kentucky, USA</td><td>MLIUC1036</td><td>Foley urine catheter size 10 fr</td></tr><tr><td>Foley Catheter 6 fr x 60 cm (24&quot;) with 3 cc Balloon</td><td>MILA international inc., Kentucky, USA</td><td>MLIUC624</td><td>Foley urine catheter size 6 fr</td></tr><tr><td>Foley Catheter 8 fr x 90 cm (36&quot;) with 3 cc Balloon</td><td>MILA international inc., Kentucky, USA</td><td>MLIUC836</td><td>Foley urine catheter size 8 fr</td></tr><tr><td>Ioban 2</td><td>3M, MN, USA</td><td>6640EU</td><td>Iodine-impregnated surgical drape&amp;nbsp;</td></tr><tr><td>Miele professional G 7826</td><td>Miele Nederland B.V., Vianen, Netherlands</td><td></td><td>The hygienic washing machine&amp;nbsp;</td></tr><tr><td>MMM sterilizer OB10643</td><td>MMM Group, Planegg, Germany</td><td></td><td>Steam autoclave</td></tr><tr><td>MONOCRYL 2-0 with SH Plus needle</td><td>Johnson &amp;amp; Johnson Medical GmbH, Norderstedt, Germany</td><td>MCP3170H</td><td>Poliglecaprone 25&amp;nbsp; plus antibacterial 2-0 (absorbable suture material) with 26 mm 1/2c taperpoint needle using for subcutaneous tissue closure</td></tr><tr><td>MONOCRYL 3-0 with SH Plus needle</td><td>Johnson &amp;amp; Johnson Medical GmbH, Norderstedt, Germany</td><td>MCP3160H</td><td>Poliglecaprone 25&amp;nbsp; plus antibacterial 3-0 (absorbable suture material) with 26 mm 1/2c taperpoint needle using for subcutaneous tissue closure</td></tr><tr><td>PDS 0 with CP needle</td><td>Johnson &amp;amp; Johnson Medical GmbH, Norderstedt, Germany</td><td>PDP485H</td><td>Polydioxanone plus antibacterial 0 (absorbable suture material) with 40 mm 1/2c&amp;nbsp; reverse cutting needle using for muscle fascia and tendon closure</td></tr><tr><td>PDS 2-0 with CP-1 needle</td><td>Johnson &amp;amp; Johnson Medical GmbH, Norderstedt, Germany</td><td>PDP466H</td><td>Polydioxanone plus antibacterial 2-0 (absorbable suture material) with 36 mm 1/2c reverse cutting needle using for muscle fascia and tendon closure</td></tr><tr><td>ProX DMP320&amp;nbsp;</td><td>3D systems, South Carolina, USA</td><td></td><td>Direct metal printing machine using selective laser melting technology&amp;nbsp;</td></tr><tr><td>&lt;strong&gt;Medications&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Betadine oplossing</td><td>Mylan B.V., Amstelveen, Netherlands</td><td>RVG 01331&amp;nbsp;</td><td>Povidone-iodine solution 100 mg/mL (500 mL)</td></tr><tr><td>Betadine shampoo</td><td>Mylan B.V., Amstelveen, Netherlands</td><td>RVG 08943</td><td>Povidone-iodine 75 mg/mL (120 mL)</td></tr><tr><td>Carporal 20 mg</td><td>AST Farma B.V. Oudewater, Netherlands</td><td>REG NL 101766</td><td>Carprofen 20 mg/tablet</td></tr><tr><td>Carporal 40 mg</td><td>AST Farma B.V. Oudewater, Netherlands</td><td>REG NL 115715</td><td>Carprofen 40 mg/tablet</td></tr><tr><td>Carporal 50 mg</td><td>AST Farma B.V. Oudewater, Netherlands</td><td>REG NL 101767</td><td>Carprofen 50 mg/tablet</td></tr><tr><td>Cefazolin Mylan 1 g</td><td>Mylan B.V., Amstelveen, Netherlands</td><td>RVG 16532</td><td>Cefazolin powder 1 g for injection</td></tr><tr><td>Chlorhexidine 0.5% in alcohol 70%&amp;nbsp;spray</td><td>Orphi Farma BV, Lage Zwaluwe, Netherlands</td><td>8711407672906</td><td>Chlorhexidine 0.5% in alcohol 70%&amp;nbsp;spray (250 mL)</td></tr><tr><td>Dexdomitor 0.5 mg/mL</td><td>Orion Corporation, Espoo, Finland</td><td>EU/2/02/033/001-002</td><td>Dexmedetomidine hydrochloride 0.5 mg/mL for injection (20 mL)&amp;nbsp;</td></tr><tr><td>Gabapentin Sandoz 300 mg&amp;nbsp;</td><td>Sandoz B.V., Almere, Netherlands</td><td>RVG 33681</td><td>Gabapentin 300 mg/capsule&amp;nbsp;</td></tr><tr><td>GABAPENTINE TEVA 100 mg</td><td>Teva B.V., Haarlem, Netherlands</td><td>RVG 31980</td><td>Gabapentin 100 mg/capsule&amp;nbsp;</td></tr><tr><td>HiBiScrub</td><td>M&amp;ouml;lnlycke Health Care AB., Utrecht, Netherlands</td><td>RVG 10156</td><td>Chlorhexidine digluconate 40 mg/mL (500 mL)</td></tr><tr><td>Insistor 10 mg/mL</td><td>Richter pharma AG, Oostenrijk, Netherlands</td><td>REG NL 121166</td><td>Methadone hydrochloride 10 mg/mL for injection (10 mL)&amp;nbsp;</td></tr><tr><td>Isoflutek 1000 mg/g</td><td>Laboratorios Karizoo S.A., Barcelona, Spain</td><td>REG NL 118938</td><td>Isoflurane 1000 mg/g (250 mL)&amp;nbsp;</td></tr><tr><td>Levobupivacaine Fresenius Kabi 2.5 mg/mL</td><td>Fresenius Kabi Nederland b.v., Huis ter Heide, Netherlands</td><td>AWA 0611</td><td>Levobupivacaine 2.5 mg/mL solution for injection (10 mL)</td></tr><tr><td>Morfine HCI CF 10 mg/mL</td><td>Centrafarm B.V., Breda, Netherlands</td><td>RVG 50836</td><td>Morphine hydrochloride 10 mg/mL (1 mL)&amp;nbsp;</td></tr><tr><td>Narketan 10</td><td>Vetoquinol B.V., Breda, Netherlands</td><td>vm08007/4090</td><td>Ketamine 10 mg/mL (10 mL)</td></tr><tr><td>Propofol 10 mg/mL</td><td>Fresenius Kabi Nederland b.v., Huis ter Heide, Netherlands</td><td>RVG 110627</td><td>Propofol 10 mg/mL emulsion for injection or infusion (50 mL)&amp;nbsp;</td></tr><tr><td>Rimadyl&amp;nbsp;</td><td>Zoetis B.V., Capelle a/d Ijssel, Netherlands</td><td>REG NL 10101</td><td>Carprofen 50 mL/mL for injection (20 mL)</td></tr><tr><td>Sufentanil-hameln 50 mcg/mL</td><td>Hameln pharma gmbh, Hameln, Germany</td><td>4260016653249</td><td>Sufentanil citrate 50 mcg/mL for injection</td></tr><tr><td>Trazadone EG 100 mg</td><td>EG (Eurogenerics) NV Heizel, Brussel, Belgium</td><td>BE439607</td><td>Trazadone hydrochloride 100 mg/tablet</td></tr></tbody></table>

surgical technique of the 3-dimensional-printed personalized hip implant for the treatment of canine hip dysplasia

Hip dysplasia causes major disability in dogs. Treatment options are limited to palliative treatment (e.g., pain relief, physical exercise, lifestyle changes, and weight control) or invasive surgeries such as pelvic osteotomies and total hip arthroplasty. Hence, a strong unmet need exists for an effective and dog-friendly solution that enhances the quality of life of man&#39;s best friend. We fill this treatment gap by offering a minimally traumatic and extraarticular, dog-specific, 3-dimensional-printed, hip implant (3DHIP) that restores hip joint stability. The surgical treatment using a 3DHIP implant is less invasive than osteotomies and can be performed bilaterally in one surgical session. The 3DHIP implant extends the dorsal acetabular rim of the dysplastic hip joint thereby increasing coverage of the femoral head and inhibiting joint subluxation with fast recovery. Sufficient access to the dorsal acetabular rim and ventral border of the iliac body together with optimal fitting and fixation of the implant are key steps for a successful 3DHIP implantation and imply the need for a specific approach. The present article aims to showcase this innovative surgical technique with tips and tricks as a surgical manual for implantation of the 3DHIP implant in dogs affected by hip dysplasia.

Short-term results of acetabular rim extension have previously been published, arising from an ongoing observational study at the Utrecht University Department of Clinical Sciences18. From December 2019 to March 2022, a total of 61 hips from 34 dogs were included in the study. The cohort consisted of 24 males and 10 females, with a median age of 12 months (ranging from 7 to 38 months) and a median body weight of 27.3 kg (ranging from 12 to 86 kg). Seven dogs underwent surgery on a unilateral hip, while twenty dogs underwent bilateral hip surgery in a single session. Additionally, seven dogs received surgery on both hips, conducted in two separate sessions.
The previous study found a significant increase in the Norberg Angle (NA), linear percentage of femoral head coverage (LFO), and percentage of femoral head coverage (PC) immediately after implantation (Table 1). Moreover, the postoperative Ortolani subluxation sign was negative in 96.7% of operated limbs indicating that the acetabular rim extension implant restored hip congruency and diminished laxity of dysplastic hips18. Particularly, the ability to increase coverage of the femoral head without performing any re-directional osteotomy allowed physiological pelvic geometry retainment. The minimally invasive technique resulted in low incidences of complications (4.9%) in the short-term, encouraged early mobilization, and decreased pain related to activity (Table 1).
Furthermore, this technique allowed single-stage bilateral 3DHIP implant placement. Treated limb(s) were weightbearing without pelvic support within 12 to 24 h after surgery. During the 12-month monitoring period, 3 dogs required revision surgery due to either implant failure (2 dogs) or a significant advancement of osteoarthritis (1 dog). Using the presented surgical approach simultaneously with the suggested hip joint movements (abduction, flexion, and external rotation), better exposure of the ventrocaudal aspect of the iliac shaft and craniodorsal aspect of the hip joint was obtained, facilitating 3DHIP implant positioning. In addition, intra-operative fluoroscopy increased the accuracy of implant positioning.
<img alt="Shoulder joint movement diagram with arrows indicating motion vectors and force directions." class="xfigimg" src="/files/ftp_upload/66005/66005fig1.jpg" data-altupdatedat="1747911167000" data-alt="Figure 1"> 
Figure 1: Schematic illustrations showing a positive Ortolani subluxation sign counteracted by the 3DHIP implant. (A-D) Positive Ortolani subluxation sign. (A) The dog's limb is positioned in neutral flexion and adduction, and a force (red arrows) is exerted towards the dorsum of the dog along the femoral axis that causes (B) dorsal subluxation of the dysplastic hip joint. (C) Gradual limb abduction (blue arrow) is performed while maintaining pressure on the femur. (D) Dependent on the acetabular rim deficiency, the subluxated femoral head falls back into the socket (green arrows). (E) The 3DHIP implant is introduced to enhance the stability of the dysplastic hip joint by reinforcing the hip capsule and labrum, which serve as weight-bearing and stabilizing surfaces (purple arrows). (F) Upon magnification of the rectangular area, the internal 1.5 mm offset of the implant is visible in the red circle, which ensures the capsule attachment remains unaffected. This figure was modified from Willemsen et al.17. Abbreviation: 3DHIP = 3-dimensional-printed, hip implant. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Hip dysplasia evaluation, FCI grading A-E, X-ray comparison chart, veterinary assessment tool." class="xfigimg" src="/files/ftp_upload/66005/66005fig2.jpg" data-altupdatedat="1747911167000" data-alt="Figure 2"> 
Figure 2: Example of the preoperative hip radiographs used for Fédération Cynologique Internationale hip dysplasia classification. Radiographs are taken in the ventro-dorsal hip extended position. From left to right, FCI classifies hip dysplasia into five different categories: A (normal), B (borderline), C (mild hip dysplasia), D (moderate hip dysplasia), and E (severe hip dysplasia). Abbreviation: FCI = Fédération Cynologique Internationale. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="CT scans of hip joints; comparative anatomy; medical imaging analysis; structural differences." class="xfigimg" src="/files/ftp_upload/66005/66005fig3.jpg" data-altupdatedat="1747911167000" data-alt="Figure 3"> 
Figure 3: Images of hip joint CT examinations illustrating osteophytes of varying sizes. The thickness of all featuring osteophytes is measured in both (A,B) coronal planes and (C) transverse planes at the cranial (white arrowhead) and caudal (red arrowhead) acetabular rim and femoral neck (black arrowhead). Dogs that have femoral neck and/or cranial and caudal acetabular rim osteophytes &gt; 2 mm are excluded. CT examination slice thickness is 5 mm. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Pelvic CT scan analysis, 3D bone reconstruction, orthopedic implant fitting, anatomical diagram." class="xfigimg" src="/files/ftp_upload/66005/66005fig4.jpg" data-altupdatedat="1747911167000" data-alt="Figure 4"> 
Figure 4: Design process of 3DHIP implant. (A) Segmentation of the region of interest from CT DICOM data. (B) Measurements of the native Norberg angles on the 3D model of the pelvis. (C) Rendering of a 3DHIP implant on the right hip, lateral view. (D) Rendering of bilateral 3DHIP implants, dorsal-ventral view. Abbreviation: 3DHIP = 3-dimensional-printed, hip implant. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="3D implant designs with highlighted features and an example model, illustrating mechanical support." class="xfigimg" src="/files/ftp_upload/66005/66005fig5.jpg" data-altupdatedat="1747911167000" data-alt="Figure 5"> 
Figure 5: Rendering of a designed 3DHIP implant. (A) Rendered image of the lateral/outer side of the 3DHIP implant. (B) Rendered image of the inner implant surface showing the porous surface allowing bone ingrowth for osseointegration. The bone attachment part (black arrowhead) of rendered implant incorporating 4 locking screw holes and the ventral ilium flange (black arrow) for assisting in correct implant positioning and stabilization. The rim extension part (red arrowhead) of the rendered implant with the internal 1.5 mm offset (red arrow) allowing unhindered joint capsule attachment. (C) Photograph of a titanium 3DHIP implant showcasing 4 screw holes arranged in the sequence for screw insertion. Abbreviation: 3DHIP = 3-dimensional-printed, hip implant. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Anatomy of canine hip, fascia latae dissection diagram, muscle structure analysis." class="xfigimg" src="/files/ftp_upload/66005/66005fig6.jpg" data-altupdatedat="1747911167000" data-alt="Figure 6"> 
Figure 6: Schematic illustration of skin incision. (A) Red oval marks the area in which the skin incision is made. (B) Magnification of red circle in (A). The skin incision is made using a #10-blade centered on the tip of the greater trochanter aiming at the cranial dorsal iliac spine. The incision length is approximately 8-15 cm. In the magnified image, the superficial leaf of fascia latae is incised along the cranial muscle border of the biceps femoris muscle. Orientation: left is cranial, top is dorsal. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig6large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Surgical procedure diagram; detailed anatomical dissection with labeled muscles and instruments." class="xfigimg" src="/files/ftp_upload/66005/66005fig7.jpg" data-altupdatedat="1747911167000" data-alt="Figure 7"> 
Figure 7: Schematic illustrations and photographs of an embalmed cadaver depicting the surgical approach for 3DHIP implantation. (A-D) Schematic illustrations and (E-H) photographs of an embalmed cadaver depict the surgical approach for 3DHIP implantation. (A and E) The red dotted line marks the line of the incision through the intermuscular septum between the superficial gluteal muscle, middle gluteal muscle, and the tensor fascia latae muscle. (B and F) Red dotted line marks the tenotomy site. The superficial and middle gluteal muscles are retracted dorsally to expose the deep gluteal muscle. Dissecting scissors are used to undermine the deep gluteal muscle near its insertion on the greater trochanter. A tenotomy is performed close (at 0.5-1 cm) to its insertion on the bone. (C and G) Adequate exposure for 3DHIP implant placement requires freeing the deep gluteal muscle from the joint capsule and lateral surface of the iliac body and partially freeing the iliacus muscle and rectus femoris muscles from the caudoventral border of the ilial shaft (red dotted line). (D and H) The 3DHIP implant is placed outside the capsule of the hip joint. For accuracy and ease of positioning, the ilium flange of the attachment part of the implant is placed under the ventral border of the exposed caudoventral iliac shaft. Orientation: left is cranial, top is dorsal. 1) biceps femoris muscle, 2) tensor fascia latae muscle, 3) fatty triangle, 4) superficial gluteal muscle, 5) middle gluteal muscle, 6) deep gluteal muscle/tendon, 7) vastus lateralis muscle, 8) hip joint capsule, 9) articularis coxae muscle, 10) caudal part of iliac body, 11) rectus femoris muscle, 12) ilium flange of the implant, and 13) rim extension part of the implant. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig7large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Canine hip fracture X-ray; surgical fixation device; orthopedic evaluation and healing assessment." class="xfigimg" src="/files/ftp_upload/66005/66005fig8.jpg" data-altupdatedat="1747911167000" data-alt="Figure 8"> 
Figure 8: Intraoperative fluoroscopy. After implant positioning and temporary fixation with one locking screw, intraoperative fluoroscopy is performed in (A) lateral and (B) latero-oblique views using a digital image intensifier to assess and compare the positioning of the implant to the preoperative planning. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig8large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Pelvic fixation techniques; X-ray, CT, and 3D models; orthopedic evaluation; bone stabilization." class="xfigimg" src="/files/ftp_upload/66005/66005fig9.jpg" data-altupdatedat="1747911167000" data-alt="Figure 9"> 
Figure 9: Examples of postoperative radiographs in three planes and postoperative CT scan after single-stage bilateral 3DHIP implant surgery in one dog. (A) Radiograph ventrodorsal view; (B) radiograph right latero-oblique view; (C) radiograph left latero-oblique view. 3D reconstruction from post-operative CT in lateral view showing the (D) right hip and (E) dorso-ventral view. (F) Postoperative CT of both hips in the transverse plane with a slice thickness of 5 mm. The 3DHIP implants were fixed with four locking screws on each side. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/66005fig9large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Outcome measurements</td>
			<td>Preoperatively</td>
			<td>Immediated postoperatively</td>
			<td>1.5 months</td>
			<td>3 months</td>
			<td>p-value</td>
		</tr>
		<tr>
			<td>NA (◦)</td>
			<td>87 ± 13a</td>
			<td>134 ± 19b</td>
			<td>-</td>
			<td>131 ± 20b</td>
			<td>&lt;0.001*</td>
		</tr>
		<tr>
			<td>LFO (%)</td>
			<td>22 ± 15a</td>
			<td>81 ± 16b</td>
			<td>-</td>
			<td>76 ± 19b</td>
			<td>&lt;0.001*</td>
		</tr>
		<tr>
			<td>PC (%)</td>
			<td>33 ± 17a</td>
			<td>79 ± 21b</td>
			<td>-</td>
			<td>77 ± 20b</td>
			<td>0.002*</td>
		</tr>
		<tr>
			<td>HCPI (%)</td>
			<td>31.44 ± 11.9a</td>
			<td>-</td>
			<td>20.39 ± 10.09b</td>
			<td>17.69 ± 10.8b</td>
			<td>&lt;0.001**</td>
		</tr>
	</tbody>
</table>
Table 1: Short-term results (Mean ± SD) of radiographic measurements using coronal CT and pain-related owner questionnaire using Helsinki Chronic Pain Index in dogs with hip dysplasia that underwent 3DHIP implantation. This table was modified from Kwananocha et al.18. HCPI (%) = 100% × total index score/maximum possible index score of the answered questions. a,bp-value &lt; 0.05 from Bonferroni, p-value* from repeated measure analysis, p-value** from generalized linear mixed model. Abbreviations: NA = Norberg angle; LFO = linear percentage of femoral head overlap; PC = percentage of femoral head coverage; SD = standard deviation; HCPI = Helsinki Chronic Pain Index.
Supplementary Video S1: Direct postoperative weight-bearing allowed with only short leash walks on a slip-resistant floor from the day after surgery. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/66005/Supplementary_video.zip" style="font-size: 14px;" target="_blank">Please click here to download this video.</a>

Read this Scientific Article Protocol about Author Spotlight: A Novel 3D-Printed Titanium Implant for Minimally Invasive Treatment of Hip Dysplasia in Young Dogs at JoVE.com

Author Spotlight: A Novel 3D-Printed Titanium Implant for Minimally Invasive Treatment of Hip Dysplasia in Young Dogs

This work describes a novel surgical technique for extracapsular implantation of a personalized, 3-dimensional-printed, joint-preserving implant. This novel treatment aims to restore hip stability in young adult dogs suffering from hip dysplasia with laxity by uniquely reproducing the anatomical shape of the acetabular rim of the hip joint.

Surgical Technique of the 3-Dimensional-printed Personalized Hip Implant for the Treatment of Canine Hip Dysplasia

Hip dysplasia causes major disability in dogs. Treatment options are limited to palliative treatment (e.g., pain relief, physical exercise, lifestyle ...

surgical-technique-3-dimensional-printed-personalized-hip-implant-for

Nanyang Technological University

Research

JoVE Journal

Biology

1.9K Views.  Utrecht University. De reikwijdte van ons onderzoek is de toepassing van een nieuwe chirurgische behandeling, 3D-heup, voor jonge honden met heupdysplasie die wordt gekenmerkt door heuplaxiteit. Het 3D-heupimplantaat is een patiëntspecifiek 3D-geprint titaniumimplantaat dat is ontworpen om de dorsale acetabulaire rand van het heupgewricht te verlengen en leidt tot gewrichtsstabiliteit en het verdwijnen van heuppijn. Heupdysplasie is een veel voorkomende orthopedische aandoening bij jonge honden die operatief ka...

Video: Auteur in de schijnwerpers: een nieuw 3D-geprint titaniumimplantaat voor minimaal invasieve behandeling van heupdysplasie bij jonge honden

A Rapid Technique for the Visualization of Live Immobilized Yeast Cells

We present here a simple, rapid, and extremely flexible technique for the immobilization and visualization of growing yeast cells by epifluorescence microscopy. The technique is equally suited for visualization of static yeast populations, or time courses experiments up to ten hours in length. My microscopy investigates epigenetic inheritance at the silent mating loci in S. cerevisiae. There are two silent mating loci, HML and HMR, which are normally not expressed as they are packaged in heterochromatin. In the sir1 mutant background silencing is weakened such that each locus can either be in the expressed or silenced epigenetic state, so in the population as a whole there is a mix of cells of different epigenetic states for both HML and HMR. My microscopy demonstrated that there is no relationship between the epigenetic state of HML and HMR in an individual cell. sir1 cells stochastically switch epigenetic states, establishing silencing at a previously expressed locus or expressing a previously silenced locus. My time course microscopy tracked individual sir1 cells and their offspring to score the frequency of each of the four possible epigenetic switches, and thus the stability of each of the epigenetic states in sir1 cells. See also  Xu et al., Mol. Cell 2006.

A rapid technique for the visualization of growing immobilized yeast cells, here applied to fluorescent reporters at the silent mating loci HML and HMR

We present here a simple, rapid, and extremely flexible technique for the immobilization and visualization of growing yeast cells by epifluorescence ...

Electroporation of Mycobacteria

High efficiency transformation is a major limitation in the study of mycobacteria. The genus Mycobacterium can be difficult to transform; this is mainly caused by the thick and waxy cell wall, but is compounded by the fact that most molecular techniques have been developed for distantly-related species such as Escherichia coli and Bacillus subtilis. In spite of these obstacles, mycobacterial plasmids have been identified and DNA transformation of many mycobacterial species have now been described. The most successful method for introducing DNA into mycobacteria is electroporation. Many parameters contribute to successful transformation; these include the species/strain, the nature of the transforming DNA, the selectable marker used, the growth medium, and the  conditions for the electroporation pulse. Optimized methods for the transformation of both slow- and fast-grower are detailed here. Transformation efficiencies for different mycobacterial species and with various selectable markers are reported.

Mycobacterial pathogenic strategies remain poorly understood. The slow growth rate of most species, the impenetrable nature of the cell-wall, and the hazards of working with pathogens make mycobacteria difficult to study and are largely responsible for our poor understanding of these organisms. In this video we will demonstrate the technique of electroporation, which involves subjecting cells to a brief high electrical impulse to allow the entry of DNA. It is the most widely used method for introducing DNA into mycobacterial cells.

High efficiency transformation is a major limitation in the study of mycobacteria. The genus Mycobacterium can be difficult to transform; this is mainly ...

Surgical Induction of Endolymphatic Hydrops by Obliteration of the Endolymphatic Duct

Surgical induction of endolymphatic hydrops (ELH) in the guinea pig by obliteration and obstruction of the endolymphatic duct is a well-accepted animal model of the condition and an important correlate for human Meniere's disease. In 1965, Robert Kimura and Harold Schuknecht first described an intradural approach for obstruction of the endolymphatic duct (Kimura 1965). Although effective, this technique, which requires penetration of the brain's protective covering, incurred an undesirable level of morbidity and mortality in the animal subjects. Consequently, Andrews and Bohmer developed an extradural approach, which predictably produces fewer of the complications associated with central nervous system (CNS) penetration.(Andrews and Bohmer 1989) 
The extradural approach described here first requires a midline incision in the region of the occiput to expose the underlying muscular layer. We operate only on the right side. After appropriate retraction of the overlying tissue, a horizontal incision is made into the musculature of the right occiput to expose the right temporo-occipital suture line. The bone immediately inferio-lateral the suture line (Fig 1) is then drilled with an otologic drill until the sigmoid sinus becomes visible. Medial retraction of the sigmoid sinus reveals the operculum of the endolymphatic duct, which houses the endolymphatic sac. Drilling medial to the operculum into the area of the endolymphatic sac reveals the endolymphatic duct, which is then packed with bone wax to produce obstruction and ultimately ELH. 
In the following weeks, the animal will demonstrate the progressive, fluctuating hearing loss and histologic evidence of ELH.

This video shows how to surgically obstruct the guinea pig's endolymphatic duct to produce endolymphatic hydrops.

Surgical induction of endolymphatic hydrops (ELH) in the guinea pig by obliteration and obstruction of the endolymphatic duct is a well-accepted animal ...

Individualized Stem-positioning in Calcar-guided Short-stem Total Hip Arthroplasty

Bone- and soft-tissue sparing short stems are increasingly used in total hip arthroplasty (THA). However, there are a large variety of models of short stems, differing in design and function. Calcar-guided short stems provide an anatomical curvature in the medial calcar region, thus, positioning is done individually alongside the calcar in the "round-the-corner" technique. Depending on the level of the neck's osteotomy, stems can be aligned individually in a large bandwidth of varus- and valgus anatomies. This differs from conventional total hip arthroplasty and potentially includes a severe learning curve. Given that a great variety of caput-collum-diaphyseal (CCD)-angles can be retained, the reconstruction of femoro-acetabular offsets can be achieved precisely. However, particularly extensive varus- and valgus positioning has raised concerns in regard to stability and bone remodeling. The purpose of the present manuscript is to showcase the implantation technique in calcar-guided short-stem THA and to summarize short-term clinical and radiological results.

This protocol describes the round-the-corner technique and the individualized stem-positioning of calcar-guided short stems alongside the medial calcar, depending on the level of the osteotomy. This differs from conventional total hip arthroplasty and includes a learning curve.

Bone- and soft-tissue sparing short stems are increasingly used in total hip arthroplasty (THA). However, there are a large variety of models of short ...

Medicine

Novel Percutaneous Approach for Deployment of 3D Printed Coronary Stenosis Implants in Swine Models of Ischemic Heart Disease

Minimally invasive methods for creating models of focal coronary narrowing in large animals are challenging. Rapid prototyping using three-dimensionally (3D) printed coronary implants can be employed to percutaneously create a focal coronary stenosis. However, reliable delivery of the implants can be difficult without the use of ancillary equipment. We describe the use of a mother-and-child coronary guide catheter for stabilization of the implant and for effective delivery of the 3D printed implant to any desired location along the length of the coronary vessel. The focal coronary narrowing was confirmed under coronary cineangiography and the functional significance of the coronary stenosis was assessed using gadolinium-enhanced first-pass cardiac perfusion MRI. We showed that reliable delivery of 3D printed coronary implants in swine models (n = 11) of ischemic heart disease can be achieved through repurposing mother-and-child coronary guide catheters. Our technique simplifies the percutaneous delivery of coronary implants to create closed-chest swine models of focal coronary artery stenosis and can be performed expeditiously, with a low procedural failure rate.

We describe a novel, cost-effective, and efficient technique for percutaneous delivery of three-dimensionally printed coronary implants to create closed-chest swine models of ischemic heart disease. The implants were fixed in place using a mother-and-child extension catheter with high success rate.

Minimally invasive methods for creating models of focal coronary narrowing in large animals are challenging. Rapid prototyping using three-dimensionally ...

3D Planning and Printing of Patient Specific Implants for Reconstruction of Bony Defects

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical field using the constantly developing 3D planning and printing capabilities. Computer-assisted design (CAD) and computer assisted manufacturing (CAM) are used to describe the 3D planning and manufacturing of the product. The planning and manufacturing of 3D surgical guides and reconstruction implants is performed almost exclusively by engineers. As technology advances and software interfaces become more user-friendly, it raises a question regarding the possibility of transferring the planning and manufacturing to the clinician. The reasons for such a shift are clear: the surgeon has the idea of what he wants to design, and he also knows what is feasible and could be used in the operating room. It allows him to be prepared for any scenario/unexpected results during the operation and allows the surgeon to be creative and express his new ideas using the CAD software. The purpose of this method is to provide clinicians with the ability to create their own surgical guides and reconstruction implants. In this manuscript, a detailed protocol will provide a simple method for segmentation using segmentation software and implant planning using a 3D design software. Following the segmentation and stl file production using segmentation software, the clinician could create a simple patient specific reconstruction plate or a more complex plate with a cradle for bone graft positioning. Surgical guides can be created for accurate resection, hole preparation for proper reconstruction plate positioning or for bone graft harvesting and re-contouring. A case of lower jaw reconstruction following plate fracture and nonunion healing of a trauma sustained injury is detailed.

This protocol describes the use of 3D planning and printing for reconstruction of bony defects. We use segmentation tools to create 3D models followed by 3D design software to create patient specific implants for reconstruction purposes concomitant to ablative surgery or as a second stage.

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical ...

Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve better results, even in the less experienced hand, or continue without it. As technology develops and becomes more user-friendly, we believe it is time to allow the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates allowing him full control over the process. We present here a protocol for 3D planning of the operation followed by 3D planning and printing of surgical guides and patient-specific fixation implants. During this process we use two commercial computer-assisted design (CAD) software. We also use a fused deposition&#160;modeling printer for the surgical guides and a selective laser sintering printer for the titanium patient-specific fixation implants. The process includes computed tomography (CT) imaging acquisition, 3D segmentation of the skull and facial bones from the CT, 3D planning of the operations, 3D planning of patient-specific fixation implant according to the final position of the bones, 3D planning of surgical guides for performing an accurate osteotomy and preparing the bone for the fixation plates, and 3D printing of the surgical guides and the patient-specific fixation plates. The advantages of the method include full control over the surgery, planned osteotomies and fixation plates, significant reduction in price, reduction in operation duration, superior performance and highly accurate results. Limitations include the need to master the CAD programs.

As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve ...

The Use of Mixed Reality in Custom-Made Revision Hip Arthroplasty: A First Case Report

The technology of 3D printing and visualization of anatomical structures is rapidly growing in various fields of medicine. A custom-made implant and mixed reality were used to perform complex revision hip arthroplasty in January 2019. The use of mixed reality allowed for a very good visualization of the structures and resulted in precise implant fixation. According to the authors' knowledge, this is the first described case report of the combined use of these two innovations. The diagnosis preceding the qualification for the procedure was the loosening of the left hip's acetabular component. Mixed reality headset and holograms prepared by engineers were used during the surgery. The operation was successful, and it was followed by early verticalization and patient rehabilitation. The team sees opportunities for technology development in joint arthroplasty, trauma, and orthopedic oncology.

A complex revision hip arthroplasty was performed using a custom-made implant and mixed reality technology. According to the authors&#39; knowledge, this is the first report of such procedure described in the literature.

The technology of 3D printing and visualization of anatomical structures is rapidly growing in various fields of medicine. A custom-made implant and mixed ...

Three-Dimensional Preoperative Virtual Planning in Derotational Proximal Femoral Osteotomy

Anterior knee pain (AKP) is a common pathology among adolescents and adults. Increased femoral anteversion (FAV) has many clinical manifestations, including AKP. There is growing evidence that increased FAV plays a major role in the genesis of AKP. Furthermore, this same evidence suggests that derotational femoral osteotomy is beneficial for these patients, as good clinical results have been reported. However, this type of surgery is not widely used among orthopedic surgeons.
The first step in attracting orthopedic surgeons to the field of rotational osteotomy is to give them a methodology that simplifies preoperative surgical planning and allows for the previsualization of the results of surgical interventions on computers. To that end, our working group uses 3D technology. The imaging dataset used for surgical planning is based on a CT scan of the patient. This 3D method is open access (OA), meaning it is accessible to any orthopedic surgeon at no economic cost. Furthermore, it not only allows for the quantification of femoral torsion but also for carrying out virtual surgical planning. Interestingly, this 3D technology shows that the magnitude of the intertrochanteric rotational femoral osteotomy does not present a 1:1 relationship with the correction of the deformity. Additionally, this technology allows for the adjustment of the osteotomy so that the relationship between the magnitude of the osteotomy and the correction of the deformity is 1:1. This paper outlines this 3D protocol.

This work presents a detailed surgical planning protocol using 3D technology with free open-source software. This protocol can be used to correctly quantify femoral anteversion and simulate derotational proximal femoral osteotomy for the treatment of anterior knee pain.

Anterior knee pain (AKP) is a common pathology among adolescents and adults. Increased femoral anteversion (FAV) has many clinical manifestations, ...

Clinical Application of Artificial Intelligence Preoperative Planning System Combined with Expert Database Retrieval in Complex Revision Hip Surgery

Accurate preoperative planning in revision hip arthroplasty is crucial for achieving successful outcomes. To enhance the intuitive evaluation of acetabular bone defect severity and leverage previous successful experience in revision hip arthroplasty, this study proposes a novel approach based on expert surgical case database retrieval and is initially implemented in clinical application.&#160;In this study, five patients who required revision hip arthroplasty were preoperatively planned to employ the expert case database surgical planning system.The patient&#39;s imaging data was entered into the system and matched with cases in the expert case database. Based on the expert&#39;s surgical experience, a revision surgery plan was recommended. If no suitable case was found, the model and position of the prosthesis were planned based on patient-specific reconstruction results. A total of five patients were enrolled in this study, four males and one female, with a mean age of 50.6 years. The diagnosis was aseptic prosthesis loosening after hip arthroplasty. The mean operative time was 123.2 min, and the mean intraoperative hemorrhage was 672 mL. No intraoperative complications, such as vascular or nerve injury, were observed. In Case 2, for instance, the application of this innovative planning scheme enabled the surgeon to delineate the revision surgery plan for this patient in the preoperative period, thereby reducing the operative time and intraoperative hemorrhage. Furthermore, patients could be apprised of the outcomes of analogous cases in advance. Leveraging a big data analysis approach through our comprehensive case database enables automated identification of matching expert treatment plans throughout the entire process. This particularly benefits inexperienced orthopedic surgeons by providing accurate guidance on surgical strategies to assist them in selecting appropriate prosthetic sizes and mounting positions. Additionally, the matching results can offer patients visualizations depicting predicted postoperative outcomes.

This study proposes a novel artificial intelligence preoperative planning approach based on expert surgical case database retrieval in revision hip arthroplasty. Additionally, the technique was initially employed in five patients, exhibiting a reduction in operative time and intraoperative hemorrhage.

Surgical Technique of the 3-Dimensional-printed Personalized Hip Implant for the Treatment of Canine Hip Dysplasia

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