A short tapered stem reduces intraoperative complications in primary total hip arthroplasty

Abstract

Background: While short-stem design is not a new concept, interest has surged with increasing utilization of less invasive techniques. Short stems are easier to insert through small incisions. Reliable long-term results including functional improvement, pain relief, and implant survival have been reported with standard tapered stems, but will a short taper perform as well?

Questions/purposes: We compared short, flat-wedge, tapered, broach-only femoral stems to standard-length, double-tapered, ream and broach femoral stems in terms of intraoperative complications, short-term survivorship, and pain and function scores.

Patients and methods: We retrospectively reviewed the records of 606 patients who had 658 THAs using a less invasive direct lateral approach from January 2006 to March 2008. Three hundred sixty patients (389 hips) had standard-length stems and 246 (269 hips) had short stems. Age averaged 63 years, and body mass index averaged 30.7 kg/m(2). We recorded complications and pain and function scores and computed short-term survival. Minimum followup was 0.8 months (mean, 29.2 months; range, 0.8-62.2 months).

Results: We observed a higher rate of intraoperative complications with the standard-length stems (3.1%; three trochanteric avulsions, nine femoral fractures) compared with the shorter stems (0.4%; one femoral fracture) and managed all complications with application of one or more cerclage cables. There were no differences in implant survival, Harris hip score, and Lower Extremity Activity Scale score between groups.

Conclusions: Fewer intraoperative complications occurred with the short stems, attesting to the easier insertion of these devices. While longer followup is required, our early results suggest shortened stems can be used with low complication rates and do not compromise the survival and functional outcome of cementless THA.

Level of evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Fig. 1

The MHP femoral component, introduced in 1984, is a double-tapered titanium stem with a proximal porous plasma-sprayed surface applied circumferentially around the stem. The middle section is grit-blasted and the distal section has a matte finish. The device is available in 14 standard offset sizes with a neck angle of 136.5°, diameters from 6 to 19 mm, and lengths from 135 to 180 mm, and 10 lateralized offset sizes with a neck angle of 131.5°, diameters from 8 to 17 mm, and lengths from 145 to 180 mm. (Reproduced with permission of Joint Implant Surgeons, Inc, New Albany, OH.)

Fig. 2

The TaperLoc^® Microplasty™ femoral component is a tapered, titanium, porous plasma-sprayed device available with either standard or lateralized offset and in 13 sizes, with diameters ranging from 5 to 25 mm and lengths ranging from 95 to 135 mm. The neck shaft angle is 138° for both standard and lateralized offset options, with lateralization achieved by shifting the trunnion medially. (Reproduced with permission of Joint Implant Surgeons, Inc, New Albany, OH.)

Fig. 3

The LIDL approach to the hip is performed by elevating the gluteus medius insertion along with the capsule in one continuous soft tissue sleeve from the anterior aspect of the trochanter. The origin of the vastus lateralis is left intact and dissection proceeds anterior and medial below the vastus muscle. (Reproduced with permission of Joint Implant Surgeons, Inc, New Albany, OH.)

Fig. 4A–E

(A) A preoperative radiograph of the left hip of a 79-year-old female patient who presented with severe pain and discomfort secondary to osteoarthritis shows severe joint space narrowing, sclerosis, and osteophyte and cyst formation. (B) An immediate postoperative radiograph shows treatment of cementless primary left THA with an 11- by 160-mm standard-length taper stem with lateralized offset and a 36-mm cobalt-chromium head with +6-mm neck articulated against highly crosslinked polyethylene. (C) At 2 weeks postoperative, the patient presented emergently with severe pain. A radiograph reveals a periprosthetic femoral fracture. (D) The patient’s femoral component was revised to a 14- by 175-mm standard-length tapered stem with lateralized offset, and the bone was secured with five cerclage cables. (E) A radiograph at 3 years after revision shows well-fixed components in satisfactory position and alignment. The patient had a HHS of 94 at latest followup.

Fig. 5A–C

(A) A preoperative radiograph of the left hip of a 64-year-old female patient who presented with severe pain and discomfort secondary to osteoarthritis shows severe joint space narrowing, sclerosis, and osteophyte and cyst formation. (B) A postoperative radiograph at 6 weeks shows treatment of cementless primary left THA with a 10- by 105-mm short taper stem and a 36-mm BIOLOX^® delta ceramic-on-highly-crosslinked polyethylene articulation (Ceramtec AG, Plochingen, Germany). (C) A radiograph at 4 years postoperatively shows well-fixed components in satisfactory position and alignment. The patient had a HHS of 96.5 at latest followup.