Heterotopic ossification after 2-incision total hip arthroplasty.

We examined the incidence of heterotopic ossification (HO) in a consecutive series of total hip arthroplasties (THAs) performed with the so-called minimally invasive, 2-incision technique. Standard preoperative hip radiographs were used to grade the extent of degenerative arthritis, and comparable follow-up radiographs at 30 months after surgery were used to detect and classify HO formation. Of 121 patients, 32 (26.5%) developed HO, with the Brooker class distribution as follows: stage I, 16 patients; stage II, 9 patients; stage III, 6 patients; stage IV, 1 patient. In this study, HO formation after 2-incision THA occurred with nearly the same frequency as that reported in other studies after standard THA.

Primary TKA with a zirconia ceramic femoral component.

This article presents the 2-year clinical results of primary total knee arthroplasty (TKA) performed with a zirconia ceramic femoral component. A posterior-stabilized TKA was performed for degenerative arthritis in 36 patients (39 knees). The components included a zirconia femoral component, a cobalt-chrome alloy tibial baseplate, and a polyethylene patella; all were implanted with bone cement. The ultra-high molecular-weight polyethylene-bearing insert had a deep-dish, ultra-congruent design. At the 2-year interval, mean Western Ontario and McMaster Universities (WOMAC) osteoarthritis indices improved from 41 to 86, and mean Knee Society Scores improved from 40 to 92. Revision to constrained implants was necessary in one patient for persistent knee instability after trauma. These early results are encouraging, but more data are needed to determine whether ceramics are a suitable alternative to metal countersurfaces in TKAs.

A method for removing the polyethylene liner during revision total hip arthroplasty.

Extraction of the polyethylene liner is necessary if acetabular fixation screws and the metal acetabular shell are to be revised during total hip arthroplasty. In some situations, revision of the polyethylene liner alone may be indicated for excessive wear and osteolysis. A simple method for dissociating the liner from the shell is described in this report. No special instruments are needed with this technique.

Early complications of primary total hip replacement performed with a two-incision minimally invasive technique.

BACKGROUND: Total hip replacement performed through a small incision theoretically results in less trauma to the underlying structures, reduced blood loss, less pain, and a shorter hospital stay, but it may result in increased complications, particularly early in a surgeon's experience with a new technique. In the present study, we reviewed the early results of two techniques involving the use of smaller incisions; specifically, we evaluated one series of primary total hip replacements that had been performed through two small incisions and another series of total hip replacements that had been performed through a single small incision. METHODS: Eighty-nine consecutive primary total hip replacements were performed with use of the two-incision technique as described by Mears and Berger; all procedures were performed without cement and with use of fluoroscopic guidance. Outcomes data were reviewed at a minimum of six months following the procedure. The results of these procedures were retrospectively compared with those of a historical control series of ninety-six total hip replacements that had been performed by the same surgeon with use of a single mini-incision technique. No special attempt was made to discharge any patient early from the hospital. In preparation for the use of the two-incision technique, the surgeon attended a two-day seminar that included cadaveric training and mentoring by surgeons who had experience with this technique. RESULTS: In the two-incision group, nine patients (nine hips; 10%) required repeat surgery because of a femoral fracture that had been identified postoperatively (two hips), dislocation (one hip), a wound complication (two hips), or subsidence and loosening of the femoral implant (four hips). Twenty-two patients (twenty-two hips; 25%) sustained an injury of the lateral femoral cutaneous nerve, and one patient (one hip) had a neuropraxia of the femoral nerve. In the comparative series of ninety-six total hip arthroplasties that had been performed with use of a single mini-incision and a direct lateral exposure of the hip joint, the overall complication rate was 6% (six of ninety-six) and the reoperation rate was 3% (three of ninety-six). The rate of complications associated with the two-incision technique decreased significantly as the surgeon gained experience with the procedure (p = 0.0202). CONCLUSIONS: Although total hip arthroplasty with use of the two-incision technique was performed by a surgeon who was experienced in the performance of total hip replacement surgery with use of a single small incision, the rates of complications and repeat surgery associated with the two-incision technique initially were very high. While the rate diminished with increasing experience, total hip replacement with use of two incisions and fluoroscopic guidance is a technically demanding procedure that may be associated, especially initially, with higher rates of complications and repeat surgery.

Case report: superficial femoral artery injury resulting from cerclage wiring during revision THA.

Vascular injuries around the hip are uncommon with hip arthroplasty. However, given the close proximity of the external iliac and femoral vessels to the hip, iatrogenic injury may occur. We describe a case of superficial femoral artery injury occurring during revision THA using an extended trochanteric osteotomy, bulk allograft, and cerclage wires. We review the available literature on vascular injury in hip arthroplasty and illustrate the great care necessary when placing cerclage wires and the importance of prompt recognition of these potentially devastating complications.

Early failure of unicompartmental knee arthroplasty leading to revision.

The most common previously reported modes of failure of unicompartmental knee arthroplasty (UKA) in the first and second decades are polyethylene wear, progression of arthritis, and component loosening. The purpose of this study is to describe an early mechanism of failure of the medial UKA. Thirty-two consecutive revisions from UKA to total knee arthroplasty were retrospectively reviewed. The predominant mode of failure observed in 15 (47%) of 32 knees was medial tibial collapse. Of these, 87% were an all-polyethylene design, and 7 of 15 failed in less than 16 months and required more complex reconstruction with stems, augments, and screws and cement. Increased tibial slope was associated with posterior tibial collapse. In our series, knees that failed by medial tibial collapse had more significant bone defects and required more complex reconstructions than is currently reported in the literature.

The significance of metal staining on alumina femoral heads in total hip arthroplasty.

Metallic transfer to alumina can occur intraoperatively and while reducing a dislocated total hip, when the femoral head contacts the rim of the metal acetabular shell. To see if metal discoloration is associated with changes to the alumina, we examined 14 metal-stained alumina femoral heads retrieved from ceramic-on-ceramic articulations using electron microscopy and noncontact profilometry. Metal staining was associated with surface damage to alumina on the femoral heads removed from unstable total hips. The surface roughness of metal-stained alumina heads was significantly greater than that of unused alumina heads. Alumina femoral heads should be protected against contact with the metal cup during total hip implantation. Dislocations in ceramic-on-ceramic total hips should be addressed early because of possible damage to the surface.

Anterior trochanteric slide osteotomy for primary total hip arthroplasty. Review of nonunion and complications.

The radiographic results of 73 anterior trochanteric slide osteotomies were retrospectively reviewed at an average of 36 months after primary hip arthroplasty to determine the incidence of nonunion of the trochanter and complications related to trochanteric hardware. In each case, the trochanter was retracted anteriorly, with the gluteus medius and vastus lateralis muscle insertions left intact. Reattachment was performed with 2 monofilament wires or cables passed through the lesser trochanter in each case. Ninety-two percent of the trochanters healed; nonunion was associated with anterior displacement of the trochanteric fragment with external rotation of the femur. The incidence of repeat surgery for hardware-related problems was 28%. Although the slide osteotomy prevented proximal migration of the trochanteric fragment, the incidence of hardware complications was too high to justify the routine use of this approach in primary hip arthroplasty.

Early complications of primary total hip replacement performed with a two-incision minimally invasive technique. Surgical technique.

BACKGROUND: Total hip replacement performed through a small incision theoretically results in less trauma to the underlying structures, reduced blood loss, less pain, and a shorter hospital stay, but it may result in increased complications, particularly early in a surgeon's experience with a new technique. In the present study, we reviewed the early results of two techniques involving the use of smaller incisions; specifically, we evaluated one series of primary total hip replacements that had been performed through two small incisions and another series of total hip replacements that had been performed through a single small incision. METHODS: Eighty-nine consecutive primary total hip replacements were performed with use of the two-incision technique as described by Mears and Berger; all procedures were performed without cement and with use of fluoroscopic guidance. Outcomes data were reviewed at a minimum of six months following the procedure. The results of these procedures were retrospectively compared with those of a historical control series of ninety-six total hip replacements that had been performed by the same surgeon with use of a single miniincision technique. No special attempt was made to discharge any patient early from the hospital. In preparation for the use of the two-incision technique, the surgeon attended a two-day seminar that included cadaveric training and mentoring by surgeons who had experience with this technique. RESULTS: In the two-incision group, nine patients (nine hips; 10%) required repeat surgery because of a femoral fracture that had been identified postoperatively (two hips), dislocation (one hip), a wound complication (two hips), or subsidence and loosening of the femoral implant (four hips). Twenty-two patients (twenty-two hips; 25%) sustained an injury of the lateral femoral cutaneous nerve, and one patient (one hip) had a neuropraxia of the femoral nerve. In the comparative series of ninety-six total hip arthroplasties that had been performed with use of a single mini-incision and a direct lateral exposure of the hip joint, the overall complication rate was 6% (six of ninety-six) and the reoperation rate was 3% (three of ninety-six). The rate of complications associated with the two-incision technique decreased significantly as the surgeon gained experience with the procedure (p = 0.0202). CONCLUSIONS: Although total hip arthroplasty with use of the two-incision technique was performed by a surgeon who was experienced in the performance of total hip replacement surgery with use of a single small incision, the rates of complications and repeat surgery associated with the two-incision technique initially were very high. While the rate diminished with increasing experience, total hip replacement with use of two incisions and fluoroscopic guidance is a technically demanding procedure that may be associated, especially initially, with higher rates of complications and repeat surgery.