Bio-Derived Apatite As a Bone Graft for Vertebral Trauma.

INTRODUCTION: Traumatic spinal injury presents the potential for significant morbidity and mortality, and posterior fixation and fusion with bone grafts is a primary treatment for many vertebral fractures. While iliac crest autograft (ICBG) is considered the gold standard in bone grafting, this carries risks of morbidity at the donor site as well as prolonging surgery time. Bone graft substitutes (BGS) may provide a viable alternative to autograft but there is little published data concerning its use in trauma. Therefore, we conducted this retrospective review to evaluate the outcomes for fusion among patients who have received a BGS during posterolateral fusion (PLF) for vertebral trauma. MATERIALS AND METHODS: This was a retrospective, consecutive patient cohort. Over a six-month period, we identified 27 patients who had undergone PLF for spine trauma and in whom a BGS comprised of bovine-derived apatite was used. All patients had followed the standard of care. The postoperative plain film radiographs at three, six, 12, and (optionally) 24 months were independently assessed by an orthopedic surgeon who was not affiliated with the hospital. RESULTS: We documented a radiographically observed fusion rate of 85% and a successful treatment rate of 92%. There were no adverse events related to the BGS. Patients who received a BGS with ICBG spent significantly longer in surgery than other patients. There were no adverse events related to the BGS. CONCLUSIONS: The spondylodesis rate following surgery in which the BGS was used in PLF, whether alone, mixed with local bone, or mixed with ICBG is comparable to the rates that have been reported for iliac crest autograft in these indications. The data indicates that the BGS provides a useful adjunct in PLF for the treatment of traumatic spine vertebral injuries. The use of BGS also allows for shorter time in surgery, which may reduce resource utilization and thus lower the total costs of the procedure. CLINICAL RELEVANCE: Posterolateral fusion can be obtained with the use of a bio-derived BGS while reducing the time in surgery by avoiding the second procedure necessary to harvest ICBG. This may be advantageous in cases where the surgeon wishes to minimize operating time or when the availability of autograft is limited.

An excellent 5-year survival rate despite a high incidence of distal femoral cortical hypertrophy in a short hip stem.

BACKGROUND: Although reported results on short stems sound very promising, the occurrence of distal femoral cortical hypertrophy is often observed. The aim of the present study was to report 5-year survival data of a commercially available trochanter sparing short stem and investigate the clinical impact of distal femoral cortical hypertrophy on the outcome. METHODS: 123 total hip arthroplasties were performed on 120 patients from April 2008 to May 2010 (mean age 62, range 29-89 years; 71 hips from male patients, 58%). Clinical and radiological data were collected preoperative, at 6 weeks, 1, 2, 3, and 5 years postoperative to assess the outcome. Radiographs taken immediately postoperative as well as 1 and 5 years postoperative were used to identify and assess cortical hypertrophy. RESULTS: 1 stem had to be revised due to aseptic loosening, resulting in a Kaplan-Meier survival analysis with endpoint for stem revision of 99.2% (95% Confidence Interval 94.1-99.9) at 5 years. 96 radiological and 95 clinical follow-ups were analysed 5 years postoperative. 68 (71%) hips showed distal femoral cortical hypertrophy after 5 years. The average Harris Hip Score and Oxford Hip Score improved 33 (standard deviation (SD) 15.1, range 2-70), 18 (SD 12.1, range -10-43) points, respectively. Overall 16% of the patients reported thigh pain, unrelated to the presence of cortical hypertrophy. DISCUSSION: This short stem shows an excellent 5-year survival rate and good clinical outcome despite a high incidence of cortical hypertrophy. However, the question of the mechanism of load transfer arises.

The Thrust Plate Hip Prosthesis: A Follow-Up of 15-20 Years With 102 Implants.

BACKGROUND: Between November 1992 and January 1999, a cohort of 102 thrust plate hip prostheses was implanted. METHODS: We now clinically and radiologically evaluate the remaining 73 prostheses with a mean follow-up of 17.2 years. RESULTS: The Harris Hip Score increased from 51.4 points preoperatively to 94.3 points at the time of this follow-up. No further changes in the radiologic findings occurred since the first follow-up, published in 2005, conducted 2-8 years after implantation. Within 15 to 20 years after primary implantation of the 102 prostheses, 6 aseptic loosenings occurred, which correspond to a cumulated survival rate of 94.7% at 17 and 91.8% at 18 years. CONCLUSION: Although the thrust plate hip prostheses is no longer marketed, the biomechanical behaviour of this unique, clinically successful prosthesis deserves attention.

Prospective clinical and radiostereometric analysis of the Fitmore short-stem total hip arthroplasty.

INTRODUCTION: Uncemented short, curved femoral stems may help save proximal bone stock during total hip arthroplasty (THA) and facilitate insertion in minimal invasive surgery. The aim of this 2 year, prospective, single-center study was to examine the stability and migration of the Fitmore (®) stem in THA using model-based radiostereometric analysis (RSA), and thus predict the implant's long-term survival. In addition, we evaluated the stem's clinical performance using standard clinical measures. PATIENTS AND METHODS: We conducted a prospective cohort study of 34 THA patients who received the short Fitmore Hip Stem (Zimmer, Winterthur, Switzerland). At 3, 6, 12 and 24 months postoperatively, the patients underwent clinical evaluation and radiostereometric analysis (RSA) to measure stem migration. RESULTS: RSA analysis revealed a mean subsidence of -0.39 mm (95 % CI -0.60 to -0.18) at 3 months with no further migration after 2 years. Mean internal rotation along the longitudinal axis was 1.09° (95 % CI 0.52-1.66) at 2 years, versus 0.85° (95 % CI 0.44-1.26) at 3 months. The Harris hip score improved from 60 (range 30-80) preoperatively to 99 (range 83-100) after 2 years. Three patients underwent revision due to deep infection, non-specific thigh pain and aseptic loosening in one case. CONCLUSION: We conclude that the Fitmore Hip Stem stabilizes after 3 months and achieves good short-term clinical results in most cases.

Trochleaplasty for patellar instability due to trochlear dysplasia: A minimum 2-year clinical and radiological follow-up of 19 knees.

BACKGROUND: Recurrent patellar dislocation may be associated with trochlear dysplasia. Trochleaplasty is a surgical procedure which strives to deepen the trochlear groove. We evaluated the clinical and radiological effect of trochleaplasty after a minimum follow-up of 2 years. PATIENTS AND METHODS: We examined 19 knees in 16 patients at a mean of 3 years after trochleaplasty. Postoperatively, a subjective questionnaire, a Kujala score, and tests for potential patellar redislocation and apprehension were evaluated. On radiographs we evaluated the preoperative and postoperative crossing sign, trochlear depth, trochlear bump, and patellar height. On CT scans, the pre- and postoperative tibial tuberosity to trochlear groove distance (TTTG) and the patellar inclination angle were measured. RESULTS: 16 of 19 knees improved subjectively. The Kujala score increased from 56 to 80 points at the latest follow-up. None of the patients sustained a redislocation. 5 patients had medial parapatellar tenderness, including 4 with persistent apprehension. Radiological signs of trochlear dysplasia were corrected. INTERPRETATION: Patellofemoral instability with underlying trochlear dysplasia can be treated successfully by trochleaplasty.

Radiological findings and clinical results of 102 thrust-plate femoral hip prostheses: a follow-up of 2 to 8 years.

We report the radiological and clinical outcome of 102 consecutive femoral hip arthroplasty we prospectively followed up in 84 patients using the third generation of the thrust-plate prosthesis with a mean period of follow-up of 58 (range, 26-100) months. Four implants were revised: 2 because of an infection and 2 because of aseptic loosening. The thrust-plate prosthesis, which allows preservation of part of the femoral neck, was used in younger patients, 80% were younger than 60 years. In 95 implants, contact was maintained between thrust plate and underlying bone, and in only 3 instances, without any clinical manifestation, did the bone retract from the thrust plate to the extent that a gap appeared. The extent of radiologically evident bone contact with the flat surface of the thrust plate, as a consequence of the bone remodeling behavior, is described and retrospectively classified. The average Harris hip score increased from 51 points preoperatively to 96 points postoperatively at the last follow-up. Survivorship analysis according to Kaplan-Meier showed a survival rate of 98% after 6 years, with no further losses up to the end of the 8-year follow-up period.